JP2010117508A - Medium transport apparatus, medium ejecting apparatus and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce damage to a medium after fixing of image. <P>SOLUTION: A medium transport apparatus (Rh+Rb+SH3+SH4+1+GT1, Rh+Rb+SH3+SH4+1'+GT1')is provided with: a medium transporting path (SH3+SH4), having a post fixing transporting path (SH3), a first medium transporting path (SH4a) and a second medium transporting path (SH4b); guiding members (1, 1') on which contact surfaces (1a, 21a, 22b) are formed in planar states: switching guide members (GT1, GT1') on which contact surfaces (2, 3, 26, 27) are formed in plane states; and a medium transport member (Rh+Rb), having a first medium transport member (Rh) that is arranged on the first medium transport path (SH4a) and a second medium transport member (Rb) that is arranged on the second medium transport path (SH4b) for transporting the medium (S) to the downstream side in the medium transport direction. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a medium conveying apparatus, a medium discharging apparatus, and an image forming apparatus.

  2. Description of the Related Art Conventionally, in an image forming apparatus such as an electrophotographic copying machine or printer, an image formed on the surface of a photoreceptor is transferred to a medium, heated and fixed, and then the medium is discharged by a medium discharging apparatus. The techniques described in Patent Literatures 1 to 4 are known.

  Japanese Patent Application Laid-Open No. 2004-109168 as Patent Document 1 discloses a fixing device (117) for heating and fixing a toner image transferred on a recording medium (107), and an in-machine temperature by heating the fixing device (117). An image forming apparatus (100) having an exhaust heat fan (122) for suppressing an increase is described. Patent Document 1 discloses that the exhaust heat fan (in accordance with the measured internal temperature when printing on glossy paper such as an OHP (OverHead Projector) sheet or gloss paper and heat fixing with the fixing device (117). 122), a technique for improving the efficiency of in-machine cooling at the time of discharging the glossy paper by changing the rotational speed of the glossy paper and reducing the occurrence of image unevenness in the printed image after fixing the glossy paper is described. Has been.

Japanese Patent Application Laid-Open No. 2005-128446 as Patent Document 2 is arranged between a discharge roll (41) for discharging a sheet to a storage tray (42) and the storage tray (42), and on the sheet surface. An image forming apparatus (10) having a gloss control device (50) for imparting gloss, so-called gloss, is described. In Patent Document 2, after the image of the sheet is heated and fixed by a fixing device (40) and gloss is applied by the gloss control device (50), a cooling unit (60) of the gloss control device (50) is disclosed. ) Is a technique for cooling by blowing a cooling gas or the like.
Japanese Patent Application Laid-Open No. 2007-298789 as Patent Document 3 discloses a driving roll disposed on the image forming surface side of a discharge roller (Rh) that discharges a recording sheet (S) after being fixed by a fixing device (F). (Rh1) has a plurality of transport rolls (42) arranged at predetermined intervals and having irregularities formed on the surface, and the recording sheet (S) contacts each transport roll (42). A technique for reducing the difference in gloss between a range that has been touched and a range that has not been touched, so-called gloss unevenness, is described.

  Furthermore, Japanese Patent Application Laid-Open No. 2007-271970 as Patent Document 4 discloses a first position for guiding a sheet discharged by a discharge roller (12) to a discharge tray (9), and the sheet for duplex printing. And an image forming apparatus (20) having a flapper (13) as an example of a switching gate movable between a second position guided to the reversing roll (14). In Patent Document 4, when the direction perpendicular to the sheet conveying direction is the width direction, the protrusions formed at both ends in the width direction of the flapper (13) are formed at the four corners of the sheet by heat fixing. A technique for correcting curling, so-called curl, is described.

JP 2004-109168 A (Abstract, “0027” to “0034”, FIGS. 1 to 10) JP 2005-128446 A (abstract, “0008” to “0023”, FIGS. 1 to 8) JP 2007-298789 A (Abstract, “0030” to “0040”, FIGS. 1 to 11) JP 2007-271970 A (Abstract, “0014” to “0026”, FIGS. 1 to 10)

  An object of the present invention is to reduce damage to a medium after image fixing.

In order to solve the technical problem, the medium conveying device of the invention according to claim 1 comprises:
A post-fixing conveyance path disposed on the downstream side in the medium conveyance direction of a fixing device that heat-fixes an image on a medium, and a first medium conveyance path and a second medium conveyance path that branch from the downstream end of the conveyance path in the medium conveyance direction. And a medium conveyance path having
A guide member that guides the medium to the downstream side in the medium transport direction along the post-fixing transport path, the guide member having a flat contact surface that contacts the medium;
A switching guide member that is arranged downstream of the guide member in the medium conveyance direction and switches the medium conveyance direction to the first medium conveyance path or the second medium conveyance path and guides the medium, and contacts the medium The switching guide member having a contact surface formed in a planar shape;
A medium having a first medium conveying member arranged in the first medium conveying path and a second medium conveying member arranged in the second medium conveying path, and conveying the medium downstream in the medium conveying direction A conveying member;
It is provided with.

The invention according to claim 2 is the medium conveying apparatus according to claim 1,
The upstream side in the medium conveyance direction is the switching guide member configured to be rotatable along the medium thickness direction with respect to the downstream end in the medium conveyance direction of the guide member, and the upstream end in the medium conveyance direction of the switching guide member Moves to a position on the upstream side in the medium conveyance direction with respect to the downstream end in the medium conveyance direction of the guide member and on the opposite side of the conveyance path after fixing with the guide member interposed therebetween, thereby guiding the medium to the first conveyance path. The first guide position and the upstream end of the switching guide member in the medium transport direction move to a position opposite to the downstream end of the guide member in the medium transport direction across the post-fixing transport path. The switching guide member that moves between a second guide position that guides two transport paths;
A planar first contact surface that is exposed to the post-fixing conveyance path and guides the medium to the first medium conveyance path when the switching guide member moves to the first guidance position; and the switching guidance member A planar second contact surface that is exposed to the post-fixing conveyance path and guides the medium to the second medium conveyance path when moving to the second guide position;
It is provided with.

The invention according to claim 3 is the medium conveying apparatus according to claim 1 or 2,
The post-fixing conveyance path in which the upstream side in the medium conveyance direction extends upward from the fixing device and the downstream side in the medium conveyance direction is inclined with respect to the direction of gravity;
The guide member formed along the post-fixing conveyance path;
A medium discharge unit disposed on the downstream side in the medium transfer direction of the first medium transfer path and from which the medium is discharged;
When the medium transport direction is switched to the first medium transport path, the upstream end of the switching guide member in the medium transport direction is upstream of the guide member in the medium transport direction and the guide member The switching guide member that is disposed at a position opposite to the post-fixing conveyance path and that guides the medium to the medium discharge section along the first medium conveyance path;
It is provided with.

According to a fourth aspect of the present invention, in the medium conveying apparatus according to the second or third aspect,
A guide-side gear disposed outside the medium in the medium width direction and supported rotatably around a guide-side shaft portion extending in the medium width direction;
A switching side gear supported by the switching guide member and supported by a switching side shaft portion extending from the switching guide member toward the outside in the medium width direction, and meshing with the guide side gear;
A guided portion for switching supported by the switching guide member;
Engage with the switching guided portion and follow the trajectory of the switching guided portion when the switching side gear rotates and moves along the outer periphery of the guide side gear by forward and reverse rotation of the guide side gear. A switching guide unit that guides movement of the switching guide member between the first guide position and the second guide position,
It is provided with.

The invention according to claim 5 is the medium conveying apparatus according to claim 2 or 3,
A guide-side connecting portion as a rotation center that is disposed outside the medium width direction of the medium and supported by a downstream end portion of the guide member in the medium conveyance direction, and supported by an upstream end portion of the switching guide member in the medium conveyance direction. A switching member, and a connecting member that connects the guide member and the switching guide member;
A guided portion for switching supported by a downstream end portion of the switching guide member in a medium conveying direction;
By engaging with the guided part for switching and guiding along the locus of the switching side connecting part when the connecting member rotates by forward and reverse rotation with the guiding side connecting part as a rotation center, A switching guide for guiding the movement of the switching guide member between the first guide position and the second guide position;
It is provided with.

The invention according to claim 6 is the medium conveying apparatus according to claim 2 or 3, wherein
A first guide member that guides the medium along the transport path after fixing to the downstream side in the medium transport direction, the first guide member having a flat contact surface in contact with the medium; and the medium And a contact surface that contacts the medium is formed in a planar shape, and is downstream of the first guide member in the medium conveyance direction, with the upstream end in the medium conveyance direction as the center of rotation. The second guide member, the side of which is rotatably supported, and the guide member,
When the medium is not in contact with the contact surface of the second guide member, the second guide member is held at a neutral position extending along an extension line of the post-fixing conveyance path, and the medium is in contact with the contact surface. A neutral position holding body that permits rotational movement of the second guide member,
It is provided with.

A seventh aspect of the present invention is the medium conveying apparatus according to the sixth aspect,
The switching guide member configured such that the upstream side in the medium conveyance direction is rotatable about the downstream end in the medium conveyance direction, and
When the switching guide member moves from the second guiding position to the first guiding position and the second guiding member is pressed in contact with the switching guiding member, the fixing of the second guiding member is performed. When rotational movement to the opposite side of the rear conveyance path is permitted, and contact between the second guide member and the switching guide member is released before the switching guide member reaches the first guide position. The second guide member is returned to the neutral position, and the second guide member contacts the switch guide member when the switch guide member moves from the first guide position to the second guide position. The second guide member is allowed to rotate to the post-fixing conveyance path side, and before the switching guide member reaches the second guide position, When contact with the switching guide member is released Includes the intermediate position holding member for returning the second guide member to the neutral position,
It is provided with.

In order to solve the technical problem, a medium discharging apparatus according to an eighth aspect of the present invention provides:
A medium discharge unit for discharging the medium;
The medium conveying device according to any one of claims 1 to 7, wherein the medium is discharged to the medium discharging unit;
It is provided with.

In order to solve the technical problem, an image forming apparatus according to claim 9 is provided.
An image recording apparatus for recording an image on a medium;
A fixing device for fixing an image on the surface of the medium;
The medium discharging apparatus according to claim 8, wherein the medium is discharged.
It is provided with.

According to the first, eighth, and ninth aspects of the present invention, damage to the medium after image fixing can be reduced as compared with the case where the configuration of the present invention is not provided.
According to the second aspect of the present invention, the medium guided from the guide member can be guided by the contact surfaces corresponding to the guide positions.
According to the third aspect of the present invention, the heat generated in the fixing device is guided to the medium discharge portion side, and the guide member, the switching guide member, the first medium transport member, and the like are warmed. The temperature difference between the one-medium conveying member and the medium can be reduced, and damage to the image fixed on the medium can be reduced as compared with the case where the configuration of the present invention is not provided.

According to the fourth and fifth aspects of the present invention, the switching guide member does not interfere with the upstream end portion in the medium transport direction of the switching guide member and the downstream end portion in the medium transport direction of the guide member, and the switching guide member is the first guide member. It is possible to move between the guide position and the second guide position.
According to the sixth aspect of the present invention, the medium conveyance resistance received by the medium from the contact surface of the second guide member can be reduced, and the medium is damaged after the image fixing as compared with the case where the structure of the present invention is not provided. Can be reduced.
According to the seventh aspect of the present invention, the switching guide member can push away the second guide member, and the switching guide member can rotate between the first guide position and the second guide position. .

Next, specific examples of embodiments of the present invention (hereinafter referred to as examples) will be described with reference to the drawings, but the present invention is not limited to the following examples.
In order to facilitate understanding of the following description, in the drawings, the front-rear direction is the X-axis direction, the left direction is the Y-axis direction, the up-down direction is the Z-axis direction, and arrows X, -X, Y, -Y, The direction indicated by Z and -Z or the indicated side is defined as the front side, the rear side, the right side, the left side, the upper side, the lower side, or the front side, the rear side, the right side, the left side, the upper side, and the lower side, respectively.
In the figure, “•” in “○” means an arrow heading from the back of the page to the front, and “×” in “○” is the front of the page. It means an arrow pointing from the back to the back.
In the following description using the drawings, illustrations other than members necessary for the description are omitted as appropriate for easy understanding.

FIG. 1 is an overall explanatory view of an image forming apparatus according to Embodiment 1 of the present invention.
In FIG. 1, a printer U as an example of an image forming apparatus according to a first embodiment of the present invention includes an image forming apparatus main body U1. Image information transmitted from the image information transmitting apparatus PC electrically connected to the printer U is input to the control unit C. Image information input to the control unit C is converted into image information of yellow Y, magenta M, cyan C, and black K for forming a latent image at a predetermined time, and is output to the latent image forming device driving circuit DL. .
When the original image is a single color image, so-called monochrome, image information of only black K is input to the latent image forming device driving circuit DL.
The latent image forming device driving circuit DL has driving circuits for respective colors Y, M, C, and K (not shown), and signals corresponding to input image information are arranged for each color at a predetermined time. Output to the image forming apparatuses LHy, LHm, LHc, and LHk.

In FIG. 1, visible image forming devices Uy, Um, Uc, Uk arranged at the center of the gravity direction of the printer U are devices for forming visible images of Y, M, C, K colors, respectively. .
The Y, M, C, and K latent image writing lights emitted from the latent image writing light sources of the latent image forming apparatuses LHy to LHk respectively enter the rotating image carriers PRy, PRm, PRc, and PRk. In the first embodiment, the latent image forming apparatuses LHy to LHk are constituted by so-called LED arrays.
The Y visible image forming device Uy includes a rotating image carrier PRy, a charger CRy, a latent image forming device LHy, a developing device Gy, a primary transfer device T1y, and an image carrier cleaner CLy. In the first exemplary embodiment, the image carrier PRy, the charger CRy, and the image carrier cleaner CLy are configured as an image carrier unit that can be integrally attached to and detached from the image forming apparatus body U1. Has been.
The visible image forming apparatuses Um, Uc, Uk are all configured in the same manner as the Y visible image forming apparatus Uy.

  In FIG. 1, each of the image carriers PRy to PRk is charged by the respective chargers CRy, CRm, CRc, CRk, and then at the image writing positions Q1y, Q1m, Q1c, Q1k by the latent image writing light. An electrostatic latent image is formed on the surface. The electrostatic latent images on the surfaces of the image carriers PRy to PRk are developed in the developing regions Q2y, Q2m, Q2c, and Q2k, as developing rollers GRy, GRm, A toner image as an example of a visible image is developed by the developer held in GRc and GRk.

The developed toner image is conveyed to primary transfer regions Q3y, Q3m, Q3c, and Q3k that are in contact with an intermediate transfer belt B as an example of an intermediate transfer member. In the primary transfer regions Q3y to Q3k, toner is transferred to the primary transfer units T1y, T1m, T1c, and T1k disposed on the back side of the intermediate transfer belt B from the power supply circuit E controlled by the control unit C at a predetermined time. A primary transfer voltage having a polarity opposite to the charging polarity is applied.
The toner images on the image carriers PRy to PRk are primarily transferred to the intermediate transfer belt B by the primary transfer devices T1y to T1k. Residues and deposits on the surface of the image carrier PRy to PRk after the primary transfer are cleaned by image carrier cleaners CLy to CLk. The cleaned surfaces of the image carriers PRy to PRk are recharged by the chargers CRy to CRk.

  Above the image carriers PRy to PRk, a belt module BM as an example of an intermediate transfer device that can move up and down and can be pulled out forward is disposed. The belt module BM includes the intermediate transfer belt B, a belt drive roll Rd as an example of an intermediate transfer body drive member, a tension roll Rt as an example of an intermediate transfer body stretching member, and a walking roll as an example of a meandering prevention member. Rw, an idler roll Rf as an example of a driven member, a backup roll T2a as an example of a secondary transfer region facing member, and the primary transfer units T1y to T1k. The intermediate transfer belt B can be rotated by belt support rolls Rd, Rt, Rw, Rf, T2a as an example of an intermediate transfer member support member constituted by the rolls Rd, Rt, Rw, Rf, T2a. It is supported by.

A secondary transfer roll T2b as an example of a secondary transfer member is disposed facing the surface of the intermediate transfer belt B in contact with the backup roll T2a, and a secondary transfer device T2 is configured by the rolls T2a and T2b. ing. A secondary transfer region Q4 is formed in a region where the secondary transfer roll T2b and the intermediate transfer belt B face each other.
The single-color or multi-color toner images transferred in sequence on the intermediate transfer belt B by the primary transfer units T1y to T1k in the primary transfer areas Q3y to Q3k are conveyed to the secondary transfer area Q4.
The primary transfer units T1y to T1k, the intermediate transfer belt B, the secondary transfer unit T2, and the like constitute a transfer device T1 + T2 + B.

Below the visible image forming apparatuses Uy to Uk, a pair of left and right guide rails GR as an example of a guide member is provided, and the guide rails GR supply paper as an example of a paper feed container. The trays TR1 to TR4 are supported so as to be able to enter and exit in the front-rear direction. The recording sheet S as an example of a medium accommodated in the paper feed trays TR1 to TR4 is an example of a conveying member, and is taken out by a pickup roll Rp as an example of a feeding member, and is separated as an example of a medium spreading member. One by one is separated by Rs. The recording sheet S is conveyed by a plurality of conveyance rolls Ra as an example of a conveyance member along a sheet feeding path SH1 that is an example of a medium conveyance path, and is upstream of the secondary transfer region Q4 in the sheet conveyance direction. The sheet is sent to a registration roll Rr as an example of the arranged transfer region conveyance timing adjustment member.
The pickup roll Rp, the separation roll Rs, and the like constitute a paper feeding device Rp + Rs.
Further, a manual feed tray TR0 as an example of a manual feed unit is installed on the left side of the uppermost sheet feed tray TR1. The recording sheet S supported by the manual feed tray TR0 is fed by a manual feed roll Rp0 as an example of a manual feed member, conveyed through the manual feed path SH0, and sent to the registration roll Rr.

The registration roll Rr adjusts the timing when the toner image formed on the intermediate transfer belt B is conveyed to the secondary transfer region Q4, and moves the recording sheet S downstream of the sheet feeding path SH1 in the medium conveying direction. The recording sheet S is conveyed to the secondary transfer area Q4 by being conveyed to the main conveyance path SH2 as an example of the conveyance path. When the recording sheet S passes through the secondary transfer region Q4, the backup roll T2a is grounded, and the secondary transfer unit T2b is supplied with a polarity opposite to the toner charging polarity from the power supply circuit E controlled by the control unit C. A secondary transfer voltage is applied. At this time, the toner image on the intermediate transfer belt B is transferred to the recording sheet S by the secondary transfer device T2.
The intermediate transfer belt B after the secondary transfer is cleaned by a belt cleaner CLb as an example of an intermediate transfer body cleaner.

The recording sheet S on which the toner image is secondarily transferred has a fixing region Q5 which is a pressure contact region of a heating roll Fh as an example of a heating fixing member of the fixing device F and a pressure roll Fp as an example of a pressure fixing member. And heated and fixed when passing through the fixing region. Note that a release agent for improving the releasability of the recording sheet S from the heating roll is applied to the surface of the heating roll Fh by a release agent coating device Fa.
Here, the image recording devices Uy to Uk + BM + T2 are configured by the visible image forming devices Uy to Uk, the belt module BM, the secondary transfer device T2, and the like.

FIG. 2 is an enlarged explanatory view of a main part of the medium discharging apparatus according to the first embodiment of the present invention.
1 and 2, the fixing device F has a post-fixing conveyance path SH3 that extends obliquely upward to the right as a medium conveyance direction, and a bifurcation from the downstream end of the post-fixing conveyance path SH3 in the medium conveyance direction. A branching medium transport path SH4 is disposed. The branch medium conveyance path SH4 according to the first exemplary embodiment is reverse to a paper discharge path SH4a as an example of a first medium conveyance path that conveys the recording sheet S to a paper discharge tray TRh as an example of a first medium discharge unit. And an upper connection path SH4b as an example of a second medium conveyance path through which the recording sheet S discharged with the image recording surface facing upward is conveyed.

A first gate GT1 as an example of a switching guide member that switches the conveyance path in accordance with the conveyance destination of the recording sheet S is disposed in the branch portion B1 to which the discharge path SH4a and the upper connection path SH4b are connected. Yes. Therefore, when discharged to the paper discharge tray TRh, the fixed recording sheet S is a paper discharge roll Rh as an example of a first medium transport member disposed at the downstream end of the paper discharge path SH4a in the medium transport direction. To be transported.
The post-fixing conveyance path SH3 and the branched medium conveyance path SH4 constitute a medium conveyance path SH3 + SH4.

  1 and 2, an optional discharge unit U3 as an example of an additional medium discharge device is supported above the fixing device F, and the optional discharge unit U3 is disposed above the discharge tray TRh. Similarly to the paper discharge tray TRh, the face down tray TRh2 as an example of the second medium discharge unit stacked with the image recording surface facing downward is stacked with the image recording surface facing upward. A face-up tray TRh3 as an example of a third medium discharge unit.

  Inside the optional discharge unit U3, there is an upper connection roll Rb as an example of a second medium transport member disposed at the downstream end of the upper connection path SH4b in the medium transport direction. Further, on the downstream side in the medium transport direction of the upper connection roll Rb, the reversal / discharge common path SH5 as an example of the transport path connected to the upper connection path SH4, and the reversal / discharge common path SH5 are connected and A face-down discharge path SH6 as an example of a conveyance path for sending the recording sheet S to the face-down tray TRh2, and an example of a conveyance path connected to the reversal / discharge common path SH5 and sending the recording sheet S to the face-up tray TRh3 And a face-up discharge path SH7. In the face-down discharge path SH6, as an example of a second medium discharge member and an example of a medium reversal member, a reversing roll Rh2 capable of rotating in the forward and reverse directions is disposed, and in the face-up discharge path SH7, A face-up paper discharge roll Rh3, which is an example of a third medium discharge member, is disposed and conveys the recording sheet S on each of the conveyance paths SH6 and SH7.

A second gate GT2 as an example of a conveyance path switching member for switching the conveyance path of the recording sheet S is disposed at the branching portion B2 of the reversal / discharge common path SH5, the face-down discharge path SH6, and the face-up discharge path SH7. Yes. The second gate GT2 switches the conveyance path to the face-down discharge path SH6 when the recording sheet S is discharged to the face-down tray TRh2 and reversed for duplex printing, and the recording sheet S is transferred to the face-up tray TRh3. When the paper is discharged, the conveyance path is switched to the face-up discharge path SH7.
A medium transport member Rh + Rb is configured by the paper discharge roll Rh and the upper connection roll Rb.
Here, a second medium discharge path SH4 + SH5 + SH6 is configured by the upper connection path SH4, the reverse / discharge common path SH5, and the face-down discharge path SH6.
The upper connecting path SH4, the reverse / discharge common path SH5, and the face-up discharge path SH7 constitute a third medium discharge path SH4 + SH5 + SH7.

  A reversing unit U4 as an example of an additional unit is installed on the left side of the image forming apparatus main body U1. The reversing unit U4 is provided with a reversing path SH8, which is connected to the lower end of the reversing / discharging common path SH5 and is an example of a transport path for transporting the recording sheet S during duplex printing. The reversing path SH8 includes a main reversing path SH8a extending linearly along the direction of gravity, an upstream reversing path SH8b connecting the main reversing path SH8a and the reversing / discharging common path SH5, and the main reversing path SH8a. And a downstream inversion path SH8c connecting the registration roll Rr. A third gate as an example of a conveyance path switching member that switches the conveyance path so that the recording sheet S is not conveyed to the upper connection path SH4 at the time of reversal is provided at the connection portion B3 between the upstream reversal path SH8b and the reversal / discharge common path SH5. GT3 is arranged. A reversing path as an example of a reversing path transporting member that transports the recording sheet S in the reversing path SH8 is provided on the reversing path SH8 that is a transport path downstream in the transport direction of the reversing / discharging common path SH5 and the face-down discharging path SH6. A transport roll Ra2 is disposed.

Therefore, the recording sheet S to be printed on both sides is conveyed through the reversing / discharging common path SH5 and discharged to the face-down tray TRh2 until the rear end portion of the recording sheet S is sandwiched by the reversing roll Rh2. After that, the reverse roll Rh2 rotates in the reverse direction, and the recording sheet S is conveyed to the reverse path SH8. The recording sheet S transported through the reversing path SH8 is transported by the reversing path transport roll Ra2, and is transported to the registration roll Rr with the front and back sides reversed.
In FIG. 1, the paper feed path SH1 includes, as an example of a medium detection member, a first paper feed path sensor SN1 and a second paper feed path for detecting a recording sheet S fed from each of the paper feed trays TR1 to TR4. A paper path sensor SN2, a third paper path sensor SN3, and a fourth paper path sensor SN4 are arranged. The upper connection path SH4, the reversal / discharge common path SH5, the main reversal path SH8a, and the discharge paths SH3, SH6, SH7 also include a plurality of sensors (not shown) for detecting the recording sheet S as an example of the medium detection member. Is arranged.

In FIG. 1, in the first embodiment, a lower cover U1a as an example of an upstream opening member is located on the left side of the lower three-stage sheet feeding trays TR2 to TR4, and a normal position indicated by a solid line in FIG. 1 is supported so as to be openable and closable with respect to an open position indicated by a broken line in FIG. The lower cover U1a supports a left side guide of the paper feed path SH1 on the left side of the paper feed trays TR2 to TR4, a so-called guide, and the outside of the pair of transport rolls Ra. Therefore, by moving the lower cover U1a to the open position, the lower portion of the paper feed path SH1, that is, the upstream paper feed path SH1a on the upstream side in the transport direction is opened.
In FIG. 1, the reversing unit U4 includes, as an example of a downstream opening member, on the left side of the main reversing path SH8a, between a normal position indicated by a solid line in FIG. 1 and an open position indicated by a broken line in FIG. An inversion path opening cover U4a supported so as to be openable and closable is disposed. The reversing path opening cover U4a supports a left guide of the main reversing path SH8a, and the main reversing path SH8a is opened by moving the reversing path opening cover U4a to the open position.

  Above the belt module BM, developer cartridges Ky, Km, Kc, and Kk, which are examples of developer supply containers that store yellow Y, magenta M, cyan C, and black K developers, are disposed. The developers contained in the developer cartridges Ky, Km, Kc, and Kk are supplied from the developer supply path (not shown) to the developing devices Gy according to the consumption of the developer in the developing devices Gy, Gm, Gc, and Gk. , Gm, Gc, Gk. In Example 1, the developer is composed of a two-component developer including a magnetic carrier and a toner provided with an external additive.

(Description of the guide member 1 and the first gate GT1 of the first embodiment)
3 is an enlarged explanatory view of a main part of the guide member and the first gate according to the first embodiment of the present invention, FIG. 3A is a perspective explanatory view of the first gate, and FIG. 3B is the first gate at the first guide position. FIG. 3C is an explanatory diagram of a state in which the first gate has moved from the state of FIG. 3A to the second guide position.
2 and 3, a guide as an example of a guide member that guides the recording sheet S to the downstream side in the medium transport direction along the post-fixing transport path SH3 in the post-fixing transport path SH3 according to the first exemplary embodiment. The member 1 is supported. The guide member 1 according to the first embodiment is formed in a flat plate shape, and a guide lower surface 1a as an example of a flat contact surface that contacts the recording sheet S is formed on the lower surface of the guide member 1. . A pair of front and rear guide-side shaft portions 1b and 1b extending outward in the medium width direction from the downstream end portion in the medium transport direction are supported on both end faces in the front-rear direction as the medium width direction of the guide member 1. Guide side idler gears 1c and 1c, which are examples of guide side gears, are rotatably supported on the guide side shaft portions 1b and 1b.

  In FIG. 3, the first gate GT <b> 1 of the first embodiment is formed in a flat plate shape, and the lower surface of the first gate GT <b> 1 is an example of a flat first contact surface that contacts the recording sheet S. The gate lower surface 2 is formed, and the gate upper surface 3 as an example of the second contact surface is formed on the upper surface of the first gate GT1. Further, on both end faces in the front-rear direction of the first gate GT1, there are first switching-side shaft portions 4, 4 as an example of a switching-side shaft portion extending outward in the medium width direction from the upstream end portion in the medium transport direction, and the medium Second switching side shaft portions 6 and 6 as an example of a switching guided portion that extends outward from the downstream end portion in the transport direction in the medium width direction are supported. Switching side gears 7 and 7 as an example of switching side gears are fixedly supported on the first switching side shaft portions 4 and 4, and the switching side gears 7 and 7 are connected to the guide side idler gears 1c and 1c. I'm engaged.

In FIG. 2, a frame body of the image forming apparatus main body U1, that is, a so-called front frame U1b and a rear frame U1c are arranged on both the front and rear sides of the guide member 1 and the first gate GT1. In each of the frames U1b, U1c, guide side shaft support holes 8, 8 are formed at positions corresponding to the guide member 1. The guide side shaft portions 1b, 1b of the guide member 1 are penetrated and supported in the guide side shaft portion support holes 8, 8. That is, the guide member 1 is supported by the frames U1b and U1c via the guide-side shaft portions 1b and 1b.
A switching drive motor 11 as an example of a switching drive member is supported on the rear frame U1c adjacent to the left side of the guide side shaft support hole 8 on the rear side. The switching drive motor 11 supports a drive side gear 12 to which the rotation of the switching drive motor 11 is transmitted, and the drive side gear 12 meshes with the rear guide side idler gear 1c. .

An elastic member for pulling the first switching side shafts 4 and 4 toward the guide side shafts 1b and 1b is provided between the first switching side shafts 4 and 4 and the guide side shafts 1b and 1b. As an example, tension springs 13 and 13 are connected.
Each of the frames U1b and U1c is formed with switching guide holes 14 and 14 as an example of a switching guide portion that extends along a paper discharge path SH4a from a position corresponding to the first gate GT1. The second switching side shafts 6 and 6 are passed through the switching guide holes 14 and 14. That is, the first gate GT1 according to the first embodiment is engaged with the switching guide holes 14 and 14 by the second switching side shaft portions 6 and 6, and is supported so as to be movable along the paper discharge path SH4a. Yes.

  In the first embodiment, when the rear guide-side idler gear 1c is rotated through the drive-side gear 12 by the rotational drive of the switching drive motor 11, the switching-side gears 7 and 7 constituted by so-called planetary gears are used. However, it rotates on the outer peripheral surfaces of the guide side gears 1c, 1c. For this reason, the upstream end of the first gate GT1 in the medium conveyance direction rotates and moves along the outer periphery of the guide side gears 1c and 1c via the first switching side shafts 4 and 4. At this time, the upstream end of the first gate GT1 in the medium conveyance direction moves along the paper discharge path SH4a via the second switching side shafts 6 and 6.

  Here, in the first embodiment, when the switching drive motor 11 rotates in the forward direction, the first gate GT1 is configured such that the upstream end of the first gate GT1 in the medium conveyance direction is the guide member 1 as shown in FIG. 3B. Is set in advance so as to move to a first guide position that is a position disposed on the opposite side of the post-fixing conveyance path SH3 across the downstream end in the medium conveyance direction. When the switching drive motor 11 rotates in the reverse direction, the first gate GT1 has an upstream end in the medium transport direction of the first gate GT1 at a downstream end in the medium transport direction of the guide member 1, as shown in FIG. 3C. On the other hand, it is set in advance so as to move to a second guide position that is a position disposed on the opposite side across the post-fixing conveyance path SH3. Therefore, the upstream side of the first gate GT1 in the medium conveyance direction can rotate and move along the medium thickness direction with respect to the downstream end of the fixedly supported guide member 1 in the medium conveyance direction.

In the first embodiment, the movement of the first gate GT1 between the first guide position and the second guide position is controlled by a preset forward / reverse rotation amount of the switching drive motor 11. Yes. The first gate GT1 is normally disposed at the first guide position, and moves from the first guide position to the second guide position when the recording sheet S is conveyed to the upper connection path SH4b. After the recording sheet S is discharged, it quickly returns to the first guide position.
The medium transport device Rh + Rb + SH3 + SH4 + 1 + GT1 is configured by the medium transport member Rh + Rb, the medium transport path SH3 + SH4, the guide member 1, the first gate GT1, and the like.
The medium transport device RHS + Rb + SH3 + SH4 + 1 + GT1, the paper discharge tray TRh, the optional discharge unit U3, and the like constitute the medium discharge device BHS of the first embodiment.

(Operation of Example 1)
In the printer U according to the first embodiment having the above-described configuration, when an image forming operation, so-called job, is executed, an image is recorded on the recording sheet S by the image recording devices Uy to Uk + BM + T2, and the fixing device F Then, the image is fixed on the surface of the recording sheet S and conveyed to the post-fixing medium conveyance path SH3.
At this time, the first gate GT1 is disposed at the first guide position shown in FIG. 3B. Therefore, when the recording sheet S is discharged to the discharge tray TRh, the first gate GT1 is held at the first guide position. Accordingly, since the upstream end in the medium conveyance direction of the first gate GT1 is disposed on the opposite side of the post-fixing conveyance path SH3 with the guide member 1 interposed therebetween, the recording sheet S conveyed from the guide member 1 is moved to the first gate GT1. The paper is guided to the paper discharge path SH4a without being caught at the upstream end in the medium conveyance direction.

At this time, the recording sheet S comes into contact with the guide lower surface 1a of the guide member 1 exposed in the post-fixing conveyance path SH3 and is guided to the discharge path SH4a, and then exposed to the discharge path SH4a. It contacts the lower surface 2 of the gate GT1 and is guided to the paper discharge tray TRh.
Since the recording sheet S is in contact with the guide lower surface 1a extending obliquely upward to the right in accordance with the post-fixing conveyance path SH3 from the upper side, the lower surface side is easily bent. For this reason, the discharged recording sheet S is easier to stack due to improved accommodation on the paper discharge tray TRh compared to the case where the upper surface is bent.

  When the recording sheet S is conveyed to the upper connection path SH4b, the first gate GT1 moves from the first guide position to the second guide position shown in FIG. 3C. At this time, after the recording sheet S comes into contact with the guide lower surface 1a and is guided by the first gate GT1, the recording sheet S comes into contact with the gate upper surface 3 of the first gate GT1 exposed on the upper connection path SH4b side and contacts the upper connection roll. Guided by Rb. Therefore, the upstream end in the medium transport direction of the first gate GT1 is disposed on the opposite side of the downstream end in the medium transport direction of the guide member 1 with the post-fixing transport path SH3 interposed therebetween, and therefore the recording sheet guided from the guide member 1 S is guided to the upper connection path SH4b without being caught by the upstream end of the first gate GT1 in the medium conveyance direction.

FIG. 4 is a diagram for explaining the operation of the first embodiment, and is a diagram for explaining a conventionally known guide member and a recording sheet in contact with the first gate. FIG. 4A shows the first gate corresponding to FIG. 4B is an explanatory view of the guide member and the first gate as viewed from the line IVB of FIG. 4A, and FIG. 4C is a sectional view taken along the line IVC-IVC of FIG. 4A.
Here, in the conventionally known guide member 01 and first gate 02 shown in FIG. 4A, as shown in FIG. 4B, the upstream end portion of the first gate 02 in the medium transport direction and the downstream end portion of the guide member 01 in the medium transport direction. Are generally formed in a comb-teeth shape, and the recording sheet S is not caught in a region where the guide member 01 and the first gate 02 are engaged with each other by arranging the teeth in a state in which the comb teeth are engaged with each other. It is delivered and continuously guided.

  In this case, as shown in FIG. 4C, in the region where the comb-shaped first gate 02 and the guide member 01 mesh with each other, the comb teeth are arranged in a wavy manner on the surface of the recording sheet S. . Therefore, in this region, when the first gate 02 or the guide member 01 comes into contact with the upper surface as the contact surface of the recording sheet S, the contact area of the upper surface is damaged, or damage such as a crease is formed. Could occur. In particular, as in Patent Documents 1 to 3, when gloss is applied to the recording sheet S, gloss unevenness may occur due to damage to the contact surface of the recording sheet S. Further, when a flapper (13) for removing curl is provided as in the technique described in Patent Document 4, contact between the flapper (13) and the recording sheet S may cause damage to the contact surface of the recording sheet S. was there.

  On the other hand, in the printer U according to the first embodiment, the contact surfaces 1a, 2 and 3 where the guide member 1 and the first gate GT1 come into contact with the recording sheet S are formed in a planar shape. For this reason, compared with the conventionally known guide member and the first gate that are partially in contact with the contact surface of the recording sheet S, the contact range of the upper surface is partially damaged or broken, for example. Reduced. Also, when gloss is applied to the recording sheet S, gloss unevenness is reduced as compared with a conventionally known image forming apparatus.

In the printer U according to the first exemplary embodiment, as illustrated in FIGS. 2 and 3B, the first gate GT <b> 1 is normally disposed at the first guide position as illustrated in FIG. 2 and FIG. It is covered with the first gate GT1. Therefore, in the printer U according to the first embodiment, heat generated by the fixing device F is guided by the guide member 1 and the first gate GT1 and discharged by the paper discharge tray TRh as compared with the conventionally known image forming apparatus. It is easy to be done.
Here, for example, in a configuration in which heat is not guided to the paper discharge tray TRh, when gloss is applied to the recording sheet S, the contact surface with the paper discharge roll Rh when contacting the low temperature paper discharge roll Rh. Is cooled rapidly. For this reason, when the temperature difference between the recording sheet S and the paper discharge roll Rh is large, the difference in image gloss between the range in contact with the paper discharge roll Rh and the range not in contact, that is, There was a high possibility that gross unevenness would occur.

However, in the printer U according to the first embodiment, the discharge roll Rh, the first gate GT, the guide member 1 and the like are warmed by the heat guided to the discharge tray TRh, and the recording roll Rh and the recording are recorded. The temperature difference with the sheet S is small. For this reason, in the printer U according to the first exemplary embodiment, the contact surface with the paper discharge roll Rh is less rapidly cooled than the conventionally known image forming apparatus, and the occurrence of gloss unevenness is reduced. .
Further, in the printer U according to the first embodiment, on the side of the upper connection path SH4b, the guide member 1 and the first gate GT1 prevent the heat from rising, so that the low temperature portion made of metal or the like is condensed. Is reduced.

Next, the second embodiment of the present invention will be described. In the description of the second embodiment, the same reference numerals are given to the components corresponding to the components of the first embodiment, and the detailed description thereof will be given. Omitted.
The second embodiment is different from the first embodiment in the following points, but is configured in the same manner as the first embodiment in other points.

(Description of the guide member 1 and the first gate GT1 of the second embodiment)
FIG. 5 is an enlarged explanatory view of the main part of the guide member and the first gate of the second embodiment of the present invention corresponding to FIG. 3 of the first embodiment, and FIG. 5A is a state in which the first gate is moved to the first guide position. FIG. 5B is an explanatory diagram of a state in which the first gate has moved from the state of FIG. 5A to the second guide position.
In FIG. 5, the switching drive motor 11, the drive side gear 12, and the tension springs 13 and 13 are omitted from the configuration of the first embodiment in the printer U of the second embodiment. Further, between the guide side shaft portions 1b, 1b of the guide member 1 and the first switching side shaft portions 4, 4 of the first gate GT1, the guide side idler gears 1c, 1c and the switching side gear 7, of the first embodiment, Instead of 7, L-shaped links 16, 16 as an example of a connecting member for connecting the guide member 1 and the first gate GT1 are connected.

6 is an enlarged explanatory view of a main part of the electromagnetic solenoid according to the second embodiment of the present invention, and is a cross-sectional view taken along line VI-VI in FIG. 5B.
Guide-side connecting portions 16a and 16a as rotation centers connected to the guide-side shaft portions 1b and 1b are arranged at the central portions of the links 16 and 16 of the second embodiment, and the right ends of the links 16 and 16 are arranged. The switching side connecting portions 16b and 16b connected to the first switching side shaft portions 4 and 4 are disposed in the portion. 5 and 6, main body side connecting portions 16c and 16c are formed at the left end portion of the rear link 16, and the main body side connecting portions 16c and 16c are arranged from the left end portion to the central portion side. Long holes 16d, 16d extending are formed.
In addition, as an example of an elastic member that pulls the left end of the links 16 and 16 downward between the left end of the links 16 and 16 and the elastic member supports U1b1 and U1c1 protruding inward from the frames U1b and U1c. Tension springs 17 and 17 are connected.
Further, above the long holes 16d, 16d, electromagnetic solenoids 18, 18 as an example of elevating members connected to the long holes 16d, 16d are supported by the rear frame U3c.

5 and 6, the electromagnetic solenoids 18 and 18 of the second embodiment correspond to the operation of an electromagnetic solenoid body 18a as an example of a lifting member body and an electromagnet (not shown) housed in the electromagnetic solenoid bodies 18a and 18a. And plungers 18b and 18b as an example of movable cores that can move in the protruding and retracting direction. Further, link connecting portions 18c and 18c as an example of a claw-like connecting portion are formed at the lower end portions of the plungers 18b and 18b, and the link connecting portions 18c and 18c have the long holes 16d and 16d. It penetrates and is connected to the links 16, 16.
Further, each frame U1b, U1c of the second embodiment extends in an arc shape along the rotation direction of the guide side connecting portions 16a, 16a, instead of the switching guide holes 14, 14 of the first embodiment, and Switching guide holes 14 ′ and 14 ′ through which the second switching side shaft portions 6 and 6 pass are formed.

In the second embodiment, as shown in FIG. 5A, when the electromagnetic solenoids 18 and 18 are not operated, the left end portions of the links 16 and 16 are pulled downward by the tension springs 17 and 17. Accordingly, the links 16 and 16 receive a force that rotates in the direction in which the main body side connecting portions 16c and 16c move downward about the guide side connecting portions 16a and 16a, as shown in FIG. The upstream end of the one gate GT1 in the medium transport direction is held at the first guide position that has moved upward from the downstream end of the guide member 1 in the medium transport direction.
Further, as shown in FIG. 5B, when the electromagnetic solenoids 18 and 18 are operated, the plungers 18b and 18b of the electromagnetic solenoid 18 resist the tension of the elastic springs 17 and 17 and the electromagnetic solenoid body 18a on the upper side. , 18a side. Therefore, the links 16 and 16 receive a force of rotating in the direction of the arrow Ya in which the main body side connecting portions 16c and 16c move upward with the guide side connecting portions 16a and 16a as the rotation center. Therefore, the second switching side shafts 6 and 6 of the first gate GT1 are guided along the switching guide holes 14 'and 14', and as shown in FIG. 5B, the upstream end of the first gate GT1 in the medium transport direction. Moves to the second guide position moved downward from the downstream end of the guide member 1 in the medium conveying direction.

(Operation of Example 2)
In the printer U of the second embodiment having the above-described configuration, when a job is executed, an image is recorded on the recording sheet S by the image recording apparatuses Uy to Uk + BM + T2, and the image is recorded on the surface of the recording sheet S by the fixing apparatus F. The image is fixed and conveyed to the post-fixing medium conveyance path SH3.
At this time, the first gate GT1 is disposed at the first guide position shown in FIG. 5A by the links 16 and 16 and the tension springs 17 and 17, and the recording sheet S is discharged to the discharge tray TRh. The first gate GT1 is held at the first guide position. The recording sheet S conveyed to the guide member 1 contacts the guide lower surface 1a of the guide member 1 exposed on the post-fixing conveyance path SH3 and is guided to the paper discharge path SH4a, and then exposed to the paper discharge path SH4a. The first gate GT1 is brought into contact with the gate lower surface 2 and guided to the paper discharge tray TRh.

  When the recording sheet S is conveyed to the upper connection path SH4b, the first gate GT1 is moved from the first guide position to the second guide position shown in FIG. 5B by the links 16, 16 and the electromagnetic solenoids 18, 18. Move to. At this time, after the recording sheet S comes into contact with the guide lower surface 1a and is guided by the first gate GT1, the recording sheet S comes into contact with the gate upper surface 3 of the first gate GT1 exposed on the upper connection path SH4b side and contacts the upper connection roll. Guided by Rb.

Here, in the printer U according to the second embodiment, as in the printer U according to the first embodiment, the contact surfaces 1a, 2, and 3 where the guide member 1 and the first gate GT1 are in contact with the recording sheet S are provided. It is formed in a planar shape. As a result, compared with the conventionally known guide member and the first gate that are partially in contact with the contact surface of the recording sheet S, the contact range of the upper surface is partially damaged or creased. Reduced. Also, when gloss is applied to the recording sheet S, gloss unevenness is reduced as compared with a conventionally known image forming apparatus.
In addition, the printer U according to the second embodiment has the same effects as the printer U according to the first embodiment.

Next, the third embodiment of the present invention will be described. In the description of the third embodiment, the same reference numerals are given to the components corresponding to the components of the first embodiment, and the detailed description thereof will be given. Omitted.
The third embodiment is different from the first embodiment in the following points, but is configured in the same manner as the first embodiment in other points.

(Description of the guide member 1 'and the first gate GT1 of the third embodiment)
FIG. 7 is an enlarged explanatory view of the main part of the guide member and the first gate of the third embodiment of the present invention corresponding to FIG. 3 of the first embodiment, and FIG. 7A is a state in which the first gate is moved to the first guide position. FIG. 7B is an explanatory diagram of a state in which the first gate has moved to the second guide position from the state of FIG. 7A, and FIG. 7C is an explanatory diagram of a state in which the second guide member is disposed at the neutral position. is there.
In FIG. 7, the switching drive motor 11, the drive side gear 12, and the tension springs 13 and 13 are omitted from the configuration of the first embodiment in the printer U of the third embodiment. The printer U according to the third embodiment includes a guide member 1 ′ that guides the recording sheet S to the first gate GT1 along the post-fixing conveyance path SH3, instead of the guide member 1 according to the first embodiment.

  The guide member 1 ′ according to the third exemplary embodiment includes a guide member main body 21 as an example of a first guide member disposed on the upstream side in the medium conveyance direction, and the guide member main body 21 disposed on the downstream side in the medium conveyance direction. And a movable guide member 22 as an example of a second guide member. The guide member body 21 is supported by the frames U1b and U1c, and a first guide lower surface 21a as an example of a planar contact surface that contacts the recording sheet S is provided on the lower surface of the guide member body 21. Is formed. Further, the movable guide member 22 according to the third embodiment is supported at the downstream end of the guide member main body 21 in the medium conveyance direction so as to be rotatable about the rotation shaft 22a, and on the lower surface of the movable guide member 22. Is formed with a second guide lower surface 22b as an example of a flat contact surface that contacts the recording sheet S.

  Further, a neutral position holder that pulls the movable guide member 22 toward the guide member main body 21 between the downstream end of the guide member main body 21 in the medium conveyance direction and the upstream end of the movable guide member 22 in the medium conveyance direction. As an example, a tension spring 23 is connected. As shown in FIG. 7C, the tension spring 23 according to the third embodiment is set in advance so as to hold the movable guide member 22 in a neutral position that is arranged along the post-fixing conveyance path SH3. . In Example 3, as shown in FIGS. 7A and 7B, when the recording sheet S guided from diagonally lower left contacts the second guide lower surface 22 b of the movable guide member 22, the movable guide member 22. The urging force of the tension spring 23 is set so that is pushed away from the neutral position and rotates.

  The printer U according to the third embodiment is provided with a first gate GT1 ′ as an example of a switching guide member that switches the conveyance path according to the conveyance destination of the recording sheet S, instead of the first gate GT1 according to the first embodiment. Has been. The first gate GT1 'according to the third embodiment is formed in a flat plate shape, and is supported by the frames U1b and U1c so as to be rotatable about the rotation shaft 24 at the downstream end portion in the medium transport direction. A gate lower surface 26 as an example of a planar first contact surface that contacts the recording sheet S is formed on the lower surface of the first gate GT1 ', and a second contact surface is formed on the upper surface of the first gate GT1. As an example, a gate upper surface 27 is formed.

A switching side gear 28 as an example of a switching side gear is fixed to the rotating shaft 24 of the third embodiment, and the switching side gear 28 is switched via a drive gear 29 as an example of a rotation transmission system. This is connected to a switching drive motor 31 as an example of the drive member for use.
Therefore, in the third embodiment, as shown in FIG. 7A, due to the meshing of the gears 28 and 29, the upstream end in the medium transport direction of the first gate GT1 is more than the downstream end in the medium transport direction of the guide member 1 at normal times. The first guide position moved upward is held.
7A, when the switching drive motor 31 is rotated forward, the rotary shaft 24 is rotated forward via the gears 28 and 29. Therefore, the upstream end of the first gate GT1 in the medium conveyance direction rotates about the rotation shaft 24 in the arrow Yb direction on the post-fixing conveyance path SH3 side, and the movable guide member 22 disposed at the neutral position. The upstream end of the gate lower surface 26 in the medium conveyance direction comes into contact.

Further, when the switching drive motor 31 is further rotated forward, the first gate GT1 further rotates in the direction of the arrow Yb with the rotation shaft 24 as the rotation center, and the downstream end portion of the movable guide member 22 in the medium transport direction is the first. 1 gate GT1 is pressed by the upstream end of the medium conveyance direction, and rotates in the direction of arrow Yb with the rotation shaft 22a as the rotation center. When the switching drive motor is further rotated forward, the contact between the first gate GT1 and the movable guide member 22 is released, the movable guide member 22 returns to the neutral position, and the first gate GT1 is The second guide position shown in 7B is reached.
7B, when the switching drive motor is rotated in the reverse direction, the upstream end of the first gate GT1 in the medium conveyance direction has an arrow on the opposite side of the post-fixing conveyance path SH3 with the rotation shaft 24 as the rotation center. Rotate and move in the Yc direction. Therefore, the movable guide member 22 disposed at the neutral position and the gate upper surface 27 come into contact with each other, and the first gate GT1 and the movable guide member 22 rotate and move in the direction of the arrow Yc on the opposite side of the post-fixing conveyance path SH3. To do. When the switching drive motor is further rotated in the reverse direction, the contact between the first gate GT1 and the movable guide member 22 is released, the movable guide member 22 returns to the neutral position, and the first gate GT1 is Return to the first guide position shown in 7A.

The medium conveying device Rh + Rb + SH3 + SH4 + 1 ′ + GT1 ′ of the second embodiment is configured by the medium conveying member Rh + Rb, the medium conveying path SH3 + SH4, the guide member 1 ′, the first gate GT1 ′, and the like.
The medium transport device RHS + Rb + SH3 + SH4 + 1 ′ + GT1 ′, the paper discharge tray TRh, the optional discharge unit U3, and the like constitute the medium discharge device BHS ′ of the second embodiment.

(Operation of Example 3)
In the printer U of the third embodiment having the above-described configuration, when a job is executed, an image is recorded on the recording sheet S by the image recording apparatuses Uy to Uk + BM + T2, and the image is recorded on the surface of the recording sheet S by the fixing apparatus F. The image is fixed and conveyed to the post-fixing medium conveyance path SH3.
At this time, the first gate GT1 ′ is disposed at the first guide position shown in FIG. 7A, and the recording sheet S conveyed to the guide member main body 21 of the guide member 1 ′ moves to the post-fixing conveyance path SH3. The exposed first guide lower surface 21a, the second guide lower surface 22b of the movable guide member 27, and the gate lower surface 26 of the first gate GT1 ′ are brought into contact with and guided to the paper discharge tray TRh.
When the recording sheet S is conveyed to the upper connection path SH4b, the recording drive motor 31 moves from the first guide position to the second guide position shown in FIG. At this time, the recording sheet S comes into contact with the guide lower surfaces 21a and 22b and the gate upper surface 27 of the first gate GT1 'and is guided to the upper connection roll Rb.

  Here, in the printer U of the third embodiment, as in the printer U of the first and second embodiments, the contact surfaces 21a, the guide member 1 'and the first gate GT1' contact the recording sheet S. 22b, 26, and 27 are formed in a planar shape. As a result, compared with the conventionally known guide member and the first gate that are partially in contact with the contact surface of the recording sheet S, the contact range of the upper surface is partially damaged or creased. Reduced. Also, when gloss is applied to the recording sheet S, gloss unevenness is reduced as compared with a conventionally known image forming apparatus.

Further, in the printer U according to the third embodiment, the movable guide member 22 is moved from the post-fixing conveyance path SH3 from the neutral position shown in FIG. 7C by the pressing force when the recording sheet S comes into contact with the second guide lower surface 22b from below. It moves so as to be pushed away upward. For this reason, in the printer U according to the third embodiment, when the recording sheet S comes into contact, the movable guide member 22 is not pushed away from the neutral position. Thus, the medium conveyance resistance is reduced, and the contact surface of the recording sheet S is reduced. Is less damaged. In particular, when the recording sheet S is conveyed to the upper connection path SH4b, the movable guide member 22 is pushed upward from the neutral position, the medium conveyance resistance with respect to the recording sheet S is reduced, and the recording sheet S is moved upward. It is easy to be guided to the upper connection path SH4b.
In addition, the printer U according to the third embodiment has the same effects as the printer U according to the first and second embodiments.

(Example of change)
As mentioned above, although the Example of this invention was explained in full detail, this invention is not limited to the said Example, A various change is made in the range of the summary of this invention described in the claim. Is possible. Modification examples (H01) to (H04) of the present invention are exemplified below.
(H01) In the above-described embodiment, the printer is illustrated as an example of the printer U. However, the present invention is not limited to this, and the present invention can be applied to a copying machine, a FAX, or a multifunction machine having a plurality of functions. Further, the image forming apparatus is not limited to an electrophotographic image forming apparatus, and can be applied to an image forming apparatus of an arbitrary image forming system such as an ink jet recording system, a thermal head system, or a printing machine such as a lithograph. Further, the image forming apparatus is not limited to a multi-color developing image forming apparatus, and may be configured by a monochromatic, so-called monochrome image forming apparatus.

(H02) As in the above-described embodiment, the upper portion of the fixing device F is covered with the guide members 1 and 1 ′ and the first gates GT1 and GT1 ′, and the heat at the time of heat fixing of the fixing device F is the discharge tray TRh. However, the present invention is not limited to this, and the guide members 1, 1 ′ and the first gates GT 1, GT 1 ′ may be arranged so as not to block the fixing device F.
(H03) As in the above-described embodiment, in order to improve the accommodation on the paper discharge tray TRh, the guide members 1 and 1 'extend obliquely upward to the right and are arranged along the post-fixing conveyance path SH3. Although it is preferable, the present invention is not limited to this, and the medium conveyance direction by the guide members 1 and 1 ′ can be set to an arbitrary direction.
(H04) In the second embodiment, the guide member 1 ′ is constituted by the guide member main body 21 and the movable guide member 22. However, the present invention is not limited to this. For example, a movable guide member similar to the movable guide member 22 is used as the medium. It is also possible to adopt a configuration in which a plurality of them are connected downstream in the transport direction.

FIG. 1 is an overall explanatory view of an image forming apparatus according to Embodiment 1 of the present invention. FIG. 2 is an enlarged explanatory view of a main part of the medium discharging apparatus according to the first embodiment of the present invention. 3 is an enlarged explanatory view of a main part of the guide member and the first gate according to the first embodiment of the present invention, FIG. 3A is a perspective explanatory view of the first gate, and FIG. 3B is the first gate at the first guide position. FIG. 3C is an explanatory diagram of a state in which the first gate has moved from the state of FIG. 3A to the second guide position. FIG. 4 is a diagram for explaining the operation of the first embodiment, and is a diagram for explaining a conventionally known guide member and a recording sheet in contact with the first gate. FIG. 4A shows the first gate corresponding to FIG. 4B is an explanatory view of the guide member and the first gate as viewed from the line IVB of FIG. 4A, and FIG. 4C is a sectional view taken along the line IVC-IVC of FIG. 4A. FIG. 5 is an enlarged explanatory view of the main part of the guide member and the first gate of the second embodiment of the present invention corresponding to FIG. 3 of the first embodiment, and FIG. 5A is a state in which the first gate is moved to the first guide position. FIG. 5B is an explanatory diagram of a state in which the first gate has moved from the state of FIG. 5A to the second guide position. 6 is an enlarged explanatory view of a main part of the electromagnetic solenoid according to the second embodiment of the present invention, and is a cross-sectional view taken along line VI-VI in FIG. FIG. 7 is an enlarged explanatory view of the main part of the guide member and the first gate of the third embodiment of the present invention corresponding to FIG. 3 of the first embodiment, and FIG. 7A is a state in which the first gate is moved to the first guide position. FIG. 7B is an explanatory diagram of a state in which the first gate has moved to the second guide position from the state of FIG. 7A, and FIG. 7C is an explanatory diagram of a state in which the second guide member is disposed at the neutral position. is there.

Explanation of symbols

1, 1 '... guide member, 1a ... contact surface of guide member, 1b, 1b ... guide side shaft portion, 1c, 1c ... guide side gear, 2, 3, 26, 27 ... contact surface of switching guide member, 2, 26 ... 1st contact surface, 3, 27 ... 2nd contact surface, 4, 4 ... Switching side shaft part, 6, 6 ... Guided part for switching, 7, 7 ... Switching side gear, 14, 14, 14 ', 14 '... switching guide part, 16, 16 ... connecting member, 16a, 16a ... guide side connecting part, 16b, 16b ... switching side connecting part, 21 ... first guide member, 21a ... contact surface of the first guide member, 22 ... second guide member, 22b ... contact surface of second guide member, 23 ... neutral position holder, BHS, BHS '... medium discharge device, F ... fixing device, GT1, GT1' ... switching guide member, Rb ... first Two-medium conveying member, Rh ... first medium conveying member, Rh + Rb ... medium conveying member, Rh + Rb + SH3 + SH4 1 + GT1, Rh + Rb + SH3 + SH4 + 1 ′ + GT1 ′: medium transport device, S: medium, SH3 + SH4: medium transport path, SH3: post-fixing transport path, SH4a: first medium transport path, SH4b: second medium transport path, TRh: medium discharge section, U: Image forming apparatus, Uy to Uk + BM + T2: Image recording apparatus.

Claims (9)

A post-fixing conveyance path disposed on the downstream side in the medium conveyance direction of a fixing device that heat-fixes an image on a medium, and a first medium conveyance path and a second medium conveyance path that branch from the downstream end of the conveyance path in the medium conveyance direction. And a medium conveyance path having
A guide member that guides the medium to the downstream side in the medium transport direction along the post-fixing transport path, the guide member having a flat contact surface that contacts the medium;
A switching guide member that is arranged downstream of the guide member in the medium conveyance direction and switches the medium conveyance direction to the first medium conveyance path or the second medium conveyance path and guides the medium, and contacts the medium The switching guide member having a contact surface formed in a planar shape;
A medium having a first medium conveying member arranged in the first medium conveying path and a second medium conveying member arranged in the second medium conveying path, and conveying the medium downstream in the medium conveying direction A conveying member;
A medium conveying apparatus comprising: The upstream side in the medium conveyance direction is the switching guide member configured to be rotatable along the medium thickness direction with respect to the downstream end in the medium conveyance direction of the guide member, and the upstream end in the medium conveyance direction of the switching guide member Moves to a position on the upstream side in the medium conveyance direction with respect to the downstream end in the medium conveyance direction of the guide member and on the opposite side of the conveyance path after fixing with the guide member interposed therebetween, thereby guiding the medium to the first conveyance path. The first guide position and the upstream end of the switching guide member in the medium transport direction move to a position opposite to the downstream end of the guide member in the medium transport direction across the post-fixing transport path. The switching guide member that moves between a second guide position that guides two transport paths;
A planar first contact surface that is exposed to the post-fixing conveyance path and guides the medium to the first medium conveyance path when the switching guide member moves to the first guidance position; and the switching guidance member A planar second contact surface that is exposed to the post-fixing conveyance path and guides the medium to the second medium conveyance path when moving to the second guide position;
The medium conveying apparatus according to claim 1, further comprising: The post-fixing conveyance path in which the upstream side in the medium conveyance direction extends upward from the fixing device and the downstream side in the medium conveyance direction is inclined with respect to the direction of gravity;
The guide member formed along the post-fixing conveyance path;
A medium discharge unit disposed on the downstream side in the medium transfer direction of the first medium transfer path and from which the medium is discharged;
When the medium transport direction is switched to the first medium transport path, the upstream end of the switching guide member in the medium transport direction is upstream of the guide member in the medium transport direction and the guide member The switching guide member that is disposed at a position opposite to the post-fixing conveyance path and that guides the medium to the medium discharge section along the first medium conveyance path;
The medium carrying device according to claim 1, wherein the medium carrying device is provided. A guide-side gear disposed outside the medium in the medium width direction and supported rotatably around a guide-side shaft portion extending in the medium width direction;
A switching side gear supported by the switching guide member and supported by a switching side shaft portion extending from the switching guide member toward the outside in the medium width direction, and meshing with the guide side gear;
A guided portion for switching supported by the switching guide member;
Engage with the switching guided portion and follow the trajectory of the switching guided portion when the switching side gear rotates and moves along the outer periphery of the guide side gear by forward and reverse rotation of the guide side gear. A switching guide unit that guides movement of the switching guide member between the first guide position and the second guide position,
The medium conveying apparatus according to claim 2, wherein the medium conveying apparatus is provided. A guide-side connecting portion as a rotation center that is disposed outside the medium width direction of the medium and supported by a downstream end portion of the guide member in the medium conveyance direction, and supported by an upstream end portion of the switching guide member in the medium conveyance direction. A switching member, and a connecting member that connects the guide member and the switching guide member;
A guided portion for switching supported by a downstream end portion of the switching guide member in a medium conveying direction;
By engaging with the guided part for switching and guiding along the locus of the switching side connecting part when the connecting member rotates by forward and reverse rotation with the guiding side connecting part as a rotation center, A switching guide for guiding the movement of the switching guide member between the first guide position and the second guide position;
The medium conveying apparatus according to claim 2, wherein the medium conveying apparatus is provided. A first guide member that guides the medium along the transport path after fixing to the downstream side in the medium transport direction, the first guide member having a flat contact surface in contact with the medium; and the medium And a contact surface that contacts the medium is formed in a planar shape, and is downstream of the first guide member in the medium conveyance direction, with the upstream end in the medium conveyance direction as the center of rotation. The second guide member, the side of which is rotatably supported, and the guide member,
When the medium is not in contact with the contact surface of the second guide member, the second guide member is held at a neutral position extending along an extension line of the post-fixing conveyance path, and the medium is in contact with the contact surface. A neutral position holding body that permits rotational movement of the second guide member,
The medium conveying apparatus according to claim 2, wherein the medium conveying apparatus is provided. The switching guide member configured such that the upstream side in the medium conveyance direction is rotatable about the downstream end in the medium conveyance direction, and
When the switching guide member moves from the second guiding position to the first guiding position and the second guiding member is pressed in contact with the switching guiding member, the fixing of the second guiding member is performed. When rotational movement to the opposite side of the rear conveyance path is permitted, and contact between the second guide member and the switching guide member is released before the switching guide member reaches the first guide position. The second guide member is returned to the neutral position, and the second guide member contacts the switch guide member when the switch guide member moves from the first guide position to the second guide position. The second guide member is allowed to rotate to the post-fixing conveyance path side, and before the switching guide member reaches the second guide position, When contact with the switching guide member is released Includes the intermediate position holding member for returning the second guide member to the neutral position,
The medium conveying apparatus according to claim 6, further comprising: A medium discharge unit for discharging the medium;
The medium conveying device according to any one of claims 1 to 7, wherein the medium is discharged to the medium discharging unit;
A medium discharge device comprising: An image recording apparatus for recording an image on a medium;
A fixing device for fixing an image on the surface of the medium;
The medium discharging apparatus according to claim 8, wherein the medium is discharged.
An image forming apparatus comprising:

Images