JPS5986543A - Sheet conveying device equipped with gripper - Google Patents

Abstract

PURPOSE:To form a picture image without making a sheet dirty by allowing a picture image processing part to successively pass through while holding the sheet with a gripper and guiding it with a limiting rail in a conveying device provided with a gripper of a copying machine, etc. CONSTITUTION:A gripper 20 holding a sheet to be conveyed passes through between a photosensitive drum and a yransfer charger 25b. A transfer charger guide rails 24b is fixed on transfer unit side plates 22, 22b, guides a transfer charger 25b, and simultaneously elastically presses down onto the photosensitive drum by means of plate springs 42a, 42b. The transfer charger 25b is positioned by edges 43a, 43b with good reproducibility. The limiting rail of a chain comprises a rear side lower rail 44, a rear side upper rail 45, a front side lower rail 46, and a front side upper rail 47, and is fixed on a conveying unit side plate by means of angle materials 48-51. The limiting rails 44-47 are made of self lubricating plastic, hold the roller surface of conveying chanes 52, 53 between themselves, and also holds down the link surface to limit the meandering of the gripper 20.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a sheet conveying device for copying machines, printing machines, recording machines, and other various machines (referred to as copying machines) equipped with a mechanism for conveying sheets. The present invention relates to a sheet conveyance device having a gripper that grips and conveys a sheet.

Conventionally, in this type of apparatus, when performing image processing such as multiple transfer of images on a plurality of photosensitive drums arranged in a row onto the same sheet synchronously, the sheets are placed on a screen transfer belt. There are things that are placed and transported.

However, sheet conveyance using such belts has the disadvantage that the belt itself becomes dirty with toner images on the photosensitive drums, and the dirt adheres to the sheet, causing stains on the back side of the sheet.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a novel sheet conveying device that is improved in view of the above-mentioned drawbacks.

That is, the present invention provides a sheet conveying device having a gripper that grips and conveys a sheet.

We have developed a new gripper that has been improved to allow the gripper to transport sheets even more reliably and stably.
It is another object of the present invention to provide a sheet conveying device having the following.

That is, the main structure of the present invention that can achieve the above object is to transport a sheet to pass through a plurality of image processing units of an array of image forming means and perform multiple image processing on the sheet one after another. A sheet conveying apparatus having a gripper, wherein the conveyed sheet is gripped by a gripper and conveyed through the image processing section one after another.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a sectional view of a color printer device to which the present invention is applied.

In the figure, an optical unit (1a) is fixed to both side plates of the main body by a semiconductor laser unit (not shown), a polygon scanner unit (not shown), an fθ lens unit (2), and an optical box 3a. In FIG. 1, only the rear side plate 4 is visible. The laser light emitted from the optical unit 1a passes through the exposure window 52L and exposes the rotatably supported photosensitive drum 6a. Photosensitive drum 5
A is attached to a removable Kameko photo process unit (hereinafter referred to as process unit) 7a.

The process unit 7a consists of several subunits that accomplish the electrophotographic process. In this embodiment, the process unit 7a consists of a primary charger 8a, a developer 9a, and a cleaner 10a, and is integrally formed with a side plate 11a, and can be attached and detached in the depth direction in the figure by rails 12a and 13&. It has become. optical unit)
1 & % process unino)? 2L has the same shape,
As shown in the figure, 4 pieces are arranged in a row. From the right, yellow, magenta + 17"
g A black microscope image is transferred to the photosensitive drums 6a, 6 +, 6.
It plays the role of forming on top of c6d.

The transport unit 13 includes pantograph mechanisms 14a and 14b.
.

(only a cross section is shown) is supported so as to be movable up and down. The side plate 16 of the transport unit has sprockets at both ends)1
7 (2 front and rear), sprocket 18 (2 front and rear)
) is rotatably supported.

The above four sprockets) 17 and 18 have chain 1
9 is stretched, and idler sprockets 19□ (two at the front and rear) are provided to remove slack from the chain 19. A gripper 2 is attached to the chain 19 so that a part thereof connects the front chain and the rear chain transversely.
In the part other than the gripper, where 0 is the gripper, electrically insulated wire (product name,
(tetron, nylon, etc.) is stretched (not shown)
.

L-angle 212L is installed on the side plate of the transport unit 6.

2] J (total of 4 pieces before and after) is taken and 8 pieces, L
- A transfer charger guide rail 24a is fixed to the angles 21a and 21b (C) and the two rear transfer unit frames. The transfer charger 25a is removably fixed to the transfer charger guide rail 24a, and has a shape that does not hinder movement of the chain 19 and gripper 20. Further, the transfer charger includes four photosensitive drums 5a, 6b,
4 pieces of the same shape 25 in the positions corresponding to 6c and 6d
a, 25b, 25c, and 25a are arranged.

Photo ink converters 26a, 26b, 26
26d and 26d detect the tip of the moving gripper 2o and determine the timing of the laser beam opening.

The photointerrupters 27a and 27b detect the tip of the moving gripper 20 and determine the timing of the entire sea fence.

The cam 28a is a cam that opens the clipper 20, thereby opening the jigripper 20 to grip the transfer paper. The cam 28b similarly opens the gripper 20, releases the transfer paper from the gripper, and transfers the transfer paper to the separating claw 29.

The paper feed tray 30 is fixed to the side plate 4 of the main body and serves to guide the transfer paper. The paper feed guide 31 is connected to the paper feed tray 30
It works together with the guide to guide the transfer paper.

The paper feed guide 31 with '=1' is configured to be removable in case the transfer paper jams. Paper feed guide 3
2.33 is identified on the side plate 4 of the main body like the paper feed tray 30, and guides the transfer paper together with the paper feed guides 34 and 35. The paper feed guides 34 and 35 are also configured to be retractable in case the transfer paper jams.

The photo ink converter 36 detects the leading edge of the transfer paper and generates a print sea fence start signal. The pair of paper feed registers 37 can be set to stop or rotate at a constant speed using a drive source and a clutch (not shown).

A pair of paper feed registers 38 are operated by a drive source and two clutches (not shown), which allow the paper feed registers to stop, rotate at a constant speed, and rotate at a constant low speed.
There are many modes to choose from.

The fixing device 3B is housed in a heat insulating frame, the upper roller 39 has a core metal coated with Teflon, and the middle roller 40 has a core metal covered with silicone rubber. The lower opening 241 has a core metal coated with Teflon. The fixing device 38 is of a well-known so-called heat roller fixing type.

Next, the operation of the apparatus of this embodiment will be explained. First, when the power is turned on, a laser (not shown) and a scanner 1&, which are inside the optical box 3, are activated sequentially from the right in FIG. At the same time, the heater located inside the fixing device is also energized. The printer is ready when the laser is turned on, the scanner reaches a predetermined rotation speed, and the fixing roller 38 reaches a predetermined temperature. When the transfer paper is inserted onto the paper feed guide 30, a start signal for the photo ink printer 36 is generated.

The photosensitive drums 6a, 5b, 6c are activated by the start signal.

6d begins to rotate, and at this time the pair of paper feed registers 37 are in a stopped state.

Next, the gripper 20 starts running due to the rotation of sprockets l'i' and 1B.

When the clipper 20 passes the photo interrupter 27a, the pair of paper feed registers 37 rotates at a constant speed, and the transfer paper reaches the pair of paper feed registers 33 along the paper feed guide 32, but at this time, the pair of paper feed registers 38 stop. Therefore, the transfer paper forms a loop between the pair of paper feed registers 37 and 38. A pair of paper feed registers 38 are connected to a photo interrupter 27.
After a predetermined delay time from the signal a, the transfer paper starts rotating at a constant speed and moves forward along the paper feed guide 33.

When the gripper 20 passes the cam 28a, the gripper
20 interrupts the photointerrupter 27b while opening. When the photointerrupter 27b generates a signal,
The pair of paper feed registers 38 rotate at double speed for a certain period of time. As a result, the transfer paper is inserted into the opened gripper 20. Since the gripper 20 closes after passing the cam 28L, the tip of the transfer paper pattern is gripped by the gripper 20.

Thereafter, the pair of paper feed registers 38 is returned to constant speed rotation to prevent the transfer paper from forming a loop between the jig gripper 20 and the pair of paper feed registers 38.

When the gripper 20 interrupts the photointerrupter 262L, the laser starts transmitting a signal to the photosensitive drum 7a. A desired yellow visible image is formed on the photosensitive drum 7a by a well-known show-through process or the like. The transfer paper conveyed by the gripper 2o has an engaging part supported by an insulated wire or the like (not shown), and passes over the transfer charger 25+a to transfer the yellow visible image.

Thereafter, each color of magenta, cyan, and plaque is transferred onto the transfer paper in the same manner.

After the gripper 2Q passes over the transfer charger 25cl,
The transfer paper is opened by the cam 2Bb and guided onto the separation claw 29. The transfer paper is further fused and fixed with a visible image by a fixing device 38, and is then discharged to the outside.

The gripper 20 stops at a predetermined position and the printing sea fence ends.

Figure 2 is a sectional view taken along the line A-A in Figure 1.
20 is shown passing between the photosensitive drum 6b and the transfer charger 25b.

In FIG. 2, after the main body (Il analysis 4), in the pantograph mechanisms 14a and 14b, the transport unit side plate 16
, 16b are supported, and the transfer unit side plates 22, 22b are further supported by a pantograph mechanism 23&, 23b provided on the transfer unit side plate.

The transfer charger guide rail 24b is connected to the transfer unit side plate 22.
, 22b, and guides the transfer charger 25b, and at the same time, the photosensitive drum 6b is fixed to the plate springs 42a, 42b.
It is elastically pressed in the direction of .

The transfer charger 25b pressed by the plate springs 42a, 42b is positioned with good reproducibility by the enons 43&, 43b provided on the side plates 16, 16b of the transport unit.

The regulation rail that regulates 19 chains is the rear lower rail /l'
44, rear upper rail 45, front lower rail /l/46, front upper rail 47, angle material tag 48.
4! '), 50.51 by the transport unit side plate 16.
15b.

In addition, regulation rails A/44, 45, 46, 47 (made of self-lubricating plastic (product name Delson, nylon, Teflon, etc.)), roller surfaces of conveyor chains 52, 53 (in the case of bush chains) It also holds down the link surfaces of the chains 52 and 53, thereby suppressing meandering, rolling (lateral shaking), etc. of the gripper 20.

The transfer belt plate 25b is stretched between a front block 54, a shield plate 55, a charging guide rail sliding member 56, and a rear block 57.

Further, a power supply connector 59 for supplying high voltage current to the transfer charger 25+ is fixed to the rear side plate 4 of the main body.

FIG. 3 is a plan view of the gripper 20 when viewed from above. FIG. 4 is a sectional view taken along the line BB in FIG. 3. Gripper support member 60-piece chain 52, 53 link 52°.
53. It is fixed to bent portions 61 and 62 provided in the. The gripper pawl 63 of the gripper 20 is rotatably supported by a shaft 64, and is biased with a gripping force by a spring 65.

Also, on the back side, there is a cam 66 for opening the gripper claw 63.
is provided.

In the embodiments of the present invention, a laser and a scanner were used as exposure means, but other methods such as CRT,
Other methods may also be used, such as those that use a direct projection edge from raw sake.

As explained above, according to the configuration of the present invention, even when multiple images are formed on a sheet, for example, the image formation is performed without staining the sheet, and the multiple images are stable without causing any misalignment. This can be done reliably.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment to which the present invention is applied, FIG. 2 is a sectional view taken along the line A-A in FIG. 1, FIG. 3 is a plan view showing a part of the sheet gripper, and FIG. FIG. 4 is a sectional view taken along the line B-B in FIG. 3; In the figure, 19 is a chain, 20 is a gripper 144
・46 is the lower rail, 45.47 is the upper rail, 52.53
is a chain. Applicant: Canon Co., Ltd.

Claims (2)

[Claims] (1) In a sheet conveying device that conveys a sheet to pass through the RA forging processing section of a plurality of image forming means and perform multiple image processing on the sheet one after another, the sheet being conveyed. What is claimed is: 1. A sheet conveying device having a gripper, wherein a sheet is gripped by a gripper and conveyed through an image processing section one after another. (2) Claim f characterized in that the gripper is moved eastward by a regulation rail.
The sheet conveyance device according to item 1 of BJ.