JPH02201366A - Image forming device - Google Patents

Abstract

PURPOSE:To fix the terminal position of the visible picture of a developing medium, and to obtain a satisfactory picture by altering the releasing timing of pressurizing members according to a carrying speed of a microcapsule sheet. CONSTITUTION:A CPU 55 controls a motor 52 in relation to a carrying speed of the microcapsule sheet 37, and rotates a capsule sheet feeding roller. In this case, the CPU 55 always judges whether the counter of the encoder of the motor 52 has reached a set value or not; when it has reached the set value, a driving source 53 is driven to release the nip of the pressurizing members 21 and 31. At this time, since the set value is corrected according to a carrying speed of the capsule sheet 37, that is, the nip is released at early timing when a carrying speed is fast, and at timing later than the former when the speed is slow, therefore the terminal value of the visible line on the developing sheet 38 is fixed; and thus, a satisfactory picture can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application 1] The present invention relates to an image forming apparatus such as a copying machine, and more particularly to a photosensitive pressure sensitive recording medium (photosensitive pressure sensitive recording medium) on which a latent optical image based on image information is formed. This is a type of image forming apparatus that forms a visible image on the surface of the color development medium by overlapping and pressure development of a color development medium (color development paper) and a color development medium (color development paper).

[Shubei Fujutsu 1] Conventionally, as an example of this type of image forming apparatus, a roll of photosensitive microcapsule paper is pulled out and a latent image corresponding to the original image is formed on the surface by exposure, and then the exposed surface is There is known a structure in which a visible image is realized on the surface of a color developing medium by stacking cut paper-like color developing paper on top of each other and applying pressure with a pressure developing means consisting of a pair of pressure rollers.

The pressure roller of this pressure developing means is opened and closed by, for example, detecting that the developing paper has passed a predetermined position on the upstream side of the pressure roller, pinching the pressure roller, and then applying pressure. It was constructed like a bolt when the roller rotated a predetermined amount.

[The problem to be solved by the invention I8! ] However, in those equipped with a function of increasing/decreasing the exposure amount of the microcapsule paper surface or enlarging/reducing the image by copying magnification, it is generally done to change the conveyance speed of the microcapsule paper. In this case, although the conveyance speed of the developer paper is synchronized with that of the microcapsule paper, the release timing of the pressure roller is not changed. There has been an inconvenience that the end position of the visible image changes depending on the conveyance speed of the microcapsule paper.

The present invention has been made in order to solve the above-mentioned problems, and an object of the present invention is to provide an image forming apparatus that can obtain high-quality images by optimizing the timing of opening of pressure members such as the pressure roller 2. The purpose is

[Means for Solving the Problems] In order to achieve the above object, an image forming apparatus of the present invention includes a conveying means for a photosensitive pressure sensitive recording medium on which a photosensitive latent image is formed based on image information, and a conveying means for the photosensitive pressure sensitive recording medium. A conveyance means for a color developing medium, in which a latent image on the surface of the light and pressure sensitive recording medium is realized as a visible image by overlapping the medium and applying pressure, and a state in which the light and pressure sensitive recording medium and the color developing medium are superimposed. In order to develop under pressure,
a pressure developing means in which a pair of pressure members are arranged facing each other so as to be openable and closable; an opening/closing control means for controlling opening/closing of the pressure member of the pressure developing means; and opening/closing of the pressure member of the opening/closing control means. and a timing control means for changing the timing according to the conveyance speed of the photosensitive pressure-sensitive recording medium of the conveying means. The medium is pressed and developed by a closed pressing member in a state in which the medium is overlapped with the color developing medium. The opening timing of the pressure member is changed depending on the conveyance speed of the pressure-sensitive recording medium, so that the end position of the visible image of the color developing medium is always approximately constant, and a high-quality image can be obtained.

[Example 1] Hereinafter, an example will be given to explain the present invention more specifically.

FIG. 2 is a schematic sectional view of a photosensitive and pressure sensitive copying machine that is capable of full color copying. Incidentally, photosensitive paper (consisting of microcapsule paper and color developer paper) that enables such copying has been proposed in Japanese Patent Application Laid-open No. 88739/1983, etc.
It will not be detailed here.

As shown in the figure, the photosensitive and pressure-sensitive copying machine 40 is composed of an original platen plus 2 and an original platen cover 1, the top plate of which is movable in the left and right directions, and a desired original is placed face down on the original platen glass 2. placed in a state. Further, at the bottom of the document table plus 2, there is a halogen lamp 3 extending in a direction perpendicular to the direction of movement of the document table plus 2, and a semi-cylindrical reflecting mirror 4 disposed so as to surround the halogen lamp 3.
In order to utilize the light emitted from the light source consisting of
A rectifier 5 is arranged. Further, on the right side of the halogen lamp 3, a seven-hole 6 and a louver 7 for introducing air from the outside are provided, so that air can be efficiently applied to the document table glass 2. Light emitted from the halogen lamp 3 and reflected from the document whose document table is positioned on the lath 2 passes through the filter 8 and enters the lens 9 . The filter 8 is used to change the transmission characteristics according to the sensitivity characteristics of the microcapsule paper 37 and adjust the tone of the copied image. The lens X:9 is attached to the lens mounting plate 10, and is placed at a small angle
! Adjustment is possible. Furthermore, the lens 9 is movable in the vertical direction so that the copying magnification can be changed, and is raised and lowered by the action of a lens raising and lowering device 51 shown in FIG. The light focused by the lens 9 is reflected by two reflecting mirrors 11 and 11 at 180
The direction is changed and an image is formed on the microcapsule paper 37 which is in contact with the lower part of the exposure table 19. Double reflective mirror 11゜1
1 is fixed to a mirror mounting plate 12, and the optical path length and focus are adjusted by fine adjustment of the mirror mounting plate 12.

On the other hand, a roll of microcapsule paper 37 is wound around a cartridge shaft 14 and housed in a removable cartridge 13 disposed below the document table glass 2.
One end thereof is guided by a feed roller 15 and an idle roller 17, passes below the exposure table 19, and then passes through a pressure developing device 2.
0, and then guided to a peeling roller 23 and a meandering adjustment roller 24, and wound up onto a winding pongee 25. The unexposed microcapsule paper 37 after leaving the cartridge 13 is maintained in an unexposed state by the light shielding cover 16.

The conveyance speed of the microcapsule paper 37 is controlled by the capsule paper feed roller 22 connected to the motor 52 shown in FIG. 1, and changes in relation to the moving speed of the document table glass 2 and the magnification.

Therefore, latent images of predetermined lines of the original are sequentially formed on the microcapsule paper 37 as it passes through the exposure table 19.

On the other hand, a developer paper cassette 32 containing cut paper type developer paper 38 is provided below the pressure developing device 20. The developer paper 38 is taken out one by one by a half-moon roller 33, and then transferred to the developer paper roller 34 and the resist. After the leading end is aligned by the date 35, the paper is transported to the paper inlet of the pressure developing device 20.

Therefore, the pressure developing device 20 includes the microcapsule paper 37.
The color developer paper 38 and the color developer paper 38 are supplied in a state where they are in close contact with each other and are integrated. The pressure developing device 20 is composed of a first pressure roller 21 and a second pressure roller 31. Microcapsule paper 37
The microcapsule surface on which the latent image of is formed and the developer-coated surface of the color developer paper 38 are in contact with each other on the inside, and are sandwiched between the first pressure roller 21 and the second pressure roller 231 as one body. Pressure is applied. This pressure destroys the unexposed microcapsules and forms an image on the developer paper 38.

The microcapsule paper 37 and the color developer paper 38 that have come out of the pressure developing device are conveyed by the capsule paper feed roller 22, and the microcapsule paper is moved upward by the peeling roller 23, and the color developer paper 3 is transported by the peeling roller 23.
8 are orthogonally separated.

After color development is promoted by the heat fixing device and an image is formed on the color developer paper 38, the paper is conveyed to the paper discharge tray 27 with the image side facing up. The heat fixing device is composed of a hollow heat roller 29 having a heater 30 inside and a color developing paper feed roller 28.

Figure fjS3 shows a sectional view of the pressure developing device. A first pressure roller 21 and a @2 pressure roller 31 opposite thereto are arranged, and a microcapsule paper 37 is placed between them.
and color developer paper 38 are overlapped and passed through. The first pressure roller 21 is! It is movably attached to the 17th frame 42 together with the @1 backup roller 41. The second pressure roller 31 is attached to the twenty-seventh frame 44 together with the second backup roller 43. @27
The frame 44 has a structure that allows the frame itself to move relative to the IJ417 frame 42, and its mechanism is as follows.
When the camshaft 46 having an eccentric cam shape that comes into contact with the Laemmli 7 troller 45 is driven by the drive shown in FIG. 27th frame 44 @17
moves toward the frame 42 side, and along with this, the second pressure roller 3
1 also moves. At this time, since the first pressure roller 21 is pressed by the pressure spring 47 via the first back-up roller 41, the first pressure roller 21 and the second pressure roller 31 are pressed by the pressure force of the pressure spring 47. It becomes pressure-welded.

Furthermore, when the valley portion of the cam reaches the contact position with the seventh frame 7 troller 45, the 27th frame 44 is connected to the 17th frame 4.
1, the pressure contact state between the first pressure roller 21 and the second pressure roller 31 is released, and a gap is created between the pressure rollers for feeding the color developing sheet 38.

Next, a driving source 5 that rotates the pressure developing camshaft 46
3 and its control device 50 will be explained with reference to FIG.

The drive source 53 is connected to a central processing unit (hereinafter referred to as CPU) 55 via an interface circuit 54. Sensors 56 and 59 are further connected to this interface circuit 54. This sensor 56 is arranged upstream of the 10th line 21 and the 20th line 31, and is located at the time when the leading edge of the color developer paper 38 passes through the sensor 56 and at the time when the rear end of the color developer paper 38 passes through the sensor 56. Detect pickpockets. Further, the sensor 59 measures the amount of light from the halogen lamp 3. Furthermore, the lens lifting device 51 and the motor 52 are connected to the interface H path 54. The CPU 55 controls the lens lifting device RA 51 and the motor 52 to achieve exposure at a desired magnification. The CPU 55 also includes a random access memory 57 as a work area for the CPU 55, and a
Read-only memory 58 that describes the processing procedure of U55
are connected.

The opening/closing timing of the first pressure roller 21 and the second pressure roller 31 of the pressure developing device fi20 configured as above will be explained below.

When the exposure is completed, the microcapsule paper 37 and the color developer paper 38 are overlapped and conveyed. This conveyance speed is determined by the CPU 55 in relation to the magnification determined by the position of the lens 9, the amount of light from the halogen lamp 3, and the like. Then, the CPU 55 controls the motor 52 in relation to the determined transport speed to rotate the capsule paper feed roller 22.

The color developer paper 38 is not affected by the rotational speed of the capsule paper feed roller 22, and is fed into the pressure developing device 20 exclusively at a constant speed. At this time, when the leading edge of the color developing paper 38 is detected by the sensor 56, the detection signal is sent to the CPU 55, and the leading edge of the color developing paper 38 is moved to both pressure members 21 of the pressure developing device 20 by the operation of a known delay timer. It is stopped when it is fed a little between .3i and 3i.

On the other hand, the ROM 58 of the control device 50 stores the transport path distance from the exposure start position of the surface of the microcapsule paper 37 to the leading edge of the color developing medium 38 in the pressure developing device 20 and the transport of the microcapsule paper 37 according to each copying magnification. The opening timing of the pressure developing device 20 corresponding to the speed is stored in advance, and the counters of the motor 52 (both well known) are cleared at the same time as the exposure starts, and the opening timing of the pressure developing device 20 corresponding to the exposure speed is cleared. When the set count value is reached, the opening/closing driving source 53 between the surface pressing members 21 and 31 of the pressure developing device 20 is driven to nip the facing pressure members 21 and 31. This nip timing is the point at which the starting end of the dew tip of the top microcapsule paper 37 coincides with the leading edge of the color developing paper 38.

As the pressure-receiving member 21.31 rotates, a visible image is developed on the developer paper 38.

During this time, the CPU 55 constantly judges whether the cutter of the encoder of the motor 52 has reached the set value based on the chart 70 in FIG. Open the nip of the pressure member 21.31. At this time, since the set value is corrected according to the conveyance speed of the microcapsule paper 37, that is, when the conveyance speed is fast, the nip is opened at an early timing, and when it is slow, the nip is opened at a later timing. Developing paper 38
The terminal value of the upper visible image is constant, which is good.

[Effects of the Invention] As detailed above, in the present invention, the opening timing of the pressure member is changed depending on the conveyance speed of the photosensitive and pressure sensitive recording medium, so that the end position of the visible image of the color developing medium is kept constant. can provide high-quality images.

[Brief explanation of the drawing]

1 to Pt53 show an embodiment of the present invention. FIG. 1 is a diagram showing the configuration of a control device that controls pressure development in the image forming apparatus of the embodiment, and FIG. FIG. 3 is a diagram illustrating the details of the pressure developing device, and FIG. 4 is a control 70-chart of the opening timing in the pressure developing device. In the figure, 21 and 31 are first and m2 pressure rollers corresponding to the pressure means, 22 is a microcapsule paper feed roller corresponding to the conveyance means, and 53 is a drive source corresponding to the opening/closing means. Patent Applicant: Brother Industries, Ltd. President Katsuji Kawanari Figure 20

Claims (1)

[Scope of Claims] 1. A means for transporting a photosensitive pressure sensitive recording medium on which a latent photoimage based on image information is formed; A means for conveying a color developing medium in which a latent optical image is realized as a visible image, and a pair of pressure members that can be opened and closed in order to pressurize and develop the light and pressure sensitive recording medium and the color developing medium in a superimposed state. pressure developing means disposed opposite to each other; opening/closing control means for controlling opening/closing of the pressure member of the pressure developing means; and a photosensitive pressure sensitive pressure of the conveying means to control the opening timing of the pressure member of the opening/closing control means. An image forming apparatus comprising: a timing control means for changing the timing according to the conveyance speed of a recording medium.