JPH03215866A - Exposure device - Google Patents

Abstract

PURPOSE:To make the whole surface of a photosensitive material sheet contact with a drum and to submit it to exposure under an excellent state even when the photosensitive material sheet has a winding inclination by holding and fixing the leading edge part and the trailing edge part of the photosensitive material sheet to the outside circumferential surface of the drum and simultaneously fixing and releasing the trailing edge part with the aid of interlocking with the rotation of the drum. CONSTITUTION:The photosensitive material sheet S whose leading edge part is inserted in a leading edge inserting plate 7 is wound to the outside circumferential surface of the drum 1 while it is sucked by air in accordance with the clockwise rotation of the drum 1. A press plate 41 is passed through the comb-teeth shaped blade of a third guide member 23 while it is rotated. Then, the plate 41 faces to the outside circumferential surface of the drum 1 so as to press the trailing edge part of the sheet S to the drum 1 instead of the guide member 23 which lightly presses the sheet S. Since tee leading edge part of the sheet S is inserted in the plate 7 and held and the trailing edge part is pressed by the plate 41 besides in such a way, the whole surface thereof is wound to the outside circumferential surface of the drum 1 by the air suction under a contact state. Therefore, even when the sheet S has the winding inclination, it becomes an excellent exposure feasible state and it is wound to the outside circumferential surface of the drum 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention is applied to a printer in which a photosensitive material sheet such as photographic paper or film is wound around a drum, such as in a plotter for making a newspaper block copy. The present invention relates to an exposure device that exposes a light-sensitive material sheet to light while rotating it.

[Conventional technology]

The latest newspaper production technology is the electronic editing system (CTS), and a plotter controlled by a computer is used to produce the block copy. This plotter uses laser light to transfer images such as characters and photographs that have been edited by a computer and converted into dot images onto a sheet of sensitive material such as photosensitive film or photographic paper. This plotter scans a sensitive material sheet with a laser beam or uses an LED
This is a device that exposes a sensitive material sheet to a dot image corresponding to an image by irradiating light, etc. The sensitive material sheet exposed with a plotter is then developed and fixed to produce a printing plate. In such a plotter, it is necessary to move the sensitive material sheet at the exposure position of the irradiation light, and the plotter has traditionally been equipped with a drum that rotates at a position close to the exposure position.
Exposure can be performed in the X and Y directions by rotating this drum and manipulating the light. Additionally, this drum is capable of air suction in order to fix the photosensitive material sheet.

The drum is made of an air-permeable porous material such as a mesh or punched metal in order to adsorb air to the photosensitive material sheet, and the photosensitive material sheet is wound around the outer peripheral surface of the drum by air adsorption. In addition, a tip insertion plate into which the tip of the photosensitive material sheet is inserted is provided at a predetermined position of this drum.
The photosensitive material sheet supplied to the drum is inserted into this leading edge insertion plate and stopped, thereby positioning the sheet with respect to the drum and holding the leading edge of the sheet.

Such a drum rotates in the vicinity of the exposure position with the photosensitive material sheet adsorbed and held on its outer peripheral surface, and this rotation supplies the photosensitive material sheet in the sub-scanning direction.

On the other hand, the laser beam is scanned in a main scanning direction perpendicular to this direction to expose a dot image on the photosensitive surface of the photosensitive material sheet.

[Problem to be solved by the invention]

By the way, there are two types of photosensitive material sheets: cutting type, which is pre-cut to a predetermined length;
There is a roll type which is wound into a roll and is cut to a predetermined length when being supplied to a drum.

When winding such a photosensitive material sheet around a drum, the cutting type photosensitive material sheet is capable of good air adsorption and can be reliably held on the drum.

However, roll-type sensitive material sheets often have curls themselves, and these curls reduce the adhesion to the drum depending on the winding direction. In particular, when a roll type is wound so that the photosensitive surface is on the inside, the photosensitive material sheet is wound around the drum with the photosensitive surface facing upward, causing the photosensitive material sheet to be warped against the drum. However, there is a problem in that the leading and trailing ends of the drum are lifted off the outer surface of the drum, making it impossible to accurately expose dot images on these parts.

For this reason, attempts have been made to increase the adsorption force of the air adsorption, but in this case, not only does it create an undesirable dent in the part of the photosensitive material sheet that corresponds to the hole in the drum, but it also causes the winding to curl strongly. The effectiveness of this method is still poor for the core of the photosensitive material sheet.

The present invention has been made in consideration of these circumstances, and an object of the present invention is to provide an exposure apparatus that can reliably wind even a roll-type sensitive material sheet around a drum.

[Means to solve the problem]

In order to achieve the above object, the present invention provides an apparatus for exposing a photosensitive material sheet wound in a roll shape by irradiating light onto the photosensitive material sheet wound around the outer peripheral surface of a rotating drum by air suction. , a cutter provided on the supply path of the photosensitive material sheet to cut the photosensitive material sheet into a predetermined length, and a cutter provided on the outer peripheral surface of the drum into which the leading end of the photosensitive material sheet is inserted. a tip insertion plate that rotates toward and away from the outer circumferential surface of the drum, and a presser member that presses and releases the rear end of the sacrificial sheet; and rotating means for rotating the presser member so as to rotate the holding member.

[Effect]

The feeding means feeds the photosensitive material sheet to the drum so that it faces in the counter-winding direction, and the tip insertion plate abuts the tip of the fed photosensitive material sheet to position and hold the tip of the photosensitive material sheet. I do. The pressing member is rotated by the rotation means and presses the rear end of the photosensitive material sheet against the outer peripheral surface of the drum.

As a result, the front end and the rear end of the photosensitive material sheet are fixed, so that the entire surface is tightly wrapped around the outer surface of the drum by air suction.

〔Example〕

FIGS. 1 and 2 show an embodiment in which the present invention is applied to the exposed portion of a plotter for preparing a newspaper plate. A drum 1 on which a photosensitive material sheet S is wound around its outer peripheral surface is supported so as to be rotatable in forward and reverse directions, and a feeding mechanism 2 serving as a feeding means for the photosensitive material sheet S is provided on the upstream side of the drum 1 (on the left side in the illustrated example).
An endless conveyor 3 is provided below the drum 1.

The sensitive material sheet S is wound into a roll and stored in a magazine 4, and is pulled out from the magazine 4 by a supply mechanism 2 in a direction opposite to the winding direction and wound around the drum 1. After the drum 1 rotates and the entire surface is exposed to light, it is taken out from the drum 1 to the conveyor 3 and subjected to development processing.

The drum 1 holds the photosensitive material sheet on its outer peripheral surface by air adsorption, and is a porous body that allows ventilation. This drum 1 is disposed below the output end of the laser beam L from the laser oscillator 10, and its rotation causes the photosensitive material sheet S
is moved in the sub-scanning direction to perform exposure.

The drum 1 is rotated by a drum drive motor 11 provided on the left side of the conveyor 3, and the output shaft of the motor 11 and the rotating shaft of the drum 1 are connected by a plurality of timing pulleys 12 and a timing belt 13. The drum 1 is configured to rotate in forward and reverse directions at a predetermined reduction ratio.

The supply mechanism 2 has first, second, and third guide members 21, 22, and 23 that guide the photosensitive sheet S, and the first guide member 21 is located on the magazine 4 side of the photosensitive sheet S. A third guide member 23 is located on the drum 1 side. Further, the second guide member 22 is provided with a gate mechanism 5 that opens and closes the passage of the second guide member 22 and applies a conveying force to the sensitive material sheet S.

This gate mechanism 5 is provided with a pair of feed rollers 31 and a pack tension roller 32 on the left and right sides, and
A gate 33 is provided to open and close the outlet of the second guide member 22.

In this case, the feed roller 31 and the upper roller of the pack tension roller 32 are both connected to the bracket plate 3.
4 is rotatably attached.

The bracket plate 34 is movable up and down, and its upward movement separates the upper rollers of the feed roller 31 and pack tension roller 32 from the lower rollers.
The downward movement brings the upper roller into rolling contact with the lower roller. The bracket plate 34 is biased by a spring 35 in a direction in which the rollers roll into contact with each other, and is moved upwardly by rotation of a lever 36 so that the upper roller is separated. On the other hand, the gate 33 is linked with the vertical movement of the bracket plate 34, and the upward movement of the bracket plate 34 causes the gate 33 to move up and down.
The outlet of the guide member 22 is closed, and the downward movement of the bracket plate 34 opens the outlet. Note that the feed roller 31 is rotated by being driven by a roller drive motor 37.

In such a gate mechanism 5, when the lever 36 is in the solid line state in the figure, the upper and lower rollers of the feed roller 31 and the pack tension roller 32 roll into contact and rotate due to the spring force of the spring 35, and the gate 33 opens the exit 9 of the second guide member 22, and the photosensitive material sheet S
In the stretched state by 2, a conveying force is applied by the feed roller 31 to move in the direction of the third guide member 23.

Further, when the lever 36 is in the state indicated by the chain line in the figure, the bracket plate 34 moves upward to separate the upper and lower rollers of both rollers 31 and 32, and the gate 33 closes the exit of the second guide member 22. It is closed, and particularly prevents feeding of the leading end of the photosensitive material sheet S during manual insertion, and also determines the position of the leading end.

Note that the first guide member 22 provided on the upstream side of the second guide member 22
Guide rollers 24 and 24 for guiding the photosensitive material sheet S are disposed on the guide member 21 . Further, a rotary cutter 6 is provided between the second guide member 22 and the third guide member 23. This cutter 6 cuts the photosensitive material sheet S into a predetermined length.

Further, the third guide member 23 is provided with a sensor 25 for detecting the leading and trailing ends of the photosensitive material sheet S. Based on the detection signal of this sensor 25, a roller drive motor 37 drives the photosensitive material sheet S as a reference. The position is detected, and the sensitive material sheet S abuts against the front end insertion plate 7 of the drum 1 at a position after being fed a predetermined step.

The sensitive material sheet S, which is transported by such a supply mechanism 2 and cut into a predetermined length by the cutter 5, is wound around the outer peripheral surface of the drum 1 by air adsorption. Members for holding or fixing the front end and rear end of S are provided, respectively. A leading end insertion plate 7 attached to the outer surface of the drum 1 holds the leading end of the sensitive material sheet S.

This tip insertion plate 7 has the third guide member 23 side facing toward the drum 1.
is bent in a direction away from the outer circumferential surface of the sheet, and this bent portion serves as an insertion opening for the light-sensitive material sheet S.

The leading end of the sensitive material sheet S is inserted into the leading end insertion plate 7 through this insertion opening and stopped at an internal stopper portion, thereby holding the leading end of the sensitive material sheet S on the drum 1 and positioning it on the drum 1. will be held.

11 On the other hand, a groove 14 is formed on the outer peripheral surface of the drum 1 in a portion close to the tip insertion plate 7, and a presser member 8 is provided in this groove 14. The holding member 8 includes a holding plate 41 and a shaft 42 to which the holding plate 41 is rotatably attached. When the shaft 42 rotates clockwise, the holding plate 41 rotates so as to come out of the groove 14. It faces onto the outer peripheral surface of the drum 1. Further, when the shaft 42 rotates in the opposite direction, the presser plate 41 rotates so as to enter into the groove 14. Through this operation, the presser plate 41 presses the rear end of the photosensitive material sheet S wound around the outer peripheral surface of the drum 1, and also presses the photosensitive material sheet S from the pressed state.
Open the rear end of.

In this embodiment, since the rotation of the presser member 8 is performed with the member 8 positioned at the end of the third guide member 23, interference between the presser plate 41 and the third guide member 23 is prevented. It is necessary to prevent this. For this reason, as shown in FIG.
At the time of rotation 1 2 , it smoothly passes through the front half of the third guide member 23 . The rotation of the pressing member 8 is performed in conjunction with the rotation of the drum 1 as will be described later, and a rotating means 9 is provided to perform this interlocking rotation.

The rotating means 9 is a rotating arm 51 attached to the drum 1.
A first kicker 52 and a second kicker 53 are arranged around the drum 1 so as to be opposed to each other by approximately 180 degrees with the drum 1 in between. The rotating arm 51 is rotatably attached to the side surface of the drum 1, and its tip portion projects outside the drum 1, and this projecting portion is subjected to the action of the first and second kickers 52 and 53. ing.

A gear 54 is attached to the rotary arm 51 so as to rotate integrally therewith. On the other hand, the shaft 4 of the presser plate 8
A gear 43 is also attached to the gear 2 so as to rotate together with the gear 43, and these gears 54 and 43 are connected via a gear train 55. In such a configuration, when the rotary arm 51 rotates, the presser plate 8 rotates, thereby pressing and releasing the rear end portion of the shrine sheet S. Note that a spring 56 is attached to the rotating arm 51 to constitute a click mechanism that maintains the stopped state of the rotating arm 51 at each rotation end point. 5
7.57 is a stopper pin that stops the rotation of the rotating arm 51.

Next, the first kicker 52 and the second kicker 5
3 are all rotated by drive members 58 and 59 such as rotary solenoids and motors. These drive members 58 and 59 rotate the rotary arm 51 by their rotation, the first kicker 52 rotates clockwise in the figure, and the second kicker 53 rotates counterclockwise in the figure. Rotate to.

The first kicker 52 rotates the rotary arm 51 counterclockwise by its clockwise rotation, and as a result, the presser part 8 rotates clockwise via the gear train 55, and the presser plate 8 rotates clockwise through the gear train 55. 41 faces the outer peripheral surface of the drum 1, and the rear end portion of the photosensitive material sheet S is fixed. On the other hand, the second
The kicker 1 4 53 rotates the rotary arm 51 clockwise by its counterclockwise rotation, which causes the presser member 8 to rotate counterclockwise and the presser plate 41 to be removed from the outer circumferential surface of the drum 1. Then, the pressure on the photosensitive material sheet S is released. Note that sensors 60 and 6 are installed near the first and second kickers 52 and 53 to recognize their predetermined positions.
0 is set. Further, in the vicinity of the second kicker 53, a pressure roller 15 is provided which rotates freely by rolling into contact with the outer peripheral surface of the drum 1 in conjunction with the rotation of the second kicker 53.

This pressing roller 15 is attached to the tip of a roller arm 17 which is urged by a spring 16 to rotate in the direction of the drum 1, and by rolling into contact with the outer peripheral surface of the drum, the presser at the rear end is pressed. The released photosensitive material sheet S is pressed to prevent it from sagging and falling. Thereby, the photosensitive material sheet S is smoothly guided onto the conveyor 3.

Reference numeral 18 denotes a stopper cam 1 5 that comes into contact with the roller arm 17 in order to release the rolling contact of the guide roller 15, and the guide roller 15 is moved against the drum 1 by driving the drive member 59 that rotates the second kicker 53. It is designed to rotate in the direction of contact and the direction of release.

Next, the operation of this embodiment will be explained with reference to FIGS. 2 to 12.

FIG. 2 shows the initial state and the home position where the sensitive material sheet S is wound around the drum 1. The photosensitive material sheet S is wound into a roll and stored in the magazine 4 so that the photosensitive surface is located on the inside, and is pulled out from the magazine 4 so as to face the winding direction opposite to this winding ( (See Figure 1). As a result, the photosensitive material sheet S is pulled out and sent to the supply mechanism 2 with the photosensitive surface facing upward.

FIG. 3 shows the state of the supply mechanism 2 before feeding out the sensitive material sheet S. Since the lever 36 is in the upright state, the bracket plate 34 is in the upward movement position, and the upper side of the feed roller 31 and the tension roller 32 are The lower roller is in the released state, and the exit of the second guide member 22 is blocked by the gate 33. In this state, pull out the sensitive sheet S and insert it so that it hits the gate 33,
When the lever 36 is tilted, the bracket plate 34 moves downward by the spring force of the spring 35, and as shown in FIG. 5, the feed roller 31 and the pack tension roller 32 roll into contact, and the gate 3B rotates. Then, the second guide member 22 is opened. Next, the photosensitive material sheet S is conveyed toward the drum 1.

In this state, the drum 1 is stopped at a position where the tip insertion plate 7 faces the end of the third guide member 23. When the leading edge of the sensitive material sheet 1-S is detected by the sensor 25, the roller drive motor 37 further moves the leading edge of the sensitive material sheet S by a predetermined amount of steps from this position, so that the leading edge of the sensitive material sheet S is inserted into the leading edge insertion plate 7. inserted. Then, the sensitive material sheet S whose leading end is inserted into the leading end insertion plate 7 is wound around the outer peripheral surface of the drum 1 while being air-adsorbed as the drum 1 rotates clockwise. Note that the drum 1 is rotated at a higher speed than the rotation during exposure, so that the abrasive grains 17 and S can be wound quickly.

FIG. 6 shows a state in which the photosensitive material sheet S reaches the cutting position due to the rotation of the drum 1 and is temporarily stopped, and the photosensitive material sheet S on the drum 1 is cut into the following photosensitive material sheet S by the operation of the cutter 6.
be separated from After this separation of the photosensitive material sheet S, the drum 1 continues to rotate, and the rear end side of the photosensitive material sheet S is also air-adsorbed onto the outer peripheral surface of the drum 1 in turn.

FIG. 7 shows a state in which the rear end of the photosensitive material sheet S is air-adsorbed on the outer peripheral surface of the drum 1, and the rotary arm 51 has reached just in front of the first kicker 52.

In this state, the drive member 58 of the kicker 52 operates, the first kicker 52 rotates counterclockwise, and this rotary arm 51 rotates counterclockwise, so that the rotational movement is transmitted to the gear 54 and the gear train. Gear 43 of presser member 8 via 55
The presser plate 41 of the presser member 8 rotates to come out of the groove 14 and faces the outer circumferential surface of the drum (the eighth drum).
(see figure).

At this time, the presser plate 41 rotates while the third guide 8 passes through the comb teeth of the guide member 23 and presses the photosensitive material sheet S instead of the third guide member 23 that is lightly pressing the photosensitive material sheet S. Press the rear end of drum 1 against drum 1.
Facing the outer circumferential surface of. That is, as the drum 1 rotates, the holding state of the rear end of the photosensitive material sheet S can be transferred from the third guide member to the presser plate 41, and the photosensitive material sheet S can be held down reliably. It has become so.

In the state shown in FIG. 7, the leading end of the sensitive material sheet S is inserted into and held by the leading end insertion plate 7, while the rear end is held by the presser plate 4.
1, the entire surface is tightly wrapped around the outer peripheral surface of the drum 1 by air adsorption. Therefore, even if the sensitive material sheet S has a tendency to curl, it is wound around the outer circumferential surface of the drum 1 in a good exposure-enabled state. In this case, the rotation of the rotating arm 51 is stopped by the stopper pin 57, but this rotationally stopped state is stably maintained by the spring force of the spring 56. Therefore, even if the drum 1 continues to rotate, the presser plate 41 of the presser member 8 can maintain contact with the outer peripheral surface of the drum 1, and the photosensitive material sheet S remains in contact with the drum 1 until the end of exposure. Good adhesion.

FIG. 9 shows the exposure start (home position) and exposure end state after the rear end of the photosensitive material sheet S has been pressed.

In the figure, a drum 1 is driven to rotate at a slow speed, and a dot image corresponding to an input image such as text, a photograph, or a picture is exposed on a photosensitive material sheet S by operating a laser beam L by a laser oscillator 10. . Such exposure is completed after the drum 1 has made one revolution or two or more revolutions as necessary, and stops at the position shown in FIG. From this state, the drum 1 is rotated at a relatively high speed in a counterclockwise direction, which is opposite to the previous rotation direction.

FIG. 10 shows this state of counterclockwise rotation, with the rotating arm 51 reaching just in front of the second kicker 53. At this time, the driving member 59 of the kicker 53 is moved to the second kicker.
53 in a counterclockwise direction.

FIGS. 11 and 12 show the rotational operation of the second kicker 53, which contacts the rotary arm 20 and the arm 51 and presses the arm 51. As a result, the rotating arm 51 rotates clockwise, and as described above,
The rotational movement is transmitted to the presser member 8, and the presser plate 41 of the member 8 rotates away from the outer peripheral surface of the drum 1 and enters the groove 14. As the presser plate 41 separates, the photosensitive material is At s, the presser at the rear end is released. On the other hand, the stopper cam 18 is attached to the drive member 59 of the second kicker 53.
The stop cam 18 rotates counterclockwise in conjunction with the rotation of the second kicker 53. Since the roller arm 17 is unlocked by this rotation of the stop cam 18, the roller arm 17 rotates clockwise. The pressure roller 15 at the tip of the roller arm 17 rolls into contact with the outer peripheral surface of the drum 1, and presses and holds the photosensitive material sheet S released from the pressing state at the rear end. Also,
Air suction is stopped to release the adhesive state of the photosensitive material sheet S.

FIG. 13 shows this state, in which the rear end of the photosensitive sheet S is prevented from sagging or falling by the suppression roller 15, and in this state, as the drum 1 rotates, the conveyor 3
It is guided upward and conveyed by the same conveyor 3 to the subsequent developing processing device. Note that the leading end of the sensitive material sheet S inserted into the leading end insertion plate 7 is caused by the counterclockwise rotation of the drum 1 and the releasability of the sensitive material sheet S itself, which is wound against the drum 1 in a direction opposite to the winding tendency. , is smoothly pulled out to the conveyor 3 from the insertion side. Further, after the photosensitive sheet S is carried out, the first kicker 52 and the second kicker 5 of the rotating member 9 are removed.
3 and the stopper cam 18 are returned to their initial states (FIG. 4).

In such a configuration, the leading end and the trailing end of the sensitive material sheet S are fixed to the drum 1, and the entire surface is brought into close contact with the outer peripheral surface of the drum 1 by air adsorption. Therefore, even if there is a tendency to curl, it is possible to supply the laser beam to the exposure position in a good exposure-enabled state without increasing the adsorption force of air adsorption.

Although the above embodiment has been applied to a plotter for preparing newspaper plates, the present invention can also be applied to other exposure devices as long as the sensitive material sheet is pulled out from a roll and wound around a drum. Can be applied.

〔Effect of the invention〕

As described above, according to the present invention, the leading end and the trailing end of a sensitive material sheet that is cut from a roll and wound around a drum are held and fixed to the outer peripheral surface of the drum, and the trailing end can be fixed and released. Since it is linked to the rotation of the drum, even if the sensitive material sheet has a tendency to curl, it can be wrapped around the drum so that its entire surface is in close contact with the drum, and it has the effect that it can be exposed in good condition.

[Brief explanation of drawings]

Fig. 1 is an overall schematic diagram showing an embodiment in which the present invention is applied to a plotter for preparing a newspaper plate, Fig. 2 is an overall configuration diagram of its main parts, and Fig. 3 shows the relationship between the guide member and the presser plate. The exploded perspective views and FIGS. 4 to 13 are configuration diagrams showing its operation. DESCRIPTION OF SYMBOLS 1... Drum, 2... Supply mechanism, 4... Magazine, 6... Cutter, 7... Tip insertion plate, 8... Holding member, 2 3 9... Rotating means, 11 ...Drum drive motor, 21
, 22.23... Guide member, 31... Feed roller, 32... Pack tension roller, 37...
Roller drive motor, 41... Holding plate, 42... Shaft l-, 51... Rotating arm, 52... First kicker 53... Second kicker 54... Gear, 5
8.59... Drive member, S... Sensitive material sheet 1., L.
...Laser light.

Claims (1)

[Claims] In an exposure device that exposes a photosensitive material sheet wound around the outer peripheral surface of a rotating drum by air adsorption by irradiating light, the photosensitive material sheet wound in a roll is attached to the drum. a cutter provided on the supply path of the photosensitive material sheet to cut the photosensitive material sheet into a predetermined length; and a cutter provided on the outer peripheral surface of the drum into which the leading end of the photosensitive material sheet is inserted. a front end insertion plate; a presser member that rotates freely toward and away from the outer peripheral surface of the drum to press and release the rear end of the photosensitive material sheet; and the presser member's movement toward and away from the drum rotates An exposure apparatus comprising: rotating means for rotating a presser member in conjunction with the rotation of the presser member.