JP2530754B2 - Void lamp controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to an image forming apparatus that performs an image forming process using a photosensitive sheet on which a latent image is formed by exposure, in a non-image area at both ends of the photosensitive sheet. The present invention relates to a void lamp control device for exposing a substrate to prevent development.

(B) Conventional Technology Photosensitive sheet having light and pressure sensitivity (a sheet that transfers dye to an image receiving sheet in a region that is not exposed to light, but does not transfer dye to the image receiving sheet when pressure is applied to the image receiving sheet) ) Is used to perform an image forming process,
The photosensitive sheet is wound around the supply shaft, and the supply unit
The photosensitive sheet conveying system including the buffer section and the pressure developing section is used to wind the film around the winding shaft. The photosensitive sheet is exposed to image forming light such as document reflected light and laser light in the exposure section to form a latent image, and the latent image is visualized by being pressed by the pressure developing section while being superimposed on the image receiving sheet. Then, it is transferred to the image receiving sheet.

By the way, when a latent image is formed on a photosensitive sheet with image forming light, in most cases, the image width (width to which the image forming light is irradiated) becomes narrower than the width of the photosensitive sheet itself. Therefore, if the pressure developing process is performed in this state, the both end portions not exposed to light are developed, and the widthwise end portion of the image receiving sheet may be soiled. In order to prevent this stain, a void lamp is placed immediately before the exposed part, and both ends of the photosensitive sheet are exposed by turning on the void lamp during the exposure process, and the dye on both ends adheres to the image receiving sheet. I try not to.

(C) Problem to be Solved by the Invention Conventionally, however, void exposure may be insufficient at the leading edge of an image, resulting in smearing at both ends of the image receiving sheet. This is due to two causes.One is that since the void lamp is provided in front of the exposure part, if the void lamp is turned on at the same time as the exposure starts, the area between the void lamp and the exposure part is not exposed. Met. Another reason is that the amount of light at the start of lighting the void lamp is unstable, so that a sufficient amount of light is not provided and some dye is transferred.

In order to solve these problems, before starting the exposure process, the time t ₁ for exposing the area between the void lamp and the exposed portion, and the time t ₂ until the light amount of the void lamp stabilizes, It is conceivable that the void lamp is turned on by going back t ₁ + t _{2 of the} above, but this method causes the inconvenience of waste of time and the inconvenience of complicated control.

SUMMARY OF THE INVENTION An object of the present invention is to provide a void lamp control device which is capable of eliminating the shortage of void exposure with simple control without wasting time.

(D) Means for Solving the Problems By the way, in an image forming apparatus that performs an image forming process using a photosensitive sheet, if an excessive slack or a pulling force is applied to the photosensitive sheet during image formation, the formed image is not formed. Distortion may occur. Therefore, in an image forming apparatus that forms an image using a photosensitive sheet, first, the photosensitive sheet is initially set before starting the exposure process, which is the first stage of the image forming process. This is an operation in which the photosensitive sheet of the supply shaft is once pulled out to the buffer section, and then a predetermined torque is applied to pull the photosensitive sheet of the buffer section to the take-up shaft. Set. The present invention utilizes the initial setting process performed before the start of the exposure process, and is characterized in that means for starting the exposure of the void lamp during the initial setting operation is provided.

(E) Function In the present invention, the void lamp is started to be turned on during the initial setting operation in which the photosensitive sheet is pulled out and initially set before the exposure processing. Therefore, the photosensitive sheet pulled out in the initial setting operation is exposed by the void lamp, and the area corresponding to the leading edge of the image becomes the void-exposed area. Further, since the void lamp is turned on in advance, it becomes possible to perform the void exposure with a sufficient light amount.

If the time for exposing the area between the void lamp and the exposed portion is t ₁ and the time until the light quantity of the void lamp stabilizes is t ₂ , the time required for the initial setting operation is “t It is necessary to exceed ₁ + t ₂ ", but since the void lamp is located immediately before the exposed part and t ₂ is a sufficiently short time," t ₁ + t ₂ "is required for the initial setting. Shorter than time.

(F) Example FIG. 2 is a diagram showing a photosensitive sheet conveying system.

The photosensitive sheet 1 is wound around a supply shaft 2. Supply axis 2
Are housed in a cartridge (not shown) and protected from external light and external pressure. The photosensitive sheet 1 is pulled out from the supply shaft 2, and has a sprocket roller 3, a void lamp 4, an exposure table 5 forming an exposure unit, a buffer roller 6 forming a buffer unit, a pressure roller 7 forming a pressure developing unit, and a peeling unit. It is wound around the winding shaft 9 via the roller 8. The photosensitive sheet conveying system is composed of the above-mentioned supply shaft 2, sprocket roller 3, ... Winding shaft 9.

Here, the processing at the time of image formation will be briefly described. In the image forming process, the pressure developing process is performed after the exposure process is completed. This is because the photosensitivity and the pressure sensitivity of the photosensitive sheet 1 are significantly different. Therefore, by changing the conveying speed of the photosensitive sheet during the exposure process and the pressure developing process, the process corresponding to each sensitivity can be performed. It can be carried out.

The exposure process is performed by moving the buffer roller 6 in the direction of arrow A. During the exposure process, the supply shaft 2 is unlocked and the winding shaft 9 is locked. Then, the pressure roller 7 is released from the pressure, and the buffer roller 6 moves in the arrow A direction. As a result, the photosensitive sheet 1 is pulled out from the supply shaft 2, and the photosensitive sheet is stocked in the portion where the buffer roller 6 is pulled out, that is, the buffer portion. At this time, image forming light such as document reflection light or laser light is guided onto the exposure table 5, a latent image is formed on the photosensitive sheet 1, and the latent image area is stocked in the buffer portion.

When the exposure process is completed, the pressure development process is subsequently performed. During the pressure developing process, the supply shaft 2 is locked, and the winding shaft 9 is rotated in the winding direction of the photosensitive sheet. The buffer roller 6 moves in the direction of arrow B, and conveys the latent-image-formed photosensitive sheet stocked in the buffer section to the pressure roller side. Further, the pressure roller 7 is pressed and the image receiving sheet is supplied to the position of the pressure roller. The image receiving sheet is fed at a timing so as to overlap the latent image on the photosensitive sheet. With such an operation, the image receiving sheet is superposed on the latent image on the photosensitive sheet 1 and pressed by the pressure roller 7, so that the latent image on the photosensitive sheet 1 is visualized and transferred to the image receiving sheet.

Although the image forming process is performed as described above, the initial setting of the photosensitive sheet is usually performed before the image forming process. The initial setting is to eliminate the looseness and tension of the photosensitive sheet. The buffer roller 6 is moved in the directions A and B, and a predetermined winding tension is applied to the winding shaft 9 when moving the buffer roller 6 in the direction B. As a result, the tension of the photosensitive sheet 1 is set to a specified value. Further, the void lamp 4 is also turned on during this initial setting operation.

A halogen lamp, an LED, or the like is used as the void lamp 4. The void lamp 4 is provided by arranging several lamps in the vertical direction in FIG. 2, and a necessary lamp is turned on according to the size of an image to be formed to perform void exposure. For example, as shown in FIG. 3A, when the formed image is B5 size, B5 size width a at the center of the photosensitive sheet.
Is set, and the lamps in the opposite areas are lit to expose both ends thereof. Further, as shown in FIG. 7B, in the case of A4 size, the A4 size width b is set in the central portion, and the lamp is lit to expose both ends thereof.

FIG. 1 is a flowchart showing a processing procedure at the time of void exposure processing in the same apparatus.

First, when the print switch is operated, the necessary void lamp is turned on, and at the same time, the buffer roller 6 is moved in the direction of arrow A to start the initial setting operation (n1 → n2 →
n3). The buffer roller 6 moves in the direction of arrow A for T1 time and pulls out the photosensitive sheet 1 (n4). Then, after a lapse of T1 time, the movement starts in the direction of the arrow B. At that time, since a force in the winding direction is applied to the winding shaft 9, a constant tension is applied to the photosensitive sheet 1. And the buffer roller 6
When the sensor provided at the home position of turns on, the buffer roller 6 and the winding shaft 9 stop (n5 → n6
→ n7).

The above-described operations of n1 to n7 are the initial setting operation, and when the processing setting operation is completed, the buffer roller 6 subsequently starts moving in the direction of arrow A, and the exposure processing as the image forming processing is performed (n8). When the exposure process is completed, the void lamp 4 is turned off (n9 → n10).

If the length of the photosensitive sheet 1 pulled out from the supply shaft during the initial setting operation is l1, the distance l2 between the exposure part on the exposure table 5 and the exposure area of the void lamp 4 must be sufficiently longer than l1. is there. This is because the photosensitive sheet located on the exposure table 5 at the time of starting the exposure process needs to be a sufficiently void-exposed region, and this sufficiently long distance provides a stable light amount to the lamp. It is proportional to the time it takes to get out.

(G) Effect of the Invention According to the present invention, the void lamp is turned on in advance to start the void exposure before the exposure processing is started, and the photosensitive sheet is also conveyed during this period, so that the front end portion of the image is sufficient. Void exposure is performed, and the tip of the image does not become dirty.

Since this void exposure is performed at the same time as the initial setting operation of the photosensitive sheet, it is not necessary to provide a special time frame, and no time is wasted. Moreover, since the control is started at the same time as the start of the initial setting operation, it is not necessary to specifically retroactively control the time before the start of exposure, and the control is simplified.

[Brief description of drawings]

FIG. 1 is a flowchart showing a processing procedure of void lamp control in a void lamp control device according to an embodiment of the present invention, FIG. 2 is a diagram showing a configuration of a photosensitive sheet conveying system, FIG. 3 (A), FIG. 6B is a diagram showing a void exposure region on the photosensitive sheet. 1 ... Photosensitive sheet, 2 ... Supply shaft, 4 ... Void lamp, 5 ... Exposure base, 6 ... Buffer roller, 9 ... Winding shaft.

Continuation of the front page (56) References JP-A-63-157152 (JP, A) JP-A-1-267626 (JP, A) Actually developed 63-60142 (JP, U)

Claims (1)

(57) [Claims] 1. An image forming apparatus for performing an initial setting of a photosensitive sheet by operating the photosensitive sheet conveying system and pulling out a slightly long photosensitive sheet before the start of exposure processing, immediately before the exposure unit of the photosensitive sheet conveying system. A void lamp control device, wherein a void lamp for exposing both ends of a photosensitive sheet is arranged, and a means for starting the exposure of the void lamp during the initial setting operation is provided.