JPH03120547A - Image forming device - Google Patents

Abstract

PURPOSE:To eliminate wrinkles of developing paper and dislocation of a devel oped part and to stabilize pressure development by providing plural pressure developing devices composed of pressure rollers having roller width of the developing paper. CONSTITUTION:When a microcapsule paper 11 is exposed by an exposing device 15 and a developing paper 21 in size A3 for instance is fed from a cassette 29, the exposure part of the paper 11 and the paper 21 are pressed between the pressure rollers 22a and 22b of a first pressure developing device 20. After an image is formed on the paper 21, the paper 21 is fed to a heat fixing device passing through between the released rollers 32a and 32b of a second pressure developing device 30. When a developing paper 31 in size A4 for instance is fed from the cassette 39, it passes through the released rollers 22a and 22b of the device 20, is pressured between the rollers 32a and 32b of the device 30 and is heat-fixed by the heat fixing device.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image forming apparatus, and particularly to an image forming apparatus capable of stable pressure development even if the width of the transfer member is different.

[Conventional technology]

2. Description of the Related Art Conventionally, image forming apparatuses have been used that overlap an exposed photosensitive member and a transfer member to form an image on the transfer member.

In general, such an image forming apparatus overlaps a photosensitive member such as microcapsule paper that has been exposed to light based on an original and a transfer member such as color developer paper that forms an image, and uses two opposing pressure rollers in a pressure developing device. By applying pressure between the transfer members, the transfer material of the photosensitive member is transferred to the transfer member, and an image is formed on the transfer member.

[Problem to be solved by the invention]

However, in conventional image forming apparatuses, transfer members of different sizes are subjected to pressure development using a single pressure development device, so there is a problem in that stable pressure development cannot be performed when transfer members of different sizes are used.

For example, when pressure developing an A4 size (width 210m) transfer member and a letter size (width 216cm) transfer member,
Unless the pressure setting of the pressure developing device is changed, there are problems such as wrinkles occurring in the transfer member due to a difference in the width of each side, or the developing portion of the transfer member being misaligned.

In conventional image forming apparatuses, when forming images on transfer members of different sizes using a single pressure development device, the pressure setting of the pressure roller of the pressure development device must be changed each time the size of the transfer member changes. However, there are problems in that the work is complicated and takes a long time, and the mechanism of the pressure roller becomes complicated, resulting in an increase in cost.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an image forming apparatus equipped with a plurality of pressure developing devices that can perform stable pressure development even if the width of the transfer member is different. do.

[Means to solve the problem]

In order to achieve this object, the image forming apparatus of the present invention pressure-develops an image on the transfer member by overlapping a photosensitive member exposed based on an original and a transfer member and applying pressure between pressure rollers. In an image forming apparatus equipped with a pressure developing device, the image forming device includes a plurality of pressure developing devices each having a pressure roller having a roller width corresponding to the width of the transfer member and having a pressure set in advance. The structure was designed to be prepared.

[Effect]

According to the image forming apparatus of the present invention having the above configuration, a plurality of pressure developing devices are provided, and each pressure roller provided in each pressure developing device has a roller width corresponding to the width of the transfer member. Transfer members of various sizes are pressure developed by a pressure developing device having an optimal pressure roller width among the plurality of pressure developing devices mentioned above, which are adjusted in advance to match the width of the transfer member. Stable pressure development is performed without wrinkles on the transfer member or displacement of the developed portion of the transfer member.

〔Example〕

An embodiment embodying the present invention will be described below with reference to the drawings.

FIG. 1 shows an image forming apparatus according to the present invention. This image forming apparatus 10 conveys a strip of continuous microcapsule paper 11 as a photosensitive member in the direction of the arrow in the drawing, so the microcapsule paper 11 is wound. delivery roller 12
and a winding roller 1 that winds up the microcapsule paper 11.
3 and guide rollers 14 and 14 for guiding the microcapsule paper 11 being conveyed.

An exposure device 15 is provided downstream of the delivery roller 12 in the transport direction of the microcapsule paper 11, and in this exposure device 15, the microcapsule paper 11 is exposed to light based on a document.

Further downstream in the conveyance direction of the microcapsule paper 11 of the exposure device 15, the exposed microcapsule paper 11 and a color developer paper as a transfer member for forming an image are superimposed,
A first pressure developing device 20 and a second pressure developing device 30 are provided for pressure developing an image on developer paper.

The first pressure developing device 20 pressure develops a wide color developing paper 21 such as A3 size, and the second pressure developing device 30 performs pressure developing on a wide color developing paper 21 such as A3 size.
A color developing paper 31 having a relatively narrow width is subjected to pressure development.

As shown in FIGS. 1 and 2(a), the first pressure developing device 20 includes a first pressure roller 22a for superimposing and pressing the microcapsule paper 11 and the wide color developer paper 21; 22b are provided facing each other. The first pressure roller 22a is connected to the cam floor 24 via a first back-up roller 23. This cam floor 2
4 is connected to a cam 25, and when the cam 25 rotates, the first pressure rollers 22a and 22b are opened and closed. In addition, the first pressure roller 2
2b is biased toward the first pressure roller 22a by a second back-up roller 26, and the second back-up roller 26 is biased by a biasing means 27 such as a spring for biasing the first pressure roller 22b. The biasing force of the biasing means 27 can be adjusted using a screw 28.

The second pressure developing device 30 is equipped with second pressure rollers 32a and 32b that overlap and press the exposed microcapsule paper 11 and color developer paper 31. As shown in FIG. 2(b), the second pressure rollers 32a, 32b have a width slightly larger than the width of the color developing paper 31, and have tapered diameters at both ends. Small diameter part 33a
, 33b are formed so that the microcapsule paper 11 does not stain the second pressure rollers 32a, 32b. Note that the components in the second pressure developing device 30 that are denoted by the same reference numerals as those in the first pressure developing device 20 are the same as those in the first pressure developing device 20, and therefore a description thereof will be omitted.

Further, the image forming apparatus according to the present invention is provided with a heat fixing device (not shown) for heat fixing the image pressure-developed onto the developer paper by the first pressure developing device 20 and the second pressure developing device 30. ing.

The operation of the image forming apparatus according to the present invention will be described below, taking as an example the case where images are formed on A3 size color developer paper 21 and A4 size color developer paper 31.

Here, the A3 size color developing paper 21 is stored in the first pressure developing device 2.
0, and the A4 size color developing paper 31 is subjected to pressure development by the second pressure developing device 30.

First, a case will be described in which an image is formed on A3 size developing paper 21.

The A3 size developer paper 21 is ejected from the paper feed cassette 29 by a paper feeder (not shown), and the developer paper transport roller (
(not shown), the developing paper is conveyed to a position slightly beyond the center of the first pressure rollers 22a, 22b of the first pressure developing device 20, and then stopped.

On the other hand, the microcapsule paper 11 is taken up by a take-up roller 13 and transported in the direction of the arrow, and after being exposed in an exposure device 15, the tip of the exposed portion of the microcapsule paper 11 is moved to the first pressure roller 22a, 22b
is transported to the center point.

In this way, the exposed portions of the color developer paper 21 and the microcapsule paper 11 are exposed to the first pressure roller 22a of the first pressure development device 20.
, 22b, the cam 25 of the first pressure developing device 20 rotates, and the first pressure roller 22a passes through the cam floor 24.

The color developer paper 21 and the microcapsule paper 11 are pressurized between 22b, and an image is pressure developed on the color developer paper.

At this time, the cam 25 is not working in the second pressure developing device 30, and the second pressure roller 32a is not working.

32b is open.

Next, a case will be described in which an image is formed on A4 size color developing paper 31.

The A4 size developer paper 31 is ejected from the paper feed cassette 39 by a paper feeder (not shown), and the developer paper transport roller (
(not shown), the developing paper 31 is conveyed to a position slightly beyond the center of the second pressure rollers 32a, 32b of the second pressure developing device 30, and then stopped.

On the other hand, the microcapsule paper 11 is transported by being wound around a winding roller 13, and after being exposed to light in an exposure device 15, the tip of the exposed portion of the microcapsule paper 11 is at the center of the second pressure rollers 32a, 32b. transported to the point.

Note that when the color developing paper 31 is developed in the second pressure developing device 30, the cam 25 of the first pressure developing device 20 is not working, and the first pressure roller 22a is not working.

22b is open, and the developing paper 31 and the microcapsule paper 11 are connected to the first pressure roller 22a.

22b, and is conveyed to the second pressure developing device 30.

In this way, when the exposed portions of the color developer paper and the microcapsule paper 11 are overlapped in the second pressure developing device 30, the cam 25 of the second pressure developing device 30 rotates, and the cam floor 2
4, the second pressure rollers 32a and 32b press the developer paper 31 and the microcapsule paper 11. At this time, the small diameter portions 33a, 33b are formed at both ends of the second pressure rollers 32a, 32b as described above, and the width of the second pressure rollers 32a, 32b is slightly wider than the developer paper 31. Since the setting is made, the microcapsules of the microcapsule paper 11 that are not overlapped with the color developing paper are destroyed and the second pressure roller 32a is released.

There is no risk of soiling both ends of 32b.

Finally, the image pressure developed on the developer paper by the first pressure developing device 20 or the second pressure developing device 30 is conveyed to a heat fixing device (not shown), where the image is heat fixed.

Although this embodiment relates to an image forming apparatus equipped with two pressure developing devices, it is also possible to have three or more pressure developing devices depending on the type of color developing paper.

〔Effect of the invention〕

As is clear from the detailed description above, according to the present invention, when images are formed on transfer members of different sizes, pressure development is performed using a pressure development device having an optimal pressure roller width for each size, so that the transfer It is possible to prevent wrinkles from forming on the member and misalignment of the developed area of the transfer member.
The effect is that stable image formation can be performed.

It is a perspective view which shows the state which presses an ear member.

DESCRIPTION OF SYMBOLS 10... Image forming device, 11... Microcapsule paper, 15... Exposure device, 20... First pressure developing device, 21.31... Color developer paper, 22a, 22b... First
Pressure roller 30...second pressure developing device, 32a.

32b... second pressure roller

Claims (1)

[Claims] An image forming apparatus comprising a pressure developing device that pressure-develops an image on the transfer member by overlapping a photosensitive member exposed based on a document and a transfer member and applying pressure between pressure rollers, the image forming device An image forming apparatus comprising a plurality of pressure developing devices each having a pressure roller having a roller width corresponding to the width of the transfer member and having a pressure set in advance.