JP3984564B2 - Paper transport device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
  The present invention is suitable for use in image forming apparatuses such as copying machines, facsimile machines, and various printers, and is applied to a paper feeding apparatus for feeding paper one by one into the apparatus main body. The present invention relates to a sheet conveying apparatus having a shaft mounting structure.
[0002]
[Prior art]
  FIG. 8 (A) described in Patent Document 1 in the past.~ (C)A sheet feeding device 90 as shown in FIG. 2A is an explanatory view of the main part of the paper feeding device 90 in a side view, FIG. 2B is an explanatory view of the front view, and FIG. 2C is an attaching / detaching structure 96 of the roller shaft 921. FIG.
[0003]
  The paper feeding device 90 is used for feeding paper P one by one from a paper bundle loaded in a paper feed cassette 91 provided in an image forming apparatus such as a copying machine and feeding it into the image forming apparatus. As shown in FIG. 8A, a feeding roller 92 that rotates integrally with a roller shaft 921 and is disposed so as to contact the uppermost sheet P on the sheet feeding cassette 91. A guide plate 93 that guides the paper P fed by the feed roller 92 and a pair of upper and lower registration rollers 94 that are disposed opposite to the downstream end of the guide plate 93 are configured. The sheet P fed out by rotation is fed between the registration roller pair 94 via the guide plate 93 and is fed into the image forming apparatus by the rotation of the registration roller pair 94.
[0004]
  By the way, when performing maintenance work such as component replacement and cleaning processing in the paper feeding device 90, a pair of width directions supporting the roller shaft 921 as shown by a two-dot chain line in FIG. It is necessary to remove from the frame 95. For this purpose, a detachable structure 96 as shown in FIG. 8C is adopted at one end of the roller shaft 921.
[0005]
  The detachable structure 96 is concentric with the roller shaft 921 and is connected to a drive shaft 97 penetrated through the frame 95 so as to be non-rotatably fitted to the connecting tube 961 so as to be movable in the axial direction. A roller shaft end portion 962 that is detachably fitted in a stopped state, and a compression coil spring 963 that is externally fitted to the drive shaft 97 between the connecting cylindrical body 961 and the frame 95 are configured. A driving gear 98 is fixed to the base end portion of the driving shaft 97, and driving force from a driving source (not shown) is transmitted to the driving shaft 97 via the driving gear 98.
[0006]
  A locking pin 971 projects from the distal end of the drive shaft 97 in the radial direction, while the coupling cylinder 961 has a cut groove along the center line from the opening edge toward the proximal end. 964 is provided, and the engaging pin 971 is fitted into the cut groove 964 so that the connecting cylinder 961 can move forward and backward in the axial direction in a state of being prevented from coming off.
[0007]
  Further, in the vicinity of the opening in the connecting cylinder 961, an erection pin 965 is provided between the opposed inner peripheral surfaces in the radial direction, while the roller shaft end portion 962 is externally fitted to the erection pin 965. The notch groove 966 is recessed, and the roller shaft 921 is driven via the connecting cylinder 961 by inserting the notch groove 966 into the installation pin 965 in a state where the roller shaft end portion 962 is fitted in the connecting cylinder 961. It is connected to the shaft 97 so as to be integrally rotatable.
[0008]
  According to the detachable structure 96 configured as described above, when the feeding roller 92 is removed from the frame 95, the connecting cylinder 961 is urged by the urging force of the compression coil spring 963 as indicated by an arrow in FIG. If the roller shaft end 962 is disengaged from the connecting cylinder 961 when the drive shaft 97 is moved to the base end side (left side in FIG. 8) against this, the screwing of the frame 95 to the device main body is removed. Thus, the roller shaft 921 can be easily removed without disassembling the paper feeding device 90.
[0009]
[Patent Document 1]
      Japanese Utility Model Publication No. 6-43071
[0010]
[Problems to be solved by the invention]
  By the way, in the attachment / detachment structure 96 of the roller shaft 921 shown in Patent Document 1, the drive shaft 97, the connecting cylinder 961, the compression coil spring 963, and the locking pin 971 and the installation pin 965 provided on the drive shaft 97 are necessary. There is a disadvantage that the number of parts is very large, which increases the part cost and assembly cost.
[0011]
  Further, since the drive shaft 97 and the roller shaft 921 are connected via a connecting cylinder 961 that is movable in the axial direction (that is, unstable to connect both of them concentrically), the drive shaft 97 and the roller There is also a problem that misalignment easily occurs between the shafts 921. In order to solve this problem, it is necessary to improve the machining accuracy, and a new problem is brought about that leads to a rise in machining cost.
[0012]
  The present invention has been made in order to solve the above-described problems, and is capable of minimizing the misalignment of the roller shaft while having a simple structure. It is an object of the present invention to provide a paper transport device having a roller shaft mounting structure that can perform the above operation very easily.
[0013]
[Means for Solving the Problems]
  The invention described in claim 1First and second frames arranged opposite to each other, and the first, A roller shaft having a length spanned between the second frames and having a first end and a second end at both ends, and a sheet mounted on the roller shaft and positioned at the top of the sheet bundle are sequentially A sheet conveying apparatus including a feeding roller for feeding and a transmission gear disposed on the first frame side, wherein a boss portion projects from a central position of the transmission gear, and the boss portion includes the boss portion. A bearing insertion hole into which the first end portion of the roller shaft is removably inserted is drilled. The bearing insertion hole includes a mechanism for transmitting torque of the transmission gear to the roller shaft. , Including a first hole into which the boss portion is inserted, and a first bearing member that receives the boss portion is attached to the first hole, and the second end of the roller shaft is inserted into the second frame. A second hole that receives a second end side of the roller shaft in the second hole; A receiving member is detachably attached, the second end of the roller shaft is a semispherical ball, the second bearing member is externally fitted from the second end of the roller shaft, and the second The hole has a size that allows the roller shaft to be inserted obliquely between the first and second frames in a state where the boss portion is inserted into the first hole.It is characterized by that.
[0014]
  According to this invention, the transmission gear sideFirstFreyAndWhile tilting the roller shaft to avoid interferenceIts first endAnd the other sideSecondendPartThe roller shaftFirstEnd isFirstUntil no interference with the frameSecondFrameSecondInsert into the hole and continue to the roller shaftFirstThe end of the transmission gear bossWith bearingBy inserting into the hole, the roller shaft1st, 2ndMounted between frames.
[0015]
  When removing the roller shaft mounted between the frames, remove the roller shaft.SecondEnd isSecondMove in the axial direction so that it goes outward from the frame.FirstEnd isFirstTilt the roller shaft away from the frame so as not to interfere with the frame, and thenFirstBy pulling in the direction of the end, the roller shaft1st, 2ndIt is removed from between the frames.
[0016]
  And the roller shaft1st, 2ndIn the state of being installed between the frames, the roller shaft isFirstSince the end portion rotates integrally with the transmission gear by the action of a connection structure that is rotated integrally with the transmission gear around the axis, the drive source is driven around the roller axis of the feeding roller via the transmission gear and the roller shaft. As a result, the paper stored in the paper storage unit is fed.
[0017]
  As described above, the rotation of the transmission gear is directly transmitted to the roller shaft without interposing an extra connecting member such as a conventional connecting cylinder or a rotation stopper pin between the roller shaft and the roller gear. The rotation of the transmission gear is transmitted in a state where it does not occur, and as a result, the occurrence of inconveniences that interfere with the sheet feeding due to the eccentric rotation of the feeding roller is effectively prevented.
[0018]
  In addition, since the roller shaft connection structure is greatly simplified as compared with the conventional one, it is possible to ensure the ease of attaching and detaching the roller shaft while contributing to the reduction in the number of parts.
[0019]
  According to a second aspect of the present invention, in the first aspect of the present invention, the roller shaftSecondedgeSide ofThe roller shaft isSecondFrameSecondA detachable retaining structure is provided that prevents movement from moving out of the hole in the outward direction.
[0020]
  According to this invention,1st, 2ndSince the roller shaft mounted between the frames is prevented from being removed by the retaining structure, it is possible to reliably prevent inconvenience that the roller shaft is detached from between the frames during rotation.
[0021]
  According to a third aspect of the present invention, in the first or second aspect of the present invention, the retaining structure is formed by the roller shaft.SecondEndSideIt is characterized by comprising a cut groove formed in the peripheral surface and a stop ring that is detachably mounted in the cut groove.
[0022]
  According to this invention,1st, 2ndBy mounting the stop ring in the notch groove of the roller shaft in a state where the roller shaft is installed between the frames, the roller shaft moves in the axial direction toward the exit direction (the notch groove moves the frame from the inside of the frame. The movement of the roller shaft to the outside is restricted, and this prevents the roller shaft from falling off reliably.
[0023]
  When removing the roller shaft installed between the pair of frames, the stop ring may be removed from the roller shaft. In this way, the roller shaft can be moved in the axial direction and can be removed from the frame.
[0024]
  As described above, the roller shaft retaining structure is constituted by the notch groove of the roller shaft and the stop ring that is detachably attached to the notch groove, thereby achieving the simplification of the structure and ensuring the reliability of the roller shaft. Secures the removal effect.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
  FIG. 1 is a perspective view showing an embodiment of a copying machine to which a paper conveying apparatus according to the present invention is applied. As shown in this figure, a copying machine (image forming apparatus) 10 is formed by mounting a lid 12 having a paper feed structure on an upper surface opening of a box-shaped device body 11.
[0026]
  In the apparatus main body 11, an optical system (not shown) that reads a document image of a sheet fed by a sheet feeding structure, a photosensitive drum that develops a developed document read by the optical system onto a predetermined sheet as a toner image, and development A developing unit (not shown) provided with a device such as an apparatus, a fixing unit (not shown) provided with a fixing roller or the like for fixing a sheet on which a toner image has been transferred by the developing unit, and a transfer sheet are stacked and stored. An unillustrated paper feed unit equipped with a paper feed cassette and the like is internally provided.
[0027]
  The sheet fed from the sheet feeding unit is sent to the developing unit through a predetermined conveyance path, where the toner image from the peripheral surface of the photosensitive drum (this toner) is received from the developing device. The image is formed by once forming an electrostatic latent image on the peripheral surface of the photosensitive drum based on image data read by the optical system, and supplying toner to the electrostatic latent image). After the development process is performed and the heat fixing process is performed by the fixing roller in the fixing unit, the paper is discharged toward a paper discharge unit (not shown) provided on one side surface of the apparatus main body 11.
[0028]
  The lid 12 is provided with a paper feeding portion 13 for feeding paper to one side, and obliquely upward from the paper feeding portion 13 toward the other side of the lid 12. A feed tray (paper storage unit) 14 projecting from the feed tray 14 and a paper discharge tray 15 formed over substantially the entire surface of the lid 12 below the feed tray 14 are provided. A pair of paper width setting members 141 in the width direction are provided at the base end portion (left side in FIG. 1) of the feeding tray 14, and between the pair of paper width setting members 141 according to the size of the paper to be read. The paper is positioned on the feeding tray 14 by adjusting the inner dimension.
[0029]
  The sheet feeding unit 13 includes a pair of width direction frame plates 131, an openable and closable top plate 132 installed between the upper edge portions of the frame plate 131, and the side opposite to the feeding tray 14 between the frame plates 131. The sheet feeding device 20 (see FIG. 2) according to the present invention is mounted in a space surrounded by a back plate 133 that covers the surface of the sheet. A feeding port for drawing the paper placed on the feeding tray 14 into the paper feeding unit 13 in an opening that is surrounded by the pair of frame plates 131 and the top plate 132 and that faces the back plate 133. 135Is formed.Incidentally, in this embodiment, the right frame plate 131 in FIGS. 1 to 3 and FIG. 6 to be referred to later is the first frame plate according to the present invention, and the left frame plate 131 is the second frame plate according to the present invention. It is a frame board.
[0030]
  A plurality of stacked sheets placed on the feeding tray 14 in a state of being positioned by the sheet width setting member 141 are one by one in the sheet feeding unit 13 by driving the sheet feeding device 20. The image on the original surface is optically read by an optical system (not shown).
[0031]
  2 and 3 are perspective views showing the sheet feeding unit 13 in a state where the top plate 132 and the back plate 133 are removed for explaining the mounted state of the sheet feeding device 20, and FIG. FIG. 3 is a diagram viewed from the right side, and FIG. 3 is a diagram viewed from the right side. 4 is a perspective view showing the paper feeding device 20 mounted on the paper feeding unit 13. FIG. 4A is a state where the paper feeding unit is removed from the drive unit, and FIG. The state where the paper feeding unit is mounted on the drive unit is shown.
[0032]
  As shown in these drawings, the paper feeding device 20 includes a paper feeding unit 30 that feeds the paper P placed on the feeding tray 14 into the apparatus main body 11, and a drive that drives the paper feeding unit 30. The unit 60 is provided.
[0033]
  The sheet feeding unit 30 includes a roller shaft 31 installed between a pair of frame plates 131 in the width direction, a casing 40 attached to a central portion of the roller shaft 31, and a feeding roller supported by the casing 40. 50 and a stopper 39 attached to the feeding roller 50. 2 and 3, the roller shaft 31 is located between the pair of frame plates 131 in the width direction and slightly downstream of the sheet width setting member 141 (the left side in FIG. 2, the right side in FIG. 3). ). As shown in FIG. 4, the roller shaft 31 includes a roller shaft main body 32, a flat key 33 formed at the right end of the roller shaft main body 32 in FIG. 4, and a cut groove 34 formed at the left end. It is configured with.
[0034]
  The flat key 33 is connected to one end of the roller shaft 31 (1st end, The right end portion in FIG. 4) is detachably attached to the drive unit 60 via the bearing member 21, and the cut groove 34 is a roller fitted into the frame plate 131 via the bearing member 21. The other end of the shaft 31 (The second end,This is for attaching a stop ring (a retaining piece) 22 for retaining to the left end portion in FIG.
[0035]
  As the bearing member 21, a first bearing member 211 into which a flat key 33 formed at the right end portion in FIG. 4 of the roller shaft 31 is inserted and a second bearing member 212 into which the left end portion is inserted are adopted. Yes. The outer diameter of these bearing members 21 is set so that the outer diameter can be fitted into a fitting insertion hole 134 (described later) of each frame plate 131 in a sliding state. The first bearing member 211 has a circular hole 213 that is fitted around the boss 642 of the transmission gear 64 at the center position.
[0036]
  In contrast,SecondThe bearing member 212 is formed with a circular bearing hole 214 whose inner diameter is set so that the bearing member 212 can be externally fitted to the roller shaft 31 in a sliding contact state. In particular, the bearing hole 214 has a trumpet-shaped opening on the side facing the sheet feeding portion 13, and thereby the inner diameter dimension gradually decreases from the opening toward the inside of the hole. The reason for this is to make it easier to insert the roller shaft 31 in an oblique state into the bearing hole 211 (see FIG. 6A). The bearing hole 214 is not limited to the trumpet shape, and may have the same inner diameter dimension over the entire length in the hole center direction.
[0037]
  Further, a semicircular spherical portion 35 formed in a semispherical shape is formed at the end of the roller shaft 31 on the side where the cut groove 34 is provided, and the end of the roller shaft 31 is also formed by the semicircular spherical portion 35. Part is bearing hole 214It is easy to be inserted into.
[0038]
  On the other hand, each frame plate 131 has a fitting insertion hole 134 for supporting the roller shaft 31 (see FIG. 6). Each fitting hole 134 has a hole diameter dimension so that the bearing member 21 (the first bearing member 211 and the second bearing member 212) is fitted in a non-rotating state.In these insertion holes 134, the right side in FIG. 6 is the first hole according to the present invention, and the left side is the second hole according to the present invention.
[0039]
  The casing 40 is for supporting the feeding roller 50 and includes a top plate 41 and a pair of side plates 42 in the width direction formed by bending both side portions of the top plate 41 downward. Configured. The casing 40 is attached to the roller shaft 31 by passing the roller shaft body 32 through a pair of side plates 42. On each side plate 42, a cross shaft 43 for pivotally supporting the stopper 39 protrudes outward from the front side of the roller shaft main body 32 (the paper width setting member 141 side in FIG. 2).
[0040]
  Such a casing 40 has a feeding posture in which the end on the upstream side (right side in FIG. 2) from the roller shaft 31 is lowered and can feed the paper P, and the upstream end is on the upper side. The posture can be changed between the retracted posture and the retracted posture. The sheet is supplied onto the feeding tray 14 in a state where the casing 40 is set to the retracted position.
[0041]
  The stopper 39 is set so as to be rotatable around the cross shaft 43 in a state in which the casing 40 is set to the paper feeding posture, so that the paper P to be fed can be used like a warmth. On the other hand, in the state where the casing 40 is set to the retracted position, the protruding piece 391 protruding from the upper portion is provided on the back surface of the top plate 132 of the sheet feeding unit 13 and is not illustrated. It interferes with the convex part, and thereby the hanging posture is fixed.
[0042]
  The feeding roller 50 is held by a pair of stoppers 39 sandwiched between a pair of paper width setting members 141 while being placed on the feeding tray 14 and having a leading edge set in a hanging posture. The sheet P (see FIGS. 2 and 3) thus positioned is fed into the apparatus main body 11 one by one. As shown in FIG. 4, the roller shaft main body 32 is interposed between the side plates 42 of the casing 40. And a pickup roller 52 provided between the side plates 42 on the upstream side (the front side of the paper surface of FIG. 4) of the paper supply roller 51. The pickup roller 52 is rotatably supported around a pickup roller shaft 53 provided between the pair of side plates 42.
[0043]
  The pickup roller shaft 53 is arranged so that the peripheral surface of the pickup roller 52 contacts the uppermost one of the paper P in a state where the bundle of paper P placed on the feeding tray 14 is positioned by the stopper 39. The installation position is set, and the uppermost sheet P of the sheet bundle is taken out by the rotation of the pickup roller 52 and is directed to the sheet feeding roller 51. The paper P taken in by the pickup roller 52 is fed toward the apparatus main body 11 by the rotation of the paper feed roller 51 on the downstream side.
[0044]
  In the casing 40, a right side portion of the paper feed roller 51 shown in FIG. 4 is provided with a feed roller gear 54 that is integral with the roller shaft main body 32, and on the right side portion of the pickup roller 52. Is provided with a pickup roller shaft gear 55 rotatably supported around the pickup roller shaft 53. An intermediate gear 56 is interposed between the pickup roller shaft gear 55 and the paper feed roller gear 54, so that the paper feed roller 51 and the pickup roller 52 are in the same direction so as to draw the paper P (see FIG. 2 and clockwise in the example shown in FIG. 4.
[0045]
  A one-way clutch is interposed between the paper feed roller 51 and the paper feed roller gear 54 and between the pickup roller 52 and the pickup roller shaft gear 55, respectively. When the roller shaft gear 55 rotates in the direction in which the paper P is drawn (forward rotation), the paper feed roller 51 and the pickup roller 52 rotate together with the gears 54 and 55, respectively, while the gears 54 and 55 rotate in reverse. When doing so, the rollers 51 and 52 are prevented from rotating.
[0046]
  Incidentally, in the present embodiment, when a sheet drawn by the feeding roller 50 reaches a registration roller (not shown) at the rear of the sheet feeding unit 13, a predetermined sensor detects this, and this detection signal The registration roller is rotated forward by the reverse drive of the drive unit 60 based on the above, while the roller shaft 31 is rotated reversely. The one-way clutch is provided in order to avoid receiving a force in the direction in which the paper P once pulled in by the forward rotation of the feed roller 50 when the roller shaft 31 rotates reversely.
[0047]
  The drive unit 60 applies a rotational force to the roller shaft 31, and is fixed to the outer surface side of one frame plate 131 (the right side in FIG. 2 and the left side in FIG. 3). As shown in FIG. 4, the drive unit 60 includes a drive motor 62 fixed on the outer surface side with a support plate 61 interposed therebetween, and a gear group 63 attached on the inner surface side.
[0048]
  The gear group 63 includes a drive gear 631 that rotates integrally with the output shaft 621 of the drive motor 62, a first driven gear 632 that meshes with the drive gear 631, and a second driven that meshes with the first driven gear 632. A gear 633, a transmission gear 64 that meshes with the second driven gear 633 and transmits the rotational force to the roller shaft 31, and a first diameter that is larger than that of the first driven gear 632 that rotates concentrically with the first driven gear 632. A third driven gear 634 and a resist gear 65 meshed with the third driven gear 634 via a small gear (not shown). The registration gear 65 is concentrically connected to a registration roller (not shown) via a one-way clutch (not shown), and the rotation of the registration gear 65 is transmitted to the registration roller only when the drive motor 62 is reversely driven.
[0049]
  FIG. 5 is a perspective view showing an embodiment of the transmission gear 64. FIG. 5A is a state immediately before the flat key 33 of the roller shaft 31 is fitted into the oval hole 643 of the boss 642 of the transmission gear 64. (B) shows a state in which the flat key 33 is inserted into the oval hole 643. As shown in FIG. 5, the transmission gear 64 includes a transmission gear main body 641 meshing with the second driven gear 633, and a boss concentrically protruding from the transmission gear main body 641 to the inward side of the paper feeding unit 13. Part 642. An oval hole 643 having an oval cross-sectional shape that is set so that the flat key 33 of the roller shaft 31 is fitted in a close contact state is recessed in the end surface of the transmission shaft, and the oval key 63 is inserted into the oval hole 643. The roller shaft 31 is coupled to the transmission gear 64 so as to be integrally rotatable with the boss portion 642.
[0050]
  In the sheet feeding device 20 configured as described above, the present invention is configured such that the second bearing member 212 is externally fitted to the end of the roller shaft 31 on the hemispherical portion 35 side, and the second bearing in this state. After the member 212 is inserted into the insertion hole 134 of the left frame plate 131, the roller shaft 31 is once moved to the left and then moved to the right, and the flat key 33 is pivotally supported by the first bearing member 211. The roller shaft 31 is mounted on the drive unit 60 as shown in FIG. 4B by fitting into the oval hole 643 of the boss portion 642, and the roller is operated by performing the reverse operation to the above. The shaft 31 can be easily detached from the drive unit 60.
[0051]
  The operation of the present invention will be described below with reference to FIG. FIG. 6 is an explanatory diagram for explaining the operation of the present invention. FIG. 6A shows that the semicircular portion 35 of the roller shaft 31 is about to be loosely fitted into the fitting insertion hole 134 of the left frame plate 131. In the state (b), after the semicircular portion 35 of the roller shaft 31 is loosely fitted into the fitting hole 134, the second bearing member 212 is mounted in the fitting hole 134, and the flat key 33 is connected to the transmission gear 64. The state where the flat key 33 is inserted into the circular hole 213 of the boss 642, the state where the flat key 33 is opposed to the boss 642, and the stop ring 22 is mounted in the cut groove 34 of the roller shaft 31. Each state is shown.
[0052]
  When mounting the paper feeding unit 30 between the pair of frame plates 131 in the paper feeding unit 13, first, as shown in FIG. 6A, the second bearing member 212 is inserted into the groove 34 of the roller shaft 31. It is fitted on the side end (the end on the side where the cut groove 34 is provided). Subsequently, the roller shaft 31 is inclined, and the end of the roller shaft 31 on the cut groove 34 side is loosely fitted into the fitting hole 134. Then, with the flat key 33 of the roller shaft 31 no longer interfering with the right-side frame plate 131 in FIG. 6, the inclined roller shaft 31 is changed to a horizontal posture, and in this state (FIG. ) Is moved toward the left frame plate 131 and the second bearing member 212 is mounted in the fitting hole 134 of the left frame plate 131.
[0053]
  In this state, the flat key 33 is opposed to the oval hole 643 of the boss portion 642, and the roller shaft 31 is continuously moved toward the circular hole 213 as indicated by a right-pointing arrow in FIG. As a result, the flat key 33 of the roller shaft 31 is fitted into the oval hole 643 of the boss portion 642 as shown in FIG.
[0054]
  Next, the stop ring 22 is mounted in the cut groove 34 of the roller shaft 31 as indicated by an arrow in FIG. As a result, the leftward movement of the roller shaft 31 in FIG. 6 is blocked by the stop ring 22 as shown in FIG. 6 (d), whereby the sheet feeding unit 30 is prevented from coming off by a pair of frames. It is in a state of being installed between the plates 131.
[0055]
  In this way, when removing the paper feeding device 20 mounted on the paper feeding unit 13 of the copying machine 10, the reverse operation of the mounting operation may be performed.
[0056]
  As described in detail above, the paper feeding device 20 according to the present invention is suitable for application to the copying machine 10, for example, and is a paper positioned at the top of the paper bundle placed on the feeding tray 14. A roller shaft 31 having a paper feed roller 51 for sequentially feeding P is installed between a pair of frame plates 131, and a transmission gear 64 that rotates by driving of a drive motor 62 is concentrically connected to one end of the roller shaft 31. A boss portion 642 protrudes from the center position of the transmission gear 64, and the roller shaft 31 is detachable concentrically with respect to the small hole 643 of the boss portion 642 protruding from the boss portion 642. Since the flat key 33 to be inserted and the cut ring 34 in which the stop ring 22 formed at the end portion on the hemispherical portion 35 side is detachably mounted is provided, the stop ring 22 is Not installed The end of the roller shaft 31 on the hemispherical portion 35 side is loosely fitted into the fitting hole 134 of the frame plate 131 until the flat key 33 does not interfere with the transmission gear 64, and then the second bearing member 212 is fitted. After inserting the flat key 33 into the insertion hole 134 and subsequently inserting the flat key 33 into the oval hole 643 of the boss portion 642 of the transmission gear 64, the roller ring 31 is attached to the cut groove 34 of the roller shaft 31, thereby making the roller shaft 31 a pair of It can be mounted between the frame plates 131 in a retaining state.
[0057]
  When removing the roller shaft 31 once mounted between the frame plates 131, the stop ring 22 is removed from the roller shaft, and the roller shaft 31 is directed outward from the inside of the frame plate 131 on the hemispherical portion 35 side. When the flat key 33 of the roller shaft 31 is removed from the oval hole 643 of the boss 642 of the transmission gear 64, the roller shaft 31 is inclined so as not to interfere with the frame plate 131, and is pulled out in this state. Thus, the roller shaft 31 can be removed from between the pair of frame plates 131.
[0058]
  In the state where the roller shaft 31 is installed between the pair of frame plates 131, the roller shaft 31 rotates integrally with the transmission gear 64 because the flat key 33 inserted in the mounting hole rotates. The paper P is transmitted to the rotation of the paper feed roller 51 around the roller shaft 31 via the transmission gear 64 and the roller shaft 31, and the paper P stored in the paper storage section is fed.
[0059]
  Thus, since the rotation of the transmission gear 64 is directly transmitted to the roller shaft 31 without interposing an extra connecting member such as a conventional connecting cylinder between the roller gear 31 and the transmission gear 64, an upset occurs. In this state, the rotation of the transmission gear 64 is transmitted, and as a result, it is possible to effectively prevent the occurrence of inconveniences that cause the sheet feeding roller 51 to rotate eccentrically and interfere with sheet feeding.
[0060]
  In addition, it is not necessary to use a connecting member such as a conventional connecting cylinder or a biasing means such as a coil spring that applies a biasing force to the connecting member, which contributes to a reduction in the number of parts, and the roller shaft 31. The ease of attaching / detaching operation can be ensured.
[0061]
  The connecting structure according to the present invention includes a boss portion 642 projecting from the end face of the transmission gear 64, an oval hole 643 drilled in the boss portion 642, and a flat shape formed at the end portion of the roller shaft 31. Since it has a very simple structure with the key 33, it contributes to the reduction of parts cost and processing cost, and the roller shaft is inserted into and removed from the oblong hole 643 by an extremely simple operation. 31 can be attached to and detached from the transmission gear 64, and workability is improved.
[0062]
  In addition, since the cut groove 34 is provided in the peripheral surface of the end portion of the roller shaft 31 on the side to be inserted into the bearing hole 214 of the second bearing member 212, the stop ring 22 is fitted into the cut groove 34. The stop ring 22 is fitted into the cut groove 34 of the roller shaft 31 inserted through the second bearing member 212 to move in the direction in which the roller shaft 31 is pulled out (the stop ring 22 extends from the inside beyond the adjacent frame plate 131 to the outside). The movement of the roller shaft 31 can be reliably prevented from falling off.
[0063]
  Incidentally, when the erected roller shaft 31 is removed from between the pair of frame plates 131, the stop ring may be removed from the roller shaft 31. By doing so, the roller shaft 31 can be moved in the axial direction, so that the roller shaft 31 can be detached from the frame plate 131.
[0064]
  The present invention is not limited to the above embodiment, and includes the following contents.
[0065]
  (1) In the above embodiment, the stop ring 22 is fitted into the cut groove 34 provided in the roller shaft 31 to prevent the roller shaft 31 from coming off. A hole may be formed and a retaining pin may be inserted into the through hole.
[0066]
  (2) In the above embodiment, in order to rotate the roller shaft 31 integrally with the transmission gear 64, the flat key 33 having an oval shape in a sectional view is adopted at one end portion (insertion end portion) of the roller shaft 31. On the other hand, a boss portion 642 protrudes from the center position of the transmission gear 64, and a small hole 643 into which the flat key 33 is fitted is formed in the boss portion 642. In the present invention, the flat key 33 and the toner are provided. The storage space 643 is not limited to be set to an oval shape in cross-sectional view, and may be any shape as long as it can rotate integrally around the axis (for example, a polygonal column and a polygonal concave portion). It may be.
[0067]
  (3) In the above embodiment, the copying machine 10 is exemplified as the device to which the paper feeding device 20 is applied. However, in the present invention, the device to which the paper feeding device 20 is applied is the copying machine 10. However, the present invention is not limited to this, and may be applied to electronic devices such as facsimile machines and various printers.
[0068]
  (4) FIG. 7 is a cross-sectional view showing another embodiment of the coupling structure of the roller shaft and the transmission gear. (A) is the state where the coil spring is removed from the transmission gear, and (B) is the coil. A state in which the spring is inserted into the transmission gear, (c) shows a state in which the roller shaft is connected to the transmission gear via the coil spring.
[0069]
  In this embodiment, the flat key 33 as used in the previous embodiment is not formed at the end of the roller shaft 31, and if it is strong, it is concentric with the roller shaft main body 32 and has a cylindrical convex with the same diameter. A portion 36 (in this embodiment, the end of the roller shaft 31 itself) is formed. Incidentally, the columnar convex portion 36 does not need to have the same diameter as the roller shaft main body 32, and may have a smaller diameter than the roller shaft main body 32.
[0070]
  On the other hand, a circular recess 644 is formed in the end face of the boss 642 of the transmission gear 64. The inner diameter dimension of the circular concave portion 644 is set larger than the outer diameter dimension of the cylindrical convex portion 36, and thereby an annular gap is formed between the cylindrical convex portion 36 and the circular concave portion 644. I try to do it. A coil spring 66 dimensioned to correspond to this annular gap is mounted in advance in the circular recess 644 as shown in FIG. Incidentally, in the present embodiment, a coil spring 66 formed by processing a rectangular spring wire into a coil shape is adopted.
[0071]
  According to the connection structure of this embodiment, by rotating the transmission gear 64 in the direction in which the coil spring 66 is tightened, the columnar convex portion 36 on which the coil spring 66 is fitted is wound around the coil spring 66. Thus, the rotation of the transmission gear 64 is transmitted to the roller shaft 31. On the other hand, when the transmission gear 64 is rotated in a direction in which the coil spring 66 is rotated and loosened, the rotation of the transmission gear 64 is not transmitted to the cylindrical convex portion 36, so that the transmission gear 64 is rotated. Therefore, the roller shaft 31 does not rotate.
[0072]
  Thus, by interposing the coil spring 66 between the circular concave portion 644 and the columnar convex portion 36, the coil spring 66 functions as a one-way clutch, so that the roller shaft 31 moves in the feeding direction of the paper P. By adopting a coil spring 66 in the winding direction that can only be rotated, even if the transmission gear 64 rotates in the reverse direction, the roller shaft 31 does not rotate in the reverse direction, and the sheet is fed via the roller shaft 31. There is no inconvenience that the paper P is fed backward by the reverse rotation of the roller.
[0073]
【The invention's effect】
  According to the paper conveying apparatus of the present invention, the rotation of the transmission gear is directly transmitted without interposing various members having a complicated structure as conventionally provided between the roller shaft and the transmission gear. In addition, the rotation of the transmission gear is transmitted in a state where no misalignment occurs, and as a result, it is possible to effectively prevent the occurrence of inconvenience that the feeding roller rotates eccentrically and interferes with paper feeding.
[0074]
  In addition, since the structure is simplified compared to the conventional one, the number of parts can be reduced, and the ease of attaching and detaching the roller shaft can be ensured.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an embodiment of a copying machine to which a paper feeding device according to the present invention is applied.
FIG. 2 is a perspective view seen from the left side showing a sheet feeding unit in a state in which a top plate and a back plate are removed for explaining a mounted state of the sheet feeding device.
FIG. 3 is a perspective view seen from the left side showing a sheet feeding unit in a state in which a top plate and a back plate are removed for explaining a mounted state of the sheet feeding device.
FIGS. 4A and 4B are perspective views showing a paper feeding device mounted on a paper feeding unit, in which FIG. 4A shows a state where the paper feeding unit is removed from the drive unit, and FIG. 4B shows a paper feeding unit. Shows the state of being attached to the drive unit.
FIG. 5 is a perspective view showing an embodiment of a transmission gear, where (a) is a state immediately before the flat key of the roller shaft is fitted into the oval hole of the boss portion of the transmission gear, and (b) is a flat shape. Each of the keys is shown in a small hole.
6A and 6B are explanatory diagrams for explaining the operation of the present invention. FIG. 6A is a diagram showing a semicircular portion of a roller shaft that is about to be loosely fitted into a fitting hole of one (left side) frame plate. In the state (b), after the semicircular portion of the roller shaft is loosely fitted in the fitting insertion hole, the second bearing member is fitted in the fitting insertion hole, and the flat key 33 is fitted on the boss portion of the transmission gear. (C) is a state where the flat key is inserted into the circular hole of the first bearing member, and (d) is a state where the flat key is inserted into the circular hole of the first bearing member. ) Shows a state in which a stop ring is mounted in the cut groove of the roller shaft.
FIGS. 7A and 7B are cross-sectional views showing another embodiment of a coupling structure of a roller shaft and a transmission gear, where FIG. 7A is a state where a coil spring is removed from the transmission gear, and FIG. The state in which the bearing member is mounted in the insertion hole after the circular ball portion is loosely fitted in the insertion hole, and the flat key is opposed to the oblong hole of the transmission gear. Are respectively connected to the transmission gear.
FIGS. 8A and 8B are diagrams showing a conventional paper feeding device, where FIG. 8A is an explanatory view of a main part of the paper feeding device in a side view, FIG. 8B is an explanatory view of the front view, and FIG. FIG. 3 is an enlarged perspective view of a detachable structure.
[Explanation of symbols]
10 Copying machine (image forming device)
11 equipment body 12 lid
13 Paper Feeding Section 131 Frame Board
132 Top plate 133 Back plate
134 Insertion hole 14 Feed tray (paper storage part)
141 Paper width setting member 15 Paper output tray
20 Paper feeding device 21 Bearing member
211 First bearing member 212 Second bearing member
213 Circular hole 214 Bearing hole
22 Stop ring
30 Paper feeding unit 31 Roller shaft
32 Roller shaft body 33 Flat key
34 Cut groove (attached part) 35 Semi-spherical part
39 Stopper 391 Projection
40 Casing 41 Top plate
42 Side plate 43 Cross shaft
50 Feed roller 51 Feed roller
52 Pickup roller 53 Pickup roller shaft
54 Feed roller gear 55 Pickup roller shaft gear
60 drive unit 61 support plate
62 Drive motor 63 Gear group
631 Drive gear 632 First driven gear
633 2nd driven gear 634 3rd driven gear
64 Transmission gear 641 Transmission gear body
642 Boss part P Paper

Claims (3)

First and second frames disposed opposite to each other; a roller shaft having a length spanned between the first and second frames, and having a first end and a second end at both ends; A paper transporting device provided with a feeding roller attached to the roller shaft and sequentially feeding the paper located at the top of the paper bundle, and a transmission gear arranged on the first frame side ,
A boss portion projects from the center position of the transmission gear, and a bearing insertion hole into which the first end portion of the roller shaft is removably inserted is formed in the boss portion. A mechanism for transmitting torque of the transmission gear to the roller shaft;
The first frame includes a first hole into which the boss portion is inserted, and a first bearing member that receives the boss portion is attached to the first hole,
The second frame includes a second hole into which the second end portion of the roller shaft is fitted, and a second bearing member that receives the second end portion of the roller shaft is detachable in the second hole. Attached,
The second end portion of the roller shaft is a semispherical sphere, and the second bearing member is freely fitted from the second end portion side of the roller shaft,
The second hole, in a state where the boss portion in the first hole is inserted, wherein the roller shaft first, that having a size to allow placing split by diagonally between the second frame A sheet conveying apparatus characterized by the above. On the side of the second end portion of said roller shaft, retaining structure detachable for preventing the movement is provided the roller axis direction escaping outward from the second hole of the second frame The sheet conveying apparatus according to claim 1. The retaining structure includes a cut groove formed in a peripheral surface on the second end portion side of the roller shaft, and a stop ring that is detachably attached to the cut groove. The sheet conveying apparatus according to claim 1 or 2.

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