DESCRIPTION

DESKTOP MACHINE WITH A PAPER SUPPORT

Technical Field

The present invention relates to a paper pressing apparatus such as a stapler or a hollow punch, in which a bunch of papers is prevented from being bent at the time of a pressing processing such as a binding or a punching.

Background Art

For example, a stapler is a paper pressing apparatus equipped with a pressing mechanism, in which a base capable of mounting a plurality of stacked papers is provided with a clinching groove as a processing portion, an end portion of a bunch of said papers is set on the processing portion, and a binding processing is carried out by pressing the papers from above. The pressing mechanism binds the bunch pf papers by rotating a handle downward, thereby pressing a lower surface of a leading end of a magazine against the bunch of papers, driving a driver plate so as to pass through a driving portion of the magazine in a downward direction, driving a staple in the driving portion downward, and bending each leg of the staple penetrated through the bunch of papers by the

clinching groove, (see, e.g., JP-A-2005-138247) .

Similarly, a hollow punch is also a paper pressing apparatus equipped with a pressing mechanism, in which a base capable of mounting a plurality of stacked papers is provided with a blade receiving portion as a processing portion, an end portion of a bunch of said papers is set on the processing portion, and a punching processing is carried out by pressing the bunch of papers from above. In this case, the hollow punch is different from the stapler only in that a cylindrical punch blade is provided in place of the driver plate.

Meanwhile, in a paper pressing apparatus which processes a large number of sheets of paper, as its pressing mechanism itself increases in size, the whole apparatus also increases in size accordingly (see, e.g., JP-B-138248) . However, since such paper pressing apparatus is not used so often, it is required to make it compact so as not to take up space, for example at the time of storage. Therefore, a paper mounting portion of a base cannot be made sufficiently wide.

However, when processing a large number of sheets of paper at one time, a whole bunch of papers becomes heavy while the paper itself is of very low rigidity and easy to be bent. Therefore, when the bunch of papers is set on the processing portion that is not so wide, both sides

of the papers may bend and sag down. When the bunch of papers is processed in a bent state, in the case of the stapler, since the bent state is maintained, there is a problem in that a part of the papers may bulge or an end face of the papers may be displaced when the bunch of papers is flattened. In the case of the hollow punch, since a punching position is displaced, there is a problem in that an upper sheet of paper and a lower sheet of paper are not aligned when the paper is bound in a folder.

In either case, it is important that the bunch papers is flattened when it is mounted and set on the processing portion of the base.

Disclosure of the Invention

One or more embodiments of the present invention provides a paper pressing apparatus, in which a bunch of papers can be processed in a flat state.

According to one or more embodiments of the invention, a paper pressing apparatus includes: a base having a processing portion on which a bunch of papers to be processed is set; and a support arm provided on the base, wherein the base has a size capable of mounting a part of an edge portion of the bunch of papers when an end portion of the bunch of papers is set on the base,

and the support arm supports the edge portion of the bunch of papers which projects from the base in a flat state when the end portion of the bunch of papers is set on the base.

According to one or more embodiments of the invention, the support arm is formed such that an upper portion thereof and a lower portion thereof are symmetric with respect to a center line of the support arm.

According to one or more embodiments of the invention, a scale providing an indication of a setting position of the bunch of papers is formed on the support arm.

According to one or more embodiments of the invention, the support arm is provided on the base in such a way as to be horizontally pivotable.

According -to one or more embodiments of the invention, the paper pressing apparatus further includes a positioning member which positions the end portion of the bunch of papers to be processed, wherein the positioning member is provided on the base so as to be slidable along a longitudinal direction of the base, and an opening is formed on the positioning member into which a corner of the bunch of papers can be inserted.

According to one or more embodiments of the invention, the support arm includes: a proximal end

portion provided pivotally on the base; and an edge side support portion extending along a side edge portion of the base from the proximal end portion wherein a support arm attachment portion, to which the proximal end portion of the support arm is attached, is formed on the base.

According to one or more embodiments of the invention, the proximal end portion includes: a pivot formed at a center of the proximal end portion; and a protrusion formed on a circumference of the pivot, wherein a pivot hole, which engages with the pivot, is formed on the support arm attachment portion, and a plurality of engagement holes, which engages with the protrusion, is formed on the support arm attachment portion along a circumference of the pivot hole.

According to one or more embodiments of the invention, a guide groove is further formed on the support arm attachment portion, wherein the guide groove guides the pivot to the pivot hole when attaching the proximal end portion of the support arm to the support arm attachment portion.

According to one or more embodiments of the invention, an annular groove is further formed on the lower surface of the support arm attachment portion, wherein the annular groove contains the protrusion therein.

According to one or more embodiments of the invention, the support arm further includes an inner side support portion which supports inner side of the edge portion of the bunch of papers from below, wherein the inner side support portion extends along a front edge portion of the base from the edge side support portion.

According to one or more embodiments of the invention, a cutout portion is formed at an end of the inner side support portion.

According to one or more embodiments of the invention, an arm receiving portion is formed on the side edge portion of the base in a convex shape in cross- section, on which a engagement recess is formed, the edge side support portion is formed in a concave shape in cross-section, inside which a engagement projection is formed, and the engagement projection- engages with the engagement recess so that the edge side support portion is fitted in the arm receiving portion.

According to one or more embodiments of the invention, a gap into which a finger tip can be inserted therein is formed between an upper surface of the edge side support portion and an upper surface of the base when the edge side support portion is fitted in the arm receiving portion.

According to one or more embodiments of the

invention, the support arm is provided in such a way as to be able to be retracted into or drawn out from the base .

According to one or more embodiments of the invention, at least a part of an upper surface of the support arm and an upper surface of the base are formed so as to be on a same plane.

According to one or more embodiments of the invention, the support arm includes an inner side support portion which supports inner side of the edge portion of the bunch of papers from below.

According to one or more embodiments of the invention, the paper pressing apparatus further includes a pinion disposed inside the base, wherein a rack is formed on the support arm, and the rack engages with the pinion. - - - - .

According to one or more embodiments of the invention, the support arm employs a pantograph mechanism so that the support arm can enter or come out from the base.

According to one or more embodiments of the invention, the support arm is formed from a leaf spring material which is in a coiled state when contained in the base, and is made straight when used.

According to one or more embodiments of the

invention, as the base is provided in a size such that an edge portion of part of paper can be mounted when an end portion of the paper is set on the processing portion, the base has such a size that the paper bends on both sides of the processing portion. However, the support arm is provided on the base, and an edge portion of the paper, which projects from the base when the paper is mounted on the base, is supported flat from below by the support arm. Consequently, when the pressing mechanism is operated, the bunch of papers is processed evenly from an upper surface side to a lower surface side. For this reason, no distortion or deformation occurs, and the processing will be well-finished.

According to one or more embodiments of the invention, in every case, as the whole support arm is approximately fit within a width of the base, the paper pressing apparatus can be made compact.

According to one or more embodiments of the invention, it is possible to slide the positioning member and accurately determine a paper processing position. At the same time, even in the event that a mounting position of the paper changes, such as when inserting a corner of the bunch of papers in the opening and carrying out a pressing processing (a stapling, a punching) with respect to the corner of the bunch of papers, since the support

arm is provided in such a way as to be horizontally pivotable, by randomly selecting a pivotal angle of the support arm in accordance with a change in the mounting position of the paper, the edge portion of the bunch of papers can be always supported in a good condition.

According to one or more embodiments of the invention, as a base is provided with support arms which can support paper in conjunction with the base, a part of the paper is mounted on the base and another part projecting from the base is supported by the support arms from an underside while, as a paper center side of an edge portion of the another part is supported by inner side support portions of the support arms from the underside, the paper is supported flat from below. Consequently, when the pressing mechanism is operated, the paper is -processed evenly from the upper end to,--the- lower end. For this reason, no distortion or deformation occurs, and the processing will be well-finished.

According to one or more embodiments of the invention, as the support arms are provided in such a way as to be able to be retracted into or drawn out from the base, and at least part of an upper surface of each of the support arms is provided in such a way as to, in a retracted condition, form approximately the same plane with an upper surface of the base in conjunction with the

base, as well as the base being able to be configured compactly _/ the paper can be supported widely on the same plane.

According to one or more embodiments of the invention, as a cutout portion is formed at a front edge side end of each of the support arms, the support arm can be easily drawn out by hooking a finger on the cutout portion.

According to one or more embodiments of the invention, which is pivotally mounted on the base, and an edge side support portion, which is extended from the proximal end portion and along a side edge of the base, in which the inner side support portion is extended from the edge side support portion and along a front edge of the base, the whole length of the support arms which supports the paper can -be made maximal.

According to one or more embodiments of the invention, as a configuration is such that the support arms of squared U-shape in cross-section are retracted and fitted in arm receiving portions having a laterally convex shape in cross-section on both left and right edges of the base, the support arms and the base appear integral in a retracted condition. Also, as the whole support arms fit within a width of the base, the apparatus can be made compact. Furthermore, as

engagement portions which can engage with each other are formed in areas in which, in a retracted condition, the arm receiving portions make vertical contact with the support arms, a retraction of the support arms can be maintained in a good condition.

According to one or more embodiments of the invention, as a click mechanism is provided in support arm attachment portions formed in the base and the support arms and, at the time of a pivotal movement, the support arms can be retained at a prescribed open angle, a corner binding also becomes possible, and various binding operations can be reliably carried out.

According to one or more embodiments of the invention, as a scale providing an indication of a binding position of the paper is formed on each of the support arms, -a- binding position- - can be- accurately obtained.

According to one or more embodiments of the invention, as a gap of such an extent that a finger tip can be inserted therein is formed in a portion between the upper surface of the base and the upper surface of each of the support arms, the support arms can be easily drawn out by hooking a finger in the gap.

According to one or more embodiments of the invention, as the support arms are each formed in such a

way that the upper and lower portions are symmetric with respect to a center line, the left and right support arms can be interchanged.

Brief Description of the Drawings

Fig. 1 is a perspective view of a stapler according to a first embodiment of the invention;

Fig. 2 is a longitudinal sectional view of the stapler;

Fig. 3 is an exploded perspective view of a base and a support arm;

Fig. 4 is a sectional view of the support arm and a hinge portion;

Fig. 5 is a perspective view of the stapler showing a condition in which the support arm is opened; and

Fig,- 6A is a plan view schematically showing a support arm according to a second embodiment of the invention.

Fig. 6B is a plan view schematically showing a support arm according to a third embodiment of the invention.

Fig. 6C is a plan view schematically showing a support arm according to a fourth embodiment of the invention.

Fig. 7 is a perspective view of a stapler according

to a fifth embodiment of the invention.

Fig. 8 is a perspective view of a condition in which support arms are drawn out.

Fig. 9 is an exploded perspective view of the stapler.

Fig. 10 is a plan view of a front portion of a base.

Fig. 11 is a sectional view along line X-X of Fig. 10.

Fig. 12 is a sectional view along line Y-Y of Fig. 10.

Fig. 13 is a sectional view along line Z-Z of Fig. 10.

Fig. 14 is a perspective view of a condition in which a corner binding is carried out.

Fig. 15 is a perspective view of a stapler according to a sixth embodiment of the invention. • —

Fig. 16 is a perspective view of a stapler according to a seventh embodiment of the invention.

Best Mode For Carrying Out the Invention Embodiment 1

Fig. 1 is a perspective view of a stapler according to the first embodiment of the invention, and Fig. 2 is a longitudinal sectional view of the stapler. In the same figures, reference numeral 1 depicts a base. A paper

mounting surface Ia, on which paper is mounted, is formed on one side of the base 1, and a clinching groove (a processing portion) 2 is provided in the middle of the base 1. A first support plate 3 and a second support plate 4 stand at an end of the other side of the base 1. As a pressing mechanism, a magazine 6 and an driver arm 7 are pivotably provided on a first support shaft 5 provided on the first support plate 3, and an handle 10, which drives the driver arm 7, is pivotably provided on a second support shaft 8 provided on the second support plate 4.

The magazine 6 has a space inside which connected U- shaped staples S are contained, and a driving portion 12 is opened at a leading end of the magazine 6. A staple pusher 13, which presses the connected staples S toward the driving portion 12, is disposed inside the magazine 6.

A driver plate 14 is retained at a leading end of the driver arm 7. A leading end of the driver plate 14 engages with an end of the magazine 6 above the driving portion 12.

Also, the handle 10, being for driving the driver arm 7, is formed by integrally connecting two long and short handle members 10a and 10b, and has an outer side covered with a cover 10c made of resin. A guiding groove 15, which winds in a gentle S-shape, is formed in each

side surface of the short handle member 10b. A drive shaft 16 projecting from both sides of the driver arm 7 engages in the guiding grooves 15. In this way, a force multiplication mechanism is configured by increasing a ratio of a distance from a fulcrum p of the handle 10 to a working point q and a distance therefrom to a power point r.

When the handle 10 is pressed from top down and pivoted, the driver arm 7 and the driver plate 14 are driven downward together with the drive shaft 16 engaged in the guiding grooves 15, and a lower face of the driving portion 12 at the leading end of the magazine 6 is pressed against the top of bunch of papers 100. Furthermore, by causing the driver plate 14 of the driver arm 7 to pass through the driving portion 12 in a downward direction, a head staple - Sl supplied -to . the leading end of the magazine 6 is driven from the driving portion 12. Then, ends of the staple pass through the bunch of papers 100 mounted on the paper mounting surface Ia and, furthermore, are pressed against the clinching groove 2 and bent, thereby making it possible to bind the bunch of papers 100. When the binding is finished, as well as the magazine 6, the driver arm 7 and the handle 10 being restored to the initial condition in Fig. 1 by a first spring 17 and a second spring 18, the staples are

fed one staple's worth of distance in the driving portion 12 by the stapler pusher 13, thereby making the next binding ready.

According to the thus configured stapler, by employing the force multiplication mechanism, even though a force depressing the handle 10 is small, it is possible to obtain a far larger drive force than a force by which the driver plate 14 is depressed directly using the driver arm 7, and to bind a large number of sheets of bunch of papers 100.

The base 1 is formed in a size such that an edge portion of part of the bunch of papers 100 can be mounted when an end portion of the bunch of papers 100 is set on the processing portion. The reason is that the base 1 is made unobstrusively compact in size when the stapler is not- in use; . . .. - . ... .

Next, as shown in Fig. 1, the base 1 is provided with support arms 20 which, when the bunch of papers 100 is mounted thereon, can support the edge portion of the bunch of papers 100 flat from below in cooperation with the base 1. That is, the support arms 20 are provided in such a way as to be pivotally openable and closeable, one on each side of the paper mounting surface Ia of the base 1. The support arms 20, as well as being formed in a squared U-shape in cross section as shown in Fig. 3, each

have side pieces 20a and 20b, at respective leading ends of which engagement projections 22 are formed in opposed positions, and in respective proximal end portions of which circular hinge portions 23 and 24 are formed. Each pair of hinge portions 23 and 24 has central pivots 25 and projections 26, which are provided close to the peripheries, formed in opposed positions. Correspondingly, arm receiving portions 27 for the support arms 20 are formed, one on each side of the paper mounting surface Ia of the base 1. The arm receiving portions 27 each have a shape in which an upper, lower and outer surface of the base 1 are recessed in conformity to the cross section of the support arm 20. Engagement recesses 28 and 29 are formed on upper and lower surfaces at a leading end of each of the arm receiving portions 27, and a support-- arm attachment portion 30 formed on an upper surface in a proximal end portion of each of the arm receiving portions 27 is formed into a circular arc. A pivot hole 32 is formed in the center of the support arm attachment portion 30, and engagement holes 21 are formed on a circumference around the pivot hole 32. Correspondingly, as shown in Fig. 4, a pivot hole 33 is formed in the center of a support arm attachment portion 31 formed on a lower surface at the proximal end portion, while an annular groove 35 for

containing the projection 26 is formed in a circumferential direction corresponding to the engagement holes 21.

In the configuration described heretofore, when attaching the support arms 20 to the base 1, by pressing the upper and lower hinge portions 23 and 24 at the proximal end portion of each of the support arms 20 against the proximal end portion of each of the support arm receiving portions 27, the pivots 25 are engaged with the pivot holes 32 and 33 of the upper and lower support arm attachment portions 30 and 31 of the base 1, thus fitting the support arms 20 into the arm receiving portions 27 from the outside. By this means, the support arms 20 are placed in a closed condition, in which the support arms 20 are not freely opened with the engagement projections 2-2 -at -leading ends thereof- engaged in. the- engagement recesses 28 and 29 of the arm receiving portions 27. Also, in the closed condition, the upper and lower surfaces 20a and 20b and the outer side surface of each of the support arms 20 become flush respectively with the upper, lower and outer side surfaces of the base 1. Furthermore, in the closed condition, a gap 36 of such a size that a finger can be inserted therein is formed between the leading end of each of the support arms 20 and each of the arm receiving portions 27. Then,

the support arms 20 become pivotally openable and closeable in a horizontal direction around the pivots 25 and, when opening, open up to both sides of the clinching groove 20 in such a way as to form a 180° angle.

The support arms 20, when pivoting, are positioned at each fixed angle by a click mechanism which brings the projections 26 on the upper surfaces into engagement and disengagement with the engagement holes 21.

According to the configuration described heretofore, when binding the bunch of papers 100, as shown in Fig. 5, the support arms 20 are pivoted and opened in such a way as to form a 180° angle. By this means, as flush portions open up to both right and left sides of the clinching groove 2, the bunch of papers 100, when mounted on a binding base, is supported flat without bending on both -sides of the -clinching groove 2. - When a binding operation is carried out by depressing the handle 10 in this condition, the bunch of papers 100 is bound evenly from its upper end to its lower end by a staple. For this reason, no distortion or deformation occurs, and the binding is well-finished.

In the support arms 20 for preventing the bunch of papers 100 from bending, a structure of the hinge portions 23 and 24 is made vertically symmetrical. By this means, there is an advantage that, by using the

support arms 20 upside down, it is possible to interchange the right and left support arms 20.

Contrarily, a structure of the attachment portions 30 and 31 of the support arms 20 is made vertically asymmetrical. The upper support arm attachment portions 30 each have the engagement holes 21 formed at fixed spaced intervals in a circumferential direction, while the lower support arm attachment portions 31 each have the annular groove 35 formed in place of the engagement holes 21.

According to the configuration described heretofore, as the lower surfaces of the lower hinge portions 24 of the support arms 20 are arranged to configure a lower end face of the base 1 in such a way that, when the stapler is installed on an upper surface of an office desk or the like, the support arms 20 in the open condition are supported on an installation surface 37 (refer to Fig. 4), the lower surfaces of the lower hinge portions 24 abut against the installation surface 37. In this case, as the projections 26 of the lower hinge portions 24 of the support arms 20 are contained in the annular grooves 35 of the lower support arm 20 attachment portions, when the support arms 20 are pivotally opened and closed, as well as the support arms 20 operating smoothly with their pivotal centers retained, the lower hinge portions 24 of

the support arms 20 are prevented from bending and moving vertically.

Contrarily, the upper hinge portions 23 of the support arms 20 move upward each time the projections 26 cross the engagement holes 21. By this means, although the support arms 20 are positioned at each fixed angle, in the event that the same mechanism is employed for the lower support arms 20, as the lower hinge portions 24 of the support arms 20 bend downward each time the projections 26 cross the engagement holes 21, which interferes with the installation surface and increases a resistance, there is a possibility that an opening and closing operation of the support arms 20 cannot be smoothly carried out. For this reason, a configuration is such that the annular grooves 35 are formed, instead of the- engagement holes 21, on the support arm attachment portions 31 on the lower surface side of the base 1 and, by the projections 26 moving along the annular grooves 35 when the support arms 20 pivot, the support arms 20 are retained with the pivots 25 as their pivotal center. Consequently, as well as a pivoting always being able to be smoothly carried out due to the structure of the lower support arm attachment portions, a positioning can also be carried out at each fixed angle by the click mechanism of the upper support arm attachment portions.

As shown in Fig. 1, a positioning member 45, which, being slidably provided along a longitudinal direction of the base 1, determines a paper end portion position when pressing and processing the bunch of papers 100, is disposed on the base 1, and the positioning member 45 is formed, in an area corresponding to the processing portion of the base 1, with an opening 46 which opens toward its top and in which a corner of the paper can be inserted. Also, a mark 9 providing an indication when binding a corner of the paper is formed on each side of the clinching groove 2.

According to this positioning configuration, it is possible to slide the positioning member 45 and accurately determine a processing position of the bunch of papers 100. At the same time, even in the event that a mounting position of the bunch of papers 100 changes, such as when inserting a corner of the bunch of papers 100 in the opening 46 and carrying out a pressing processing (a stapling, a punching) with respect to the corner of the bunch of papers 100, as the support arms 20 are provided in such a way as to be horizontally pivotable, by randomly selecting a pivotal angle of the support arms 20 in accordance with a change in the mounting position of the bunch of papers 100, the edge portion of the bunch of papers 100 can always be

supported in a good condition.

As shown in Figs. 1 and 5, by forming a plurality of marker grooves 47a, 47b and 47c on each of the support arms 20, the marker grooves 47a, 47b and 47c can be utilized as positioning marks when mounting the bunch of papers 100. Embodiment 2

Meanwhile, the configuration of the support arms 20 is not limited to the first embodiment described heretofore. For example, as shown in Fig. 6A, it is also acceptable to configure in such a way that the support arms 20 are normally retracted inside the base 1 and, at the time of a binding, are drawn out and extended. For example, it is also acceptable to configure in the following way. That is, using a rack and pinion mechanism, racks 39 are formed on opposed- sides of two support arms 38, and both racks 39 are engaged with a common pinion 40, whereby, when one of the support arms 38 is drawn out to one side of the clinching groove 2, the other also automatically moves to the other side of the clinching groove 2, thus supporting the bunch of papers 100 from below by means of the drawn-out support arms 38. It is sufficient that, when the stapler is not in use, by pushing one of the support arms 38 into the inside of the base 1, the other is also retracted into

the base 1, or the support arms 38 are pushed in to such an extent that they are slightly exposed to the outside. Embodiment 3

Also, as shown in fig. 6B, it is also acceptable to configure in such a way that, using a pantograph mechanism, a support arm 41 is attached in such a way as to be able to enter or come out from the base 1 and, when not used, is contracted while, when used, the support arm

41 is extended to support the bunch of papers 100 from below.

Embodiment 4

Furthermore, as shown in Fig. 6C, it is also acceptable to configure in such a way that support arms

42 are formed from a band-like leaf spring material for use in a tape measure or the like, are retracted in the -base 1 in a coiled state and, when -used, one end- of them- is drawn out and made straight.

Embodiment 5

Fig. 7 is a perspective view of a stapler according to a fifth embodiment of the invention. Descriptions of the same members as those in the above embodiments are omitted. As shown in Fig. 8, support arms 20, which, of a remaining portion of the bunch of papers 100 projecting from the base 1 when mounted thereon, can support an edge portion 101 of the bunch of papers 100 flat from below in

conjunction with the base 1, are provided in such a way as to be able to be attachable and removable, and openably and closeably pivotal.

As shown in Fig. 9, the support arms 20 each include a proximal end portion 20c pivotably mounted on the base 1, an edge side support portion 2Od extended from the proximal end portion 20c and along a side edge Ic of the base 1, and an inner side support portion 2Oe extended from the edge side support portion and along a front edge of the base. Reference numeral 2Of depicts an upper surface of the edge side support portion 2Od and the inner side support portion 2Oe.

The support arms 20 are provided in such a way as to be able to be retracted into or drawn out from the base 1 by a pivotal movement. That is, as shown in Figs. 9 to 12, a vertically symmetrical arm receiving -portion 27 -of laterally convex shape in cross-section is formed at a front of the paper mounting surface Ia of the base 1. Then, a support arm attachment portion 30 approximately semicircular in plan is formed at an end of the arm receiving portion 27 corresponding to each side of the clinching groove 2 of the base 1. A pivot hole 32 is formed in a center of each of upper and lower surfaces of the support arm attachment portion 30, and a plurality of engagement holes 21 is formed on the upper surface of the

support arm attachment portion 30 along a circumference of one circle. Furthermore, guide grooves 50 are formed inclined on an outer side of the support arm attachment portion 30. An annular groove 35 (refer to Fig. 11) of approximately the same width and the same radius is formed on the lower surface of the support arm attachment portion 30.

In contrast, an upper hinge portion 23 and a lower hinge portion 24, being of a size by which they fit in the support arm attachment portion 30, are formed in the proximal end portion 20c of the support arm 20. Pivots 25 are formed in central portions of a lower surface of the upper hinge portion 23 and an upper surface of the lower hinge portion 24, and a plurality of projections 26 is formed in positions which correspond to each other on the lower- surface of upper hinge portion 23--and-the -upper surface of the lower hinge portion 24, along a circumferential direction of one circle. A number of projections 26 and a radius of a circle along which they are disposed correspond to a number of engagement holes 21 and a radius of a circle along which they are disposed. Also, the edge side support portion 2Od and the inner side support portion 2Oe of the support arm 20, being integrally molded, are bent in an approximately L shape, and are formed in a laterally concave shape in cross-

section which fits the arm receiving portion 27 of the base 1. Then, the support arm 20 is generally formed in such a way that the upper and lower portions are symmetrical with respect to a center line C.

When the proximal end portion 20c of the support arm 20 is pivotally mounted on the support arm attachment portion 30 of the base 1, it is pushed in such a way as to sandwich the support arm attachment portion 30 between its upper hinge portion 23 and lower hinge portion 24. At this time, as shown in Fig. 12, the pivots 25 of the support arm 20 are guided along the guide grooves 50 of the support arm attachment portion 30, and the upper and lower pivots 25 engage smoothly in the pivot holes 32 of the support arm attachment portion 30. By this means, the support arm 20 is pivotally mounted on the support arm attachment portion 30 in- such a- way th-at it is horizontally pivotable about the pivots 25. By widening the upper hinge portion 23 and the lower hinge portion 24, the support arm 20 can be easily removed from the base 1.

In this way, the support arms 20 are provided in such a way as to be able to be retracted into or drawn out from the base 1. At the time of retraction, a configuration is such that the edge side support portion 2Od and the inner side support portion 2Oe of the support arm 20 fit the arm receiving portion 27 formed on the

side edge Ic and the front edge Id of the base 1, and such that the whole upper surface 2Of of the support arm 20 forms approximately the same plane with the paper mounting surface Ia on the upper surface of the base 1 in conjunction with the base 1 as shown in Fig. 7. Then, at the time of retraction, as shown in Fig. 11, the projections 26 of the support arm 20 are retained in a position in which they engage in the engagement holes 21 of the support arm attachment portion 30 but, when the support arm 20 is drawn outward and pivoted, the upper hinge portion 23 of the support arm 20 is deformed upward, and the projections 26 disengage from the engagement holes 21, engage in the next engagement holes 21, and are retained in the position. When the support arm 20 is further pivoted, in the same way, the projections 26 disengage from- the engagement holes 21, - cross these engagement holes 21, and engage in the next engagement holes 21. In this way, as a click mechanism, in which a resistance varies each time the projections 26 cross the engagement holes 21, is configured in the base 1 and the support arm attachment portion 30 of the support arm 20, at the time of engagement, the support arm 20 cannot pivot freely and can be retained at a prescribed open angle. It is preferable that the open angle is set to 0° at the time of retraction, 45° in an intermediate

position and a maximum angle of 90°.

As the projections 26 on the lower hinge portion 24 of the support arm 20 engage in the annular groove 35 on the lower surface of the support arm attachment portion 30, when the support arm 20 pivots, the projections 26 always move while fitting in the annular groove 35, thus preventing the lower hinge portion 24 from being bent and deformed downwardly of the lower surface of the base 1 as the upper hinge portion 23 is. Consequently, the base 1 is prevented from hovering away from an installation surface 37 at the time of a pivotal movement of the support arm 20, as it is possible to smoothly operate a pivotal movement of the support arm 20.

Next, as shown in Figs. 8 and 13, engagement recesses 51 are formed, one on each of upper and lower -surfaces of the base 1 in the middle of the arm receiving portion 27. A leading groove 52 opening to the outer side of the arm receiving portion 27 is continuously formed in the lower engagement recess. Meanwhile, engagement projections 53, which can engage in the engagement recesses 51, are formed in positions which, being located in the middle of the edge side support portion 2Od of the support arm 20, correspond to the engagement recesses 51 and leading groove 52 of the base 1. By this means, when the support arm 20 is retracted,

the engagement projections 53 engage in the engagement recesses 51. At this time, the lower engagement projection 53 of the edge side support portion 2Od is smoothly guided from the leading groove 52 of the arm receiving portion 27 and engages in the engagement recess 51. As an engagement portion (the engagement recesses 51 and the engagement projections 53) is formed in an area in which the arm receiving portion 27 makes vertical contact with the edge side support portion 2Od, the support arm 20 is retained in a retracted condition and prevented from pivoting freely.

Furthermore, a semicircular cutout portion 54 is formed at a leading end of the inner side support portion 2Oe of the support arm 20 on each side. It is preferable that the cutout portion 54 is about half big enough for a finger tip -to be i-nserted therein. When- the support arms- 20 are retracted, a space of such a size that a finger tip can be inserted therein is formed by the cutout portions 54 of the support arms 20 on both sides. In this way, it is preferable that the leading ends of the support arms 20 on both sides are disposed abutted when retracted.

As shown in Fig. 7, a gap 36 of such an extent that a finger tip can be inserted therein is formed in a corner between the upper surface Ia of the base 1 and the

upper surface 2Of of the retracted support arm 20.

A scale groove 47 providing an indication of a binding position of the bunch of papers 100 is formed on the edge side support portion 2Od of the support arm 20.

Next, when using the stapler of the heretofore described configuration, first, a finger is inserted in the gap 36 formed in the corner of the base 1 in the condition shown in Fig. 7, and the support arm 20 on each side is drawn outward in such a way as to push an inner side of the support arm 20, and is pivoted. At this time, it is also acceptable to pivot the support arm 20 by hooking a finger on the cutout portion 54 at the end of the support arm 20. Each support arm 20 is pivoted through 90° as shown in Fig. 8 and retained at the open angle and, after a position of the positioning member is determined, the edge portion 101 -of the bunch- of papers 100 is mounted on the paper mounting surface Ia and the upper surface 2Of of the support arm 20, and set in position. As the support arm 20 is configured in such a way as to form approximately the same plane with the paper mounting surface Ia in conjunction with the base 1, a bunch of papers 100 mounting area increases by an amount by which the support arms 20 are drawn to both sides, and a portion of the bunch of papers 100 projecting from the base 1, meaning that a portion of the

bunch of papers 100 surrounding the clinching groove 2 is retained flat. On this occasion, the edge side support portion 2Od of the support arm 20 supports the edge portion 101 of a portion of the bunch of papers 100 projecting from the base 1 from below. Also, as the inner side support portion 2Oe supports a paper center side of the edge portion of a portion of the bunch of papers 100 projecting from the base 1 from an underside, it is possible to support the bunch of papers 100 in a more stable and flatter position than in a case in which only an edge portion of the bunch of papers 100 projecting from the base 1 is supported.

By, in this condition, depressing the handle 10, driving the driver plate 14 and driving a staple, ends of the staple pass through the bunch of papers 100 mounted on the- paper- - mounti-ng- surface Ia and, furthermore,- -by pressing the ends against the clinching groove 2 and bending them, the bunch of papers 100 can be bound. When the binding is finished, as well as the handle 10, the driver arm 7 and the magazine 6 being restored to the initial condition in Fig. 7 by a not-shown spring, the connected staples are fed one staple's worth of distance in the driving portion 12, thereby making the next binding ready. As the bunch of papers 100 is bound in a flat state, the bunch of papers 100 is bound evenly from

a top sheet to a bottom sheet without the top and bottom sheets of bunch of papers 100 being displaced. For this reason, no distortion or deformation occurs, and the binding will be well-finished.

When binding two places, by adjusting a side edge of the paper to the scale groove 27 of the support arm 20, binding positions from both side edges can be accurately made the same.

Also, when binding a corner of the bunch of papers 100, it is sufficient that each support arm 20 is pivoted through 45 degrees as shown in Fig. 14. At this open angle, the support arms 20 are retained by the click mechanism. As well as a corner of the bunch of papers 100 being inserted in the opening 46 of the positioning member 45, the edges 101 and 102 intersecting at the corner are -mounted on the support arms -20. - As a -portion projecting from the base 1 is supported by the support arms 20, the bunch of papers 100 is retained flat. On this occasion too, as the inner side support portions 2Oe support a paper center side of an edge portion of the bunch of papers 100 projecting from the base 1 from the underside, it is possible to support the bunch of papers 100 in a stable position. Furthermore, both edges intersecting at a corner of the bunch of papers 100 are adjusted to marks 9 on both sides of the clinching groove

2. In this condition, by depressing the handle 10 and carrying out a binding operation, the bunch of papers 100 can be bound from a top sheet to a bottom sheet without the top and bottom sheets being displaced.

After the binding operation is finished, it is sufficient that support arms 20 on both sides are retracted into the arm receiving portions 27 of the base 1. At this time, as engagement projections 53 of the support arms 20 engage in the engagement holes 51 of the arm receiving portions 27, the support arms 20 are retained in a retracted condition and prevented from pivoting freely.

According to the stapler configuration, as the support arms 20 each include the proximal end portion 20c pivotally mounted on the base 1, the edge side support portion 2Od -extended from the proximal end portion.- 20c and along the side edge portion Ic of the base 1, and the inner side support portion 2Oe extended from the edge side support portion 2Od and along the front edge portion Id of the base 1, the whole length of the support arms 20 supporting the bunch of papers 100 can be made maximal.

Also, as the support arms 20 are configured in such a way as to, in a retracted condition, form approximately the same plane with the paper mounting surface Ia in conjunction with the base 1, they appear to be integral

with the base 1, and the whole of them is fit within a width of the base 1, meaning that, as well as the stapler being able to be configured compactly, the bunch of papers 100 can be widely supported on the same plane.

In addition, as the support arms 20 are formed in such a way that the upper and lower portions are symmetric with respect to the center line C, there is an advantage that, by using the support arms 20 upside down, it is possible to interchange parts of the right and left support arms 20. Embodiment 6

It is also acceptable that, as shown in Fig. 15, the support arms 20 are each configured in such a way as to combine a shaft-like edge side support portion 55 and a plate-like inner side support portion 2Oe provided at a -leading end thereof.- - In this case, a- arm- recei-ving portion of a base 1, into which the edge side support portion 55 is retracted, is formed in a groove shape in which the edge side support portion 55 is fit.

In this way, it is also acceptable to configure in such a way that an upper surface 2Of of the inner side support portion 2Oe forms approximately the same plane with a paper mounting surface Ia on an upper surface of the base 1 in conjunction with the base 1.

According to this configuration too, it is possible

to obtain ^' the same advantageous effect as that shown in the embodiment 5. Embodiment 7

Fig. 16 shows another mode in which support arms 20 are provided in such a way as to be able to be retracted into or drawn out from a base 1. In the same figure, the support arm 20 on each side is formed in an L-shape by an edge side support portion 2Od and an inner side support portion 2Oe, and the edge side support portion 2Od of each of the left and right support arms 20 is provided in such a way as to be able to be retracted into or drawn out from the base 1. Then, a configuration is such that, by the edge support portion 2Od sliding in a left and right direction, the support arm 20 can be retracted into or drawn out from the base 1. In this case too, an upper surface of the support arm 20 is configured -in suc-h a -way as to form approximately the same plane with a paper mounting surface Ia of the base 1 in conjunction with the base 1. Also, a gap 36 of such an extent that a finger tip can be inserted therein is formed between the upper surface of the base 1 and the retracted inner side support portion 2Oe.

According to this configuration too, it is possible to obtain the same advantageous effect as that shown in the embodiment 5.

Further, also in the embodiments 6 and 7, the support arms are each formed in such a way that the upper and lower portions are symmetric with respect to the center line. Also, descriptions of the same members as those in the embodiment 5 are omitted.

While there has been described in connection with the embodiments of the present invention, it will be obvious to those skilled in the art that various changes and modification may be made therein without departing from the present invention. It is aimed, therefore, to cover in the appended claim all such changes and modifications as fall within the true spirit and scope of the present invention.

The subject patent application is based on a Japanese patent application No. 2005-326469 filed on November 10, 2005, and Japanese patent application No. 2006-128287 filed on May 2, 2006, the contents of which are incorporated herein by reference.

Industrial Applicability

The present invention enables a paper pressing apparatus to process a bunch of papers in a flattened state. The paper pressing apparatus to which the present invention is applied is not limited to a stapler. For example, the paper pressing apparatus may be a hollow

punch in which the bunch of papers is required to be supported in a flat state during punching.