JP6015199B2 - Image forming apparatus - Google Patents

Description

  The present invention relates to an image forming apparatus, and more specifically, a user can easily remove jammed paper even if the trailing edge of a sheet nipped by a fixing device by a jam or the like is nipped by a standby roller pair or a secondary transfer unit. The present invention relates to an image forming apparatus capable of performing the above.

  Conventionally, an electrophotographic image forming apparatus is known. In this image forming apparatus, generally, a photosensitive drum is uniformly charged and initialized, an electrostatic latent image is formed on the photosensitive drum by optical writing, and the electrostatic latent image is converted into a toner image. Is directly or indirectly transferred onto a transfer material such as paper and fixed by a fixing unit.

  There are two types of toner image transfer: a method in which a toner image is directly transferred from an image forming unit to a sheet, and a method in which a toner image is primarily transferred from an image forming unit to an intermediate transfer member and then transferred from the intermediate transfer member to a sheet.

  In any case, in such an image forming apparatus, for example, when a paper jam occurs in the fixing unit, the user must put a hand into the apparatus and take out the jammed paper. However, in the fixing unit, the fixing temperature during printing is increased or decreased between 110 ° C. and 180 ° C.

  Therefore, if the user carelessly puts the hand into the apparatus in order to remove the jammed paper, there is a risk that a serious problem such as a burn will occur. However, especially when jammed paper is pinched by the rollers of the fixing unit and the trailing edge of the paper is pinched by the transfer unit or the standby roller pair, the user needs to put his hand deep inside the apparatus. The danger is stronger.

  In order to solve such a problem, for example, if a stick-shaped drawer member is arranged in advance on the side opposite to the paper take-out direction and the upper lid is opened when a jam occurs, the drawer member is interlocked with the opening of the upper lid. A mechanism has been proposed that lifts and pushes jammed paper out of the conveyance path. (For example, refer to Patent Document 1.)

No. 06-11991

  However, the technique of Patent Document 1 has been proposed for a monochrome image forming apparatus that directly transfers images from an image forming unit to paper, and is equipped with a multi-stage image forming unit that has been widely used in recent years. There is no suggestion or suggestion about the image transfer and secondary transfer system.

  The present invention solves the above-described conventional problems, and allows the user to easily remove jammed paper even if the trailing edge of the paper sandwiched between the fixing devices by jam or the like is sandwiched between the standby roller pair or the secondary transfer unit. An object of the present invention is to provide an image forming apparatus that can be removed.

In order to solve the above-described problems, an image forming apparatus according to the present invention includes a freely openable opening / closing cover provided so as to cover an opening of the apparatus, and a heat roller at least one of which is controlled by heating, and holds a sheet. A pair of transportable fixing rollers and a second position on the installation side of the opening / closing cover with respect to the paper transport path and a first position on the side beyond the paper transport path from the second position are movable. And an extrusion member disposed at a position along the fixing roller pair, and the extrusion member moves from the first position to the second position in accordance with the opening operation of the opening / closing cover. It is configured.

  The present invention provides an image forming apparatus that allows a user to easily remove jammed paper even if the trailing edge of the paper nipped by a fixing device due to jam or the like is nipped by a standby roller pair or a secondary transfer unit. be able to.

1 is a cross-sectional view illustrating an internal configuration of a full-color image forming apparatus (printer, apparatus main body) according to Embodiments 1 and 2 of the present invention. (a) is an external perspective view of the printer, and (b) is a view in which an opening / closing member integrated with a duplex printing conveyance unit is opened. (a) is a schematic diagram showing the relationship between the fixing unit and the engaging portion of the opening / closing member, (b) is a cross-sectional view more simply showing the inside of the apparatus body when the opening / closing member is not opened, (c) FIG. 4 is a diagram showing the state of the fixing unit at that time, (d) is a cross-sectional view showing the interior of the apparatus main body more simply when the opening / closing member is opened, and (e) is a diagram showing the state of the fixing unit at that time. is there. (a) is schematic which shows the relationship between the fixing unit based on Example 2, and the engaging part of an opening / closing member, (b) is sectional drawing which shows the inside when the opening / closing member of an apparatus main body is not open | released more simply (C) is a diagram showing the state of the fixing unit at that time, (d) is a cross-sectional view more simply showing the inside of the apparatus main body when the opening / closing member is opened, and (e) is a diagram of the fixing unit at that time. It is a figure which shows a state.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the description of the present invention, printing and printing are used synonymously.

  FIG. 1 is a cross-sectional view illustrating an internal configuration of a full-color image forming apparatus (hereinafter simply referred to as a printer or an apparatus main body) according to first and second embodiments.

  A printer 1 shown in FIG. 1 is an electrophotographic and secondary transfer tandem type color image forming apparatus, which is roughly divided into an image forming unit 2, an intermediate transfer belt unit 3, a paper feeding unit 4, and a duplex printing conveyance. The unit 5 is configured.

  The image forming unit 2 has a configuration in which four image forming units 6 (6M, 6Y, 6C, 6K) are arranged in a multistage manner from right to left in FIG.

  Of the four image forming units 6, three image forming units 6M, 6C and 6Y on the upstream side (the right side in the figure) are magenta (M), cyan (C) and yellow (subtractive three primary colors, respectively). A mono-color image is formed with the color toner of Y), and the image forming unit 6K forms a monochrome image with black (K) toner mainly used for dark portions of characters and images.

  Each of the image forming units 6 has the same configuration except for the color of the toner stored in the toner container (toner cartridge). Accordingly, the configuration of the black (K) image forming unit 6K will be described below as an example.

  The image forming unit 6 includes a photosensitive drum 7 at the bottom. The peripheral surface of the photosensitive drum 7 is made of, for example, an organic photoconductive material. A cleaner 8, a charging roller 9, an optical writing head 11, and a developing roller 13 of the developing device 12 are arranged around the periphery of the photosensitive drum 7.

  The developing device 12 puts one of magenta (M), cyan (C), yellow (Y), and black (K) toners in the upper toner container as indicated by M, C, Y, and K in the drawing. An intermediate portion is provided with a toner replenishing mechanism for the lower portion.

  In addition, the developing roller 13 is provided at the lower side of the developing device 12 at the side opening, and inside the toner supply roller 14 for supplying the toner to the developing roller 13, although not specifically shown, the toner agitation is not shown. A member, a doctor blade for regulating the toner layer on the developing roller 13 to a constant layer thickness, and the like are provided.

  The intermediate transfer belt unit 3 has an endless transfer belt 15 extending in a flat loop shape from substantially the left and right sides of the drawing at the substantially center of the apparatus body, and the transfer belt 15 is stretched over the transfer belt 15. A driving roller 16 and a driven roller 17 are provided to circulate and move the belt 15 counterclockwise in the figure.

  The transfer belt 15 transfers the toner image directly onto the belt surface (primary transfer) and conveys the toner image to the transfer position to the paper for further transfer (secondary transfer). The whole is called an intermediate transfer belt unit.

  The intermediate transfer belt unit 3 includes a belt position control mechanism 18 in the loop of the flat loop-shaped transfer belt 15. The belt position control mechanism 18 includes a primary transfer roller 19 made of a conductive foam sponge that presses against the lower peripheral surface of the photosensitive drum 7 via the transfer belt 15.

  The belt position control mechanism 18 uses the three primary transfer rollers 19 corresponding to the three image forming units 6M, 6C, and 6Y of magenta (M), cyan (C), and yellow (Y) as the same centering on the support shaft. Rotate with a period.

  Then, the belt position control mechanism 18 rotates and moves one primary transfer roller 19 corresponding to the black (K) image forming unit 6K separately from the three primary transfer rollers 19 so that the transfer belt 15 is photosensitive. Separated from the body drum 7.

  That is, the belt position control mechanism 18 determines the position of the transfer belt 15 of the intermediate transfer belt unit 3 in the full color mode (all four primary transfer rollers 19 are in contact with the transfer belt 15), monochrome mode (in the image forming unit 6K). Only the corresponding primary transfer roller 19 is in contact with the transfer belt 15) and all non-transfer modes (all four primary transfer rollers 19 are separated from the transfer belt 15).

  In the intermediate transfer belt unit 3, a belt cleaning unit 20 is disposed further upstream of the uppermost image forming unit 6 </ b> M in the belt moving direction. In addition, a flat and thin waste toner collecting container 21 is detachably disposed so as to extend along almost the entire central portion of the lower surface of the transfer belt 15.

  The cleaning unit 20 abuts on the upper surface of the transfer belt 15 to scrape and remove the waste toner, and collects the waste toner in a temporary storage unit of a belt cleaner unit (not shown). And is sent to the waste toner collecting container 21 via a dropping cylinder.

  The paper feed unit 4 includes two paper feed cassettes 22 (22a and 22b) arranged in two upper and lower stages, and near the paper feed port (right side in the drawing) of the two paper feed cassettes 22, respectively. A sheet take-out roller 23, a feeding roller 24, a separating roller 25, and a standby conveyance roller pair 26 are disposed.

  In the paper conveyance direction (vertical upward direction in the figure) of the standby conveyance roller pair 26, a secondary transfer roller 27 that is pressed against the driven roller 17 via the transfer belt 15 is disposed, and a secondary transfer portion to the paper is arranged. Forming.

  A belt-type heat fixing unit (hereinafter simply referred to as a fixing unit) 28 is disposed downstream (upward in the drawing) of the secondary transfer portion. The fixing unit 28 includes a fixing roller pair 31 composed of a heat roller 29 at least one of which is heated and controlled. The heat roller 29 spans a heat conducting belt 34 between a heat roller 33 having a heat source 32 therein.

  In addition, the fixing unit 28 is arranged at the outer end with respect to the rotation shaft 35 disposed at the inner end with respect to the apparatus main body 1 along the longitudinal direction of the fixing roller pair 31 (the depth direction in the drawing). Although the arrangement | positioning details are mentioned later, the engagement guide part which abbreviate | omits illustration in FIG. 1 is provided.

  In addition, the lower end portion of the fixing unit 28 outside the apparatus main body 1 is always urged upward at the outer end portion of the fixing unit 28 at a position not hindering the function of the engagement guide portion. A biasing member 36 is disposed.

  On the further downstream side (upward in the drawing) of the fixing unit 28, there is a pair of discharge rollers 38 for carrying out the fixed sheet from the fixing unit 28 and discharging it to a discharge tray 37 formed on the upper surface of the apparatus. It is arranged.

  The duplex printing conveyance unit 5 also serves as an opening / closing member whose right side cover opens or shields the inside of the printer 1 from the side to the outside. The duplex printing conveyance unit 5 includes a return path that branches from a conveyance path at an intermediate portion between the fixing unit 28 and the paper discharge roller pair 38 in the right lateral direction in the drawing.

  The return path includes a return start path 39a, a return intermediate path 39b that bends downward from the return path, a return end path 39c that bends in the left lateral direction opposite to the above and finally reverses the return sheet, and a middle of these return paths. Are provided with four pairs of return rollers 41a, 41b, 41c and 41d.

  The exit of the return termination path 41 c communicates with a conveyance path to the standby conveyance roller pair 26 corresponding to the sheet feeding cassette 22 b below the sheet feeding unit 4.

  FIG. 2A is an external perspective view of the printer 1, and FIG. 2B is a view in which an opening / closing member integrated with the duplex printing transport unit 5 is opened. 2A and 2B, the same components as those in FIG. 1 are given the same reference numerals as those in FIG.

  As shown in FIG. 2A, the printer 1 is provided with a front door 42 in the front, and an opening / closing member 43 as an opening / closing cover on the right side. The opening / closing member 43 has a handle 44 at the top. As shown in FIG. 2B, a person's hand 45 is put on the handle 44 of the opening / closing member 43, and the opening / closing member 43 is opened downwardly as indicated by an arrow a to open the fixing unit 28 from the side opening 46 of the apparatus main body 1. Can be exposed.

  As shown in FIG. 1, the printer 1 does not directly transfer the toner image from the image forming unit 6 to the sheet, but is intermediate between the sheet conveyed vertically to the secondary transfer unit by the standby conveyance roller pair 26. The toner image is secondarily transferred via the transfer belt 15.

  Therefore, since troubles such as paper jam do not occur in the arrangement portion of the kits concentrated on the left side of FIG. 1, the operation of attaching / detaching consumables such as kits is performed by opening the front door 40a shown in FIG. The kits are configured to be exchanged in the longitudinal direction (front door direction).

  That is, since a problem such as a paper jam occurring in the paper conveyance path occurs only on the right side of the apparatus main body, the maintenance process for recovering the paper jam etc. opens the right opening / closing member 43 shown in FIG. You can deal with it just by doing.

  However, although it can be dealt with by simply opening the opening / closing member 43, the jammed paper is sandwiched between the fixing roller pair 31 of the fixing unit 28, and the rear end of the paper is sandwiched between the secondary transfer unit and the standby roller pair 26. If this is the case, the user will need to reach deep into the device.

  As described above, the fixing unit 28 has a fixing temperature between 110 ° C. and 180 ° C. during execution of printing until immediately before the occurrence of paper jam. Therefore, if the user carelessly puts his / her hand into the apparatus to remove the jammed paper, there is a possibility that a malfunction such as a burn may occur.

  Accordingly, when the opening / closing member 43 is opened to remove jammed paper generated in the fixing unit 28, the inventor operates so that the jammed paper is ejected to a position where it can be easily taken out in conjunction with the opening of the opening / closing member 43. Invented the engaging part. This will be described below.

  FIG. 3A is a schematic diagram showing the relationship between the fixing unit 28 and an engaging portion 47 described later of the opening / closing member 43, and FIG. 3B is a view in which the opening / closing member 43 is not opened as in FIG. 2A. FIG. 3C is a sectional view showing the interior of the apparatus main body 1 more simply, FIG. 3C is a diagram showing the state of the fixing unit 28 at that time, and FIG. 3D is opened and closed as shown in FIG. FIG. 3E is a sectional view showing the interior of the apparatus main body 1 more simply when the member 43 is opened, and FIG. 3E is a view showing the state of the fixing unit 28 at that time.

  3 (a) to 3 (e), the same components as those in FIGS. 1 and 2 (a) and 2 (b) are denoted by the same reference numerals as those in FIGS. 1 and 2 (a) and 2 (b). , Only the parts that are considered necessary for explanation are given. 3 (b) and 3 (d), illustration of the accessory members around the fixing unit 28 is omitted for the sake of brevity. However, FIG. 1 shows the engaging portion 47 and the jammed paper 48 which are not shown.

  As shown in FIGS. 3A to 3C, the fixing unit 28 includes an engagement guide portion 49 disposed at the outer end with respect to the apparatus main body 1 in addition to the rotation shaft 35 shown in FIG. I have. The engagement guide portion 49 has a circular arc shape spreading outward. Thereby, when the opening / closing member 43 is closed, the engaging portion 47 integral with the opening / closing member 43 easily enters the engaging guide portion 49 and engages with the engaging guide portion 49.

  By this engagement, the engaging portion 47 resists the urging force of the upper urging member 36 shown in FIG. 1 and cooperates with the rotating shaft 35 to fix the fixing unit 28 in FIGS. 3 (a) and 3 (c). The fixing execution posture shown in FIG.

  Then, when the paper is not passed through the fixing unit 28 and the rear end portion of the sheet is jammed with the secondary fixing portion, the opening / closing member 43 is opened as shown in FIG. Then, the engagement between the engagement guide portion 49 and the engagement portion 47 is released.

  When the engagement between the engagement guide portion 49 and the engagement portion 47 is released in this way, as shown in FIGS. 3 (d) and 3 (e), the fixing unit 28 has the upper biasing member shown in FIG. 3, the rotating shaft 35 is pivoted upward from the fixing execution posture shown in FIG. 3 (c) by the urging force 36, and the fixing roller pair 31 is rotated as shown in FIGS. 3 (d) and 3 (e). The rear portion 48a of the nipped paper 48 is bent in a convex shape toward the outside of the apparatus main body 1.

  As described above, when the opening / closing member 43 is opened, the outer end portion of the fixing unit 28 is rotated upward to increase the distance from the secondary transfer portion, and the rear end 48a of the jammed paper 48 is directed outward. By being bent in a convex shape, the user can easily take out the jammed paper without touching the hot fixing unit 28 by mistake.

  FIG. 4A is a schematic diagram illustrating the relationship between the fixing unit according to the second embodiment and the engaging portion of the opening / closing member, and FIG. 4B is the apparatus body 1 in which the opening / closing member 43 is opened as shown in FIG. FIG. 4C is a cross-sectional view showing the inside of the apparatus main body 1 in a simplified manner when not done, and FIG. 4C is a view showing the state of the fixing unit 28 at that time.

  FIG. 4D is a cross-sectional view showing, in a simplified manner, the inside of the apparatus main body 1 when the opening / closing member 43 is opened as shown in FIG. 2B in the apparatus main body 1 according to the second embodiment. FIG. 4E shows the state of the fixing unit 28 at that time.

  4A to 4E are the same as those shown in FIGS. 3A to 3E except for the configuration around the fixing unit 28. Therefore, FIGS. The same numbers as in e) are given only to the parts that are considered necessary for the explanation.

  Also in this example, for the sake of brevity, FIGS. 4B and 4D partially omit the illustration of the accessory members around the fixing unit 28. However, the longer engaging portion 51, the jammed paper 48, and the rod-shaped body 52 newly added in this example are illustrated.

  As shown in FIG. 4 (c), in this example as well, the fixing unit 28 has an arc shape that spreads outwardly from the rotation axis 35 and is arranged at the outer end with respect to the apparatus body 1. A joint guide 49 is provided.

  In this example, the engagement guide portion 49 further includes a long hole portion 53 that extends from the lower outer end side of the fixing unit 28 to the inner side of the center portion. The long hole portion 53 supports the rod-like body 52 that is arranged along the longitudinal direction of the fixing roller pair 31 and is fitted at both ends.

  Although not shown in the drawing, the bar-like body 52 is provided with a lateral biasing member that constantly biases the bar-like body 52 toward the outside of the apparatus main body 1. When the opening / closing member 43 is closed, the longer engaging portion 51 integrated with the opening / closing member 43 has its tip engaged with the engagement guide portion 49 and further toward the inside of the apparatus main body than the center portion of the fixing unit 28. invade.

  Both ends of the rod-like body 52 arranged in the intrusion path at the tip of the longer engaging portion 51 are pushed by the tip of the longer engaging portion 51 to resist the biasing force of the lateral biasing member. Then, it moves to the left end side of the long hole portion 53 (inward direction of the apparatus body 1).

  As shown in FIGS. 4B and 4C, the moved position is a position located in the inner direction of the apparatus main body 1 with respect to the conveyance path of the paper 48. This is the first position in this example.

  In this state, the longer engaging portion 51 opposes the urging force of the upper urging member 36 and pushes the rod-like body 52 into the first position against the urging force of the lateral urging member. The fixing unit 28 is held in the fixing execution posture shown in FIGS.

  Then, when the paper is not passed through the fixing unit 28 and the rear end portion is sandwiched between the secondary fixing portions and is jammed, the opening / closing member 43 is opened as shown in FIG. Then, the engagement between the engagement guide portion 49 and the longer engagement portion 51 is released.

  When the engagement between the engagement guide portion 49 and the longer engagement portion 51 is released in this way, as shown in FIGS. 4D and 4E, the fixing unit 28 has the superscript shown in FIG. With the urging force of the urging member 36, the rotating shaft 35 is pivoted about the fulcrum and is rotated upward from the fixing execution posture of FIG.

  Simultaneously with this upward rotation, the rod-like body 52 released from the longer engagement portion 51 is released by the biasing force of the lateral biasing member as shown in FIG. Move to the right end side (outside direction of the apparatus main body 1).

  As shown in FIGS. 4D and 4E, the moved position is a position located in the outer direction of the apparatus main body 1 with respect to the conveyance path of the paper 48. This is the second position in this example. As shown in FIGS. 4D and 4E, the rod-like body 52 moved from the first position to the second position moves the rear portion 48a of the paper 48 sandwiched between the fixing roller pair 31 to the outside of the apparatus main body 1. Bend in a convex shape in the direction.

  As described above, also in this example, when the opening / closing member 43 is opened, the outer end portion of the fixing unit 28 rotates upward to increase the distance from the secondary transfer portion, and the rear end of the jammed paper 48. 48a is forcibly pushed outward by the rod-like body 52, so that the user can easily take out the jammed paper without touching the hot fixing unit 28 by mistake.

  In the above embodiment, the hinge of the fixing unit is provided at the lower end of the fixing unit facing the inside of the apparatus main body. However, the present invention is not limited to this, and the hinge is provided at any position up to the upper end. May be.

  In addition, the upper urging member that urges the fixing unit upward is provided at the lower end portion of the fixing unit facing the outer side with respect to the main body of the fixing unit. You may make it provide.

Although several embodiments of the present invention have been described, the present invention is included in the invention described in the claims and the equivalents thereof. Hereinafter, the invention described in the scope of claims of the present application will be appended.
[Appendix 1]

The device body;
A fixing roller pair having at least one heat roller that is heated and controlled and capable of holding and conveying a sheet is provided, and a fixing execution posture with respect to the apparatus main body with a rotation shaft along the longitudinal direction of the fixing roller pair as a fulcrum And a fixing unit that is rotatably supported in a retracted position,
A biasing member that biases the fixing unit in the retracted posture direction;
An openable openable cover that forms the outer surface of the apparatus body;
The opening / closing cover is engaged with the fixing unit when the opening / closing cover is closed, resists the urging force of the urging member, holds the fixing unit in the fixing execution posture, and opens the opening / closing cover. An engagement portion for releasing the engagement;
An image forming apparatus comprising:
[Appendix 2]

When the engaging portion releases the engagement with the fixing unit, the fixing unit rotates upward from the fixing execution posture by the urging force of the urging member and is sandwiched between the fixing roller pair. Bend in a convex shape outwardly of the apparatus body so that the rear part can be easily gripped,
The image forming apparatus as set forth in appendix 1, wherein:
[Appendix 3]

3. The image forming apparatus according to claim 1, wherein the fixing unit includes an engagement guide portion that guides the engagement with the engagement portion.
[Appendix 4]

A first position located along the longitudinal direction of the fixing roller pair and inward of the apparatus main body with respect to the paper conveyance path, and a second position located in the outer direction of the apparatus main body with respect to the paper conveyance path. A movable rod,
A lateral urging member that urges the rod-shaped body in an outer direction of the apparatus main body;
Further comprising
The engaging portion engages with the lateral urging member when the opening / closing cover is closed, pushes the rod-shaped body into the first position against the urging force of the lateral urging member, and Release the engagement with the lateral biasing member at the time of opening,
The bar-like body moves from the first position to the second position by the urging force of the lateral urging member when the engagement is released, and the rear portion of the sheet sandwiched between the fixing roller pair is moved to the apparatus. Configured to push outward in the body,
The image forming apparatus according to Supplementary Note 3, wherein

  The present invention is used in an image forming apparatus that allows a user to easily remove jammed paper even if the trailing edge of the paper nipped by a fixing device due to jam or the like is nipped by a standby roller pair or a secondary transfer unit. be able to.

1. Image forming device (printer, device body)
2 Image forming unit 3 Intermediate transfer belt unit 4 Paper feed unit 5 Double-sided printing transport unit 6 (6M, 6Y, 6C, 6K) Image forming unit 7 Photosensitive drum 8 Cleaner 9 Charging roller 11 Optical writing head 12 Developer 13 Developing roller 14 Toner supply roller 16 Drive roller 17 Driven roller 18 Belt position control mechanism 19 Primary transfer roller 20 Belt cleaner unit 21 Waste toner collection container 22 (22a, 22b) Paper feed cassette 23 Paper take-out roller 24 Feed roller 25 Rolling roller 26 Standby conveying roller pair 27 Secondary transfer roller 28 Belt-type thermal fixing unit (fixing unit)
29 Heat roller 31 Fixing roller pair 32 Heat source 33 Heat generating roller 34 Heat conduction belt 35 Rotating shaft 36 Upper biasing member 37 Paper discharge tray 38 Paper discharge roller pair 39a Return start path 39b Return intermediate path 39c Return end path 41a, 41b, 41c, 41d Return roller pair 42 Front door 43 Opening / closing member 44 Handle 45 Human hand 46 Side opening 47 Engagement part 48 Jam paper 49 Engagement part 51 Longer engagement part 52 Rod-like body 53 Long hole part

Claims (4)

An openable and closable opening / closing cover provided to cover the opening of the device;
A pair of fixing rollers , at least one of which is a heat roller, capable of nipping and conveying paper;
The fixing roller pair is configured to be movable between a second position on the installation side of the opening / closing cover and a first position on the side beyond the paper conveyance path with respect to the paper conveyance path. An extrusion member arranged at a position along,
A first urging member that urges the pushing member from the first position toward the second position;
The opening / closing cover is engaged with the pushing member when the opening / closing cover is closed, and pushes the pushing member against the urging force of the first urging member to the first position. An engaging portion for releasing the engagement at the time of opening;
With
The pushing member moves from the first position to the second position by the urging force of the first urging member by releasing the engagement, and moves the rear part of the sheet sandwiched by the fixing roller pair. It is configured to push out to the installation side of the opening and closing cover,
An image forming apparatus. The extrusion member is rod-shaped,
The image forming apparatus according to claim 1. A fixing frame that rotatably supports the fixing roller pair in a fixing execution posture and a retracted posture with respect to the apparatus with a rotation axis along the fixing roller pair as a fulcrum;
A second urging member that urges the fixing roller pair in the retracted posture direction;
With
The engaging portion engages with the fixing frame when the opening / closing cover is closed, holds the fixing roller pair in the fixing execution posture against the urging force of the second urging member, and the opening / closing cover. Disengaging the engagement when opening
The image forming apparatus according to claim 1, wherein the image forming apparatus is an image forming apparatus. The fixing roller pair is configured to easily grip the rear portion of the sheet nipped by the fixing roller pair by the urging force of the second urging member when the engaging portion is disengaged from the fixing frame. Rotating to bend in a convex shape in the direction of the opening / closing cover with respect to the paper transport path,
The image forming apparatus according to claim 3.