JPH11314793A - Paper conveying method for image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper feeder which is designed to easily perform the disposal of a paper jam caused in a paper feeding route to an intermediate tray, in a simple manner. SOLUTION: In a paper conveying means to be composed of both first and second paper conveying passages, this second paper conveying passage is provided with a rotational means 40 rotating one side conveying guide 31, two conveying rollers 39 and 35 being installed each in both the conveying guides 31 and nippingly conveying a sheet of paper, and a biasing means 38 energizing at least one side of these conveying rollers 39 and 35 in the paper nipping direction, and further, in linkage with the route opening of the first paper passage by a body cover, the one side conveying guide 31 is constituted so as to be rotated in a direction of weakening a paper nipping force by the biasing means 38.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electrostatographic copying machine,
The present invention relates to a sheet conveying means provided in an image forming apparatus such as a printer and a facsimile.

[0002]

2. Description of the Related Art In an image forming apparatus which is capable of forming a two-sided image, for example, when a mode for forming a two-sided image is selected, the above-mentioned sheet conveying means is used to transfer a sheet having an image formed on one side to an intermediate position. It is arranged from the fixing device to the intermediate tray to temporarily stock the tray.

As this sheet conveying means, a first sheet conveying path composed of a pair of conveying guides in which one conveying guide can be opened integrally with the image forming apparatus main body cover, and one conveying guide rotates inside the main body. And a second paper transport path comprising a pair of operable transport guides.

In the paper transport means having such a configuration, when the main body cover is opened when the paper is jammed in the transport path, the transport path of the first paper transport path is opened accordingly. The paper jammed in the transport path can be easily removed, and the paper jammed in the second paper transport path can be easily pulled out from the opening of the main body cover.

By the way, the second paper transport path is provided with transport rollers which are elastically pressed against each other by urging means in order to forcibly transport the paper after image formation to the intermediate tray. When a sheet jams while being nipped by the transport rollers, if the sheet is forcibly pulled out, the sheet may be torn, and it may be difficult to remove the remaining torn sheet.

Therefore, conventionally, one transport guide of the second paper transport path is rotatably provided so that the transport path can be opened, and biasing means for elastically pressing the transport rollers against each other is provided. When the conveyance path is opened, the paper nip force by the urging means is reduced when the conveyance path is opened, so that the paper jammed in the conveyance path is nipped by the conveyance rollers. In this case, the jam can be cleared without causing the sheet to tear.

[0007]

However, it takes a lot of time to open the main body cover and open the transport path against the urging force of the urging means, and to maintain the open state of the transport path. In addition, it was very troublesome to perform the jam processing.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and has as its object to provide a sheet conveying means which can easily and easily carry out jam processing by simple and rational improvement. The purpose is.

[0009]

In order to solve the above-mentioned problems, the present invention provides a sheet conveying means having the above-mentioned first and second sheet conveying paths. A rotating unit for rotating one of the transport guides, a transport roller provided on the transport guide for nip transporting the paper, and a biasing unit for biasing at least one of the transport rollers in the paper nip direction are provided. And, in conjunction with the opening operation of the first paper transport path by the main body cover, the rotating means is rotated so that the one transport guide is rotated in a direction to weaken the paper nip force by the urging means. There is a feature in that the configuration is made as described above.

According to the above arrangement, if the main body cover is opened when the paper jams in the transport path, the transport path of the first paper transport path is opened with one touch of opening the cover. Since the one conveyance guide of the second paper conveyance path weakens the nip force of the urging means in conjunction with
Moreover, since the state where the nip force is weakened is maintained,
Even if the jammed sheet is nipped by the transport rollers, the jam can be easily removed without causing the sheet to tear.

After the jam has been cleared, the main body cover is closed, and the one of the transport guides is rotated by the rotating means in conjunction therewith, so that a pair of transport guides in the second paper transport path are provided. Is formed as before, and the urging means presses the conveying rollers elastically against each other with a predetermined nip force. Further, the first sheet conveying path also returns to the original conveying path. Will be formed.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of a full-color printer as an example of an image forming apparatus, in which a plurality of upper and lower (four in this embodiment) paper feed cassettes 1 are configured to be drawn out of the apparatus, An apparatus main body 3 having, on a lower side, a convey path 2 for a sheet to be printed.
And an image forming unit 5 having an image forming drum 4 and a sheet fed from the merging and conveying path 2.
A paper feed unit 6 that transports the paper after image formation to the fixing device 7, and a paper discharge roller pair 10 that discharges the paper after fixing to the paper output tray 9. A sheet conveying means 12 for stocking the sheets after image formation in the intermediate tray 11, and a path switching means 13 for switching and feeding the sheets to the sheet conveying means 12 and the discharge path 9. I have.

The image forming unit 5 includes a main body 3
The charging device 14 is arranged around the image forming drum 4 laid on the
And the image reading information from the optical device 15,
An exposure device 16 for forming a latent image on the drum surface, a developing device 17 for containing cyan, yellow, magenta, and black toner separately to visualize the latent image formed on the drum surface; The apparatus includes a transfer / separation unit 18 that transfers a toner image to a sheet and separates the sheet, a cleaning device 19, and a charge removing device 20.

The transfer / separation unit 18
Is a toner image transfer belt 2 formed on the drum surface.
1, a transfer / separation device 22 using rollers, and a cleaning device 23 for the transfer belt 21. When the optical device 15 scans the image of the document four times, the developing device 17 outputs cyan, yellow, magenta, and black. Are successively developed on the drum surface, and the toner images are sequentially superimposed on the transfer belt 21 so that
A full-color toner image is formed on the belt surface, and the full-color toner image is transferred to a sheet fed to the transfer / separation device 22.

The intermediate tray 11 is provided with a paper feed belt 24 for feeding out the stock paper based on the re-feed information. 25, the sheet after image formation is turned upside down and re-fed from the sheet feeding unit 6 to the transfer / separation device 22, and the sheet after image formation is
The paper discharge tray 9 passes through the fixing device 7 and the paper discharge roller pair 10.
It is configured to be taken out.

The intermediate tray 11 and the feed belt 24
And the re-transport path 25 is fixedly arranged in the apparatus main body 3, but these are unitized as shown by the imaginary line f and can be pulled out of the apparatus in the same manner as the paper feed cassette 1. With such a configuration, when a jam occurs in the arrangement portion of the sheet feeding belt 24 or the re-conveyance path 25, the unit f can be pulled out of the apparatus to easily perform the jam processing.

In the full-color printer having the above-mentioned structure, as shown in FIG. The image forming apparatus main body 3 is provided so as to be openable and closable,
2 with the upper first paper transport path 12A and the intermediate tray 11
And a pair of transport guides 29, 28 provided with paper feed rollers 27, 28, respectively, in the upper first paper transport path 12A.
Out of the 30, an outer transport guide 29 is provided on the main body cover 26 so that the transport path is opened when the main body cover 26 is opened.

Reference numeral 44 in the figure denotes locking means for fixing the main body cover 26 in a closed state. A locking pin d is provided on the side of the apparatus main body 3 and a hook e which can be disengaged from the locking pin d.
Is provided on the body cover 26 side.

As shown in FIGS. 3 and 4, the lower second paper transport path 12B to the intermediate tray 11 includes a pair of upper and lower transport guides 31 and 32 forming a transport path. A guide 32 is fixedly provided on the apparatus main body 3, and brackets 3 are provided on both sides of the transport guide 32.
The upper transport guide 31 is pivotally connected to the upper and lower transport guides 31 around the support shaft 34 on the downstream side of the transport path. The tip side (upstream side of the transport path) is configured to turn down (in the direction indicated by the arrow a in FIG. 4) toward the lower transport guide 32 based on its own weight.

A transport roller 35 is fixedly provided at the downstream side of the lower transport guide 32, and the paper feed rotating means 36 is connected thereto.
Is provided with a transport roller 39 via a biasing means 38 by a leaf spring 37 so as to elastically contact the transport roller 35.

Further, as the main body cover 26 is closed, turning means 40, 40 which are pushed down by a turning member 43 provided with the main body cover 26 are attached to the brackets 33, 33 via a support shaft 41. In addition to being pivotally mounted, the locking members 42,
42 are provided on both sides of the upper transport guide 31, and the leading end of the upper transport guide 31 is moved in accordance with the downward rotation of the rotating means 40, 40 (in the direction indicated by the arrow b in FIG. 4). It is configured to be lifted against its own weight (in the direction indicated by arrow c in FIG. 4).

According to the above configuration, the main body cover 26
In the closed state, as shown in FIG. 5 (A), the upper transport guide 31 is lifted by the rotating means 40, 40 and against its own weight, and this transport guide 31 and the lower transport guide 31 are lifted. 32, a transport path is formed, and a leaf spring 37 constituting the urging means 38 is flexed so that the upper transport roller 39 is elastically pressed against the lower transport roller 35. After the paper, both rollers 3
6 and 39, elastically nipped by the intermediate tray 1
1 will be conveyed.

When the main body cover 26 is opened in this state,
As shown in FIG. 5 (B), the turning means 4 is substantially driven in conjunction with the opening of the main body cover 26 and based on its own weight.
0, 40 turns the tip side of the upper transport guide 31 to the lower transport guide 32 side, whereby the upper and lower transport rollers 35, 3 by the urging means 38.
Nip force of 9 will be weakened.

Therefore, when the main body cover 26 is opened when a paper jam occurs in the paper transport means 12, the transport path of the first paper transport path 12A is opened and the second paper transport path is opened with one-touch labor. In 12B, since the nip force of the conveying rollers 35, 39 by the urging means 38 is weakened, and the state where the nip force is weakened is maintained, the jammed sheet is conveyed to the conveying rollers 35, 3
Even if the sheet is nipped by 9, the jam can be easily removed without causing the sheet to tear.

After the jam has been cleared, the transport guide 31 on the upper side is interlocked with the one-touch effort of closing the main body cover 26 to return to the original position by the rotating means 40, 40 against its own weight. Then, the transport path formed by the pair of transport guides 31 and 32 is returned to the original state, and the urging unit 38 also moves the transport roller 3 with a predetermined nip force.
5 and 39 are elastically pressed against each other, and the transport path of the first paper transport path 12A is formed as before.

In the above embodiment, the main body cover 2
In the open state of No. 6, the nip force of the urging means 38 is weakened so that the upper transport roller 39 abuts on the lower transport roller 35 with a weak force. Alternatively, the nip force of the urging means 38 may include a nip force of zero in the present invention.

The urging means 38 is provided between the upper conveying guide 31 and the conveying roller 39 provided on the upper conveying guide 31. The urging means 38 is connected to the lower conveying guide 32.
And a conveying roller 35 provided thereon, or an urging means 38 may be provided on both of them.

Further, in conjunction with the opening of the main body cover 26,
By rotating the upper conveyance guide 31 based on its own weight,
Although the nip force of the urging means 38 is weakened, the lower conveyance guide 32 is rotated based on its own weight in conjunction with the opening of the main body cover 26, and the urging is performed with this rotation. The nip force of the means 38 may be weakened.

[0029]

As described above, according to the paper conveying means according to the present invention, the nip force of the urging means can be reduced with one-touch effort to open the main body cover.
In addition, since the state where the nip force is weakened is maintained, even if the jammed sheet is nipped by the transport roller, the jam can be easily processed without causing the sheet to tear.

Further, after the jam clearance, the conveyance path of the second paper conveyance path by the pair of conveyance guides is formed just by closing the main body cover, and the urging means also has a predetermined nip force. Then, the transport rollers are elastically pressed against each other, and the transport path of the first paper transport path is formed as before. According to the present invention, the operability of the jam clearance is reduced as compared with the related art. An extremely excellent sheet conveying means is provided.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a full-color printer as an example of an image forming apparatus.

FIG. 2 is an explanatory diagram showing an open state of a main body cover.

FIG. 3 is an exploded perspective view of a part of a second paper transport path.

FIG. 4 is a side view showing the second sheet transport path in a state where the body cover is opened and the nip force of the urging means is weakened.

FIG. 5A is a side view of a second paper transport path showing a state where a main body cover is closed, and FIG. 5B is a side view of the second paper transport path showing a state where the main body cover is opened.

[Explanation of symbols]

26 ... body cover, 29, 30, 31, 32 ... conveyance guide, 35, 39 ... conveyance roller, 38 ... urging means, 40 ...
Rotating means.

Claims (2)

[Claims] A first paper transport path including a pair of transport guides in which one of the transport guides can be opened integrally with an image forming apparatus main body cover; and a pair of first transport guides in which one of the transport guides can rotate in the main body. And a second paper transport path comprising a transport guide of the image forming apparatus, wherein the second paper transport path includes a rotating unit configured to rotate the one transport guide; A transport roller provided on the transport guide for nip transport of the paper, and a biasing unit for biasing at least one of the transport rollers in the paper nip direction are provided, and the opening operation of the first paper transport path by the body cover is provided. A sheet conveying means of the image forming apparatus, wherein the rotating means is rotated so that the one of the conveying guides is rotated in a direction in which the sheet nip force by the urging means is weakened. 2. The urging means urges the conveying roller in a nip direction, and the rotating means moves the one conveyance guide in the urging direction of the urging means when the main body cover is closed. The one of the transport guides is rotated in a direction in which the paper nip force of the transport roller is weakened when the main body cover is opened. Sheet conveying means of the image forming apparatus.