JP2012008452A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device allowing extraction of a fixing unit even when a conveyance unit is closed.SOLUTION: An image forming device comprises: a fixing unit (12)which has a roller pair (30 and 31) for fixing an image on a recording material in the nip formed between the rollers, of which one roller forming a nip is disposed between a conveyance path (60) for a single-sided printing sheet and a conveyance path (70) for a double-sides-d printing sheet, and which may be drawn in an image forming device body (2) and drawn out/detached therefrom; a conveyance unit (40) which has the conveyance path for single-sided printing and a conveyance path for double-sided printing, and moves on a rotating track crossing a track for withdrawing the fixing unit when the conveyance path for a single-sided printing is externally opened by rotating relatively the image forming device body; and a conveyance guide (45) which is disposed in the conveyance unit and fills a gap between the fixing unit and the conveyance unit in the conveyance path for double-sided printing. The conveyance guide retreats from the track of withdrawing the fixing unit when the fixing unit is withdrawn.

Description

  The present invention relates to an image forming apparatus having conveyance paths for single-sided printing and double-sided printing.

In this type of image forming apparatus, for example, an apparatus using an electrophotographic process, the photosensitive drum is charged in advance, and the surface of the photosensitive drum is irradiated with laser light to form an electrostatic latent image. Then, the developed toner image is transferred and fixed on a sheet.
Next, the recording material that has undergone this fixing step is sent to a paper discharge tray in the case of single-sided printing, and to the conveyance path for double-sided printing in the case of double-sided printing.

  As described above, the recording material is sent out in various directions via the branch position located on the downstream side of the fixing unit (see, for example, Patent Document 1). More specifically, in the fixing unit, the nip of the roller pair is positioned on the conveyance path for single-sided printing, and one roller forming this nip is connected between the conveyance path for single-sided printing and the conveyance path for double-sided printing. These conveyance paths for single-sided printing and double-sided printing are connected at a branch position on the downstream side of the fixing unit.

  On the other hand, the conveyance path for double-sided printing is connected to the conveyance path for single-sided printing at the merging position on the upstream side of the fixing unit. This merging position is provided in the conveying unit, and when the conveying unit is rotated with respect to the image forming apparatus main body, the one-side printing conveying path near the merging position is opened to the outside. As a result, the recording material remaining in the conveyance path for single-sided printing can be easily removed.

JP 2007-91359 A

By the way, the fixing unit adjacent to the above-mentioned transport unit has a structure that can be pulled out, for example, in the horizontal direction with respect to the image forming apparatus main body, and the rotation trajectory of the transport unit may intersect the trajectory of the fixing unit. .
More specifically, a conveyance guide is erected on the conveyance path for duplex printing in the conveyance unit, and the conveyance guide fills a gap between the fixing unit and the conveyance unit.

If the gap is not filled, the recording material in the conveyance path for single-sided printing enters the gap and goes to the conveyance path for double-sided printing without going through the fixing unit, or the recording material in the conveyance path for double-sided printing. This is because it goes to the conveyance path for single-sided printing via the gap.
However, in the structure in which the conveyance guide is provided on the locus where the fixing unit is drawn, when the fixing unit is replaced or maintenance is performed, the conveyance unit is first rotated and opened, and then the fixing unit is not pulled out. There is a problem that the unit collides with the conveyance guide and the conveyance unit is damaged.

In addition, if it is necessary to always rotate the transport unit, there is a problem that workability for the fixing unit is not good.
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an image forming apparatus that solves the above-described problems and that allows the fixing unit to be pulled out even when the transport unit is closed.

  A first invention for achieving the above object has a roller pair for fixing an image to a recording material at the nip, and one of the rollers forming the nip is a conveyance path for single-sided printing of the recording material and a double-sided printing. The image forming apparatus main body has a fixing unit which is arranged between the image forming apparatus main body and is detachable by being pulled out from the image forming apparatus main body, a single-sided printing conveying path and a double-sided printing conveying path. And a conveyance unit that moves on a rotation trajectory that intersects the trajectory drawn by the fixing unit when the conveyance path for single-sided printing is opened to the outside. A conveyance guide for filling a gap between the fixing unit and the conveyance unit in the conveyance path for printing is provided, and the conveyance guide is retracted from a locus of the fixing unit when the fixing unit is pulled out.

  According to the first invention, the main body of the image forming apparatus is provided with a conveyance path for single-sided printing and a conveyance path for double-sided printing, and the recording material on which the image is fixed by the fixing unit is for single-sided printing. It can be sent again from the conveyance path toward the conveyance path for double-sided printing toward the fixing unit. Further, when removing the recording material remaining in the conveyance path for single-sided printing, the user rotates the conveyance unit with respect to the main body of the image forming apparatus and opens the conveyance path for single-sided printing to the outside.

Further, a conveyance guide is provided in the conveyance path for double-sided printing in the conveyance unit. However, the conveyance guide of the present invention is retracted from the locus of pulling out the fixing unit when the fixing unit is pulled out.
Therefore, the fixing unit can be pulled out even in the closed state where the transport unit does not rotate. As a result, breakage of the transport unit can be prevented and workability improvement for the fixing unit can be achieved.

According to a second aspect of the invention, in the configuration of the first aspect of the invention, the conveyance unit is rotatably supported by the image forming apparatus main body at a position closer to the direction in which the conveyance unit is opened than the formation position of the conveyance path for single-sided printing. It is characterized by having a unit side shaft portion.
According to the second invention, in addition to the operation of the first invention, when the unit side shaft portion is located on the side of the direction of opening the transport unit with respect to the transport path for single-sided printing, the trajectory of the fixing unit and the transport unit Since the rotation trajectory intersects at a deeper position, the interference between the fixing unit and the transport unit becomes remarkable, and the transport unit is more easily damaged. Can be avoided.

According to a third invention, in the configuration of the first or second invention, a fixing unit is mounted and a rail member configured to be horizontally movable with respect to the image forming apparatus main body is provided.
According to the third invention, in addition to the effects of the first and second inventions, the rail member is configured so that the fixing unit can be pulled out in the horizontal direction, and the workability for the heavy fixing unit is further improved. improves.

According to a fourth aspect of the invention, in the configuration of the third aspect of the invention, the transport guide retracted as the fixing unit is pulled out contacts the rail member and maintains its retracted posture.
According to the fourth aspect of the invention, in addition to the action of the third aspect of the invention, when the heavy fixing unit is pulled out, the conveyance guide is restricted by the rail member and remains in its retracted posture. Therefore, the operation of pulling out the fixing unit in the horizontal direction can be quickly performed without being interrupted by the conveyance guide.

According to a fifth invention, in the configuration of the first to fourth inventions, the conveyance guide has a guide side shaft portion rotatably supported with respect to the conveyance unit.
According to the fifth invention, in addition to the effects of the first to fourth inventions, the transport guide is further divided from the transport unit and is rotated with respect to the transport unit about the guide side shaft portion. The fixing unit can be pulled out more reliably even in the closed state where the transport unit does not rotate.

  According to the present invention, there is provided an image forming apparatus in which the conveyance guide is retracted from the locus of pulling out the fixing unit when the fixing unit is pulled out, and the fixing unit can be pulled out even when the conveyance unit is closed. be able to.

1 is a perspective view of a multifunction machine according to an embodiment. FIG. 2 is a front view of a vertical section schematically showing the multifunction machine of FIG. 1. FIG. 3 is a cross-sectional view of the periphery of the fixing unit of FIG. 2 as viewed from the back of the multifunction peripheral. FIG. 4 is a perspective view of a state where an exterior cover and a transport unit of FIG. 3 are opened. FIG. 4 is a perspective view showing a state in which only the exterior cover is opened from FIG. 3. FIG. 6 is a perspective view illustrating a state in which the fixing unit is pulled out from FIG. 5. It is a fragmentary perspective view of the conveyance guide of FIG. It is a fragmentary perspective view of the conveyance guide of FIG. It is a fragmentary perspective view of the conveyance guide of FIG. It is a fragmentary perspective view of the conveyance guide of FIG. FIG. 4 is an explanatory diagram of the fixing unit rail of FIG. 3. It is operation | movement explanatory drawing of the conveyance guide of FIG. It is operation | movement explanatory drawing of the conveyance guide of FIG. It is operation | movement explanatory drawing of the conveyance guide of FIG. It is operation | movement explanatory drawing of the conveyance guide of FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a multifunction machine 1 as an example of an image forming apparatus from the upper right front, and the front surface of the multifunction machine 1 facing the user and the right side surface of the multifunction machine 1 can be seen. The multifunction machine 1 includes an in-body discharge type apparatus main body (image forming apparatus main body) 2, and a discharge tray 18 is formed at a central portion of the apparatus main body 2.

A document feeder 8 is mounted on the upper side of the apparatus main body 2. When the multifunction machine 1 is used as a copying machine, a facsimile, or a network scanner, a document is transported from the document feeder 8, and its image surface is an optical type. Optically read by the scanner unit 9.
An operation panel 25 is installed on the front side of the scanner unit 9. The operation panel 25 is provided with an operation screen 26 on which a plurality of operation keys and switches for various user operations are arranged and various information is displayed.

  On the other hand, a front loading type paper supply device 3 is disposed at the lower part of the apparatus main body 2. Specifically, two upper and lower sheet feed cassettes 4 are provided along the height direction of the apparatus body 2, and each sheet feed cassette 4 is configured to be detachable from the apparatus body 2. An openable manual feed tray 5 is also provided on the right side surface of the apparatus main body 2.

The inside of the multifunction machine 1 is shown in FIG. In addition, the arrow shown with the continuous line in the figure represents the conveyance direction of a paper (recording material).
As shown in FIG. 2, various types of paper P before image formation are stored in the paper feed cassette 4 in a stacked state, and the paper is separated one by one from the paper feed cassette 4 and sent leftward. The

As shown in FIG. 2, a paper transport unit 6 is disposed on the left side of the paper supply device 3, and the paper delivered from the paper feed cassette 4 is transported upward along the left side surface of the device body 2. Further, the sheet fed from the manual feed tray 5 is also transported from the right side of the apparatus main body 2 toward the left direction, and then transported upward.
Inside the apparatus main body 2, a registration roller 7, an image forming unit 10, and a transfer unit 11 are sequentially arranged on the downstream side in the sheet conveyance direction.

As shown in FIG. 2, an exposure unit 14 is provided on the right side of the image forming unit 10, and laser light is irradiated from the exposure unit 14 toward the photosensitive drum of the image forming unit 10.
In addition, a fixing unit 12 having a roller pair, which will be described later, and a discharge branching unit 13 are sequentially arranged on the downstream side of the transfer unit 11 when viewed in the paper conveyance direction. The discharged paper is discharged to the paper discharge tray 18 through the discharge branching section 13.

On the other hand, conveyance paths 70 u and 70 d for double-sided printing are formed along the left side surface of the apparatus body 2 between the discharge branching unit 13 and the sheet conveyance unit 6.
Specifically, the double-sided printing conveyance path 70u is positioned upstream of the double-sided printing conveyance path 70d in the paper conveyance direction, and the double-sided printing conveyance paths 70u and 70d are sent from the fixing unit 12. The sheet is returned to the supply junction 15 and sent again from the conveyance path 60u for single-sided printing toward the image forming unit 10.

That is, the conveyance paths 60u and 60d for single-sided printing are conveyance paths from the supply merging unit 15 to the discharge branching unit 13 via the image forming unit 10, the fixing unit 12, and the like, and the conveyance path 60u for single-sided printing is It is located upstream of the conveyance path 60d for single-sided printing when viewed in the sheet conveyance direction.
Here, an exterior cover 19 is installed on the left side surface of the apparatus main body 2. The exterior cover 19 is configured to be rotatable with the lower end as a fulcrum with respect to the apparatus main body 2 and covers the fixing unit 12 above.

  Specifically, as shown in FIG. 3 as viewed from the back side of the multifunction machine 1, the fixing unit 12 of the present embodiment includes a roller pair including a pressure roller (one roller) 30 and a fixing roller 31, and fixing. A heating unit 32 for induction heating the surface layer portion of the roller 31 is provided. When viewed from the left side of the apparatus main body 2 (the right side in FIG. 3), the heating unit 32 is disposed on the back side of the pressure roller 30 and the fixing roller 31.

  More specifically, the fixing roller 31 faces the heating unit 32, the nip between the fixing roller 31 and the pressure roller 30 is positioned on the conveyance path 60d for single-sided printing, and the pressure roller 30 is used for single-sided printing. It is arranged between the conveyance path 60d and the conveyance path 70u for double-sided printing. The toner image is heated and melted in the nip by induction heating of the surface layer portion of the fixing roller 31.

Further, the fixing unit 12 of this embodiment has a fixing unit frame 34 that covers the periphery thereof, and can be pulled out from the apparatus main body 2 together with the fixing unit frame 34 in the horizontal direction (rightward as viewed in FIG. 3). Has been. The point where the fixing unit 12 is attached to and detached from the apparatus main body 2 will be described later.
On the other hand, a transport unit 40 is installed below the fixing unit 12.

The transport unit 40 of this embodiment forms a transport path 60u for single-sided printing and a transport path 70d for double-sided printing, and can rotate with respect to the apparatus main body 2 with the unit side shaft portion 42 as a fulcrum (see FIG. 4, 14).
Specifically, the transport unit 40 includes the supply merging unit 15, the registration roller 7, and the transfer roller 17 of the transfer unit 11 on the transport path 60 u side for single-sided printing.

The unit-side shaft portion 42 is closer to the double-sided printing conveyance path 70d than the formation position of the single-sided printing conveyance path 60u, in other words, the direction side in which the conveyance unit 40 is rotated and opened (referred to in FIG. 14). For example, on the right).
When a paper jam or the like occurs in the conveyance path 60u for single-sided printing, the exterior cover 19 is rotated from the apparatus main body 2, and the conveyance unit 40 is further rotated from the apparatus main body 2 for single-sided printing. The conveyance path 60u is opened and jam processing is performed (FIG. 4).

  On the other hand, as shown in FIG. 5 in which only the transport unit 40 is returned from the state of FIG. 4, the transport unit 40 has the transport roller 43 on the upper side and the transport roller 44 on the lower side on the transport path 70d side for double-sided printing. Each has. That is, when a paper jam or the like occurs in the double-sided printing conveyance path 70d, only the exterior cover 19 is rotated from the apparatus main body 2 to open the double-sided printing conveyance path 70d, and jamming is performed.

As described above, the transport unit 40 of this embodiment is adjacent to the lower side of the fixing unit 12, but there is a gap that affects the transportability of the sheet at the boundary with the fixing unit 12.
Therefore, the transport unit 40 includes a transport guide 45, and the transport guide 45 eliminates a space generated between the front surface 35 of the fixing unit frame 34 and the transport roller 43. The front surface 35 corresponds to the above-described conveyance path 70u for double-sided printing.

By the way, the fixing unit 12 of the present embodiment is pulled out in the horizontal direction as described above, whereas the transport guide 45 of the transport unit 40 is arranged on the locus where the fixing unit 12 is pulled out.
That is, when the fixing unit 12 is pulled out from the apparatus main body 2 for unit replacement, maintenance, etc., the conveyance unit 40 is first rotated to avoid interference between the conveyance guide 45 and the fixing unit frame 34 in advance. It is necessary to keep it.

However, in this embodiment, since the conveyance guide 45 can be retracted from the locus of the fixing unit 12 being drawn, even if the fixing unit 12 is pulled out immediately without rotating the conveyance unit 40 as shown in FIG. Interference between the fixing unit frame 45 and the fixing unit frame 34 can be avoided.
Specifically, the conveyance guide 45 of the present embodiment includes a guide side shaft portion 46, a blindfold portion 47, and a torsion coil spring 52 (FIGS. 7 and 8).

The guide-side shaft portion 46 extends along the front-rear direction of the multifunction machine 1 and is supported so as to be rotatable with respect to the upper end of the transport unit 40.
7 corresponds to the left side (back side of the multifunction device 1) as viewed in FIG. 5, and FIG. 8 corresponds to the right side (front side of the multifunction device 1) as viewed in FIG. Further, in FIG. 7 and the like illustrating the conveyance guide 45, the fixing unit frame 34 is omitted in order to clearly show the shape of the conveyance guide 45.

The blindfold 47 extends along the front-rear direction of the multifunction machine 1, and its lower end is connected to the guide side shaft 46, and the upper end of the blindfold 47 is configured to be rotatable with respect to the upper end of the transport unit 40. Yes.
In addition, the blindfold 47 is formed in a U-shaped cross section (FIG. 3), the transport surface 48 forms a U-shaped lid portion, and as shown in FIGS. The end portions 50 and 50 are flush with the conveyance path 70d for double-sided printing, and the inner surface 49, which is a U-shaped opening, faces the inside of the apparatus main body 2.

The torsion coil spring 52 is disposed at the front end 50 of the multi-function device 1 in the blindfold 47 (FIG. 8), and the coil portion wound around the guide shaft 46, the blindfold 47, and double-sided printing. Arm portions respectively in contact with the conveyance path 70d for use, and urging the blindfolded portion 47 in a standing direction.
Thus, when the inner surface 49 of the blindfold 47 is pressed outwardly from the apparatus main body 2, the conveying guide 45 in the standing posture first falls so as to close the gap between the conveying paths 70 u and 70 d for double-sided printing. .

  More specifically, the conveyance guide 45 rotates the upper end of the blindfold 47 toward the outside of the apparatus main body 2 against the urging force of the torsion coil spring 52, and as shown in FIG. It begins to fall over so as to cover the conveyance path 70d for use. Next, when the upper side of the main body 2 of the inner surface 49 is pressed, the upper end of the blindfold portion 47 is tilted against the urging force of the torsion coil spring 52 until the upper end of the blindfold portion 47 rotates about 90 ° from the standing posture (FIG. 10).

The orientation of the conveyance guide 45 shown in FIG. 10, that is, the orientation in which the blindfolded portion 47 is completely tilted and the inner surface 49 on the opposite side faces upward is the fixing unit frame 34 and the fixing unit rail (rail member) shown in FIG. ) Maintained at 22.
The fixing unit frame 34 has a front surface 35 as viewed from the left side surface of the multifunction machine 1, a bottom surface 36 positioned below the front surface 35, and the like in the cross-sectional view of FIG.

The bottom surface 36 is formed in a stepped shape that gradually descends toward the back side of the apparatus main body 2 and covers the lower side of the pressure roller 30. Further, the bottom surface 36 extends toward the back side of the apparatus main body 2, covers the lower part of the fixing roller 31 and the heating unit 32, and is placed on the fixing unit rail 22.
Further, the bottom surface 36 forms an opening that connects the conveyance path 60u and the conveyance path 60d for single-sided printing shown in FIG. 3, and both ends of the opening of the bottom surface 36 are completely collapsed as shown in FIG. The upper side of the apparatus main body 2 at the end portions 50 and 50 of the inner surface 49 of the conveyance guide 45 can be pressed.

  As shown in FIG. 11, the fixing unit rail 22 includes a front surface 23 on which a bottom surface 36 positioned below the fixing roller 31 and the heating unit 32 is placed, and a rear surface 24 that faces the apparatus main body frame 20 that houses the fixing unit 12. And is supported so as to be swingable with respect to the apparatus main body frame 20 in the left-right direction as viewed in FIG. The back surface 24 of the fixing unit rail 22 can press the upper side of the main body 2 of the inner surface 49 of the conveyance guide 45 shown in FIG.

  When pulling out the fixing unit 12 from the apparatus main body 2, when the lever 21 is grasped in FIG. 12 in which only the exterior cover 19 is opened and the fixing unit 12 is pulled out in the horizontal direction, the fixing unit rail 22 becomes the apparatus main body frame. The fixing unit 12 is pulled out together with the fixing unit frame 34 in order to slide with respect to 20.

At this time, the conveyance guide 45 erected in FIG. 12 first has its inner surface 49 in contact with the upper part of the bottom surface 36 of the fixing unit frame 34, and pulls out the fixing unit 12 against the urging force of the torsion coil spring 52. It turns in the direction and begins to fall (FIG. 13).
Next, when the fixing unit 12 is pulled out slightly larger, the inner surface 49 comes into contact with the lower part of the bottom surface 36, rotates about 90 ° from the standing posture against the urging force of the torsion coil spring 52, and completely falls down.

Even if the fixing unit 12 is pulled out more greatly, the completely tilted conveyance guide 45 has its end portions 50 and 50 pressed from above the apparatus body 2 at both ends of the opening of the bottom surface 36, so that the torsion coil spring It is maintained in a completely collapsed posture against the urging force of 52 (FIG. 14).
Thereafter, when the fixing unit 12 is further drawn out, the conveyance guide 45 is handed over to the fixing unit rail 22 and its inner surface 49 comes into contact with the back surface 24 of the fixing unit rail 22 (FIG. 15). Thereby, the conveyance guide 45 is maintained in this completely tilted posture.

When the fixing unit 12 is pulled out to the largest extent and the handle 38 is grasped and the fixing unit 12 is pulled up, the fixing unit 12 is removed together with the fixing unit frame 34 to the outside of the apparatus main body 2.
Note that the fixing unit rail 22 remains in the apparatus main body 2 while being pulled out in the horizontal direction. When the fixing unit 12 that has undergone unit replacement is placed on the fixing unit rail 22 and pushed into the apparatus main body 2, the fixing unit rail 22 is completely removed. The conveyance guide 45 in the collapsed posture gradually rises due to the urging force of the torsion coil spring 52.

When the fixing unit 12 is completely pushed in, the conveyance guide 45 returns to the original standing posture that fills the gap between the fixing unit 12 and the conveyance unit 40 (FIG. 12).
Next, in the multi-function device 1 shown in FIG. 2 with the exterior cover 19 closed, the sheets are separated and sent one by one from the paper feed cassette 4 and the manual feed tray 5, and the sheets are registered on the conveying path 60 u for single-sided printing. Reach 7. The registration roller 7 sends the paper to the transfer unit 11 while correcting the oblique feeding of the paper and timing the toner image formed by the image forming unit 10.

In addition, based on image data from a controller (not shown), the multifunction device 1 controls the irradiation of the laser beam by the exposure unit 14. As a result, an electrostatic latent image of the original image is formed on the photosensitive drum of the image forming unit 10, and a toner image is subsequently formed on the photosensitive drum from the latent image and transferred to a sheet.
Thereafter, the sheet is fed toward the conveyance path 60d for single-sided printing while carrying an unfixed toner image, and the fixing unit 12 fixes the toner image. Next, the paper discharged from the fixing unit 12 is discharged to the paper discharge tray 18 through the discharge branch portion 13.

  When double-sided printing is performed in contrast to this single-sided printing, the paper discharged from the fixing unit 12 is pulled back to the conveyance path 70u side for double-sided printing immediately before being discharged to the paper discharge tray 18, and this paper is double-sided. The prints are merged into the supply junction 15 via the printing conveyance path 70d, and sent again toward the single-sided printing conveyance paths 60u and 60d. In this case, the toner image is transferred to the surface of the paper that has not been printed.

  As described above, according to the present exemplary embodiment, the apparatus main body 2 is provided with the conveyance paths 60u and 60d for single-sided printing and the conveyance paths 70u and 70d for double-sided printing. The fixed sheet can be sent out again toward the fixing unit 12 from the conveyance path 60d for single-sided printing to the conveyance paths 70u and 70d for double-sided printing. Further, when performing the jam processing or the like of the conveyance path 60u for single-sided printing, the user rotates the conveyance unit 40 with respect to the apparatus main body 2, and opens the conveyance path 60u for single-sided printing to the outside.

In addition, a conveyance guide 45 is provided in the conveyance path 70d for double-sided printing in the conveyance unit 40. The conveyance guide 45 of this embodiment is an apparatus main body for fixing the unit 12 for unit replacement, maintenance, and the like. When it is pulled out from 2, it retreats from the trajectory pulled out by the fixing unit 12.
Therefore, when the fixing unit 12 is replaced, the fixing unit 12 can be pulled out even in a closed state where the transport unit 40 does not rotate. As a result, breakage of the transport unit 40 can be prevented and workability improvement for the fixing unit 12 can be achieved.

  Further, when the unit side shaft portion 42 is on the side of the direction of opening the transport unit 40 with respect to the transport path 60u for single-sided printing, the trajectory drawn by the fixing unit 12 and the rotation trajectory of the transport unit 40 intersect at a deeper position. Therefore, the interference between the fixing unit 12 and the transport unit 40 becomes significant, and the transport unit 40 is more easily damaged. However, if the transport guide 45 is used, the problem can be reliably avoided.

Furthermore, the fixing unit rail 22 is configured so that the fixing unit 12 can be pulled out in the horizontal direction, and the workability with respect to the heavy fixing unit 12 is further improved.
Even when the heavy fixing unit 12 is pulled out, the conveyance guide 45 is restricted by the fixing unit rail 22 and remains in its retracted posture. Therefore, the operation of pulling out the fixing unit 12 in the horizontal direction can be performed quickly without being interrupted by the conveyance guide 45 at all.

Further, the conveyance guide 45 is divided from the conveyance unit 40 and is rotated with respect to the conveyance unit 40 around the guide side shaft portion 46. Even when the conveyance unit 40 is closed so as not to rotate, the fixing unit 12 is moved. It can be pulled out more reliably.
The present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the claims.

  The conveyance guide 45 of the above embodiment is configured to be rotatable with respect to the conveyance unit 40, but is not necessarily limited to this form. The conveyance guide of the present invention is used when the fixing unit 12 is pulled out. In addition, for example, by retracting into the transport unit 40, the locus of the fixing unit 12 can be withdrawn.

Further, the conveyance guide of the present invention may be integrally formed with the conveyance unit 40. This is because even when the conveyance guide is made of, for example, an elastic material and is integrally formed with the conveyance unit 40, the conveyance guide is brought into contact with the fixing unit 12 and falls down from the fixing unit, thereby preventing the conveyance unit from being damaged.
Further, in the above-described embodiment, an example in which the image forming apparatus is embodied in a multifunction machine is shown. However, the present invention is naturally applicable to a copying machine, a printer, and the like.

  In any of these cases, similarly to the above, the fixing unit can be pulled out even when the transport unit is closed.

1 MFP (image forming device)
2 Device body (image forming device body)
12 Fixing unit 22 Fixing unit rail (rail member)
30 Pressure roller (roller pair, one roller)
31 Fixing roller (roller pair)
40 transport unit 42 unit side shaft portion 45 transport guide 46 guide side shaft portion 60 transport path for single-sided printing 70 transport path for double-sided printing

Claims (5)

The roller has a pair of rollers for fixing an image to the recording material at the nip, and one of the rollers forming the nip is disposed between the conveyance path for single-sided printing and the conveyance path for double-sided printing of the recording material. A fixing unit configured to be removable from the image forming apparatus main body; and
The fixing unit has a conveyance path for single-sided printing and a conveyance path for double-sided printing, and rotates with respect to the image forming apparatus main body to open the conveyance path for single-sided printing to the outside. A transport unit that moves on a turning trajectory that intersects the pull-out trajectory;
Provided in the transport unit, and includes a transport guide that fills a gap between the fixing unit and the transport unit in the transport path for double-sided printing,
The conveyance guide is retracted from a trajectory of the fixing unit when the fixing unit is pulled out. The image forming apparatus according to claim 1,
The transport unit has a unit side shaft portion that is rotatably supported by the image forming apparatus main body at a position closer to the direction in which the transport unit is opened than a position where the transport path for single-sided printing is formed. An image forming apparatus. The image forming apparatus according to claim 1, wherein
An image forming apparatus comprising: a rail member on which the fixing unit is mounted and configured to be horizontally movable with respect to the image forming apparatus main body. The image forming apparatus according to claim 3, wherein
The image forming apparatus according to claim 1, wherein the conveyance guide retracted along with the drawing out of the fixing unit is in contact with the rail member and maintains its retracted posture. An image forming apparatus according to any one of claims 1 to 4,
The image forming apparatus, wherein the conveyance guide includes a guide-side shaft portion that is rotatably supported with respect to the conveyance unit.

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