JP2589868B2 - Image forming device - Google Patents

Description

The present invention relates to, for example, a microcapsule-coated photosensitive sheet containing a photocurable material and a coloring dye, and a developing material that reacts with the coloring dye to form a color. The present invention relates to an image forming apparatus that forms an image by pressing a coated image receiving sheet in a superimposed state.

(Prior Art) For example, JP-A-58-88739 discloses a photosensitive sheet coated with a microcapsule containing a photocurable material and a coloring dye, and a developing material which reacts with the coloring dye to form a color. An image forming apparatus for forming an image using a coated image receiving sheet is disclosed.

In such an image forming apparatus, an image is formed as follows. First, when a document image is exposed on a photosensitive sheet, the microcapsules in the light-irradiated portion are selectively cured to form a latent image corresponding to the document image. The photosensitive sheet on which the latent image is formed is overlaid on the image receiving sheet coated with the developing material by a pressure device as a pressure developing unit, and both are pressed. As a result, the uncured microcapsules on the photosensitive sheet are destroyed, the coloring dye contained therein flows out, and the discharged coloring dye reacts with the developing material on the image receiving sheet to form a color. Thus, an image corresponding to the document image is formed on the image receiving sheet.

The photosensitive sheet is housed in a roll shape and wound around a supply shaft in a cartridge, pulled out of the cartridge by a buffer roller,
After passing through the exposure and pressure development processes, it is wound again on the winding shaft in the cartridge.

(Problems to be Solved by the Invention) In such an image forming apparatus, the photosensitive sheets after being used for image formation are sequentially wound on the winding shaft, and thus are wound on the winding shaft. The diameter of the used photosensitive sheet gradually increases. When the amount of used photosensitive sheet taken up by the take-up shaft increases, the photosensitive sheet taken up by the take-up shaft is pulled back when the photosensitive sheet is pulled out by the buffer roller. Since the withdrawal amount is reduced, the conveyance of the photosensitive sheet exposed to the image and conveyed to the pressure developing device tends to be delayed. Therefore, the image exposure position on the photosensitive sheet is delayed with respect to the image receiving sheet superimposed on the photosensitive sheet in the pressure development process, and as a result, the image formed on the image receiving sheet is delayed by the delay of the photosensitive sheet. There is a possibility that a position shift occurs and an image is not formed at a predetermined position of the image receiving sheet.

The present invention has been made to solve such a problem, and an object of the present invention is to correct a conveyance delay of a photosensitive sheet after an image is exposed so that an image exposure position on the photosensitive sheet and a receiving sheet are misaligned. An object of the present invention is to provide an image forming apparatus which can be developed under pressure without causing any trouble.

(Means for Solving the Problems) An image forming apparatus according to the present invention exposes an image while moving a roll-shaped photosensitive sheet coated with a photosensitive pressure-sensitive material in a predetermined direction, and applies the exposed photosensitive sheet to a developing material. An image forming apparatus that winds a used photosensitive sheet with a take-up shaft after being superposed on an image receiving sheet coated with, and pressure-developed, and is orthogonal to a moving direction of the photosensitive sheet at an image exposure position. The photosensitive drum has a buffer roller that is capable of reciprocating in a direction, draws out the photosensitive sheet so as to be conveyed in a predetermined direction at an image exposure position by moving in one direction, and moves the photosensitive sheet to a pressure development process by moving in the other direction. And controlling the moving speed of the photosensitive sheet by the buffer roller to the pressure developing step in accordance with the winding amount of the photosensitive sheet wound on the winding shaft. It becomes the above-described object can be achieved.

(Operation) In the image forming apparatus of the present invention, the image is exposed on the photosensitive sheet moved in a predetermined direction by the movement of the buffer roller, and then the photosensitive sheet is pressed by the movement of the buffer roller in the opposite direction. It is transported to a development process. The photosensitive sheet that has undergone the pressure development step is sequentially wound by a winding shaft. Conveyance of the photosensitive sheet to the pressure development process by the buffer roller is controlled according to the amount of the photosensitive sheet wound on the winding shaft, and the moving speed of the photosensitive sheet to the pressure development process by the buffer roller is controlled. Thus, the image exposure position of the photosensitive sheet is always superimposed on a predetermined position of the image receiving sheet in an aligned state.

(Example) An example of the present invention will be described below.

FIG. 2 is a front longitudinal sectional view of a copying machine employing the image forming apparatus of the present invention. The copying machine has a glass document table 2 provided on the upper surface of a copying machine body 1. A document 3 for forming a copy image is placed on the document placing table 2. A light-transmitting sheet projecting section 4 for projecting an image formed on the light-transmitting sheet into the copying machine main body 1 is provided at an upper portion of one side surface of the copying machine main body 1, and is provided below the light-transmitting sheet projecting section. Is provided with a manual paper feed unit 5 and a paper feed cassette 6. The sheet cassette 6 contains, for example, an image receiving sheet 7 coated with an acidic developing material. The image receiving sheet 7 is superposed on the photosensitive sheet and is subjected to pressure development, whereby an image is formed on the image receiving sheet 7. On the other side of the copying machine body 1, there is provided a paper discharge tray 8 on which the image receiving sheet 7 on which an image has been formed is placed.

An optical system 10 is provided above the copying machine body 1. The optical system 10 includes a pair of light sources 11 for irradiating the original 3 placed on the original placing table 2 on the upper surface of the copying machine main body 1 with light.
The light sources 11 and 12 can reciprocate in the direction indicated by the arrow C and in the opposite direction. Light emitted from the light sources 11 and 12 and reflected from the document 3 is reflected in a direction opposite to the direction indicated by the arrow C by the mirror 13 that moves integrally with the light sources 11 and 12. The light reflected by the mirror 13 is a mirror case
The traveling direction is reversed by a pair of reflection mirrors 15 and 16 in 14. The light whose traveling direction is reversed by the pair of mirrors 15 and 16 passes through the lens unit 17,
The light is reflected by the mirror 18 and radiated toward an exposure plate 30 provided substantially at the center of the copying machine body 1.

A cooling fan 65 for cooling the pair of light sources 11 and 12 is attached to the optical system 10.
Reciprocates integrally with both light sources 11 and 12.

Below the mirror case 14, a photosensitive sheet bucket 20 is provided.
Are arranged. A cartridge 21 covered by a case made of a light-shielding material is mounted on the photosensitive sheet bucket 20. The cartridge 21 has a roll-shaped photosensitive sheet 23 that is wound and housed around an internal supply shaft 22. The photosensitive sheet 23 is formed by coating a base sheet made of a metal, a synthetic resin, or the like with microcapsules, which are photosensitive pressure-sensitive materials having a particle size of about 10 to 20 μm and containing a coloring dye such as a leuco dye and a photocurable substance. ing. The photosensitive sheet 23 is pulled out via a guide roller 26 arranged near the supply shaft 22.

Positioning holes (not shown) for use in sequentially feeding out the photosensitive sheet 23 from the photosensitive sheet bucket 20 are provided along both sides in the width direction of the photosensitive sheet 23 along its longitudinal direction. The positioning holes are fitted into the tractor roller 24 sequentially. Power is transmitted to the tractor roller 24 via a clutch (not shown). The tractor roller 24 causes the photosensitive sheet 23 to be fed out of the photosensitive sheet bucket 20 and conveyed to the exposure plate 30.

The exposure plate 30 is disposed so as to be orthogonal to the light reflected by the mirror 18 in the optical system 10, and the mirror 18
The photosensitive sheet 23 is conveyed along the surface facing. A heater 31 is attached to the surface of the exposure plate 30 opposite to the surface on which the photosensitive sheet 23 is conveyed, and the heater 31 keeps the exposure plate 30 at a predetermined temperature.
The photosensitive sheet 23 conveyed along 30 is set to a predetermined temperature. Thereby, the sensitivity of the photosensitive sheet 23 is maintained in a predetermined state.

The photosensitive sheet 23 conveyed along the exposure plate 30 is irradiated with the reflected light of the original 3 by the optical system 10. Thereby, the microcapsules on the photosensitive sheet 23 are selectively photo-cured, and a latent image corresponding to the document image is formed on the photosensitive sheet 23.

Further, the light transmitting sheet projection unit 4 provided on the side surface of the copying machine main body 1 is in a state facing the exposure plate 30, and
When copying the image of the light-transmitting sheet, the light projected from the light-transmitting sheet projection unit 4 is directly conveyed along the exposure plate 30 by moving the mirror 18 in the optical system 10. The photosensitive sheet 23 is irradiated.

In the vicinity of the lower end of the exposure plate 30, a guide roller 32 and a buffer roller 33 are sequentially provided along the conveying direction of the photosensitive sheet 23. The guide roller 32 is disposed so as to face the microcapsule-coated surface of the photosensitive sheet 23 to be conveyed. Buffer roller 33
Is movable from a home position facing the back surface of the photosensitive sheet 23 in directions indicated by arrows A and B perpendicular to the conveying direction of the photosensitive sheet 23 on the exposure plate 30.
The movement is controlled by a control device 70 shown in the figure. Photosensitive sheet conveyed along exposure plate 30
Reference numeral 23 is wound around the buffer roller 33, and its direction is directed to the photosensitive sheet bucket 20 side. The photosensitive sheet 23 wound around the buffer roller 33 passes through the pressure developing device 50 and is wound around the winding shaft 25 of the photosensitive sheet bucket 20.

The buffer roller 33 is rotatable in both the forward and reverse directions, is moved in the direction of arrow A from the home position described above, and is set to the drawn-out position 33a indicated by a broken line. When the buffer roller 33 is moved to the extraction position 33a, the photosensitive sheet 23 is extracted by a predetermined length, and is conveyed along the exposure plate 30.

The copier main body 1
The image receiving sheet 7 conveyed by the conveying mechanism 40 is fed from the manual sheet feeding unit 5 or the sheet feeding cassette 6 provided on the side of the image forming apparatus. The image receiving sheet 7 is transferred to the pressure developing device 50 in synchronization with the photosensitive sheet 23 on which the latent image is formed by exposing the image while being conveyed along the exposure plate 30 by the conveying mechanism 40. Supplied.

The pressure developing device 50 is provided with a large-diameter roller 51, a small-diameter roller 52, and two crown rollers 53. Between the large-diameter roller 51 and the small-diameter roller 52, the two sheets 7 and 23 that have been superposed pass and are developed under pressure. The pressure developing force is applied by a crown roller 53 that is pressed against the small-diameter roller 52. In the pressure building apparatus 50, the image receiving sheet 7 and the photosensitive sheet 23 on which the image has been exposed are pressurized in a superimposed state, and as described above, only the uncured microcapsules that have not been cured by light are emitted. The coloring sheet is destroyed, and a coloring dye such as a leuco dye flows out of the photosensitive sheet 23 to the image receiving sheet 7, and the coloring dye reacts with the developing material of the image receiving sheet 7 to form the image receiving sheet 7.
An image is formed thereon.

Thus, the image receiving sheet 7 developed by the pressure developing device 50 is supplied to the glossing device
The image is conveyed to 60 and pressurized and heated by the glossing device 60 to give gloss to the image. The glossy image receiving sheet 7 is discharged onto the discharge tray 8 of the copying machine main body 1 by the discharge device 70 disposed on the discharge tray 8 side of the glossing device 60.

The winding amount of the photosensitive sheet 23 wound by the winding shaft 25 in the cartridge 21 of the photosensitive sheet 23 is because the total length of the roll-shaped photosensitive sheet 23 mounted on the supply shaft 22 in the cartridge 21 is set in advance. 2, buffer roller
The calculation is performed based on the number of times of the image forming operation by the control device 70 that controls the movement of 33. Then, the control device 70
Calculates the diameter of the photosensitive sheet 23 wound on the winding shaft 25 based on the amount of winding of the photosensitive sheet 23 wound on the winding shaft 25, and based on the calculation result, the above-described buffalo It controls the movement of Ra33.

The operation of the image forming apparatus having such a configuration will be described below. In the exposure process of the photosensitive sheet 23, the buffer roller 33 is moved from the home position to the extraction position 33a by the control device 70, and the photosensitive sheet 23 is pulled out in the direction orthogonal to the conveying direction along the exposure plate 30. The sheet is conveyed along the exposure plate 30 at a predetermined speed. During this conveyance, the photosensitive sheet 23 is exposed to an image. Then, when the buffer roller 33 reaches the drawing position 33a and the exposure of the photosensitive sheet 23 ends, the buffer roller 33 is moved in the direction opposite to the drawing direction, and the photosensitive sheet 23 is
It is transported to the pressure developing device 50.

At this time, when the roll-shaped photosensitive sheet 23 is initially mounted on the supply shaft 22 and the photosensitive sheet 23 is hardly wound on the winding shaft 25, as shown in FIG. The photosensitive sheet 23 in the state of being pulled out by the buffer roller 33 moved to the drawing position 33a has the buffer roller 33 moved for a predetermined time T in the direction opposite to the drawing direction indicated by the arrow B, and When the winding shaft 25 is rotated to wind the photosensitive sheet 23, the photosensitive sheet 23 is conveyed to the pressing device 50 by a predetermined amount. As a result, the buffer roller 33 is moved at a predetermined acceleration to a position 33b indicated by a dashed line in FIG. 1, and has a predetermined moving speed at the position 33b. After passing through the position 33b, the buffer roller 33 is moved in the direction of arrow B at a constant moving speed, and is positioned at the home position. As a result, the photosensitive sheet 23 is sequentially transferred to the large-diameter roller 51 and the small-diameter roller 52 in the pressure developing device 50.
Is passed through the pressure point P.

At this time, the leading end of the image receiving sheet 7 is located at a position away from the pressure point P in the pressure developing device 50 by a predetermined distance, and the distance is from the pressure point P to the position 33b of the buffer roller 33. Since the distance is shorter than the distance, the movement of the buffer roller 33 in the direction opposite to the pullout direction is started before the predetermined time T elapses (T−
T ′), the image receiving sheet 7 is moved by the transport mechanism 40 to the pressing device 50.
To the pressure point P.

Thus, the image exposure position of the photosensitive sheet 23 and the leading end of the image receiving sheet 7 in the conveying direction coincide with each other at the pressure point P in the pressure developing device 50, and are sequentially superimposed at the pressure point P. And pressurized. Then, the uncured microcapsules on the photosensitive sheet 23 are broken, and an image is formed on the image receiving sheet 7.

In this way, the roll-shaped photosensitive sheet 23 attached to the supply shaft 22 is sequentially pulled out, and after the image is exposed on the photosensitive sheet 23, an image is formed on the image receiving sheet 7. The used photosensitive sheets 23 are sequentially wound around the winding shaft 25. Then, as the photosensitive sheet 23 is wound on the winding shaft 25, the diameter of the photosensitive sheet 23 is sequentially increased as shown by a two-dot chain line in FIG. The control device 70 that controls the movement of the buffer roller 33 calculates the length of the photosensitive sheet 23 fed from the supply shaft 22 based on the number of image forming operations, and based on the length, the winding shaft The diameter of the photosensitive sheet 23 wound around 25 is calculated. Then, in proportion to the increase in the diameter of the photosensitive sheet on the winding shaft 25, the moving time T required for the buffer roller 33 to reach a constant speed is increased by ΔT with respect to the initial time T. As a result, the buffer roller 33 is moved at a constant speed higher than the previous speed after passing the position 33b after the elapse of the moving time T (= T + ΔT). As a result, the time required for the image exposure position on the photosensitive sheet 23 to reach the pressing point P in the pressing device 50 is gradually increased in proportion to the winding diameter of the photosensitive sheet 23 by the winding shaft 25.

At this time, the image receiving sheet 7 is conveyed after a lapse of a predetermined time from the start of the movement of the buffer roller 33 in the direction opposite to the drawing direction, but the delay time T ′ from the movement start time of the buffer roller 33 is also earlier by ΔT. (T '= T'
+ ΔT). As a result, the front end of the image exposure position of the photosensitive sheet 23 and the front end of the image receiving sheet 7 are sequentially superimposed on each other in a state where they coincide with each other at the pressing point P, and are pressed.

Thereafter, each time the winding diameter of the photosensitive sheet 23 by the winding shaft 25 increases, the control device 70 sequentially increases the transport speed of the photosensitive sheet 23 to which the image has been exposed to the pressing point P, and The sheet 23 and the image receiving sheet 7 are surely overlapped in an aligned state and pressed.

(Effect of the Invention) As described above, the image forming apparatus of the present invention responds to the fluctuation of the winding diameter of the used photosensitive sheet by the winding shaft,
Since the speed of the photosensitive sheet conveyed to the pressure developing device is controlled, in the pressure developing device, the photosensitive sheet and the image receiving sheet are constantly superimposed and pressed in an aligned state, and the image is placed at a predetermined position on the image receiving sheet. Is formed.

[Brief description of the drawings]

FIG. 1 is a schematic view of a main part of an example of an image forming apparatus of the present invention,
FIG. 2 is a block diagram of the copying machine. 7 ... image receiving sheet, 21 ... cartridge, 23 ... photosensitive sheet, 25 ... winding shaft, 30 ... photosensitive plate, 33 ... buffer roller, 40 ... transport mechanism, 50 ... pressure developing device, 70 ……
Control device.

Claims (1)

(57) [Claims] An image is exposed while a roll-shaped photosensitive sheet coated with a photosensitive pressure-sensitive material is moved in a predetermined direction, and the exposed photosensitive sheet is overlapped with an image receiving sheet coated with a developing material and pressed. An image forming apparatus that winds a used photosensitive sheet around a take-up shaft after development, and is capable of reciprocating in a direction orthogonal to a moving direction of the photosensitive sheet at an image exposure position, to one side. And a buffer roller for moving the photosensitive sheet to a pressure development process by moving the photosensitive sheet to a predetermined direction at the image exposure position. An image forming apparatus, wherein a moving speed to a pressure developing step is controlled in accordance with a winding amount of a photosensitive sheet wound around the winding shaft.