JPH04178673A - Transferring device - Google Patents

Abstract

PURPOSE:To always make the surface potential of a transferring paper an optimum potential according to wet and dry states so that transferring efficiency is stabilized by providing a multiple structure mash-state grid on a certain main surface and making it relatively movable with respect to other grid, and changing corona discharging. CONSTITUTION:The transferring device is constituted of a case main body 10 whose upper surface is opened, holders 11 and 12, a high voltage wire 14, a fixed grid 15 covering an upper surface open part, and a movable grid 16 which is superposed and disposed on the upper surface of the grid 15 in such a way that it can slide. And when the partitioning part 18 of both grids 15 and 16 meet each other, the mesh is fully opened; and when the grid 16 slides on the grid 15, the opening of both meshes are reduced to 1/2. That is, the transferring paper is electrostatically charged through the grids 15 and 16 by the corona discharging from the wire 14, and the developed image of a photosensitive drum 3 is transferred to the paper 6 by this electrostatic charging. At this time, the grid 16 slides to change the size of the mesh in order to obtain the corona discharging which is the optimum electrostatic charging state for the wet and dry states of the paper 6.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transfer device, in particular, a case in which one main surface is open, a wire is stretched between holders at both ends, and a grid is provided on the one main surface. This invention relates to a transfer device in a copying machine.

Traditionally, this type of transfer device has been designed to improve transfer efficiency by leaving the entire surface of the transfer device case open, and fixedly providing a mesh-like grid on the open surface that partitions this open area at equal intervals. I was trying to stabilize it.

However, the grid used in the conventional transfer device is
Since the size of the meshes partitioned at equal intervals is always constant, in the case of transfer paper with humidity conditions suitable for the amount of corona discharge performed through the size of the meshes, it is possible to stabilize the transfer efficiency. Although it is possible to obtain
For example, when the humidity of the transfer paper changes due to atmospheric temperature differences due to seasonal changes, the chargeability of the transfer paper due to corona discharge from the wire fluctuates, resulting in unstable transfer efficiency. was there.

The present invention was invented in view of the above-mentioned problems, and its purpose is to uniformly charge the transfer paper with the corona discharge from the wire even if the humidity of the transfer paper fluctuates due to changes in atmospheric temperature, etc. The present invention provides a transfer device for a copying machine that can improve transfer efficiency.

In order to achieve the objective, the present invention provides a transfer device in which a wire is stretched between holders at both ends of a case with one main surface open.
providing a mesh-like grid with a multiple structure on the one main surface;
The present invention is characterized in that at least one of the grids is movable relative to the other grids.

With the above configuration, at least one grid can be slid and the size of the mesh can be changed, so the corona discharge from the wire can be varied, and the corona can be adjusted to suit the dry and wet conditions of the transfer paper. It can be adjusted so that the discharge occurs.

Large - one gong, one go The transfer device of the present invention will be explained based on the embodiments shown in the drawings.

FIG. 5 is a front view schematically showing the internal structure of the image forming apparatus A. In the image forming apparatus A, a series of image forming processes including exposure, development, etc. are performed.

That is, the light emitted from the exposure section 1 is irradiated onto the photoreceptor drum 3, which has been charged in advance by the charger 2.
Electrostatic latent image formation is performed. Then, the toner supplied from the developing device 4 adheres to the electrostatic latent image on the photosensitive drum 3 and development is performed, and then the toner image on the photosensitive drum 3 is transferred to the paper 6 by the transfer device 5. A transfer process is performed. In this transfer process, the residual toner that has not been transferred to the paper 6 is scraped off by the blade of the cleaning box 7, thereby cleaning the photosensitive drum 3. On the other hand, when the paper 6 that has been transported through the paper transport path 8 and has undergone the transfer passes through the fixing device 9, the fixing process is performed.

By the way, the transfer device 5 includes a case body 10 formed of a metal plate having a length direction parallel to the axial direction of the photoreceptor drum 3 and having a generally rectangular box shape with an open top surface; Holder 11.1 fixed to both lengthwise ends of
2, a high-voltage wire 14 having one end fixed to the holder 11 and the other end fixed to the holder 12 via a spring 13; a fixing grid 15 covering the open upper surface of the main body 10; A movable grid 16 that is slidably arranged in an overlapping manner on the upper surface, and both grids 1
5.16 and a support member 17.17 that supports these grids 15.16 while maintaining an insulated state with the main body 10.
The fixing grid 15 is attached to the edge of the open upper surface portion of the fixing grid 10, and the fixing grid 15 is fixed to the main body 10 via the supporting members 17.17. On the other hand, the movable grid 16 is
The upper surface of the fixed grid 15 is slidably supported by the support member 17.17.

As shown in FIG. 3, the mesh of the movable grid 16 has a shape in which the open area of the main body 10 is partitioned into an arbitrary number of parts at equal intervals, while the mesh of the fixed grid 15 has a shape that divides the open area of the main body 10 into an arbitrary number of sections, as shown in FIG. 16, and when the partitions 18 of both the grids 15 and 16 coincide with each other, the meshes of both the grids 15 and 16 are fully opened as shown in FIG. When it is slid against the fixed grid 15, the mutual meshes are reduced to 172 as in the fourth case.

Next, the operation of the transfer device constructed as described above will be explained.

That is, due to the corona discharge from the wire 14, the grid 1
5.16, the transfer paper 6 is charged, and the developed image on the photosensitive drum 3 is transferred to the transfer paper 6 by this charge. At this time, the movable grid 16 is slid relative to the fixed grid 15 to change the size of the mesh in order to generate a corona discharge that causes the transfer paper 6 to be charged in a wet and dry state.

For example, when the atmospheric temperature is high and the humidity of the transfer paper 6 is high, such as in the summer, the grid 16 is slid so that the size of the mensch becomes coarse, and the corona discharge from the wire is increased so that the transfer paper On the other hand, when the atmospheric temperature is low and the transfer paper 6 is dry, such as during winter, the method described in step 1. By reducing the size of the transfer paper 6 to suppress corona discharge to some extent and reducing the amount of charge on the transfer paper 6, the transfer paper 6 can be
The amount of charge on the transfer paper 6 can be made uniform, and the optimum potential can be maintained at all times, thereby improving stabilization of transfer efficiency.

In this embodiment, the slide of the movable grid 16 is manually operated. Accordingly, the movable grid 16 may be mechanically operated, and in any case, the means for sliding the movable grid 16 is not particularly limited.

The present invention slides the grid to change the corona discharge, so that even if the dry/wet state of the transfer paper changes due to changes in atmospheric humidity, for example, it will not be affected by the dry/wet state of the transfer paper. The surface potential of the transfer paper can always be kept at the optimum potential without any interference, and as a result, stabilization of transfer efficiency can be significantly improved.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a transfer device according to the present invention. Second
The figure is a sectional view taken along line XX in FIG. FIG. 3 is a plan view of the movable grid. FIG. 4 is an explanatory diagram showing the movable grid sliding with respect to the fixed grid. FIG. 5 is a schematic front view of an image forming apparatus equipped with the present invention. 10...Case body, 11...Holder, 12...
・Holder, 14...Wire, 15...Grid (
fixed), 16...grid (movable). Patent applicant: Murata Machinery Co., Ltd. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] (1) In a transfer device in which a wire is installed between holders at both ends of a case with one main surface open, a mesh-like grid with a multilayer structure is provided on one main surface of the case, and at least one of the grids is connected to another grid. A transfer device characterized in that it is movable relative to the transfer device.