JPH04204841A - Void lamp controller - Google Patents

Abstract

PURPOSE:To prevent generation of a stain at the top of an image by arranging a void lamp exposing both end parts of a sensitized sheet in just front of a sensitized sheet carrying system exposing part, and starting the exposing of the void lamp at the time of an initial setting action. CONSTITUTION:When a printing switch is operated, a necessary void lamp is turned on, simultaneously, a buffer roller 6 is moved in the direction of the arrow A, to start the initial setting action, and the buffer roller 6 is moved in the direction of the arrow A only for T1-time, to pull out the sensitized sheet 1. The buffer roller 6 is started to be moved in the opposite direction of the arrow A after the T1-time, and force in a taking up direction is given to a taking up shaft 9, at that time, so that constant tension is given to the sensitized sheet 1. When a sensor provided on the home position of the buffer roller 6 is turned on, the buffer roller 6 and the taking up shaft 9 are stopped. When the above-mentioned setting actions for processing is completed, continuously, the buffer roller 6 is started to be moved in the direction of the arrow A, and the exposing processing is carried out. Thus, the generation of a stain at the top end of the image is evaded.

Description

Detailed Description of the Invention (a) Industrial Application Field This 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 to light. The present invention relates to a void lamp control device that performs exposure processing to prevent development from occurring.

('b) Conventional technology Photosensitive sheet with pressure sensitivity (areas exposed to light do not transfer dye onto the image-receiving sheet even if pressure is applied, but areas not exposed to light transfer dye to the image-receiving sheet) In an image forming apparatus that performs image forming processing using a photosensitive sheet, the photosensitive sheet is wound around a supply shaft, and the photosensitive sheet is passed from the supply shaft through a photosensitive sheet transport system including an exposure section, a buffer section, and a pressure development section to a take-up shaft. I try to wind it up. The photosensitive sheet is exposed to image-forming light such as reflected light from the original or laser light in the exposure section to form a latent image, and is pressed while being overlapped with the image-receiving sheet in the pressure development section to develop the latent image. image and transfer it onto an image-receiving sheet.

By the way, when forming a latent image on a photosensitive sheet using imaging light, in most cases the image width (width that is irradiated with imaging light)
is narrower than the width of the photosensitive sheet itself. Therefore, if pressure development is performed in that state, development will occur at both ends that are not exposed to light, resulting in stains on the widthwise edges of the image-receiving sheet. To prevent this staining, a void lamp is placed just before the exposed area, and by lighting the void lamp during the exposure process, both ends of the photosensitive sheet are exposed, and the dye at both ends is exposed. This prevents the liquid from adhering to the image receiving sheet.

(C1 Problem to be Solved by the Invention) However, in the past, void exposure was insufficient at the leading edge of the image, resulting in stains at both ends of the image-receiving sheet. This is due to two reasons. This is because the void lamp is provided in front of the exposure area, so if the void lamp is turned on at the same time as exposure starts, the area between the void lamp and the exposure area will not be exposed. This was because the amount of light at the start of lighting of the lamp was unstable, so a sufficient amount of light was not provided, and some dye was transferred.

To solve these problems, before starting the exposure process,
1. The time tts for exposing the area between the void lamp and the exposure section, and the time t2 until the amount of light from the void lamp stabilizes. +1. It is conceivable to turn on the void lamp retroactively, but this method results in the inconvenience of wasting time and complicating control.The purpose of the present invention is to avoid wasting time, Another object of the present invention is to provide a void lamp control device that can eliminate the lack of void exposure with simple control.

(d) Means for solving the problem By the way, in an image forming apparatus that performs image forming processing using a photosensitive sheet, if there is excessive slack or tensile force is applied to the photosensitive sheet during image formation, the formed image will be damaged. Distortion may occur. Therefore, in an image forming apparatus that forms an image using a photosensitive sheet, the photosensitive sheet is initially set before starting an exposure process, which is the first stage of the image forming process. This is an operation in which the photosensitive sheet on the supply shaft is pulled out to the buffer section, and then a predetermined torque is applied to pull the photosensitive sheet on the buffer section toward the take-up shaft, so that the photosensitive sheet is in a state with neither slack nor tension. Set. The present invention utilizes the initial setting process performed before the start of the exposure process, and is characterized by providing means for starting the void lamp exposure at the time of the initial setting operation.

(e) Function In the present invention, lighting of the void lamp is started during an initial setting operation in which a photosensitive sheet is pulled out and initially set before exposure processing. Therefore, the photosensitive sheet pulled out during the initial setting operation is exposed by the void lamp, and the area to which the leading edge of the image corresponds becomes the void exposure area. Further, since the void lamp is lit in advance, void exposure can be performed with a sufficient amount of light.

Here, if the time to expose the area between the void lamp and the exposure section is tI, and the time until the void lamp light amount stabilizes is 1t, the time required for the initial setting operation is "1.+1". .”, but the void lamp is placed just before the exposure area, and C2
Since the time is also sufficiently short, "t, +t2" is shorter than the time required for initial setting.

(fl Example FIG. 2 is a diagram showing a photosensitive sheet conveyance system.

A photosensitive sheet 1 is wound around a supply shaft 2. The supply shaft 2 is housed in a cartridge (not shown) and is protected from external light and external pressure. The photosensitive sheet 1 is pulled out from the supply shaft 2, and is loaded with a sprocket roller 3, a void lamp 4, an exposure stage 5 constituting an exposure section, a buffer roller 6 constituting a buffer section, a pressure roller 7 constituting a pressure developing section, and
It is wound onto a winding shaft 9 via a peeling roller 8.

The photosensitive sheet conveyance system is composed of the above-mentioned supply shaft 2, sprocket roller 3, . . . take-up shaft 9.

Here, the processing during image formation will be briefly explained.

Note that in the image forming process, a pressure development process is performed after the exposure process is completed. This is because the photosensitivity and pressure sensitivity of the photosensitive sheet 1 are significantly different, so by changing the conveyance speed of the photosensitive sheet when performing exposure processing and when performing pressure development processing, processing corresponding to each sensitivity can be achieved. It can be carried out.

The exposure process is performed by moving the buffer roller 6 in the direction indicated by the arrow. During exposure processing, the supply shaft 2 is unlocked and the take-up shaft 9 is opened. Then, the pressure roller 7 is brought into a pressure released state, and the buffer roller 6 moves in the direction indicated by the arrow. As a result, the photosensitive sheet 1 is pulled out from the supply shaft 2, and the photosensitive sheet is stocked in the part where the buffer roller 6 is pulled out, that is, in the buffer section. Imaging light such as laser light or the like is guided, a latent image is formed on the photosensitive sheet 1, and the latent image area is stored in the buffer section.

After the exposure process is completed, a pressure development process is subsequently performed. During the pressure development process, the supply shaft 2 is locked and the winding shaft 9 is rotated in the direction of winding up the photosensitive sheet. The buffer roller 6 moves in the direction of arrow B and conveys the photosensitive sheet on which the latent image has been formed, which has been stocked in the buffer section, toward the pressure roller. Further, the pressure roller 7 is pressurized, and the image receiving sheet is supplied to the pressure roller position. The image-receiving sheet is fed at a timing such that it overlaps the latent image on the photosensitive sheet. Through this operation, the image receiving sheet is superimposed on the latent image on the photosensitive sheet 1 and pressed by the pressure roller 7, and 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 slack and tension in the photosensitive sheet.The buffer roller 6 is moved in the directions of arrows A and B, and when moving in the direction of B, a predetermined winding tension is applied to the winding shaft 9. By doing this, the tension of the photosensitive sheet 1 is brought 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 a system in which several lamps are arranged vertically in FIG. As shown in A), when the formed image is B5 size, a B5 size width a is set at the center of the photosensitive sheet, and lamps in opposing areas are turned on to expose both ends thereof. In addition, as shown in the same figure (B), A4
In the case of the size, an A4 size sheet is set in the center, and a lamp is turned on to expose both ends of the sheet.

FIG. 1 is a flowchart showing the processing procedure during void exposure processing in the same apparatus.

First, when the print switch is operated, the necessary void lamp is lit, and at the same time, the buffer roller 6 is moved in the direction of the arrow to start the initial setting operation (nl-n2
→n3), the buffer roller 6 moves in the direction of the arrow for a time T1 and pulls out the photosensitive sheet 1 (n4), and after the time T1, starts moving in the direction of the arrow B, at which time the winding shaft 9 is wound. Since a force is applied in the pick direction, a constant tension is applied to the photosensitive sheet 1. Then, when the sensor provided at the home position of the buffer roller 6 is turned on, the buffer roller 6 and the winding shaft 9 are stopped (n5-n6-n7).

The above operations n1 to n7 are the initial setting operations, and when the processing setting operation is completed, the buffer roller 6 subsequently starts moving in the direction of the arrow, and exposure processing as image forming processing is performed (n8), and then exposure When the process is completed, the void lamp 4 is turned off (n9→n1o).

Note that, assuming that the length of the photosensitive sheet 1 pulled out from the supply shaft during the initial setting operation is 11, the distance 12 between the exposure section on the exposure table 5 and the exposure area by the void lamp 4 needs to be sufficiently longer than 11. Yes, this is because the photosensitive sheet located on the exposure stage 5 when the exposure process starts needs to be in a sufficiently void-exposed area, and this sufficiently long distance is necessary for the lamp to stabilize. It is proportional to the time it takes to be able to emit light.

Effects of the Invention According to the invention, the void lamp is lit in advance before the exposure process is started to start void exposure, and during this time the photosensitive sheet is also conveyed, so even the leading edge of the image can be sufficiently exposed to voids. This prevents dirt from forming on the leading edge of the image.

This void exposure is performed at the same time as the initial setting operation of the photosensitive sheet, so there is no need to set a special time frame and no time is wasted.Also, since the void exposure is started at the same time as the initial setting operation starts, there is no need to set a special time frame. There is no need to go back and control the previous time, making control easier.

[Brief explanation of the drawing]

FIG. 1 is a flowchart showing the processing procedure for void lamp control in a void lamp control device according to an embodiment of the present invention, FIG. 2 is a diagram showing the configuration of a photosensitive sheet conveyance system, FIG. 3(A), (B) is a diagram showing void exposure areas on the photosensitive sheet. 1-photosensitive sheet, 2-supply shaft, 4-void lamp, 5-
Exposure table, 6-buffer roller, 9-take-up shaft.

Claims (1)

[Claims] (1) In an image forming apparatus that initializes the photosensitive sheet by operating the photosensitive sheet conveying system and pulling out a slightly long photosensitive sheet before the start of exposure processing, the photosensitive sheet is placed immediately before the exposure section of the photosensitive sheet conveying system. A void lamp control device characterized in that a void lamp is arranged to expose both ends of the void lamp, and means for starting exposure of the void lamp at the time of the initial setting operation is provided.