JP2018154458A - Paper feeder and image forming system provided therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper feeder capable of loading and storing a large amount of long continuous sheets.SOLUTION: A paper feeder 5 is provided with: a housing main body part 31a, a storage chamber 33 arranged in the housing main body part 31a; a loading tray 36 liftably arranged in the storage chamber 33, and carries out sheets loaded on the loading tray 36 in a carry-out direction. In the paper feeder 5, a housing extension part 31b arranged in the housing main body part 31a can receive a rear side part of a second size sheet extending in the outside of the storage chamber 33 in the carry-out direction, whose length is longer than that of a first size sheet receivable in the storage chamber 33.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a sheet feeding device that supplies a sheet to an image forming apparatus or the like and an image forming system including the sheet feeding device.

  2. Description of the Related Art Conventionally, a sheet feeding device that supplies a sheet to an image forming unit of an image forming apparatus such as a copying machine or a printer is known. In such a sheet feeding device, the sheets on the stacking tray are fed by a feeding roller, and the fed sheets are separated one by one by a separation unit including a sheet feeding roller and a separation member, and the image forming unit of the image forming apparatus The image forming unit forms an image on the sheet. The paper feeding device includes a type including a paper feeding cassette capable of storing about 100 sheets, and a type including a storage capable of storing a large number of sheets of thousands.

  In some cases, it is required to supply a so-called long sheet, which is longer than a standard size sheet, such as a book cover, a catalog, or a poster, to the image forming apparatus. Since such a long sheet is longer than the length of the standard size, for example, as described in Patent Document 1, it is supplied using a manual feed tray mounted on the image forming apparatus, or in Patent Document 2 or Patent. As described in Document 3, an extension tray that supports a rear end portion (an end portion on the rear side in the carry-out direction) that protrudes from the storage portion is provided in the cassette to cope with a long sheet.

JP 2013-10013 A JP-A-6-64762 JP 2013-103777 A

  However, even in such a sheet feeding device, the maximum stacking capacity is about 10 sheets when a long sheet is supplied using a manual feed tray, and about 100 sheets even when an extension tray of a cassette is provided. Cannot handle the supply of long sheets. Further, in the sheet feeding device as described above corresponding to the long sheet, at least a part of the long sheet is left in an exposed state in the external space. For this reason, if there are not enough long sheets in one process, the long sheets must be replenished. If there are remaining long sheets in one process, the supply to the image forming unit is completed. There is a problem that the long sheet needs to be removed and the manual feed tray and the extension tray of the cassette must be returned to a state where they are not used, and the handling is troublesome.

  Accordingly, an object of the present invention is to provide a paper feeding device capable of stacking and storing a large number of long sheets in order to solve the problems existing in the prior art.

  In view of the above-mentioned object, the present invention includes, as a first aspect, a housing main body, a storage provided in the housing main body, and a stacking tray disposed in the storage so as to be movable up and down. A sheet feeding device that unloads sheets stacked thereon in the unloading direction, and has a second size that extends to the outside of the storage longer than the first size of sheets that can be stored in the storage. Provided is a sheet feeding device in which a casing extension capable of accommodating a rear end portion of a sheet in the carrying-out direction is provided in the casing main body.

  In the paper feeding device, a housing extension is provided in the housing body. Therefore, a second-size sheet that is longer than the first-size sheet that can be stored in the storage is stacked on the stacking tray disposed in the storage, and the rear end in the carry-out direction is outside the storage. The rear end portion of the second size sheet in the carry-out direction can be accommodated in the housing extension.

  In the sheet feeding device, it is preferable that the housing extension is formed so as to have a bottom surface at a position higher than the bottom surface of the housing body. In this case, an opening that allows the second size sheet on the stacking tray to extend to the housing extension is formed in the upper portion of the side portion on the rear end side in the carry-out direction of the storage. More preferably.

  Further, the sheet feeding device configured as described above includes a rear end regulating member that is provided in the storage and regulates the position of the rear end in the carry-out direction of the first size sheet on the stacking tray, It is preferable that the rear end regulating member is provided so as to be rotatable between a standing position where the rear end regulating member stands within the storage case and a fall position where the rear end restriction member falls within the storage case. In this case, it is more preferable that the rear end regulating member is configured to be able to fall into the storage until the upper end is positioned below the bottom surface of the housing extension.

  In addition, it is preferable that the paper feeding device further includes an extension tray disposed in the housing extension and connected to the stacking tray. In this case, it is more preferable that the extension tray is detachably connected to the stacking tray.

  In one embodiment, the sheet feeder includes a first lower limit detector that detects that the stacking tray has reached a lower limit position, and a second lower limit that detects that the extension tray has reached a lower limit position. A detector and a control device that controls the lifting and lowering operation of the stacking tray, wherein the control device is configured to store the first size sheet in the storage in the first size mode; When the lower limit detector detects that the stacking tray has reached the lower limit position, the lowering of the stacking tray is stopped, and the second size mode in which the second size sheet is stored in the storage is described above. When the second lower limit detector detects that the extension tray has reached the lower limit position, control may be performed so as to stop the lowering of the stacking tray.

  Further, it is determined that the first size sheet is stored in the storage when the rear end regulating member is in the standing position, and the storage is performed when the rear end regulating member is in the overturned position. It may be determined that the second size sheet is stored in the storage.

  According to a second aspect of the present invention, there is provided an image forming system including an image forming apparatus that forms an image on a sheet, and the above-described sheet feeding device that supplies the sheet to the image forming apparatus.

  According to the present invention, even if a second size sheet that is longer than the first size sheet that can be accommodated in the storage of the sheet feeding device is stacked on the stacking tray, the housing provided in the housing body is also provided. The rear end portion of the second size sheet in the conveyance direction can be stored in the body extension portion. Accordingly, it is possible to handle a sheet having a second size that is longer than the sheet having the first size, that is, a long sheet, by a sheet feeding device capable of supplying a large amount of sheets. Even when handling a long sheet, the entire long sheet is stored in the housing of the paper feeding device, so that a part of the long sheet is prevented from being left exposed to the external space. it can.

1 is an overall configuration diagram of an image forming system including a sheet feeding device according to an embodiment of the present invention. FIG. 2 is an explanatory diagram illustrating an internal configuration of the sheet feeding device illustrated in FIG. 1. FIG. 2 is an explanatory view of the inside of the paper feeding device shown in FIG. 1 as viewed from above. 2A and 2B are explanatory diagrams of a rear end regulating member of the sheet feeding device illustrated in FIG. 1, in which FIG. 1A illustrates a state of a rear end regulating member when a normal size sheet is stored, and FIG. The state when storing is shown. FIG. 2 is an explanatory diagram illustrating an internal state of the sheet feeding device illustrated in FIG. 1 when a normal size sheet is fed. FIG. 2 is an explanatory diagram illustrating an internal state of the sheet feeding device illustrated in FIG. 1 when a long sheet is fed. 3 is a flowchart illustrating a procedure for stacking sheets on the sheet feeding device illustrated in FIG. 1. 6 is a flowchart illustrating an operation until a standby state is entered after sheets are stacked on a stacking tray. 6 is a flowchart illustrating details of a paper feed process. 10 is a flowchart illustrating details of a sheet feeding operation.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In this specification, “sheet conveyance direction” and “sheet feeding direction” mean the sheet conveyance direction from the sheet feeding device 5 to the image forming apparatus 2, and “sheet width direction” means A direction that intersects the sheet conveyance direction and the sheet feeding direction (in the present embodiment, it is described as a direction perpendicular to the sheet conveyance direction).

  First, the overall configuration of the image forming system 1 will be described with reference to FIG. The image forming system 1 includes an image forming apparatus 2, a document reading device 3, a document feeding device 4, a sheet feeding device 5, and a sheet stacking device 6. The image forming apparatus 2 includes a paper feed cassette 7 (in the illustrated embodiment, two paper feed cassettes 7a and 7b) that can store about 100 sheets. Based on the read image data, an image is formed on a sheet supplied from any one of the sheet feeding cassettes 7a and 7b and the sheet feeding device 5, and the image-formed sheet is accumulated in the sheet accumulating device 6. Store. A document sheet can be fed to the document reading device 3 by the document feeding device 4. Here, the sheets handled in the image forming system 1 include small sheets such as A6, B5, and A4, large sheets such as B4 and A3, long sheets other than the standard size, OHP sheets, and tracing. Special sheets such as paper and coated paper are included.

  The image forming apparatus 2 is, for example, a copying machine, a printer, a facsimile, or the like, and is installed on the floor surface. The image forming apparatus 2 only needs to be able to form an image on a sheet, and various image forming mechanisms can be employed. In the illustrated embodiment, an electrostatic image forming mechanism is employed as the image forming mechanism. However, the image forming mechanism of the image forming apparatus 2 is not limited to the electrostatic image forming mechanism, and an ink jet image forming mechanism, an offset image forming mechanism, or the like can also be adopted.

  The image forming apparatus 2 shown in FIG. 1 includes a projector (laser head or the like) 8, a photosensitive drum 9, a developing device 10, a transfer charger 11, and a fixing roller 12. An electrostatic latent image (still image) is formed on the surface of the photosensitive drum 9 by the projector 8, toner is attached to the electrostatic latent image by the developing device 10, and the toner attached on the photosensitive drum 9 is fed into the paper feed cassette. The image is transferred by the transfer charger 11 to the sheet supplied from 7a, 7b or the sheet feeding device 5. The sheet onto which the toner has been transferred is sent to the fixing roller 12 disposed on the downstream side, and after the toner on the sheet is heated and fixed, the sheet is discharged to the sheet stacking device 6 by the discharge roller pair 13.

  Each of the paper feed cassettes 7a and 7b includes a feed roller 14 that feeds the sheet in contact with the uppermost surface of the stored sheet, and a separation roller pair 15 that feeds the fed sheet separately. Is provided. The sheets fed from the paper feed cassettes 7 a and 7 b by the feed roller 14 and separated one by one by the separation roller pair 15 are transported by the transport roller pair 16 and sent to the transfer charger 11 along the transport path 17. . Further, the sheet fed from the sheet feeding device 5 is carried into the conveyance path 17 by the carry-in roller pair 16 a and is similarly sent to the transfer charger 11 along the conveyance path 17 by the conveyance roller pair 16.

  A manual feed tray 18 is provided on the side of the image forming apparatus 2. Normally, the manual feed tray 18 is disposed in a closed state along the side of the image forming apparatus 2. However, when manual feeding is performed, the manual feed tray 18 is disposed in an open state from the side of the image forming apparatus 2. A sheet placed on the tray 18 can be carried into the conveyance path 17.

  A first platen 19 and a second platen 20 made of transparent glass are juxtaposed in the horizontal direction above the document reading device 3. The first platen 19 is used for reading a document set manually, and is formed in a size that allows a maximum-size document to be placed thereon. The second platen 20 is used for reading a document fed from the document feeding device 4 and moving at a predetermined speed.

  Inside the document reading device 3, there are provided first and second reading carriages 21 and 22, photoelectric conversion means having a condenser lens 23 and a photoelectric conversion element 24. The first reading carriage 21 and the second reading carriage 22 are driven by a carriage motor (not shown) to reciprocate below the first platen 19 in the sub-scanning direction. The first reading carriage 21 is provided with a lamp that irradiates light toward the original and a mirror that reflects the light reflected from the original. The second reading carriage 22 has a first reading carriage. Two mirrors for guiding the light from the mirror of the carriage 21 to the condenser lens 23 and the photoelectric conversion element 24 are provided. When reading the original on the first platen 19, the first reading carriage 21 and the second reading carriage 22 are moved and placed on the first platen 19 from the first reading carriage 21. By irradiating the image of the original with light, the reflected light from the original is guided to the photoelectric conversion element 24 via the first reading carriage 21 and the second reading carriage 22 and converted into an electrical signal, thereby converting the original from the original. Generate image data.

  The image forming apparatus 2 includes a control panel 25, an image data storage unit 26, and a buffer memory 27. The control panel 25 is used to control, for example, sheet size, color printing / monochrome printing, and the number of print copies. The image forming conditions such as single-sided printing / double-sided printing and enlarged / reduced printing can be set. The image data storage unit 26 stores image data read by the document reading device 3 and converted by the photoelectric conversion element 24 as described above. The image data storage unit 26 can also store image data transferred through a network, for example. The image data stored in the image data storage unit 26 is transferred to the buffer memory 27 and is sequentially transmitted from the buffer memory 27 to the projector 8.

  The document feeder 4 includes a paper feed tray 28, a sheet transport mechanism 29, and a paper discharge tray 30, and transports the documents placed on the paper feed tray 28 one by one by the sheet transport mechanism 29. Then, it passes over the second platen 20 and is discharged to the paper discharge tray 30. When reading a document fed from the document feeder 4 and passing over the second platen 20, the first reading carriage 21 and the second reading carriage 22 are stopped in advance below the second platen 20. In addition, image data is generated from a document passing over the second platen 20.

  Next, the structure of the paper feeding device 5 will be described in detail with reference to FIGS.

  The paper feeding device 5 includes a housing 31 including a housing main body 31 a disposed on the image forming apparatus 2 side and a housing extension 31 b extending from the upper portion of the housing main body 31 a in a direction away from the image forming apparatus 2. A storage 33 supported in the casing main body 31a so as to be able to be pulled out in a direction orthogonal to a paper feeding direction (a direction in which a sheet is fed from the paper feeding device 5 to the image forming apparatus 2) by a drawer mechanism 32; 33 includes a separation sheet feeding mechanism 34 that separates the sheets in the sheet 33 and supplies the sheets to the image forming apparatus 2 and a control unit 35 that controls the sheet feeding apparatus 5. A stacking tray 36 that can be raised and lowered in the direction is provided. A frame body 37 that supports the housing extension 31b is provided below the housing extension 31b. The stacking tray 36 is a plate-like plate, and the entire first size sheet (hereinafter referred to as “normal size sheet”) can be stacked on the stacking tray 36. In addition, a stacking tray lower limit detector 38 that detects that the stacking tray 36 has reached the lower limit position of the maximum lifting range is provided at the bottom of the storage 33. The stacking tray lower limit detector 38 detects the stacking tray 36. When detected, the lowering of the stacking tray 36 is stopped. On the other hand, an upper surface detector 39 for detecting the uppermost surface of the sheets stacked on the stacking tray 36 is provided at the upper part of the storage 33, and the stacking tray 36 is moved by the lifting mechanism 40 according to the amount of sheets. It is designed to move.

  The housing extension 31b extending from the upper portion of the housing main body 31a in the direction away from the image forming apparatus 2 is positioned such that the upper surface (stacking surface) of the stacking tray 36 is higher than the bottom surface of the housing extension 31b. Sometimes, the rear end portion of the sheet in the sheet feeding direction protruding from the stacking tray 36 can be stored. As a result, the sheet feeding device 5 stores a second size sheet (hereinafter referred to as “long sheet”) that is larger than the normal size sheet and protrudes from the stacking tray 36, and is stored in the image forming apparatus 2. It can be supplied.

  In the illustrated embodiment, the lifting mechanism 40 corresponds to a plurality of wires (only one wire is shown in a simplified manner in FIG. 2) fixed to the support portion of the stacking tray 36. A winding pulley that winds the wire, an intermediate pulley that winds a wire extending between the winding pulley and the corresponding support portion, and a lifting motor M1 that rotationally drives the winding pulley are configured. However, the raising / lowering mechanism 40 is not particularly limited as long as it can raise and lower the stacking tray 36 while maintaining a substantially horizontal state.

  The storage 33 has a substantially box shape with an opening at the top, and when being pulled out from the housing 31, the sheet is loaded onto the stacking tray 36 in the storage 33 through the opening. , Can be loaded. Further, a notch 33a is provided at the upper part of the side wall of the storage 33 on the housing extension 31b side, and a space for storing the stacking tray 36 inside the storage 33 (hereinafter referred to as “loading tray storage space”). Is communicated with the housing extension 31b. The notch 33a is sized to allow the long sheet to protrude from the storage 33 and extend into the housing extension 31b.

  In the stacking tray accommodation space, side end regulating members 41a and 41b positioned with the sheets on the stacking tray 36 sandwiched in the width direction (direction perpendicular to the sheet feeding direction), and the back of the normal size sheet on the stacking tray 36 And a trailing edge regulating member 42 located on the edge (the edge on the side farther from the image forming apparatus 2 in the paper feeding direction) is further provided, and the positions of both side edges in the width direction of the sheets on the stacking tray 36 are on the side. It is regulated by the edge regulating members 41 a and 41 b, and the position of the trailing edge in the sheet feeding direction of the normal size sheet on the stacking tray 36 is regulated by the trailing edge regulating member 42. In the illustrated embodiment, the side end regulating members 41a and 412b are erected on the bottom of the storage 33 so as to be slidable in the width direction of the sheet, for example, by a rack and a pinion, and move in the width direction of the sheet. The rear end regulating member 42 is erected on the bottom of the storage case 33 so as to be slidable in the paper feeding direction, and extends through the windows 36a and 36b provided in the stacking tray 36. It extends through a window 36c provided in the stacking tray 36 so as to allow movement in the paper direction. With such a configuration, the side edge regulating members 41a and 41b and the rear edge regulating member 42 are moved on the bottom of the storage case 33, and the side edge position and the sheet feeding direction of the sheet on the stacking tray 36 according to the sheet size. The rear end position can be regulated.

  Further, as shown in detail in FIG. 4, the rear end regulating member 42 can be rotated downstream in the sheet feeding direction (that is, the stacking tray accommodating space side) with a fulcrum provided at the lower part as an axis. It is configured. Thereby, it is possible to prevent the trailing edge regulating member 42 from hindering the stacking when long sheets are stacked on the stacking tray 36. In the illustrated embodiment, the housing extension 31b is provided only on the top of the housing main body 31a, and when storing a long sheet, the stacking tray 36 is higher than the bottom surface of the housing extension 31b. Must be in position. Therefore, when the rear end regulating member 42 is turned to the side of the stacking tray accommodating space and falls down, the upright position shown in FIG. 4A is present if it is below the bottom surface of the housing extension 31b. Therefore, even if the sheet is rotated by 90 ° and is not completely overturned, it does not hinder the stacking of long sheets on the stacking tray 36. For this reason, in the illustrated embodiment, when dealing with a long sheet, it is rotated by 60 ° from the standing position as shown in FIG. 4A and shown in FIG. A position where the upper end of the trailing end regulating member 42 that is overturned is lower than the lower limit position of the stacking tray 36 when the long sheets are stacked and close to the lower limit position. The rear end regulating member 42 can be easily erected and overturned by minimizing the amount of movement of the rear end regulating member 42 to correspond to the long sheet.

  Note that the window 36c of the stacking tray 36 is large enough to allow the trailing edge regulating member 42 to be rotated from the standing position to the falling position and from the falling position to the standing position when the stacking tray 36 is at any height position. Is formed.

  In the illustrated embodiment, the mode switching detection mechanism 43 further detects the rotational position of the trailing edge regulating member 42, and the control unit 35 stores the normal sheet in the sheet feeding device 5. The sheet feeding device 5 is switched to a long sheet mode for storing a long sheet. For example, as shown in FIG. 4, the mode switching detection mechanism 43 that detects the rotational position of the rear end regulating member 42 includes a detection flag 43 a attached to the rear end regulating member 42 and the bottom plate of the storage 33. A base member 43b that is slidable on the top and supports the rear end regulating member 42 so as to be rotatable, and a mode switching detector 43c provided on the base member 43b. The rear end regulating member 42 rotates to the upright position. The mode switching detector 43c may be disposed at a position where the detection flag 43a is detected when the detection flag 43a is moved and the flag 43a cannot be detected when the detection flag 43a is rotated to the fall position. Of course, the switching between the normal sheet mode and the long sheet mode may be detected by another mechanism, for example, by the operation button 44a provided on the exterior surface of the sheet feeding device 5 or the like. The control panel 25 may be used.

  The separation paper feeding mechanism 34 is in contact with the uppermost surface of the sheets stacked on the stacking tray 36 and feeds the sheets 45 and separates the fed sheets one by one and conveys them to the image forming apparatus 2. Separating and conveying means. The separating / conveying means includes a sheet feeding roller 46 and a separating roller 47 that presses against the sheet feeding roller 46 and prevents the second and subsequent sheets from being supplied.

  The paper feed roller 46 is driven by a paper feed motor M2 via a plurality of gears and timing belts (not shown), and rotates by the drive of the paper feed motor M2 to supply sheets. The feeding roller 45 is rotatably supported by a bracket 48 that is rotatably supported around the shaft of the paper feed roller 46, and the rotation of the shaft of the paper feed roller 46 by the paper feed motor M2 is a plurality of gears. Is transmitted to the feeding roller 45 through the shaft and rotated. Further, the feeding roller 45 can be moved around the shaft of the paper feed roller 46 between an operation position that contacts the upper surface of the sheet and a standby position that is separated from the upper surface of the sheet. In this embodiment, the operation of the solenoid 49 is switched between operation and stop so that the bracket 48 is rotated around the shaft of the paper feed roller 46 to move the feeding roller 45 between the operation position and the standby position.

  The separation roller 47 has a torque limiter (not shown) attached to its rotating shaft. As a result, when two or more sheets are overlapped and nipped at the pressure contact portion between the sheet feeding roller 46 and the separation roller 47, the separation roller 47 stops and the supply of the second and subsequent sheets from the top is prevented. It has become. That is, when a plurality of sheets overlap and enter the nip portion between the paper feed roller 46 and the separation roller 47, the driving force of the paper feed roller 46 is transmitted to the uppermost sheet, while the rotation of the separation roller 47 is stopped. Then, slip occurs between the uppermost sheet and the second and subsequent sheets from above, and the uppermost sheet and the second and subsequent sheets from the top are separated. Of course, other members such as a separation pad may be used instead of the separation roller 47.

  An extension tray 50 that supports a rear end portion of the long sheet protruding from the stacking tray 36 in the sheet feeding direction is disposed in the housing extension 31 b, and the long sheet is stored in the sheet feeding device 5. At this time, the extension tray 50 is connected to the stacking tray 36. As a result, the extension tray 50 can be moved up and down integrally with the stacking tray 36. In the present embodiment, a plurality of female screw holes are provided in the upstream side surface (the right side surface in FIG. 3) of the stacking tray 36 in the sheet feeding direction, and a plurality of penetrations extending through the extension tray 50 in the sheet feeding direction. A connecting shaft 51 having a hole provided at a position corresponding to the female screw hole and having a male screw portion formed at the tip is inserted into the through hole of each extension tray 50, and the male screw portion at the tip of the connecting shaft is inserted into the stacking tray. The stacking tray 36 and the extension tray 50 are connected to each other by being screwed into a female screw hole provided on the side surface 36.

  Note that the outer wall portion on the front side (front side in FIG. 2) of the housing extension 31 b is formed integrally with the front-side exterior portion of the storage 33, and the housing is pulled out as the storage 33 is pulled out. It is comprised so that it may separate from the extension part 31b. Therefore, even when the extension tray 50 is connected to the stacking tray 36, the extension tray 50 can be pulled out from the housing extension 31 b as the storage 33 is pulled out.

  In the housing extension 31b, long sheet side end regulating members 52a and 52b for regulating the positions of both side ends in the sheet width direction of the rear end portion of the long sheet in the sheet feeding direction, and the feeding of the long sheet A long sheet rear end regulating member 53 for regulating the position of the rear end of the direction is provided on the extension tray 50. In the illustrated embodiment, the long sheet side end regulating members 52a and 52b are linked to each other by, for example, a rack and a pinion so as to be slidable in the width direction of the long sheet and slidable in the width direction of the long sheet 50. The long sheet trailing edge regulating member 53 is mounted on the extension tray 50 so as to be slidable in the sheet feeding direction of the long sheet.

  In addition, an extension tray lower limit detector 54 that detects that the extension tray 50 that moves up and down together with the stacking tray 36 has reached the lowest position in the casing extension 31b is provided at the lowermost part of the casing extension 31b. When the extension tray lower limit detector 54 detects the extension tray 50, the controller 35 stops the lowering of the stacking tray 26. Further, when the extension tray lower limit detector 54 detects the extension tray 50 when storing the normal size sheet that can be stored in the storage 33 in the sheet feeding device 5, it recognizes that the extension tray 50 has been forgotten to be removed from the stacking tray 36. Can also be notified.

  The control device 35 includes a sheet information acquisition unit 35a, a stacking tray control unit 35b, a height position setting unit 35c, a lower limit position setting unit 35d, a paper feed control unit 35e, and a detection selection unit 35f. . The sheet information acquisition unit 35a acquires information on the size of the sheets stacked on the stacking tray 36, the stacking tray control unit 35b controls the raising / lowering operation of the stacking tray 36, and the sheet feeding control unit 35e is a separation sheet feeding mechanism. 34 is controlled. Further, the height position setting unit 35c is configured to stop the stacking tray when the sheets are newly stacked on the stacking tray 36 based on the sheet size acquired by the sheet information acquiring unit 35a (hereinafter, referred to as a height position). The lower limit position setting unit 35d sets the lower limit position of the raising / lowering range of the stacking tray 36 based on the sheet size acquired by the sheet information acquisition unit 35a. A normal sheet setting position that is a stacking preparation position in the case of a normal size sheet is defined between the bottom surface of the casing main body 31a and the bottom surface of the casing extension 31b, and is a stacking preparation position in the case of a long sheet. The length sheet set position is defined at a position higher than the bottom surface of the housing extension 31b.

  In the stacking tray control unit 35b, for example, the storage case 33 is placed in the casing 31 in a state in which no sheet is detected by the sheet detector 56 provided on the stacking tray 36 (that is, no sheet is stacked on the stacking tray 36). Set by the height position setting unit 35c when a sheet is newly stacked on the stacking tray 36, such as when it is stored inside or when the storage box 33 is pulled out from the housing 31 for sheet replenishment. The loading tray 36 is moved to the loading preparation position. In addition, when the stacking tray 36 reaches the lower limit position set by the lower limit position setting unit 35d when the stacking tray 36 is lowered, the stacking tray control unit 35 stops the lowering of the stacking tray 36.

  In the sheet feeding device 5 of the illustrated embodiment, the sheet information acquisition unit 35a of the control device 35 stacks on the stacking tray 36 by detecting the switching of the normal sheet mode or the long sheet mode by the mode switching detection mechanism 43. Information on whether the sheet to be processed is a normal size sheet or a long sheet is obtained. However, the sheet information acquisition unit 35a may acquire information regarding whether sheets stacked on the stacking tray 36 are normal size sheets or long sheets from the operation buttons 44a or the control panel 25 of the image forming apparatus 2.

  In the sheet feeder 5 of the illustrated embodiment, in the normal sheet mode, the detection selection unit 35f selects the stacking tray lower limit detector 38, and the lower limit position setting unit 35d performs the stacking tray lower limit detector 38. Is set as the lower limit position, and the height position setting unit 35c sets the lower limit position of the stacking tray 36 detected by the stacking tray lower limit detector 38 as the normal sheet setting position. It has become. As a result, the stacking tray control unit 35b has an upper limit position (a position where the stacking tray 36 is lifted by a predetermined amount from the height position at which the sheet on the stacking tray 36 is detected by the upper surface detector 39) when a normal size sheet is used. And the stacking tray 36 is moved up and down between the lower limit position detected by the stacking tray lower limit detector 38. Further, the stacking tray control unit 35 b moves the stacking tray 36 to a lower limit position detected by the stacking tray lower limit detector 38 when a new normal size sheet is replenished and stacked on the stacking tray 36. On the other hand, in the long sheet mode, the detection selection unit 35f selects the extension tray lower limit detector 54, and the lower limit position setting unit 35d sets the position of the extension tray 50 detected by the extension tray lower limit detector 54 to the lower limit position. The height position setting unit 35c sets the position of the stacking tray 36 when the extension tray 50 is detected by the extension tray lower limit detector 54 as the long sheet setting position. Accordingly, the stacking tray control unit 35b, when a long sheet, has an upper limit position (a position where the stacking tray 36 is raised by a predetermined amount from the height position at which the sheet on the stacking tray 36 is detected by the upper surface detector 39). The stacking tray 36 and the extension tray 50 are moved up and down between the lower limit position detected by the extension tray lower limit detector 54. The stacking tray 35 control unit b moves the stacking tray 36 and the extension tray 50 to the lower limit position detected by the extension tray lower limit detector 54 when a long sheet is newly replenished and stacked on the stacking tray 36.

  In the sheet feeding device 5 configured as described above, in the normal sheet mode in which a normal size sheet is fed, the connection between the stacking tray 36 and the extension tray 50 is released as shown in FIG. A normal size sheet is stacked on the stacking tray 36 in the storage 33 with the rear end regulating member 42 in an upright state, and is raised until the uppermost normal size sheet reaches a predetermined height, so that the separation paper feeding mechanism Then, the sheet is fed to the image forming apparatus 2. On the other hand, in the long sheet mode for feeding a long sheet, as shown in FIG. 6, the stacking tray 36 is raised above the bottom surface of the housing extension 31b, and the trailing edge regulating member 42 is By rotating the trailing edge regulating member 42 to the overturned position so as not to interfere with the stacking of the long sheets, the leading edge of the trailing edge regulating member 42 is positioned below the stacking tray 36, and the extension tray is placed on the stacking tray 36. After connecting 50, long sheets are stacked on the stacking tray 36. At this time, the rear end portion in the sheet feeding direction of the sheet protruding from the stacking tray 36 and extending from the storage 33 is extended by the extension tray 50 connected to the side portion of the stacking tray 36 far from the image forming apparatus 2. The extension tray 50 that is supported and connected to the stacking tray 36 as the stacking tray 36 rises also rises, so that the uppermost long sheet is raised to a predetermined height while maintaining a substantially horizontal state, and separated and fed. The paper is fed to the image forming apparatus 2 by the paper mechanism 34.

  As described above, the sheet feeding device 5 feeds not only a normal size sheet but also a long sheet of a size protruding from the stacking tray 36 in a state in which a large number of sheets are accommodated in the housing 31 without being exposed to the external environment. can do. Further, since the extension tray 50 is connected to the stacking tray 36, the extension tray 50 can be lifted and lowered by the lifting mechanism 40 of the stacking tray 36, and it is necessary to provide a separate lifting mechanism for lifting and lowering the extension tray 50. And the mechanism can be simplified.

  Further, since long sheets are larger and heavier than normal size sheets, the same number of long sheets as normal size sheets are stacked on the stacking tray 36, compared to the case where only normal size sheets are supported. Therefore, a higher output is required for the lifting motor M1 of the lifting mechanism 40. However, in the illustrated embodiment, the housing extension 31b is provided so that the bottom surface thereof is located above the bottom surface of the housing body 31a. Requires that the stacking tray 36 be moved above the bottom surface of the casing extension 31b positioned above the bottom surface of the casing main body 31a, and the stacking tray control unit 35b is also moved to the bottom surface of the casing main body 31a. The stacking tray 36 is moved to a stacking preparation position above the bottom surface of the casing extension 31b positioned above the position. As a result, the amount of long sheets that can be stacked on the stacking tray 36 and the extension tray 50 is smaller than that of a normal size sheet, so that the maximum stacking weight of the stacked long sheets can be reduced, and the normal size It is possible to handle a long sheet by using the lifting motor M1 having the same output as when only the sheet is handled.

  Next, with reference to FIG. 7, a procedure for changing the sheet type stored in the sheet feeding device 5 of the present embodiment will be described.

  When the operator presses a release button 44b for releasing the lock of the storage case 33 provided on the upper surface of the sheet feeding device 5, the stacking tray 36 is lowered and the lock is released, and the storage case 33 can be pulled out from the housing 31. It becomes a state. In the illustrated embodiment, when the storage 33 is pulled out, in the normal sheet mode, the stacking tray 36 is moved to the normal sheet setting position (that is, the lower limit position detected by the stacking tray lower limit detector 38). In the long sheet mode, the stacking tray 36 is moved to the long sheet setting position (that is, the lower limit position where the extension tray 50 is detected by the extension tray lower limit detector 54). When the lock is released, the storage case 33 is pulled out from the casing 31 of the paper feeding device 5 to the front side (front side in FIG. 2) (step S1), and sheets are placed on the stacking tray 36 in the storage case 33. If it remains, the remaining sheet is removed from the stacking tray 36 (step S2).

  Next, when the sheet type accommodated in the sheet feeding device 5 is changed from the normal size sheet to the long sheet (step S3), the rear side is moved from the standing position to the fall position with the storage case 33 being pulled out from the housing 31. The end regulating member 42 is rotated (step S4), the storage 33 is closed and stored in the casing 31 (step S5). Since the loading tray 36 is provided with the window 36c, the trailing edge regulating member 42 and the loading tray 36 interfere when the trailing edge regulating member 42 falls down regardless of the position of the loading tray 36. There is no.

  When the storage 33 is closed, the rear end regulating member 42 is turned to the overturned position, and the detection flag 43a of the mode switching detection mechanism 43 cannot be detected by the mode switching detector 43c, thereby switching to the long sheet mode. The sheet information acquisition unit 35a recognizes that the stacked sheet is a long sheet, and the sheet detector 56 recognizes that there is no sheet on the stacking tray 36. Thereby, the detection selection unit 35f selects the extension tray lower limit detector 54, and the height position setting unit 35c sets the long sheet set position defined at a position higher than the bottom surface of the housing extension 31b to the stacking preparation position. The lower limit position setting unit 35d sets the height position of the stacking tray 36 when the extension tray lower limit detector 54 detects the extension tray 50 as the lower limit position. As a result, the stacking tray control unit 35b raises the stacking tray 36 to the long sheet setting position (step S6). The raising of the stacking tray 36 from the normal sheet setting position to the long sheet setting position is controlled using the encoder EC shown in FIG. That is, the number of pulses of the encoder EC corresponding to the distance from the normal sheet setting position to the long sheet setting position is set in advance, and when the number of pulses output from the encoder EC reaches the preset number of pulses, The tray controller 35b controls the lifting motor M1 so as to stop the stacking tray 36. When the sheet detector 56 detects that there is a sheet on the stacking tray 36, an error or forgetting to take a sheet is notified in a state where the stacking tray 36 is stopped without being raised. Switching to the long sheet mode may be recognized by selecting the long sheet mode on the control panel 25, or may be recognized by operating the operation button 44a. However, in order to accommodate the long sheet in the casing 31, it is necessary to rotate the rear end regulating member 42 to the overturned position, and in order to confirm that preparations for accommodating the long sheet are ready. However, it is preferable that the mode switching detection mechanism 43 recognizes the switching between the normal sheet mode and the long mode.

  When the stacking tray 36 has been raised to the long sheet setting position, the storage 33 is pulled out from the casing 31 of the sheet feeding device 5 again (step S7), and the extension tray 50 is connected to the stacking tray 36 (step S8). . The stacking tray 36 and the extension tray 50 are connected to each of a plurality of through holes provided in the extension tray 50 with the side surface of the extension tray 50 facing the side surface of the stacking tray 36 on the rear end side in the paper feeding direction. The connecting shaft 51 is inserted, and the male screw portion at the tip of the connecting shaft 51 is screwed into the female screw hole provided on the side surface of the stacking tray 36 on the rear end side in the paper feeding direction. However, the connection between the stacking tray 36 and the extension tray 50 is not limited and can be performed by various methods.

  After connecting the extension tray 50 to the stacking tray 36, a long sheet is stacked on the stacking tray 36 and the extension tray 50 and set at a predetermined position (step S9). When the stacking is completed, the storage 33 is closed again. And housed in the housing 31 (step S10). The long sheets on the stacking tray 36 and the extension tray 50 are moved to predetermined positions by moving the side edge regulating members 41a and 41b, the long sheet side edge regulating members 52a and 52b, and the long sheet trailing edge regulating member 53 to a predetermined position. The both ends of the long sheet are brought into contact with the side end regulating members 41a and 41b and the long sheet side end regulating members 52a and 52b, and the rear end of the long sheet in the sheet feeding direction is brought into contact with the long sheet rear end regulating member 53. By contacting, it is arranged at a predetermined position. The outer wall portion on the front side of the housing extension 31b is pulled away from the housing extension 31b when the storage 33 is pulled out, so that the extension tray 50 extends the housing when the storage 33 is pulled out. There is no interference with the outer wall of the portion 31b. Further, since the leading end of the trailing edge regulating member 42 is rotated to the fall position positioned below the stacking tray 36 at the long sheet setting position, the long sheet protrudes from the stacking tray 36 and is stored in the storage case 33. It does not hinder the projection to the housing extension 31b.

  On the other hand, when the sheet type stored in the sheet feeding device 5 is changed from the long sheet to the normal size sheet (step S3), the male screw at the tip of the connecting shaft 51 in a state where the storage case 33 is pulled out from the housing 31. The connection shaft 51 is pulled out from the through hole of the extension tray 50 and the extension tray 50 is removed from the stacking tray 36 (step S11). When the drawer is pulled out, it is in the long sheet mode, the detection selection unit 35f selects the extension tray lower limit detector 54, and the lower limit position setting unit 35d determines the lower limit position of the stacking tray 36 as the extension tray lower limit detector. Since the extension tray 50 is set at a position where the extension tray 50 is detected by 54, the stacking tray 36 and the extension tray 50 are positioned at least above the bottom surface of the housing extension 31b. In the present embodiment, the position at which the extension tray 50 is detected by the extension tray detector 54 is set as the long sheet setting position (stacking preparation position in the case of long sheets). The stacking tray 36 and the extension tray 50 are lowered by the stacking tray control unit 35b to a position where the extension tray 50 is detected by the extension tray detector 54 when pulled out from the housing 31. Further, since the outer wall portion on the front side of the housing extension portion 31b is pulled away from the housing extension portion 31b along with the drawer of the storage case 33, the extension tray 50 is extended by the case when the storage case 33 is pulled out. There is no interference with the outer wall of the portion 31b. Next, the rear end regulating member 42 is rotated from the fall position to the standing position (step S12), and the storage 33 is closed and accommodated in the housing 31 (step S13). Since the stacking tray 36 is provided with the window 36c, the stacking tray 36 does not interfere with the stacking tray 36 when the trailing end regulating member 42 falls, regardless of the position of the stacking tray 36.

  When the storage case 33 is closed, the rear end regulating member 42 is turned to the upright position, and the detection flag 43a of the mode switching detection mechanism 43 is detected by the mode switching detector 43c, thereby switching to the normal sheet mode. Is detected by the sheet information acquisition unit 35a and the sheet detector 56 recognizes that there is no sheet on the stacking tray 36. As a result, the detection selection unit 35f selects the stacking tray lower limit detector 38, and the height position setting unit 35c sets the normal sheet setting position defined at the bottom of the housing main body 31a as the stacking preparation position. The lower limit position setting unit 35d sets the height position at which the tray 36 is detected by the stacking tray lower limit detector 38 as the lower limit position. As a result, the stacking tray control unit 35b lowers the stacking tray 36 to the normal sheet setting position (step S14). Switching to the normal sheet mode may be recognized by selecting the normal sheet mode on the control panel 25, or may be recognized by operating the operation button 44a. However, the switching between the normal sheet mode and the long mode is performed by the mode switching detection mechanism 43 in order to confirm that the trailing edge regulating member 42 is in the upright position and is ready to receive the normal size sheet. It is preferable to recognize.

  When the lowering of the stacking tray 36 to the normal sheet setting position is completed, the storage 33 is pulled out from the casing 31 of the sheet feeding device 5 again (step S15), and normal size sheets are stacked on the stacking tray 36, and the predetermined position is reached. (Step S16), and when loading is completed, the storage 33 is closed again and stored in the housing 31 (Step S10). For the normal size sheet on the stacking tray 36, the side end regulating members 41a and 41b and the rear end regulating member 42 are moved to predetermined positions, and both side ends of the normal size sheet are brought into contact with the side end regulating members 41a and 41b. The normal size sheet is arranged at a predetermined position by contacting the trailing edge regulating member 42 with the trailing edge of the sheet feeding direction rotated to the standing position.

  When the storage case 33 is pushed into the casing 31 and closed, the stacking tray control unit 35b arranges the uppermost surface of the sheets stacked on the stacking tray 36 at the feeding position as shown in FIG. Then, the stacking tray 36 is raised. Specifically, when the storage 33 is closed and an open / close detector (not shown) is turned on (step S17), the stacking tray control unit 35b drives the lift motor M1 to raise the stacking tray 36 (step S17). S18) When the upper surface of the uppermost sheet on the stacking tray 36 comes into contact with the feeding roller 45 and the upper surface detector 39 detects the upper surface of the uppermost sheet and is turned on (step S19), the upper surface detector 39 is turned on. The stacking tray 36 is raised by a predetermined amount from that position, the lifting motor M1 is stopped, and the stacking tray 36 is stopped (step S20). As a result, the upper surface of the uppermost sheet on the stacking tray 36 is arranged at the feeding position, and preparation for feeding is completed.

  Next, with reference to FIG. 9 and FIG. 10, processing performed at the time of paper feeding will be described.

  After the upper surface of the uppermost sheet on the stacking tray 36 is arranged at the feeding position, when there is no paper feed signal from the image forming apparatus 2 in step S21 and a predetermined time has passed (step S22), the stacking tray control unit 35b Then, the elevating motor M1 is driven, and the stacking tray 36 is lowered by a predetermined amount and stopped to a rest position where the upper surface of the uppermost sheet on the stacking tray 36 is separated from the feeding roller 45 (step S23). In this way, the upper surface of the uppermost sheet on the stacking tray 36 is put on standby at a rest position where the upper surface of the sheet is separated from the feeding roller 45, so that the roller can be placed on the upper surface of the sheet even if the sheet feeding operation is not performed for a long time. It is possible to prevent traces from remaining.

  When a paper feed signal is received from the image forming apparatus 2 while the stacking tray 36 is moved to the rest position (step S24), the stacking tray control unit 35b drives the lift motor M1 to raise the stacking tray 36. (Step S25). The stacking tray 36 is raised, the upper surface of the uppermost sheet on the stacking tray 36 comes into contact with the feeding roller 45, and the upper surface detector 39 is turned on (step S26). The stacking tray control unit 35b raises the stacking tray 36 by a predetermined amount from the time when the upper surface detector 39 is turned on, stops the lifting motor M1, and stops the lifting of the stacking tray 36 (step S27). As a result, the upper surface of the uppermost sheet on the stacking tray 36 is arranged at the feeding position, and the sheet on the stacking tray 36 can be fed by the feeding roller 45, and the sheet feeding operation is performed (step S28).

  On the other hand, when the control unit 35 receives a paper feed signal in step S21 after the upper surface of the uppermost sheet on the stacking tray 36 is arranged at the feeding position and before a predetermined time has elapsed, a paper feed operation described later is executed. (Step S29).

  The above process is repeated until the paper feed process becomes unnecessary (step S30).

  In the sheet feeding operation, the sheet feeding control unit 35e drives the sheet feeding motor M2 in a state where the upper surface of the uppermost sheet on the stacking tray 36 is disposed at the feeding position and is in contact with the feeding roller 45, thereby feeding the feeding roller. 45 and the paper feed roller 46 are rotated. As a result, the uppermost sheet on the stacking tray 36 is fed out by the feeding roller 45, separated into one sheet by the paper feeding roller 46 and the separation roller 47, and fed to the image forming apparatus 2 (step S31). Further, when the leading edge of the fed sheet in the sheet feeding direction is detected and turned ON by the sheet detector 55 (step S32), the sheet feeding control unit 35e detects when the sheet detector 55 is turned on (ie, the sheet detector 55). After the sheet is conveyed by a predetermined amount from the time when the leading edge of the sheet is detected, the solenoid 49 is operated to raise the feeding roller 45 to the feeding roller standby position that is away from the upper surface of the uppermost sheet on the stacking tray 36 (step S33). ). Simultaneously with the raising of the feeding roller 45, the paper feeding motor M2 is stopped to stop the rotation of the feeding roller 45 and the paper feeding roller 46 (step S34).

  When the leading edge of the fed sheet is detected by the sheet detector 55 and then conveyed by a predetermined amount, the leading edge of the fed sheet is nipped by the carry-in roller pair 16a of the image forming apparatus 2. . Therefore, in this state, the sheet is conveyed while being pulled out from the nip portion between the paper feed roller 46 and the separation roller 47 by the carry-in roller pair 16a. As described above, by lifting the feeding roller 45 to the feeding roller standby position in step S33 and separating it from the sheet, it is possible to reduce the drawing load when being carried into the image forming apparatus 2 by the carry-in roller pair 16a. In addition, it is possible to prevent the sheet from being contaminated with dirt and marks by the feeding roller 45 when the sheet is pulled out.

  Further, when the sheet is carried into the image forming apparatus 2 and the sheet detector 55 is turned off, that is, when the rear end of the sheet in the sheet feeding direction passes through the sheet detector 55 (step S35), the sheet feeding control unit 35e is a solenoid. The operation of 49 is stopped, and the feeding roller 45 is lowered (step S36). The paper feeding operation is performed as described above.

  The sheet feeding apparatus and the image forming system including the sheet feeding apparatus according to the present invention have been described above with reference to the illustrated embodiment. However, the present invention is not limited to the illustrated embodiment. For example, in the illustrated embodiment, the housing body 31a and the housing extension 31b are integrally formed in the housing 31, but the housing body 31a and the housing extension 31b are separated. You may make it connect after forming with a body. Further, a control device 35 that controls the operation of the paper feeding device 5 including the raising and lowering of the stacking tray 36 and the operation of the separation paper feeding mechanism 34 is installed either inside or outside the housing 31 of the paper feeding device 5. Also good. For example, in the illustrated embodiment, the control device 35 is provided in the paper feeding device 5, but the control device 35 is provided in another device such as the image forming device 2, and the lifting motor is moved from the image forming device 2 or the like. It is also possible to control driving of an actuator such as M1. Further, the control device 35 may be provided separately from the paper feeding device 5, the image forming device 2, and the like.

DESCRIPTION OF SYMBOLS 1 Image forming system 2 Image forming apparatus 5 Paper feeder 31 Case 31a Case main-body part 31b Case extension part 33 Storage 35 Control part 36 Stack tray 38 Stack tray lower limit detector 42 Rear end regulation member 50 Extension tray 54 Extension Tray lower limit detector

Claims (10)

A sheet feeding device that includes a housing main body, a storage provided in the housing main body, and a stacking tray that can be moved up and down in the storage, and transports sheets stacked on the stacking tray in a transporting direction. Because
A housing extension capable of storing a rear end portion of a second size sheet extending outside the storage longer than the first size sheet that can be stored in the storage; A paper feeding device provided in the casing main body.   The sheet feeding device according to claim 1, wherein the housing extension is formed to have a bottom surface at a position higher than a bottom surface of the housing body.   An opening for allowing the second size sheet on the stacking tray to extend to the housing extension is formed in an upper portion of a side portion on the rear end side in the carry-out direction of the storage. Item 3. The sheet feeding device according to Item 2.   A rear end regulating member that is provided in the storage and regulates the position of the rear end in the carrying-out direction of the first size sheet on the stacking tray, and the rear end regulating member stands up in the storage The sheet feeding device according to any one of claims 1 to 3, wherein the sheet feeding device is provided so as to be rotatable between a standing position to be turned and a fall position to be fallen into the storage.   5. The sheet feeding device according to claim 4, wherein the rear end regulating member is configured to be able to fall down in the storage until an upper end is positioned below a bottom surface of the housing extension.   The sheet feeding device according to claim 1, further comprising an extension tray disposed in the housing extension and coupled to the stacking tray.   The sheet feeding device according to claim 6, wherein the extension tray is detachably connected to the stacking tray.   A first lower limit detector that detects that the stacking tray has reached the lower limit position, a second lower limit detector that detects that the extension tray has reached the lower limit position, and controls the lifting operation of the stacking tray And a controller that controls the stacking tray to a lower limit position by the first lower limit detector in a first size mode in which the first size sheet is stored in the storage. When it is detected that the stacking tray has been lowered, the lowering of the extension tray is stopped by the second lower limit detector in the second size mode in which the second size sheet is stored in the storage. The sheet feeding device according to claim 6 or 7, wherein when the arrival at the position is detected, control is performed so as to stop the lowering of the stacking tray.   When the rear end regulating member is in the upright position, it is determined that the first size sheet is stored in the storage, and when the rear end regulating member is in the overturned position, The sheet feeding device according to claim 4, wherein it is determined that the second size sheet is stored.   An image forming apparatus comprising: an image forming apparatus that forms an image on a sheet; and the sheet feeding device according to claim 1 that supplies the sheet to the image forming apparatus. system.

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