JP2005126213A - Paper feeding unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a paper feeding unit capable of facilitating maintenance. <P>SOLUTION: This paper feeding unit 2 is provided with a plastic housing lower 4 and a plastic housing upper 6 detachably fitted to the housing lower 4. An upper housing 6 is positioned at an insertion position by inserting and passing a pair of flat outer surfaces 30, 32 in each of shaft parts 22, 24 of the housing upper 6 into a cutout 20 of a corresponding bearing portion 14 of the housing lower 4 from above. The housing upper 6 is rotated in one rotation direction until a closed position at least a partial circumferential area of each circular arc-shaped outer surface 26, 28 of the shaft parts 22, 24 comes into contact with a bearing surface 18, whereby the housing upper 6 is fitted to the housing lower 4. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a paper feeding unit applied to an image forming apparatus such as an electrostatic copying machine, a laser printer, or a facsimile.

An image forming apparatus, for example, a copying machine main body in an electrostatic copying machine is generally provided with a paper storage container such as a paper feeding cassette and a paper feeding deck. The copying machine main body also includes a pickup roller for sending out the paper stored in the paper storage container, a pair of paper feed rollers for carrying the paper fed by the pickup roller one by one, and the paper carried by the paper feed roller. A pair of conveying rollers for conveying toward the registration rollers is provided. Among these, a so-called paper feed unit in which a pickup roller and a pair of paper feed rollers are unitized is already known.

One example of the above-described sheet feeding unit is an upper holding that extends in the axial direction on the sheet feeding roller disposed on the upper side of the pair of sheet feeding rollers and holds both ends of the pickup roller and the sheet feeding roller. A member, a lower holding member that extends in the axial direction below the paper feed roller (the rolling roller) disposed on the lower side of the paper feed roller pair, and holds both ends of the paper feed roller, an upper holding member, And a connecting member that integrally connects both end surfaces of the lower holding member in the longitudinal direction. The upper holding member and the lower holding member are formed from a metal member, and the connecting member is formed from a metal plate member. Each of the connecting members is fastened with a plurality of screws to both longitudinal end faces of the upper holding member and the lower holding member. Each of the connecting members is formed with a bent piece, and each of the bent pieces of the connecting member is fastened to the copying machine main body with a plurality of screws, whereby the paper feeding unit is detachably attached to the copying machine main body ( Patent Document 1).

Since the paper feed unit is composed of a pickup roller and a pair of paper feed rollers as a unit, maintenance can be performed with the paper feed unit removed from the copier body, so the roller is mounted on the copier body. Maintenance is easier compared to what has been done. However, the sheet feeding unit is configured by fastening each of the connecting members to the longitudinal end surfaces of the upper holding member and the lower holding member with a plurality of screws. And maintenance such as repair and replacement is troublesome. Also, when performing maintenance such as repair or replacement on the paper feed roller and / or under the paper feed roller after the paper feed unit is removed from the copier body, one of the connecting members is fastened with a plurality of screws. Since it must be released and removed from the longitudinal end surfaces of the upper holding member and the lower holding member, maintenance such as repair and replacement is very difficult. Moreover, since many screws are required, the cost increases.

On the other hand, a copying machine provided with a paper feeding unit integrally formed with a synthetic resin on the top and bottom of the housing has already been developed and put into practical use by the applicant, Kyocera Mita Corporation (product name of the copying machine: Eagle, Pegasus, etc.). However, even in this paper feeding unit, the above-mentioned problem has not been solved because the upper and lower housings are fastened with screws. Furthermore, the upper part of the paper feed roller is mounted on the housing, and the lower part of the paper feed roller is attached to the lower part of the housing. When replacing them during maintenance, the driven shaft must be removed, which makes the replacement work very difficult. there were.

Japanese Patent Laid-Open No. 2003-165543

An object of the present invention is to provide a novel paper feeding unit that enables easy assembly, disassembly and maintenance as a whole.

Another object of the present invention is to provide a novel paper feeding unit that enables easy maintenance on and / or under the paper feeding roller.

Still another object of the present invention is to provide a novel paper feeding unit that reduces the number of screws and enables cost reduction.

According to one aspect of the present invention, in a sheet feeding unit including a synthetic resin housing under and a synthetic resin housing that is detachably attached to the housing under, the housing under is on both sides in the longitudinal direction. Bearing portions formed on a pair of side walls disposed in each portion, each of the bearing portions being disposed on a common axis and having an arc-shaped bearing surface longer than a semicircle and an inner diameter of the bearing surface And a notch formed of a pair of opposed surfaces connected to the upper end of the side wall and extending linearly upward from both ends of the bearing surface in parallel and arranged on a common axis Each having a shaft portion extending outward from a pair of side walls disposed on both sides in the longitudinal direction, each of the shaft portions being disposed in a pair of symmetrical positions in the radial direction across the shaft center. On the outer surface of the circular arc and another symmetrical position in the radial direction across the axis And a pair of flat outer surfaces extending parallel to each other between both ends of the arcuate outer surface, and the pair of flat outer surfaces in each of the shaft portions on the housing are connected to the corresponding bearing portions below the housing. By inserting into the notch from above and substantially passing it, one of the arcuate outer surfaces comes into contact with and is received by the bearing surface, and the housing is positioned at the insertion position. The upper surface of the housing is mounted under the housing by rotating in one rotational direction to a closed position where at least a partial region in the circumferential direction of both of the arc-shaped outer surfaces contacts the bearing surface. A paper unit is provided.
One side wall disposed on one side in the longitudinal direction on the housing is a sliding protrusion that protrudes outward from the one side wall toward the one side wall in the lower surface direction on the housing. A sliding protrusion having an inclined surface that is inclined in the axial direction of the shaft portion, and a positioning protrusion that extends outward in the width direction from the one end portion in the width direction of the housing and outward in the radial direction with respect to the shaft portion; A partial region of the inner corner at the upper end of one side wall under the housing is positioned so as to exist on a rotation trajectory in one rotation direction of the inclined surface of the sliding projection, and one side region under the housing In addition, a movement-preventing wall that prevents the positioning protrusion from moving in the other rotation direction is disposed at the inner position with the space portion on one side wall under the housing, and the upper portion of the housing is inserted. Positioned in position In this state, the positioning protrusion on the housing is positioned so as to be rotatable in one rotation direction in the space under the housing, and the housing is rotated in one rotation direction from the insertion position toward the closed position. Then, the inclined surface of the sliding projection on the housing is brought into contact with a partial area of the inner corner at the upper end of one side wall under the housing and is moved relative to the inner side in the axial direction. Each of the upper shafts is slid in the axial direction from one of the longitudinal directions on the housing to the corresponding bearing surface, and the entire housing is slid in the same direction to the closed position. Due to the sliding movement on the housing, the movement-preventing wall surface under the housing is relatively positioned on the rotation trajectory of the positioning protrusion on the housing in the other rotation direction. When the housing is rotated from the closed position to the open position in the other rotation direction, the positioning protrusion on the housing is brought into contact with the movement-preventing wall surface under the housing, and the other rotation is performed. It is preferable that movement in the moving direction is prevented and the housing is positioned in the open position.
The rotation angle in the other rotation direction from the closed position to the open position on the housing is preferably smaller than the rotation angle in the other rotation direction from the closed position to the insertion position.
It is preferable that a locking means is disposed between the housing and the housing under the housing so as to releasably lock the housing with respect to the housing under the closed position.
According to another aspect of the present invention, a synthetic resin housing is provided under a synthetic resin housing, and a synthetic resin housing mounted so as to be rotatable and detachable between an open position and a closed position with respect to the housing. In the paper feed unit provided, the lower part of the paper feed roller is rotatably and detachably disposed at the central part in the longitudinal direction below the housing, and the subunit is detachable at the central part in the longitudinal direction on the housing. A sub-unit is mounted with a paper feed roller and a pick-up roller that are rotatably connected to each other. A driven shaft rotates on one side of the housing in the longitudinal direction with the sub-unit as a boundary. The drive source is arranged under the housing, and when the subunit is mounted on the housing, the feed roller and the driven shaft are releasably connected so that the housing is in the open position. When being rotated to the closed position, the paper feed roller on the housing is pressed against the paper feed roller below the housing and the driven shaft is releasably connected to the drive source. A paper unit is provided.
A pair of support walls are disposed in the longitudinal center portion below the housing at intervals in the longitudinal direction, and a bearing portion having an open upper end is disposed at each upper end portion of the support walls. The lower roller includes a shaft and a roller rotatably supported by the shaft, and both end portions of the shaft are mounted so as not to rotate relative to the bearing portions of the corresponding support wall and to be detachable. preferable.
Each of the bearing portions in each of the support walls has a pair of side walls facing each other in parallel to the plane across an imaginary plane passing through the axis and extending in the vertical direction, and an intermediate region between one side wall and a lower end of the other side wall. A bottom wall extending in a circular arc shape toward the top, and a protrusion extending inward is formed at the upper end of one side wall, and both end portions of the shaft below the feed roller have an arc-shaped outer peripheral surface, a shaft A flat surface extending in the axial direction approaching each other from the tip of the shaft, and the flat surface at both ends of the shaft is pressed against the other side wall of the corresponding support wall under the feed roller and both ends of the shaft It is preferable that the arc-shaped outer peripheral surface of the portion is held in pressure contact with the side wall and the bottom wall of the corresponding support wall, overcoming the protrusion on one side wall of the corresponding support wall.
A pair of support walls are disposed at a longitudinally central portion on the lower surface side of the housing, and are spaced apart in the longitudinal direction. When the driven shaft is rotatably supported, the subunit is detachably mounted between the pair of support walls, and the subunit is mounted between the pair of support walls, the sub-unit feed roller is placed on the driven roller. It is preferable that the drive shaft is releasably connected to one end of the drive shaft.
Each of the support walls is formed with a bearing portion and a retaining portion. Each of the bearing portions includes a semicircular bearing surface disposed on the same axis as the driven shaft, and an upper side from both ends of the bearing surface. And a notch formed of a pair of opposed surfaces connected to the upper end of the support wall, and each retaining portion is disposed inside the support wall with the bearing portion sandwiched in the width direction on the housing. The arcuate surfaces concentric with the axis formed on the mutually opposing surfaces of the pair of retaining protrusions, and having a width smaller than the inner diameter of each of the arcuate surfaces and from the upper end of each of the arcuate surfaces A pair of opposing surfaces extending in a straight line parallel to the upper side and connected to the upper end of the support wall, the subunit has a pair of side walls, and each of the side walls has an annular stopper portion Each of the parts to be removed is sandwiched between a through hole having a common axis and an axial center. A pair of arcuate outer surfaces arranged at symmetric positions in the radial direction and a pair of arcuate outer surfaces arranged at other symmetric positions in the radial direction across the axis and extending in parallel between both ends of the arcuate outer surface A flat outer surface, a shaft on the paper feed roller, and a roller integrally disposed on the shaft. Both ends of the shaft on the paper feed roller are through-holes in the part to be removed via a bearing member. Each of the bearing members includes a cylindrical portion and an annular flange extending radially outward from an outer peripheral surface at one end in the axial direction of the cylindrical portion. The inner peripheral surface of the cylindrical portion is fitted into the outer peripheral surface of the end portion of the shaft so as to be relatively rotatable, and corresponds to each axially outer surface of the to-be-prevented portion. An annular gap is formed between the annular flange of the bearing member and the inner surface facing the outer surface in the axial direction. A partial area in the axial direction on the outer peripheral surface of the cylindrical portion is exposed to the outside, and a pair of flat outer surfaces in each of the to-be-prevented portions of the subunits are substantially inserted into the notches in the corresponding retaining portions on the housing. And the sub-unit is positioned at the insertion position by the partial region of each cylindrical portion of the bearing member being supported on the circular arc surface through the notch of the corresponding bearing portion on the housing, Subsequently, it is preferable that the subunit is mounted on the housing by rotating the subunit to a closed position where each arc-shaped outer surface of the to-be-prevented portion contacts the arc surface of the corresponding retaining portion.
It is preferable that a locking means is provided between the subunit and the housing so as to releasably lock the subunit in the closed position with respect to the housing.
One end of the shaft on the paper feed roller disposed in the subunit includes a semicircular outer peripheral surface and a flat surface extending from one end of the shaft to the other end along the shaft center. One end of the driven shaft that is rotatably supported by the shaft includes a semicircular outer peripheral surface and a flat surface extending from one end of the shaft to the other end along the shaft center. By attaching the subunit to the pair of support walls so that the flat surface at one end of the shaft is opposed to the flat surface at one end of the driven shaft, It is preferable that the one end portion of the driven shaft is releasably driven and connected.
The drive source under the housing is an electric motor, the drive gear is integrally disposed on the drive shaft of the electric motor, and the driven gear is integrally disposed on the other end of the driven shaft on the housing, When the upper side of the housing is positioned at the closed position relative to the lower side of the housing, it is preferable that the driven gear of the driven shaft is releasably connected to the driving gear of the electric motor.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, a preferred embodiment of a paper feeding unit configured according to the invention will be described in detail with reference to the accompanying drawings. 1 to 29, substantially the same parts are denoted by the same reference numerals.

Referring to FIGS. 1 to 3 and FIG. 18, the paper feeding unit 2 is mounted with a synthetic resin lower housing 4, and is rotatable and detachable between an open position and a closed position with respect to the lower housing 4. And a housing 6 made of synthetic resin. The direction and position of the lower housing 4 and the upper housing 6 will be described with reference to FIG. 1. The longitudinal direction of the lower housing 4 and the upper housing 6 indicates the left-right direction, and one side of the longitudinal direction is the right side. The other side portion in the longitudinal direction indicates the left side portion, the width direction indicates the up-down direction, and the width. One end portion in the direction indicates a lower end portion, and the other end portion in the width direction indicates an upper end portion. Needless to say, this is the case in other figures.

The other side portion of the lower housing 4 that is elongated as a whole protrudes outward in the width direction from one end portion in the width direction, and thus is formed wider than the width of one side portion. Two locking pins 8 extending in the direction from the other side in the longitudinal direction to the one side and the extending direction thereof are respectively arranged on the protruding region on the other side of the lower side 4 of the housing and on one side end. Yes. An electric motor M as a drive source is attached to the outside of one side of the lower housing 4. The paper feeding unit 2 is inserted from the front side to the rear side of the housing recess provided in the main body of the image forming apparatus (not shown), and the locking pin 8 is inserted into the locking hole (not shown) provided in the main body. Each is detachably fitted to the apparatus main body.

Referring to FIGS. 18, 19, and 20, a pair of side walls 10 and 12 are disposed on both sides in the longitudinal direction of the lower housing 4. Bearing portions 14 and 16 are formed on the side walls 10 and 12 at one end in the width direction of the lower housing 4, respectively. Each of the bearing portions 14 and 16 having substantially the same shape and size as each other includes an arc-shaped bearing surface 18 which is disposed on a common axis and is longer than a semicircle, and is smaller than the inner diameter of the bearing surface 18. From a pair of opposing surfaces 20a having a width and extending linearly in parallel from the two upper ends of the bearing surface 18, that is, the upper ends of the bearing surface 18 opened upward, and connected to the upper ends of the side walls 10 and 12 And a notch 20. As can be easily understood from FIG. 20, when the bearing surface 18 is viewed in the axial direction, a pair of opposed surfaces (wall surfaces) 20 a of the notch 20 passes through the axis of the bearing surface 18 and extends in the vertical direction. It exists in the symmetrical position on both sides of a plane (not shown), and is formed so as to extend in parallel to the virtual plane. As apparent from the above description, it can be said that the bearing surfaces 18 of the bearing portions 14 and 16 are opened upward through the notches 20.

A pair of side walls 6 </ b> A and 6 </ b> B are disposed on both sides in the longitudinal direction of the upper housing 6. The side walls 6A and 6B at one end in the width direction of the housing top 6 are provided with shaft portions 22 and 24 arranged on a common axis and extending outward from the side walls 6A and 6B of the housing top 6, respectively. Yes. Each of the shaft portions 22 and 24 having substantially the same shape and size as each other has a pair of arcuate outer surfaces 26 and 28 disposed at symmetrical positions in the radial direction across the shaft center, and the shaft center between the shaft portions 22 and 24. A pair of flat outer surfaces 30 and 32 are disposed at other symmetrical positions in the radial direction and extend parallel to each other between both ends of the arc-shaped outer surfaces 26 and 28. The arc-shaped outer surfaces 26 and 28 are symmetrical with respect to each other with respect to the axial center, and the flat outer surfaces 30 and 32 are also symmetrical with respect to each other with respect to the axial center.

By inserting a pair of flat outer surfaces 30 and 32 in each of the shaft portions 22 and 24 of the upper housing 6 into the notches 20 of the corresponding bearing portions 14 and 16 of the lower housing 4 from above and substantially passing through. One of the arcuate outer surfaces 28 located on the lower side contacts and is received by the bearing surface 18 so that the upper housing 6 is positioned at the insertion position (see FIG. 21). When viewed from one side in the longitudinal direction to the other side, the upper housing 6 is inclined obliquely to the upper left in FIG. Subsequently, the upper housing 6 is rotated in one rotation direction (clockwise in FIG. 21) toward the closed position. FIG. 22 shows a state in which it is rotated by a slight angle in one rotation direction from the insertion position toward the closing position. This position indicates an open position on the housing 6 which will be described later.

The upper housing 6 is rotated in one rotational direction until a closed position (see FIG. 23) where at least a partial region in the circumferential direction of both the arc-shaped outer surfaces 26 and 28 of the shaft portions 22 and 24 contacts the bearing surface 18. By rotating, the upper housing 6 is attached to the lower housing 4 in a substantially superposed state from above. In a state where the housing top 6 is positioned at the closed position, at least a partial region in the circumferential direction of both the arc-shaped outer surfaces 26 and 28 of the shaft portions 22 and 24 is positioned so as to contact the bearing surface 18. Each of the portions 22 and 24 is reliably prevented from coming out radially outward with respect to the bearing portions 14 and 16. As clearly shown in FIG. 23, in the embodiment, in the state where the upper housing 6 is positioned at the closed position, the entire circumferential region of the arc-shaped outer surface 26 of each of the shaft portions 22 and 24 is the bearing surface 18. Further, a partial region in the circumferential direction of the arc-shaped outer surface 28 is positioned so as to be brought into contact with the bearing surface 18. With the housing top 6 positioned in the closed position, the side walls 6 A and 6 B of the housing top 6 are positioned inside the corresponding side walls 10 and 12 of the housing bottom 4.

Referring to FIGS. 20, 24 and 25, one side wall 6A of the upper housing 6 is provided with a sliding projection 34 disposed so as to protrude outward from the one side wall 6A with a certain thickness. The sliding projection 34 has an inclined surface 34a that is inclined in the axial direction of the shaft portion 22 toward the one side wall 6A in the direction of the lower surface of the upper housing 6 (the lower surface facing the upper surface of the lower housing 4 in the closed position). Is arranged. The sliding projection 34 has a predetermined thickness in the width direction of the upper portion 6 of the housing, and is disposed at a position near the other end side in the width direction with respect to the shaft portion 22. On the upper surface side of the upper housing 6 with respect to one end of the inclined surface 34a of the slide projection 34, another projection 35 is formed continuously to the one end. The side surfaces of the other protrusions 35 (side surfaces facing the longitudinal direction of the housing 6) are flat surfaces extending in a direction perpendicular to the axis of the shaft portion 22. A partial region of the inner corner portion 10a at the upper end portion of one side wall 10 of the lower housing 4 is positioned so as to exist on the rotation trajectory in the one rotation direction of the inclined surface 34a of the sliding projection 34. Yes.

Referring to FIGS. 20 and 26, a positioning protrusion 36 is formed on one side of the housing 6 so as to extend radially outward with respect to the shaft 22. The positioning protrusion 36 is formed so as to extend outward from one end in the width direction of the upper housing 6. The positioning protrusion 36 has a predetermined thickness in the upper and lower surface directions of the upper housing 6, has a predetermined width in the axial direction of the shaft portion 22, and one end of the housing upper 6 in the width direction with respect to the shaft portion 22. Arranged on the side. Positioning is in one side region of the lower housing 4 and at an inner position (a position closer to the other side of the lower housing 4) with the space 38 sandwiched (sandwiched) with respect to one side wall 10 of the lower housing 4. A movement prevention wall surface 40 is provided for preventing movement of the projection 36 in the other rotation direction (counterclockwise in FIG. 22).

Referring to FIGS. 21 and 26, in a state where the upper housing 6 is positioned at the insertion position, the positioning protrusion 36 on the upper housing 6 rotates in one rotational direction within the space 38 in the lower housing 4. Positioned as possible. When the upper housing 6 is rotated in one rotational direction from the insertion position (see FIG. 21) to the closed position (see FIG. 23), the inclined surface 34a of the sliding projection 34 on the upper housing 6 is moved below the housing. 4 is brought into contact with a partial region of the inner corner 10a at the upper end of one of the side walls 10 and is relatively moved so as to be relatively moved inward in the axial direction of the shaft 22 (see FIGS. 24 and 25). As a result, each of the shaft portions 22 and 24 of the upper housing 6 corresponds to the corresponding bearing surface 18 from one side to the other in the longitudinal direction of the lower housing 4 and the upper housing 6 (one of the lower housing 4 and the upper housing 6). It is slid in the axial direction (from the side toward the other side) and the entire upper housing 6 is slid in that direction and positioned in the closed position (see FIGS. 23 and 28). . As shown in FIG. 28, due to the sliding movement of the upper housing 6, the movement preventing wall surface 40 of the lower housing 4 rotates in the other rotational direction of the positioning projection 36 of the upper housing 6. It is relatively positioned on the movement locus (because the position of the rotation locus of the positioning projection 36 on the housing 6 is moved from the region where the space portion 38 is present to the region where the movement blocking wall surface 40 is present).

22, 23, 28, and 29, when the upper housing 6 is rotated in the other rotation direction from the closed position (see FIG. 23) to the open position (see FIG. 22), The positioning projection 36 on the upper housing 6 is brought into contact with the movement-preventing wall surface 40 on the lower housing 4 to prevent movement in the other rotational direction, so that the upper housing 6 is positioned in the open position (see FIG. 29). ). As can be easily understood from FIGS. 21 to 23, the rotation angle of the housing 6 on the other rotation direction from the closed position (see FIG. 23) to the open position (see FIG. 22) is the closed position. It is defined to be smaller than the rotation angle in the other rotation direction from the insertion position (see FIG. 21) to the insertion position (see FIG. 21). As a result, since at least a partial region in the circumferential direction of both the arc-shaped outer surfaces 26 and 28 of each of the shaft portions 22 and 24 is positioned so as to contact the bearing surface 18, the bearing portions of each of the shaft portions 22 and 24 are arranged. With respect to 14 and 16, it is possible to reliably prevent the radially outward disengagement (the disengagement through the notch 20), so that maintenance can be performed easily and reliably.

When it is desired to prevent the housing top 6 from moving to the right in FIG. 29 in a state where the housing top 6 is positioned at the open position as shown in FIG. 29, the shaft located above the space portion 38. It is preferable that a synthetic resin band (not shown) is wound around the portion 22 so as to be released. Although not shown in FIGS. 20 to 23 and the like, a notch 42 extending from one end in the axial direction to the other end direction is formed in the shaft portion 22 (see FIG. 29). A plurality of electric wires (not shown) are passed. Accordingly, the band has a function of bundling electric wires and a function of preventing movement of the upper housing 6 positioned at the open position. Such a configuration enables the maintenance to be performed more stably because the upper housing 6 is stably positioned in the open position.

When the housing top 6 is removed from the housing 4, the housing top 6 is rotated from the closed position to the open position, and then the housing top 6 is moved to the other longitudinal direction. As a result, the position of the rotation locus of the positioning projection 36 on the housing 6 is moved from the region where the movement preventing wall surface 40 is present to the region where the space 38 is present, so that the housing top 6 is inserted from the open position. It can be rotated to a position. Subsequently, by moving the upper housing 6 upward with respect to the housing 4, the shaft portions 22 and 24 can be pulled out through the notches 20 of the corresponding bearing portions 14 and 16. It can be easily removed.

In addition, between the upper housing 6 and the lower housing 4, there is provided locking means for releasably locking the upper housing 6 with respect to the lower housing 4 in the closed position. As shown in FIG. 4, the locking means includes a locking pin portion 44 extending upward from the upper surface on the other end side in the width direction of the lower housing 4 on each side wall portion of the lower housing 4, 6 and the locking holes 46 provided in the overhanging portions 6a and 6b provided so as to extend outwardly from the both side walls 6A and 6B, respectively. As described above, when the upper housing 6 is rotated from the open position to the closed position with respect to the lower housing 4, each of the locking holes 46 of the upper housing 6 is connected to the corresponding locking pin 44 of the lower housing 4. Press-fitted, the upper housing 6 is locked in a closed position relative to the lower housing 4 (see FIGS. 1 to 3).

According to the paper feeding unit 2 according to the present invention, the upper housing 6 can be attached to the lower housing 4 in an extremely easy and reliable manner, and can be removed very easily. Assembly, disassembly and maintenance with the lower housing 4 can be easily performed. Further, since the number of screws can be reduced as compared with the conventional paper feeding unit, the cost can be reduced.

Referring to FIG. 4, a paper feed roller lower 50 is rotatably and detachably disposed at the longitudinal center of the housing lower 4. A subunit 52 is detachably mounted at the longitudinal center of the upper housing 6. The sub-unit 52 is mounted with a paper feed roller upper 54 and a pickup roller 56 that are rotatably and detachably driven. A driven shaft 58 is rotatably supported via a bearing (not shown) on one side region (left side region in FIG. 4) in the longitudinal direction with the subunit 52 as a boundary on the top 6 of the housing. When the sub unit 52 is mounted on the housing 6, the paper feed roller 54 and the driven shaft 58 are drivingly connected so as to be releasable. Further, when the upper housing 6 is rotated from the open position to the closed position, the upper feed roller 54 on the upper housing 6 is brought into pressure contact with the lower feed roller 50 on the lower housing 4 and the driven shaft 58 serves as a drive source. Removably connected to the drive.

Referring to FIGS. 15 to 17, a pair of support walls 62 are arranged at a distance in the longitudinal direction at a central portion in the longitudinal direction on the upper surface side of the bottom wall of the lower housing 4. A bearing portion 64 having an open upper end is disposed at each upper end portion of the support walls 62 having substantially the same shape and size. The lower feed roller 50 includes a shaft 50A, a roller 50B rotatably supported by the shaft 50A, a torque limiter 50C disposed between the roller 50B and the shaft 50A, and both ends of the shaft 50A. However, it is attached to the bearing portion 64 of the corresponding support wall 62 so that it cannot rotate relative to the bearing portion 64 and is detachable.

More specifically, as shown in FIG. 17, each of the bearing portions 64 in each of the support walls 62 is mutually connected with a virtual plane (not shown) extending in the vertical direction passing through the axis. And a bottom wall 70 extending in an arc shape from an intermediate region of one side wall 66 toward the lower end of the other side wall 68. A protrusion 72 extending inward is formed at the upper end of one side wall 66. In this embodiment, each of the support walls 62 is formed integrally with the lower housing 4, but is formed of a synthetic resin that is separate from the lower housing 4, and is formed at the bottom in the center in the longitudinal direction of the lower housing 4. There are other embodiments that are secured to the wall by any suitable means.

Both ends of the shaft 50A under the paper feed roller 50 are provided with an arcuate outer peripheral surface 50a and flat surfaces 50b extending in the axial direction approaching each other from both ends of the shaft 50A. Under the feed roller 50, the flat surfaces 50b at both ends of the shaft 50A are brought into pressure contact with the other side wall 68 of the corresponding support wall 62, and the arcuate outer peripheral surfaces 50a at both ends of the shaft 50A correspond to the corresponding support. The protrusion 62 of one side wall 66 of the wall 62 is moved down and substantially held in pressure contact with the one side wall 66 and the bottom wall 70. When the lower sheet feeding roller 50 is removed, the lower sheet feeding roller 50 can be pulled out from the upper end through the side walls 66 and 68 by lifting the lower sheet feeding roller 50 with respect to each of the support walls 62. As described above, the lower feed roller 50 is detachably attached to the lower housing 4 with almost one touch, so that maintenance such as repair and replacement can be performed easily and quickly, and is extremely useful in practice. . In addition, since no screws are used, the cost can be reduced.

With reference to FIGS. 4, 7, and 12, a pair of support walls 74 are disposed in the center portion in the longitudinal direction on the lower surface side of the upper housing 6 with an interval in the longitudinal direction. A driven shaft 58 extends in the longitudinal direction and is rotatably supported on one side region (region on the side wall 6A side) in the longitudinal direction with the pair of support walls 74 as a boundary on the housing 6. . The subunit 52 is detachably mounted between the pair of support walls 74. When the sub unit 52 is mounted between the pair of support walls 74, the upper paper feed roller 54 of the subunit is drivingly connected to one end of the driven shaft 58 so as to be releasable.

More specifically, a bearing portion 76 and a retaining portion 77 are formed on each support wall 74. Each of the bearing portions 76 having substantially the same shape and size as each other includes a semicircular bearing surface 76A disposed on a common axis with the driven shaft 58, and both ends (upper ends) of the bearing surface 76A. A notch 76 </ b> B including a pair of facing surfaces 76 a extending upward and connected to the upper end of the support wall 74 is provided. The distance between the pair of opposed surfaces 76a forming the notch 76B, particularly the distance in the region near both ends of the bearing surface 76A, is formed to be substantially the same as the diameter of the bearing surface 76A. The diameter may be larger than the diameter of the bearing surface 76A. A pair of opposing surfaces (wall surfaces) 76a of the notch 76B when each of the bearing surfaces 76A is viewed in the axial direction, and the pair of opposing surfaces 76a in the region near both ends of the bearing surface 76A is the axis of the bearing surface 76B. It exists in a symmetrical position across a virtual plane (not shown) extending in the vertical direction, and is formed to extend in parallel to the virtual plane. As apparent from the above description, it can be said that the bearing surface 76A of the bearing portion 76 in each of the support walls 74 is opened upward via the notch 76B.

Each of the retaining portions 77 is formed on the mutually opposing surfaces of a pair of retaining projections 78 disposed on the inner side of each of the support walls 74 with the bearing portion 76A sandwiched in the width direction of the upper housing 6. A circular arc surface 78A concentric with the axis common to the driven shaft 58 and a width smaller than the inner diameter of each circular arc surface 78A and extending linearly upward in parallel from the upper end of each circular arc surface 78A. 74 and a notch 80 having a pair of opposed surfaces 80a connected to the upper end of 74. When each arc surface 78A is viewed in the axial direction, a pair of opposed surfaces (wall surfaces) 80a of the notch 80 sandwich a virtual plane (not shown) extending in the vertical direction through the axis of each arc surface 78A. However, they are formed so as to exist at symmetrical positions and to extend in parallel to the virtual plane. Each of the retaining protrusions 78 is symmetrical with respect to the virtual plane. The radius of each arc surface 78A is larger than the radius of the corresponding bearing surface 76A.

8 to 13, the subunit 52 includes a vertically long housing 81, and the housing 81 includes sidewalls 82 on both sides in the width direction (substantially the left and right direction in FIGS. 8 to 10). Each of the side walls 82 at one end portion in the longitudinal direction of the housing 81 (the lower end portion in the vertical direction in FIGS. 8 to 10) is provided with an annular stopper portion 84 protruding outward. Each of the to-be-removed portions 84 has a through-hole 84a (see FIG. 8) having a common axis, a pair of arcuate outer surfaces 84b disposed at symmetrical positions in the radial direction across the axis, and the axis. And a pair of flat outer surfaces 84c which are arranged at other symmetrical positions in the radial direction and extend in parallel with each other between both ends of the arc-shaped outer surface 84b. The pair of flat outer surfaces 84 c are positioned so as to extend in the longitudinal direction of the housing 81 in the tangential direction of the stopper portion 84. Each of the arcuate outer surfaces 84b is symmetrical with respect to the axis, and each of the flat outer surfaces 84c is also symmetrical with respect to the axis.

The upper sheet feed roller 54 includes a shaft 88 and a roller 90 disposed integrally with the shaft 88. Both end portions of the shaft 88 of the upper sheet feed roller 54 are rotatably supported in the through holes 84 a of the to-be-removed portions 84 via bearing members 92. Each of the bearing members 92 includes a cylindrical portion 92a and an annular flange 92b that extends radially outward from one axial outer peripheral surface of the cylindrical portion 92a. In each of the bearing members 92, the outer peripheral surface of the cylindrical portion 92 a is press-fitted into the through hole 84 a of the corresponding to-be-removed portion 84, and the inner peripheral surface of the cylindrical portion 92 a corresponds to the shaft 88 on the paper feed roller 54. It is fitted to the outer peripheral surface of the end portion so as to be relatively rotatable. A stop ring 94 is fitted into an annular locking groove 88a (see FIG. 8) formed on the outer peripheral surface of the shaft 88 on the outer side in the axial direction of the bearing member 92. Thus, both end portions of the shaft 88 on the paper feed roller 54 are rotatably supported by the side wall 82 via the bearing member 92. In this state, an annular gap S is formed between each axially outer surface of the to-be-prevented portion 84 and the inner surface of the annular flange 92b of the corresponding bearing member 92 that faces the outer surface in the axial direction. Thus, a partial region in the axial direction on the outer peripheral surface of the cylindrical portion 92a is exposed to the outside (see FIGS. 12 and 13).

A gear 95 is disposed between the roller 90 and one side wall 82 on the shaft 88 of the upper sheet feed roller 54 so as to be integrally rotatable. A spacer 96 is supported on the shaft 88 between the gear 95 and one side wall 82 so as to be relatively rotatable. The gap S between the bearing member 92 and the axially outer surface of the part 84 to be removed can be formed by abutting the tip of the cylindrical portion 92 a of the bearing member 92 against the end surface of the spacer 96.

A pickup roller 56 is disposed in a region closer to the other end than the center in the longitudinal direction of the housing 81 (a region closer to the upper end in the vertical direction in FIGS. 8 to 10). The pickup roller 56 includes a shaft 56A and a roller 56B disposed integrally with the shaft 56A. Both ends of the shaft 56 </ b> A of the pickup roller 56 are rotatably supported by the side walls 82 of the housing 81. On the shaft 56A of the pickup roller 56, a gear 97 is disposed between the roller 54B and one side wall 82 so as to be integrally rotatable. An intermediate gear 98 is disposed on the housing 81 between the pickup roller 56 and the paper feed roller 54. The intermediate gear 98 is disposed so as to be integrally rotatable with the shaft 98A, and the shaft 98A is rotatably supported in the housing 81. The intermediate gear 98 is meshed with the gears 95 and 97. As a result, the upper sheet feed roller 54 and the pickup roller 56 are drive-coupled to rotate in the same direction through the gear 95, the intermediate gear 98, and the gear 97. The gears 95 and 97 incorporate a one-way clutch. The reason for incorporating the one-way clutch is that the sheet fed by the pickup roller 56, the upper sheet feed roller 54, and the lower sheet feed roller 50 is placed in a state where the sheet feed unit 2 is mounted on the apparatus main body as described above. When it is simultaneously transported by a transport roller (not shown) provided in the apparatus main body, the load caused by the speed difference with the transport roller having a high peripheral speed is reduced, and in the jam processing, from the downstream side of the paper feed unit 2 This is to reduce the load when the paper is pulled out.

Referring to FIGS. 6, 7, 10, and 14, the pair of flat outer surfaces 84 a in each of the to-be-prevented portions 84 of the subunit 52 are secured to the bearing portions 76 of the corresponding support walls 74 on the housing 6. When inserted into each notch 80 of the projecting piece 78 and substantially passed, the partial region (region of the gap S) in each cylindrical portion 92a of the bearing member 92 corresponds to the upper portion 6 of the housing. It is supported by the arc surface 76A through the notch 76B of the bearing portion 76. As a result, the subunit 52 is positioned at the insertion position (see FIG. 6). Subsequently, the subunit 52 is rotated (see FIG. 5) and rotated to the closed position where each arcuate outer surface 84b of the to-be-prevented portion 84 comes into contact with the arcuate surface 78A of each of the corresponding protrusions 78 for removal. By moving, the subunit 52 is mounted on the housing 6 (see FIG. 4). Each arcuate outer surface 84a of the to-be-removed part 84 comes into contact with a corresponding pair of arcuate surfaces 78A, thereby preventing the one end of the subunit 52 from coming out radially outward.

Referring to FIGS. 5 and 10, between the subunit 52 and the housing upper 6, there is provided locking means for releasably locking the subunit 52 with respect to the housing upper 6 in the closed position. At the other end portion in the longitudinal direction of the sub unit 52, an elastic hook portion 98 is arranged so that the sub unit 52 extends in a rotating direction from the insertion position (see FIG. 6) toward the closed position (see FIG. 4). . The elastic hook portion 98 is composed of a belt-like main body having elasticity and a hook portion formed at the tip of the main body. On the other hand, a locking hole 102 is formed at a position corresponding to the elastic hook portion 98 of the other end wall 100 disposed at the other end in the width direction of the upper housing 6. When the sub unit 52 is rotated from the insertion position to the closed position as described above, the elastic hook portion 98 is removably engaged with the engagement hole 102 of the upper housing 6. The elastic hook portion 98 and the locking hole 102 constitute the locking means. The elastic hook portion 98 is elastically deformed to release the locking, and the subunit 52 can be easily detached from the upper housing 6 by rotating the subunit 52 in the opposite direction.

Referring to FIG. 10, one end portion of the shaft 88 on the paper feed roller 54 extends outward from the side wall 82 of one side of the housing 81, and the extended one end portion has a semicircular shape. The outer peripheral surface 88a is provided with the flat surface 88b extended in the other end direction from the end of the axis | shaft 88 along an axial center. Referring to FIGS. 6 and 7, one end portion (right end portion in FIG. 7) of driven shaft 58 rotatably supported on housing 6 is formed along a semicircular outer peripheral surface 58a and the axis. And a flat surface 58b extending from one end of the shaft toward the other end. The driven shaft 58 is rotated so that the flat surface 88b at one end of the shaft 88 on the paper feed roller 54 faces the flat surface 58b at one end of the driven shaft 58, and the subunit 52 is paired. By mounting on the support wall 74, one end portion of the shaft 88 on the paper feed roller 54 and one end portion of the driven shaft 58 are drivingly connected so as to be releasable.

A drive gear (not shown) is integrally provided on the drive shaft of the electric motor M provided in the lower housing 4. A gear 104 is disposed at the other end of the driven shaft 58 on the upper housing 6. When the paper feed roller lower 50 is completely attached to the housing lower 4 and the subunit 52 is completely attached to the housing upper 6 (in the state shown in FIG. 4), the housing upper 6 is rotated from the open position to the closed position. By being moved and locked in the closed position, the upper sheet feed roller 54 is pressed against the lower sheet feed roller 50 and the gear 104 is engaged with the drive gear of the electric motor M so that the sheet feed unit 2 can be used. (See FIGS. 1 to 3). A roller 106 is rotatably mounted on the upper housing 6.

At the time of maintenance such as replacing the paper feed roller upper 54 and / or the paper feed roller lower 50, the housing upper 6 is rotated from the closed position to the open position with respect to the housing lower 4 as described above, 4 and the lower surface of the upper housing 6 are exposed to the outside (see FIG. 4). In this state, the lower sheet feed roller 50 can be detached from the lower housing 4 with almost one touch and can be mounted. The subunit 52 can be easily and quickly removed from the housing 6 together with the paper feed roller 54 and can be mounted. Therefore, maintenance of the upper sheet feed roller 54 and / or the lower sheet feed roller 50 can be performed easily and quickly.

1 is a plan view showing a preferred embodiment of a paper feed unit configured according to the present invention. The perspective view which looked at the paper feeding unit shown in FIG. 1 from diagonally right and substantially downward in FIG. 1 is a perspective view of the paper feeding unit shown in FIG. FIG. 2 is a perspective view illustrating a state in which the top of the housing is rotated with respect to the bottom of the housing and opened in the paper feeding unit illustrated in FIG. 1. The perspective view which shows the state in the middle of rotating the subunit toward the closed position by attaching a subunit on a housing in the paper supply unit shown in FIG. The perspective view which shows the state before attaching a subunit on a housing in the paper feed unit shown in FIG. 4, and rotating it toward a closed position. The perspective view which shows the state just before attaching a subunit on a housing in the paper feeding unit shown in FIG. The perspective view which decomposes | disassembles and shows a bearing member and a stop ring in the subunit shown in FIG. The perspective view which shows the state which assembled | attached the bearing member in the subunit shown in FIG. The perspective view which shows the state which assembled | attached the stop ring in the subunit shown in FIG. The perspective view which looked at the subunit shown in FIG. 10 from another angle. The perspective view which looked at the subunit shown in FIG. 10 from another angle. The bottom view of the subunit shown in FIG. The perspective view which expands and shows the support wall of the right side on the housing shown in FIG. The partial perspective view which shows the state which removed the lower part of the paper supply roller from the lower part of the housing in the paper supply unit shown in FIG. In FIG. 15, the partial perspective view which shows the state which mounted | wore under the paper feed roller under the housing. The side view which looked at the right support wall in FIG. 15 from the right side in FIG. FIG. 5 is an exploded perspective view of the paper feeding unit shown in FIG. 4. FIG. 19 is an enlarged perspective view of a bearing portion under the housing in the sheet feeding unit shown in FIG. 18 and showing the right bearing portion in FIG. 18. FIG. 19 is a partial side view showing a state immediately before the shaft portion on the housing is inserted into the bearing portion below the housing in the paper feeding unit shown in FIG. 18. The partial side view which shows the state which inserted the axial part on a housing in the bearing part under a housing (the housing is in an insertion position). The partial side view which shows the rotation state with respect to the bearing part under a housing of the axial part on the housing in the middle of rotating on the housing toward a closed position. The partial side view which shows the rotation state with respect to the bearing part under a housing of the axial part on a housing when rotating on the housing to a closed position. FIG. 19 is a partial perspective view showing a state in the middle of rotating the paper supply unit shown in FIG. FIG. 25 is a partial perspective view showing a state where the housing is further rotated toward the closed position in the paper feeding unit shown in FIG. 24. The partial perspective view which looked at the state shown in FIG. 21 from the left in FIG. The partial perspective view which looked at the state shown in FIG. 22 from the left in FIG. The partial perspective view which looked at the state shown in FIG. 23 from the left in FIG. The partial perspective view which looked at the state rotated on the housing from the closed position shown in FIG. 23 to the open position shown in FIG. 22 from the left in FIG.

Explanation of symbols

2: Feeding unit 4: Lower housing 6: Upper housing 10, 12: Side wall 14, 16: Bearing portion 18: Bearing surface 20: Notch 22, 24: Shaft portion 26, 28: Arc-shaped outer surface 30, 32: Flat Outer surface 50: Lower feed roller 52: Sub unit 54: Upper feed roller 56: Pickup roller

Claims (12)

In a paper feeding unit comprising a synthetic resin housing and a synthetic resin housing that is detachably attached to the lower housing,
The lower part of the housing has bearing portions formed on a pair of side walls disposed on both sides in the longitudinal direction, and each of the bearing portions is disposed on a common axis and is an arc-shaped bearing longer than a semicircle. And a notch comprising a pair of opposing surfaces having a width smaller than the inner diameter of the bearing surface and extending linearly in parallel upward from both ends of the bearing surface and connected to the upper end of the side wall,
The housing has shaft portions arranged on a common axis and extending outward from a pair of side walls disposed on both sides in the longitudinal direction, each of the shaft portions having a radius sandwiching the shaft center. A pair of arcuate outer surfaces arranged at symmetrical positions in a direction and a pair of flat surfaces arranged at other symmetrical positions in the radial direction across the axis and extending in parallel between both ends of the arcuate outer surface With an outer surface,
A pair of flat outer surfaces in each of the shaft portions on the housing is inserted from above into the corresponding notch of the bearing portion under the housing and passed substantially so that one of the arc-shaped outer surfaces comes into contact with the bearing surface. It is received and the housing is positioned at the insertion position, and then, on the housing, one of the rotating directions to the closed position where at least a partial region in the circumferential direction of each of the arc-shaped outer surfaces of the shaft portions contacts the bearing surface. The housing is mounted on the bottom of the housing by rotating
A paper feeding unit characterized by that. One side wall disposed on one side in the longitudinal direction on the housing is a sliding protrusion that protrudes outward from the one side wall toward the one side wall in the lower surface direction on the housing. A sliding protrusion having an inclined surface that is inclined in the axial direction of the shaft portion, and a positioning protrusion that extends outward in the width direction from the one end portion in the width direction of the housing and outward in the radial direction with respect to the shaft portion; A partial region of the inner corner at the upper end of one side wall under the housing is positioned so as to exist on a rotation locus in one rotation direction of the inclined surface of the sliding projection,
A movement-preventing wall that prevents the positioning protrusion from moving in the other rotational direction is disposed at one side area under the housing and inside the space with respect to one side wall under the housing. And
In a state where the top of the housing is positioned at the insertion position, the positioning protrusion on the housing is positioned so as to be rotatable in one rotational direction within the space under the housing,
When the housing is rotated in one direction from the insertion position to the closed position, the inclined surface of the sliding projection on the housing is part of the inner corner at the upper end of one side wall under the housing. By being brought into contact with the region and being relatively moved inward in the axial direction, each of the shaft portions on the housing is slid in the axial direction from one of the longitudinal directions on the housing to the other with respect to the corresponding bearing surface. Then, the entire upper surface of the housing is slid in the same direction, and is positioned at the closed position. By the sliding movement on the housing, the movement-preventing wall surface below the housing moves to the other rotation direction of the positioning protrusion on the housing. Is positioned relatively on the rotation trajectory of
When the top of the housing is rotated from the closed position to the open position in the other rotational direction, the positioning protrusion on the housing is brought into contact with the movement-preventing wall surface under the housing and moves in the other rotational direction. The sheet feeding unit according to claim 1, wherein movement is prevented and the housing is positioned in an open position. The supply angle according to claim 2, wherein a rotation angle in the other rotation direction from the closed position to the open position on the housing is smaller than a rotation angle in the other rotation direction from the closed position to the insertion position. Paper unit. The sheet feeding device according to any one of claims 1 to 3, wherein locking means for releasably locking the upper portion of the housing to the closed position relative to the lower portion of the housing is disposed between the upper portion and the lower portion of the housing. unit. In a paper feeding unit comprising a synthetic resin housing, and a synthetic resin housing that is rotatably and detachably mounted between an open position and a closed position with respect to the housing,
At the center in the longitudinal direction under the housing, the lower part of the feed roller is rotatably and detachably disposed.
A sub-unit is detachably attached to the longitudinal center of the housing, and a sub-unit is rotatably mounted on a paper feed roller and a pickup roller.
A driven shaft is rotatably supported on one side region in the longitudinal direction with the subunit as a boundary on the housing,
A drive source is arranged under the housing,
When the sub unit is mounted on the housing, the feed roller and the driven shaft are releasably driven and connected,
When the housing is rotated from the open position to the closed position, the upper side of the paper feed roller on the housing is pressed against the lower side of the paper feed roller below the housing, and the driven shaft is releasably connected to the drive source.
A paper feeding unit characterized by that. A pair of support walls are disposed at a central portion in the longitudinal direction below the housing at intervals in the longitudinal direction, and a bearing portion having an open upper end is disposed at each upper end portion of the support wall. The lower roller includes a shaft and a roller rotatably supported by the shaft, and both ends of the shaft are mounted so as not to rotate relative to the bearing portions of the corresponding support wall and to be detachable. 5. The paper feeding unit according to 5. Each of the bearing portions in each of the support walls has a pair of side walls facing each other in parallel to the plane across an imaginary plane passing through the axis and extending in the vertical direction, and from the middle region of one side wall to the lower end of the other side wall. A bottom wall extending in a circular arc shape toward the top, and a protrusion extending inward is formed at the upper end of one side wall, and both end portions of the shaft below the feed roller have an arc-shaped outer peripheral surface, a shaft A flat surface extending in the axial direction approaching each other from the tip of the shaft, and the flat surface at both ends of the shaft is pressed against the other side wall of the corresponding support wall under the feed roller and both ends of the shaft 7. The sheet feeding unit according to claim 6, wherein the arcuate outer peripheral surface of the portion is held in contact with the side wall and the bottom wall substantially over the projection on one side wall of the corresponding support wall. . A pair of support walls are disposed at a longitudinally central portion on the lower surface side of the housing, and are spaced apart in the longitudinal direction. When the driven shaft is rotatably supported, the subunit is detachably mounted between the pair of support walls, and the subunit is mounted between the pair of support walls, the sub-unit feed roller is placed on the driven roller. The paper feed unit according to any one of claims 5 to 7, wherein the paper feed unit is removably connected to one end of the drive shaft. Each of the support walls is formed with a bearing portion and a retaining portion. Each of the bearing portions includes a semicircular bearing surface disposed on the same axis as the driven shaft, and an upper side from both ends of the bearing surface. And a notch formed of a pair of opposed surfaces connected to the upper end of the support wall, and each retaining portion is disposed inside the support wall with the bearing portion sandwiched in the width direction on the housing. The arcuate surfaces concentric with the axis formed on the mutually opposing surfaces of the pair of retaining protrusions, and having a width smaller than the inner diameter of each of the arcuate surfaces and from the upper end of each of the arcuate surfaces A notch formed of a pair of opposing surfaces that extend in a straight line parallel to the upper side and connected to the upper end of the support wall;
The sub-unit includes a pair of side walls, and each of the side walls is provided with an annular portion to be prevented from projecting laterally outward, and each of the portions to be removed has a through hole having a common axis and an axis. A pair of arcuate outer surfaces arranged at symmetrical positions in the radial direction sandwiched between and a pair of other radial positions in the radial direction across the axis and extending in parallel between both ends of the arcuate outer surface A pair of flat outer surfaces,
On the paper feed roller, a shaft and a roller integrated with the shaft are provided, and both end portions of the shaft on the paper feed roller are rotatably supported in through holes of the to-be-removed portion via bearing members. Each of the bearing members includes a cylindrical portion and an annular flange extending radially outward from one axial outer peripheral surface of the cylindrical portion, and the outer peripheral surface of the cylindrical portion penetrates the corresponding portion to be removed. The inner peripheral surface of the cylindrical portion is press-fitted into the hole, and is fitted to the outer peripheral surface of the end portion of the shaft so as to be relatively rotatable, and the axially outer surface of each to-be-removed portion and the annular flange of the corresponding bearing member In addition, an annular gap is formed between the outer surface and the inner surface facing in the axial direction, and a partial region in the axial direction on the outer peripheral surface of the cylindrical portion is exposed to the outside.
When a pair of flat outer surfaces in each of the to-be-prevented portions of the subunit are inserted into the notches in the corresponding to-be-prevented portions on the housing and substantially passed, the partial regions in each cylindrical portion of the bearing member are The subunit is positioned at the insertion position by being supported by the arc surface through the corresponding notch of the bearing on the housing, and then the subunit is associated with each arc-shaped outer surface of the to-be-removed portion. The sheet feeding unit according to claim 8, wherein the subunit is mounted on the housing by rotating to a closed position in contact with the arc surface in the retaining portion. 10. The paper feeding unit according to claim 9, wherein a locking means for releasably locking the subunit to the closed position with respect to the housing is disposed between the subunit and the housing. One end of the shaft on the paper feed roller disposed in the subunit includes a semicircular outer peripheral surface and a flat surface extending from one end of the shaft to the other end along the shaft center. One end of the driven shaft that is rotatably supported by the shaft includes a semicircular outer peripheral surface and a flat surface extending from one end of the shaft to the other end along the shaft center. By attaching the subunit to the pair of support walls so that the flat surface at one end of the shaft is opposed to the flat surface at one end of the driven shaft, The paper feeding unit according to claim 9, wherein the paper feeding unit is releasably connected to one end of the driven shaft. The drive source under the housing is an electric motor, the drive gear is integrally disposed on the drive shaft of the electric motor, and the driven gear is integrally disposed on the other end of the driven shaft on the housing, 12. The paper feeding unit according to claim 11, wherein when the upper side of the housing is positioned at a closed position with respect to the lower side of the housing, the driven gear of the driven shaft is releasably connected to the driving gear of the electric motor.

Images