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Patent Searching and Data


Title:
STACKING TRAY STRUCTURE FOR EASY ACCESS
Document Type and Number:
WIPO Patent Application WO/2021/118636
Kind Code:
A1
Abstract:
A stacking tray apparatus including a lift member, a tray, and a movement restricting member. The lift member is liftable to a top position and a bottom position. The tray is supported by the lift member, the tray being movable to a loading position to load a recording medium and to an extraction position, the extraction position being in a recording medium discharge direction from the loading position. The movement restricting member to prevent the tray being moved in the recording medium discharge direction when the lift member is located at the top position and to allow the tray to be moved to the extraction position when the lift member is located at the bottom position.

Inventors:
FUKASAWA EIJI (KR)
LEE YOUGBOK (KR)
Application Number:
PCT/US2020/037151
Publication Date:
June 17, 2021
Filing Date:
June 11, 2020
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
HEWLETT PACKARD DEVELOPMENT CO (US)
International Classes:
B41J13/10; B65H31/10
Foreign References:
US7850170B22010-12-14
GB666515A1952-02-13
GB2383030A2003-06-18
DE102005031574A12007-01-11
Attorney, Agent or Firm:
KO, Steve Sokbong et al. (US)
Download PDF:
Claims:
WHAT IS CLAIMED IS: 1. A stacking tray apparatus comprising: a lift member liftable to a top position and a bottom position; a tray supported by the lift member, the tray to be movable to a loading position at the top position to load a recording medium, to be movable from the loading position to an extraction position at the bottom position, and to be movable in a recording medium discharge direction; and a movement restricting member to restrict the tray being moved in the recording medium discharge direction when the lift member is located at the top position and to allow the tray to be moved to the extraction position when the lift member is located at the bottom position. 2. The stacking tray apparatus of claim 1, further comprising a rear end supporting member to support a rear end of recording medium loaded into the tray, wherein, when the lift member is located at the bottom position for the tray to be located at the extraction position, the tray is detachably attached to the rear end supporting member so that the tray and the rear end supporting member are movable together from the loading position to the extraction position. 3. The stacking tray apparatus of claim 2, further comprising a deviation preventing member positionable to a first position to allow the tray to be detachably attached to the rear end supporting member when the rear end supporting member is located at the loading position at the bottom position and positionable to a second position to attach the tray to the rear end supporting member so the tray does not deviate from the rear end supporting member when the rear end supporting member is deviated from the loading position at the bottom position. 4. The stacking tray apparatus of claim 3, further comprising a first elastic member to apply an elastic force to the deviation preventing member to position the deviation preventing member at the second position, wherein the deviation preventing member is to move from the second position to the first position as the tray is moved from the extraction position to the loading position. 5. The stacking tray apparatus of claim 2, further comprising a locking lever having a locking position to lock the tray to the lift member at the loading position and having a release position to allow the tray to move to the extraction position. 6. The stacking tray apparatus of claim 2, further comprising a position detecting sensor to detect whether the tray is returned to the loading position. 7. The stacking tray apparatus of claim 2, further comprising a first motor to drive the lift member and the rear end supporting member. 8. The stacking tray apparatus of claim 7, further comprising: a first shaft and a second shaft separated in a lift direction of the lift member; a belt supported by the first shaft and the second shaft; a first locking portion provided at the belt; a second locking portion provided at the lift member and coupled to the first locking portion; a rack gear provided at the rear end supporting member; a pinion connected to the second shaft and to be moved by the lift member to a position engaged with the rack gear when the lift member is located at the bottom position; and a second elastic member to apply an elastic force to the pinion to separate the pinion from the rack gear.

9. The stacking tray apparatus of claim 8, wherein the first locking portion includes an upper locking protrusion and a lower locking protrusion separated in the lift direction, and the second locking portion includes an upper locking groove into which the upper locking protrusion is insertable and which is open downward and a lower locking jaw located under the lower locking protrusion. 10. The stacking tray apparatus of claim 2, further comprising: a first motor to lift the lift member; and a second motor to move the rear end supporting member to the loading position and the extraction position. 11. A stacking tray apparatus comprising: a lift member liftable to a top position and a bottom position; and a tray to receive recording medium and which is pivotable from a first inclination position inclined upward at a first angle from a rear end portion toward a front end portion in a recording medium discharge direction to a second inclination position inclined at a second angle smaller than the first angle from the rear end portion toward the front end portion when the lift member is located at the bottom position. 12. The stacking tray apparatus of claim 11, further comprising: a pivot member supporting the tray and supported by the lift member to be pivoted to the first inclination position and the second inclination position; a pivot restricting protrusion; and a pivot restricting slot into which the pivot restricting protrusion is insertable to selectively allow t the pivot member to pivot according to the position of the lift member, wherein the pivot restricting slot includes: a pivot restricting section to maintain the pivot member at the first inclination position; and an opening portion provided at a lower end portion of the pivot restricting section, wherein the pivot restricting protrusion is to deviate from the pivot restricting section to allow the pivot member to pivot from the first inclination position to the second inclination position as the lift member approaches the bottom position. 13. The stacking tray apparatus of claim 12, further comprising: a pinion gear portion provided at the pivot member; and a rack gear to engage with the pinion gear portion to pivot the pivot member as the lift member approaches the bottom position. 14. The stacking tray apparatus of claim 11, wherein the tray is supported by the lift member, and the lift member is to pivot from the first inclination position to the second inclination position at the bottom position. 15. The stacking tray apparatus of claim 14, further comprising: a belt to drive a first locking portion in a lift section to lift the lift member to the top position and the bottom position and to drive the first locking portion in a pivot section to pivot the lift member located at the bottom position to the first inclination position and the second inclination position; a second locking portion having a slot shape cut in a lift direction of the lift member, the first locking portion being insertable into the slope shape; an upper guide roller and a lower guide roller to be separated in the lift direction; and an integrated guide slot including a lift guide portion corresponding to the lift section and a pivot guide portion corresponding to the pivot section, the upper guide roller and the lower guide roller being insertable into the integrated guide slot, wherein a side wall of the pivot guide portion in a discharge direction of the recording medium is inclined in the discharge direction to pivot the lift member to the first inclination position and the second inclination position when the lift member is located at the bottom position.

Description:
STACKING TRAY STRUCTURE FOR EASY ACCESS BACKGROUND [0001] An image forming apparatus prints an image on paper, for example, a recording medium. The paper completely printed and then discharged from the image forming apparatus is discharged into a discharge space. The discharge space may be provided with a tray for loading the discharged paper. The tray may be lifted (ascended or descended) according to the amount of loaded paper. [0002] A finisher may be used for the image forming apparatus. The finisher may be located between the image forming apparatus and the discharge space. The finisher performs a finishing process such as end binding, saddle stitching, or folding on the paper discharged from the image forming apparatus. The finishing processed paper may be discharged into the discharge space and loaded into the tray. [0003] A user may check the paper loaded into the discharge space and extract the paper from the discharge space. In the case of a discharge space with its top and bottom portions closed, it may be difficult to check the paper inside the discharge space. Also, when the height of the discharge space is small, it may not be easy to extract the paper by putting a hand into the discharge space. BRIEF DESCRIPTION OF DRAWINGS [0004] FIG. 1 is a schematic configuration diagram of an example of an image forming apparatus. [0005] FIG. 2 is a schematic configuration diagram of an example of an image forming apparatus. [0006] FIG. 3 is a schematic side configuration diagram of an example of a stacking tray apparatus. [0007] FIG.4A is a schematic plan configuration diagram of an example of the stacking tray apparatus illustrated in FIG.3, which illustrates a state where a tray is located at a loading position. [0008] FIG. 4B is a cross-sectional view of the stacking tray apparatus taken along line X1-X1' of FIG.4A. [0009] FIG. 5 is a schematic plan configuration diagram of an example of the stacking tray apparatus illustrated in FIG.3, which illustrates a state where a tray is located at an extraction position. [0010] FIG. 6 is a schematic plan view of an example of a stacking tray apparatus. [0011] FIG. 7 is a perspective view illustrating an example of a rear end supporting member. [0012] FIG. 8 is a diagram illustrating a state where a tray and a rear end supporting member are coupled to each other. [0013] FIG. 9 is a diagram illustrating a state where a tray and a rear end supporting member are moved together to an extraction position. [0014] FIG. 10 is a perspective view illustrating an example of a rear end supporting member. [0015] FIG. 11 is a diagram illustrating a state where a tray and a rear end supporting member are coupled to each other. [0016] FIG. 12 is a diagram illustrating a state where a tray and a rear end supporting member are moved together to an extraction position. [0017] FIG. 13 is a schematic side view of an example of a stacking tray apparatus. [0018] FIG.14 is a schematic perspective view of an example of a structure for driving a rear end supporting member by using a first driving motor. [0019] FIG. 15 illustrates a state where a pinion is located at a separation position in the structure illustrated in FIG.14. [0020] FIG. 16 illustrates a state where a pinion is located at an engagement position in the structure illustrated in FIG.14. [0021] FIG. 17 illustrates a state where a lift member is located at a bottom position in an example of the stacking tray apparatus illustrated in FIG.3. [0022] FIGS.18 and 19 are schematic diagrams of an example of a connection structure between a lift member and a belt applied to an example of the stacking tray apparatus illustrated in FIG.3. [0023] FIG. 20 is a schematic side view of an example of a stacking tray apparatus. [0024] FIG.21 is a schematic configuration diagram of an example of an image forming apparatus. [0025] FIG. 22 is a schematic side view of an example of a stacking tray apparatus. [0026] FIG.23 is a side view illustrating a state where a lift member approaches a bottom position in an example of the stacking tray apparatus illustrated in FIG. 22. [0027] FIG. 24 is a side view illustrating a state where a lift member reaches a bottom position in an example of the stacking tray apparatus illustrated in FIG. 22. [0028] FIG. 25 is a diagram illustrating in detail a guide rail and a pivot restricting slot illustrated in FIG.22. [0029] FIG. 26 is a schematic side view of an example of a stacking tray apparatus. [0030] FIG.27 is a side view illustrating a state where a lift member approaches a bottom position in an example of the stacking tray apparatus illustrated in FIG. 26. [0031] FIG. 28 is a side view illustrating a state where a lift member reaches a bottom position in an example of the stacking tray apparatus illustrated in FIG. 26. [0032] FIG.29 is a perspective view illustrating in detail a lift member illustrated in FIG.26. DETAILED DESCRIPTION [0033] Hereinafter, examples of a stacking tray apparatus for loading the paper discharged from an image forming apparatus or a finisher will be described with reference to the drawings. In the drawings, like reference numerals may denote like elements, and the size or thickness of each element may be exaggerated for clarity of description. [0034] FIG.1 is a schematic configuration diagram of an example of an image forming apparatus. Referring to FIG.1, the image forming apparatus may include a printing unit 1 printing an image on a recording medium. An example of the recording medium is paper P. The term paper will be used throughout, but the recording medium is not limited to paper itself and may be other types of recording medium as well. The printing unit 1 may print an image on a recording medium by various printing methods such as an electrophotographic method, an inkjet method, a thermal transfer method, or a thermal sublimation method. The printed paper P may be discharged into a discharge space 2 through a discharge port 1-1. A tray 3 may be installed in the discharge space 2. The paper P discharged from the printing unit 1 into the discharge space 2 may be loaded into the tray 3. [0035] FIG.2 is a schematic configuration diagram of an example of an image forming apparatus. Referring to FIG.2, the image forming apparatus may include a printing unit 1 printing an image on paper P, for example, a recording medium, and a finisher 4 performing a finishing process on the paper P discharged from the printing unit 1. For example, the finisher 4 may perform a finishing process such as end binding, saddle stitching, or folding on the paper P. The finishing processed paper P may be discharged into a discharge space 2 through a discharge port 4-1 and loaded into a tray 3. [0036] In the examples of the image forming apparatus illustrated in FIGS. 1 and 2, in order to prevent the paper P from falling from the tray 3, the tray 3 may be installed to be inclined upward from a rear end portion toward a front end portion thereof with respect to a discharge direction TB of the paper P. The tray 3 may be vertically lifted (raised or lowered) inside the discharge space 2 as indicated by an arrow TA (lift direction). The image forming apparatus may be configured to lift the tray 3 in a lift direction TA according to the amount of paper P discharged into the discharge space 2. The lift direction TA may be a loading direction of paper P and may be substantially perpendicular to the discharge direction TB. [0037] In the examples of the image forming apparatus described above, the discharge space 2 may have a shape in which top and bottom portions are closed and a side portion is partially open. A user may check and extract the paper P in the discharge space 2 through the open side portion. When a height H of the discharge space 2 is not sufficient, it may not be easy for the user to check the paper P inside the discharge space 2 and extract the paper P from the discharge space 2. There may be a need for a stacking tray apparatus capable of easily checking and extracting the paper P of the discharge space 2. [0038] As one way, the tray 3 may be moved to an extraction position (dotted lines in FIGS. 1 and 2) moved in the discharge direction TB from a loading position (solid lines in FIGS. 1 and 2). In this case, the tray 3 and the paper P loaded thereon may be partially exposed outside the discharge space 2 and the user may easily access the paper P. [0039] The loading position may be a position where the tray 3 approaches the discharge port 1-1 or 4-1, and the extraction position may be a position where the tray 3 is separated from the discharge port 1-1 or 4-1 in the discharge direction TB. The tray 3 may be moved from the loading position to the extraction position by being moved in the discharge direction TB of the paper P. Hereinafter, an example of the stacking tray apparatus for moving the tray 3 from the loading position to the extraction position will be described. [0040] FIG. 3 is a schematic side configuration diagram of an example of a stacking tray apparatus. FIG.4A is a schematic plan configuration diagram of an example of the stacking tray apparatus illustrated in FIG. 3, which illustrates a state where a tray 3 is located at a loading position. FIG.4B is a cross-sectional view of the stacking tray apparatus taken along line X1-X1' of FIG.4A. FIG.5 is a schematic plan configuration diagram of an example of the stacking tray apparatus illustrated in FIG.3, which illustrates a state where a tray 3 is located at an extraction position. [0041] Referring to FIGS. 3, 4A, and 4B, the stacking tray apparatus may include a lift member 100 supported to be lifted to a top position (solid lines in FIG. 3) and a bottom position (dashed lines in FIG. 3), a tray 3 mounted on the lift member 100 and movable to a loading position for loading paper P and to an extraction position moved from the loading position in a paper discharge direction TB, and a movement restricting member 170 allowing the tray 3 to be moved from the loading position to the extraction position when the lift member 100 is located at the bottom position. [0042] The lift member 100 may be liftably installed on a frame 8. The frame 8 may be, for example, a frame constituting the stacking tray apparatus or may be a wall provided with the discharge port 1-1 of the printing unit 1or the discharge port 4-1 of the finisher 4. The lift member 100 may be lifted to the top position and the bottom position in a state that the tray 3 is located at the loading position. As an example, the lift member 100 may be lifted by being guided by a guide rail 121 extending in the lift direction TA in a lift guide member 120 provided at the frame 8. The lift member 100 may be provided with a guide roller 101 inserted into the guide rail 121. In the present example, a pair of guide rollers 101 separated in the lift direction TA may be used such that the lift member 100 may be lifted in the lift direction TA without being inclined. [0043] The stacking tray apparatus may include a lift driving unit for electrically lifting the lift member 100. As an example, the lift driving unit may include a first shaft 151 and a second shaft 152 arranged to be separated in the lift direction TA, a belt 153 driven by being supported by the first shaft 151 and the second shaft 152, a first locking portion 155 provided at the belt 153, and a second locking portion 123 provided at the lift member 100 and coupled to the first locking portion 155. The lift driving unit may include a first driving motor M1. The first driving motor M1 may rotate any one of the first shaft 151 and the second shaft 152. The first shaft 151 may be adjacent to the top position, and the second shaft 152 may be adjacent to the bottom position. As an example, the belt 153 may be a timing belt. In this case, a pulley 154 provided at the first shaft 151 and the second shaft 152 to support the belt 153 may be a timing pulley. Also, the belt 153 and pulley 154 may respectively be a flat belt and a flat pulley. The first locking portion 155 may have a protrusion shape. The second locking portion 123 may have a groove shape in which a lower side is open such that the first locking portion 155 may be inserted thereinto. According to this configuration, the first locking portion 155 may be inserted into the second locking portion 123 such that the lift member 100 may be maintained at a certain position between the top position and the bottom position. When the first driving motor M1 is rotated in a forward direction and thus the first locking portion 155 is lowered, the lift member 100 may be lowered toward the bottom position by gravity. When the first driving motor M1 is rotated in a reverse direction, the first locking portion 155 may be raised to push the second locking portion 123 and thus the lift member 100 may be raised toward the top position. [0044] The tray 3 may be supported by the lift member 100 to be moved to the loading position and the extraction position. For example, a slide member 130 may be coupled to the lift member 100, and the tray 3 may be supported by the slide member 130. The slide member 130 may be supported by the lift member 100 to be moved in the discharge direction TB. The slide member 130 of the present example may have a two-stage rail structure. The slide member 130 may include a first slide member 131 supported by the lift member 100 to be slid in the discharge direction TB and a second slide member 132 supported by the first slide member 131 to be slid in the discharge direction TB. The lift member 100 may be provided with a first guide rail 122 extending in the discharge direction TB, and the first slide member 131 may be provided with a first guide roller 134 supported by the first guide rail 122. The first slide member 131 may be provided with a second guide rail 133 extending in the discharge direction TB, and the second slide member 132 may be provided with a second guide roller 135 supported by the second guide rail 133. The tray 3 may be supported by the second slide member 132. [0045] The movement restricting member 170 may allow the tray 3 to be moved from the loading position to the extraction position when the lift member 100 is located at the bottom position and may not allow the tray 3 to be moved to the extraction position when the lift member 100 is located at a position other than the bottom position. That is, the movement restricting member 170 may maintain the tray 3 at the loading position when the lift member 100 is located at a position other than the bottom position. [0046] As an example, the movement restricting member 170 may include a movement restricting slot 171 extending in the lift direction TA, a movement restricting protrusion 172 provided at the slide member 130, for example, the second slide member 132, to be inserted into the movement restricting slot 171, and an opening portion 173 provided at the movement restricting slot 171 such that the movement restricting protrusion 172 may be deviated from the movement restricting slot 171 in the discharge direction TB when the lift member 100 is located at the bottom position. The movement restricting slot 171 may be installed at the frame 8. The movement restricting protrusion 172 may have, for example, a roller form. In the present example, the movement restricting protrusion 172 may be provided at any one of the tray 3 and the slide member 130. In the present example, the movement restricting protrusion 172 may be provided at the second slide member 132. [0047] A lift operation of the tray 3 and a manual movement operation of the tray 3 from the loading position to the extraction position will be described with reference to FIGS.3 to 5. [0048] First, as illustrated by solid lines in FIG. 3, the lift member 100 may be located at the top position or at a certain position between the top position and the bottom position. In this case, because the movement restricting protrusion 172 is inserted into the movement restricting slot 171, the tray 3 may be located at the loading position. In this state, paper P may be loaded into the tray 3. Depending on the amount of paper P loaded into the tray 3, the lift driving unit may lift the lift member 100 to a suitable position between the top position and the bottom position. In order to extract the paper P loaded into the tray 3, the lift member 100 may be moved to the bottom position. When the lift member 100 reaches the bottom position as illustrated by dashed lines in FIG. 3, the movement restricting protrusion 172 may be aligned with the opening portion 173 in the discharge direction TB and thus the movement restricting protrusion 172 may be deviated from the movement restricting slot 171 through the opening portion 173. Thus, the tray 3 may be moved from the loading position to the extraction position. [0049] When the tray 3 is pulled in the discharge direction TB, the first slide member 131 and the second slide member 132 may be sequentially slid in the discharge direction TB. The first slide member 131 may be slid in the discharge direction TB with respect to the lift member 100 until the first guide roller 134 contacts an end portion 122-1 of the first guide rail 122 on the side of the discharge direction TB. The second slide member 132 may be slid in the discharge direction TB with respect to the first slide member 131 until the end portion thereof on the side of the discharge direction TB contacts a stopper 133-1 provided at the first slide member 131. Accordingly, the tray 3 may be located at the extraction position and the user may easily check and extract the paper P on the tray 3. [0050] When the tray 3 is pushed in the opposite direction of the discharge direction TB in the state illustrated in FIG. 5, the first slide member 131 and the second slide member 132 may be sequentially slid in the opposite direction of the discharge direction TB. The first slide member 131 may be slid in the opposite direction of the discharge direction TB with respect to the lift member 100 until an end portion 133-2 in the opposite direction of the discharge direction TB contacts a stopper 122-2 provided at the lift member 100. The second slide member 132 may be slid in the opposite direction of the discharge direction TB with respect to the first slide member 131 until the second guide roller 135 contacts the end portion 133-2 of the second guide rail 133 in the opposite direction of the discharge direction TB. Accordingly, the tray 3 may be located at the loading position and the movement restricting protrusion 172 may be inserted into the movement restricting slot 171 through the opening portion 173. The lift driving unit may lift the lift member 100 toward the top position. The tray 3 may be maintained at the loading position by the movement restricting member 170. [0051] When the lift member 100 is deviated from the bottom position in a state where the tray 3 is located at the extraction position, the movement restricting protrusion 172 and the opening portion 173 may be misaligned and thus the tray 3 may not be returned to the loading position. Thus, in the state where the tray 3 is located at the extraction position, the lift member 100 may need to be maintained at the bottom position. That is, the lift of the lift member 100 may not be allowed when the tray 3 is deviated from the loading position, and the lift of the lift member 100 may be allowed when the tray 3 is located at the loading position. [0052] FIG. 6 is a schematic plan view of an example of a stacking tray apparatus. Referring to FIG. 6, the stacking tray apparatus may include a position detecting sensor 124 detecting whether the tray 3 is returned to the loading position. A detection piece 32 may be provided at the tray 3. The position detecting sensor 124 may detect the detection piece 32 of the tray 3. The position detecting sensor 124 may detect the position of the tray 3 by detecting the detection piece 32. The position detecting sensor 124 may be, for example, a photo sensor including a light emitting portion and a light receiving portion. When the detection piece 32 is located between the light emitting portion and the light receiving portion, no light may be detected by the light receiving portion, and when the detection piece 32 is deviated from between the light emitting portion and the light receiving portion, light may be detected by the light receiving portion. For example, when the tray 3 is located at the loading position as illustrated in FIG.6, the detection piece 32 may be detected by the position detecting sensor 124, and when the tray 3 is moved in the discharge direction TB and deviated from the loading position, the detection piece 32 may not be detected by the position detecting sensor 124. Thus, when the detection piece 32 is detected by the position detecting sensor 124, it may be determined that the tray 3 is located at the loading position, and when the tray 3 is located at the loading position, the lift driving unit may be controlled to lift the lift member 100. [0053] The stacking tray apparatus may include a locking lever 6 having a locking position (solid lines in FIG.6) for locking the tray 3 to the lift member 100 at the loading position and a release position (dashed lines in FIG.6) for allowing the movement of the tray 3 to the extraction position. The locking lever 6 may be installed, for example, at the tray 3 to be pivoted to the locking position and the release position. A locking spring 61 may apply an elastic force to the locking lever 6 in a direction to locate the locking lever 6 at the locking position. A portion 62 of the locking lever 6 may be exposed outside from the tray 3 such that the user may operate the locking lever 6. When the tray 3 is located at the loading position, the locking lever 6 may be switched to the locking position by the elastic force of the locking spring 61 and thus a hook 63 of the locking lever 6 may be locked into a locking groove 125 provided at the lift member 100. The tray 3 may be locked at the loading position. Because the detection piece 32 is detected by the position detecting sensor 124, it may be determined that the tray 3 is located at the loading position. As illustrated by dashed lines of FIG.6, the locking lever 6 may be pivoted to be switched to the release position. Then, the hook 63 of the locking lever 6 may be deviated from the locking groove 125 provided at the lift member 100 and the tray 3 may be moved to the extraction position. When the tray 3 is deviated from the loading position, because the detection piece 32 is not detected by the position detecting sensor 124, it may be determined that the tray 3 is not located at the loading position. [0054] Referring to FIGS. 1 and 2, the stacking tray apparatus may include a rear end supporting member 5 supporting the rear end of the paper P loaded into the tray 3. The tray 3 may be inclined upward from the rear end portion toward the front end portion in the discharge direction TB, and the rear end of the paper P loaded into the tray 3 may be contactually supported by the rear end supporting member 5. In order to prevent the paper P loaded into the tray 3 from slipping in the opposite direction of the discharge direction TB and then falling from the tray 3 when the tray 3 is moved to the extraction position, the rear end supporting member 5 may be moved in the discharge direction TB together with the tray 3. When the lift member 100 is located at the bottom position, the tray 3 located at the loading position may be coupled to the rear end supporting member 5. Thus, the tray 3 and the rear end supporting member 5 may be moved together from the loading position to the extraction position. [0055] FIG. 7 is a perspective view illustrating an example of a rear end supporting member 5. FIG.8 is a diagram illustrating a state where a tray 3 and a rear end supporting member 5 are coupled to each other. FIG. 9 is a diagram illustrating a state where a tray 3 and a rear end supporting member 5 are moved together to an extraction position. In FIGS.8 and 9, a structure for lifting the tray 3 is omitted. [0056] Referring to FIGS. 7 to 9, the rear end supporting member 5 may be supported by the frame 8 to be moved in the discharge direction TB. The rear end supporting member 5 may include a rear end supporting portion 51 supporting the rear end of the paper P. The rear end supporting portion 51 may have a shape extending in the lift direction TA. A plurality of rear end supporting portions 51 may be provided in the widthwise direction of the paper P. [0057] The rear end supporting member 5 may be slidable in the discharge direction TB. For example, the rear end supporting member 5 may be supported by the frame 8 to be slid in the discharge direction TB. The frame 8 may be, for example, a frame constituting the stacking tray apparatus or may be a wall provided with the discharge port 1-1 or 4-1 of the postprocessing unit 4 or the printing unit 1. As an example, the rear end supporting member 5 may include a sliding guide 54 extending in the opposite direction of the discharge direction TB with respect to the rear end supporting portion 51. The sliding guide 54 may be supported to be slid by, for example, a plurality of rollers 55. Accordingly, the rear end supporting member 5 may be slid in the discharge direction TB and the opposite direction thereof. [0058] The rear end supporting member 5 may be coupled to the tray 3 to be moved to the loading position and the extraction position together with the tray 3. When the lift member 100 is located at the bottom position, the tray 3 located at the loading position may be coupled to the rear end supporting member 5. The tray 3 may be provided with a coupling protrusion 31. The coupling protrusion 31 may have a rib shape extending in the lift direction TA. The rear end supporting member 5 may be provided with a coupling groove 53 into which the coupling protrusion 31 is inserted. For example, a groove forming portion 52 may be located to face the rear end supporting portion 51 in the discharge direction TB to form the coupling groove 53 into which the coupling protrusion 31 of the tray 3 is inserted between the rear end supporting portion 51 and the groove forming portion 52. [0059] According to this configuration, when the lift member 100 is moved to the bottom position, the coupling protrusion 31 of the tray 3 located at the loading position may be inserted into the coupling groove 53 of the rear end supporting member 5 as illustrated in FIG.8. Accordingly, as illustrated in FIG.9, the tray 3 and the rear end supporting member 5 may be moved together to the extraction position. [0060] In the state where the tray 3 is located at the extraction position, the lift member 100 may need to be maintained at the bottom position. That is, the lift of the lift member 100 may not be allowed when the tray 3 is deviated from the loading position, and the lift of the lift member 100 may be allowed when the tray 3 is located at the loading position. In the present example, because the tray 3 and the rear end supporting member 5 are moved together to the extraction position, the position of the rear end supporting member 5 may be detected to detect whether the tray 3 is returned to the loading position. The rear end supporting member 5 may be provided with a detection piece 56. A position detecting sensor 57 may detect the position of the rear end supporting member 5 by detecting the detection piece 56. The position detecting sensor 57 may be, for example, a photo sensor including a light emitting portion and a light receiving portion. When the detection piece 56 is located between the light emitting portion and the light receiving portion, no light may be detected by the light receiving portion, and when the detection piece 56 is deviated from between the light emitting portion and the light receiving portion, light may be detected by the light receiving portion. For example, when the tray 3 is located at the loading position as illustrated in FIG. 8, the detection piece 56 may be detected by the position detecting sensor 57, and when the tray 3 is moved in the discharge direction TB and deviated from the loading position as illustrated in FIG.9, the detection piece 56 may not be detected by the position detecting sensor 57. Thus, when the detection piece 56 is detected by the position detecting sensor 57, it may be determined that the tray 3 is located at the loading position, and when the tray 3 is located at the loading position, the lift driving unit may be controlled to lift the lift member 100. [0061] FIG. 10 is a perspective view illustrating an example of a rear end supporting member 5. FIG.11 is a diagram illustrating a state where a tray 3 and a rear end supporting member 5 are coupled to each other. FIG.12 is a diagram illustrating a state where a tray 3 and a rear end supporting member 5 are moved together to an extraction position. In FIGS. 11 and 12, a structure for lifting the tray 3 is omitted. The present example may be different from the example illustrated in FIGS. 7 to 10 in that it has a structure for selectively allowing the attachment/detachment between the tray 3 and the rear end supporting member 5. Hereinafter, the difference from the example illustrated in FIGS.7 to 10 will be mainly described. [0062] Referring to FIGS. 10 to 12, a deviation preventing member 58 is illustrated. The deviation preventing member 58 may be located at a first position (FIG. 11) for allowing the tray 3 to be detachably attached to the rear end supporting member 5 when the rear end supporting member 5 is located at the loading position. The deviation preventing member 58 may be located at a second position (FIG. 12) for coupling the tray 3 to the rear end supporting member 5 such that the tray 3 may not be deviated from the rear end supporting member 5 when the rear end supporting member 5 is deviated from the loading position. [0063] For example, the deviation preventing member 58 may be installed at the rear end supporting member 5 to be moved to the first position and the second position. The deviation preventing member 58 may be provided with a locking protrusion 58-1. As illustrated in FIG. 12, when the deviation preventing member 58 is located at the second position, the locking protrusion 58-1 may be inserted into a locking groove 33 provided at the coupling protrusion 31 such that the tray 3 may not be moved in the lift direction TA. As illustrated in FIG. 11, when the deviation preventing member 58 is located at the first position, the locking protrusion 58-1 may be deviated from the locking groove 33 of the tray 3. [0064] The deviation preventing member 58 may be moved to the first position and the second position in conjunction with the movement of the tray 3 and the rear end supporting member 5. A first elastic member 59 may apply an elastic force to the deviation preventing member 58 in a direction to locate the deviation preventing member 58 at the second position. As the tray 3 and the rear end supporting member 5 are moved from the loading position to the extraction position, the deviation preventing member 58 may be moved from the first position to the second position by the elastic force of the first elastic member 59. As the tray 3 and the rear end supporting member 5 are moved from the extraction position to the loading position, the deviation preventing member 58 may be moved from the second position to the first position. [0065] As an example, the deviation preventing member 58 may be provided with an interference portion 58-2 interfering with the frame 8. When the tray 3 and the rear end supporting member 5 are located at the loading position, the interference portion 58-2 may interfere with the frame 8. The deviation preventing member 58 may be pushed in the opposite direction of the elastic force of the first elastic member 59 to be located at the first position as illustrated in FIG. 11. In this state, the tray 3 may be detachably attached to the rear end supporting member 5 and may be lifted. As the tray 3 and the rear end supporting member 5 are moved in the discharge direction TB in a state where the tray 3 is coupled to the rear end supporting member 3, the deviation preventing member 58 may be moved from the first position to the second position by the elastic force of the first elastic member 59. Thus, when the tray 3 and the rear end supporting member 5 are deviated from the loading position, the tray 3 may not be deviated from the rear end supporting member 5. As the tray 3 and the rear end supporting member 5 again approach from the extraction position to the loading position, the interference portion 58-2 may interfere with the frame 8 and the deviation preventing member 58 may be moved from the second position to the first position. When the tray 3 and the rear end supporting member 5 reach the loading position, the deviation preventing member 58 may be returned to the first position. [0066] FIG. 13 is a schematic side view of an example of a stacking tray apparatus. In FIG.13, a structure for lifting the tray 3 is omitted. Referring to FIG. 13, the tray 3 may be provided with a paper sensor 7 for detecting whether the paper P is loaded thereinto. The paper sensor 7 may include, for example, a pivoting arm 71 pivoted according to whether the paper P is loaded, and a sensor unit 72 for detecting the pivoting arm 71. The sensor unit 72 may be, for example, a photo sensor. The sensor unit 72 may be connected to the image forming apparatus by a signal line 73. As the tray 3 is lifted in the lift direction TA or moved in the discharge direction TB, the signal line 73 may be exposed and stretched outside the stacking tray apparatus. In view of this point, the stacking tray apparatus may include a tension applying unit for applying tension to the signal line 73. The tension applying unit may include, for example, a movable member 74, which is movable in the discharge direction TB and to which the signal line 73 is connected, and a spring 75, which applies an elastic force to the movable member 74 in the opposite direction of the discharge direction TB. For example, the movable member 74 may be supported by a rail 76 extending in the discharge direction TB. According to this configuration, even when the tray 3 is moved in the lift direction TA and the discharge direction TB, the signal line 73 may be maintained in a tensioned state without being stretched outside the stacking tray apparatus. [0067] The tray 3 and the rear end supporting member 5 may be electrically moved to the extraction position and the loading position. Hereinafter, examples of a structure for electrically moving the tray 3 and the rear end supporting member 5 to the extraction position and the loading position will be described. [0068] The tray 3 and the rear end supporting member 5 may be driven independently of the lift member 100. For example, the stacking tray apparatus may include a first driving motor M1 (see FIG. 3) for lifting the lift member 100 and may further include a second driving motor M2 for moving the rear end supporting member 5 to the loading position and the extraction position as illustrated in FIGS. 7 and 8. As illustrated in FIGS. 7 and 8, the stacking tray apparatus may include a rack gear 54-1 provided at the sliding guide 54 and a pinion 54-2 engaged with the rack gear 54-1. By driving the second driving motor M2 to rotate the pinion 54-2, the rear end supporting member 5 and the tray 3 may be moved to the loading position and the extraction position. [0069] The tray 3 and the rear end supporting member 5 may be driven by the first driving motor M1 for lifting the lift member 100. FIG. 14 is a schematic perspective view of an example of a structure for driving a rear end supporting member 5 by using a first driving motor M1. FIG. 15 illustrates a state where a pinion 54-2 is located at a separation position in the structure illustrated in FIG. 14. FIG.16 illustrates a state where the pinion 54-2 is located at an engagement position in the structure illustrated in FIG. 14. In FIGS. 14 to 16, a structure for lifting the lift member 100 is omitted. [0070] Referring to FIGS. 3 and 14 to 16, illustrated are the first shaft 151 and the second shaft 152 separated in the lift direction TA of the lift member 100, the belt 153 driven by being supported by the first shaft 151 and the second shaft 152, the first locking portion 155 provided at the belt 153, the second locking portion 123 provided at the lift member 100 and coupled to the first locking portion 155, the rack gear 54-1 provided at the rear end supporting member 5, the pinion 54-2 rotated by being connected to the second shaft 152 and moved by the lift member 100 to a position engaged with the rack gear 54-1 when the lift member 100 is located at the bottom position, and a second elastic member 54-3 applying an elastic force to the pinion 54-2 in a direction to separate the pinion 54-2 from the rack gear 54-1. [0071] The structure of the rear end supporting member 5 may be substantially the same as that described in FIGS. 7 to 9 except that the rack gear 54-1 is provided at the upper surface of the sliding guide 54, the guide roller 55 supports both side portions of the sliding guide 54, and the position of the position detecting sensor 57 and the detection piece 56 is different therefrom. [0072] The pinion 54-2 may be rotated by being connected to the second shaft 152 close to the bottom position among the first shaft 151 and the second shaft 152. As an example, the pinion 54-2 may be installed at a bracket 161 to be pivoted to the engagement position and the separation position. The bracket 161 may be pivoted on a connection shaft 162 to the separation position and the engagement position. The connection shaft 162 may be rotated by being connected to the second shaft 152. For example, the connection shaft 162 and the second shaft 152 may be connected to each other by a connection belt 163. A gear 164 may be installed at the connection shaft 162. The gear 164 may be engaged with the pinion 54-2. [0073] The pinion 54-2 may be elastically biased by the second elastic member 54-3 in a direction to be located at a separation position separated from the rack gear 54-1 and may be moved by the lift member 100 to an engagement position engaged with the rack gear 54-1 when the lift member 100 is moved to the bottom position. As an example, the lift member 100 may be provided with a first contact portion 102. As the lift member 100 is moved to the bottom position, the first contact portion 102 may contact a second contact portion 165 provided at the bracket 161 and may push and pivot the bracket 161 to the engagement position. [0074] FIG.17 illustrates a state where a lift member 100 is located at a bottom position in an example of the stacking tray apparatus illustrated in FIG. 3. With reference to FIGS.3 and 14 to 17, a process of electrically moving the rear end supporting member 5 and the tray 3 from the loading position to the extraction position will be described. [0075] When the first driving motor M1 is driven in the forward direction in the state illustrated in FIG.3, the first locking portion 155 may be moved downward and the lift member 100 may also be moved downward in a state where the second locking portion 123 and the first locking portion 155 are coupled to each other. The pinion 54-2 may be located at the separation position as illustrated in FIG.15. [0076] As the lift member 100 approaches the bottom position, the first contact portion 102 may contact the second contact portion 165 of the bracket 161 to pivot the second contact portion 165 in the opposite direction of the elastic force of the second elastic member 54-3. When the lift member 100 reaches the bottom position as illustrated in FIG. 17, the pinion 54-2 may reach the engagement position engaged with the rack gear 54-1 as illustrated in FIG. 16. The movement restricting protrusion 172 may be aligned with the opening portion 173 provided at the movement restricting slot 171. The coupling protrusion 31 of the tray 3 may be inserted into the coupling groove 53 of the rear end supporting member 5 such that the tray 3 and the rear end supporting member 5 may be moved together to the extraction position. Because the guide roller 101 is caught by the lower end portion of the guide rail 121, the lift member 100 may no longer be lowered and may be maintained at the bottom position. [0077] The first driving motor M1 may be continuously driven in the forward direction to move the tray 3 and the rear end supporting member 5 to the extraction position. The forward driving force of the first driving motor M1 may be transmitted to the pinion 54-2 through the connection belt 163, the connection shaft 162, and the gear 164. When the pinion 54-2 is rotated in the forward direction, the rear end supporting member 5 and the tray 3 may be moved from the loading position to the extraction position. The second locking portion 123 may have a groove shape in which a lower side is open. Thus, when the first driving motor M1 is continuously driven in the forward direction in a state where the lift member 100 is located at the bottom position, the belt 153 may be continuously driven in the forward direction because the first locking portion 155 is deviated from the second locking portion 123 as illustrated by the dashed lines in FIG. 17. When the tray 3 and the rear end supporting member 5 reach the extraction position, the first driving motor M1 may be stopped. [0078] The first driving motor M1 may be driven in the reverse direction to move the tray 3 and the rear end supporting member 5 from the extraction position to the loading position. The reverse driving force of the first driving motor M1 may be transmitted to the pinion 54-2 through the connection belt 163, the connection shaft 162, and the gear 164. When the pinion 54-2 is rotated in the reverse direction, the rear end supporting member 5 and the tray 3 may be moved from the extraction position to the loading position. The detection piece 56 may be detected by the position detecting sensor 57 and thus it may be determined that the rear end supporting member 5 and the tray 3 have reached the loading position. [0079] After the rear end supporting member 5 and the tray 3 reach the loading position, when the first driving motor M1 is continuously driven in the reverse direction, the first locking portion 155 may be inserted into the second locking portion 123 through the open lower portion of the second locking portion 123 to push the second locking portion 123 upward. Then, the lift member 100 may be raised from the bottom position to the top position, and the coupling protrusion 31 of the tray 3 may be deviated from the coupling groove 53 of the rear end supporting member 5. As the lift member 100 is raised, the first contact portion 102 may be separated from the second contact portion 165 and the bracket 161 may be pivoted by the elastic force of the second elastic member 54-3 from the engagement position to the separation position. Thus, the pinion 54-2 may be separated from the rack gear 54-1. When the tray 3 reaches the top position or a suitable position between the top position and the bottom position, the first driving motor M1 may be stopped. [0080] Although not illustrated in the drawings, a torque limiter may be located between the gear 164 and the connection shaft 162. When a foreign material is caught between the rear end supporting member 5 and the frame 8 when the rear end supporting member 5 is moved from the extraction position to the loading position, a slip may occur between the gear 164 and the connection shaft 162 due to the torque limiter. Accordingly, damage due to overload of the first driving motor M1 may be prevented. [0081] FIGS.18 and 19 are schematic diagrams of an example of a connection structure between a lift member 100 and a belt 153 applied to an example of the stacking tray apparatus illustrated in FIG.3. Referring to FIG.18, the first locking portion 155 may include an upper locking protrusion 155-1 and a lower locking protrusion 155-2 separated in the lift direction TA. The second locking portion 123 may include an upper locking groove 123-1 into which the upper locking protrusion 155-1 inserted and which is open downward and a lower locking jaw 123-2 which is located under the lower locking protrusion 155-2 such that the upper locking protrusion 155-1 may not be deviated from the upper locking groove 123-1. [0082] The upper locking groove 123-1 may have a groove shape in which a lower side is open. Thus, in the case where the lower locking protrusion 155-2 and the lower locking protrusion 123-2 are omitted, when the tray 3 is raised, the lift member 100 may also be raised and thus the upper locking protrusion 155-1 may be deviated from the upper locking groove 123-1. According to the present example, because the lower locking jaw 123-2 is located under the lower locking protrusion 155-2, even when the tray 3 is raised, the lower locking jaw 123-2 may be caught on the lower locking protrusion 155-2 located thereon and thus the upper locking protrusion 155-1 may not be deviated from the upper locking groove 123-1. [0083] As illustrated in FIG. 19, when the lift member 100 reaches the bottom position, the lower locking jaw 123-2 may be located under the second shaft 152. The shortest distance between the lower locking jaw 123-2 and the second shaft 152 may be greater than the distance between the second shaft 152 and the upper locking protrusion 155-1 and the distance between the second shaft 152 and the lower locking protrusion 155-2. Thus, when the first driving motor M1 is continuously driven in the forward direction after the lift member 100 reaches the bottom position, the lower locking protrusion 155-2 may be deviated from the lower locking jaw 123-2 by rotating around the second shaft 152 without interfering with the lower locking jaw 123-2. Also, the upper locking protrusion 155-1 may be deviated from the lower locking jaw 123-2 by rotating around the second shaft 152 after being deviated from the upper locking groove 123-1. Thus, the example of the connection structure between the lift member 100 and the belt 153 illustrated in FIG.18 may be applied to the structure of FIGS.14 to 15 in which the first driving motor M1 is used to move the rear end supporting member 5 and the tray 3 to the loading position and the extraction position. [0084] A structure for moving the lift member 100 to the top position and the bottom position may be variously modified. FIG. 20 is a schematic side view of an example of a stacking tray apparatus. The example illustrated in FIG.20 may be different from the example illustrated in FIG. 3 in that a rack-pinion combination is used instead of a belt driving structure to move the lift member 100 to the top position and the bottom position. Referring to FIG. 20, the lift member 100 may be located at the bottom position. The lift member 100 may be provided with a rack gear portion 103 extending in the lift direction TA. A pinion 104 may be engaged with the rack gear portion 103. The pinion 104 may be driven by the first driving motor M1. Through this configuration, by driving the first driving motor M1 in the forward/reverse directions, the lift member 100 may be moved to the top position and the bottom position. The examples illustrated in FIGS. 6 to 13 may be applied to the example of the stacking tray apparatus illustrated in FIG.20. [0085] The examples applying the structure for moving the tray 3 to the extraction position (dotted lines in FIGS. 1 and 2) moved in the discharge direction TB from the loading position (solid lines in FIGS. 1 and 2) have been described above as the stacking tray apparatus capable of easily checking and extracting the paper P of the discharge space 2. [0086] Hereinafter, other examples of the stacking tray apparatus capable of easily checking and extracting the paper P of the discharge space 2 will be described. [0087] FIG.21 is a schematic configuration diagram of an example of an image forming apparatus. Referring to FIG. 21, the image forming apparatus may include a printing unit 1 printing an image on paper P, for example, a recording medium. The printing unit 1 may print an image on the paper P by various printing methods such as an electrophotographic method, an inkjet method, a thermal transfer method, or a thermal sublimation method. The printed paper P may be discharged into the discharge space 2. As illustrated by dotted lines in FIG.21, the image forming apparatus may further include a finisher 4 performing a finishing process on the paper P discharged from the printing unit 1. For example, the finisher 4 may perform a finishing process such as end binding, saddle stitching, or folding on the paper P. The finishing processed paper P may be discharged into the discharge space 2. [0088] A tray 3 into which the discharged paper P is loaded may be installed in the discharge space 2. In order to prevent the paper P from falling from the tray 3, the tray 3 may be installed to be inclined upward from the rear end portion toward the front end portion thereof with respect to the discharge direction TB of the paper P. The tray 3 may be lifted in the lift direction TA in the discharge space 2. The image forming apparatus may be configured to lift the tray 3 in a lift direction TA according to the amount of paper P discharged into the discharge space 2. [0089] In order to prevent the paper P from falling from the tray 3, the tray 3 may be installed to be inclined upward at a first angle from the rear end portion toward the front end portion thereof with respect to the discharge direction TB of the paper P. When the tray 3 reaches the bottom position, the tray 3 may be pivoted from a first inclination position 3a inclined upward at a first angle from the rear end portion toward the front end portion in the paper discharge direction TB to a second inclination position 3b inclined at a second angle smaller than the first angle from the rear end portion toward the front end portion thereof. The first angle and the second angle may be inclination angles with respect to the horizontal direction. As an example, the second angle may be "0" degree. In other words, the tray 3 may be horizontal at the second inclination position 3b. According to this structure, the upper space of the tray 3 in the discharge space 2 may become larger and thus the paper P loaded into the tray 3 may be easily accessed. Hereinafter, an example of the stacking tray apparatus using a structure for adjusting the inclination angle of the tray 3 will be described. [0090] FIG. 22 is a schematic side view of an example of a stacking tray apparatus. FIG. 23 is a side view illustrating a state where a lift member 200 approaches a bottom position in an example of the stacking tray apparatus illustrated in FIG. 22. FIG. 24 is a side view illustrating a state where a lift member 200 reaches a bottom position in an example of the stacking tray apparatus illustrated in FIG.22. FIG.25 is a diagram illustrating in detail a guide rail 210 and a pivot restricting slot 310. [0091] Referring to FIGS. 22 to 25, a lift member 200 supported to be lifted to the top position and the bottom position and a pivot member 300 supported by the lift member 200 to be pivoted to the first inclination position and the second inclination position are illustrated. The tray 3 may be supported by the pivot member 300. [0092] The lift member 200 may be guided by a guide rail 210 to be lifted to the top position and the bottom position. Referring to FIGS.22 and 25, the guide rail 210 may extend in the lift direction TA. The lift member 200 may be provided with guide rollers 201 and 202 inserted into the guide rail 210. Two guide rollers 201 and 202 may be separated in the lift direction TA in order to allow the lift member 200 to be stably lifted in the lift direction TA. A pinion-rack gear structure or the belt driving structure described above may be used as a structure of the lift driving unit for lifting the lift member 200. In the present example, the pinion-rack gear structure may be used. The lift member 200 may be provided with a rack gear portion 203 extending in the lift direction TA. A pinion 220 may be engaged with the rack gear portion 203. The first driving motor M1 may drive the pinion 220. Through this configuration, by driving the first driving motor M1 in the forward/reverse directions, the lift member 200 may be lifted in the lift direction TA. [0093] The pivot member 300 may be supported by the lift member 200 to be pivoted to the first inclination position and the second inclination position. As an example, the pivot member 300 may be supported to be pivoted to the first inclination position and the second inclination position around a rotation shaft 202-1 of the guide roller 202 located below among the guide rollers 201 and 202. [0094] The pivot member 300 may be guided by a pivot restricting slot 310 to be pivoted to the first inclination position and the second inclination position. Referring to FIGS.22 and 25, the pivot restricting slot 310 may extend in the lift direction TA. The pivot member 300 may be provided with a pivot restricting protrusion 301 inserted into the pivot restricting slot 310. The pivot restricting protrusion 301 may have a rotated roller form. The pivot restricting protrusion 301 may be located above the guide roller 202. The pivot restricting slot 310 may have a structure for selectively allowing the pivot of the pivot member 300 according to the position of the lift member 200. For example, the pivot restricting slot 310 may include a pivot restricting section 311 for maintaining the pivot member 300 at the first inclination position. The pivot restricting section 311 may extend linearly in the lift direction TA. The pivot member 300 may be maintained at the first inclination position while the pivot restricting protrusion 301 is guided in the pivot restricting section 311. The pivot restricting slot 310 may be provided with an opening portion 312 such that the pivot restricting protrusion 301 may be deviated from the pivot restricting section 311 in order to allow the pivot member 300 to be pivoted from the first inclination position to the second inclination position as the lift member 200 approaches the bottom position. The opening portion 312 may be provided at the lower end portion of the pivot restricting section 311. When the lift member 200 approaches the bottom position, the pivot restricting protrusion 301 may face the opening portion 312 and the pivot member 300 may be in a state capable of being pivoted from the first inclination position to the second inclination position. [0095] A pinion-rack gear structure may be used a structure for pivoting the pivot member 300 to the first inclination position and the second inclination position. Referring to FIG. 22, the stacking tray apparatus of the present example may include a pinion gear portion 302 provided at the pivot member 300 and a rack gear 320 engaged with the pinion gear portion 302 to pivot the pivot member 300 as the lift member 200 approaches the bottom position. [0096] A process of pivoting the tray 3 to the first and second inclination positions will now be described with reference to FIGS.22 to 25. [0097] First, referring to FIG.22, the lift member 200 may be located at the top position or a suitable position between the top position and the bottom position for loading the paper P. The pivot restricting protrusion 301 may be located in the pivot restricting section 311. Thus, the tray 3 may be located at the first inclination position having a first angle. [0098] When the first driving motor M1 is driven in the forward direction, the forward driving force of the first driving motor M1 may be transmitted to the lift member 200 through the pinion 220 and the rack gear portion 203. The lift member 200 may be guided by the guide rail 210 and thus the lift member 200 may be lowered toward the bottom position. [0099] As illustrated in FIG. 23, when the lift member 200 approaches the bottom position, the pivot restricting protrusion 301 may be deviated from the pivot restricting section 311 and aligned with the opening portion 312. The pivot member 300 may be in a state capable of being pivoted. The rack gear 320 may be engaged with the pinion gear portion 302. When the lift member 200 is further lowered in this state, the pivot member 300 may be pivoted from the first inclination position to the second inclination position around the rotation shaft 202-1 by a combination of the rack gear 320 and the pinion gear portion 302. The pivot restricting protrusion 301 may be deviated from the pivot restricting slot 310 through the opening portion 312. As illustrated in FIG. 24, when the lift member 200 reaches the bottom position, the pivot member 300 may reach the second inclination position. [00100] When the first driving motor M1 is driven in the reverse direction in the state illustrated in FIG. 24, the lift member 200 may start to be raised. Then, by the combination of the rack gear 320 and the pinion gear portion 302, the pivot member 300 may be pivoted from the second inclination position to the first inclination position around the rotation shaft 202-1. As illustrated in FIG. 23, the pivot member 300 may be returned to the first inclination position immediately before the engagement between the rack gear 320 and the pinion gear portion 302 is ended as the lift member 200 is lifted. The pivot restricting protrusion 301 may be returned into the pivot restricting slot 310. When the lift member 200 is further raised in this state, the engagement between the rack gear 320 and the pinion gear portion 302 may be ended and the pivot restricting protrusion 301 may be guided in the pivot restricting section 311. Thus, the pivot member 300 may be maintained at the first inclination position. [00101] According to this structure, when necessary, the lift member 200 may be lowered to the bottom position to locate the tray 3 at the second inclination position. Thus, the paper P on the tray 3 may be easily accessed. The paper P saddle-stitched by the finisher 4 may be loaded into the tray 3. The saddle-stitched paper P may have a bound front end portion and a rear end portion thereof may be generally thicker than the front end portion thereof. In this case, the saddle-stitched paper P may be prevented from falling from the tray 3 by not lowering the lift member 200 to the bottom position and by lowering the lift member 200 up to immediately before the pivot member 300 is pivoted. Also, the lift member 200 may be lowered until the pivot member 300 reaches a suitable position between the first inclination position and the second inclination position. [00102] FIG. 26 is a schematic side view of an example of a stacking tray apparatus. FIG. 27 is a side view illustrating a state where a lift member 400 approaches a bottom position in the example of the stacking tray apparatus illustrated in FIG. 26. FIG. 28 is a side view illustrating a state where a lift member 400 reaches a bottom position in an example of the stacking tray apparatus illustrated in FIG.26. FIG.29 is a perspective view illustrating in detail a lift member 400. [00103] The stacking tray apparatus of the present example may be different from the example of the stacking tray apparatus illustrated in FIGS. 22 to 25 in that the lift member 200 and the pivot member 300 are integrated into a lift member 400 and the guide rail 210 and the pivot restricting slot 310 are integrated into a pivot guide slot 500. Also, in the stacking tray apparatus of the present example, a belt driving structure is used as a structure for lifting the lift member 400. [00104] Referring to FIGS.26 to 29, illustrated is a lift member 400 that may be lifted to the top position and the bottom position and may be pivoted from the first inclination position to the second inclination position after reaching the bottom position. The tray 3 may be supported by the lift member 400. [00105] As an example, the stacking tray apparatus may include a belt 453 for driving a first locking portion 455 in a lift section 431 for lifting the lift member 400 to the top position and the bottom position and a pivot section 432 for pivoting the lift member 400 located at the bottom position to the first inclination position and the second inclination position, a second locking portion 454 provided at the lift member 400 and having a slot shape cut in the lift direction TA in order for the first locking portion 455 to be inserted into the second locking portion 454, an upper guide roller 401 and a lower guide roller 402 provided at the lift member 400 to be separated in the lift direction TA, and an integrated guide slot 410 including a lift guide portion 411 into which the upper guide roller 401 and the lower guide roller 402 is inserted and which corresponds to the lift section 431 and pivot guide portion 412 which corresponds to the pivot section 432 and of which a side wall 413 in the discharge direction TB is inclined in the discharge direction TB in order for the lift member 400 to be pivoted to the first inclination position and the second inclination position in a state where the lift member 400 is located at the bottom position. [00106] The lift member 400 may be guided by the integrated guide slot 410 to be lifted to the top position and the bottom position. Referring to FIGS.26 and 29, the integrated guide slot 410 may extend in the lift direction TA. The lift member 400 may be provided with an upper guide roller 401 and a lower guide roller 402 inserted into the integrated guide slot 410. Two guide rollers 401 and 402 may be separated in the lift direction TA in order to allow the lift member 400 to be stably lifted in the lift direction TA. [00107] A belt driving structure may be used as a structure of a lift driving unit for lifting the lift member 400. Referring to FIG. 26, the lift driving unit may include a first shaft 451 and a second shaft 452 arranged to be separated in the lift direction TA, a belt 453 driven by being supported by the first shaft 451 and the second shaft 452, a first locking portion 455 provided at the belt 453, and a second locking portion 454 provided at the lift member 400 and coupled to the first locking portion 455. The lift driving unit may include a first driving motor M1. The first driving motor M1 may rotate any one of the first shaft 451 and the second shaft 452. The first shaft 451 may be adjacent to the top position, and the second shaft 452 may be adjacent to the bottom position. The first locking portion 455 may have a protrusion shape. The second locking portion 454 may have a slot shape into which the first locking portion 455 is inserted. According to this configuration, the first locking portion 455 may be inserted into the second locking portion 454 such that the lift member 400 may be maintained at a certain position between the top position and the bottom position. When the first driving motor M1 is rotated in the forward direction and thus the first locking portion 455 is lowered, the lift member 400 may be moved toward the bottom position by gravity. When the first driving motor M1 is rotated in the reverse direction, the first locking portion 455 may be raised to push the second locking portion 454 and thus the lift member 400 may be moved toward the top position. [00108] The lift member 400 may be pivoted to the first inclination position and the second inclination position. A movement section of the first locking portion 455 may include the lift section 431 and the pivot section 432. The belt 453 may move the first locking portion 455 to the lift section 431 and the pivot section 432. The lift section 431 may be a section for moving the lift member 400 to the top position and the bottom position. In the lift section 431, the lift member 400 may be lifted to the top position and the bottom position in the state of being located at the first inclination position. The pivot section 432 may be a section for moving the lift member 400 to the first inclination position and the second inclination position. In the pivot section 432, the lift member 400 may be pivoted to the first inclination position and the second inclination position in the state of being maintained at the bottom position. [00109] The integrated guide slot 410 may include a lift guide portion 411 corresponding to the lift section 431 and a pivot guide portion 412 corresponding to the pivot section 432. The lift guide portion 411 may have a slot shape extending in the lift direction TA. The pivot guide portion 412 may have a slot shape which extends in the lift direction TA and of which the side wall 413 in the discharge direction TB is inclined in the discharge direction TB to allow the lift member 400 to be pivoted to the second inclination position. [00110] The length of the lift guide portion 411 may be equal to or smaller than the distance between the two guide rollers 401 and 402. The upper guide roller 401 located thereabove may need to be deviated from the lift guide portion 411 such that the lift member 400 may be guided by the pivot guide portion 412 to be pivoted from the first inclination position to the second inclination position when the lift member 400 is located at the bottom position. Thus, the length of the pivot guide portion 412 may be equal to or greater than the distance between the two guide rollers 401 and 402. [00111] The second locking portion 454 may have a slot shape cut in the lift direction TA. The second locking portion 454 may have an upper end portion 454-1 and a lower end portion 454-2. In the lift section 431, the first locking portion 455 may contact the upper end portion 454-1 of the second locking portion 454. In the pivot section 432, the first locking portion 455 may be moved between the upper end portion 454-1 and the lower end portion 454-2. The distance between the upper end portion 454-1 and the lower end portion 454-2 may correspond to the length of the pivot section 432. The distance between the upper end portion 454-1 and the lower end portion 454-2 may be equal to the distance between the two guide rollers 401 and 402. As an example, the upper end portion 454-1 and the lower end portion 454-2 may be concentric with the guide rollers 401 and 402, respectively. According to this configuration, the lift member 400 may be rotated around a rotation shaft 402-1 of the guide roller 402 located therebelow. When the first locking portion 455 is substantially located at the lower end portion 454-2 of the second locking portion 454, the rotation shaft 402-1 of the guide roller 402 and the first locking portion 455 may become a coaxial state and thus may function as a pivot shaft of the lift member 400. [00112] A process of pivoting the tray 3 to the first and second inclination positions will be described with reference to FIGS.26 to 29. [00113] First, referring to FIG.26, the lift member 400 may be located at the top position or a suitable position between the top position and the bottom position for loading the paper P. The guide rollers 401 and 402 may be supported by the lift guide portion 411 of the integrated guide slot 410. The first locking portion 455 may support the upper end portion 454-1 of the second locking portion 454. Thus, the lift member 400 may be maintained at the first inclination position. When the first driving motor M1 is driven in the forward direction in this state, the first locking portion 455 may be lowered in the lift section 431. Then, the lift member 400 may be guided by the lift guide portion 411 to be lowered toward the bottom position. [00114] As illustrated in FIG.27, when the first locking portion 455 reaches the lower end portion of the lift section 431, the lift member 400 may reach the bottom position. The guide rollers 401 and 402 may be deviated from the lift guide portion 411 and located at the pivot guide portion 412. The first locking portion 455 may support the upper end portion 454-1 of the second locking portion 454. Thus, the lift member 400 may be maintained at the first inclination position. [00115] Subsequently, when the first driving motor M1 is driven in the forward direction, the first locking portion 455 may be lowered along the pivot section 432. The first locking portion 455 may be moved from the upper end portion 454-1 to the lower end portion 454-2 along the second locking portion 454. Even when the first locking portion 455 is separated from the upper end portion 454-1 of the second locking portion 454, because the guide roller 402 contacts the lower end portion of the pivot guide portion 412, the lift member 400 may be maintained at the bottom position. The lift member 400 may not be pivoted and may be maintained at the first inclination position until the first locking portion 455 does not reach the lower end portion 454-2 of the second locking portion 454. As illustrated in FIG. 28, when the first locking portion 455 reaches the lower end portion 454-2 of the second locking portion 454, the lift member 400 may be pivoted around the first locking portion 455 by gravity. When the guide roller 401 contacts the side wall 413 of the pivot guide portion 412, the lift member 400 may reach the second inclination position. [00116] When the first driving motor M1 is driven in the reverse direction in the state illustrated in FIG. 28, the first locking portion 455 may start to be raised along the pivot section 432. The first locking portion 455 may be moved from the lower end portion 454-2 to the upper end portion 454-1 of the second locking portion 454. As the first locking portion 455 is raised along the pivot section 432, the lift member 400 may be pivoted from the second inclination position to the first inclination position. The lift member 400 may be maintained at the bottom position until the first locking portion 455 contacts the upper end portion 454-1 of the second locking portion 454. As illustrated in FIG. 27, when the first locking portion 455 contacts the upper end portion 454-1 of the second locking portion 454, the lift member 400 may be returned to the first inclination position. The guide roller 401 may be aligned with the lift guide portion 411. [00117] Subsequently, when the first driving motor M1 is driven in the reverse direction, the first locking portion 455 may be raised along the lift section 431. The lift member 400 may be raised to the top position because the first locking portion 455 contacts the upper end portion 454-1 of the second locking portion 454. The guide roller 401 may enter the lift guide portion 411. When the first locking portion 455 approaches the upper end portion of the lift section 431, the guide roller 402 may enter the lift guide portion 411. When the first locking portion 455 reaches the upper end portion of the lift section 431, the lift member 400 may reach the top position as illustrated in FIG.26. [00118] According to this configuration, when necessary, the lift member 40 may be lowered to the bottom position and then pivoted to the second inclination position. Thus, the paper P on the tray 3 may be easily accessed. When the paper P saddle-stitched by the finisher 4 is loaded into the tray 3, the first motor M1 may be stopped to maintain the tray 3 at the first inclination position in a state where the lift member 400 is lowered to the bottom position. [00119] It should be understood that examples described herein should be considered in a descriptive sense and not for limitation. Descriptions of features within each example should be considered as available for other similar features in other examples. While examples have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope as defined by the following claims.