JPS6052864A - Device for guiding conveyance of sheet - Google Patents

Abstract

PURPOSE:To enable stable conveyance without curling up with a small-sized device in the case of separating a sheet from a photosensitive body by a separating means provided on one side by having a guide member which inclines downward toward the axial direction of the photosensitive body from the sepn. side. CONSTITUTION:Transfer paper P stripped from a photosensitive drum 4 by a separating belt 9 is supported between a separating roller 8 and a paired separating roller or conveying roller gear 2 and paired conveying roller 3 and is delivered to an inlet guide plate of a fixing device along a device 1' for guiding conveyance. The device 1' is provided with a step across the direction where the paper P travels so as to descend from the sepn. side thereof toward the inner side and therefore the effect of bringing the transfer paper on the inner side toward the device 1' is created by the difference in positional energy, etc. and the transfer paper is conveyed in proximity to the device 1', by which curling up of the paper P is decreased.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to sheet conveyance in copying machines, printing machines, recording machines, and other various machines (hereinafter simply referred to as copying machines) equipped with mechanisms for conveying sheets (including so-called transfer paper, etc.). This invention relates to a guide device.

Conventionally, this type of device has been used for
In order to avoid 1j'4 and 5 bending during paper feeding, the distance from the dividing device to the fixing device is long and a reliable conveyance method such as a belt is used.

However, considering the miniaturization of copying machine bodies, it is now inevitable to reduce this space, and it is obvious that the above-mentioned effects will occur if the conventional edge feeding device is simply shortened. It is.

Therefore, in order to lengthen the conveyance distance and reduce space, a curved conveyance path is required in order to change the transfer paper conveyance from a straight line to a meandering one.

However, in a conveying device having such a configuration, the conveying state is extremely unstable compared to a linear one, and there are disadvantages such as scratches on the surface of the soft photosensitive drum due to the rear edge of the transfer paper lifting up. there were.

Therefore, an object of the present invention is to provide a novel sheet conveyance guide device that is improved in view of these drawbacks.

That is, it prevents various effects caused by the lifting of the trailing edge of the transfer paper caused by the above-mentioned instability of the transfer paper conveyance state, such as the generation of black spots due to dusting on the soft photosensitive drum, the scattering of the transfer paper image, etc., and also prevents the transfer paper from being It is also possible to achieve the effect of stabilizing the entry of the particles into the fixing device. This means that the M'S force caused by curling of the transfer paper on the back side (separation side) was reduced, and the occurrence of wrinkles was also reduced.

The main structure of the present invention, which achieves the above object, is that in a copying machine that separates and conveys a sheet from above a photoreceptor by a separating means provided on one side, the sheet is separated from the separating side provided with the separating means. This sheet conveyance guide device includes a sheet conveyance guide member that is inclined downward in the axial direction of the photoreceptor.

Hereinafter, specific embodiments of the present invention will be described in detail with reference to the drawings. Figure 1 shows a conventional sheet conveyance guide in which the transfer paper conveyance path is curved so that even if the space from the separation device to the fixing device is reduced to reduce the size, the shock when the transfer paper enters the fixing device can be reduced. FIG. 2 is a perspective view showing an example of the device; FIG. 2 is a perspective view showing an embodiment of the present invention; the structure of the device is an improved version of the sheet conveyance guide device shown in FIG. 1 (partially omitted);
shows. 1 is a conventional conveyance guide device, i' is an improved conveyance guide device of the present invention, 2 is a drive device for conveying the transfer paper together with the conveyance roller, 3 is the conveyance roller, and 4 is a photosensitive device forming a latent image. 5 is a fixing device entrance guide plate for guiding the transfer paper from the conveyance guide device to the fixing device; 6, 7;
8. a fixing device driven and driving roller for fixing the toner image formed on the transfer paper;・9 indicates a separation roller and a separation belt for separating the transfer paper from the photosensitive drum.

The transfer paper P separated from the photosensitive drum 4 by the separation belt 9 is supported between the separation roller 8 and a pair of separation rollers (not shown) or between the conveyance roller gear 2 and the pair of conveyance rollers 3.
The toner image on the transfer paper P is fed to the fixing device entrance guide plate 5 along the conveyance guide device 1 (1')K, and guided between the fixing device driven and driving rollers 6 and 7. It will be done.

As shown in FIG. 1, since the transfer paper P is supported on one side, the back side, where no external force is applied, is difficult to separate and flies up. This condition also occurs at the trailing edge of the transfer paper P, and the bounce-up is especially noticeable in the case of a soft photoreceptor drum.
It is the main cause of sunspot occurrence. This splashing also leads to scattering of unfixed images. As shown in FIG. 2, in the case of the conveyance guide device according to the present invention, the conveyance guide device it 1
A simple structure in which a step is created in the paper passing width direction of the transfer paper P so that the paper descends from the separation side toward the back side (toward the axis of the photoreceptor) reduces this bounce-up of the transfer paper P. It is possible to do so. This is the transport guide device i
! The effect of moving the actual transfer paper closer to the conveyance guide device 1' due to the difference in positional energy caused by setting the front separation side vertex of t, 1 closer to the separation point and providing a step between the separation side and the back side. The guide device 1 conveys the transfer paper.
By transporting the transfer paper close to , it is possible to reduce the lifting of the transfer paper P.

Another effect is that the back side of the transfer paper P does not advance to the fixing device earlier than the separation side, and the transfer paper P enters the fixing device as specified, which stabilizes the conveyance of the transfer paper. It turned out to be a useful result.

As explained above, according to the configuration of the present invention, the positional difference (height direction and sheet feeding direction) of the sheet to be conveyed is reduced between the separation side and the back side, and the sheet can be conveyed in a small size and in good condition. be.

[Brief explanation of the drawing]

FIG. 11 is a perspective view showing a conventional sheet conveyance guide device;
Figure 2 shows the sheet conveyance guide of the present invention: &! FIG. In the figure, 1' is a conveyance guide device, 3 is a conveyance roller, 9
is a separation belt.

Claims (1)

[Scope of Claims] In a copying machine that separates and conveys a sheet from above a photoconductor by a separating means provided on one side, a sheet is separated from the top of the photoconductor and transported downward in the axial direction of the photoconductor from the separating side where the separating device is provided. A sheet conveyance guide device having a sheet conveyance guide member that is inclined toward the side.