JP5877735B2 - Paper feeding device and image forming apparatus - Google Patents

Description

  The present invention relates to a paper feeding device and an image forming apparatus that draw out and send out paper from a bundle of paper stacked on a paper stacking table.

  This type of paper feeding device includes a paper stacking table on which a stack of sheets is stacked, a paper transporting belt disposed above the paper stacking base, and a fan that sucks air through the vent holes of the paper transporting belt. In some cases, the uppermost sheet of the sheet bundle is attracted to and conveyed by the sheet conveying belt by suction of air through the ventilation holes of the conveying belt.

  Further, in such a paper feeding device, air is blown onto the front end surface of the sheet bundle, air is allowed to enter between the sheets, the sheets are dispersed, and the sheets are sucked one by one from the sheet bundle. It may be easy to pull out and prevent double feeding of paper.

  For example, in Patent Document 1, air is blown onto the front end surface of a sheet bundle, each sheet is dispersed, and the sheets of the sheet bundle are sucked and conveyed one by one on the surface of the sheet conveyance belt. Further, the rear end side of the upper surface of the sheet bundle is pressed by the pressing member and the sheet surface following member to prevent the sheet upper end of the sheet bundle from being lifted, and the upper position of the sheet bundle is prevented from being erroneously detected.

Japanese Patent Application Laid-Open No. 07-206216

  By the way, in a low-humidity environment, the paper in the upper layer of the paper bundle may lose moisture, and the paper may curl. For example, the leading ends of a plurality of sheets in the upper layer of the sheet bundle may curl and warp. In this case, when air is blown onto the leading edge of the stack of paper, the air is received by the back side of the leading edge of each sheet, and the leading edge of each sheet floats up and overlaps, causing the air to flow between the sheets. The paper was attracted to and transported by the paper transport belt while overlapping, and the paper was double fed.

  In Patent Document 1, since the rear end side of the upper surface of the sheet bundle is pressed by the pressing member and the sheet surface following member, the leading end side of each sheet that has been warped cannot be pressed. Further, it is difficult to adsorb the sheet by the sheet conveying belt by simply pressing the leading end side of each sheet.

  Therefore, the present invention has been made in view of the above-described conventional problems, and restricts the curling of the front end side of each sheet without interfering with the sheet suction operation by the sheet transport belt, thereby allowing air to flow to each sheet. It is an object of the present invention to provide a sheet feeding device and an image forming apparatus that can be surely inserted between the two.

In order to solve the above-described problems, the following first to fourth sheet feeding devices are provided.
(1) Paper Feeding Device According to the First Aspect In the paper feeding device according to the first aspect of the present invention, a sheet bundle is loaded on a sheet stacking table, air is sucked through a sheet conveying member, and the sheets of the sheet bundle are collected. A sheet feeding device that sucks and conveys a sheet conveying member, wherein an air blowing unit that blows air onto a leading end of the sheet bundle, and an end portion in a direction orthogonal to the sheet conveying direction on the top surface of the sheet bundle And a sheet regulating member provided on the leading end side of the sheet , and the sheet regulating member is supported so as to be rotatable and movable in a direction in which the sheet regulating member comes in contact with and separates from the upper surface of the sheet bundle .
(2) Paper feeder of the second aspect
The sheet feeding device according to the second aspect of the present invention is configured to load a bundle of sheets on a sheet stacking table, suck air through a sheet conveying member, and suck and convey the sheets of the sheet bundle to the sheet conveying member. An air blowing unit that blows air to a leading end of the sheet bundle; and an end portion in a direction orthogonal to the sheet conveying direction on the upper surface of the sheet bundle and provided on the leading end side of the sheet. A paper regulating member, and the rear end portion of the paper regulating member facing the rear end side of the paper bundle is closer to the center from the side edge of the paper bundle in a direction orthogonal to the paper transport direction. In the transport direction of the paper sheet is inclined so as to approach the front end of the sheet bundle.
(3) Paper feeder of the third aspect
According to a third aspect of the present invention, there is provided a sheet feeding device that stacks a sheet bundle on a sheet stacking table, sucks air through a sheet conveying member, and sucks and conveys the sheets of the sheet bundle to the sheet conveying member. An air blowing unit that blows air to a leading end of the sheet bundle; and an end portion in a direction orthogonal to the sheet conveying direction on the upper surface of the sheet bundle and provided on the leading end side of the sheet. A sheet regulating member, and the sheet regulating member is plate-shaped.
(4) Paper feeder of the fourth aspect
According to a fourth aspect of the present invention, there is provided a sheet feeding device that stacks a sheet bundle on a sheet stacking table, sucks air through a sheet conveying member, and sucks and conveys the sheets of the sheet bundle to the sheet conveying member. An air blowing unit that blows air to a leading end of the sheet bundle; and an end portion in a direction orthogonal to the sheet conveying direction on the upper surface of the sheet bundle and provided on the leading end side of the sheet. The portion of the sheet regulating member facing away from the sheet bundle approaches the upper surface of the sheet bundle as it approaches the center of the sheet bundle in a direction orthogonal to the sheet conveyance direction. So as to be inclined.

In the sheet feeders according to the first to fourth aspects of the present invention, the sheet regulating member is disposed to face the end of the upper surface of the sheet bundle. For this reason, even when a plurality of sheets in the upper layer of the sheet bundle are curled and curled in a low humidity environment, the edge of the sheet abuts against the sheet regulating member, and the curling of the sheet is regulated, and the sheet is generally flat. Maintained. In this state, when air is blown from the air blowing unit to the front end surface of the sheet bundle, the air quickly enters between the sheets, the sheets vary, and the sheet conveying member removes the sheets from the sheet bundle. Each sheet can be adsorbed and pulled out one by one, thereby preventing paper double feeding.
Furthermore, in the paper feeding device according to the first aspect of the present invention, the paper restricting member is supported so as to be able to rotate and move in a direction of coming into contact with and separating from the upper surface of the paper bundle, thereby rotating the paper restricting member. The sheet bundle can be taken in and out of the sheet stacking table while being moved and retracted.
In the paper feeding device according to the second aspect of the present invention, the rear end portion of the paper regulating member facing the rear end side of the paper bundle is centered from the side edge of the paper bundle in a direction perpendicular to the paper transport direction. The closer to the leading end of the bundle of sheets in the sheet transport direction, the wider the space on the rear end side of the sheet regulating member. This can be done easily on the rear end side of the regulating member.
In the paper feeding device according to the third aspect of the present invention, the paper restricting member is plate-shaped, so that the strength of the paper restricting member can be improved.
In the paper feeding device according to the fourth aspect of the present invention, the portion of the paper regulating member that faces away from the paper bundle is closer to the center of the paper bundle in a direction perpendicular to the paper transport direction. By inclining so as to approach the upper surface of the bundle, when the sheet bundle is loaded into or removed from the sheet stacking base, the sheet bundle comes into contact with the inclined portion of the sheet regulating member and quickly pushes the sheet regulating member away. .

Further, in the second to fourth aspects according to the paper feeding device of the present invention, the paper restricting member can be exemplified so as to be rotatable and movable in a direction in which the paper restricting member comes in contact with and separates from the upper surface of the paper bundle. .

In this case, it is possible to perform the operation of loading and unloading the sheet bundle with respect to the sheet stacking table while rotating and retracting the sheet regulating member.

In the paper feeding device according to the first aspect, the third aspect, and the fourth aspect of the present invention, the rear end portion of the paper regulating member facing the rear end side of the paper bundle is orthogonal to the paper transport direction. In the direction, the side of the sheet bundle is inclined so as to approach the front end of the sheet bundle in the sheet conveyance direction as it approaches the center from the side edge of the sheet bundle.

In this case, since the space on the rear end side of the paper restricting member is widened, the loading / unloading operation of the paper with respect to the paper stacking base can be easily performed on the rear end side of the paper restricting member.

Further, in the sheet feeding device according to the first aspect, the second aspect, and the fourth aspect of the present invention, the sheet regulating member can be exemplified as a plate-shaped one.

Thereby, the intensity | strength of a paper control member can be improved.

In the sheet feeding device according to any one of the first to third aspects of the present invention, the portion of the sheet regulating member that faces away from the sheet bundle may be arranged in a direction perpendicular to the sheet conveyance direction. For example, an aspect may be exemplified in which the closer to the center, the closer to the upper surface of the sheet bundle.

In this case, when a paper bundle loading / unloading operation with respect to the paper stacking table is performed, the paper bundle comes into contact with the inclined portion of the paper regulating member and quickly pushes the paper regulating member away.

Further, in the paper feeding device of the present invention, when the paper regulating member is supported so as to be rotatable in a direction in which the paper regulating member comes in contact with and separates from the top surface of the paper bundle, the paper regulating member is placed on the top surface of the paper bundle. And the sheet regulating member rotates and moves in a direction of contacting and separating from the upper surface of the sheet bundle against the urging force of the urging section. An aspect can be illustrated.

In this case, when the paper bundle loading / unloading operation is performed with respect to the paper stacking base, the paper restriction member is pushed away by the paper bundle and rotates, so that the paper restriction member does not interfere with the paper bundle loading / unloading operation. . Further, when the paper is attracted to the paper transport member, the end of the paper comes into contact with the paper regulating member, the paper regulating member rotates slightly, and the thicker the paper or the higher the rigidity of the paper, The rotation angle of the sheet regulating member is increased. For this reason, even if the paper is thick or the rigidity of the paper is high, the edge of the paper is not strongly pressed by the paper regulating member, and the resistance of the paper caused by the sliding contact with the paper regulating member increases. The sheet can be quickly pulled out by the sheet conveying member.

Te Such sheet feeder smell, for example, the sheet regulating member has a respective axis of rotation movable in the direction toward or away from the the paper regulating member with respect to the upper surface of the sheet bundle, the biasing portion Can be exemplified by pulling the axis of the sheet regulating member in a direction perpendicular to the axis and holding the sheet regulating member so as to be parallel to the upper surface of the sheet bundle.

Further, in the paper feeding device of the present invention, when the paper regulating member is supported so as to be rotatable in a direction in which the paper regulating member comes in contact with and separates from the upper surface of the paper bundle, the paper regulating member An example of the rotational movement is possible until the direction is orthogonal to the upper surface.

In this case, when the paper bundle loading / unloading operation is performed with respect to the paper stacking base, the paper regulating member is pushed away by the paper bundle and rotates until it is perpendicular to the upper surface of the paper bundle. The work in and out becomes easy.

Further, in the sheet feeding device according to the first to fourth aspects of the present invention, the sheet regulating member can be exemplified as being spaced apart at both ends in the orthogonal direction on the upper surface of the sheet bundle.

In this case, since both end portions of the paper abut against each paper regulating member, the warping of the paper is well regulated, and the paper is reliably corrected in a flat shape.

In such a sheet feeding device, a position detection unit that detects that the upper surface of the sheet bundle has reached a specified position, and until the position detection unit detects that the upper surface of the sheet bundle has reached a specified position. An ascending drive unit that raises the sheet stacking base, and the sheet regulating member is spaced apart from the end of the upper surface of the sheet bundle that has reached the specified position by a certain distance. The aspect provided in can be illustrated.

Thereby, the separation distance between the sheet regulating member and the upper surface of the sheet bundle is kept constant.

  On the other hand, an image forming apparatus of the present invention includes the paper feeding device of the present invention and a printing unit that prints an image on a sheet supplied from the paper feeding device.

  Such an image forming apparatus of the present invention also has the same operational effects as the sheet feeding apparatus of the present invention.

  In the present invention as described above, the sheet regulating member is disposed to face the end of the upper surface of the sheet bundle. For this reason, even when a plurality of sheets in the upper layer of the sheet bundle are curled and curled in a low humidity environment, the edge of the sheet abuts against the sheet regulating member, and the curling of the sheet is regulated, and the sheet is generally flat. Maintained. In this state, when air is blown from the air blowing unit to the front end surface of the sheet bundle, the air quickly enters between the sheets, the sheets vary, and the sheet conveying member removes the sheets from the sheet bundle. Each sheet can be adsorbed and pulled out one by one, thereby preventing paper double feeding.

1 is a cross-sectional view illustrating an image forming apparatus to which an embodiment of a paper feeding device of the present invention is applied. FIG. 3 is a perspective view illustrating an appearance of the sheet feeding device according to the present embodiment when viewed from obliquely above the front side. It is a top view which shows a paper feeder. It is a front view which shows a paper feeder. FIG. 6 is a perspective view showing the sheet feeding device with the sheet drawer portion removed, as viewed obliquely from the upper rear. (A), (b) is an enlarged perspective view showing the vicinity of the front and rear sheet regulating members in the sheet feeding device as viewed from below. (A), (b) is sectional drawing and a top view which show a paper control member, a frame, etc. roughly. (A), (b) is sectional drawing which shows the state which the sheet | seat control member rotated about 90 degree | times upward, and the state rotated about 90 degree | times downward. It is a perspective view which shows a contact member and a position switching part seeing from the diagonally forward direction, and has shown the state when a paper feeder is pulled out. It is a perspective view which shows a contact member and a position switching part seeing from diagonally forward, and has shown the state when a paper feeder is pushed in. (A), (b), (c) is a side view which shows the positional relationship of the retracting position of a contact member, a standby position, and a suction position, the shielding piece of a contact member, and an optical sensor. FIG. 3 is a perspective view showing a paper drawer portion in the paper feeding device as viewed from the front and obliquely above. It is a perspective view which shows a paper drawer part seeing from back diagonally upward. It is a perspective view which shows a paper drawer part seeing from back diagonally downward. It is sectional drawing which shows a paper feeding apparatus roughly. (A) is a perspective view schematically showing a recording paper suction state in the paper feeding device of the present embodiment, (b) is a perspective view schematically showing a recording paper curled and warped, (c) () Is a perspective view schematically showing the state of the recording paper before suction in the paper feeding device of this embodiment, and (d) is a perspective view showing a state in which only one end of the recording paper curled and curled is restricted. FIG.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a cross-sectional view showing an image forming apparatus to which an embodiment of a paper feeding device of the present invention is applied. The image forming apparatus 1 is roughly composed of a document reading device 2, a printing unit 11, a paper transport unit 12, a paper supply unit 13, and a large-capacity paper feed cassette (LCC) 14.

  In the printing unit 11, after the residual toner on the surface of the photosensitive drum 21 is removed and collected by the cleaning device 26, the surface of the photosensitive drum 21 is uniformly charged to a predetermined potential by the charging device 22, and then the laser exposure device 23. The surface of the photosensitive drum 21 is exposed to form an electrostatic latent image on the surface, and the developing device 24 develops the electrostatic latent image on the surface of the photosensitive drum 21 to form a toner image on the surface of the photosensitive drum 21. To do.

  The transfer roller 25 is pressed against the photosensitive drum 21 to form a nip area with the photosensitive drum 21, and the recording paper conveyed through the paper conveyance path 33 is sandwiched and conveyed in the nip area. At the same time, the toner image on the surface of the photosensitive drum 21 is transferred onto the recording paper. Then, the recording paper is sandwiched between the heating roller 28 and the pressure roller 29 of the fixing device 27 and heated and pressed to fix the toner image on the recording paper.

  On the other hand, the paper supply unit 13 includes a plurality of paper supply cassettes 38. Each paper feed cassette 38 includes a pickup roller 39 and the like for pulling out and feeding out recording sheets one by one, and sends out the pulled-out recording sheets to the sheet transport path 33 of the sheet transport section 12.

  The large-capacity paper feed cassette (LCC) 14 can store a large amount of recording paper, pulls out the recording paper one by one, and sends it out to the paper transport path 33 of the paper transport section 12.

  The recording sheet is conveyed through a sheet conveying path 33 and is discharged to a sheet discharge tray 37 via a transfer roller 25 and a fixing device 27 and a sheet discharge roller 36. In this paper conveyance path 33, the recording paper is temporarily stopped and the leading edges of the recording paper are aligned, and then the recording paper is fed in accordance with the transfer timing of the toner image in the nip area between the photosensitive drum 21 and the transfer roller 25. A registration roller 32 for starting conveyance, a conveyance roller 31 for urging conveyance of a recording sheet, a sheet discharge roller 36, and the like are arranged.

  When printing not only on the front side of the recording paper but also on the back side, the position of the branching claw 35 is switched, and the recording paper is conveyed from the paper discharge roller 36 to the reverse path 34 in the reverse direction. The front and back sides are reversed, and the recording paper is again guided to the registration roller 32, and an image is recorded and fixed on the back surface of the recording paper in the same manner as the front surface of the recording paper, and the recording paper is discharged to the paper discharge tray 37.

  Next, the document reading device 2 mounted on the upper body of the image forming apparatus 1 will be described. In the document reading apparatus 2, the document conveying unit 42 is pivotally supported on the inner side of the first reading unit 41 by a hinge (not shown), and the document conveying unit 42 is moved up and down to move the front portion up and down. 42 can be opened and a document sheet can be placed on the platen glass 44 of the first reading unit 41.

  In the first reading unit 41, the first scanning unit 45 illuminates the original paper surface on the platen glass 44 with the light source 51 while moving in the sub-scanning direction, and reflects the reflected light by the first reflecting mirror 52. Guide to the second scanning unit 46. The second scanning unit 46 reflects the reflected light from the original paper by the second and third reflecting mirrors 53 and 54 while moving following the first scanning unit 45. The reflected light is condensed on a CCD 48 (Charge Coupled Device) by the imaging lens 47, and the image of the original paper is read by the CCD 48.

  Further, when reading the image on the surface of the original sheet conveyed by the original conveying section 42, the first scanning unit 45 is moved to the reading position below the original reading glass 55, and the first scanning unit 45 is moved in accordance with the position of the first scanning unit 45. The two scanning unit 46 is positioned. In this state, the original paper on the original tray 57 is pulled out by the pickup roller 56, the original paper is conveyed through the original conveyance path 58, and the surface of the original paper is passed through the original reading glass 55 by the light source 51 of the first scanning unit 45. Illuminated, the reflected light from the original paper is guided to the imaging lens 47 by the respective reflection mirrors of the first and second scanning units 45 and 46, the image of the original paper is read by the CCD 48, and the original paper is discharged to the original paper discharge roller 61. To the document discharge tray 62.

  A second reading unit 43 (Contact Image Sensor (CIS)) built in the document conveying unit 42 passes under the second reading unit (CIS) 43 and moves to the document discharge tray 62. The back side of the discharged original paper is illuminated, the reflected light from the back side of the original paper is received, and the image on the back side of the original paper is read.

  The original paper image read by the CCD 48 and the CIS 43 in this way is input to the laser exposure device 23 of the image forming apparatus 1, and the image is recorded on the recording paper in the image forming apparatus 1, and this recording paper is output as a copy original. Is done.

  Next, the configuration of the paper feeding device 71 of the present embodiment built in the large capacity paper feeding cassette 14 will be described in detail. The paper feeding device 71 stacks and stores a large amount of recording paper, pulls out the recording paper one by one, and sends it out to the paper transport path 33 (shown in FIG. 1).

  FIG. 2 is a perspective view showing the appearance of the sheet feeding device 71 of the present embodiment as viewed from the front side obliquely from above. The paper feeding device 71 has a drawer housing 71a, and the main part of the paper feeding device 71 is provided inside the drawer housing 71a. The drawer housing 71a is supported by a well-known mechanism combining rollers and rails (not shown), for example, so as to be reciprocally movable in the arrow directions Ma and Mb within the main body of the large-capacity paper feed cassette 14, so The paper feeding device 71 can be taken in and out of the accommodation space inside the main body of the paper cassette 14. In a state where the paper feeding device 71 is pulled out from the accommodation space inside the main body of the large-capacity paper feeding cassette 14, the sheet bundle is replenished to the paper feeding device 71 and stacked. In addition, in a state where the paper feeding device 71 is pushed into the housing space inside the main body of the large capacity paper feeding cassette 14, the paper bundle 71 sequentially draws out the sheets of the paper bundle to the paper transport path 33 of the image forming apparatus 1. And fed.

  3 and 4 are a plan view and a front view showing the paper feeding device 71 of the present embodiment. As shown in FIGS. 3 and 4, the sheet feeding device 71 is disposed on the outer frame 72, the bottom plate 73, the sheet stacking plate 74 disposed on the inner side of the outer frame 72, and one end upper side of the outer frame 72. A paper drawer 75 and the like are provided.

  The sheet stacking table 74 is used for stacking a large amount of recording sheets (sheet bundle) and is provided inside the outer frame 72 so as to be moved up and down. The paper stacking base 74 is formed with an opening 74 a that is long in the recording paper drawing direction (paper transport direction) E. The paper trailing edge guide 76 is supported on the bottom plate 73 so as to be reciprocally movable along the recording paper drawing direction E, and protrudes upward through the opening 74 a of the paper stacking table 74.

  Recesses 74b are formed on both sides of the sheet stacking table 74, and assist ducts 77 and 78 are disposed in the respective recesses 74b. The assist ducts 77 and 78 are supported on both sides of the outer frame 72 so as to be able to reciprocate in a direction orthogonal to the drawing direction E, and are moved in conjunction with each other so as to approach each other or to be separated from each other. The

  The paper drawing section 75 includes four endless paper conveyance belts 81, a set of rollers 82 and 83 that bridge the paper conveyance belts 81, an intake / exhaust fan 84, an intake duct 85, an exhaust duct 86, and the like. Yes. Each paper transport belt 81 is formed with a large number of air holes 81 a, and air is sucked from the air holes 81 a of each paper transport belt 81 to the intake / exhaust fan 84 through the intake duct 85, and each paper transport belt 81. As a result, the recording sheets of the sheet bundle on the sheet stacking board 74 are sucked and conveyed. Further, the air exhausted from the intake / exhaust fan 84 is guided through the exhaust duct 86 and is blown out from the exhaust duct 86 to the inside of the outer frame body 72 in the direction opposite to the extraction direction E (rearward).

  Note that the entrance / exit side of the storage space in which the paper feeding device 71 is taken in and out is the front side, and the back side of the storage space is the rear side. Further, the recording paper drawing direction (paper conveyance direction) E is the front, and the direction opposite to the drawing direction E is the rear.

  FIG. 5 is a perspective view showing the outer frame body 72, the bottom plate 73, the paper stacking board 74, and the like viewed obliquely from the rear side with the paper drawer portion 75 removed.

  As shown in FIG. 5, assist fans 79 and 80 are provided outside the assist ducts 77 and 78, respectively. Each of the assist ducts 77 and 78 is a hollow body and has a ventilation path therein. Air sucked by each of the assist fans 79 and 80 is sent to the ventilation paths of the respective assist ducts 77 and 78. The air is blown out to the inside of the outer frame 72 from the blowout ports 77a and 78a of the assist ducts 77 and 78.

  In addition, as shown in FIG. 5, front and rear support members 91 and 92 are fixed to the upper surfaces of the assist ducts 77 and 78, and these support members 91 and 92 contact the outer frame 72. It extends from the vicinity of the contact plate 72b to the rear ends of the assist ducts 77 and 78. Respective sheet regulating members 93 are attached to the front end portions of the supporting members 91 and 92, and these sheet regulating members 93 protrude inward from the assist ducts 77 and 78, respectively.

  Since the support members 91 and 92 are fixed to the upper surfaces of the assist ducts 77 and 78, when the assist ducts 77 and 78 are reciprocated in a direction orthogonal to the pull-out direction E, the support members 91 and 92 are provided. Each sheet regulating member 93 is also reciprocated in a direction orthogonal to the drawing direction E.

  Further, each sheet regulating member 93 is arranged on both outer sides in the direction orthogonal to the drawing direction E with respect to each sheet conveying belt 81. Each sheet conveying belt 81 attracts and conveys the leading end side (the side facing the drawing direction E) of the recording sheet of the sheet bundle, so that each sheet regulating member 93 is opposed to both end portions on the leading end side of the upper surface of the sheet bundle. Will be placed.

  FIGS. 6A and 6B are perspective views showing the vicinity of the respective sheet regulating members 93 attached to the front and rear support members 91 and 92 in an enlarged manner when viewed from below. As shown in FIGS. 6A and 6B, each frame 94 is screwed to each support member 91, 92, and each sheet regulating member 93 is supported by these frames 94.

  FIG. 7A is a cross-sectional view schematically showing the paper regulating member 93 and the frame 94 as viewed from the side, and FIG. 7B is a schematic view of the paper regulating member 93 and the frame 94 from the above. FIG. As shown in FIGS. 7A and 7B, the sheet regulating member 93 is provided at a substantially trapezoidal flat plate portion 93a and both ends of the upper surface of the flat plate portion 93a (both ends of the surface facing away from the sheet bundle). A pair of inclined ribs 93b, a shaft 93c provided near the bottom of the trapezoidal flat plate portion 93a, and a lever 93d protruding from the shaft 93c. The frame 94 has a pair of side plates 94a, a back plate 94b, and a bottom plate 94c.

  The sheet regulating member 93 is rotatably supported through the holes of each side plate 94a through both ends of the shaft 93c of the sheet regulating member 93. Further, the tip of the lever 93 d of the paper regulating member 93 is connected to the back plate 94 b of the frame 94 via the coil spring 95, and the lever 93 d is pulled by the coil spring 95. As a result, the shaft 93c is pulled in a direction perpendicular to the shaft 93c. The lever 93d rotates about the shaft 93c until it stops in the direction pulled by the coil spring 95, and the flat plate portion 93a also rotates and stops. As a result, as shown in FIG. 7A, the sheet regulating member 93 is held facing and parallel to the upper surface of the sheet bundle stacked on the sheet stacking board 74.

  Further, since the paper regulating member 93 is only held in a stopped state by the urging force of the coil spring 95, the paper regulating member 93 resists the urging force of the coil spring 95 as shown in FIGS. Thus, it can be rotated in the vertical direction around the shaft 93c. As shown in FIG. 8A, when the sheet regulating member 93 is rotated approximately 90 ° upward, the inclined ribs 93b at both ends of the upper surface of the flat plate portion 93a are brought into contact with the contact portions 91a and 92a of the support members 91 and 92. Further, the rotation of the sheet regulating member 93 beyond about 90 ° in the upward direction is prevented. Further, as shown in FIG. 8B, when the sheet regulating member 93 is rotated approximately 90 ° downward, the lower surface of the flat plate portion 93a comes into contact with the end portion of the bottom plate 94c of the frame 94, and approximately 90 ° downward. The sheet regulating member 93 is prevented from rotating beyond the limit. Here, the urging force of the coil spring 95 is adjusted so that the paper regulating member 93 starts to rotate when a force of 5 (g force) is applied to the tip of the paper regulating member 93.

  Here, when stacking a sheet bundle on the sheet stacking board 74, both ends of the sheet bundle may come into contact with each sheet regulating member 93. However, if both ends of the sheet bundle contact, as shown in FIG. Since each sheet regulating member 93 rotates downward and the space between each sheet regulating member 93 is widened, each sheet regulating member 93 does not cause a harmful effect on the stacking operation of the sheet bundle. Further, when the sheet bundle is removed from the sheet stacking board 74, even if both ends of the sheet bundle come into contact with each sheet regulating member 93, each sheet regulating member 93 rotates upward as shown in FIG. Since the gaps between the sheet regulating members 93 are wide open, the sheet regulating members 93 do not adversely affect the work of removing the sheet bundle. Then, even if each paper regulating member 93 once rotates in the vertical direction, each paper regulating member 93 is rotated back by the urging force of each coil spring 95, and the paper regulating member 93 is rotated as shown in FIG. The sheet stack placed on the sheet stacking board 74 is held parallel to and opposed to the upper surface of the sheet bundle.

  Further, as shown in FIG. 7A, the inclined ribs 93b provided at both ends of the upper surface of the flat plate portion 93a of the sheet regulating member 93 are formed on the sheet stacking board 74 in the direction orthogonal to the drawing direction (paper conveying direction) E. The closer to the center of the stacked sheet bundle, the closer to the upper surface of the sheet bundle. That is, each inclined rib 93b is inclined so as to be lowered at the center side of the sheet bundle. For this reason, when both ends of the sheet bundle come into contact with each inclined rib 93b of each sheet regulating member 93 when the sheet bundle is stacked on the sheet stacking board 74, both ends of the sheet bundle slide quickly on each inclined rib 93b. Each sheet regulating member 93 is pushed away, and the stacking operation of the sheet bundle becomes easy.

  Further, the rear end portion 93e of each paper regulating member 93 facing the rear end side of the paper bundle is such that the paper in the drawing direction E becomes closer to the center from the side edge of the paper bundle in the direction orthogonal to the drawing direction (paper transport direction) E. Inclined to approach the tip of the bundle. For this reason, a wide space is opened on the side of the rear end portion 93e of each paper regulating member 93, and the recording paper can be easily taken in and out of the paper stacking base 74 from the side opposite to the drawing direction E.

  Further, the sheet regulating member 93 is formed of a synthetic resin in a flat plate shape and has a large strength, so that it is damaged even if both ends of the sheet bundle repeatedly contact or are directly operated by an operator. There is no.

  Next, the raising / lowering mechanism of the paper stacking base 74 will be described. As shown in FIG. 5, two protruding pieces 74 c are formed on both sides of the paper stacking base 74, and each protruding piece 74 c protrudes from the opening 72 a on both sides of the main frame 72. On one side of the main frame 72, two wires 87 are connected to the protruding pieces 74 c on one side of the paper stacking base 74, and each wire 87 is hung around a plurality of driven pulleys 88 and drawn around a take-up pulley 89. It is connected. On the other side of the main frame 72, the other two wires 87 are connected to the protruding pieces 74c on the other side of the sheet stacking table 74, and the other wires 87 are connected to a plurality of other driven pulleys 88. It is drawn around and connected to another take-up pulley 89. Each winding pulley 89 is fixed to both ends of a common shaft 97 that is rotatably supported. The shaft 97 is rotationally driven by a pulse motor 98 to rotate each winding pulley 89, and each wire 87 is wound to each winding 87. It is wound around the pulley 89 and is fed out from each winding pulley 89.

  When the shaft 97 is rotationally driven by the pulse motor 98 and each take-up pulley 89 is rotated in the clockwise direction, each wire 87 is taken up by each take-up pulley 89, and the sheet stacking table 74 is raised, and each take-up pulley 89 is turned up. When the take-up pulley 89 is rotated in the counterclockwise direction, each wire 87 is fed out from each take-up pulley 89, and the sheet stacking table 74 is lowered. Further, the rotation angle of the take-up pulley 89 that is rotationally driven by the pulse motor 98 and the height of the paper stacking base 74 are in a corresponding relationship. Therefore, by controlling the rotation direction and rotation angle of the pulse motor 98, the height of the sheet stacking base 74 can be adjusted and set.

  Next, a mechanism for detecting the height position of the upper surface of the sheet bundle on the sheet stacking board 74 will be described. As shown in FIGS. 2, 3, and 5, the contact member 101 is supported on the upper portion of the paper trailing edge guide 76 so as to be reciprocally rotatable in the arrow rotation directions Qa and Qb. The member 101 is reciprocated. When the paper feeding device 71 is pulled out from the storage space inside the main body of the large-capacity paper feeding cassette 14, the position switching unit 102 keeps the contact member 101 substantially vertical in conjunction with the drawing operation of the paper feeding device 71. Rotate in the arrow rotation direction Qa and retract. In this state, the sheet bundle can be replenished and set on the sheet stacking board 74 without being caught on the contact member 101. Further, when the paper feeding device 71 is pushed into the storage space inside the main body of the large capacity paper feeding cassette 14, the position switching unit 102 makes the contact member 101 substantially horizontal in conjunction with the pushing operation of the paper feeding device 71. Rotate it in the arrow rotation direction Qb until it falls. In this state, when the paper stacking base 74 is raised and the contact member 101 comes into contact with the rear end portion of the upper surface of the sheet bundle, the contact member 101 prevents the rear end portion of the recording sheets of the paper bundle from being lifted.

  9 is a perspective view showing a state of the contact member 101 and the position switching unit 102 when the paper feeding device 71 is pulled out, and FIG. 10 is a diagram of the contact member 101 when the paper feeding device 71 is pushed in. 3 is a perspective view showing a state of the position switching unit 102. FIG.

  As shown in FIGS. 9 and 10, the contact member 101 is provided on the upper side of the front side wall of the paper rear end guide 76 facing the recording paper drawing direction E. The contact member 101 includes a shaft portion 101a, a column portion 101b, two rollers 101e, a fan-shaped shielding piece 101f fixed around the shaft portion 101a, and the shaft portion 101a and the contact member 101. Is provided with a torsion spring 103 or the like that urges in the arrow rotation direction Qb.

  Further, an optical sensor 104 is disposed below the shaft portion 101 a and is fixed to the front side wall of the paper trailing edge guide 76. The optical sensor 104 is a light emitting element and a light receiving element that are arranged to face each other with a gap therebetween, and detects the shielding piece 101f when the shielding piece 101f that rotates together with the contact member 101 is between the light emitting element and the light receiving element. .

  The position switching unit 102 includes a rotating member 105, a rod 106, a coil spring 107, and the like. The position switching unit 102 moves the contact member 101 away from the upper surface of the sheet bundle in conjunction with the loading / unloading operation of the sheet feeding device 71. Or abut.

  Here, as shown in FIG. 9, in the state where the paper feeding device 71 is pulled out, the rod 106 is moved in the arrow direction Ma by the urging force of the coil spring 107, the rotating member 105 rotates and rises, and the arm of the rotating member 105. The portion 105c comes into contact with the column portion 101b of the contact member 101, and the contact member 101 rises substantially vertically and retreats to the separation retreat position. Further, the shielding piece 101 f of the shaft portion 101 a protrudes in the pull-out direction (forward) E and moves away from the optical sensor 104.

  As shown in FIG. 10, when the sheet feeding device 71 is pushed in, the entire sheet feeding device 71 is accommodated in the accommodating space inside the main body of the large-capacity sheet feeding cassette 14, and one end of the rod 106 is fed to the large-capacity sheet. Abutting on the main body frame of the cassette 14, the rod 106 moves in the arrow direction Mb, the rod 106 pushes the rotating member 105, and the rotating member 105 rotates against the urging force of the coil spring 107 and tilts. Then, the arm portion 105c of the rotating member 105 moves away from the position of the column portion 101b of the abutting member 101, the abutting member 101 is biased in the arrow rotation direction Qb by the torsion spring 103, and the abutting member 101 is moved. It rotates in the arrow rotation direction Qb and falls to the standby position below the horizontal. The shielding piece 101f of the shaft portion 101a rotates in the arrow rotation direction Qb and passes between the light emitting element and the light receiving element of the optical sensor 104.

  Thereafter, the sheet stacking table 74 is raised, the rear end of the upper surface of the sheet bundle pushes up the contact member 101, and the contact member 101 is slightly inclined above the horizontal suction position (the uppermost layer of the sheet bundle). The recording paper is lifted up to the height of suction). Further, the shielding piece 101f of the shaft portion 101a rotates in the arrow rotation direction Qa, enters between the light emitting element and the light receiving element of the optical sensor 104, and is detected by the optical sensor 104.

  11A, 11 </ b> B, and 11 </ b> C illustrate the positional relationship between the separation / retraction position, the standby position, and the suction position of the contact member 101, the shielding piece 101 f of the contact member 101, and the optical sensor 104. Show.

  When the paper feeding device 71 is pulled out, as shown in FIG. 11A, the abutting member 101 rises substantially vertically and is in the separated retreat position, and the shielding piece 101f of the shaft portion 101a is in the pulling direction (front) E. It protrudes toward the center of the optical sensor 104 and is out of the space between the light emitting element 104a and the light receiving element 104b. For this reason, the shielding piece 101 f is not detected by the optical sensor 104.

  Immediately after the sheet feeding device 71 is pushed in, as shown in FIG. 11B, the contact member 101 falls below the horizontal position and is in a standby position, and the shielding piece 101f of the shaft portion 101a is an optical sensor. 104 is separated from between the light emitting element 104a and the light receiving element 104b. For this reason, the shielding piece 101 f is not detected by the optical sensor 104.

  Further, when the rear end portion of the upper surface of the sheet bundle pushes up the contact member 101, the contact member 101 is lifted slightly obliquely upward from the horizontal position as shown in FIG. The shielding piece 101f of the portion 101a is located between the light emitting element 104a and the light receiving element 104b of the optical sensor 104. For this reason, the shielding piece 101 f is detected by the optical sensor 104.

  Therefore, based on the detection output of the optical sensor 104, it can be determined that the contact member 101 is in the suction position, the separation / retraction position, or the standby position.

  Next, the configuration of the paper drawer 75 will be described in detail. FIG. 12 is a perspective view showing the paper drawer portion 75 as viewed obliquely from the upper front. FIG. 13 is a perspective view showing the paper drawer portion 75 as viewed obliquely from above and behind, and FIG. 14 is a perspective view showing the paper drawer portion 75 as seen from diagonally below and rear.

  As shown in FIGS. 12, 13, and 14, the paper drawing unit 75 includes four endless paper conveyance belts 81, a set of rollers 82 and 83 that bridge the paper conveyance belts 81, an intake / exhaust fan 84, An intake duct 85 and an exhaust duct 86 are provided.

  The intake duct 85 is a hollow body, and has an air suction path that is long in a direction orthogonal to the drawing direction (paper conveyance direction) E, and one end 85 a thereof is connected to the intake / exhaust fan 84. Then, as indicated by an arrow F, air is sucked from the air suction path of the intake duct 85 to the intake port (not shown) of the intake / exhaust fan 84 through the one side end 85a.

  In addition, air suction ports 111 (shown in FIG. 15) that overlap with the plurality of air holes 81 a of the paper transport belt 81 are provided on the lower surface 85 g of the intake duct 85 for each paper transport belt 81. Each air suction port 111 is connected to the air suction path of the intake duct 85. When the air in the intake duct 85 is sucked by the intake / exhaust fan 84, external air flows into the air suction ports 111 on the lower surface 85g of the intake duct 85 and the air holes 81a of the paper transport belts 81.

  Furthermore, the front end portion 85c and the rear end portion 85d of the intake duct 85 are formed with respective recesses 85h, and the rollers 82 and 83 are disposed in these recesses 85h so as to be rotatably supported. The output shaft of the transport motor 112 is connected to the shaft of the front roller 82. Each paper transport belt 81 is bridged between the rollers 82 and 83. The front roller 82 is rotationally driven in the arrow direction D by the transport motor 112, the rear roller 83 is driven to rotate, and each paper transport belt 81 rotates in the arrow direction D.

  The exhaust duct 86 is also a hollow body and has a long ventilation path in a direction orthogonal to the drawing direction E. One end 86a of the exhaust duct 86 is connected to the intake / exhaust fan 84, as indicated by an arrow K. Air is sent from the exhaust port (not shown) of the intake / exhaust fan 84 to the ventilation path of the exhaust duct 86 through the one end 86a of the exhaust duct 86.

  In addition, a plurality of exhaust holes 86 b communicating with the ventilation path of the exhaust duct 86 are formed in the inner wall surface 86 d of the exhaust duct 86. An inner wall surface 86 d of the exhaust duct 86 is provided so as to overlap with an outer surface of the outer frame body 72 (shown in FIG. 5), and each exhaust hole 86 b of the exhaust duct 86 is notched in the contact plate 72 b of the outer frame body 72. It faces the inside of the outer frame 72 through 72c. When air is sent from the intake / exhaust fan 84 to the exhaust duct 86, the air is blown out from the exhaust holes 86 b toward the inside (rear) of the outer frame 72.

  In addition, a sheet conveyance opening ES is formed between the upper end surface 86 e of the exhaust duct 86 and each conveyance belt 81.

  Next, operations and operations of the sheet feeding device 71 will be described. When the paper feeding device 71 is pulled out from the storage space inside the main body of the large-capacity paper feeding cassette 14, the abutting member 101 is substantially shortened by the position switching unit 102 in conjunction with the pulling-out operation of the paper feeding device 71 as described above. It is rotated in the arrow rotation direction Qa until it becomes vertical and retracts.

  In this state, the paper trailing edge guide 76 is moved rearward to widen the space between the paper trailing edge guide 76 and the rectangular plate 72b of the main frame 72, and the assist ducts 77 and 78 are separated from each other. To open a wide space between the assist ducts 77 and 78. At this time, since the contact member 101 is retracted substantially vertically, the sheet bundle can be supplemented and stacked on the sheet stacking table 74 without being caught on the contact member 101.

  Further, when stacking a sheet bundle on the sheet stacking board 74, even if both ends of the sheet bundle contact each sheet regulating member 93, each sheet regulating member 93 rotates downward as shown in FIG. 8B. There is no negative effect on the stacking operation of the sheet bundle.

  Subsequently, the sheet trailing edge guide 76 is moved in the drawing direction E, the trailing edge of the sheet bundle is pushed in the drawing direction E by the sheet trailing edge guide 76, and the sheet bundle is slid and moved on the sheet stacking board 74, so that the sheet bundle is moved. The leading edge and the trailing edge of the sheet bundle are sandwiched between the trailing edge guide 76 and the rectangular plate 72b of the main frame body 72 and positioned. Further, the assist ducts 77 and 78 are moved in a direction approaching each other so that both ends of the sheet bundle are sandwiched between the assist ducts 77 and 78 and positioned. As the assist ducts 77 and 78 move, the sheet restricting members 93 supported on the upper sides of the assist ducts 77 and 78 also move in a direction approaching each other. Are arranged opposite to both end portions on the front end side of the upper surface of the sheet bundle.

Thereafter, when the paper feeding device 71 is pushed into the storage space inside the main body of the large-capacity paper feeding cassette 14, the position switching unit 102 makes contact with the pushing operation of the paper feeding device 71 as described above. The member 101 is rotated and tilted in the arrow rotation direction Qb. At this time, as shown in FIG. 11B, the contact member 101 falls below the horizontal and moves to the standby position, so that the shielding piece 101f is not detected by the optical sensor 104. In this state, when each take-up pulley 89 is rotated by the pulse motor 98 and the sheet stacking base 74 is raised and the upper surface of the sheet bundle is raised, the rear end portion of the upper surface of the sheet bundle contacts the contact member 101. The contact member 101 is pushed up and the contact member 101 is pushed up, and the rear end portion of the upper surface of the sheet bundle is pressed by the contact member 101 to prevent the recording sheet rear end portion of the sheet bundle from being lifted. As the contact member 101 is pushed up, the contact member 101 moves to the suction position as shown in FIG. 11C, and the shielding piece 101f is detected by the optical sensor 104. In response to this, the pulse motor 9 8 is stopped. As a result, the separation distance between the upper surface of the sheet bundle and each sheet conveying belt 81 is about 12 mm, and the height position of the upper surface of the sheet bundle is suitable for adsorbing the uppermost recording sheet of the sheet bundle by each sheet conveying belt 81. Adjusted to the suction position.

  When the uppermost recording sheet of the sheet bundle is in contact with the contact member 101, each sheet regulating member 93 is positioned at a height of about 2 to 4 mm from the upper surface of the sheet bundle. That is, each sheet regulating member 93 is positioned on each sheet conveying belt 81 side with a certain distance from both end portions of the upper surface of the sheet bundle that has reached the suction position. Further, since both ends of the sheet bundle are positioned between the assist ducts 77 and 78, the sheet regulating members 93 supported on the upper side of the assist ducts 77 and 78 are located on the center side from both ends of the sheet bundle. Project about 12-13 mm. Accordingly, each sheet regulating member 93 is positioned at a height that faces both end portions on the front end side of the upper surface of the sheet bundle and is separated from the upper surface of the sheet bundle by about 2 to 4 mm.

  In this state, air is sent from the assist fans 79 and 80 to the assist ducts 77 and 78 as shown in the schematic cross-sectional view of FIG. 15, and the air is exhausted from the exhaust holes 77a and 78a of the assist ducts 77 and 78. Air is blown onto the upper layers of the both end surfaces of the sheet bundle on the sheet stacking table 74 to infiltrate the air between the recording sheets, and the recording sheets are dispersed. Further, air is sent from the intake / exhaust fan 84 to the exhaust duct 86, and the air is blown from the exhaust holes 86b of the exhaust duct 86 to the upper layer of the front end surface of the sheet bundle so that the air enters between the recording sheets. Disperse the recording paper. As a result, the adhesion of each recording sheet in the upper layer of the sheet bundle is reduced, the recording sheet can be easily pulled out from the sheet bundle, and the recording sheets can be pulled out one by one.

  Then, air is sucked from the intake duct 85 to the intake / exhaust fan 84, and the air is sucked through the air holes 81 a of the respective paper transport belts 81 and the air suction ports 111 on the lower surface 85 g of the suction duct 85, Adhere the uppermost recording paper to the surface. At this time, since the uppermost recording sheet of the sheet bundle is positioned at the suction position where the uppermost recording sheet comes into contact with the contact member 101, the uppermost recording sheet can be quickly adsorbed to the surface of each sheet conveying belt 81.

  At the same time, the rollers 82 and 83 are rotated by the transport motor 112 to rotate the respective paper transport belts 81 and the uppermost recording paper is pulled out in the pulling direction E by the respective paper transport belts 81 to form an image on the recording paper. The sheet is conveyed to the sheet conveyance path 33 through the conveyance roller 31 of the apparatus 1. At this time, the recording paper on the upper layer of the sheet bundle is levitated by blowing air from the exhaust holes 77 a and 78 a of the assist ducts 77 and 78 and blowing air from the exhaust holes 86 b of the exhaust duct 86. Both end portions on the leading end side of the recording sheet abut on each sheet regulating member 93. Further, the vicinity of the center of the recording sheet is strongly adsorbed by each sheet conveying belt 81. For this reason, as shown in FIG. 16A, both end portions on the leading end side of the recording paper P are pressed, the vicinity of the center of the recording paper P rises, and the recording paper P is bent in a mountain shape.

  As shown in FIG. 15, since the sheet regulating member 93 is higher than the upper end of the contact plate 72b of the outer frame 72, the recording sheet P is pulled out in the pulling-out direction E by each sheet conveying belt 81. Then, both end portions of the recording paper P pass over the contact plate 72b of the outer frame 72 while being in sliding contact with the respective paper regulating members 93, and the recording paper P further passes over the upper end surface 86e of the exhaust duct 86 and the respective conveying belts. The paper is conveyed through the paper conveyance port ES between the two.

  In the state in which both end portions of the recording paper P are in contact with the respective paper restricting members 93, the respective paper restricting members 93 are slightly rotated upward and the recording paper P becomes thicker or the rigidity of the recording paper P is increased. The higher the is, the larger the rotation angle of each sheet regulating member 93 is. Therefore, even if the recording paper P is thick or the recording paper P has high rigidity, both end portions of the recording paper P are not strongly pressed by the paper restricting members 93, and the respective paper restricting members 93 and The resistance of the recording paper P caused by the sliding contact is not increased. The recording paper P can be quickly pulled out by each paper conveying belt 81.

  Thereafter, the suction of air by the suction / exhaust fan 84 and the rotation of the rollers 82 and 83 by the transport motor 112 are temporarily stopped, and when the drawing of the recording paper P from each of the paper transport belts 81 is completed, the suction / exhaust fan 84 is completed. Air suction and rotation of the rollers 82 and 83 by the conveyance motor 112 are resumed, the uppermost recording paper P is attracted to the surface of each paper conveyance belt 81, and the recording paper P is pulled out by each paper conveyance belt 81. In the direction E, the recording paper P is conveyed to the conveying roller 31, and thereafter, similarly, the uppermost recording paper P is repeatedly adsorbed on the surface of each paper conveying belt 81, and the recording paper P is drawn in the drawing direction E by each paper conveying belt 81. Pull out and carry.

Further, when the recording paper is repeatedly drawn from the paper bundle, the height of the paper bundle is lowered. At this time, descends abutment member 101 than the suction position, the shield piece 101f is not detected by the optical sensor 104, the rotation of the pulse motor 9 8 is resumed, the sheet stacking plate 74 is raised, the sheet bundle The upper surface is raised again to the suction position. When the shielding piece 101f is detected again by the optical sensor 104, the pulse motor 9 8 is stopped. Such a rise of the paper stacking table 74 is repeated, so that the uppermost recording paper of the paper bundle is always positioned at the suction position.

  Here, in a low-humidity environment, the recording paper P in the sheet bundle may lose moisture, and the recording paper P in the upper layer of the sheet bundle may curl. For example, as shown in FIG. 16B, the leading ends of a plurality of recording sheets P in the upper layer of the sheet bundle may curl and warp. In such a state, if air is blown from the exhaust holes 86b of the exhaust duct 86 to the upper layer of the front end surface of the sheet bundle, the air is received by the back surface on the front end side of each recording paper P that is warped. The leading edge of each recording sheet P floats and air does not enter between the recording sheets P, and each recording sheet P is attracted and transported by the respective sheet transport belts 81 while being overlapped. Double feed occurs.

  However, in the present embodiment, each sheet regulating member 93 is located at a height that faces both end portions on the leading end side of the upper surface of the sheet bundle and is separated by about 2 to 4 mm from the upper surface of the sheet bundle. Even if a plurality of recording papers P in the upper layer of the paper bundle are curled and warped, both end portions of each recording paper P abut against each paper regulating member 93 as shown in FIG. The warping of P is restricted, and each recording sheet P is generally kept flat. For this reason, the air from each exhaust hole 86b of the exhaust duct 86 quickly enters between the recording sheets P, and the recording sheets P are dispersed. It can be adsorbed and pulled out one by one. Then, the upper recording sheet P of the sheet bundle floats, both end portions on the leading end side of the recording sheet P abut against each sheet regulating member 93, and the vicinity of the center of the recording sheet P is strong by each sheet conveying belt 81. When adsorbed, since the recording paper P has stiffness (rigidity), the recording paper P is bent in a mountain shape as shown in FIG. . As a result, the double feeding of the recording paper P is prevented, and the recording paper P can be quickly pulled out and conveyed.

  Further, as shown in FIG. 16A, when each recording sheet P is bent in a mountain shape, the gap between the recording sheets P is easily enlarged near the center of each recording sheet P, and each exhaust hole 86 b of the exhaust duct 86. From the air quickly enters between the recording papers P, and the papers vary well.

  Further, since each sheet regulating member 93 only abuts on the uppermost recording sheet P of the sheet bundle, each sheet regulating member 93 does not cause a trouble in conveying the recording sheet P by each sheet conveying belt 81. The recording paper P can be quickly conveyed.

  In the above embodiment, each sheet regulating member 93 is provided at both end portions on the leading end side of the sheet bundle upper surface. However, as shown in FIG. Even when the recording paper P is provided only at the one end portion on the leading end side, the one end portion of each recording paper P abuts on the paper restricting member 93 and the curling of substantially half of each recording paper P is restricted. Almost half of this is kept flat. For this reason, the air from each exhaust hole 86b of the exhaust duct 86 quickly enters between the recording sheets P, and the recording sheets P are dispersed. It can be adsorbed and pulled out one by one.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the example which concerns. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. It is understood.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 2 Document reader 11 Printing part 12 Paper conveyance part 13 Paper supply part 14 Large capacity paper feed cassette (LCC)
71 Paper feeder 72 Outer frame 73 Bottom plate 74 Paper stacking board 75 Paper drawer part 76 Paper rear end guides 77, 78 Assist ducts 79, 80 Assist fan 81 Paper transport belt (paper transport member)
82, 83 Roller 84 Intake / exhaust fan 85 Intake duct 86 Exhaust duct 86b Exhaust hole (air blowing part)
91, 92 Support member 93 Paper restricting member 94 Frame 95 Coil spring

Claims (14)

A sheet feeding device that stacks a sheet bundle on a sheet loading table, sucks air through a sheet conveying member, and sucks and conveys the sheets of the sheet bundle to the sheet conveying member;
An air blowing unit that blows air onto the tip of the sheet bundle;
A sheet regulating member provided on the leading end side of the sheet bundle, which is an end of the upper surface of the sheet bundle in a direction orthogonal to the sheet conveyance direction ,
The sheet feeding device , wherein the sheet regulating member is supported so as to be able to rotate and move in a direction in which the sheet regulating member contacts and separates from the upper surface of the sheet bundle . A sheet feeding device that stacks a sheet bundle on a sheet loading table, sucks air through a sheet conveying member, and sucks and conveys the sheets of the sheet bundle to the sheet conveying member;
An air blowing unit that blows air onto the tip of the sheet bundle;
A sheet regulating member provided on the leading end side of the sheet bundle, which is an end of the upper surface of the sheet bundle in a direction orthogonal to the sheet conveyance direction,
The rear end portion of the paper regulating member facing the rear end side of the paper bundle is closer to the center from the side edge of the paper bundle in a direction orthogonal to the paper transport direction. A sheet feeding device that is inclined so as to approach the tip. A sheet feeding device that stacks a sheet bundle on a sheet loading table, sucks air through a sheet conveying member, and sucks and conveys the sheets of the sheet bundle to the sheet conveying member;
An air blowing unit that blows air onto the tip of the sheet bundle;
A sheet regulating member provided on the leading end side of the sheet bundle, which is an end of the upper surface of the sheet bundle in a direction orthogonal to the sheet conveyance direction,
The sheet feeding device, wherein the sheet regulating member is plate-shaped. A sheet feeding device that stacks a sheet bundle on a sheet loading table, sucks air through a sheet conveying member, and sucks and conveys the sheets of the sheet bundle to the sheet conveying member;
An air blowing unit that blows air onto the tip of the sheet bundle;
A sheet regulating member provided on the leading end side of the sheet bundle, which is an end of the upper surface of the sheet bundle in a direction orthogonal to the sheet conveyance direction,
The portion of the sheet regulating member facing away from the sheet bundle is inclined so as to approach the upper surface of the sheet bundle as it approaches the center of the sheet bundle in a direction orthogonal to the sheet conveyance direction. Paper feeding device to be used. A sheet feeding device according to any one of claims 2 to 4,
The sheet feeding device, wherein the sheet regulating member is supported so as to be able to rotate and move in a direction in which the sheet regulating member contacts and separates from the upper surface of the sheet bundle. The sheet feeding device according to claim 1, 3 or 4,
The rear end portion of the paper regulating member facing the rear end side of the paper bundle is closer to the center from the side edge of the paper bundle in a direction orthogonal to the paper transport direction. A sheet feeding device that is inclined so as to approach the tip. The sheet feeding device according to claim 1, claim 2, or claim 4,
The sheet feeding device, wherein the sheet regulating member is plate-shaped. A paper feeding device according to any one of claims 1 to 3,
The portion of the sheet regulating member facing away from the sheet bundle is inclined so as to approach the upper surface of the sheet bundle as it approaches the center of the sheet bundle in a direction orthogonal to the sheet conveyance direction. Paper feeding device to be used. The sheet feeding device according to claim 1 or 5 ,
An urging portion for holding the sheet regulating member so as to be parallel to the upper surface of the sheet bundle;
The sheet feeding device, wherein the sheet regulating member rotates and moves in a direction in which the sheet regulating member comes in contact with and separates from an upper surface of the sheet bundle against an urging force by the urging unit. The sheet feeding device according to claim 9 ,
The paper restricting member has respective shafts that rotatably support the paper restricting member in a direction in which the paper restricting member comes into contact with or separates from the upper surface of the paper bundle.
The biasing section pulls the axis of the sheet regulating member in a direction perpendicular to the axis to hold the sheet regulating member so as to be parallel to the upper surface of the sheet bundle. apparatus. The sheet feeding device according to claim 1, claim 5, claim 9 or claim 10 ,
The sheet feeding device according to claim 1, wherein the sheet regulating member rotates and moves until the sheet regulating member is orthogonal to the upper surface of the sheet bundle. A sheet feeding device according to any one of claims 1 to 11 ,
The sheet feeding device according to claim 1, wherein the sheet regulating member is disposed at both ends of the upper surface of the sheet bundle in the orthogonal direction. The sheet feeding device according to claim 12 ,
A position detector for detecting that the upper surface of the sheet bundle has reached a specified position;
A raising drive unit that raises the sheet stacking base until the position detecting unit detects that the upper surface of the sheet bundle has reached a specified position;
The sheet feeding device according to claim 1, wherein the sheet regulating member is provided on the sheet conveying member side with a certain distance from the end of the upper surface of the sheet bundle that has reached the specified position. An image forming apparatus comprising: the paper feeding device according to claim 1; and a printing unit that prints an image on a sheet supplied from the paper feeding device.

Images