JP2017081738A - Sheet guide mechanism and image formation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet guide mechanism in which performing of jam processing on a transportation path is easy, capable of displacing one of a pair of sheet guide parts to a guide position of the transportation path and an isolation position by an intuitive and easy operation.SOLUTION: An elastic member 14 expands/contracts according to rotation of a second sheet guide part 12. In a case where the second sheet guide part is present at a guide position, the elastic member 14 applies an elastic force against a torque to an isolation position side to the second sheet guide part, so that the second sheet guide part 12 is held at the guide position. In a case where the second sheet guide part 12 is present at the isolation position, the elastic member 14 applies the elastic force against the torque to the guide position side to the second sheet guide part 12, so that the second sheet guide part 12 is held at the guide position.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a sheet guide mechanism and an image forming apparatus.

  Generally, an image forming apparatus includes a sheet guide mechanism that guides a sheet material that is an image forming medium. For example, the sheet guide mechanism is provided above a sheet cassette that can be pulled out from the apparatus main body. In this case, in the sheet guide mechanism, the lower sheet guide portion of the pair of upper and lower sheet guide portions is supported to be rotatable in the vertical direction.

  In the state where the sheet cassette is pulled out from the apparatus main body, the lower sheet guide portion is pulled downward, whereby jamming of the conveyance path is possible.

  In the sheet guide mechanism above the sheet cassette, it is known that the lower sheet guide portion is held at an upper guide position along the conveyance path by an elastic force of a spring (for example, a patent) Reference 1). In this case, a lock mechanism for locking the sheet guide portion at the guide position is not required.

  Therefore, the user does not need to perform an operation of releasing the lock mechanism. Furthermore, the user can perform the jam processing by displacing the sheet guide portion to a separation position separated from the conveyance path by an intuitive and simple operation.

JP 2005-315920 A

  By the way, when one of the sheet guide portions supported rotatably is held at a guide position along the conveyance path by the elastic force of a spring, the user must perform the jam processing with one hand.

  That is, the user needs to perform the jam processing with the other hand while holding the sheet guide portion at a separated position separated from the conveyance path with one hand. However, it may be more convenient to use both hands in the jam processing.

  It is also conceivable that the sheet guide mechanism includes a lock mechanism that locks the sheet guide portion at the separation position. In this case, the user has to learn an operation of releasing the lock of the lock mechanism, and the operation of releasing the lock is troublesome.

  An object of the present invention is to displace one of a pair of sheet guide portions to a position along a sheet material conveyance path and a position separated from the conveyance path by an intuitive and simple operation. An object of the present invention is to provide a sheet guide mechanism and an image forming apparatus that can easily perform jam processing.

  A sheet guide mechanism according to one aspect of the present invention includes a first sheet guide portion, a second sheet guide portion, and an elastic member. The first sheet guide portion is a portion that is fixed at a predetermined position and demarcates the first side of the sheet material conveyance path. The second sheet guide portion is a portion that defines a second side of the conveyance path. The second sheet guide portion is rotatably supported around a first fulcrum portion at a fixed position, and the guide position facing the first sheet guide portion along the conveyance path is more than the guide position. It is supported so as to be able to rotate between a separated position away from the first sheet guide portion. The connecting member is a member that is rotatably supported around a second fulcrum portion at a fixed position. The connecting member has a slide part slidably connected to a side surface of the second sheet guide part. The elastic member is connected to the side surface of the second sheet guide portion and the connecting member, and expands and contracts according to the rotation of the second sheet guide portion, and the second sheet guide portion is interposed via the connecting member. Apply elastic force to When the second sheet guide portion is present at the guide position, the elastic member exerts an elastic force against a torque in a first rotation direction that rotates the second sheet guide portion toward the separation position. By adding to the second sheet guide portion, the second sheet guide portion is held at the guide position. When the second sheet guide part is present at the separation position, the elastic member exerts an elastic force that resists torque in a second rotation direction opposite to the first rotation direction. In addition, the second sheet guide portion is held at the separation position.

  An image forming apparatus according to another aspect of the present invention includes an image forming unit, a sheet cassette, and the sheet guide mechanism. The image forming unit forms an image on a sheet material. The sheet cassette is a portion that accommodates the sheet material and can be pulled out from the apparatus main body. The sheet guide mechanism is formed along a conveyance path extending in the drawing direction of the sheet cassette above the sheet cassette.

  According to the present invention, one of the pair of sheet guide portions can be displaced to a position along the conveyance path of the sheet material and a position separated from the conveyance path by an intuitive and simple operation. It is possible to provide a sheet guide mechanism and an image forming apparatus that can easily perform jam processing.

FIG. 1 is a configuration diagram of an image forming apparatus according to the first embodiment. FIG. 2 is a perspective view of the upper surface side of the lower sheet guide portion provided in the image forming apparatus according to the first embodiment. FIG. 3 is a perspective view of the lower surface side of the lower sheet guide portion provided in the image forming apparatus according to the first embodiment. FIG. 4 is a side view of the sheet guiding mechanism when the lower sheet guiding portion in the first embodiment exists at the guiding position. FIG. 5 is a side view of the sheet guiding mechanism when the lower sheet guiding portion in the first embodiment exists at the separation position.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In addition, the following embodiment is an example which actualized this invention, Comprising: It does not have the character which limits the technical scope of this invention.

[First Embodiment]
First, the configuration of the image forming apparatus 10 according to the first embodiment will be described with reference to FIG. The image forming apparatus 10 is an electrophotographic image forming apparatus that forms an image on a sheet material 9. The sheet material 9 is a sheet-like image forming medium such as paper, coated paper, postcard, envelope, and OHP sheet.

  The image forming apparatus 10 includes a sheet supply unit 2 below the apparatus main body 100. Further, the image forming apparatus 10 includes a sheet conveying mechanism 3, an image forming unit 4, an optical scanning unit 5, a fixing unit 6, and the like above the sheet supply unit 2 in the apparatus main body 100. The sheet conveyance mechanism 3, the image forming unit 4, the optical scanning unit 5, and the fixing unit 6 are examples of an image forming unit that forms an image on the sheet material 9.

  The sheet supply unit 2 includes a sheet cassette 21 and a sheet delivery unit 22. The sheet cassette 21 is a portion that accommodates the sheet material 9 and can be pulled out from the apparatus main body 100. The sheet sending unit 22 sends the sheet material 9 from the sheet cassette 21 to the first conveyance path 301.

  A first direction D1 shown in each drawing is a direction along the drawing direction of the sheet cassette 21. The second direction D2 is a direction orthogonal to the first direction D1, and is the width direction of the sheet cassette 21. The third direction D3 is a direction perpendicular to the first direction D1 and the second direction D2, and is a vertical direction.

  In the sheet transport mechanism 3, a plurality of rollers such as a first transport roller 31, a second transport roller 32, and a third transport roller 33 transport the sheet material 9. The first conveyance roller 31 conveys the sheet material 9 supplied from the sheet supply unit 2 from the first conveyance path 301 to the second conveyance path 302. The first transport roller 31 is a so-called registration roller.

  The second transport roller 32 transports the sheet material 9 along the second transport path 302 by rotating forward, and further discharges it to the discharge tray 101. The plurality of second transport rollers 32 include a discharge roller 32 a that is positioned at the rearmost stage and discharges the sheet material 9 to the discharge tray 101. The second transport roller 32 rotates in the reverse direction to change the transport direction of the sheet material 9 and transport the sheet material 9 from the second transport path 302 to the third transport path 303.

  When the double-sided printing process is performed, the sheet material 9 on which an image is formed is conveyed along the third conveyance path 303. The double-sided printing process is a process for forming images on both sides of the sheet material 9.

  The third conveyance path 303 is formed to extend in the first direction D1 above the sheet cassette 21 and joins the first conveyance path 301. The third conveyance path 303 is a conveyance path substantially along a horizontal plane.

  The third conveyance roller 33 takes over the conveyance of the sheet material 9 conveyed from the second conveyance path 302 to the third conveyance path 303, and further transfers the sheet material 9 from the third conveyance path 303 to the first conveyance path 301. Transport. The sheet material 9 conveyed from the third conveyance path 303 to the first conveyance path 301 is reversed with respect to the sheet material 9 conveyed from the sheet supply unit 2 to the first conveyance path 301. Thereby, the double-sided printing process can be performed. That is, the third conveyance path 303 is a reverse conveyance path that reverses the front and back of the sheet material 9.

  The image forming unit 4 includes a photoconductor 41, a charging unit 42, a developing unit 43, a transfer unit 45, a cleaning unit 47, and the like. The drum-shaped photoconductor 41 rotates, and the charging unit 42 charges the surface of the photoconductor 41 uniformly.

  The optical scanning unit 5 is a so-called LSU (Laser Scanning Unit). The optical scanning unit 5 writes an electrostatic latent image on the surface of the photoreceptor 41 by scanning with laser light. The developing unit 43 develops the electrostatic latent image with toner. As a result, a toner image is formed on the surface of the photoreceptor 41.

  The transfer unit 45 transfers the toner image on the surface of the photoconductor 41 to the sheet material 9 moving on the first conveyance path 301. The cleaning unit 47 removes the toner remaining on the surface of the photoreceptor 41. The fixing unit 6 heats the sheet material 9 after image formation to fix the toner image on the sheet material 9.

  In the present embodiment, the sheet guide mechanism 1 is provided in the third conveyance path 303. The third conveyance path 303 is an example of a conveyance path that extends along the drawing direction of the sheet cassette 21 above the sheet cassette 21.

  The sheet guide mechanism 1 includes an upper sheet guide portion 11 provided on the upper side of the third conveyance path 303 and a lower sheet guide portion 12 provided on the lower side of the third conveyance path 303. The upper sheet guide portion 11 and the lower sheet guide portion 12 that face each other define an upper side and a lower side of the third conveyance path 303, respectively. In other words, the third conveyance path 303 is formed by the upper sheet guide portion 11 and the lower sheet guide portion 12. The sheet guide mechanism 1 guides the sheet material 9 along the third conveyance path 303. The upper side and the lower side of the third transport path 303 correspond to the first side and the second side of the third transport path 303, respectively.

  The upper sheet guide unit 11 is fixed at a predetermined position on the upper side of the third conveyance path 303 along the third conveyance path 303. For example, the upper sheet guide portion 11 is fixed to the frame of the apparatus main body 100. The lower sheet guide unit 12 is supported on the lower side of the third conveyance path 303 so as to be rotatable between a guide position and a separation position.

  The guide position is a position facing the upper sheet guide portion 11 along the third conveyance path 303. The separation position is a position farther from the upper sheet guide unit 11 than the guide position, and is a position where the third conveyance path 303 is opened. In FIG. 1, the lower sheet guide portion 12 of the guide position is indicated by a virtual line.

  The rotation of the lower sheet guide portion 12 from the guide position to the separation position side is restricted by a restriction portion 211 that is a part of the sheet cassette 21 attached to the apparatus main body 100. That is, the restricting portion 211 is in contact with the lower sheet guide portion 12 from below. Therefore, only when the sheet cassette 21 is pulled out from the apparatus main body 100, the lower sheet guide portion 12 can be rotated from the guide position to the separation position side.

  In a state where the sheet cassette 21 is pulled out from the apparatus main body 100, the user can displace the lower sheet guide portion 12 to the separation position. Thereby, the user can perform jam processing of the third conveyance path 303. The upper sheet guide unit 11 and the lower sheet guide unit 12 are examples of a first sheet guide unit and a second sheet guide unit, respectively.

  By the way, it is conceivable that the sheet guide portion that is rotatably supported like the lower sheet guide portion 12 is held at the guide position along the conveyance path by the elastic force of the spring. In this case, the user must perform the jam processing with one hand.

  That is, the user needs to perform the jam processing with the other hand while holding the sheet guide portion at the separated position with one hand. However, it may be more convenient to use both hands in the jam processing.

  It is also conceivable that the sheet guide mechanism having the rotatable sheet guide part includes a lock mechanism that locks the sheet guide part at the separation position. In this case, the user has to learn an operation of releasing the lock of the lock mechanism, and the operation of releasing the lock is troublesome.

  The sheet guide mechanism 1 in this embodiment is a mechanism that does not require an operation of holding the lower sheet guide portion 12 at the separation position and facilitates the jam processing. Moreover, the seat guide mechanism 1 is a mechanism that does not require locking and unlocking operations, and can displace the lower seat guiding portion 12 between the guide position and the separation position by an intuitive and simple operation. . Hereinafter, the details of the sheet guide mechanism 1 will be described.

[Sheet guide mechanism 1]
2-5, the sheet | seat guide mechanism 1 is provided with the spring 14 and the connection member 15 in addition to the upper sheet | seat guide part 11 and the lower sheet | seat guide part 12. As shown in FIG. The spring 14 is an example of an elastic member that applies an elastic force to the lower sheet guide portion 12. A rubber member or the like may be employed as the elastic member instead of the spring 14.

  4 and 5, the upper sheet guide portion 11 has a structure in which a synthetic base drive roller 331 is combined with a metal base member 110. The drive roller 331 constitutes the third transport roller 33 together with the driven roller 332. The driving roller 331 is a roller that is driven by a motor (not shown), and the driven roller 332 is a roller that rotates following the driving roller 331. Two drive rollers 331 are attached to the base member 110 of the upper sheet guide portion 11 at positions spaced apart in the second direction D2.

  The lower sheet guide portion 12 has a structure in which a metal base member 12x and a synthetic resin addition member 12y are combined. Further, a synthetic resin driven roller 332 and a synthetic resin handle 126 are also combined with the base member 12x. Two driven rollers 332 are attached to the base member 12x of the lower sheet guide portion 12 at positions spaced in the second direction D2.

  The upper surface of the base member 12 x is a guide surface 121 that guides the sheet material 9. The lower sheet guide portion 12 includes a supported portion 122, a spring connecting portion 123, a guide rail portion 124, and the like. In the present embodiment, the supported portion 122 and the spring connecting portion 123 are formed on the base member 12x, and the guide rail portion 124 is formed on the additional member 12y.

  The supported portion 122 is a portion that is supported by the support shaft 19 along the first center line L <b> 1 on the lower side of the third conveyance path 303. The supported portion 122 is formed in a shape that surrounds the support shaft 19 from three directions from above to below. The supported portion 122 has a notch-shaped opening 1220 through which the support shaft 19 can pass.

  The lower sheet guide portion 12 is supported so as to be rotatable around a support shaft 19 at a fixed position. The first center line L <b> 1 is a rotation center line of the lower sheet guide portion 12. In the present embodiment, the support shaft 19 is a part of the apparatus main body 100 or a part supported by the apparatus main body 100. The support shaft 19 is a portion that forms the center of rotation of the lower sheet guide portion 12, and is an example of a first fulcrum portion. It is also conceivable that a shaft portion projects from the lower sheet guide portion 12 and that the shaft portion is rotatably supported by a part of the apparatus main body 100. In this case, the lower sheet guide portion 12 is supported by a part of the apparatus main body 100 so as to be rotatable around the shaft portion. The shaft portion in this case is an example of the first fulcrum portion.

  In the following description, a direction in which the lower sheet guide portion 12 is rotated from the guide position side to the separation position side is referred to as a first rotation direction R1 (see FIGS. 4 and 5). A direction in which the lower sheet guide portion 12 is rotated from the separation position side to the guide position side is referred to as a second rotation direction R2.

  As shown in FIGS. 2 and 3, the handle member 126 is attached to the end portion of the lower sheet guide portion 12. In the lower sheet guide part 12, the end part on the first center line L1 side is a base end part, and the end part on the opposite side is the terminal part. In the present embodiment, the end portion of the lower sheet guide portion 12 is an end portion on the downstream side in the conveyance direction of the sheet material 9.

  The handle member 126 includes a first handle portion 1261 and a second handle portion 1262. The first handle portion 1261 is a portion where an operation of lowering the lower sheet guide portion 12 from the guide position to the separation position is performed. The second handle portion 1262 is a portion where an operation of lifting the lower sheet guide portion 12 from the separation position to the guide position is performed.

  The second handle portion 1262 is formed at a position higher than the first handle portion 1261. Accordingly, at the end portion of the lower sheet guide portion 12 lowered to the separation position, the first handle portion 1261 contacts the upper surface of the table on which the image forming apparatus 10 is placed, and the second handle portion 1262. A space for inserting a finger is secured below the.

  As shown in FIGS. 3 and 4 and the like, in this embodiment, the spring 14 is a tension coil spring. A force for extending the spring 14 acts on the first end 141 and the second end 142 of the spring 14.

  The first end portion 141 of the spring 14 is connected to the spring connecting portion 123 of the lower sheet guide portion 12. The second end 142 of the spring 14 is connected to the connecting member 15.

  The connection member 15 includes a connection base 150, and slide portions 151 and fulcrum portions 152 provided at two locations of the connection base 150. The slide portion 151 is a portion that is slidably connected to the guide rail portion 124 of the lower sheet guide portion 12. The slide portion 151 includes a portion connected to the second end portion 142 of the spring 14. In the present embodiment, the slide portion 151 is formed so as to protrude from the coupling base portion 150 along the second direction D2. Similarly, the fulcrum part 152 is also formed so as to protrude from the connection base part 150 along the second direction D2.

  The supported portion 122, the spring connecting portion 123, and the guide rail portion 124 are provided on the side wall portions that form both side surfaces of the lower sheet guide portion 12. The side wall portions are formed upright from both end portions of the guide surface 121 of the lower sheet guide portion 12. The spring 14 and the connecting member 15 are attached to the side wall portions on both sides of the lower sheet guide portion 12.

  In the example shown in FIG. 3, the shapes of the two connecting members 15 provided on both sides of the lower sheet guide portion 12 are different. The connection base 150 shown in FIGS. 2 and 3 is formed in an arm shape, but the shape of the connection base 150 is arbitrary.

  The guide rail portion 124 is a portion that guides the slide portion 151 of the connecting member 15 along a path extending from the base point portion P1 of the lower sheet guide portion 12 to the end portion side. The guide rail portion 124 is formed along the first direction D1, and the end of the guide rail portion 124 on the spring connecting portion 123 side is a base point portion P1. The base point portion P1 is provided at a position that is spaced from the spring connecting portion 123 in the lower sheet guide portion 12 to the end portion side by a distance larger than the free length of the spring 14.

  For example, the guide rail portion 124 is a portion in which a long hole or groove extending from the base end portion side to the distal end portion side of the lower sheet guide portion 12 is formed. In this case, the slide portion 151 is inserted into the long hole or the groove.

  The fulcrum part 152 of the connecting member 15 is rotatably supported by the bearing part 102 around the second center line L2. The second center line L <b> 2 is a rotation center line of the connecting member 15. The bearing portion 102 is provided at a certain position on the side surface of the apparatus main body 100 that is located on both sides in the width direction of the third conveyance path 303.

  That is, the connecting member 15 is supported so as to be rotatable around the fulcrum portion 152. The second center line L2 is parallel to the first center line L1. The first center line L1 and the second center line L2 are lines along the second direction D2. The fulcrum part 152 is an example of a second fulcrum part.

  In addition, it is also conceivable that a protruding portion that supports the connecting member 15 is formed in a part of the apparatus main body 100, and the connecting member 15 is rotatably supported around the protruding portion. In this case, the connecting member 15 is provided with a hole portion into which the protruding portion is inserted instead of the fulcrum portion 152. The protruding portion is an example of a second fulcrum portion.

  It is also conceivable that the second end 142 of the spring 14 is connected to a part of the connecting member 15 other than the slide part 151 and the fulcrum part 152. For example, it is conceivable that the second end portion 142 is connected to a portion of the connection base 150 that is formed to protrude from a position other than the slide portion 151 and the fulcrum portion 152.

  The spring 14 expands and contracts according to the rotation of the lower sheet guide portion 12 and applies an elastic force to the lower sheet guide portion 12. In the present embodiment, the spring 14 applies an elastic force to the lower sheet guide portion 12 via the slide portion 151 of the connecting member 15.

  As shown in FIGS. 4 and 5, when the lower sheet guide portion 12 is rotated from the guide position to the separation position, the slide portion 151 of the connecting member 15 is moved between the first center line L1 and the second center line L2. It rotates from one side of the plane P0 including the other side.

  In the present embodiment, when the lower sheet guide portion 12 exists at the guide position, the slide portion 151 of the connecting member 15 exists on the upper side of the plane P0 (see FIG. 4). On the other hand, when the lower sheet guide part 12 exists in the said separation position, the slide part 151 of the connection member 15 exists in the lower side of the plane P0 (refer FIG. 5).

  When the lower sheet guide portion 12 is rotated from the guide position in the first rotation direction R1, the slide portion 151 of the connecting member 15 is accordingly moved along the guide rail portion 124 to the end portion side of the lower sheet guide portion 12. Move to. As a result, the spring 14 extends.

  The slide portion 151 passes through the plane P0 from the upper side to the lower side while the lower sheet guide portion 12 is rotating from the guide position to the separation position. On the other hand, when the lower sheet guide part 12 rotates from the separation position in the second rotation direction R2, the slide part 151 returns to the original rotation path.

  When the slide part 151 exists above the plane P0, the elastic force of the spring 14 acts as the first torque T1 for the connecting member 15 (see FIG. 4). The first torque T1 is a torque in a direction in which the slide portion 151 is rotated upward.

  Therefore, when the lower sheet guide portion 12 exists at the guide position, when the lower sheet guide portion 12 receives an external force and tries to rotate in the first rotation direction R1, the elastic force of the spring 14 causes the lower sheet guide portion 12 to rotate. 12 is applied to the lower sheet guide portion 12 as a force against the torque in the first rotation direction R1. Thereby, the spring 14 holds the lower sheet guide portion 12 at the guide position.

  On the other hand, when the slide part 151 exists below the plane P0, the elastic force of the spring 14 acts as the second torque T2 for the connecting member 15 (see FIG. 5). The second torque T2 is a torque in a direction for rotating the slide portion 151 downward.

  Accordingly, when the lower sheet guide portion 12 exists at the separation position, when the lower sheet guide portion 12 receives an external force and tries to rotate in the second rotation direction R2, the elastic force of the spring 14 is reduced. The force is applied to the lower sheet guide portion 12 as a force that resists the torque in the second rotation direction R2 that rotates the lens 12 toward the guide position. Thereby, the spring 14 holds the lower sheet guide portion 12 at the separation position.

  The sheet guide mechanism 1 does not include a lock mechanism that locks the lower sheet guide portion 12 at the guide position and the separation position. The lower sheet guide portion 12 is held at each of the guide position and the separation position by the elastic force of the spring 14. In this case, the lower sheet guide portion 12 is held at each of the separation position and the guide position only by the user lowering the handle member 126 or lifting the handle member 126 upward.

  Therefore, if the seat guide mechanism 1 is adopted, an operation for releasing the lock of the lock mechanism is unnecessary, and the user does not need to learn the operation of the lock mechanism. Further, the user can displace the lower sheet guide portion 12 to the guide position and the separation position by an intuitive and simple operation.

  Furthermore, since the lower sheet guide portion 12 is held at the separation position by the elastic force of the spring 14, the user can perform jam processing on the third conveyance path 303 using both hands.

  Further, in a situation where the lower sheet guide portion 12 is present in the range from the guide position to the separation position, the spring 14 causes the supported portion 122 of the lower sheet guide portion 12 to move from the opposite side of the opening 1220 to the support shaft 19. Apply elastic force in the pressing direction. For this reason, even if the opening 1220 is formed in the supported portion 122, the supported portion 122 does not fall off the support shaft 19. In addition, play between the supported portion 122 and the support shaft 19 is unlikely to occur.

[Application example]
In each embodiment shown above, it is also conceivable that the sheet guide mechanism 1 is provided in a conveyance path along the vertical direction. For example, in the image forming apparatus 10 shown in FIG. 1, it is conceivable that an exterior cover that covers the second conveyance path 302 along the vertical direction is attached to the apparatus main body 100 so as to be openable and closable. In this case, it is conceivable that the sheet guide mechanism 1 is provided in the second conveyance path 302.

  It is also conceivable that the sheet guide mechanism 1 is provided in the conveyance path of the sheet material 9 supplied from the manual feed tray.

  In addition, the sheet guide mechanism 1 may be applied to an image forming apparatus of a system other than the electrophotographic system such as an ink jet image forming apparatus.

  Further, in the sheet guide mechanism 1, a compression coil spring may be employed instead of the spring 14. When the compression coil spring is employed, the spring connecting portion 123 is formed on the end portion side with respect to the guide rail portion 124 in the lower seat guide portion 12.

  The sheet guide mechanism and the image forming apparatus according to the present invention can be freely combined with the above-described embodiments and application examples within the scope of the invention described in each claim, or the embodiments and application examples. It is also possible to configure by appropriately modifying or omitting a part.

DESCRIPTION OF SYMBOLS 1: Sheet guide mechanism 2: Sheet supply part 3: Sheet conveyance mechanism 4: Image forming part 5: Optical scanning part 6: Fixing part 7: Manual feed tray 9: Sheet material 10, 10A: Image forming apparatus 11: Upper sheet guide part (First sheet guide)
12: Lower sheet guide part (second sheet guide part)
12x: Base member of upper sheet guide part 12y: Additional member of upper sheet guide part 14: Spring (elastic member)
15: connecting member 19: support shaft 21: sheet cassette 22, 23: sheet feeding unit 31: first transport roller 32: second transport roller 33: third transport roller 34: fourth transport roller 41: photoconductor 42: charging Part 43: developing part 45: transfer part 47: cleaning part 48: intermediate transfer belt 49: secondary transfer part 100: apparatus main body 101: discharge tray 102: second support shaft 110: base member 121 of upper sheet guide part: lower Guide surface 122 of the sheet guide part: First fulcrum part 123 of the lower sheet guide part: Spring connecting part 124 of the lower sheet guide part: Guide rail part 126 of the lower sheet guide part: Handle member 141: First end part 142 of the spring : Second end portion 151 of the spring: slide portion 152 of the connecting member: second fulcrum portion 211 of the connecting member: regulating portion 301 of the sheet cassette: first conveying path 302 Second transport path 303: Third transport path 304: Fourth transport path 331, 341: Drive rollers 332, 342: Driven roller 480: Secondary cleaning section 1220: Opening 1261: First handle section 1262: Second handle section D1 : First direction D2: second direction D3: third direction L1: first center line L2: second center line P0: plane P1: base point

Claims (5)

A first sheet guide fixed at a predetermined position and defining a first side of a sheet material conveyance path;
A guide position defining the second side of the transport path and supported rotatably around a first fulcrum portion at a fixed position, and facing the first sheet guide section along the transport path and the guide A second sheet guide part rotatably supported between a position separated from the first sheet guide part than the position;
A connecting member having a sliding portion that is rotatably supported around a second fulcrum portion at a fixed position and is slidably connected to a side surface of the second sheet guide portion;
The second sheet guide part is connected to the side surface and the connecting member, expands and contracts according to the rotation of the second sheet guide part, and applies an elastic force to the second sheet guide part via the connecting member. An elastic member,
When the second sheet guide portion exists at the guide position, the elastic member applies an elastic force in a first rotation direction to the connecting member, thereby moving the second sheet guide portion to the guide position. Hold on
When the second sheet guide portion exists at the separation position, the elastic member applies an elastic force in a second rotation direction opposite to the first rotation direction to the connection member, A sheet guide mechanism for holding the second sheet guide portion at the separation position.   The slide portion of the connection member includes a plane including a rotation center line of the second sheet guide portion and a rotation center line of the connection member when the second sheet guide portion is present at the guide position. 2. The sheet guide mechanism according to claim 1, wherein the sheet guide mechanism is positioned above the flat surface when the second sheet guide portion is located at the separation position. The first fulcrum is a fixed spindle;
The supported portion supported by the support shaft in the second sheet guide portion is formed in a shape that surrounds the support shaft from three sides from above to below, and is a notch shape through which the support shaft can pass. Opening is formed,
The sheet guide mechanism according to claim 1, wherein the elastic member applies an elastic force in a direction in which the supported portion of the second sheet guide portion is pressed against the support shaft from the opposite side of the opening. An image forming unit for forming an image on a sheet material;
A sheet cassette that accommodates the sheet material and can be pulled out from the apparatus main body;
An image forming apparatus comprising: the sheet guide mechanism according to claim 1, which is formed along a conveyance path that extends in a drawing direction of the sheet cassette above the sheet cassette.   The image forming apparatus according to claim 4, wherein the conveyance path includes a reverse conveyance path that reverses the front and back of the sheet material.

Images