JP2017146550A - Image forming apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology of a hinge that can prevent deformation and come-off of a support shaft and improve workability during maintenance.SOLUTION: An image forming apparatus comprises: a main body that includes image forming means that can form an image on a sheet; a sheet placement part on which the sheet having the image formed thereon by the image forming means and ejected from the main body is placed; a rotating body that is provided above the sheet placement part rotatably with respect to the main body with a space from the sheet placement part; and hinge means that each include a support shaft inserted into a first shaft hole provided on the main body side and a second shaft hole provided on the rotating body side and connect the main body and the rotating body. The support shaft includes an engagement part that elastically engages with the first shaft hole or the second shaft hole, at a position different from a position on which the maximum stress acts when the rotating body is further pressed onto a space with the sheet placement part while the rotating body is at a closed position with respect to the main body.SELECTED DRAWING: Figure 11

Description

  The present invention relates to an image forming apparatus.

  Various image forming apparatuses such as copying machines and image reading apparatuses widely employ a configuration in which a phase hinge mechanism is interposed between two members so that the two members are connected to each other so as to be relatively rotatable. As an example, the hinge mechanism is provided at the rotation support portion between the document pressing plate and the apparatus main body for holding the document set on the document table. In such a hinge mechanism, there is a mechanism in which a support shaft on the apparatus main body side is inserted into a bearing hole of a rotating arm extending from the original pressure plate side. In this case, in order to omit the axial retaining part, an insertion slot is formed so as to cut out a part of the bearing hole. The support shaft is attached to the bearing hole through the insertion slot, and the support shaft is prevented from being detached from the insertion slot when the original cover is rotated. However, in such a hinge mechanism, there is a problem that the bearing rigidity tends to decrease due to the insertion slot, which causes a problem in strength.

  Patent Document 1 proposes a technique for solving the above problem. FIG. 13 shows a hinge mechanism described in Patent Document 1. The hinge mechanism is provided with push-up convex portions 14d and 15c on the boss portion 15a side or the ribs 14b and 14c side of the first and second rotating bodies 14 and 15, respectively. The first and second rotating bodies 14 and 15 are once out of the usable rotation angle range, the push-up convex portions 14d and 15c are separated, and the first and second rotating bodies 14 and 15 are rattled. Put in the state with the mark. In this way, the hinge support shaft 16 is easily inserted into the first and second rotating bodies 14 and 15. After the hinge support shaft 16 is inserted, the first and second rotating bodies 14 and 15 are rotated within a usable rotation angle range. The push-up convex portions 14d and 15c provided on the boss portion 15a side or the ribs 14b and 14c side are brought into pressure contact, and the retaining engagement piece 14c2 is inserted into the retaining locking groove 16a to prevent the hinge support shaft 16 from coming off in the axial direction. Let it be done. With the above configuration, good bearing rigidity can be obtained with a simple configuration, and it can be easily disassembled.

JP 2003-148446 A

  However, with the technique described in Patent Document 1, it is difficult to insert the support shaft unless it is outside the rotation angle range of use, and workability is difficult. In addition, when a retaining shape is formed by forming a claw shape or the like on the support shaft side, it can be inserted even outside the operating rotation angle range. However, in a configuration where a load can be applied to the rotating body within the operating rotation angle range, the claw The shape is deformed or damaged. By doing so, there was a problem that the support shaft would come off.

  An object of the present invention is to provide a technique of a hinge that can prevent deformation and removal of a support shaft and improve workability during maintenance.

  According to the present invention, for example, a main body including an image forming unit capable of forming an image on a sheet, and a sheet mounting unit on which a sheet on which an image is formed by the image forming unit and discharged from the main body is mounted. A rotating body provided above the sheet placing portion so as to be rotatable with respect to the main body with a space between the sheet placing portion and a first shaft hole provided on the main body side; A support shaft inserted into a second shaft hole provided on the rotating body side; and a hinge means for connecting the main body and the rotating body. The support shaft includes the rotating body and the main body. The first shaft hole or the first shaft hole is located at a position different from the position where the maximum stress acts when the rotating body is further pressed to the space side with respect to the sheet placement portion in the closed position. Image forming characterized by having an engaging portion that elastically engages two shaft holes Location is provided.

  ADVANTAGE OF THE INVENTION According to this invention, the technique of the hinge which can prevent a support shaft's deformation | transformation and omission and can improve workability | operativity at the time of a maintenance can be provided.

1 is a perspective view of an image forming apparatus according to an embodiment. FIG. 3 is a perspective view when the image reading apparatus is rotated within a use range. The perspective view which looked at the image forming apparatus from the back side. The perspective view of a hinge mechanism. The exploded perspective view of a hinge mechanism. The exploded perspective view of the hinge mechanism which pulled out the support shaft. The perspective view of a hinge mechanism. (A), (B) is a perspective view of a support shaft, (C), (D) is a perspective view of a rib. The perspective view which looked at the image forming apparatus from the bottom side. The perspective view which looked at the image forming apparatus from the back upper side. FIG. 3 is a simple schematic view of the image reading device and the hinge portion as viewed from the left side. The detailed schematic diagram seen from the left surface of the image reading device and the hinge part. The exploded perspective view of the conventional hinge part.

  Embodiments of the present invention will be described below with reference to the drawings. Throughout the drawings, the same reference numerals indicate the same or corresponding parts. Further, in the following description, the vertical and horizontal directions in the drawings are used for description as the apparatus or the vertical and horizontal directions of each component described below.

  The present invention will be described by taking an image forming apparatus such as an electrophotographic system or an electrostatic recording system as an example. However, the image forming apparatus of the present invention can employ an inkjet system, a thermal transfer system, various printing systems, etc., instead of the electrophotographic image forming apparatus. Furthermore, the image forming apparatus of the present invention is not limited to a printer, and various apparatuses such as various printing machines, copiers, FAX machines, multifunction machines, and the like can be adopted.

  FIG. 1 is a perspective view of an image forming apparatus 1 according to an embodiment of the present invention. The image forming apparatus 1 includes a reading device (rotating body) 3 that reads an image on a main body 2 of the image forming apparatus, and includes an operation unit 4. The reading device 3 is rotatably connected to the main body via a hinge mechanism (hinge portion) 7 described later. An image read by the reading device 3 is formed on a recording medium (medium) by an image forming unit (not shown) disposed in the main body 2. The recording medium is transported by a transport unit (not shown) disposed in the main body 2 and discharged to the outside of the main body 2 through, for example, a discharge port 5 described later.

  FIG. 2 is a perspective view when the reading device 3 is rotated with respect to the main body 2 within a use range. In the image forming apparatus 1, a paper jam occurs at the paper discharge port 5, and the state of the paper discharge port 5 becomes invisible by the operation unit 4 when performing this process. Therefore, the reading device 3 is rotated upward to make the state of the paper discharge port 5 visible and to secure a processing operation area. The rotation area of the reading device 3 with respect to the main body 2 is restricted by providing a connecting member 6 between the reading device 3 and the main body 2 so as not to rotate more than a certain angle.

  FIG. 3 is a perspective view of the image forming apparatus 1 as viewed from the back side. The reading device 3 is rotatably connected to the main body 2 by two hinge mechanisms 7 that are spaced apart in series in the axial direction.

  FIG. 4 is a perspective view of one hinge mechanism 7 (the right hinge mechanism 7 in FIG. 3). The hinge mechanism 7 includes a hinge cradle 200 provided in the main body 2, a hinge part (boss) 100 provided in the reading device 3, and a hinge shaft (support shaft) inserted through the hinge cradle 200 and the hinge part 100. ) 300. Therefore, the hinge portion 100 provided in the reading device 3 is connected to the hinge base 200 attached to the main body 2 by the hinge shaft 300. In addition, arrangement | positioning of the hinge base 200 and the hinge part 100 is not limited to said form, For example, as another embodiment, the hinge base 200 is provided in the reader 3, for example, and the hinge part 100 is provided in the main body 2. It may be adopted.

  FIGS. 5 to 7 are exploded perspective views of the hinge mechanism 7 showing how the reading device 3 and the main body 2 are connected by the hinge mechanism 7. In FIG. 5, the disassembled perspective view before the hinge part 100, the hinge cradle 200, and the hinge shaft 300 are assembled is shown.

  The hinge cradle 200 includes a pair of ribs 201 and 202. Through holes (bearing holes) 203 and 204 are formed in the pair of ribs 201 and 202. The hinge part 100 is disposed between the pair of ribs 201 and 202. A through hole (shaft hole) 101 is formed in the hinge part 100. The hinge shaft 300 has a claw-shaped engagement portion 301 that is inserted into the through holes 101, 203, and 204 and elastically engages with the rib 202. The through holes 101, 203, and 204 have the same diameter, and the diameter is slightly larger than the shaft diameter of the hinge shaft 300.

  As shown in FIG. 6, when connecting the reading device 3 and the main body 2, the hinge portion 100 is disposed between the pair of ribs 201 and 202 so that the through hole 101 is concentric with the through holes 203 and 204. Next, the reading device 3 and the main body 2 are connected by passing the hinge shaft 300 through the through holes 101, 203, 204 in the direction indicated by the arrow A from right to left in FIG. 6 (see FIG. 7).

  8A to 8D are perspective views of the hinge cradle 200 and the hinge shaft 300. FIG. FIG. 8A shows a perspective view of the hinge shaft 300 viewed from one side in the axial direction, and FIG. 8B shows a perspective view seen from the other side.

  The hinge shaft 300 includes a columnar body 300a having a non-circular cross-section with a part cut away in the circumferential direction, and an engagement portion 301 extending in the axial direction at the cut-out portion. The engaging portion 301 includes an engaging claw 301a that protrudes radially outward from the outer peripheral surface of the main body portion 300a, and a bending portion 301b that deflects the engaging claw 301a in the radial direction. The engaging claw 301a is arranged at the end of one side of the hinge shaft 300 in the axial direction (the middle front side in FIG. 8A). The flexure 301b is a plate-like member that is connected to the engaging claw 301a on one axial side of the hinge shaft 300 and extends a predetermined distance toward the other axial side of the hinge shaft 300 (the front side in FIG. 8B). A space is formed between the bent portion 301b and the main body portion 300a, and the engaging claw 301a and the bent portion 301b are configured to be movable radially inward with respect to the main body portion 300a.

  The hinge shaft 300 includes a ridge 302 that protrudes radially outward from the outer peripheral surface of the main body 300a at the other end in the axial direction and extends in the circumferential direction. In this embodiment, the protrusion 302 forms a non-circular shape with a part cut away in the circumferential direction. The protrusion 302 is formed so as to protrude from the outer peripheral surface of the main body 300a over the entire circumference in the circumferential direction except for the notched portion. In addition, the hinge shaft 300 includes a plurality of guide portions 303 and 304 that protrude outward from the outer peripheral surface of the main body portion 300a and extend in the axial direction, adjacent to the protruding portion 302, at the other end. The radial heights of the guide portions 303 and 304 are set to the same height as the radial height of the ridge portion 302. The axial lengths of the guide portions 303 and 304 are formed to be shorter than the axial length of the rib described later.

  FIG. 8C shows a perspective view of the hinge cradle 200 viewed from one side in the axial direction, and FIG. 8D shows a perspective view seen from the other side. A through hole 204 penetrating in the thickness direction is formed in the rib 202 on one axial side (the middle front side in FIG. 8C) of the pair of ribs of the hinge base 200. An engaged portion 206 that engages with the engaging claw 301a is formed on the end surface (outer end portion) on one axial side of the rib 202. The engaged portion 206 is an annular recess that is formed over the entire circumference adjacent to the through hole 204 and is recessed inward of the rib 202. By doing so, the engaging claw 301a can be engaged with any portion of the engaged portion 206. The engaged portion 206 is not limited to the annular recess, and is provided at a predetermined position that defines an arbitrary position of the engaging claw 301 a with respect to the rib 202 when the hinge shaft 300 is inserted into the through hole 204. Also good. By doing so, the engaged portion 206 can prevent the hinge shaft 300 from coming off in the axial direction and can be positioned in the circumferential direction.

  A through hole 203 penetrating in the thickness direction is formed in the rib 201 on the other axial side (the middle front side in FIG. 8D) of the pair of ribs of the hinge base 200. Further, a circumferential groove 205 that accommodates the protrusion 302 is formed on the other end surface (outer end) in the axial direction of the rib 201. The circumferential groove 205 is an annular recess that is formed over the entire circumference adjacent to the through hole 204 and is recessed inward of the rib 202. By doing so, the protrusion 302 is accommodated in the circumferential groove 205 over the entire circumference. The circumferential groove 205 is not limited to the annular recess, but may be a non-circular shape corresponding to the shape of the protrusion 302. By doing so, the circumferential groove 205 can position the hinge shaft 300 in the circumferential direction.

  Guided portions 207 and 208 that engage with the guide portions 303 and 304 of the hinge shaft 300 are formed on the inner peripheral surface of the through hole 203. In the present embodiment, two guided portions 207 and 208 are arranged corresponding to the number of guide portions 303 and 304 of the hinge shaft 300, and are arranged at positions that form an angle of 90 ° with each other. In the present embodiment, the guided portions 207 and 208 are formed so as to penetrate through the through hole 203 in the axial direction.

  Here, as shown in FIG. 6, when the hinge shaft 300 is inserted through the hinge portion 100 and the hinge cradle 200, the state shown in FIG. 7 is obtained. At this time, the engaging claw 301 a of the hinge shaft 300 is engaged with the engaged portion 206 of the rib 202, and the protrusion 302 of the hinge shaft 300 is accommodated in the circumferential groove 205 of the rib 201. By doing so, the hinge shaft 300 is prevented from being axially positioned and coming off from the pair of ribs 201 and 202. Further, the guide shafts 303 and 304 are engaged with the guided portions 207 and 208, whereby the hinge shaft 300 is prevented from rotating relative to the rib 201.

  When the hinge part 100 is inserted into the hinge cradle 200, the axial position of the hinge part 100 is determined to be within a range in which the hinge part 100 moves slightly in the axial direction. That is, the axial length of the hinge shaft 100 is set slightly shorter than the distance between the pair of ribs 201 and 202 of the hinge receiver 200. The radial position of the hinge portion 100 is determined by the hinge shaft 300 and the through hole 101, but is determined to be within a range in which the hinge portion 100 moves slightly in the radial direction. That is, the outer diameter of the hinge shaft 100 is set slightly smaller than the inner diameter of the hinge portion 100.

  FIG. 9 is a perspective view of the image forming apparatus 1 in a state where the reading device 3 in FIG. On the bottom surface of the reading device 3, a plurality of protrusions (contact members) 8, 9, and 10 that are positioned by contacting the top surface of the main body 2 are disposed. The protrusions 8, 9, 10 include two protrusions 8, 10 disposed in parallel with the two hinge mechanisms 7, 7 arranged in series in the axial direction, and the hinge mechanism 7 from the two protrusions 8, 10. Includes one protrusion 9 that is spaced apart on the opposite side. Therefore, in this embodiment, the three protrusions 8, 9, and 10 are arranged in a substantially L shape in plan view. The upper surface of the main body 2 has a substantially L-shaped plane in plan view so as to be able to abut on the three protrusions 8, 9, 10 arranged in a substantially L-shape in plan view. Therefore, the reading device 3 includes protrusions 8, 9, 10 that protrude from the side facing the main body 2 and can come into contact with the main body 2, and in the closed position (see FIG. 1) closed with respect to the main body 2. It is supported on the main body 2 by the mechanisms 7, 7 and the protrusions 8, 9, 10.

  In addition, in this embodiment, although the three projection parts are arrange | positioned, it is not limited to this, At least one projection part may be arrange | positioned. Moreover, although the two hinge mechanisms 7 are arrange | positioned in this embodiment, it is not limited to this, At least 1 may be arrange | positioned.

  FIG. 10 is a perspective view of the image forming apparatus 1 in the closed position where the reading device 3 is closed with respect to the main body 2. The main body 2 is connected to the paper discharge port 5 at the left front as viewed from the front of the main body 2 (FIG. 1), and is provided with a space 11 as a paper discharge portion. Is not touching. According to the image forming apparatus 1 having such a configuration, when the reading device 3 is rotated within the use range and moved to the closed position, or when it is in a stationary state at the closed position, for example, FIG. The reading device 3 may be pressed downward from the top indicated by the arrow B. When the user closes the reading device 3 from the opened state or when a document pressing plate is employed instead of the reading device 3 described later, the user may suddenly and strongly press the reading device 3 downward. is there.

  In such a case, it is understood that a large load is applied to the reading device 3 and the left rear (front side in FIG. 10) by pressing the reading device 3 vertically downward within the space 11. ing. When the reading device 3 is pressed vertically downward, a stress is applied to the hinge shaft 300 in the radial direction via the hinge portion 100 of the reading device 3, and this stress depends on the circumferential position of the engaging portion 301. The bending part 301b of the engaging part 301 is bent, and the hinge shaft 300 may come off or be damaged. Therefore, the engaging portion 301 needs to be arranged at a position where the influence of the stress is small in the circumferential direction of the hinge shaft 300.

  FIG. 11 is a schematic diagram of a CC cross section of the reading device 3 including the hinge mechanism 7 in FIG. Specifically, it is a diagram illustrating a relationship between forces acting on the reading device 3 and the hinge mechanism 7 when the reading device 3 is pressed from above corresponding to the range of the space 11. Point A (point of action) is on the circumference of the hinge shaft 300 and is assumed to be a point inclined at an angle Θ in the horizontal direction from the center of the hinge shaft 300, and indicates the position of the engaging claw 301a of the engaging portion 301. . Point B (fulcrum) is a point where the protrusion 8 and the main body 2 are in contact with each other, and the horizontal distance from the center of the hinge shaft 300 is x. At this time, the line segment AB connecting the point B and the point A was assumed to have a length l and an inclination α. A point C (power point) indicates a position where the reading device 3 is pressed. The pressing force is F, and the length of the line segment BC connected to the point B is L. At this time, the stress applied to the point A of the hinge shaft 300 was assumed to be f. In order to guide the circumferential position of the engagement portion 301 to a position where the influence of the stress is small, the stress applied to the engagement claw 301a of the engagement portion 301 when the reading device 3 is pressed in the space 11 is reduced. It only needs to be minimum. Therefore, by obtaining Θ that minimizes f, the position of the engaging portion 301 can be made less affected by the stress.

  FIG. 12 is a schematic diagram in which FIG. 11 is further detailed in order to guide the position of the engaging portion 301. First, when the reading device 3 is pressed in the range of the space 11, the reading device 3 is in a stationary state. At this time, f · l = F ′ · L holds from the balance of moments around the point B. However, F 'is an orthogonal component with respect to F line segment BC. Further, the direction in which the engaging portion 301 bends is a direction orthogonal to the circumferential tangent direction of the hinge shaft 300. If the direction component of f in this direction is set to f ′, Θ that minimizes f ′ can be obtained. The position of the engaging portion 301 is less affected by the stress. The distance from the point B in the vertical direction of the hinge shaft 300 is y, and the radius is r. From the above, Θ that actually minimizes f ′ is obtained.

  From balancing moments

From the three-square theorem

here

And put

Next, from FIG.

From the additive theorem

Substituting I, II, and IV into III

  As described above, f ′ can be expressed as an equation having only a variable Θ, and Θ that minimizes f ′ is obtained, so that the position of the engaging portion 301 can be optimized.

  Next, Table 1 shows the result of obtaining f 'by substituting a predetermined numerical value for Θ. Since the value of f ′ is an example for comparison of how much force is acting on each Θ, common values of F ′, L, etc. are adopted. Omitted numbers are omitted.

  As shown in Table 1, when Θ is 90 °, breakage of the engaging claws 301a of the engaging portion 301 was observed. Further, when Θ was 135 °, the engaging portion 301 was bent and the engaging claw 301a was detached from the engaged portion 206. When Θ was 180 °, good results were obtained with no bending of the engaging portion 301 and no damage to the engaging claws 301a. When Θ was 270 °, breakage of the engaging claws 301a of the engaging portion 301 was observed.

  As described above, in this embodiment, when Θ is around 180 °, the position of the engaging portion 301 can be set to a position where the influence of the stress is small. Note that the position where Θ is around 180 ° is a position where the influence of the stress is small, but the range of the position near this can be changed as appropriate depending on, for example, the ease of bending of the bending portion 301b of the engaging portion 301. Therefore, the present invention is not limited to the vicinity of 180 °, and can be realized within a range that can be set by a person skilled in the art in order to achieve the above object.

  Therefore, the engaging portion 301 whose rigidity is weakened on the hinge shaft 300 can be disposed at a position where the influence of the stress is small. Therefore, in the closed position shown in FIG. 10, the hinge shaft 300 is applied to the main body 2 when a force F that pushes the reading device 3 toward the main body 2 is applied to the protrusion 8 on the side opposite to the hinge mechanism 7. The rigidity of the side pressed against the provided ribs 201 and 202 (Θ is near 0 °) can be increased. That is, the engaging portion 301 whose rigidity is weakened is not arranged on the hinge shaft 300 whose Θ is near 180 ° and Θ is near 0 °. In other words, the engaging portion 301 is disposed so as to avoid the side on which the rigidity of the hinge shaft 300 is increased (Θ is around 0 °).

  The guide portions 303 and 304 may be formed on the side on which the rigidity of the hinge shaft 300 is increased (Θ is near 0 °). By doing so, the guide portions 303 and 304 become ribs extending in the axial direction of the hinge shaft 300, and the rigidity of the hinge shaft 300 can be increased.

  As described above, according to the hinge mechanism 7 of the present embodiment, the workability of attaching the main body 2 and the reading device 3 is easy, and the configuration of the image forming apparatus 1 in which the hinge shaft 300 is less likely to be detached or damaged is possible. become. Further, it is possible to provide an image forming apparatus or an image reading apparatus provided with the hinge mechanism 7 in which the hinge shaft 300 does not come out even when a load is applied within the use rotation angle range.

  Further, according to the present embodiment, when the main body 2 and the reading device 3 are connected, the hinge shaft 300 can be inserted regardless of the relative angle of each other, so that workability is improved. Further, by inserting the hinge shaft 300, it is possible to realize the retaining by the engaging claws 301a simultaneously with the determination of the position in the rotation direction by the guide portions 303 and 304. Since the position of the engaging portion 301 in the circumferential direction is also determined, the position of the engaging claw 301a is the position at which the stress applied to the engaging claw 301a is minimized when the reading device 3 is loaded within the operating rotation angle range. It can be. Accordingly, it is possible to prevent the guide shaft 300 from coming off due to deformation or breakage of the engaging claw 301a.

  In this embodiment, the main body includes an image forming unit that forms an image on a medium, and the reading device includes a reading unit that reads a document. However, the main body may include a reading unit that reads a document, and instead of the reading device, a document pressing plate or a document conveying unit that conveys the document may be employed. The “medium” is assumed to be sheet-like paper, but may be cloth, plastic film, or the like.

DESCRIPTION OF SYMBOLS 1 Image forming apparatus, 2 Main body, 3 Reading apparatus, 4 Operation part, 5 Paper discharge port, 6 Connecting member, 7 Hinge mechanism, 8 Protrusion part, 9 Protrusion part, 10 Protrusion part, 11 Space, 100 Hinge part, 101 Through Hole, 200 hinge cradle, 201 rib, 202 rib, 203 through hole, 204 through hole, 205 circumferential groove, 206 engaged portion, 207 guided portion, 208 guided portion, 300 hinge shaft, 301 engaging portion 302 ridge, 303 guide, 304 guide

Claims (12)

A main body provided with image forming means capable of forming an image on a sheet;
An image is formed by the image forming unit, and a sheet placing portion on which a sheet discharged from the main body is placed;
Above the sheet placement unit, the sheet placement unit and a rotating body provided to be rotatable with respect to the main body with a space therebetween,
A support shaft that is inserted into a first shaft hole provided on the main body side and a second shaft hole provided on the rotating body side; and a hinge means that connects the main body and the rotating body. ,
The support shaft is
At a position different from the position where the maximum stress acts when the rotating body is further pressed to the space side with respect to the sheet placing portion in a state where the rotating body is in the closed position with respect to the main body. An image forming apparatus comprising an engaging portion that elastically engages with the second shaft hole or the second shaft hole. The hinge means is
A pair of ribs provided with the first shaft hole or the second shaft hole;
A boss provided with the first shaft hole or the second shaft hole and disposed between the pair of ribs;
The image forming apparatus according to claim 1, wherein the support shaft connects the main body and the rotating body by being inserted through the first shaft hole and the second shaft hole. The rotating body includes a contact member capable of contacting the main body,
The rotating body is not in contact with the main body at a position other than the hinge means and the contact member on a line connecting the hinge means and the contact member when in the closed position. The image forming apparatus according to claim 1.   The engaging portion includes an engaging claw that protrudes radially outward from an outer peripheral surface of the support shaft, and a bending portion that deflects the engaging claw in the radial direction, and the rib or the support shaft The image forming apparatus according to claim 2, wherein the image forming apparatus is disposed on a side opposite to a side pressed against the boss. The pair of ribs are provided on the main body,
The image forming apparatus according to claim 2, wherein the boss is provided on the rotating body. The support shaft includes the engaging claw at one end in the axial direction, and a ridge extending in the circumferential direction by projecting radially outward from the outer peripheral surface of the support shaft at the other end in the axial direction. Prepared,
One of the pair of ribs includes an engaged portion that engages with the engaging claw at an outer end in the axial direction.
The other of the pair of ribs includes a circumferential groove that accommodates the protruding portion at an axially outer end,
When the support shaft is inserted into the pair of ribs, the engaging claw engages with the engaged portion, and the protruding portion is received in the circumferential groove, whereby the support shaft is 6. The image forming apparatus according to claim 2, wherein axial positioning and drop-off from the pair of ribs are prevented. The support shaft includes, at the other end, a guide portion that protrudes outward from the outer peripheral surface of the support shaft and extends in the axial direction.
The other rib includes a guided portion that engages with the guide portion on an inner peripheral surface of the bearing hole,
The image forming apparatus according to claim 2, wherein the support shaft is prevented from rotating relative to the rib by engaging the guide portion with the guided portion. .   The image forming apparatus according to claim 7, wherein the guide portion is formed shorter than an axial length of the other rib.   The image forming apparatus according to claim 7, wherein the guide portion is formed on a side of the support shaft that is pressed against the rib or the boss. Two of the hinge means are arranged so as to be arranged in series in the axial direction of the support shaft with respect to the main body,
The abutting member is arranged in three, including two arranged in parallel with the hinge means and one arranged apart from the two on the side opposite to the hinge means. The image forming apparatus according to claim 3.   The image forming apparatus according to claim 1, wherein the rotating body includes a reading unit that reads a document.   The image forming apparatus according to claim 1, wherein the rotating body includes a document pressing plate or a document conveying unit that conveys a document.