JPH07157132A - Sheet transport device - Google Patents

Abstract

(57) [Abstract] [Purpose] Even when the sheet material is jammed while being sandwiched by the pair of conveying rollers of the first and second sheet guides, the jammed sheet is removed by only one pressure contact release operation. To be able to do. [Structure] The first and second sheet guides 11 and 41 are linked by a link mechanism 30. With this configuration,
The movable plate 45 of the second sheet guide 41 is biased to a predetermined upper position by the link mechanism 30 in the sheet conveying state. When the first sheet guide 11 is rotated rightward in the drawing to bring the pressure contact release state, the movable plate 45 is moved.
Is lowered by its own weight as the second link roller 25 of the link mechanism 30 moves downward, whereby the movable plate 4
The driven rollers 4b and 5b pivotally supported by the driving roller 5 are
When separated from a and 5a, the pressure contact state of the conveying roller pairs 4 and 5 is released. In other words, the second sheet guide 41 is also interlocked and brought into the pressure contact released state.

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 provided in the main body of an image forming apparatus such as a copying machine or a laser printer, and more particularly, to a driving roller and a driven roller forming a conveying roller pair at the time of jam processing. The present invention relates to a sheet conveying device capable of releasing a pressure contact state with.

[0002]

2. Description of the Related Art Conventionally, a sheet conveying device, which is disposed in a main body of an image forming apparatus such as a copying machine and conveys a transfer sheet from a sheet supply section to an image forming section, jams the transfer sheet when it is jammed. In order to easily remove the sheet, the sheet guide supporting the driven roller of the conveying roller pair formed by pressing the driving roller and the driven roller is configured to be capable of releasing the pressure contact. Especially, when the transfer sheet stacking cassette of the sheet supply unit is inserted from the front surface of the main body or when the cassette has a plurality of stages,
Further, in the case of a large-sized image forming unit such as a color copying machine, since the sheet conveying distance is long, a plurality of sheet guides are provided and each of them can be pressed and released.

FIG. 5 is a schematic diagram of a color copying machine provided with a conventional sheet conveying device of this type.

As shown in the figure, this sheet conveying apparatus is separated from the feed roller 112 by being kicked out from one of the upper, middle and lower three cassettes 101 in the copying machine main body 100, for example, the lowermost one by a pickup roller 111. Copy paper (sheet material) P that is separated and fed one by one by the roller 113
The photosensitive drum 201, the transfer drum 202, and the developing device 20.
It is arranged so as to be conveyed to an image forming unit composed of 3 to 206 and the like.

In this sheet conveying device, a plurality of conveying roller pairs 1, 2, 3, 4, 5 and a registration roller pair 6 are arranged along the conveying path. The driven rollers 1b, 2b, 3b on the right side of the pair of conveying rollers 1, 2, 3 arranged in the vertical path portion of the conveying path are axially supported by a first sheet guide 11 via a spring 9 and are respectively driving rollers. 1a, 2
It is in pressure contact with a and 3a. Further, the first sheet guide 11 is integrally formed with the door on the right side surface of the main body, and is rotatably provided around the shaft 10.

During the jam processing, the first sheet guide 11 is rotated together with the driven rollers 1b, 2b and 3b to the position shown by the alternate long and short dash line 11 ', whereby the driving rollers of the conveying roller pairs 1, 2 and 3 are driven. The pressure contact state between 1a, 2a, 3a and driven rollers 1b, 2b, 3b is released.

Further, the driven rollers 4b and 5b below the conveying roller pair 4 and 5 arranged in the lateral path portion of the conveying path are
The second sheet guide 41 is axially supported by a spring 9 and is in pressure contact with the drive rollers 4a and 5a, respectively. Further, the second sheet guide 41 is rotatably provided around the shaft 40, and is rotated by the rotation operation of the lock lever 90.

At the time of jam processing, the second sheet guide 41 rotates together with the conveying driven rollers 4b and 5b to the position shown by the chain line 41 ', whereby the driving rollers 4a and 5a of the conveying roller pairs 4 and 5 are rotated. And the driven roller 4b,
The pressure contact state with 5b is released.

In this color copying machine, an image is formed on the copy sheet P conveyed to the registration roller pair 6 by the sheet conveying device as follows.

First, the copy sheet P is attracted onto the transfer drum 202 by the attraction roller 7 and rotated. During this rotation, a latent image is formed on the photosensitive drum 201 according to image information sent from an output device (not shown) such as a document reading device or a computer, and the latent image is magenta, which forms the developing device. The developing devices 203, 204, 205, and 206 for cyan, yellow, and black are successively developed. The toner image is transferred to the copy paper P on the transfer drum 202 each time each color is developed, and a full-color image is formed on the copy paper P.

After that, the copy paper P on the transfer drum 202 is separated from the transfer drum 202 by the separation claw 209, conveyed on the conveying unit 210 and sent to the pair of fixing rollers 207 and 208, and at the nip portion thereof, a full color image is formed. The image is fixed and discharged by the paper discharge roller pair 211 to the outside of the apparatus.

[0012]

SUMMARY OF THE INVENTION As described above,
In the sheet conveying device including the second two sheet guides 11 and 41, when a jam occurs, depending on the location where the jam occurs, the jam sheet cannot be removed unless the both sheet guides 11 and 41 are pressed and released. There is.

For example, in the color copying machine shown in FIG. 5, when the copy sheet P is jammed from the conveying roller pair 3 to the conveying roller pair 4, even if only the first sheet guide 11 is released from the pressure contact, The leading edge of the copy sheet P is still held by the pair of transport rollers 4, and the copy sheet P cannot be easily removed. Further, even if only the second guide 41 is released, the trailing edge of the copy sheet P is still held by the pair of transport rollers 3, and the copy sheet P cannot be easily removed.

Therefore, the front door of the main body is opened, and the lock lever 9
0 must be rotated to release the second sheet guide 41, and further release the first sheet guide 11 which is integrally formed with the door on the right side surface of the main body to remove the jammed copy paper P. I have to.

That is, in the above-described conventional sheet conveying device, when the sheet material is jammed while being sandwiched between the conveying roller pair of the first sheet guide and the conveying roller pair of the second sheet guide, two sheets are jammed. There is a problem in that the jam clearance work is complicated because the two sheet guides must be released from the pressure contact separately.

The present invention has been made to solve such a problem, and also when the sheet material is jammed while being sandwiched between the conveying roller pairs of the first and second sheet guides. An object of the present invention is to provide a sheet conveying device that can remove a jammed sheet with a single press contact release operation and that can easily perform a jam treatment.

[0017]

In order to achieve the above object, in the sheet conveying apparatus according to the present invention, one of the first and second sheet guides (11, 41) is brought into a pressure release state. Thus, the sheet guide interlocking means (30, 50) for interlocking the other side to bring them into the pressure contact released state is provided.

[0018]

In the sheet conveying apparatus having the above structure, when one of the sheet guides (11) is released from the pressure contact state, the sheet guide interlocking means (30, 50) interlocks with the other sheet guide (41) to release the pressure contact state. Therefore, even if the sheet material is jammed while being sandwiched by the pair of conveying rollers of the first and second sheet guides (11, 41), the jammed sheet can be removed by one pressing contact release operation. Can be removed.

The reference numerals in the above parentheses are for comparison with the drawings and do not limit the structure of the present invention.

[0020]

Embodiments of the present invention will be described below with reference to the drawings. <Embodiment 1> FIG. 1 is a schematic configuration diagram of a sheet conveying apparatus according to Embodiment 1 of the present invention, which is disposed in the main body of a color copying machine (image forming apparatus). FIG. FIG. 3 and FIG. 3 are side views of the second sheet guide in the same sheet conveying device. It should be noted that, of these configurations in FIGS. 1 to 3, the same reference numerals are given to the parts that are not different from the conventional example shown in FIG.

This sheet conveying device is ejected from one of the upper, middle, and lower cassettes 101 in the main body of the copying machine, for example, the lowermost stage by a pickup roller 111 and is fed by a feed roller 112 and a separation roller 113. The copy sheets (sheet materials) P, which are separately fed sheet by sheet, are arranged to be conveyed to an image forming unit (not shown).

In the figure, 11 is a first sheet guide, 41 is a second sheet guide, the first sheet guide 11 has three driven rollers 1b, 2b, 3b, and the second sheet guide 41 is The two driven rollers 4b and 5b are axially supported so as to be in pressure contact with the corresponding driving rollers 1a to 5a via springs 9, respectively. Each drive roller 1a-5a
And the driven rollers 1b to 5b form the conveying roller pairs 1 to 5.

The first sheet guide 11 is rotatable about the shaft 10. If the hook 12 is rotated in the direction of arrow A to release the engagement with the pin 13, the first sheet guide 11 is moved in the direction of arrow B. The driven rollers 1b, 2b, and
It is possible to release the pressure contact state of the conveying roller pairs 1, 2 and 3 by separating 3b from the corresponding drive rollers 1a, 2a and 3a. That is, at the time of jamming, the jammed sheet left on the portion of the first sheet guide 11 can be removed.

Further, at the upper end portion of the first sheet guide 11, the pressing pin 15 is directed toward the second sheet guide.
Is provided.

The second sheet guide 41 on one side is provided with a shaft 40.
The lock arm 92 is rotated in the direction of the arrow C by the lock lever 90, and the roller 91 pivotally supported by the tip of the lock arm 92 and the guide side plate 42 of the sheet guide 41. When it is disengaged from the drive rollers 4a and 5a, the driven rollers 4b and 5b that are rotatably supported can be separated from the corresponding drive rollers 4a and 5a, and the conveying roller pairs 4 and 5 can be pressed against each other. Can be canceled. That is, at the time of jamming, the jammed sheet left in the portion of the second sheet guide 41 can be removed.

Here, the guide side plate 42 is rotatable with respect to the shaft 40 fixed to one end of the upper side plate 43, and is biased upward in the figure by the roller 91 and the lock arm 92. The smooth edge surface 42a provided on the guide side plate 42 is positioned by abutting the smooth edge surface 43a provided on the bent portion of the side plate 43.

A movable plate 45 is attached to the guide side plate 42 so as to be vertically movable, and the driven rollers 4b and 5b are pivotally supported on the movable plate 45. This movable plate 45
Is the vertically long holes 42b, 42c provided in the guide side plate 42.
In addition, it is supported by the two step screws 33 and 34 so as to be movable up and down by the length of the vertically elongated holes 42b and 42c. On the other hand, the guide plate 46 of the second sheet guide 41
Of the upper guide plate 47 and the drive roller 4a,
5a is supported by the upper side plate 43.

The movable plate 45 of the second sheet guide 41 is urged upward by a link mechanism (sheet guide interlocking device) 30 provided on the guide side plate 42 in the sheet conveying state, and the movable plate 45 is moved upward. The projections 45a and 45b provided on the upper end of the 45 are positioned by hitting the upper guide plate 47. Thereby,
The distance between the guide plate 46 integrated with the movable plate 45 of the sheet guide 41 and the upper guide plate 47 is kept constant.

The link mechanism 30 includes a push plate 21, a first link rod 22, a first link roller 23, a second link rod 24,
It is configured by connecting the second link roller 25, the third link rod 26, and the third link roller 27. The first link rod 22 is supported by a bracket 31 fixed to the guide side plate 42 so as to be able to move forward and backward, and between the bracket 31 and the push plate 21, the push plate 21 is located on the right side, that is, the first sheet guide 11 A spring 32 for urging the spring is provided.
Further, the first link roller 23 and the third link roller 27 are
The laterally long holes 42d and 42e formed in the guide side plate 42 are movably engaged with each other. Furthermore, the horizontally long hole 4
A spring 35 that biases the engaged third link roller 27 to the right is provided in 2e.

In the above structure, the push plate 21 of the link mechanism 30 has the first sheet guide 11 in the sheet conveying state.
Is pressed leftward in the figure, and the first link roller 23 is moved leftward via the first link rod 22. On the other hand, since the third link roller 27 receives a force to the right by the spring 35, as a result, the second link roller 2
5 is moved upward to urge the movable plate 45 of the second sheet guide 41 upward.

When the first sheet guide 11 is opened and brought into the pressure contact released state, the push plate 21 of the link mechanism 30 is released.
However, the spring 32 between the bracket 31 and the bracket 31 moves to the right, and as a result, the second link roller 25 is moved downward, and the movable plate 45 of the second sheet guide 41 descends by its own weight. As a result, the driven rollers 4b and 5b axially supported by the movable plate 45 separate from the drive rollers 4a and 5a,
The pressure contact state of the conveying roller pairs 4 and 5 is released.

That is, in the sheet conveying apparatus having the above-described structure, by bringing one of the first sheet guides 11 into the pressure contact released state, the other second sheet guide 41 is also interlocked with the pressure release state. it can. Therefore, even when the copy sheet P is jammed while being sandwiched between the conveying roller pairs 3 and 4 of the first and second sheet guides 11 and 41, the jammed sheet is removed by only one pressure contact release operation. can do. Of course, the respective sheet guides 11 and 41 may be separately brought into the pressure release state.

The spring 35 is used for the second sheet guide 4
The movable plate 45 of 1 and the driven rollers 4b and 5b, which are determined by the spring 9, overcome the pressure contact force of the driven rollers 4b and 5b to the drive rollers 4a and 5a, and urge the second link roller 25 upward. There is a need.

Further, the laterally long holes 42d of the guide side plate 42 for engaging the first link roller 23 and the third link roller 27,
In consideration of the movement amounts of the rollers 23 and 27, the laterally long hole 42d with which the first link roller 23 is engaged is formed longer in 42e. <Embodiment 2> FIG. 4 is a schematic view of the essential parts of a sheet conveying apparatus according to Embodiment 2 of the present invention. In addition, in FIG. 4, parts that are not different from the configuration of the first embodiment are
The same reference numerals are given and the description is omitted.

As shown in the figure, in this sheet conveying device,
The movable plate 45 of the sheet guide 41 of FIG.
The step screws 33 on the side of the first sheet guide 11 are supported by the guide side plate 42 by 3, 34, and are inserted into the vertically long holes 42f formed in the movable plate 45, and the step screws 3 on the opposite side.
Reference numeral 4 supports the movable plate 45 further outside the pair of transport rollers 5 on the same side. This allows the movable plate 45 to move to the first
It is configured such that it can be rotated by a certain amount around the step screw 34 on the side opposite to the sheet guide 11. In addition, the movable plate 45
Of the leaf spring 39 at the lower end of the first sheet guide 11 side.
Is attached.

On the other hand, a cam 16 is projectingly provided at the upper end of the first sheet guide 11 toward the second sheet guide 41.

The cam 16 of the first sheet guide 11
And the leaf spring 39 of the movable plate 45 of the second sheet guide 41.
And constitutes a cam mechanism 50 for interlocking both sheet guides 11 and 41.

In the sheet conveying state, the movable plate 45 of the second sheet guide 41 is urged upward due to the cam 16 of the cam mechanism 50 being pressed against the lower surface of the plate spring 39 to move. The projection 45b provided on the upper end of the plate 45 is positioned by abutting the upper guide plate 47.

Further, when the first sheet guide 11 is opened and brought into the pressure release state, the cam 16 of the cam mechanism 50 separates from the leaf spring 39, so that the movable plate 45 of the second sheet guide 41 weights itself. To rotate downward. As a result, the driven rollers 4b and 5b pivotally supported by the movable plate 45 are separated from the drive rollers 4a and 5a, and the pressure contact state of the conveying roller pairs 4 and 5 is released.

That is, also in the case of the sheet conveying apparatus according to this embodiment, one of the first sheet guides 11 is brought into the pressure release state so that the other second sheet guide 41 is released.
The pressure contact can be released by interlocking with. Therefore, even when the copy sheet P is jammed while being sandwiched between the pair of conveying rollers 3 and 4 of the first and second sheet guides 11 and 41, the jammed sheet is removed by only one pressure contact release operation. can do. Of course, the respective sheet guides 11 and 41 may be separately brought into the pressure release state.

The leaf spring 39 attached to the movable plate 45 of the second sheet guide 41 is driven by the weight of the movable plate 45 and the driven rollers 4b and 5 determined by the spring 9.
It must be strong enough to overcome the pressure contact force of b with the drive rollers 4a and 5a and urge the movable plate 45 upward.

[0042]

As described above, according to the sheet conveying apparatus of the present invention, since the sheet guide interlocking means is provided, the sheet material is sandwiched between the conveying roller pairs of both the first and second sheet guides. Even when the jam is caused in the state of being jammed, the jam sheet can be removed by only one pressing contact release operation. Therefore, it becomes possible to easily perform the jam processing.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a sheet conveying apparatus according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of a main part of FIG.

FIG. 3 is a side view of a second sheet guide in the same sheet conveying device.

FIG. 4 is a schematic configuration diagram of a main part of a sheet conveying apparatus according to a second embodiment of the present invention.

FIG. 5 is a schematic configuration diagram of a color copying machine (image forming apparatus) including a conventional sheet conveying device.

[Explanation of symbols]

 1-5 Conveying roller pair 1a-5a Drive roller 1b-5b Judo roller 11 First sheet guide 30 Link mechanism (sheet guide interlocking means) 41 Second sheet guide 50 Cam mechanism (sheet guide interlocking means)

Claims (3)

[Claims] 1. A plurality of conveying roller pairs, which are provided along a sheet conveying path in an image forming apparatus main body and are composed of a driving roller and a driven roller that are in pressure contact with each other, and a driven roller of the plurality of conveying roller pairs. Are divided into two groups and are axially supported by the first and second sheet guides, respectively, and each of the sheet guides separates the driven roller that is axially supported from the corresponding driving roller and presses the pair of conveying rollers. In a sheet conveying device provided so as to be able to release the sheet guide, by interlocking one of the first and second sheet guides with the pressure contact released state, the other is also interlocked to bring the sheet guide interlocked state into the pressure contact released state. A sheet conveying device comprising means. 2. The sheet conveying apparatus according to claim 1, wherein a link mechanism is provided as the sheet guide interlocking means. 3. The sheet conveying apparatus according to claim 1, wherein a cam mechanism is provided as the sheet guide interlocking means.