TECHNICAL FIELD

[001] The present subject matter generally relates to a feeder. More specifically, the subject matter relates to a sheet feeder and a method of making the feeder. The subject matter also relates to a guide of the feeder customized to neutralize static charges on sheet.

BACKGROUND

[002] High speed operation and minimal downtime is the key to success in the printing and post printing production business. One of the bottlenecks in speeding up the operation is the ability to quickly feed a sheet for processing/printing. Not only the present day printing technology greatly depend on the static charges for printing but the sheets production technology has evolved and more and more synthetic sheets are now being used. These synthetic sheets have extremely high affinity for static charge. Therefore the shear act of stacking sheets or moving sheets generates large amount static charge which causes them to stick to one another. To cleanly pick a sheet and feed it for processing requires that the static charge is appropriately neutralized and/or handled.

[003] One of the methods for handling the static charge build up on sheets is to blow air on top of the sheet prior to picking the sheet up. This method is however not most effective method for two reasons. First that the strength of blow of air must be

meticulously selected such that it is not high enough to dislocate the sheet from its position and must be high enough that it separates a sheet from the rest of the stack of sheets. This method often fails and results in paper jam or mis-feeding of sheets. Furthermore, this method uses rather a brute force to separate the sheet. The brute force must be high enough to counter the attractive force of the static charge that causes the sheets to stick together. Because this method uses brute force, chances of dislocation of sheet from its desired position is highly likely, this often results in mis-feed of sheets.

[004] The US Patent document 5402304A of Dirk S. Smith (hereinafter“Smith”) discusses an apparatus for eliminating static build-up in paper (or plastic) stock used within paper handling machines. Shown in FIG. 1, the apparatus provides an anti- static air enhancer cartridge with an airstream. The enhanced airstream is directed at the top sheet of paper stock which is to be fed into the printing press.

[005] Similarly, US Patent document US8064184B2 of Konrad Auf Der Maur (hereinafter“Maur”) discusses another solution for handling static charge build-up on a stack of sheets. However Maur discusses discharging static charges while stacking the sheets not when the sheets are required to be fed for processing. Shown in FIG. 2, Maur provides an ion nozzle 36 that generates an air jet comprising charged particles which is incident on an open side edge of sheets. As a result of this, the sheets are bulged and, at the same time, discharge electrostatic charge from the open side edge.

[006] As the printing and sheet technology is evolving the problem of static charge build-up is becoming more and more aggressive. The above and other methods for handling electro static charge are not enough for new printing and sheet technologies. A solution to the above and other problem is therefore desirable.

SUMMARY OF THE SUBJECT MATTER

[007] The present subject matter provides a feeder and method thereof. The subject matter also relates to an improved guide and method of making thereof. The subject matter also provides a method of manufacturing the feeder and a processor to control the feeder. The present subject matter also provides a sheet processing machine having the feeder. The subject matter also provides a method of manufacturing the machine. It must be noted that the following discussion and terminologies are intended only for illustration and the singular forms "a", "an", and "the" include plural references unless the context clearly expressly dictates otherwise.

[008] According to a first aspect, the present subject matter provides a feeder.

The feeder comprises, a table (101) having a table surface (105) configured to receive a stack of sheets, wherein the stack of sheets includes a plurality of sheets; and a plurality of guides (103a - 103c) removably mounted on the table (101), wherein the plurality of guides (103a - 103c) and the table (101) are adapted for lateral movement of the plurality of guides (103a - 103c) relative to a center of the table (101) to align edges of the stack of sheets characterized in that the plurality of guides (103a - 103c) are provided with perforations (119a- 119f), wherein the perforations (119a- 119J) are in substantially vertical direction from the table surface (105) and are adapted to release ionize air substantially parallel to the table surface (105) and between the sheets of the stack of sheets. In one embodiment, the feeder is provided with an elevator (701, 703 , 113) to raise edges of a top sheet of the stack of sheets. In a second embodiment, the elevator (701, 703 , 113) is a vacuum based elevator and comprises suction heads. In a third embodiment, the feeder is provided with a blower head (117) arranged to release ionized air between the top sheet raised by the elevator (701, 703 , 113) and a sheet following the top sheet of the stack of sheets. In a fourth embodiment, the plurality of guides (103a - 103c) are provided with receivers (109a- 109J) to removably receive nozzles (107a - 107f) and the perforations (119a- 119J) are provided in the nozzles (107a- 107f). In a fifth embodiment, the table (101) is provided with glides (llla-llld) to enable lateral movement of the plurality of guides (103a- 103c). In a sixth embodiment, the feeder is provided with a plurality of nozzle lines (115, 603a) to enable release of ionized air through the perforations (119a- 119J) and the blower head (117). In a seventh

embodiment, the perforations (119a- 119J) are separated from each other based on thickness and/or size of the sheets of the stack of sheets and the table (101) is adapted to handle the stack of sheets, having both uniform and varying thickness of sheets. In an eighth embodiment, the feeder is adapted to retrofit in a sheet processing machine.

[009] According to a second aspect, a method for making a feeder is provided. The method comprises configuring a table (101) having a table surface (105) to receive a stack of sheets, wherein the stack of sheets includes a plurality of sheets; and; adapting a plurality of guides (103a - 103c) and the table (101) for lateral movement of the plurality of guides (103a - 103c) relative a center of the table (101) to enable aligning of edges of the stack of sheets; characterized in that providing the plurality of guides (103a - 103c) with perforations (119a - 119f), wherein the perforations (119a- 119J) are in substantially vertical direction from the table surface (105) and are adapted to release ionize air substantially parallel to the table surface (105) and between the plurality of sheets of the stack of sheets. In ninth embodiment, the method includes providing an elevator (701, 703 , 113) to raise edges of a top sheet of the stack of sheets. In a tenth embodiment, providing the elevator (701, 703 , 113) includes providing a vacuum based elevator that comprises suction heads. In an eleventh embodiment, the method includes providing a blower head (117) and arranging the blower head (117) to release ionized air between the top sheet raised by the elevator (701, 703 , 113) and a sheet following the top sheet of the stack of sheets. In an twelfth embodiment, the method includes providing receivers (109a- 109J) with the plurality of guides (103a - 103c ) to removably receive nozzles (107a - 107f) and providing the nozzles (107a - 107f) with the perforations (119a- 119J). In a thirteenth embodiment, configuring the table (101) includes providing glides (llla-llld) to enable lateral movement of the plurality of guides (103a- 103c). In a fourteenth embodiment, the method includes providing a plurality of nozzle lines (115, 603a) to enable release of ionized air through the perforations (119a- 119 f) and the blower head (117). In a fifteenth embodiment, the method includes adapting the perforations (119a- 119 f) to separate them from each other based on thickness and/or size of the sheets of the stack of sheets, and adapting the table (101) to handle the stack of sheets, having both uniform and varying thickness of sheets. In a sixteenth embodiment, the method includes adapting the feeder for retrofitting the feeder and a sheet processing machine.

[0010] According to a third aspect, the subject matter provides a sheet processing machines having a feeder. The feeder of the sheet processing machine comprises all the features that have been discussed with respect to the first aspect above.

[0011] According to a fourth aspect, the subject matter provides a method of making a sheet processing machine having a feeder. The method of making machine includes all the features of the method discussed with respect the second aspect above. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The matter is discussed with reference to the following figures, in that:

[0013] FIG. 1 is an illustration according to the US patent document 5402304A;

[0014] FIG. 2 is an illustration according to the US Patent document

US8064184B2; [0015] FIG. 3a shows static charge on a top sheet of a stack of sheets;

[0016] FIG. 3b shows change in charge distribution on a top sheet of a stack of sheets after subjecting the stack to an static charge removing process according to a prior art; [0017] FIG. 3c shows a sheet pick-up from a stack of sheets having static charge build up;

[0018] FIGJd shows distribution of static charge in a stack of sheet, wherein a residual static charge has remained on the center part of the sheet; and [0019] FIG. 4 to FIG. 8 show the feeder according to embodiments of the present subject matter.

DETAILED DESCRIPTION

[0020] Smith in the above US Patent document 5402304A attempts to address charge build-up on the top sheet of the stack, however suffers from similar problems associated with plane air-blow method discussed previously. Some reasons for failure of this solution are: the solution only provides blowing ionized air stream on the top sheet of the stack of sheets. As the static charge of the top sheet is neutralized, static charge on remaining sheet continues to remain unaddressed. Therefore, the sheet below the top sheet continues to form an electric dipole between the top sheet and subsequent sheet, resulting in non-effective discharge of the static charges. Furthermore, when the air stream is blown from one side of the sheet, often in absence of strong enough blows, instead of discharging all that results in redistribution of charges.

[0021] For example FIG. 3a shows a stack of sheets with static charge. The static charge is depicted by small circles on the top sheet. When this stack of sheets is subjected to the method an anti-static air stream, the distribution of the static charges may changes and edges away from the nozzle blowing air would continue to carry static charge. FIG 3b shows the stack of sheets after the stack has been exposed to an air stream for discharging the static charge. Furthermore when the sheet is fed for processing sliding movement of the sheet on top of one another generates static charge. Accordingly this problem continues to remain unaddressed. In such condition when a sheet is picked up for feeding, often the sheet also picks adjacent sheet(s) as shown in FIG 3c. Even Maur of the US Patent document US8064184B2 does not provide solution to this problem.

[0022] Furthermore, based on type of processing that need to be performed on the sheets, size of the sheets and size of the stack of the sheet may vary. In such case, a nozzle at fixed place may further add to the inefficient discharging of the static charge. Also, it must be understood that the static charge builds-up due to friction of sheets. When a machine processes a sheet, the machine experiences vibrations. These vibrations or micro vibrations may also be felt by the stack of the sheets resulting in rubbing of sheets across the stack. The rubbing of sheets across the stack causes building of static charge. This means, the mere placing the stack in a feeder of the machine may result in building of static charges when the machine operates. None of the above referred solution addresses at least this problem.

[0023] The present subject matter solves above and other problems associated with feeders. The feeder and the method of making the same according to embodiments of the subject matter shall become clear from the subsequent discussion. Further a sheet processing machine having the feeder and the method of making the machine according to embodiments of the subject matter shall also become clear from the following discussion. Also the following discusses a guide and method of making the guide, the same shall also become clear from the following discussion.

[0024] FIG. 4 to FIG. 8 show the feeder according to embodiments of the present subject matter. Features shown in FIG. 4 to FIG. 8 are as follows. Same feature across the FIG. 4 through FIG. 8 are referred by the same reference numeral. In that, a feeder 100, a table 101, a table surface 105, a plurality of guides 103a, 103b and 103c (in short referred to as“guides ( 103a - 103c)”), perforations 119a- 119/ (also referred to as release holes 119a through 119f ), an elevator 701, 703 and 113, in one embodiment the elevator 701, 703 and 113 is suction heads 701, 703 and 113, a blower head 117, receivers 109a-109f, nozzles 107a - 107f, glides 111a through llld, a suction tool 121, a nozzle line 115, a stack of sheets 610, ionized air carrying pipes 603a through 603c, an ionizer 613, a splitter 605, pipes 603, and arrows 801a through 801f.

[0025] FIG. 4 shows an exploded view of the feeder 100 according to an embodiment of the present subject matter. It shall become clear to a person, after reading this specification, that the present subject matter shows some pluralities of the element for example, guides 103a, 103b and 103c, nozzles 107a through 107f, receivers 109a through 109f, glides 111a through llld, and release holes 119a through 119f. However for practicing the present subject matter, singular elements may also be used. Similarly, some of the elements are shown as singular elements, however the subject matter may be practiced using plurality of these elements.

[0026] The present subject matter provides the feeder 100 which comprises the table 101 and the guide 103. The table 101 has the table surface 105. The guides 103a, 103b and 103c are disposed substantially perpendicular to the table surface 105 of the table 101. The table 101 is designed to receive a plurality of sheets that forms a stack of the sheets. The guides 103a, 103b and 103c are used for aligning the stack of sheets. The guides 103a, 103b and 103c are configured to snug fit the stack so that the sheets of the stack may be fed for processing. The guides 103a, 103b and 103c may enable snug fitting of sheets, by adjusting the position of the guides 103a, 103b and 103c on the table 101. It should be clear to a person that one or more of the guides 103a, 103b and 103c may be stationary, while only one of the guides 103a, 103b and 103c may adjust the position. In the shown example the guides 103a, 103b and 103c are shown as elongated bars, however it must be clear, that in some cases the guides 103a, 103b and 103c may be of shape different than the elongated bars. For instant, a guide of the guides 103a, 103b and 103c may be of L-shape and snug fits comer of the stack. In one example the guides 103a,

103b are provided with the glides 111a through 11 Id. The guides 103a and 103b may glide across the glides 111a through llld. The snug fitting of the sheets is such that it does not hinder feeding of sheets for processing. The guides 103a, 103b and 103c are disposed on the table 101 and are configured to adjust its location on the table 101 by gliding through the glides 111a through llld. The stack of sheets is disposed along the guides 103a, 103b and 103c and the stack grows in a direction substantially perpendicular to the table surface 105 of the table 101 if more sheets to the stack are added.

[0027] According to one aspect the present subject matter provides an improved guide 103a, 103b and 103c. The guides 103a, 103b and 103c according to subject matter are provided with the nozzles 107a through 107f. The nozzles 107a through 107 f are disposed inside of the guides 103a, 103b and 103c. The nozzle 107a through 107f is disposed in the receiver 109a through 109f that are drilled into the guides 103a, 103b and 103c. The nozzles 107a through 107f are disposed in the guides 103a, 103b and 103c such that the nozzles 107a through 107 f do not impede operation of the guides 103a, 103b and 103c. According to another aspect, each of the nozzles 107a through 707/ ^' com prise release holes 119a through 119f. It shall however become clear to a person that in the FIG. 4 only release holes 119d corresponding to the nozzle 107d and receiver 109d are visible. The nozzles 107a through 107f are configured to release stream of ionized air through the release holes 119d. In some aspect, the distance between two adjacent release holes 119a through 119/ are substantially equal to the thickness of the thinnest sheet that the feeder 100 is configured to handle. The release holes 119a through 119/ are placed on the nozzle 107a through 107 f in such a manner that any stream of ionized air encounters the stack of sheets and introduces the ionize air between the sheets of the stack of the sheets. Because the static charges are formed between the sheets, introducing the ionized air between the sheets neutralizes the static charge build up between the sheets.

[0028] In some example, where the sheet size is large enough or the static charge affinity of the sheets are relatively higher. Some residue charge may not get neutralized by the stream of ionized air release from the release holes. More so strength of the blow of air stream may not be increased because it has potential to dislocate the sheet and therefore, potentially misfeeding the sheet. The present subject matter provides a solution for this problem.

[0029] In such cases, when some residue charge remains on the sheet even after blowing the ionized air through the release holes 119a through 119/ the residue charge often concentrates in the center of the sheet as shown in FIG. 3d. The present subject matter provides solution for addressing the residual static charge. The present subject matter provides an improved suction tool 121 and/or elevators 701, 703, 113. The suction tool 121 and/or elevators 701, 703, 113 are configured to pick top sheet of the stack of the sheet. The suction tool 121 and/or elevators 701, 703, 113 comprise the suction head 113, nozzle line 115 and the blower head 117. The nozzle line 115 couples the suction head 113 and the blow head 117. The suction tool 121 and/or elevators 701, 703, 113 is configured to release an ionized air stream, between the top sheet and the sheet immediately following the top sheet. In some example, there may be more than one section tools 121 and/or elevators 701, 703, 113 disposed to pick different edges of the sheets. When the edges of the top sheet are picked up by the suction tool 121 a gap between the top sheet and the following sheet is created. The suction tool 121 may then blow the ionized air stream using the blow head 117 in the gap. The blower head 117 has release holes (not seen). In some cases, the suction tools 121 expose the gap and the release holes 119a through 119f of the nozzles 107a through 107f blow the ionized air through the gap. Thereby neutralizing the remaining residual charge. Now because, the sheet has already been picked up by the suction tools 121 it may directly be fed for processing. A sheet such fed is assured that no static charge is present on the sheet when the sheet is fed for the processing. In some cases, additional brushes may be providing with the sheet processing machine, which is coupled to the feed of the present subject matter.

[0030] FIG. 5 shows an illustrative diagram in which the exploded view of the FIG. 4 has been imploded and the suction tool 121 has been removed, further the glides 111a through llld have been shown to accompany another set of corresponding glides llle through 11 If. The glides llle through 11 If may be used for gliding the guides 103a and 103b and the glides 111a through llld may be used for allowing the nozzles 107a, 107b, 107c and 107f to receive the stream of ionized air. All other elements shown have the same reference numeral and function as discussed with reference to FIG. 4. For the sake of brevity all other reference numerals have not been referred.

[0031] FIG.6 shows a more detailed diagram of the feeder 100 according to an embodiment of the subject matter. The additional elements shown in the FIG. 6 are the stack of sheets 610. Ionized air carrying pipes 603a through 603c, the ionizer 613 and the splitter 605. The splitter 605 receives ionized air and directs it to different direction towards the nozzles 107a through 107 f and to the blower head 117 through the pipe 603. Remaining operation and construction of the feeder 100 remains similar to that has been discussed with reference to FIG. 4.

[0032] FIG. 7 shows the feeder 100 in more details in that it shows, additional suction heads 701 and 703. Also shows the stack of sheets 601 with static charges depicted by small circle across the top sheet. For the sake of clarity the guides 103a through 103c and some other elements have been removed from the depicted diagram. Function and construction of the feeder 100 remains substantially the same as discussed with reference to FIG. 4.

[0033] FIG. 8 shows the feeder 100 same as shown in FIG. 7 expect for the fact that the illustration of FIG. 8 depicts the suction heads in action. Arrows 801a through 801f show the direction of blow of the ionized air. In the FIG. 8 the top sheet may be seen with residue static charges in the center depicted by dots. This residue charges may be removed by lifting the edges of the top sheet and blowing ionized air between the top sheet and the subsequent sheet. It may be noticed on comparing the items A and B of the FIG. 8, that two complimentary edges of the top sheet has been lifted by the suction heads 701 and 703. The ionized air may be now blown between the top sheet and the subsequent sheet using the blower head 117 and the release holes of the nozzles 107a through 107f.

[0034] The subject matter also provides a method of making the feeder substantially as described with reference to the accompanying drawings. The subject matter also provides a controller to control the feeder, the ionizer and the suction head and suction tools substantially as described in this specification. The subject matter also provides an improved guide 103a - 103c configured to enable handling of static charge build up on a stack of sheets and a method of making the guide 103a - 103c, substantially as described herein. The subject matter also provide a sheet processing machine that includes the feeder and also provides a method of making the sheet processing as discussed herein.

[0035] While the subject matter may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described herein. Alternate embodiments or modifications may be practiced without departing from the spirit of the subject matter. The drawings shown are representative only and may omit or over emphasize some features. Further, the methods disclosed herein may be performed in manner and/or order in which the methods are explained. It should be understood that the subject matter is not intended to be limited to the particular forms disclosed. The subject matter is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the subject matter as described above.