JPH09146322A - Sheet carrying device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve operability in the case of removing a sheet accumulated in a sheet carrying path constituted of 1st and 2nd opening/closing parts by providing a specified click means. SOLUTION: When the 1st opening/closing part 35 is turned in a direction shown by an arrow (a) centering a hinge pin 37a with respect to a device main body 1 and is opened to an opening angler α deg., a stopper part 38b provided at the end of a hinge piece 38 abuts on and is locked on the side end 37b of a hinge piece 37 so as to restrain the turning operation of the 1st opening/ closing part 35 in the direction shown by the arrow (a). The opening angle αdeg.is set to an angle at which the jamming processing of a sheet S is easily performed without causing the 2nd opening/closing part 36 to abut on the device main body 1 when the 2nd opening/closing part 36 is opened in a direction shown by an arrow (b) with respect to the 1st opening/closing part 35. Thus, the 2nd opening/closing part 36 is opened to the 1st opening/closing part 35 without the fluctuation of the 1st opening/closing part 35, and the operability in the case of the jamming processing of the sheet is improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet conveying device equipped in an image forming apparatus such as a copying machine, a printer, and a facsimile machine, and an image forming apparatus having a double-sided or multiplex function.

[0002]

2. Description of the Related Art First, a first conventional example will be described. 2. Description of the Related Art Some image forming apparatuses such as a copying machine, a printer, and a facsimile machine have a plurality of sheet discharge paths for discharging a sheet having an image formed thereon. One of the typical devices is a multi-function digital copier having both a printer function and a facsimile function.

Below is a diagram of a multifunctional digital copying machine.
This will be described using 36 and FIG. 36 and 37 show the structure of a sheet discharge unit having a 3-bin sort. In FIG. 36,
The sheet discharge unit 301 of the copying machine main body 300 includes a first discharge path 302 for discharging the sheet S image-formed in the copy mode to the outside of the machine, and a sheet S image-formed in the printer mode or the facsimile mode. Second discharge path 303 for discharging the outside of the machine, and a third discharge path used in the sort mode,
Fourth discharge paths 304 and 305 are provided.

For example, when the sheet S stagnates in the fourth discharge path 305 in the sheet discharge section 301, the operation of the apparatus main body 300 automatically stops, and the stagnant sheet S cannot be recovered until it is removed. There is.

As shown in FIG. 37, the fourth discharge passage 305 provided in the sheet discharge portion 301 is a first discharge passage 305 which can be opened and closed with respect to the apparatus main body 300 via a hinge member (not shown).
The opening / closing portion 306 and the second opening / closing portion 307 configured to be opened / closed with respect to the first opening / closing portion 306 via a hinge member (not shown).

Then, when removing the sheet S stagnant in the fourth discharge path 305, the first opening / closing portion 306 is rotated with respect to the apparatus main body 300 in the direction of arrow a in FIG. Further, the second opening / closing portion 307 is opened with respect to the first opening / closing portion 306 by rotating in the direction of arrow b in FIG. 37 to open the fourth discharge passage 305, and inside the fourth discharge passage 305. The stagnant sheet S is removed.

Next, a second conventional example will be described. Figure
Reference numeral 38 shows the overall configuration of the image forming apparatus. This image forming apparatus is capable of double-sided copying in which both the front and back sides of one sheet S are copied, and multiplex copying in which the same side of one sheet S is copied multiple times. Is an electrophotographic copying machine having a front side discharge mode and a back side discharge mode.

Here, the structure for discharging or re-feeding the sheet S will be described. The sheet S on which the toner image formed by the image forming unit 400 is transferred and the toner is fixed by the fixing unit 401 is the front surface by single-sided copying. In the discharge mode, the sheet is fed to the pair of discharge rollers 403 by the transport roller 402, and is discharged onto a discharge tray (not shown) outside the apparatus with the image surface facing upward by the pair of discharge rollers 403. At this time, the flapper 404 installed at the branch portion is switched to the position of 404a.

Further, in the case of the one-sided copying in the back side discharge mode, the sheet S on which the fixing process of the toner image is finished is sent to the first re-feed path 405 by the carrying roller 402 so that the image side faces downward. At this time, the first flapper 404 is 40
Switched to position 4b. In addition, the second flapper
406 is switched to the position of 406a, and the sheet S is sent to the reversing path 408 by the pair of forward and reverse rotatable transport rollers 407 rotating in the direction of the arrow in FIG.

The trailing edge of the sheet S is the first flapper.
When a sensor (not shown) detects that the sheet S has passed 404, the conveyance roller pair 407 rotates (reverses) in the direction opposite to the direction of the arrow in FIG. 38, and the sheet S is sent to the discharge roller pair 403. The sheet is discharged onto a discharge tray outside the apparatus with the image surface facing downward by the discharge roller pair 403.
Here, the reverse path 409 of the sheet S for reverse discharge
Comprises a first refeed path 405 and a reverse path 408.

In the double-sided copy mode, the sheet S after the fixing process of the toner image is circulated with the image surface inside so that the sheet S is circulated by the conveying roller 402.
The sheet is sent to the sheet 3 and is once conveyed to the outside of the apparatus by the discharge roller 403. At this time, the first flapper 404
Has been switched to the 404a position.

The trailing edge of the sheet S is the first flapper.
When a sensor (not shown) detects that it has passed 404,
The first flapper 404 is switched to the position of 404b, and the discharge roller 403 rotates (reverses) in the direction opposite to the direction of the arrow in FIG. 38, whereby the sheet S is set to the first position with the image surface inside. After passing through the refeed path 405, the second flapper 406 is switched to the position of 406b and sent to the second refeed path 410.

In the case of the multiplex mode, the sheet S after the fixing process of the toner image is passed through the first re-feeding path 405 with the image on the outside by the conveying roller 402, and then the second re-feeding path 405. It is sent to the feeding path 410. At this time, the first
Flapper 404 is in position 404b and the second flapper 406 is
It is switched to the position of 406b respectively.

The sheet S sent to the re-feeding path 410 in the double-sided copying mode or the multi-copying mode is placed on the loading section (intermediate tray section) 411 provided in the middle of the second re-feeding path 410. When a predetermined number of sheets S are stacked and temporarily stacked on the sheet, the sheets are conveyed one by one from the placing section 411 to the transfer section.

[0015]

However, in the case of removing the sheet S stagnant in the fourth discharge path 305 in the above-mentioned first conventional example, the first opening / closing portion 306 is provided in the apparatus main body.
When opening with respect to 300 and opening the second opening / closing part 307 with respect to the first opening / closing part 306, the first opening / closing part 306 is free around the rotation center of the hinge member. Therefore, the first opening / closing unit 306 fluctuates, and the user opens the first opening / closing unit 306.
There is a problem that it is difficult to open / close the second opening / closing unit 307 unless the user holds and supports the second opening / closing unit 307.

Further, in the above-mentioned second conventional example, since the reversing path 409 for reversing and discharging the sheet S is provided below the placing section 411 which is the intermediate tray section, the structure is complicated and the apparatus is However, there was a problem such as an increase in size.

The present invention is to solve the above-mentioned problems.
A first object of the present invention is to provide a sheet conveying device having a first opening / closing part that can be opened / closed with respect to an apparatus main body and a second opening / closing part that can be opened / closed with respect to the first opening / closing part. Opening the first opening / closing part to the apparatus main body;
By providing click means for locking the first opening / closing part to the apparatus body at a position where the second opening / closing part can be opened / closed with respect to the first opening / closing part, Second
An object of the present invention is to provide a sheet conveying device having improved operability when removing a sheet stagnant in the sheet conveying path constituted by the opening / closing part and an image forming apparatus including the same.

A second object is to save space by reversing the sheet S at the time of reversing and discharging in the reversing path including the intermediate tray, and to reduce the size and simplification of the apparatus. is there.

A third object is to provide a curl removing means in the common path of the reversing path and the re-feeding path so that a single curl removing means can be used to form a photoconductor on the second surface. The purpose is to improve the separability from the drum and the mountability of the sheet S on the discharge tray during reverse discharge.

[0020]

A typical structure according to the present invention for achieving the above-mentioned object is to provide a first opening / closing section that can be opened and closed with respect to the apparatus main body and a first opening / closing section with respect to the first opening / closing section. In a sheet conveying device having a second opening / closing part that can be opened / closed, the first opening / closing part is opened with respect to the device main body,
A sheet conveying device, characterized in that click means for locking the first opening / closing part with respect to the apparatus main body is provided at a position where the second opening / closing part can be opened / closed with respect to the first opening / closing part. Is.

Since the present invention is configured as described above, the first opening / closing portion is locked to the apparatus main body at a position where the second opening / closing portion can be opened / closed with respect to the first opening / closing portion by the click means. By doing so, the operability when opening the second opening / closing part is good.

Further, another typical structure according to the present invention for achieving the above-mentioned object is to provide an intermediate tray portion for accommodating and storing a sheet having an image formed on one side for double-sided or multiple-image formation. In an image forming apparatus that has a reverse discharge mode in which a single-sided image-formed sheet is reversed and discharged, a reverse path for reversely discharging the sheet and a re-feeding path in which the intermediate tray unit is disposed are provided. It is characterized in that it is configured in common.

In the above structure, by performing the reversal at the time of discharging the back surface of the sheet S in the reversal path including the intermediate tray portion, it is not necessary to separately provide the reversal path and the re-feeding path.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a sheet conveying device and an image forming apparatus according to the present invention will be specifically described below with reference to the drawings.

First Embodiment First, referring to FIGS. 1 to 4, a sheet carrying device according to the present invention and a first embodiment when applied to a multi-function digital copying machine as an example of an image forming apparatus equipped with the same. The form will be described. FIG. 1 is an explanatory cross-sectional view showing the overall configuration of an image forming apparatus equipped with a sheet conveying device according to the present invention, and FIG. 2 is a perspective view showing a state in which a sheet discharging portion of the sheet conveying device according to the present invention is opened. FIG. 4 is a plan explanatory view showing a state in which a sheet discharging unit of the first embodiment of the sheet conveying device according to the present invention is opened, and FIG. 4 is a cross-sectional view showing the configuration of the click means of the first embodiment shown at C in FIG. It is a figure.

First, the overall structure of an image forming apparatus equipped with the sheet conveying apparatus according to the present invention will be described with reference to FIG. In FIG. 1, an image reading unit A for reading image information of a document is disposed at an upper portion of the image forming apparatus main body 1, and an image forming unit B for recording an image on a sheet S according to the image information is disposed below the image reading unit A. Is arranged.

Below the image forming section B, a sheet cassette 2a for accommodating a sheet S made of paper, synthetic resin or the like,
2b is arranged, and the sheet S fed by the pickup rollers 3a and 3b serving as sheet feeding means is
The sheet is separated and fed one by one by a sheet separating unit (not shown), and is conveyed through a sheet feeding path 4 to a position where an electrophotographic photosensitive drum 5 serving as an image forming unit provided in the image forming unit B faces. .

Here, when the image forming apparatus main body 1 is in the copy mode, the image information of the document set on the document table 6 is read by the image reading means 8 by driving the scanning optical system 7.

Then, the laser scanner 9 emits a laser beam L based on the image information read by the image reading means 8, the surface is uniformly charged by the charger 12, and it rotates in the clockwise direction in FIG. A reflection mirror on the surface of the photosensitive drum 5.
A laser beam L is scanned through 10 and 11 to form an electrostatic image, and toner is supplied from the developing device 13 to the electrostatic image to form a toner image, which is visualized.

The sheet S fed from the sheet cassettes 2a and 2b is arranged by the registration roller pair 14 in synchronism with the rotation of the photosensitive drum 5 and the photosensitive drum 5 and a position facing the photosensitive drum 5. The toner image formed on the photosensitive drum 5 is transferred to the sheet S by the transfer charging device 15 while being conveyed to the transfer charging device 15.

The sheet S on which the image has been transferred is a conveyor belt.
16 and sent to the fixing device 17 where the fixing device 17
The toner image is fixed on the sheet S by being heated and pressed by the fixing roller 17a and the pressure roller 17b provided on the sheet.

When the image forming apparatus main body 1 is in the printer mode or the facsimile mode, the laser scanner 9 is used.
Emits a laser beam L based on image information sent from an external computer or a facsimile machine of the other party, and a toner image is formed and fixed on the sheet S in the same manner as described above.

A sheet discharging unit 18 is provided on the downstream side of the fixing device 17 in the sheet conveying direction (hereinafter, simply referred to as “downstream side”).
Three bins 19, 20, 21 which are sheet ejection trays via
Is provided. Here, as an example of the discharging operation of the sheet S by the sheet discharging unit 18, the image-formed sheet S is
The three-bin sort mode will be described in which the sheets are sorted into three bins 19, 20, and 21 in order, discharged, and placed.

First, select from the sheet cassettes 2a and 2b
First sheet S that has been unreeled ₁Is
An image is formed, and the first discharge provided in the sheet discharge section 18
It is discharged and placed on the bin 19 through the path 22. in this case,
The flapper 24 provided in the sheet discharge section 18 is the first discharge path.
22 is opened, and the first sheet S₁Is also
Transported by a pair of discharge rollers 23 provided in the sheet discharge unit 18.
Is done.

The second sheet S 2 conveyed after the _first sheet S ₁ is formed with an image in the same manner as described above, and then the _second sheet S ₂ provided in the sheet discharge unit 18 is provided. After passing through the path 25, the sheet is discharged and placed on the bin 20 through the third discharging path 26 also provided in the sheet discharging section 18.

In this case, the flapper 24 is positioned with the second discharge path 25 open, and the flapper 27 provided in the sheet discharge section 18 is positioned with the third discharge path 26 open. The sheet S ₂ of the first sheet is conveyed by a pair of discharge rollers 28, 29, 30 also provided in the sheet discharge section 18.

[0037] The third sheet S ₃ which is conveyed subsequent to the second sheet S _2, after an image is formed in the same manner as described above, after a second discharge path 25, a sheet discharge It is discharged and placed on the bin 21 through a fourth discharge passage 31 provided in the section 18.

In this case, the flapper 24 is positioned with the second discharge path 25 open, the flapper 27 is positioned with the fourth discharge path 31 open, and the third sheet S ₃ is a sheet. The sheet is conveyed by discharge roller pairs 28, 29, 32, 33 provided in the discharge section 18.

As described above, the fourth and subsequent sheets S
Are sequentially sorted into three bins 19, 20, and 21 to be discharged and placed.

Here, when the sheet S is stagnated in the first, second, third and fourth discharge paths 22, 25, 26 and 31, the sheet discharge section 18 is installed in the apparatus as will be described later in detail. The first, second, third, and fourth discharge paths 22, 25, 26, 31 are opened to the main body 1 to remove the stagnant sheet S.

For example, when the sheet S is stagnant in the fourth discharge path 31 in the sheet discharge section 18, the operation of the image forming apparatus main body 1 is automatically stopped, and the stagnant sheet S can be recovered unless it is removed. It's gone.

The fourth discharge path provided in the sheet discharge section 18
As shown in FIGS. 2 and 3, reference numeral 31 is a first opening / closing portion configured to be opened / closed with respect to the apparatus main body 1 via a hinge member 34.
35, and a second opening / closing portion 36 that can be opened / closed with respect to the first opening / closing portion 35 via a hinge member (not shown).

When the sheet S stagnated in the fourth discharge path 31 is removed, the first opening / closing section 35 is attached to the apparatus main body 1
2 in the direction of arrow a in FIG.
The opening / closing portion 36 of the sheet is rotated relative to the first opening / closing portion 35 in the direction of the arrow b in FIG. 2 to open to open the fourth discharge path 31, and the sheet stagnant in the fourth discharge path 31. It is possible to remove S.

Next, the click means which is a feature of the present invention will be described with reference to FIGS. 3 and 4. As shown in FIG. 3, the sheet discharge unit 18 is a hinge member with respect to the apparatus body 1.
A first opening / closing part 35 that can be opened / closed by 34, and the first opening / closing part
Second that can be opened and closed by a hinge member not shown for 35
The first and second opening / closing portions 35 and 36 are a pair of discharge rollers serving as the above-described sheet conveying means.
It is configured to have a sheet guide or the like for guiding the sheet S in the 32, 33 and the fourth discharge path 31.

The hinge member 34 is a hinge pin in which a hinge piece 37 fixed to the apparatus body 1 side and a hinge piece 38 fixed to the first opening / closing portion 35 side are fixed to the hinge piece 37 and erected. 37a is fitted and engaged with a hole 38a formed in the hinge piece 38 and having an inner diameter corresponding to the outer diameter of the hinge pin 37a, and the first opening / closing part 35 (first Two
(Including the opening / closing section 36 of FIG. 3) with respect to the apparatus main body 1 as indicated by arrow
It is supported so that it can rotate in any direction.

When the first opening / closing portion 35 is rotated in the direction of arrow a in FIG. 3 around the hinge pin 37a with respect to the apparatus main body 1 to open up to the opening angle α ° as shown in FIG. The stopper portion 38b provided at the end of the piece 38 is a hinge piece 37.
The side opening portion 37b of the first opening / closing portion 35 is brought into contact with and locked by the side end portion 37b of the first opening / closing portion 37b so as to prevent the first opening / closing portion 35 from rotating in the direction of arrow a in FIG.

The opening angle α ° is set to the second opening / closing part 36.
2 is opened with respect to the first opening / closing part 35 in the direction of the arrow b in FIGS. 2 and 3, the second opening / closing part 36 does not come into contact with the apparatus main body 1 and the jamming of the sheet S can be easily performed. Is set to.

As shown in FIG. 4, at a predetermined position on the back surface of the hinge piece 37 fixed to the apparatus main body 1 side, a leaf spring 39 as an elastic member holds the hinge piece 37 and at a predetermined position of the hinge piece 37. A click ball 40 is provided which is a click member capable of projecting / depressing from a hole 37c having a diameter of. The click ball 40 is constantly urged in the direction of arrow c (upward direction) in FIG. 4 by the elastic force of the leaf spring 39.

The hole 37c formed in the hinge piece 37 has a diameter smaller than the diameter of the click sphere 40 and has a tapered surface that spreads downward. The hole 37c and the leaf spring 39 stabilize the click sphere 40. Then, it can be held so that it can be projected / retracted from the hole 37c.

Further, at a predetermined position of the hinge piece 38 corresponding to the click ball 40, there is formed a positioning hole 38c having a predetermined diameter into which the spherical upper portion of the click ball 40 can fit. The positioning hole 38c has a diameter smaller than that of the click sphere 40, and has a size corresponding to the diameter of the hole 37c.

With the above configuration, the first
In the state in which the opening / closing part 35 is closed, the hinge piece 38 is in contact with the click sphere 40, and the click sphere 40 resists the elastic force of the leaf spring 39 in the direction opposite to the arrow c in FIG. 4 (downward). The hinge piece 37 is urged by and is depressed to a position corresponding to the upper surface 37d of the hinge piece 37.

The first opening / closing section for the apparatus main body 1
When 35 is rotated in the direction of arrow a in FIG. 3 around the hinge pin 37a, the hinge piece 38 that moves integrally with the first opening / closing portion 35 moves while contacting the click ball 40, and the first opening / closing portion 35 Can be easily opened up to the opening angle α ° shown in FIG.

Then, when the first opening / closing part 35 reaches the opening angle α ° shown in FIG. 3, the positioning hole 38c of the hinge piece 38 reaches the position corresponding to the click ball 40, and the click ball 40 leaves the leaf spring. The elastic force of 39 urges the click ball 40 in the direction of arrow c (upward direction) of FIG.
The first opening / closing part 35 is engaged with the device main body 1 at an opening angle α °.

As a result, the first opening / closing portion 35 does not sway, and as shown in FIG. 2, the second opening / closing portion 36 can be easily opened with respect to the first opening / closing portion 35. The sheet S can be jammed by opening the discharge passage 31 of No. 4.

After the jam processing, the second opening / closing portion 36 is held in the state where the first opening / closing portion 35 is locked as described above.
After closing the first opening / closing portion 35 with respect to the first opening / closing portion 35, the first opening / closing portion 35 is rotated against the elastic force of the leaf spring 39 in the direction opposite to the arrow a in FIG. Click sphere 40 is a leaf spring
4 is pushed in the direction opposite to the arrow c in FIG. 4 against the elastic force of 39, and is detached from the positioning hole 38c, and is depressed at a position corresponding to the upper surface 37d of the hinge piece 37. In this state, the first opening / closing portion 35 is rotated with respect to the apparatus main body 1 in the direction opposite to the arrow a in FIG.
The first opening / closing portion 35 can be closed with respect to the apparatus main body 1.

Therefore, according to the present invention, it is not necessary for the user to grasp and support the first opening / closing portion 35 as in the above-mentioned conventional example, and the second opening / closing portion 36 is opened / closed with a relatively simple structure. It is possible to improve the operability to perform, and it is possible to improve the operability during the jam processing.

In the above embodiment, the click ball 40 is provided in the hinge piece 37 on the apparatus body 1 side, and the positioning hole 38c corresponding to the click ball 40 is provided in the hinge piece 38 on the first opening / closing part 35 side. However, as another configuration, the click ball 40 is provided in the hinge piece 38 on the first opening / closing part 35 side, and the positioning hole 38c corresponding to the click ball 40 is provided in the hinge piece 37 on the apparatus main body 1 side. Even if it is, the same effect can be obtained.

In the above embodiment, the click sphere 40 is used as the click member, but the click member need not be limited to a sphere, and a hemispherical member or a member having a curved surface may be used as the end of the leaf spring 39. It may be configured to be fixed to the portion, or further, a coil spring or another elastic member may be provided instead of the leaf spring 39 configured to allow the click member to project / recess.

Second Embodiment Next, a second embodiment of the sheet conveying device according to the present invention and the image forming apparatus having the same will be described with reference to FIGS. 5 and 6. FIG. 5 is an explanatory plan view showing a state in which the sheet discharging portion of the second embodiment of the sheet conveying device according to the present invention is opened, and FIGS. 6 (a) to 6 (c).
FIG. 6 is a cross-sectional explanatory view showing a configuration of a click means of a second embodiment shown in a D part in FIG. The same components as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted.

5 and 6, a surface cam 37e serving as a surface cam portion is provided at a predetermined position of the hinge piece 37 fixed to the apparatus body 1 side, and the hinge piece 38 corresponding to the surface cam 37e. At the predetermined positions of the hinge pieces 38, there are provided bent portions 38f and 38g, which are first and second engaging portions formed by bending and bending the hinge piece 38, and are provided adjacent to the bent portions 38f and 38g. 38d and 38e are formed.

The surface cam 37e is fitted in the holes 38d, 38e, and the curved portions 38f, 38g, the holes 38d, 38e, and the surface cam 37e are predetermined so that they can abut and engage with the curved portions 38f, 38g. It is composed of dimensions.

With the above construction, when the first opening / closing portion 35 is in the closed state with respect to the apparatus main body 1, as shown in FIG. 6 (a), the surface cam 37e is fitted into the hole 38d and cut. Music section
38f is in abutting engagement with 38f, and at this time, the gravity of the first opening / closing part 35 (including the second opening / closing part 36) acts in the direction of arrow t in FIG. The portion 35 is locked to the apparatus body 1.

Next, against the gravity of the first opening / closing part 35 (including the second opening / closing part 36), the first opening / closing part 35 with respect to the apparatus main body 1 is centered around the hinge pin 37 a. When the first opening / closing part 35 starts to open by rotating in the direction of the arrow a, the first opening / closing part 35
The hinge piece 38, which is integrally formed with, is indicated by an arrow d in FIG.
Moving in the direction, the bent portion 38f rides on the surface cam 37e, and further the first opening / closing portion 35 is attached to the hinge pin 37a with respect to the apparatus main body 1.
When it is opened by rotating in the direction of arrow a in FIG.
As shown in (c), the surface cam 37e abuts and engages with the curved portion 38g and fits into the hole 38e. At this time, the first opening / closing part
The gravity of 35 (including the second opening / closing portion 36) acts in the direction of the arrow t in FIG. 6C, and the first opening / closing portion 35 is locked to the apparatus body 1.

At this point, the first opening / closing part 35 is opened to the opening angle α ° shown in FIG. 5, and like the first embodiment,
The stopper portion 38b provided on the hinge piece 38 is brought into contact with and locked to the side end portion 37b of the hinge piece 37, so that the pivotal movement of the first opening / closing portion 35 is suppressed.

As a result, the first opening / closing part 35 does not sway, and as shown in FIG. 2, the second opening / closing part 36 can be easily opened with respect to the first opening / closing part 35. The sheet S can be jammed by opening the discharge passage 31 of No. 4.

After the jam is removed, the second opening / closing part 36 is locked with the first opening / closing part 35 being locked as described above.
Is closed with respect to the first opening / closing part 35, and the first opening / closing part 35 is attached to the device body 1 by gravity of the first opening / closing part 35 (second opening / closing part 35).
(Including 36), the surface cam 37e rides on the curved portion 38g when it rotates in the direction opposite to the arrow a in FIG. 5 (FIG. 6B).
5), when the first opening / closing part 35 is further rotated in the direction opposite to the arrow a in FIG. 5, the surface cam 37e abuts and engages with the curved part 38f and is fitted and locked in the hole 38d. .

As described above, the hinge piece 38 on the side of the first opening / closing portion 35 has the gravity (second opening / closing portion 36) of the first opening / closing portion 35.
(Also including) is always pressed against the hinge piece 37 on the apparatus body 1 side.

Therefore, according to the present invention, there is no need for the user to grip and support the first opening / closing portion 35 as in the above-described conventional example, and the second opening / closing portion 36 can be opened / closed with a relatively simple structure. It is possible to improve the operability to perform, and it is possible to improve the operability during the jam processing.

Further, in this embodiment, since the surface cam 37e and the bent portions 38f and 38g are integrally formed on the hinge pieces 37 and 38, respectively, the cost can be reduced without increasing the number of parts. I can.

In the above embodiment, the surface cam 37e is provided on the hinge piece 37 on the apparatus main body 1 side, and the curved portions 38f, 38g and the holes 38d, 38e corresponding to the surface cam 37e are formed in the first opening / closing portion 35.
Although it is provided on the side hinge piece 38, as another configuration,
A surface cam is provided on the hinge piece 38 on the side of the first opening / closing portion 35, and a bent portion and a hole corresponding to the surface cam are provided on the hinge piece on the apparatus body 1 side.
The same effect can be obtained even if it is provided in 37.

In the first and second embodiments, the stopper portion 38b is provided on the hinge piece 38 on the first opening / closing portion 35 side. However, as another configuration, the hinge piece on the apparatus main body 1 side is provided.
A stopper portion is provided on 37, and when the first opening / closing portion 35 is opened with respect to the apparatus main body 1 by a predetermined angle, the stopper portion abuts on the hinge piece 38 and is locked, and the first opening / closing portion 35 is rotated. It may be configured to regulate the dynamic operation.

[Third Embodiment] Next, a third embodiment of the image forming apparatus according to the present invention will be described with reference to FIG. In FIG. 7, the image forming apparatus includes a double-sided copy in which both sides of one sheet S are copied and one sheet S is copied.
It is an electrophotographic copying machine capable of performing multiple copying in which the same side is duplicated a plurality of times and having a front side discharge mode and a back side discharge mode for single sided copying.

This image forming apparatus is equipped with sheet cassettes 50 and 51 capable of accommodating a plurality of sheets S so that the sheets S can be selectively fed from the sheet cassettes 50 and 51 to the transfer section. Has become. The sheets S placed and stored in the sheet cassettes 50 and 51 are moved to the uppermost sheet S by the feeding rollers 52 and 53 which rotate in the arrow direction of FIG.
It is paid out sequentially from.

The sheets S fed by the feeding rollers 52, 53 are separated one by one by the pair of separating rollers 54, 55 which rotate in the direction of the arrow in FIG. 7, and are fed to the pair of registration rollers 56 whose rotation is stopped. To be done. Separation roller pair 5
When the leading edge of the sheet S fed by 4, 55 hits the nip of the registration roller pair 56, a predetermined loop is formed and the skewed state is corrected.

After that, the sheet S with the skewed state corrected
7 is rotated by the registration roller pair 56 that starts rotating in the arrow direction in FIG. 7 at the timing of aligning the position with the toner image on the photosensitive drum 57 rotating in the arrow direction in FIG. It is sent to the transfer section between 58,
Here, the toner image on the photosensitive drum 57 is transferred onto the sheet surface of the sheet S by the transfer charger 58.

In this image forming apparatus, the image of the original 60 set on the platen glass 59 is changed to the illumination lamp.
The image is projected onto the photoconductor drum 57 rotating in the direction of the arrow in FIG. 7 by the optical system including 61, the reflection mirrors 62a to 62f, the zoom lens 63 and the like. The electrostatic latent image formed on the photoconductor drum 57 by this is visualized by the color toner supplied from the first developing device 64 or the black toner supplied from the second developing device 65. It becomes a toner image.

The sheet S on which the toner image has been transferred at the transfer portion is fixed by a conveying device (first sheet conveying path) 66 including a plurality of conveying rollers 66a, 66b, 66c.
The toner image is sent to the sheet 67 and is fixed on the sheet surface of the sheet S by the fixing device 67.

The image-fixed sheet S is discharged or re-fed. Next, the discharge or re-feed of the sheet S will be described. The sheet S after the fixing process of the toner image is sent to the discharge roller pair 69 by the conveying roller 68 in the case of the one-sided copying in the front surface discharge mode, and the discharge roller pair 69 causes the image surface to face the outside of the apparatus. Is discharged onto a discharge tray (not shown). At this time, the flapper 70 installed at the branch portion is switched to the position of 70a.

Further, in order to carry out the back side discharge mode in single-sided copying, in the present embodiment, it is possible to perform forward / reverse rotation between the first re-feeding path 71 and both sides, and the placing section (intermediate tray section) 72a at the time of multiple copying. A different transport roller pair 73 is provided. For this reason, in the case of the one-sided copying in the back side discharge mode, the sheet S on which the fixing process of the toner image is finished is sent to the first re-feed path 71 by the carrying roller 68 so that the image side faces downward. At this time, the first flapper 70 is switched to the position 70b.

The sheet S is sent to the intermediate tray 72 by the pair of conveying rollers 73 rotating in the direction of the arrow in FIG.
When a sensor (not shown) detects that the rear end of the sheet S has passed the first flapper 70, the pair of conveyance rollers 73 rotates (reverses) in the direction opposite to the arrow direction of FIG. The discharge roller 69 is sent to the roller 69.
Is discharged onto the discharge tray outside the machine with the image surface facing downward. Here, the reversing path 74 of the sheet S for reversing and discharging includes the first re-feeding path 71 and the intermediate tray section 72.

In the double-sided copy mode, the sheet S after the fixing process of the toner image is sent to the discharging roller pair 69 by the conveying roller 68 to circulate with the image surface inside, and is discharged by the discharging roller 69. Once transported to the outside of the machine on the discharge tray. At this time, the first flapper 70 is switched to the position 70a.

The trailing edge of the sheet S is the first flapper.
When a sensor (not shown) detects passing through 70, the first flapper 70 is switched to the position 70b, and the discharge roller pair 69 rotates (reverses) in the direction opposite to the arrow direction in FIG. The sheet S is sent to the second refeed path 75 through the first refeed path 71 with the image surface inside.

Further, in the case of the multiplex mode, the sheet S which has been subjected to the fixing process of the toner image passes through the first re-feeding path 71 with the image on the outside by the conveying roller 68 and passes through the second re-feeding path 71. It is sent to the feeding path 75. At this time, the first flapper 70 is switched to the position 70b.

The sheet S sent to the refeeding path 75 in the double-sided copying mode or the multiplex copying mode is placed on the loading section 75 (intermediate tray section) 72a provided in the middle of the second refeeding path 75. When a predetermined number of sheets S are temporarily placed on the sheet stacking device, the sheets S are conveyed one by one from the placing section 72a to the transfer section.

The sheet S sent to the re-feed path 75
In the stacking section 72a, the upper rollers S are conveyed by the pair of conveying rollers 76 and 77 so that the leading edges of the higher-order sheets S that are sent later are stacked on the upstream side by a predetermined amount.

Then, the sheets S stacked on the mounting portion 72a
Are sequentially conveyed to the transfer portion from the lowermost sheet S having the leading edge on the most downstream side. In this case, the sheet S bundle is conveyed downstream by the pair of conveying rollers 76 and 77, and the lowermost sheet S is conveyed. Only the sheet S is separated from the other sheets S by the separation flapper 79 rotatable about the support shaft 78.

Then, the separated lowermost sheet S is conveyed again to the transfer portion by the conveying roller pair 80. The re-feeding path 81 for double-sided copying and multiple copying includes a first re-feeding path 71, an intermediate tray section 72, and a re-feeding path 82.

As described above, in the present embodiment, since the reversing path for reversing and ejecting the sheet includes the double-sided and the intermediate tray used at the time of stacking, and the common tray is used, the space is saved and the apparatus is greatly reduced. Miniaturization is possible. Further, since parts such as the flapper and the guide plate can be reduced, effects such as cost reduction and improvement of assemblability can be obtained.

[Fourth Embodiment] Next, a fourth embodiment of the image forming apparatus according to the present invention will be described with reference to FIGS. FIG. 8 shows the overall configuration of the image forming apparatus according to the fourth embodiment. In this embodiment, in place of the forward / reverse transport roller pair 73 of the image forming apparatus according to the third embodiment described above, a forward / reverse roll curl removing roller-equipped transport roller pair 83 is provided. is there.

As shown in FIG. 9, this conveying roller pair 83 has two driven rollers 83 whose outer diameter is straight to the roller 83a.
b and 83c are biased by a biasing means (not shown) at an appropriate angle β, and the seat S is indicated by an arrow in FIG.
It is curled in the direction of 84.

In the structure of the third embodiment, the conveying roller pair 83 is provided in the common path of the reversing path 74 used for discharging the back surface and the double-sided and re-feeding path 81 used for multiplexing. Therefore, the sheet S can be curled in the direction of the arrow 84 in FIG. 9 by one curl removing means, that is, the pair of conveying rollers 83. And multiple), the separability from the photoconductor drum 57 can be improved.

[Fifth Embodiment] Next, a fifth embodiment of the image forming apparatus according to the present invention will be described with reference to FIG. In the fourth embodiment described above, instead of the driven rollers 83b and 83c in the pair of conveying rollers with curl removing rollers 83, driven rollers 85b and 85c whose both ends are appropriately thicker than the central portion are used as shown in FIG. As a result, it is possible to add the stiffness 86 in the sheet S conveying direction as shown in FIG.

Therefore, as compared with the above-described fourth embodiment, the curl of the sheet S is corrected, and the mountability at the time of ejecting the back surface and the separability from the photosensitive drum at the time of image formation on the second surface can be improved. It is a thing.

[Other Embodiments] Next, embodiments of other configurations equipped in each of the image forming apparatuses will be described with reference to FIGS. 11 to 35.

[Sixth Embodiment] A sixth embodiment of another configuration equipped in each image forming apparatus will be described below with reference to FIGS.
This will be described with reference to FIG. FIG. 11 is a cross-sectional explanatory view of the image forming apparatus in the sixth embodiment, FIG. 12 is a side cross-sectional explanatory view showing the constitution of the conveyor belt, and FIG. 13 is a block diagram showing a main part of a control system of the sheet conveying apparatus of the sixth embodiment. FIG. 14, FIG. 14 and FIG. 15 are flowcharts of the control system in the sheet conveying apparatus of the sixth embodiment, FIG. 14 is a flowchart showing a sequence when a sheet is fed from a manual feeding port, and FIG. 6 is a flow chart showing a sequence in the case where is fed.

In FIG. 11, 101 is a sheet cassette for accommodating sheets S. A sheet size sensor 128 shown in FIG. 13 is provided in the sheet cassette 101, and a sheet size sensor 128 detects a sheet S when a sheet S of a predetermined size is accommodated in the sheet cassette 101 and attached to the apparatus main body C101. The size code of S is the device body C101
It is adapted to be transmitted to the control unit 129 shown in FIG.

Reference numeral 102 denotes a pickup roller having a half-moon shape in cross section for feeding out the sheet S stored in the sheet cassette 101. Reference numeral 126 is a separation claw arranged above the sheet feeding port of the sheet cassette 101, and the tip corners of the sheet S fed out by the pickup roller 102 are engaged with the separation claw 126 so that only the uppermost sheet S is conveyed. Are fed to the sheet path 130 one by one after overcoming the separation claw 126.

Reference numeral 103 denotes a pair of intermediate rollers that conveys the sheet S fed from the sheet cassette 101 further downstream. The intermediate roller pair 103 has a built-in clutch (not shown) so that the intermediate roller pair 103 can be started / stopped at a predetermined timing according to a command from the control unit 129 shown in FIG.
When the sheet is stopped, the pair of intermediate rollers 103 are fixed while sandwiching the sheet S, and function as sheet waiting means for waiting the conveyance of the sheet S at the position of the pair of intermediate rollers 103.

A pre-feed sensor 105 is arranged downstream of the intermediate roller pair 103 in the sheet conveying direction (hereinafter, simply referred to as “downstream side”). Pickup roller 10
When 2 rotates 101 or 102 times, the sheet S fed from the sheet cassette 101 is fed to the vicinity of the pre-feed sensor 105.

The pre-feed sensor 105 detects the leading edge of the sheet S fed from the sheet cassette 101. And when the image development of the print controller is delayed,
Based on the sheet leading edge detection signal of the pre-feed sensor 105, the control unit 129 shown in FIG. 13 controls the intermediate roller pair 103 to stop and temporarily hold the sheet S at the position of the intermediate roller pair 103.

Reference numeral 104 denotes a process cartridge 10 which serves as an image forming means for the sheet S conveyed by the intermediate roller pair 103.
9 is a pair of registration rollers that conveys to the image forming unit in which the electrophotographic photosensitive drum 108 is arranged, and the sheet is detected by the registration sensor 106 serving as the 101st sheet detection unit arranged in the vicinity of the registration roller pair 104 and on the downstream side. When the tip of S is detected, the photosensitive drum 108 is detected based on this detection information.
The sheet S is conveyed in synchronization with the rotation of the sheet.

A laser scanner 107 is provided above the process cartridge 109.
7 exposes the surface of the uniformly charged photosensitive drum 108 to light to form a latent image. The latent image is a process cartridge
The toner image is visualized as a toner image by the developing process performed inside the printer 109, and the transfer sensor 110 is used by the transfer sensor 110.
By 6, the toner image is transferred onto the sheet S conveyed in synchronization.

The sheet S to which the toner image has been transferred is placed on the conveyor belt 120 serving as a sheet conveying means having no means for holding the sheet S, and is conveyed to the fixing device 111. Then, the toner image transferred onto the sheet S is fixed by the fixing device 111, and then discharged onto the discharge tray 113 arranged above the apparatus main body C101 by the discharge roller pair 112.

The fixing device 111 is a flat ceramic heater.
114, a film guide 115 that supports the ceramic heater 114, and a metal stay that reinforces the film guide 115.
A fixing roller 127 composed of a film 117 and a film 117 and a pressure roller 118 are provided.
The discharge sensor 119, which serves as a sheet detection unit for detecting the passage of the sheet S through the fixing unit, is configured.

As described above, driving rollers 121 and 122 are used to stretch between the nip portion A101 between the photosensitive drum 108 and the transfer roller 110 and the nip portion B101 between the fixing roller 127 and the pressure roller 118. The transport belt 120 is provided. The path length L101 of the transport path formed between the nip portion A101 and the nip portion B101 by the transport belt 120.
The sheet S having a shorter length in the sheet conveying direction (hereinafter, simply referred to as “length”) can be conveyed.

As shown in FIG. 12, the conveyor belt 120 is provided with a plurality of protrusions 120a on the outer surface of the conveyor belt 120 at predetermined intervals, and the protrusions 120a contact the rear end of the sheet S so that the sheet S By pushing S, the conveying force is applied to the sheet S. The distance between the protrusions 120a is the sheet S to be used.
It is set according to the length of.

The transport belt 120 is particularly advantageous for transport when the length of the sheet S in the sheet transport direction (hereinafter simply referred to as “length”) is relatively short and cannot be nipped by a pair of transport rollers arranged in series. is there. In addition, when the conveyance path is relatively long, it is also advantageous when the sheet S is conveyed to a long distance with one simple configuration. By using this, the configuration of the apparatus is simple and the cost is reduced. You can

Due to its structure, the transport belt 120 has the sheet S.
Since there is no means for sandwiching the sheet S, the length of the sheet S among the sheets S of various sizes used is equal to that of the photosensitive drum 108.
Nip A101 between the transfer roller 110 and the fixing roller 12
7 is shorter than the conveyance path length L101 between the nip portion B101 of the pressure roller 118 and the nip portion B101, the sheet S is conveyed only by the conveyance belt 120 that does not have a nipping means for nipping the sheet S, and the sheet S is The weight of the sheet S and the sheet S
It is transported while being restricted only by the frictional force between the transport belt 120 and the transport belt 120.

Reference numeral 123 designates a manual feeding roller which serves as a sheet feeding means for feeding the sheet S manually fed from the manual feeding port, and a plurality of sheets S stacked on the middle plate 124 are sequentially separated by the separation pad 125. Sheet path one by one while separating
It is supposed to be sent to 131.

The sheet S fed by the manual feeding roller 123 is conveyed through the sheet path 131, is located downstream of the pre-feed sensor 105, and is in registration roller pair 104.
On the upstream side, the sheet S merges with the sheet path 130 for transporting the sheet S from the sheet cassette 101, and is transported to the image forming unit in which the process cartridge 109 is arranged as described above, and an image is formed through the electrophotographic process. Is
The image is fixed by the fixing device 127 and is discharged to the discharge tray 113.

When the sheet is fed by the manual feeding roller 123, the sheet S fed from the above-mentioned sheet cassette 101 is used.
As described above, there is no configuration in which the sheet S is detected by the pre-feed sensor 105, is sandwiched and fixed by the intermediate roller pair 103, and the sheet S temporarily stands by. In this case, the sheet S is stopped by the manual feeding roller 123 and the sheet S 124 Standing on board.

The above-mentioned control of the electrophotographic process is performed by the engine controller provided in the control unit 129 shown in FIG. On the other hand, the image code data sent from the host computer is expanded into bit data necessary for recording an image by the print controller provided in the control unit 129 and transmitted to the engine controller.

Next, the structure of the control system of the sheet conveying apparatus will be described with reference to FIGS. First, the configuration of the main part of the control system of the sheet conveying apparatus will be described with reference to FIG. FIG.
In the above, the detection information detected by the registration sensor 106, the discharge sensor 119, the pre-feed sensor 105, and the sheet size sensor 128 is transmitted to the control unit 129, and predetermined arithmetic processing is performed.

The control unit 129 is provided with a C101 PU serving as a central information processing unit and a storage unit arranged in parallel with the C101 PU. The size code information from the sheet size sensor 128,
Alternatively, the length of the sheet S is detected by calculating the detection information of the registration sensor 106 and the discharge sensor 119 or the detection information of the front and rear edges of the sheet S detected by the registration sensor 106 and the conveyance speed information of the sheet S. It has a length detecting means. The length detecting means determines whether or not the sheet S fed is shorter than the transport path length L101.

Further, it is detected that delay jam has occurred in the conveyed sheet S by calculating the detection information obtained by detecting the presence or absence of the sheet S by the registration sensor 106 and the discharge sensor 119 and the conveyance speed information of the sheet S. It has a jam detecting means.

Further, the control unit 129 is connected with a jam notifying means 132 for notifying the user of the occurrence of a delayed jam by a display, an alarm, etc., and the jam notifying means based on the detection information detected by the jam detecting means. 132 is activated to notify the user of the occurrence of a delay jam.

The control unit 129 is also equipped with a timer function, which starts a timer from a predetermined time to measure times T ₁ , T ₂ , T ₃ , T ₄ , T ₅ which will be described later, and Jam notification means 132, according to the passage of time such as
Predetermined control operations are performed on the intermediate roller pair 103, the conveying roller pair 104, the pickup roller 102, the manual feeding roller 123, and the like.

Next, the sheet feeding operation will be described in detail with reference to FIGS. 14 and 15. FIG. 14 is a flowchart showing a sequence when the sheet S is fed from the manual feed port by the manual feed roller 123, and FIG. 15 is a sheet cassette 101.
6 is a flowchart showing a sequence when the sheet S is fed from the pickup roller 102.

First, the case where the sheet S is fed from the manual feed port by the manual feed roller 123 will be described with reference to FIG. When the sheet S is fed from the manual feed port by the manual feed roller 123, the size of the sheet S cannot be recognized unless the sheet S is fed into the apparatus main body C101.

Therefore, in FIG. 14, the first sheet S is fed from the manual feeding roller 123, and first, the leading edge of the sheet S is detected by the registration sensor 106 (step S1) and then the control section 129 is operated. If the discharge sensor 119 does not detect the leading edge of the sheet S and the registration sensor 106 detects the sheet S even after the predetermined time T ₁ has elapsed by starting the timer provided in step S2. In step S3, the user is notified of the occurrence of the jam by activating the jam notification unit 132 by recognizing that the jam is the discharge delay jam of the sheet S (step S3).

It should be noted that, at the time T ₁ , the registration sensor 106
A time obtained by dividing the distance of the conveyance path from the sheet ejection sensor 119 by the conveyance speed of the sheet S and a margin is set.

On the other hand, when the registration sensor 106 detects the absence of the sheet and the trailing edge of the sheet S is detected before the leading edge of the sheet S reaches the discharge sensor 119, the length S of the sheet S is short. The control unit 129 recognizes that the sheet is a sheet (step S4), and the control unit 129 sets the time T ₂ until the jam detection unit detects the discharge delay jam as T ₂ = T ₁ + T
Set to α (step S5).

The time Tα is set to a margin corresponding to the slip time of the sheet S conveyed by the conveyor belt 120.

When it is recognized in step S4 that the short size sheet S is being conveyed, until the discharge sensor 119 detects the leading edge of the sheet S,
The control unit 129 stops the manual feeding roller 123 and does not feed the succeeding sheet S. As a result, the print timing of the succeeding sheet S can be changed as appropriate according to the transport state of the preceding sheet S, and thus optimum throughput can be obtained.

If the discharge sensor 119 does not detect the leading edge of the sheet S and the time T ₂ elapses, the jam detecting means recognizes that a discharge delay jam has occurred in the short sheet S (step S6). The jam notification means 132 is operated to notify the user of the occurrence of a jam.

If the discharge sensor 119 detects the leading edge of the sheet S before the time T ₂ elapses and the jam does not occur, the registration sensor 106 detects the leading edge of the sheet S for a predetermined time. The succeeding sheet S is fed after T ₃ (step S8).

On the other hand, if the discharge sensor 119 reaches the leading edge of the sheet S before the registration sensor 106 detects the absence of the sheet, the sheet is recognized as a long (normal) sheet (step S7), and the jam is left as it is. If it does not occur, the succeeding sheet S is fed after a predetermined time T ₃ from the detection of the leading edge of the sheet S by the registration sensor 106 (step S8).

In the above embodiment, the registration sensor determines whether or not the sheet S is shorter than the conveyance path length L101.
Although the determination is made based on the detection information of 106 and the discharge sensor 119, as another configuration, it is determined whether or not the sheet S is short by detecting the time when the leading edge and the trailing edge of the sheet S pass the registration sensor 106. It may be configured to perform.

Next, the case where the sheet S is fed from the sheet cassette 101 by the pickup roller 102 will be described with reference to FIG. When the sheet S is fed from the sheet cassette 101, the size code of the sheet S is determined by the sheet size sensor 128 provided in the sheet cassette 101, and the size code information is obtained by the control unit 12 of the apparatus main body C101.
9 so that the size of the sheet S can be recognized when the sheet S of a predetermined size is accommodated in the sheet cassette 101 and then the sheet cassette 101 is attached to the apparatus main body C101. Has become.

When the sheet S is fed from the sheet cassette 101, the pre-feed sensor 105 detects the leading edge of the sheet S before the sheet S reaches the registration roller pair 104, and then the intermediate roller pair 103, which serves as a sheet standby unit, operates. By the operation, the sheet S can be made to stand by at a predetermined position.

In the configuration as described above, first, in step S1 of FIG. 15, the length of the sheet S is determined by the detection information from the sheet size sensor 128 so that the length of the sheet S is nip portion A of the transfer portion.
When the conveyance path distance L101 between 101 and the nip portion B101 of the fixing unit is shorter, the leading edge of the first sheet S is detected by the registration sensor 106 (step S2) and then the timer 1 is started (step S2). S3), starts feeding the second sheet S after a predetermined time T ₄ (step S
4) If the image development of the print controller is completed, the image is recorded on the first sheet S as it is (step S5).

Then, the second sheet S is pre-fed
After being detected by the sensor 105 (step S6), the
The mar 2 is started (step S7). As mentioned above
In addition, the leading edge of the first sheet S is detected by the registration sensor 106.
Is detected for a predetermined time T _FourLater on the second sheet S
Feeding starts (step S4), but the first sheet S
If the tip of the is not yet detected by the emission sensor 119
If the print controller image development is complete,
Also, the tip of the second sheet S becomes the pre-feed sensor 105.
A predetermined time T after being detected_FiveMedium when
The inter-roller pair 103 is stopped (step S8).
And wait for the second sheet S at the position of the intermediate roller pair 103.
Let it.

This stop position is the same as the standby position when the image development of the print controller is not completed. If the discharge sensor 119 cannot detect the leading edge of the sheet S even after a lapse of a predetermined time T ₂ after the leading edge of the first sheet S is detected by the registration sensor 106, the jam detecting unit detects one sheet. Recognizing that a discharge delay jam has occurred on the eye sheet S (step S9), the recording operation is stopped, and the jam notification means
132 is activated to notify the user of the occurrence of a jam.

The predetermined time T ₂ is set by {the time required to carry from the registration sensor 106 to the discharge sensor 119 in the normal carrying + the margin + the margin of the slip time in the carrying by the carrying belt 120}, as described above. This value is set to be larger than the time T ₁ until the discharge delay jam of the sheet S is detected in the normal size described above.

If the discharge sensor 119 detects the leading edge of the sheet S before a predetermined time T ₂ has elapsed since the leading edge of the first sheet S was detected by the registration sensor 106, then that point in time. If the image development of the print controller is completed at, the intermediate roller pair 103 is rotationally driven to convey the second sheet S (step S10), 2
Image recording is performed on the first sheet S (step S11).

If the length of the sheet S is longer than the conveyance path length L101 in step S1, the leading edge of the first sheet S is detected by the registration sensor 106 (step S12) and then the timer 1 is started. is started (step S13), and starts feeding the second sheet S after a predetermined time T ₄ (step S14), and if the image development of the print controller has been completed, it is the first sheet S
The image is recorded on the sheet (step S15), and if the image development of the print controller is continuously completed, the image is recorded on the second sheet S as it is (step S16).

In the above-described embodiment, the size of the sheets S accommodated in the sheet cassette 101 has been described as being recognized in advance by the apparatus body C101 when the sheet cassette 101 is attached to the apparatus body C101. As another configuration, when a sheet S having an irregular size can be accommodated in the sheet cassette 101 like a universal cassette, the size of the sheet S cannot be recognized by the apparatus main body C101, but in such a case, Pre-feed sensor 10
Alternatively, the control similar to that described above can be performed by configuring the registration sensor 106 to determine whether the sheet S is short by detecting the passage time of the sheet S.

Further, in the above-described embodiment, the conveyance control of the conveyor belt 120 provided between the nip portion A101 of the transfer portion and the nip portion B101 of the fixing portion has been described. Part A101
It is not limited to the conveying path from the sheet to the nip portion B101 of the fixing unit, but if the sheet S is long, it is always pinched, and if it is short, it is
When the sheet S is conveyed without being pinched, the length of the sheet S is detected and the jam detection time setting is changed according to the length of the sheet S, or the conveyance timing of the subsequent sheet S is changed. As long as it is configured, the control position in the sheet conveying means and the sheet conveying path can be changed appropriately.

[Seventh Embodiment] Next, a seventh embodiment having another configuration will be described with reference to FIGS. 16 to 22. FIG. 16 is a sectional explanatory view illustrating an image forming apparatus according to the seventh embodiment, and FIG.
Is a perspective view showing the configuration of the sheet skew correcting device of the seventh embodiment, FIG. 18 is a plan view showing the configuration of the sheet skew correcting device of the seventh embodiment, and FIGS. 19 to 21 are the sheets of the seventh embodiment. FIG. 22 is an explanatory plan view of the operation of the skew feeding correction device, and FIG. 22 is a plan view showing how the skew feeding correction device of the seventh embodiment corresponds to different sheet widths.

First, the overall structure of the image forming apparatus of the seventh embodiment will be described with reference to FIG. Sheets S made of paper, synthetic resin or the like contained in the feeding unit U are fed out by the feeding roller 201 and separated and fed one by one by a separating means (not shown).

Sheet S fed by feeding roller 201
Is conveyed by a pair of conveying rollers 205 serving as a sheet conveying means, and is further arranged on the downstream side in the sheet conveying direction (hereinafter, simply referred to as “downstream side”) as a conveying roller pair 213 serving as a sheet conveying rotating body serving as a sheet conveying means. , 214, which is a process cartridge 207 that serves as an image forming unit.
And a photoconductor drum 208 as an image-bearing rotator composed of an electrophotographic photoconductor is guided to the opposing image forming unit.

On the other hand, the control unit 204 is attached to the photosensitive drum 208 whose surface is uniformly charged by the charger.
The laser scanner 206 controlled by scans the laser beam according to the image information to form a latent image. Then, a toner image is formed on the latent image by the developing device provided in the process cartridge 207.

Then, the sheet S is conveyed between the photoconductor drum 208 and the transfer charger 212 in synchronization with the rotation of the photoconductor drum 208, and is transferred by the transfer charger 212.
The toner image formed on the sheet S is transferred to the sheet S. The sheet S on which the image is transferred is conveyed to the fixing unit 211,
After the toner image is fixed on the sheet S by being heated and pressed by the fixing unit 211, the pair of discharge rollers 202, 20
It is discharged to the outside by 3

Further, the conveying roller pair 205 and the conveying roller pair 21
3 and 214, and downstream in the vicinity of the pair of transport rollers 213 and 214, and upstream of the photosensitive drum 208 in the sheet transport direction (hereinafter, simply referred to as “upstream side”). Sensors 209 and 210 are arranged, and the pair of conveying rollers 213 and 214 are described in detail in FIGS.
The sheet skew correction device shown in FIG.

The sensor 210, as shown in FIGS.
The sensor flag 210a, which is arranged on the downstream side in the vicinity of the conveying roller pair 213, 214 and is rotatable around the shaft 210b when the sheet S does not pass, has one end of the conveying roller pair 213, 21.
The first state in which the other end of the sensor flag 210a is arranged so as to block the optical path of the detection unit 210c formed of a photo sensor, and is arranged so as to project into the sheet conveyance path 221b provided on the downstream side of 4 ( (See FIGS. 19 and 20), and the sheet S is engaged with one end of the sensor flag 210a protruding to the sheet conveying path 221b, and the sensor flag 210a is moved around the shaft 210b to form an arrow a201 in FIG.
Direction of the sensor flag 210a, the other end of the sensor flag 210a
It is configured to be rotatable in a second state (see FIG. 21) arranged at a position where the optical path of 210c is transmitted.

Next, the configuration of the sheet skew feeding correction device will be described with reference to FIG.
This will be described with reference to FIG. A pair of conveying rollers 213 whose rotation axis is arranged in parallel with the rotation axis direction of the photosensitive drum 208.
, 214 are divided and arranged in a direction orthogonal to the sheet conveying direction as shown in FIG.
A conveying roller 214 fixed to the rotating shaft 214a and rotating integrally with the rotating shaft 214a, and a main body frame (not shown) arranged at a position corresponding to each of the plural divided conveying rollers 214 so as to face each other. And a transport roller 213 which is a sheet transport rotator and is fixed to a rotary shaft 218 which is rotatably supported.

On the rotary shaft 218 to which the transport roller 213 is fixed,
A plurality of auxiliary rollers 219 having an outer diameter smaller than that of the conveying rollers 213 are rotatably fitted to the rotating shaft 218 between a plurality of conveying rollers 213 arranged in the direction of the rotating shaft 218. On the outer peripheral surface of the auxiliary roller 219, a plurality of shutter members 215 integrally connected by a connecting member 216 are rotatably fitted to the auxiliary roller 219.

As shown in FIG. 18, the sheet S is conveyed with reference to the center, and the shutter member control surface 21 of the auxiliary rollers 219 arranged on both sides of the conveying roller 213 arranged in the central portion C201.
The shutter member 215 is positioned by the auxiliary roller 219 with respect to the conveyance roller 213 by the contact and sliding of the contact surface 15h of the shutter member 215 fitted to the auxiliary roller 219. .

With the above-mentioned structure, the shutter member 215 and the transport roller 213 in the direction of the rotation axis 218 are the auxiliary rollers.
Since the two are not separated by 219 and do not come into contact with each other, the transport roller 213 and the shutter member 215 can rotate independently of each other. Therefore, the transport roller 213
Contacting the shutter member 215,
It does not hinder the rotation operation of.

Although the auxiliary roller 219 is used in this embodiment, the position of the shutter member 215 in the direction of the rotation axis 218 may be restricted by, for example, an E-shaped retaining ring (so-called E ring). But good.

The plurality of shutter members 215 abut against the leading edge of the sheet S conveyed by the pair of conveying rollers 205.
Rotation between a first posture (see FIGS. 19 and 20) in which 0a abuts and the leading end of the sheet S can be locked and a second posture in which the sheet S can pass (see FIG. 21). The shutter member 215 is configured to be swingable about the shaft 218, and the shutter members 215 are connected by a connecting member 216 in phase with each other about the rotational movement about the rotation shaft 218.

When the sheet S is not engaged, the shutter member 215 is acted upon by the gravity balance of the shutter member 215 and the connecting member 216 about the rotation shaft 218 as the center of rotation.
It is always held in the first posture state shown in FIG.

That is, in this embodiment, the shutter member 21
As the urging means for urging the connecting member 216 to the first posture state, the gravitational balance acting on the own weight of the connecting member 216 connecting the shutter member 215 is the rotation center of the rotating member 21 of the connecting member 216.
It uses the rotational moment generated for 8.

The shutter member 215 includes a carrying roller.
An abutting surface 220a is provided in the nip portion between the transport roller 213 and the transport roller 213, which serves as a sheet leading end contacting surface that is capable of contacting the leading end of the sheet S and locking the sheet S immediately before the sheet S enters. Then, the butting surface 22 of the shutter member 215
0a indicates that when the shutter member 215 is in the first posture state,
It is arranged on the upstream side of the nip portion between the transport roller 214 and the transport roller 213.

In this embodiment, the plurality of shutter members 215 are connected by the connecting member 216, but as another configuration, the shutter member 215 and the connecting member 216 are connected.
And may be integrally formed.

Here, when the sheet S is conveyed by the pair of conveying rollers 205 and, for example, the sheet S obliquely enters the pair of conveying rollers 213 and 214 as shown in FIG. If the member 216 is not present, the sheet S is conveyed in a skewed posture and reaches the image forming portion, and the image transferred to the sheet S is recorded while being inclined with respect to the sheet S.

However, in the present embodiment, the shutter member 215 and the connecting member 216 are configured as described above and provided on the conveying roller pairs 213 and 214, so that the skew feeding of the sheet S is corrected by the operation described later. It

First, the leading end of the leading side of the sheet S (lower side in FIG. 18) comes into contact with the abutting surface 220a of the shutter member 215 arranged at the position corresponding to the leading end. At this point, the leading edge of the sheet S cannot push and rotate the shutter member 215 against the gravity acting on the own weight of the connecting member 216.

Then, the conveying roller pair 205 further causes the sheet S
When the sheet is conveyed, the leading end of the sheet S is locked in contact with the abutting surface 220a of the shutter member 215, and the leading end of the succeeding side of the sheet S is positioned at a position corresponding to the leading end. Abutting surface 22 of the shutter member 215 arranged
When the sheet S is further conveyed by the conveying roller pair 205, the sheet S forms a curved loop as shown in FIG. 20, and the waist strength of the sheet S itself is increased. As a result, the skew of the sheet S is corrected and the conveyance roller pair 21
The leading edge of the sheet S becomes parallel to the direction of the rotational axis of 3,214.

Then, as shown in FIG. 20, when the sheet S forms a predetermined loop in the sheet conveying path 221a provided on the upstream side in the vicinity of the conveying roller pair 213, 214, the shutter member 215 is rotated about the rotation axis. Focusing on 218, arrow b20 in FIG.
The force of rotating in one direction and retracting is generated by the waist strength of the sheet S, and as shown in FIG.
When the sheet is retracted, the leading edge of the sheet S is the shutter member 21.
The seat S is released from the engagement by the abutting surface 220a of the sheet 5.
The leading end of the sheet enters the nip portion between the transport roller 214 and the transport roller 213, and is nipped and transported by the nip portion of the transport roller pair 213, 214 by the feeding operation of the transport roller pair 213, 214.

Then, the sheet S has a pair of conveying rollers 213,
The sensor flag 210a of the sensor 210 disposed on the downstream side in the vicinity of 214 is engaged and the sensor flag 210a is rotated around the shaft 210b in the direction of arrow a201 in FIG. By doing so, the sensor 210 detects the passage of the sheet S.

When the sensor 210 detects the sheet S,
The laser scanner 206 forms a latent image on the surface of the photoconductor drum 208 and a series of process operations of the process cartridge 207 forms a toner image on the surface of the photoconductor drum 208, which is synchronized with the rotating operation of the photoconductor drum 208. The toner image formed on the surface of the photosensitive drum 208 is transferred onto the conveyed sheet S.

As described above, the sensor flag 210a is
The image forming operation of the image forming unit is started according to the detection information of the detection unit 210c by operating 210c, so that an image is formed regardless of the time required for the sheet S to pass through the shutter member 215. The timing can be kept constant. That is, the timing for forming an image can be maintained constant even when the time for passing through the shutter member 215 differs for various sheets S having different waist strengths.

At this time, since the leading edge of the sheet S is parallel to the rotation axis direction of the pair of conveying rollers 213, 214 by the above-described skew feeding correction operation, the pair of conveying rollers 213, 214 is provided.
Thus, if a sufficient conveying force acts on the sheet S,
The sheet S can be conveyed without skew to the photoconductor drum 208, and the image transferred onto the sheet S is
You can record without tilting.

Here, as shown in FIG. 22, the length of the used sheet S in the direction orthogonal to the sheet conveying direction (hereinafter,
When the “width of the sheet S”) is relatively large (the sheet S shown by the solid line in FIG. 22), the two shutter members 215a, 21 arranged mainly in the vicinity of both side end portions of the sheet S are arranged.
As described above, 5d acts on the leading edge of the sheet S to correct the skew of the sheet S.

When the width of the sheet S to be used is relatively small so as not to cover the shutter members 215a and 215d (the sheet S indicated by the chain double-dashed line in FIG. 22), the central portion of the sheet S is smaller than that of the shutter members 215a and 215d. The skew feeding of the sheet S is corrected by the shutter members 215b and 215c arranged at.

Here, in order to obtain the skew feeding correction capability of the sheet S with higher accuracy, it is preferable that the plurality of shutter members 215 corresponding to the width of the sheet S be opened as much as possible.
The sheet S with respect to the rotation axis direction of the pair of conveying rollers 213 and 214
Because the correction angle error at the tip of the
It is preferable to dispose 215 near both side ends of the conveyed sheet S, but a shutter member 215 is also arranged near the conveyance central portion C201 of the sheet S so that skew feeding can be corrected even for a sheet S having a relatively small width. Consists of multiple shutter members
It is good to have 215.

At this time, the central portion C201 of the sheet S conveyance path
It is preferable that the distance between the two shutter members 215b and 215c on both sides closest to the sheet is smaller than the minimum width of the sheet S used in the image forming apparatus.

Also, the abutting surface 22 of the shutter member 215
The distance between 0a and the nip portion between the transport roller 214 and the transport roller 213 is configured to be as small as possible as in the present embodiment, and the leading edge of the sheet S has the transport roller 214 and the transport roller 213.
The shutter member 215 is configured so as to correct the skew of the sheet S by entering the nip portion of the sheet S and the front end of the sheet S by the abutment surface 220a and locking the sheet S immediately before being sandwiched by the nip portion. Thus, the skew feeding correction of the sheet S is performed, and immediately thereafter, the sheet S is nipped and transported in the nip portion between the transport roller 214 and the transport roller 213, so that the skew feeding correction effect of the sheet S can be maintained.

Further, since the urging means for urging the shutter member 215 to the first posture state is constituted by using the gravity balance acting on the own weight of the connecting member 216, the constitution is simple and the seat is The shutter member 215 is rotated by being pressed by S, and the sheet S is moved by the shutter member 215.
Shutter member 215 for the sheet S when passing through
This is advantageous because the biasing resistance from does not increase.

In this case, in particular, the reaction force received by the sheet S from the shutter member 215 when the sheet S pushes the shutter member 215 and swings the shutter member 215, and the leading end of the sheet S is the shutter member 215. Since the gravity balance acts so that the sheet S becomes weaker than the reaction force received from the shutter member 215 when it comes into contact with 215 for the first time, the sheet S rotates the shutter member 215 and easily retracts and passes through. This is preferable because it does not cause jamming.

Further, by changing the weight of the connecting member 216 in correspondence with the waist strength of the various sheets S, it is possible to cope with the skew correction of the sheets S having various waist strengths.

In this embodiment, the shutter member 215
Although the connecting member 216 and the connecting member 216 are configured to rotate about the rotation shaft 218 of the transport roller 213, as another configuration, the configuration is configured to rotate about the rotation shaft 214a of the transport roller 214. But good.

[Eighth Embodiment] Next, an eighth embodiment having another structure will be described with reference to FIGS. 23 (a) and 23 (b).
FIG. 23A is a horizontal cross-sectional explanatory view showing the outer shape of the abutting surface of the shutter member of the seventh embodiment, and FIG.
It is a horizontal cross-section explanatory drawing which shows the external shape of the abutting surface of the shutter member of embodiment. The same components as those in the seventh embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the seventh embodiment, as shown in FIG. 23 (a), since the abutting surface 220a of the shutter member 215 is formed as a flat surface, the end of the abutting surface 220a becomes a corner, and this When the tip of the sheet S comes into contact with the corner, the tip of the sheet S may be damaged.

In order to prevent this, in this embodiment,
As shown in FIG. 23 (b), the abutting surface 220b of the shutter member 215 is composed of an arc surface having a predetermined diameter or a curved surface having R surfaces at the corners, and the sheet S is conveyed obliquely. When the leading end of the sheet S comes into contact with the abutting surface 220b of the shutter member 215, it does not come into contact with the corners as in the fifth embodiment, and the leading end of the sheet S is not damaged.

At this time, the R surface or the arc surface of the abutting surface 220b is formed such that the tip of the sheet S is located at both side ends of the abutting surface 220b during the maximum skew of the sheet S assumed by the sheet skew correcting apparatus. By setting the predetermined curvature so as not to hit the changing portion of the curvature of the boundary with the R surface or the arc surface, it is possible to achieve both the skew feeding correction capability of the sheet and the damage prevention effect of the sheet S in an optimum state. . Other configurations are similar to those of the seventh embodiment, and similar effects can be obtained.

[Ninth Embodiment] Next, a ninth embodiment having another structure will be described with reference to FIG. FIG. 24 is a vertical cross-sectional explanatory view showing the outer shape of the abutting surface of the shutter member of the ninth embodiment. The same components as those in the seventh embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the seventh embodiment, as shown in FIG. 20, when the shutter member 215 is in the first posture position, the abutting surface 220a of the shutter member 215 is against the sheet surface of the conveyed sheet S. And the abutting surface 220a intersects the sheet surface of the abutting sheet S at approximately 90 °. In this case, depending on the formation state of the loop of the sheet S, the leading end of the sheet S may be abutting surface.
There is a possibility to escape from 220a to the lower part of FIG.

In order to prevent this, in this embodiment,
As shown in FIG. 24, when the shutter member 215 is in the first posture position, the abutting surface 220c of the shutter member 215 is
The sheet S is formed in an acute angle direction of 90 ° or less in the clockwise direction in FIG. 24 with respect to the sheet surface of the conveyed sheet S, and the abutting surface 220c is formed on the sheet surface of the abutting sheet S. On the other hand, they intersect at an acute angle of 90 ° or less.

As a result, the leading edge of the sheet S falls into the groove 220d formed by the abutting surface 220c and the end surface 215e of the shutter member 215, and the leading edge of the sheet S may escape from the abutting surface 220c as described above. Instead, the skew feeding correction operation of the sheet S can be surely performed by locking the leading end of the sheet S. Other configurations are similar to those of the seventh embodiment, and similar effects can be obtained.

[Tenth Embodiment] Next, the first embodiment of another configuration will be described.
The 0th embodiment will be described with reference to FIGS. FIG.
Is a plan view showing the configuration of the skewed sheet correcting device of the tenth embodiment, FIG. 26 is a sectional explanatory diagram showing the configuration of the skewed sheet correcting device of the tenth embodiment, and FIG. 27 is a perspective view of A201 portion in FIG. 25. FIG. 6 is an enlarged view showing a main part of a reaction force switching means of a biasing means. The same components as those in the seventh embodiment are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 25, in this embodiment, the shutter member 215 is biased to the first posture state with respect to the skewed sheet correcting device configured similarly to the seventh embodiment. A torsion coil spring 224 serving as a biasing means is additionally provided.

The torsion coil spring 224 is slidably fitted to the rotating shaft 218, the end 224b on the side of the connecting member 216 is locked to the connecting member 216, and the end 224a on the side of the frame 217 is installed in the device. The first and second projections 223a and 223b, which are reaction force switching means provided on the main body frame 217, are appropriately and selectively locked.

For example, a sheet S having normal waist strength
In this case, the end 224a of the torsion coil spring 224 on the frame 217 side is locked to the first protrusion 223a. With the above structure, the shutter member 215 is a torsion coil spring.
It is always urged by 224 in the direction of arrow c202 in FIG.

In the above structure, the torsion coil spring is used.
It is possible to increase the urging force F201 acting in the direction of arrow c202 in FIG. 26 by replacing the end portion 224a of the frame 217 on the side of the frame 217 with the second protrusion 223b. Torsion coil spring 224 according to strength
The end 224a on the frame 217 side of the first and second projections 223
A proper biasing force F201 can be obtained by selectively locking a and 223b.

With the above configuration, the sheet S is conveyed with the skew feeding corrected by the shutter member 215 in substantially the same manner as in the seventh embodiment, so a detailed description thereof will be omitted here.

Here, as the sheet S, various kinds of sheets S are used, for example, from thin paper having a weight of about 50 g per square meter to thick paper having a weight of about 120 g per square meter.

For example, when the sheet S is thin paper, the sheet S
Even if the biasing force F201 of the shutter member 215 is small, the sheet S easily forms a loop and skew of the sheet S is easily corrected.

On the other hand, when the biasing force F201 by the torsion coil spring 224 is set larger than necessary because the sheet S has a weak stiffness, the sheet S rotates the shutter member 215 in the direction opposite to the arrow c202 direction in FIG. As a result, it becomes difficult to retract the shutter member 215 and pass through the shutter member 215, causing a problem such as a jam of the sheet S.

When the sheet S is a thick sheet, the sheet S is stiff, so that when the biasing force F201 of the shutter member 215 is small, it is difficult for the sheet S to form a loop and the sheet S
There is a problem that the shutter member 215 is rotated and retracted and the shutter member 215 is passed without being completely corrected.

Here, in this embodiment, the end portion 224a of the torsion coil spring 224 on the frame 217 side is the first protrusion portion.
Of the seats S used when locked to 223a,
Even if the sheet S is the weakest, it is assumed that the sheet S is rotated to retract the shutter member 215 so that the biasing force F201 can pass through the shutter member 215. When the sheet S having a strong stiffness is conveyed, the skew correction amount of the sheet S becomes smaller than that of thin paper.

At this time, the frame of the torsion coil spring 224
Replacing the end 224a on the 217 side with the second protrusion 223b,
The biasing force F201 is increased, and a large skew feed correction amount can be secured even on thick paper.

By configuring as in the above-described present embodiment, it is possible to secure transport performance when the sheet S is thin paper or the like and is relatively weak, and is large when the sheet S is thick or the like and relatively strong. The skew correction capability can be exhibited.

In the present embodiment, the torsion coil spring 22
By changing the position at which the end 224a of the frame 217 on the side of the frame 217 is locked, the urging force F20 by the torsion coil spring 224 is changed.
1 has been adjusted, but the present invention is not limited to these, and the urging force F for urging the shutter member 215 to the first posture state.
201 can be constructed using various other means capable of adjusting.

[Eleventh Embodiment] Next, the first embodiment of another configuration will be described.
One embodiment will be described with reference to FIGS. 28 and 29. Figure 28
FIG. 29A is a plan view showing the configuration of the sheet skew feeding correction device of the eleventh embodiment, and FIGS. 29A and 29B are cross-sectional explanatory views showing the configuration of the sheet skew feeding correction device of the eleventh embodiment. The same components as those in the seventh embodiment are designated by the same reference numerals and the description thereof will be omitted.

As shown in FIG. 28, in the present embodiment, a sensor flag 216a for operating a detection unit 210c serving as a sheet detection unit is integrally provided in a sheet skew correcting device configured similarly to the seventh embodiment. It is provided and configured.

A sensor flag 216a fitted to the rotary shaft 218, rotatably supported on the rotary shaft 218, and fixed to the connecting member 216 is provided at one end of the rotary shaft 218. The sensor flag 216a is rotatable around the rotary shaft 218 integrally with the connecting member 216. When the shutter member 215 rotates, the sensor flag 216a rotates integrally with the shutter member 215. Move.

At a position facing the sensor flag 216a, a detecting portion 210c which constitutes a sheet detecting means is arranged as in the seventh embodiment, and as shown in FIG. 29 (a), a shutter member 215 is provided. The sensor flag 216a is set to a position that allows the optical path of the detection unit 210c to pass therethrough when in the first posture position where it can come into contact with the leading edge of the sheet S and lock the leading edge of the sheet S.

Further, as shown in FIG. 29 (b), when the shutter member 215 is in the second posture position where the sheet S can pass, the sensor flag 216a is set to the position where the optical path of the detecting portion 210c is blocked. ing.

In the above structure, as in the seventh embodiment, the leading edge of the sheet S conveyed by the conveying roller pair 205 abuts against the abutting surface 220a of the shutter member 215 and is locked to form a loop. After the skew is corrected, the shutter member 215 is pushed up, rotated, and retracted, and passes through the shutter member 215. At this time, the sensor flag 216a rotates about the rotary shaft 218 by the same angle as the shutter member 215 in the direction of arrow b201 in FIG. 29 (a), and interrupts the optical path of the detection unit 210c.

Therefore, the laser scanner 206 forms a latent image on the surface of the photoconductor drum 208 based on the detection information of the detection unit 210c, and a toner image is formed on the surface of the photoconductor drum 208 by a series of process operations of the process cartridge 207. Then, the toner image formed on the surface of the photoconductor drum 208 is transferred to the sheet S conveyed in synchronization with the rotation operation of the photoconductor drum 208.

In this embodiment, a plurality of shutter members 215 are connected by the connecting member 216, and the sensor flag 216a is fixed to the connecting member 216. However, as another configuration, the shutter member 215 and the connecting member 216 are provided. The sensor flag 216a may be integrally formed.

In the above embodiment, the sensor flag 216a is provided on the connecting member 216 connecting the shutter member 215, and the sensor flag 216a interlocked with the rotating operation of the shutter member 215.
Is configured to activate the detection unit 210c, and the image forming operation of the image forming unit is started based on the detection information of the detection unit 210c, so that the sheet S operates the shutter member 215 similarly to the seventh embodiment. Regardless of the time required to pass the image, the timing of forming an image can be maintained constant, and a part of the shutter member 215 also serves as a part of the sheet detecting means. It is possible to reduce the cost of the device.

[Twelfth Embodiment] Next, a first embodiment of another configuration will be described.
The second embodiment will be described with reference to FIGS. 30 and 31. Fig. 30
Is a cross-sectional explanatory view showing the structure of the image forming apparatus of the twelfth embodiment, and FIG. 31 is a view of the A202 portion in FIG. The same components as those in the seventh embodiment are designated by the same reference numerals and the description thereof will be omitted.

In this embodiment, the skewed sheet correcting device is integrally formed with the process cartridge 207, and the shutter member 215 is provided around the rotation axis of the photosensitive drum 208, which is the image bearing rotating body serving as the sheet conveying means. It is configured to be rotatable. In FIG. 31, a plurality of shutter members 215 having an abutting surface 220a are integrally connected by a connecting member 216, and the connecting member 216 is connected to the dowels 208a and 208b provided at both ends of the photosensitive drum 208. Dowel 208a, 20
It is rotatably supported around 8b.

As shown by the solid line in FIG. 30, when the shutter member 215 is in the first posture position where it can abut the leading edge of the sheet S and lock the leading edge of the sheet S, the shutter member 215
The abutting surface 220a of the photosensitive drum 208 and the transfer charger 21
It is arranged on the upstream side near the nip portion with 2. The state position where the shutter member 215 is shown by the broken line in FIG. 30 is the second posture position where the sheet S can pass.
Other configurations are similar to those of the seventh embodiment, and similar effects can be obtained.

With the above-described structure, similarly to the seventh embodiment, after the skew correction is performed by the shutter member 215 arranged on the pair of conveying rollers 213 and 214, the pair of conveying rollers 213 that act as the sheet conveying means this time. , 214, the sheet S is conveyed, and when the leading end of the sheet S comes into contact with the abutting surface 220a of the shutter member 215 in the first posture position shown by the solid line in FIG. 30, as in the seventh embodiment, Sheet S
Forms a loop, and the skew of the sheet S is corrected by the waist strength of the sheet S, and then the shutter member 215 is pressed to remove the dowel.
When the sheet S is rotated in the clockwise direction in FIG. 30 about the 208a and 208b to the second posture position shown by the broken line in FIG. 30, the sheet S passes through the shutter member 215 and is conveyed to the downstream side. .

According to the above arrangement, the process cartridge
Dowels 208a, 208b of the photoconductor drum 208 provided in 207
Since the shutter member 215 is rotatably attached to the photoconductor drum 208 via the connecting member 216, the alignment (positional accuracy) of the shutter member 215 with respect to the photosensitive drum 208 is accurately maintained. That is, the alignment of the sheet S with respect to the photosensitive drum 208 can be accurately maintained,
The image recording accuracy can be further improved.

In this embodiment, the shutter member 215
To the dowel 208 of the photoconductor drum 208.
Although it is configured to be rotatable about a and 208b as a center, as another configuration, when the transfer charger 212 is composed of a transfer rotating body, the shutter member 215 is rotated around the center of rotation of the transfer rotating body. The same effect can be obtained even if it is movably provided.

[Thirteenth Embodiment] Next, a first embodiment of another configuration will be described.
A third embodiment will be described with reference to FIG. Figure 32 shows the first
FIG. 3 is a cross-sectional explanatory diagram showing a configuration of an image forming apparatus of a third embodiment. The same components as those in the seventh embodiment are designated by the same reference numerals and the description thereof will be omitted.

In this embodiment, a plurality of sheet skew correcting devices having the same structure as in the seventh embodiment are arranged on the conveying path for conveying the sheet S. In FIG. 32, in the image forming apparatus according to the present embodiment, the feeding units U201 and U202 are configured in upper and lower two stages. And
Similar to the seventh embodiment, the process cartridge 207
On the upstream side in the vicinity of the sheet conveyance roller pair 213A, 214A equipped with a shutter member 215A, which is a sheet skew correction device, and the like.
Is arranged.

Further, the feeding units U201, U of the apparatus main body
A conveyance roller pair 213 B, 214 equipped with a shutter member 215 B, which is a sheet skew correction device, similarly configured in the same manner as in the seventh embodiment on the downstream side in the vicinity of the confluence B201 of the sheet conveyance path from 202. B is arranged.

Further, in the lower feeding unit U202 in which the conveyance path length of the sheet S to the image forming portion where the photoconductor drum 208 arranged in the process cartridge 207 faces is relatively long, the lower feeding unit U202 is different from that in the seventh embodiment. A pair of transport rollers 213 C and 214 C equipped with a shutter member 215 C, which is a sheet skew correcting device having the same configuration, is arranged.

Further, on the downstream side in the vicinity of each of the conveying roller pairs 213 A and 214 A and the conveying roller pairs 213 B and 214 B,
A sensor that serves as a sheet detection unit as in the seventh embodiment.
209 and 210 are arranged. Other configurations are similar to those of the seventh embodiment, and similar effects can be obtained.

With the above structure, the sheet S fed by the feeding roller 201a from the feeding unit U202 is
A loop is formed between the feeding roller 201a and the conveying roller pair 213C and 214C to correct skew, and then the sheet is conveyed to the downstream side, and this time, the conveying roller pair 213C and 214C and the conveying roller. After forming a loop between the pair 213 B and 214 B to correct the skew again, the sheet is conveyed to the downstream side, and further this time, the conveying roller pair 213 B and 214 B and the conveying roller pair 213 A and 214 A.
After forming a loop between and, the skew is corrected again,
Photoconductor drum 20 placed in process cartridge 207
8 is conveyed to the opposite image forming unit.

Further, from the feeding unit U201 to the feeding roller
The sheet S delivered by 201b first forms a loop between the feeding roller 201b and the pair of conveying rollers 213B and 214B to correct skew, and is then conveyed to the downstream side. This time, the transport roller pair 213B, 214B and the transport roller pair
After forming a loop between 213A and 214A and correcting the skew again, the photosensitive drum 208 disposed in the process cartridge 207 is conveyed to the opposing image forming unit.

With these configurations, even when the length of the conveyance path of the sheet S from the feeding unit U accommodating the sheet S to the process cartridge 207 serving as the image forming means is relatively long, the above-mentioned parts are provided at various places. By arranging a plurality of sheet skew correcting devices, skew correction of the sheet S can be performed on the transport path of the sheet S at any time, and the sheet S being transported is skewed due to transport resistance or the like on the sheet transport path. Even in the case of performing the skew feeding, the skew feeding correction can be performed at a predetermined position at any time before the skew feeding accumulates and becomes large, so that the image recording accuracy can be further improved.

In the above embodiment, an example in which the sheet skew feeding correction devices are arranged at three positions is shown. However, as another configuration, a desired number of sheet skew feeding correction devices may be provided at other desired positions. It may be configured by appropriately arranging.

[Fourteenth Embodiment] Next, a first embodiment of another configuration will be described.
An image forming apparatus according to the fourth embodiment will be described with reference to FIG. FIG. 33 is an explanatory sectional view showing the structure of the image forming apparatus of the fourteenth embodiment. The same components as those in the seventh embodiment are designated by the same reference numerals and the description thereof will be omitted.

In each of the above-described embodiments, the sheet S needs to form a loop of an amount necessary for skew correction of the sheet S in a state where the leading end of the sheet S is in contact with and locked by the shutter member 215. is there. The loop amount and the skew feed correction amount of the sheet S have substantially the same value relationship, and when the skew feed amount of the sheet S is large, it is necessary to secure a stable predetermined loop amount.

In FIG. 33, the leading edge of the sheet S conveyed by the conveying roller pair 205 serving as the sheet conveying means is abutted against the abutting surface 220a of the shutter member 215 provided on the conveying roller pair 213, 214 serving as the sheet conveying means. When the sheets S are brought into contact with each other and locked, the sheet S is conveyed to the conveying roller pair 205 and the conveying roller pair 213.
, 214 to form a loop having a predetermined curvature so as to be separated from the conveyance guide surface G201 serving as a sheet guide.

When a predetermined loop amount is formed and there is no member for guiding the sheet S on the side facing the conveyance guide surface G201, the sheet S endlessly increases the loop amount and buckles, There is a problem that the sheet S is jammed because it cannot enter the nip portion of the pair of transport rollers 213 and 214 due to the urging force of the shutter member 215.

The present embodiment is to solve the above-mentioned problem, and a stable loop is formed on the sheet S whose front end is locked by the shutter member 215, so that the sheet S can be formed.
The shutter member 215 is pushed and rotated by the strength of the waist to be retracted so that the shutter member 215 can surely pass through.

In FIG. 33, between the transport roller pair 205 and the transport roller pairs 213 and 214, a transport guide surface G201 serving as a sheet guide having a predetermined curvature is opposed and
A flapper member 222 having a guide surface 222a having a curvature corresponding to the curvature of the transport guide surface G201 is rotatably provided so as to be able to approach / separate from the transport guide surface G201.

As shown in FIG. 33, the center of rotation of the flapper member 222 is disposed near the extension line of the nip portion of the pair of transport rollers 205, and the sheet S is transported along the transport guide surface G201, Until the leading edge of S enters the shutter member 215, the flapper member 222 is set to the state position shown by the solid line in FIG.

The leading edge of the sheet S is the shutter member.
When the sheet S contacts the 215 and is locked and the sheet S forms a loop, the flapper member 222 is pivotally opened to the state position shown by the broken line in FIG. 33, and the sheet S is necessary for skew correction of the sheet S. Set so that a sufficient loop can be formed.

The flapper members 222 are arranged at least at two or more positions on the same line in the width direction of the sheet S corresponding to the width of the sheet S to be conveyed, and at least both side ends of the sheet S to be conveyed in the sheet conveying direction. By being configured so as to be able to come into contact with the vicinity, the difference between the left and right loop amounts of the sheet S is absorbed, and on the contrary, the leading edge of the sheet S is moved before the skew correction of the sheet S is completed because the loop grows too much. Shutter member 215
Of the conveyance roller pair 213,
It is possible to prevent it from plunging into the nip portion of 214.

The flapper member 222 is the flapper member.
By contacting the sheet S by its own weight and causing the loop of the sheet S to act as a pushing force, a sufficient effect can be exhibited even with a light weight.

As another configuration, the curvature of the transport guide surface G201 shown in FIG. 33 is used to make the nip portion of the transport roller pair 205 in the region between the transport roller pair 205 and the transport roller pairs 213 and 214. By providing a space in which the sheet S can form a loop in the direction in which the curvature increases from the vicinity of the extension line of the sheet S, the sheet S forms a loop following the space, which is sufficient for correcting skew of the sheet S. It may be set so that a simple loop can be formed.

Further, instead of the flapper member 222, an elastic member that the loop formed by the sheet S follows is used as the conveyance guide surface G.
It may be arranged so as to face 201, and the sheet S may form a loop following the elastic member so that a sufficient loop necessary for skew correction of the sheet S can be formed.

[Fifteenth Embodiment] Next, the first of the other configurations will be described.
The fifth embodiment will be described with reference to FIGS. 34 and 35. Figure 34
Is a cross-sectional explanatory view showing the constitution of the image forming apparatus of the fifteenth embodiment, and FIG. 35 is a cross-sectional explanatory view of the principal part of section A203 in FIG.
The same components as those in the seventh embodiment are designated by the same reference numerals and the description thereof will be omitted.

In the present embodiment, the shutter member 215 constituting the skewed sheet correcting device is mounted on the discharge roller pair 203 to improve the alignment of the sheet S at the time of discharging the sheet S. Especially, the fixing unit 211
In the sheet S on which the toner image is fixed by the heating and pressing process, curling is likely to occur, and if the sheet S is discharged with the curl formed, the alignment of the sheet S is deteriorated.

Therefore, a loop is formed on the sheet S before the discharge roller pair 203 to correct skew of the sheet S, and at the same time, a shutter member 215 constituting a skew sheet correcting device.
By adding the function of removing the curl of the sheet S by the cooperation of the sheet discharge roller pair 203 with the sheet, it is possible to improve the alignability and stackability of the sheet S when the sheet S is discharged.

As shown in FIG. 35, the rotating shaft 203c of one discharge roller 203a of the discharge roller pair 203 which serves as the sheet conveying means.
A shutter member 215 having substantially the same structure as that of the seventh embodiment is provided in the apparatus main body frame 21 so as to be rotatable around the rotary shaft 203c.
The other end of the biasing spring 225, one end of which is fixed to 7, is engaged with one end of the shutter member 215.

The shutter member 215 comes into contact with the leading end of the sheet S conveyed by the discharge roller pair 202 serving as the sheet conveying means by the urging force of the urging spring 225, as shown by the solid line in FIG. Is set to a first posture position capable of locking the tip of the.

Then, the leading edge of the sheet S conveyed by the discharge roller pair 202 pushes the shutter member 215 to rotate the shaft.
When the shutter member 215 is retracted by rotating it about the 203c, the shutter member 215 is contacted with the contact portion 215f formed at one end of the shutter member 215 as shown by the broken line in FIG.
Is brought into contact with the apparatus main body frame 217 and is set to a second posture position where the sheet S can be passed.

The discharge roller pair 202 and the discharge roller pair 20
3 and a conveyance guide surface G202 serving as a sheet guide having a predetermined curvature, and a conveyance guide surface forming a space 226 having a shape corresponding to the loop shape formed by the sheet S facing the conveyance guide surface G202. G203 is provided.

The transport guide surfaces G202 and G203 form a space 226 in which the transport guide surface G203 bulges in the leftward direction in FIG. 35 from the extension line of the nip portion of the discharge roller pair 202. The S loop can be positively formed.

With the above structure, the sheet S is a pair of discharge rollers.
When the leading edge of the sheet S is conveyed by 202 and abuts against the abutting surface 220a of the shutter member 215 held in the first posture position by the urging force of the urging spring 225, the sheet S is held in the space 226. To form a loop within.

When the loop of the sheet S comes into contact with the conveyance guide surface G203, the leading end of the sheet S is released by the shutter member.
Press 215 to rotate around the rotary shaft 203c to retract it,
The sheet S passes through the shutter member 215 and passes through the discharge roller pair.
It enters the nip part of 203 and is nipped and conveyed.

At this time, the shutter member 215 is held in the second position shown by the broken line in FIG. 35, and the direction in which the sheet S enters the nip portion of the discharge roller pair 203 and the shutter member
An angle θ formed by the ironing surface 215g of 215 is set to a predetermined angle. As a result, the sheet S is squeezed by the action of the nip portion of the discharge roller pair 203 and the squeezing surface 215g of the shutter member 215 to remove the curl, and then is discharged to the outside of the machine.

Since the direction of the curl formed on the sheet S differs depending on various image forming apparatuses, the urging force of the urging spring 225, the ironing angle θ, the regulating direction of the shutter member 215, etc. are set in correspondence with the various image forming apparatuses. By appropriately changing, skew correction and curl removal of the sheet S can be performed at one time corresponding to various image forming apparatuses.

In this embodiment, the sheet skew feeding correction device is
In addition to the skew feed correcting action of the sheet S, the curl removing action can be exerted to improve the alignment property and stacking property of the sheet S when the sheet S is discharged.

In the above embodiment, the sheet skew correcting device is provided in the discharge portion of the sheet S, but the invention is not limited to this, and the sheet skew correcting device may be provided at a desired position on the conveying path of the sheet S. The same effect can be obtained by disposing one or more.

Further, in each of the above-described embodiments, the case where the invention is applied to the image forming apparatus equipped with the electrophotographic image forming means as the image forming means has been described. However, as another configuration, an ink jet head or a thermal head is provided. It can also be applied to an image forming apparatus equipped with the image forming means.

Further, in each of the above-described embodiments, the case is described in which the sheet is a recording sheet and is applied to an image forming apparatus having an image forming means. However, as another configuration, the sheet is a sheet-like document and the sheet is a sheet. It is also possible to apply the present invention to a sheet conveying device equipped in an image reading device having an image reading means for reading the image information of a sheet document.

[0248]

Since the present invention has the above-described structure and operation, by locking the first opening / closing portion in the opened state by the click means, the first opening / closing portion is prevented from wobbling and the first opening / closing portion is prevented from wobbling. The second opening / closing portion can be opened with respect to the first opening / closing portion, and the operability of the jam processing of the sheet S can be improved.

Further, since the surface cam portion and the engaging portion corresponding to the surface cam portion are provided on the hinge members on the apparatus main body side and the first opening / closing portion side, respectively, the clicking means can be performed without increasing the number of parts. Can be configured, and the cost can be reduced.

Further, by inverting the sheet S at the time of discharging the back surface in the inverting path including the intermediate tray portion, it is possible to save space, downsize the apparatus, and further reduce the cost.

Further, by providing the curl removing means in the common path of the reverse path at the time of discharging the back surface and the re-feeding path at the time of multiplex double-sided, it is possible to mount the back surface by one curl removing means and perform the double-sided duplex It is possible to improve the separability from the photosensitive drum at the time of image formation on the second surface.

[Brief description of the drawings]

FIG. 1 is a cross-sectional explanatory view showing an overall configuration of a first embodiment of an image forming apparatus including a sheet conveying device according to the present invention.

FIG. 2 is a perspective view showing a state in which a sheet discharging unit of the first embodiment is opened.

FIG. 3 is a plan view illustrating a state in which a sheet discharging unit according to the first embodiment is opened.

FIG. 4 is a cross-sectional explanatory view showing a configuration of a click means of the first embodiment shown in a C portion in FIG.

FIG. 5 is an explanatory plan view showing a state in which a sheet discharging unit of the second embodiment is opened.

6 (a) to 6 (c) are cross-sectional explanatory views showing the configuration of the click means of the second embodiment shown in the D section in FIG.

FIG. 7 is a configuration explanatory diagram of an image forming apparatus according to a third embodiment.

FIG. 8 is a configuration explanatory diagram of an image forming apparatus according to a fourth embodiment.

FIG. 9 is an explanatory diagram of a configuration of curl removing means.

FIG. 10 is a configuration explanatory view of a curl removing unit according to a fifth embodiment.

FIG. 11 is a cross-sectional explanatory diagram of an image forming apparatus according to a sixth embodiment.

FIG. 12 is an explanatory side sectional view showing the structure of a conveyor belt according to a sixth embodiment.

FIG. 13 is a block diagram illustrating a main part of a control system of a sheet conveying device according to a sixth embodiment.

FIG. 14 is a flowchart of a control system in the sheet conveying apparatus of the sixth embodiment, and is a flowchart showing a sequence when a sheet is fed from a manual feed port.

FIG. 15 is a flowchart of a control system in the sheet conveying apparatus of the sixth embodiment, and is a flowchart showing a sequence when a sheet is fed from a sheet cassette.

FIG. 16 is a cross-sectional explanatory diagram illustrating an image forming apparatus according to a seventh embodiment.

FIG. 17 is a perspective view showing the configuration of a skewed sheet correcting device according to a seventh embodiment.

FIG. 18 is a plan view showing the configuration of a skewed sheet correcting device according to a seventh embodiment.

FIG. 19 is an operation explanatory view of the skewed sheet correcting device according to the seventh embodiment.

FIG. 20 is an operation explanatory view of the skewed sheet correcting device according to the seventh embodiment.

FIG. 21 is an operation explanatory view of the skewed sheet correcting device according to the seventh embodiment.

FIG. 22 is a diagram illustrating a skewed sheet correcting device according to a seventh embodiment.
It is a plane explanatory view showing a mode corresponding to a different sheet width.

23A is a horizontal cross-sectional explanatory view showing the outer shape of the abutting surface of the shutter member of the seventh embodiment, and FIG.
It is a horizontal cross-section explanatory drawing which shows the external shape of the abutting surface of the shutter member of embodiment.

FIG. 24 is a vertical cross-sectional explanatory view showing the outer shape of the abutting surface of the shutter member of the ninth embodiment.

FIG. 25 is a plan view showing the configuration of a skewed sheet correcting device according to a tenth embodiment.

FIG. 26 is an explanatory cross-sectional view illustrating the configuration of the skewed sheet correcting device according to the tenth embodiment.

27 is an enlarged perspective view of a portion A201 in FIG. 25, which is a diagram showing a main part of a reaction force switching means of a biasing means.

FIG. 28 is a plan view showing the configuration of the skewed sheet correcting device according to the eleventh embodiment.

29A and 29B are cross-sectional explanatory views showing the configuration of the skewed sheet correcting device according to the eleventh embodiment.

FIG. 30 is a cross-sectional explanatory diagram illustrating the configuration of the image forming apparatus according to the twelfth embodiment.

FIG. 31 is an arrow view of an A202 portion in FIG. 30.

FIG. 32 is an explanatory cross-sectional view illustrating the configuration of the image forming apparatus according to the thirteenth embodiment.

FIG. 33 is a cross-sectional explanatory diagram illustrating the configuration of the image forming apparatus according to the fourteenth embodiment.

FIG. 34 is an explanatory cross-sectional view illustrating the configuration of the image forming apparatus according to the fifteenth embodiment.

FIG. 35 is an explanatory cross-sectional view of an essential part of a portion A203 of FIG. 34.

FIG. 36 is a diagram illustrating a first conventional example.

FIG. 37 is a diagram illustrating a first conventional example.

FIG. 38 is a diagram illustrating a second conventional example.

[Explanation of symbols]

1 ... Image forming apparatus main body, 2a, 2b ... Sheet cassette,
3a, 3b ... Pickup rollers, 4 ... Sheet feeding path,
5 ... Photosensitive drum, 6 ... Original platen, 7 ... Scanning optical system, 8 ...
Image reading means, 9 ... Laser scanner, 10, 11 ... Reflecting mirror, 12 ... Charging device, 13 ... Developing device, 14 ... Registration roller pair,
15 ... Transfer charger, 16 ... Conveyor belt, 17 ... Fixing device, 17a
... Fusing roller, 17b ... Pressure roller, 18 ... Sheet discharging section,
19, 20, 21, ... Bin, 22 ... First discharge path, 23 ... Discharge roller pair, 24 ... Flapper, 25 ... Second discharge path, 26 ... Third discharge path, 27 ... Flapper, 28, 29, 30 ... Ejection roller pair, 31 ... Fourth ejection passage, 32, 33 ... Ejection roller pair, 34 ... Hinge member,
35 ... 1st opening / closing part, 36 ... 2nd opening / closing part, 37 ... Hinge piece,
37a ... Hinge pin, 37b ... Side end part, 37c ... Hole, 37d ... Top surface, 37e ... Surface cam, 38 ... Hinge piece, 38a ... Hole, 38b ... Stopper part, 38c ... Positioning hole, 38d, 38e ... Hole, 38f,
38g ... Bent part, 39 ... Leaf spring, 40 ... Click ball, 50, 51 ...
Sheet cassette, 52, 53 ... Delivery roller, 54, 55 ... Separation roller, 56 ... Registration roller, 57 ... Photosensitive drum, 58
... Transfer charger, 59 ... Platen glass, 60 ... Original, 61 ... Illumination lamp, 62a to 62f ... Mirror, 63 ... Lens, 64 ... First
Developing device, 65 ... Second developing device, 66 ... Conveying device, 66a-66c ...
Conveying rollers, 67 ... Fixing device, 68 ... Conveying rollers, 69 ... Ejecting roller pair, 70 ... Flapper, 71 ... First re-feeding path, 72 ... Intermediate tray section, 72a ... Placing section, 73 ... Conveying roller pair, 74 ... Inversion path, 75 ... Second re-feeding path, 76, 77 ... Conveying roller pair,
78 ... Spindle, 79 ... Separation flapper, 80 ... Conveying roller pair, 81 ...
Re-feeding path, 82 ... Re-feeding path, 83 ... Conveying roller pair, 83a ...
Rollers, 83b, 83c ... Followed rollers, 84 ... Arrows, 85b, 85c
… Followed roller, 85… Koshi, 101… Sheet cassette, 102…
Pickup roller, 103 ... Intermediate roller pair, 104 ... Registration roller pair, 105 ... Pre-feed sensor, 106 ... Registration sensor, 107 ... Laser scanner, 108 ... Photosensitive drum, 109 ... Process cartridge, 110 ... Transfer roller,
111 ... Fixing device, 112 ... Ejection roller pair, 113 ... Ejection tray, 114 ... Ceramic heater, 115 ... Film guide,
116… Stay, 117… Film, 118… Pressure roller, 11
9 ... Ejection sensor, 120 ... Conveyor belt, 120a ... Protrusion, 12
1, 122… Drive roller, 123… Manual feed roller, 124
... Middle plate, 125 ... Separation pad, 126 ... Separation claw, 127 ... Fixing roller, 128 ... Sheet size sensor, 129 ... Control section,
130, 131 ... Sheet path, 132 ... Jam detection means, 201
... Feeding roller, 202, 203 ... Ejection roller pair, 203a ... Ejection roller, 203c ... Rotary shaft, 204 ... Control unit,
205 ... Conveying roller pair, 206 ... Laser scanner, 207 ... Process cartridge, 208 ... Photosensitive drum, 208a, 208b
… Dowel, 209, 210… Sensor, 210a… Sensor flag, 21
0b ... Shaft, 210c ... Detection part, 211 ... Fixing unit, 212 ... Transfer charger, 213, 214, 213A, 214 A, 213 B, 214
B, 213 C, 214 C ... Conveying roller pair (213 ... Conveying roller,
214 ... Conveying roller), 214a ... Rotating shaft, 215, 215a to 215
d, 215 A, 215 B, 215 C ... Shutter member, 215e ...
End face, 215f ... Abutting part, 215g ... Ironing face, 215h ... Abutting face,
216 ... Coupling member, 216a ... Sensor flag, 217 ... Device body frame, 218 ... Rotating shaft, 219 ... Auxiliary roller, 219a ... Shutter member regulating surface, 220a, 220b, 220c ... Abutting surface, 22
0d ... Groove portion, 221a, 221b ... Sheet conveying path, 222 ... Flapper member, 222a ... Guide surface, 223a, 223b ... Projection portion, 224 ... Torsion coil spring, 224a, 224b ... End portion, 225 ... Energizing spring,
226 ... Space, A ... Image reading unit, B ... Image forming unit, A
101, B101 ... nip, B201 ... confluence, C101 ... apparatus body, C201 ... central, G201, G202, G203 ... conveying guide _{surface, S, S 1, S 2} , S 3 ... sheet, U, U20
1, U202 ... Feeding unit

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location B65H 15/00 B65H 15/00 E 29/58 29/58 B 29/70 29/70 85/00 85/00 H04N 1/00 108 H04N 1/00 108Q

Claims (9)

[Claims] 1. A sheet transporting device having a first opening / closing portion that can be opened and closed with respect to an apparatus main body, and a second opening and closing portion that can be opened and closed with respect to the first opening and closing portion, wherein the first opening and closing device is provided. Means for opening the second opening / closing part to the device body and locking the first opening / closing part to the device body at a position where the second opening / closing part can be opened / closed with respect to the first opening / closing part. A sheet conveying device characterized by being provided with. 2. The first opening / closing portion is configured to be opened / closed by a hinge member with respect to the apparatus main body, and the click means is provided on the hinge member. Sheet transport device. 3. The click means is a hinge member or the first member provided on the apparatus body side.
Has a click member capable of projecting / depressing on either one of the hinge members provided on the opening / closing part side of the hinge member, or the hinge member provided on the device body side or the first member.
A hole that can be fitted into the click member is provided on the other side of the hinge member provided on the opening / closing part side of the device, and when the click member is fitted into the hole, the first opening / closing part is attached to the device body. The sheet conveying device according to claim 2, wherein the sheet conveying device is configured to be locked in an opened state. 4. The hinge means or the first member provided on the apparatus main body side,
Has a surface cam portion on either one of the hinge members provided on the opening / closing portion side, and the hinge member provided on the device main body side or the first
First and second engaging portions that can be engaged with the surface cam portion are provided on the other side of the hinge member provided on the opening / closing portion side of the surface cam portion, and the surface cam portion is engaged with the first engagement portion. At this time, the first opening / closing part is locked in a closed state with respect to the apparatus main body, and when the surface cam part is engaged with the second engaging part, the first opening / closing part is The sheet conveying apparatus according to claim 2, wherein the sheet conveying apparatus is configured to be locked in an opened state with respect to the apparatus main body. 5. The first means by the action of the click means
When the opening / closing part of the device is locked in the open state with respect to the device body, the hinge member is provided on either the hinge member provided on the device body side or the hinge member provided on the first opening / closing part side. On the other hand, a stopper portion provided on the other of the hinge member provided on the apparatus body side or the hinge member provided on the first opening / closing portion side comes into contact with the rotation of the first opening / closing portion with respect to the apparatus body. The sheet conveying apparatus according to claim 3 or 4, wherein the sheet conveying apparatus is configured to regulate the operation. 6. The sheet conveying apparatus according to claim 1, wherein the first and / or second opening / closing section has a sheet conveying unit. 7. An image forming apparatus comprising the sheet conveying apparatus according to claim 1, further comprising image forming means for forming an image on a sheet according to image information. . 8. An image having an intermediate tray portion for placing and storing image-formed sheets on one side for double-sided or multiple-image formation, and a reverse discharge mode for discharging a single-sided image-formed sheet inside out. The image forming apparatus is characterized in that the reversing path for reversing and discharging the sheet and the re-feeding path in which the intermediate tray section is arranged are configured in common in the forming apparatus. 9. The image forming apparatus according to claim 8, wherein a curl removing unit for curling the sheet is provided in a common path of the reversing path and the re-feeding path.