JP2002120353A - Sheetlike member holding apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To certainly hold the end part of a sheetlike member without damaging the peripheral surface of a drum when the sheetlike member is held to the peripheral surface of the drum in a close contact state and to prevent the floatation or the like of the sheetlike member to the peripheral surface of the drum to prevent the lowering of image quality. SOLUTION: Since a clamp part 160 is rotated in a direction tensioning a printing plate 12 by the centrifugal force acting on a plate 150, the printing plate 12 adheres to the peripheral surface of the drum closely. Further, since the clamp part 160 is arranged to one end part in the width direction of the plate 150, the holding flange of the printing plate becomes short and an image recordable region becomes large.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for holding a sheet-like member used in a processing apparatus for treating the surface of a sheet-like member, wherein the sheet-like member is wound around a drum and held therearound. The present invention relates to a sheet-like member holding device for holding an end of a sheet-like member in close contact with a peripheral surface of a drum while rotating a shaft of the sheet-like member.

[0002]

2. Description of the Related Art In general, a photosensitive printing plate (hereinafter, referred to as "printing plate") having a photosensitive layer formed on a sheet-like support such as a thin aluminum plate is used for printing. As such a printing plate, a printing plate having different vertical and horizontal dimensions depending on the size of a printed material is used.

[0003] An image exposure apparatus for exposing a printing plate to an image is formed by winding the printing plate around a rotating drum and irradiating the printing plate with a light beam corresponding to image data while rotating the printing plate integrally with the rotating drum. In some cases, the printing plate is scanned and exposed.

When a printing plate is wound around a rotary drum, both ends of the printing plate along the circumferential direction of the rotary drum are held and fixed between the rotary drum and holding members such as chucks.

That is, a chuck corresponding to one end of the printing plate along the drum circumferential direction (for example, the end on the leading end side in the winding direction) is attached to a predetermined position of the rotary drum, and the other end of the printing plate is mounted. After the printing plate is wound around the rotating drum, the chuck corresponding to the end (here, the end of the rear end in the winding direction) is mounted at a position corresponding to the size of the printing plate.

Here, as a structure of a chuck to be attached to the rotary drum in accordance with the size of the printing plate, a fixation that can be inserted into an arbitrary position of a mounting groove formed in the circumferential surface of the rotary drum in a circumferential direction. Some have a top (post) (hereinafter referred to as a clamp). The fixed frame attached to the clamp can be moved to any of the mounting grooves, and can hold the edge of the printing plate at an appropriate position corresponding to printing plates of different sizes.

When exposing a printing plate wound around a rotating drum, the printing plate is brought into close contact with the peripheral surface of the rotating drum, and the printing plate is rotated at a high speed together with the rotating drum.

At this time, in order to prevent the end of the printing plate fixed by the chuck portion of the clamp from being lifted by the centrifugal force, the printing plate is located at a position opposite to the printing plate chuck position with the fixed frame interposed therebetween. A member is provided for promoting the holding force of the printing plate by the chuck portion. This member is a biasing member such as a spring, and has a structure in which the clamping force of the chuck is increased by the biasing force of the biasing member.

[0009]

However, in order to apply an urging force between the holding device such as the clamp or the like and the rotating drum, the urging member provided on the holding device is attached to the peripheral surface of the rotating drum. You need to make contact. For this reason, irregularities due to scratches and the like may be formed on the peripheral surface of the rotating drum.

When printing plates of different sizes are brought into close contact with the positions where the unevenness is formed, the printing plate is lifted due to the unevenness, and when the image is recorded by scanning a light beam, defocusing and image distortion occur. As a result, the image quality is adversely affected.

If the holding force of the holding member is weak, the adhesion of the printing plate to the rotating drum is reduced, which may cause a defocus or the like. This is due to the stiffness of the printing plate, and particularly occurs due to a shift in the compression direction of the printing plate at the end (holding position) of the printing plate in the circumferential direction of the rotating drum.

In view of the above facts, the present invention, when holding the sheet-like member in close contact with the peripheral surface of the drum, does not form any irregularities due to scratches or the like on the peripheral surface of the drum. It is an object of the present invention to provide a sheet-like member holding device capable of securely holding the sheet and preventing the image from being lowered with respect to the peripheral surface of the drum, thereby preventing deterioration in image quality.

[0013]

According to the first aspect of the present invention,
A holding device for a sheet-shaped member used in a processing apparatus for processing the surface of the sheet-shaped member, wherein the sheet-shaped member is held around a drum by rotating the drum while being held around the drum. A holding device for a sheet-like member for holding an end portion in close contact with the peripheral surface of the drum, and a support that can be attached to a predetermined position on the peripheral surface of the drum,
A rotating body that is rotatable by a predetermined angle around an axis parallel to the rotation axis of the drum with the support as a fulcrum, and a position at one end of the rotating body and opposed to an arrangement position of an end of the sheet-shaped member; In accordance with the rotation of the rotating body,
A clamp member movable to two positions of a clamping position and a clamping release position of the sheet-like member, and a direction in which the clamp member approaches the peripheral surface of the drum in a state where the support is fixed to the peripheral surface of the drum. A rotating member rotating means for rotating the rotating member; and a sheet-like member being tensioned in accordance with a centrifugal force generated by rotation of the drum in a state where the sheet-like member is held by the rotating member rotating means. And a clamp member rotating means capable of rotating the clamp member in a direction.

According to the first aspect of the present invention, the sheet-like member is disposed on the peripheral surface of the drum, and the holding device is disposed at the end in the winding direction. This holding device may be arranged in advance at a predetermined position on the peripheral surface of the drum, or stand by in a state of being separated from the drum, and after positioning the end of the sheet-shaped member, align it with this end. It may be arranged on the drum peripheral surface.

When the support is fixed at a predetermined position on the peripheral surface of the drum, the clamp member is moved in the direction of the drum peripheral surface by the rotation of the rotary body about the support by the rotary body rotation means. The end of the sheet-shaped member is held between the clamp member and the peripheral surface of the drum. Thereby, the end of the sheet-like member is held.

The sheet-like member is wound around the peripheral surface of the drum, and is held in close contact with the peripheral surface of the drum by holding both ends in the winding direction. In this case, the sheet-shaped member is prevented from being turned up due to the stiffness of the sheet-like member or the like, but may float in the middle of the sheet-shaped member due to relative movement (shift) with respect to the drum peripheral surface. This lifting is inconvenient in a process in which the distance to the surface of the sheet-shaped member is preferably uniform (for example, an image scanning recording process using a laser beam or the like).

Therefore, in the first aspect of the present invention, the clamp member is rotatable along the circumferential direction of the drum.
In this state, the clamp member is rotated in a direction in which the sheet-like member is tensioned by utilizing a centrifugal force generated according to the rotation of the drum. At this time, since the sheet member is made to follow the clamp member, even if the sheet member floats, it can be resolved by rotating the drum. That is, since the time during which the drum is rotating is the time to process the surface of the sheet-like member, it is possible to prevent at least the sheet-like member from floating during the processing.

According to a second aspect of the present invention, in the first aspect of the present invention, the rotating member rotating means is configured such that the clamp member is provided around the drum while the support is fixed to the drum. A rotating body biasing means capable of applying a biasing force to the rotating body in a direction approaching the surface, and when the drum rotates, centrifugal force generated by this rotation reduces the biasing force of the rotating body biasing means. It is characterized by promoting.

According to the second aspect of the present invention, the rotating body is rotated by the urging force of the rotating body urging means when the holding device is fixed to the drum, so that the clamp member approaches the drum. A sheet-like member can be held between the clamp member and the drum. Further, in this state, when the drum rotates, the rotating body rotates about the column by centrifugal force. Since this rotating direction is the same as the rotating direction of the rotating body by the rotating body urging means, during the rotation of the drum, both the urging force of the rotating body urging means and the centrifugal force are added. You. Therefore, the force for holding the sheet-like member can be increased.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the clamp member rotating means projects to both sides of the clamp member along a rotation axis of the drum. And a pair of short columnar protrusions provided at one end of the rotating body, and a pair of holding members respectively holding the protrusions so that the clamp member can rotate around the protrusions. Centrifugal force generated by rotation of the drum in a state in which the sheet-shaped member is held by the rotating body rotating means, the holding hole being constituted by a holding hole and a curved convex surface formed on the side of the rotating body facing the drum. When the clamp member is pressed by the rotating body by force,
The clamp member is rotated in a rotation direction for tensioning the sheet-shaped member.

According to the third aspect of the present invention, in a state where the curved convex surface of the clamp member is in contact with the sheet-shaped member, when the clamp member is pressed toward the peripheral surface of the drum by the rotation of the rotating body. Then, the clamp member rotates and the contact position of the clamp member to the sheet-like member moves on the curved convex surface. Since the direction of this rotation of the clamp member is the direction in which the sheet-like member is tensioned, a force for pulling the sheet-like member in the tension direction always acts during rotation of the drum, and it is possible to prevent floating or the like from occurring.

According to a fourth aspect of the present invention, in the third aspect of the present invention, the contact portion of the clamp member with the sheet member is larger than the rotation center of the convex portion. Is located on the side in the tension direction.

According to the fourth aspect of the present invention, the clamp member is formed by the pressing force acting on the convex portion of the clamp member toward the drum peripheral surface and the reaction force acting on the contact portion of the clamp member. Is applied to the clamp member. For this reason, the clamp member operates in the same manner as a so-called eccentric cam, and the clamp member rotates in a direction to tension the sheet-like member.

According to a fifth aspect of the present invention, in the first aspect of the present invention, a groove having a predetermined width is formed in the drum in a circumferential direction.
The width of the support may be wider or narrower than the width of the groove according to the rotational position of the shaft of the support, so that the support can be inserted into the groove, and can be prevented from falling off in the inserted state. It is characterized by:

According to the fifth aspect of the present invention, a circumferential groove is formed in the drum, and the column can be moved along the groove, so that the support is arranged at an arbitrary position on the circumferential surface of the drum. Can be. In addition, by inserting the column into the groove and retaining the column in this inserted state, the rotation of the rotating body using centrifugal force can be ensured.

According to a sixth aspect of the present invention, in the first aspect of the present invention, the sheet-like member is provided between the clamp member and the peripheral surface of the drum. In a non-clamping state, the apparatus further comprises positioning means for positioning the position of the clamp member in the rotation direction to the original position where the movable stroke amount of the sheet-like member in the tensioning direction is maximized.

In a state where the clamp member is not in contact with the sheet-like member, the rotational position of the clamp member is returned to the original position where the movable stroke amount becomes the maximum in order to gain a moving stroke after the contact. Need to be kept. According to the sixth aspect of the present invention, the positioning means can be positioned at the original position at least in a state where the clamp member does not press the sheet member.

According to a seventh aspect of the present invention, in the sixth aspect of the present invention, the positioning means is provided between the rotating body and the clamp member, and the rotation of the clamp member by the centrifugal force. It is a clamp member urging means for urging the clamp member in a direction to rotate in the opposite direction with an urging force weaker than the force.

According to the invention described in claim 7, according to claim 6,
Can have a simple structure.

The invention according to claim 8 is characterized in that the clamp member urging means is a tension leaf spring.

According to the eighth aspect of the present invention, the structure of the clamp member urging means can be significantly simplified.

According to a ninth aspect of the present invention, in any one of the first to eighth aspects of the present invention, the holding device is detachable from the drum. I have.

According to the ninth aspect of the present invention, for example,
When the leading end of the sheet-like member conveyed from the tangential direction of the drum reaches a predetermined position on the peripheral surface of the drum, the first holding device is moved closer to the drum and fixed, and the leading end of the sheet-like member in the carrying direction is fixed. Clamp. At this time, since there is no holding device for holding the rear end on the drum, there is no interference when the sheet-like members are sequentially wound around the drum. When the sheet-like member is wound around the peripheral surface of the drum,
The second holding device is made to correspond to the position corresponding to the rear end, and is fixed and clamped. Thereby, both ends of the sheet-like member can be clamped. Since the first holding device and the second holding device have different clamping directions at the front and rear ends of the sheet-shaped member, they are merely distinguished for convenience and need not have different structures.

[0034]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic configuration of an image exposure apparatus 10 applied to the present embodiment. The image exposure apparatus 10 has a rectangular thin plate shape (for example, having a thickness of 0.3 mm) formed of aluminum or the like as a sheet body.
Lithographic printing plate (hereinafter referred to as "printing plate 12") having a photosensitive layer formed on a support of
Is irradiated with a light beam modulated based on image data to perform scanning exposure. The printing plate 12 that has been subjected to image exposure by the image exposure device 10 is subjected to development processing and the like by an automatic developing device (not shown) or the like.

In the image exposure apparatus 10, a cassette loading section 18, a plate feeding and transporting section 20, a recording section 22, a discharge buffer section 24 and the like are provided in a machine frame 14. The cassette loading section 18 is disposed in the machine frame 14 at the lower right side in FIG. 1, and a plurality of cassettes 16 each accommodating a large number of printing plates 12 are inclined at a predetermined angle. Will be loaded.

The image exposure apparatus 10 can process a plurality of sizes of printing plates 12 having different vertical and horizontal dimensions.
The printing plate 12 of any size is accommodated in the cassette 16 with the photosensitive layer facing upward and one end positioned at a predetermined position. Further, the cassette loading section 18 is loaded with a plurality of cassettes 16 at a predetermined interval and one end of the printing plate 12 accommodated in each cassette 16 has a substantially constant height.

The plate feeding section 20 is arranged above the cassette loading section 18, and the recording section 22 is arranged at the lower center of the apparatus adjacent to the cassette loading section 18. The plate feeder 20 is provided with a pair of side plates 26 (only one is shown in FIG. 1).
8 and a single-wafer unit 30 are attached.

The reversing unit 28 includes a reversing roller 32 having a predetermined outer diameter, and a plurality of small rollers (in the present embodiment, as an example, the small roller 3 is provided around the reversing roller 32).
4A, 34B, 34C, and 34D). The small rollers 34 </ b> A to 34 </ b> D are arranged from the cassette loading section 18 to above the reversing roller 32 and to the recording section 22, and the endless transport belt 36 is wound around the small rollers 34 </ b> A to 34 </ b> D. As a result, the transport belt 36 is wound around the reversing roller 32 over about a half circumference between the small rollers 34A and 34D.

On the other hand, the single wafer unit 30 includes the cassette 16
A plurality of suction cups 38 for sucking the upper end portion of the printing plate 12 therein are provided.
The printing plate 12 is sucked to face the upper end of the printing plate 12 in the cassette 16 loaded in the cassette 8. Further, the sheet-feeding unit 30 pulls out the printing plate 12 from the cassette 16 by moving the suction cup 38 on which the printing plate 12 is sucked substantially upward, and moves the leading end of the drawn printing plate 12 to the reversing roller 32 and the transport belt. Insert between 36. In FIG. 1, the outline of the moving position of the suction cup 38 is indicated by a two-dot chain line.

In the reversing unit 28, the reversing roller 32 and the transport belt 36 rotate in the direction of pulling out the printing plate 12 from the cassette 16 (the direction of arrow A in FIG. 1). As a result, the printing plate 12 is sandwiched between the reversing roller 32 and the transport belt 36 and pulled out of the cassette 16, and is wound around the reversing roller 32, thereby being transported while being curved and inverted. The reversing roller 32
Is a dimension that does not cause the printing plate 12 to break or bend when the printing plate 12 is curved (for example, 100 mm).
mm or more).

As shown by the solid line and the two-dot chain line in FIG. 1, the side plate 26 moves horizontally in accordance with the position of the cassette 16 from which the printing plate 12 is taken out. Thus, the suction cup 38 of the sheet unit 30 is opposed to the printing plate 12 in the selected cassette 16.

The side plate 26 is provided with a guide 40 below the small roller 34D. The printing plate 12 inverted by the reversing roller 32 is moved between the reversing roller 32 and the transport belt 36 on the small roller 34D side. From this guide 40
Sent out to. In addition, above the recording unit 22,
A transport conveyor 42 is provided, and the reversing unit 28
The printing plate 12 sent out of the printer is guided to a conveyor 42 by a guide 40.

The guide 40 swings with the movement of the side plate 26 so that the guide direction of the printing plate 12 is always directed to the conveyor 42. Further, the small roller 34D of the recording unit 22 moves so as to change the sending direction of the printing plate 12 from the reversing unit 28 with the movement of the side plate 26, and the small roller 34C moves when the small roller 34D moves. Then, the transfer belt 36 is moved so as to apply a substantially constant tension to the transfer belt 36.
As a result, the printing plate 12 sent out from the reversing unit 28 is gently curved by the guide 40.

In the conveyor 42, a conveyor belt 48 is wound between a roller 44 adjacent below the plate feeding unit 20 and a roller 46 adjacent above the recording unit 22.
The roller 46 is inclined so that the roller 46 side faces downward.

As shown in FIGS. 1 and 2, a roller 50 is disposed on the conveyor 42 so as to face the roller 46, and the printing plate 12 sent onto the conveyor 42 is transported by the conveyor belt 48. Rollers 46, 5
0 pinched. In the recording unit 22, a rotary drum 54 and a recording head unit 56 are mounted on a gantry 52. A puncher 58 is provided above the rotating drum 54.
Is arranged.

As shown in FIG. 2, a mouth opening 60 is formed in the puncher 58 and
The printing plate 12 is sandwiched between the rollers 46 and 50, and the leading end of the printing plate 12 is inserted into and held by the mouth opening 60 of the puncher 58. The puncher 58 holds the printing plate 1
When the front end of the printing plate 12 is inserted, for example, a notch is formed at a predetermined position of the front end of the printing plate 12 for positioning.

When the notch is formed in the printing plate 12, the transport conveyor 42 moves the rollers 46 together with the transport belt 48.
50 is driven in reverse, and the leading end of the printing plate 12 is
8 is pulled out from the mouthpiece 60. Also, the conveyor 42
Is provided with a swinging means (not shown). The swinging means causes the roller 46 to move downward with the roller 44 as an axis so as to approach the rotating drum 54 of the recording unit 22 (see FIGS. 1 and 2). 2 is indicated by a two-dot chain line). This allows
The printing plate 12 on the conveyor belt 48 has a rotating drum 5
4 is conveyed on the conveyor belt 48 toward the rotating drum 54 toward a predetermined position on the outer peripheral surface of the roller 4.

The rotating drum 54 is driven by a driving means (not shown) to rotate the printing plate 1 in the mounting exposure direction of the printing plate 12 (the direction of arrow B in FIGS. 1 and 2) and in the opposite direction to the mounting exposure direction.
2 (in the direction of arrow C in FIGS. 1 and 2).

As shown in FIG. 2, the rotary drum 54 provided in the recording section 22 is provided with a tip chuck 62 at a predetermined position on the outer peripheral surface. Recording section 22
Then, when the printing plate 12 is mounted on the rotary drum 54, first, the front end chuck 62 stops the rotary drum 54 at a position (printing plate mounting position) facing the front end of the printing plate 12 fed by the conveyor 42. Let it.

The recording section 22 is provided with a mounting cam 64 facing the tip chuck 62 at the printing plate mounting position.
The printing plate 12 can be inserted between the tip chuck 62 and the peripheral surface of the rotating drum 54 by rotating the mounting cam 64 and pressing one end thereof. In the recording unit 22,
The tip of the printing plate 12 has a tip chuck 62 and a rotating drum 54.
By returning the mounting cam 64 to release the pressing on the tip chuck 62 in a state where the printing plate 12
Is held between the tip chuck 62 and the peripheral surface of the rotating drum 54. At this time, the printing plate 12
Is positioned with respect to the rotary drum 54 by inserting a positioning pin (not shown) projecting at a predetermined position on the peripheral surface of the rotary drum 54 into a notch formed by the puncher 58.

In the recording section 22, when the leading end of the printing plate 12 is fixed to the rotating drum 54, the rotating drum 54 is rotated in the mounting exposure direction. As a result, the printing plate 12 sent from the conveyor 42 is wound around the peripheral surface of the rotating drum 54.

In the vicinity of the peripheral surface of the rotary drum 54, the squeeze roller 6 is located downstream of the printing plate mounting position in the mounting exposure direction.
6 are arranged. The squeeze roller 66 moves toward the rotating drum 54 so that the rotating drum 54
The printing plate 12 to be wound around is pressed toward the rotating drum 54 to bring the printing plate 12 into close contact with the peripheral surface of the rotating drum 54.

The recording unit 22 includes a squeeze roller 6.
A rear end chuck attaching / detaching unit 68 is provided near the upstream side of the rotary drum 54 in the mounting exposure direction with respect to 6, and a removal cam 70 is provided near the downstream side in the mounting exposure direction. In the rear end chuck attaching / detaching unit 68, a rear end chuck 74 is attached to a front end of a shaft 72 protruding toward the rotating drum 54.

In the recording unit 22, the rear end of the printing plate 12 wound around the rotating drum 54 is connected to the rear end chuck attaching / detaching unit 6.
8, the shaft 72 is made to protrude, and the rear end chuck 74 is mounted at a predetermined position on the rotating drum 54. As a result, the rear end chuck 74 sandwiches and holds the rear end of the printing plate 12 with the rotating drum 54.

In the recording unit 22, when the rotating drum 54 holds the leading and trailing ends of the printing plate 12, the squeeze roller 66
Apart. After that, the recording unit 22
The recording head 56 emits a light beam modulated based on image data in synchronism with the rotation of the rotating drum 54 while rotating the drum 4 at a high speed at a predetermined rotation speed. Thus, the printing plate 12 is scanned and exposed based on the image data.

In the recording section 22, when the scanning exposure on the printing plate 12 is completed, the rotating drum 54 is moved to a position where the rear end chuck 74 holding the rear end of the printing plate 12 faces the rear end chuck attaching / detaching unit 68. The printing plate 12 is temporarily stopped, and the printing plate 12 is
Sandwich. The rear end chuck attaching / detaching unit 68 removes the rear end chuck 74 from the rotary drum 54 when the rear end chuck 74 faces and the rotation of the rotary drum 54 stops.
Thereby, the rear end of the printing plate 12 is opened.

In the recording section 22, when the rear end chuck 74 is removed from the rotary drum 54, the rotary drum 54 is
2. Rotate in the unloading direction. Thereby, the printing plate 12 is sent out from between the squeeze roller 66 and the rotating drum 54.

As shown in FIG. 1, the discharge buffer unit 2
4 is provided above the squeeze roller 66,
As the rotating drum 54 rotates in the direction in which the printing plate 12 is removed, the printing plate 12 is moved from the rear end side to the discharge buffer unit 2.
It is sent out to 4. The rotating drum 54 rotates in the direction in which the printing plate 12 is removed, and stops at the printing plate removal position where the tip chuck 62 faces the removal cam 70. In the recording unit 22, the tip cam 62 is pressed by rotating the removal cam 70 at this position, and the holding of the tip of the printing plate 12 between the tip chuck 62 and the rotary drum 54 is released. Thus, the printing plate 12 is removed from the rotating drum 54.

On the other hand, the discharge buffer section 24 is provided inside a discharge port 76 formed in the machine casing 14,
A discharge roller 78 is provided. Around the discharge roller 78, a plurality of small rollers (for example, small rollers 80A,
80B, 80C, 80D, 80E) are arranged,
An endless transport belt 82 is wound between these small rollers 80A to 80E. As a result, the discharge roller 78 has a 1/1 between the small roller 80A and the small roller 80E.
The transport belt 82 is wound around in a range of two to three quarters.

The small roller 80A protrudes toward the squeeze roller 66 of the recording unit 22, and the roller 84 is disposed to face the small roller 80A. The printing plate 12 sent from the recording unit 22 is guided between the small rollers 80A and the rollers 84, and is held between the small rollers 80A and the rollers 84.

In the discharge buffer section 24, the discharge rollers 78
Is rotated in the direction in which the printing plate 12 is pulled in (in the direction of arrow D), so that the printing plate 12 sandwiched between the small rollers 80A and the rollers 84 is guided between the discharge roller 78 and the transport belt 82 while being pulled out from the recording unit 22. , Discharge roller 78
, And wound around the discharge roller 78. At this time, in the discharge buffer unit 24, the leading end of the printing plate 12 (the rear end when sent from the recording unit 22) is sandwiched between the small rollers 80 </ b> A and the rollers 84, so that the printing plate 12 is wound around the discharge rollers 78. The plate 12 is held temporarily.

On the other hand, as shown by a two-dot chain line in FIG.
In the discharge buffer section 24, the small roller 80A and the roller 84
Moves to a position facing the outlet 76. At this time, the small roller 80A and the idle roller 84 rotate integrally, so that the leading end of the printing plate 12 is directed to the discharge port 76. The small roller 80B above the small roller 80A is
The conveyor belt 8 moves following the movement of the small roller 80A, and
2 is given a constant tension.

In the discharge buffer section 24, when the leading end of the printing plate 12 is directed to the discharge port 76, the discharge roller 78 is moved to the printing plate 12 by a processing device such as an automatic developing device arranged adjacent to the discharge port 76. The printing plate 12 is driven to rotate at a rotation speed corresponding to the conveyance speed of the printing plate 12 in the direction in which the printing plate 12 is sent out (the direction opposite to the direction of arrow D). As a result, the printing plate 12 is sent out from the outlet 76.

By the way, the printing plate 1 is
A tip chuck 62 for fixing the leading end of the printing plate 12 to a predetermined position on the peripheral surface of the rotating drum 54 when the drum 2 is wound around the rotating drum 54 is attached. The rear end chuck 74 is mounted.

As shown in FIG. 3, the tip chuck 62
Has a plate 150 formed in a strip shape with a predetermined length, and the plates 150 are arranged at predetermined intervals along the axial direction of the rotary drum 54. Also,
The rear end chuck 74 is a belt-shaped plate 15 having a predetermined length.
0, the plates 150 are mounted on the peripheral surface of the rotating drum 54 at predetermined intervals.

As shown in FIG. 4, the plate 150 is fixed to a plate main body 150M rotatably supported by a support 154 described later and screws on both sides of the plate main body 150M. A side-side engaging body 150S to be engaged, and a plate body 150M
In addition, the middle side engaging body 1 which is fixed by a screw at a predetermined distance (a distance corresponding to the length of the clamp section 160) from the side side engaging body 150S and is engaged with the clamp section 160
50I.

Although there is no difference in the functional structure between the front end chuck 62 and the rear end chuck 74, the direction of the plate 150 is different, and in this embodiment, the front end chuck 62 is And that the rear end chuck 74 is detachable from the rotary drum 54.

Hereinafter, the structures of the front chuck 62 and the rear chuck 74 will be described with reference to FIGS. A description will be given by taking a rear end chuck 74 provided with a mechanism detachable from the rotary drum 54 as an example. The difference between the structure of the front end chuck 62 and the rear end chuck 74 in the present embodiment is that the front end chuck 62 is fixed to the rotating drum 54 while the rear end chuck 74 is fixed to the rotating drum 54.
However, only the point that is removable.

The plate 150 of the trailing end chuck 74 has through holes 152 formed at substantially three intermediate positions in the width direction at three predetermined positions along the longitudinal direction thereof, and columns 154 are inserted. The support 154 has a rectangular block-shaped base 154A.
(Details will be described later), and a columnar supporting portion 154B erected on the upper surface of the base 154A. A cylindrical spacer 156 is inserted through the base of the support portion 154B so that the plate 150 can be supported at a predetermined height from the base 154A.

On the other hand, as shown in FIG. 3, a plurality of grooves 90 are formed at predetermined intervals on the peripheral surface of the rotary drum 54, and the rear end chuck 74 is attached to the base 15 of the support 154.
4A is attached to the rotating drum 54 in a state housed in the groove portion 90. In this housed state, the column 154 is rotatable in the drum circumferential direction around the contact point between the mounting groove 90 and the column 154.

Here, as shown in FIG. 6, the cross-sectional shape of the groove 90 is substantially trapezoidal, and the width W1 of the opening end is smaller than the width W2 of the bottom. On the other hand, the accommodation portion of the support 154 in the groove 90 is rectangular, and one dimension W3 of a pair of opposing sides is smaller than the width W1 of the opening of the groove 90, and the other dimension W4 is The width 90 of the bottom 90A of the groove 90 is smaller than the width W1 of the opening 90B. For this reason, when inserting the support | pillar 154 into the groove part 90, it becomes possible to insert by aligning the narrow side with the width direction of the groove part 90, and it is made to prevent from falling out by rotating about 90 degrees after insertion. Will be.

Here, the tip chuck 62 does not need to be attached or detached, and thus does not need to have the above-described structure. For example, it may be fixed by bolting or the like, but the same structure is applied. Then, it may be always in a fixed state.

When all the components are attached to the plate 150, the position of the center of gravity of the plate 150 is
(See FIGS. 8 and 10).

The plate 150 of the rear end chuck 74 has
The clamp portion 160 is rotatably engaged with one end in the width direction. The clamp portion 160 is formed of a rod-shaped holding member having a curved convex surface 160 </ b> A (see FIG. 5) that is in line contact with the printing plate 12 on the side facing the rotary drum 54.

The clamp unit 160 is provided with one plate 15
0, three round bar-shaped engaging projections 160P are provided on both sides of the clamp 160 in parallel with the rotation axis of the rotary drum 54. It is also provided to protrude on the side.

As shown in FIG. 5, the side engaging members 150
A side engaging portion 151 having an engaging hole 151 </ b> H parallel to the rotation axis of the rotating drum 54 is formed on the distal end side of S. As a result, the engaging projection 160P is engaged with the engaging hole 151.
H is pivotally engaged. Similarly, a middle engaging portion 149 with which the engaging projection 160P is rotatably engaged is formed on the distal end side of the middle engaging body 150I.

As a result, as shown in FIGS. 10 and 11, when the centrifugal force generated in the plate 150 causes a force (clamping force) to approach the drum peripheral surface to the clamp portion 160,
10 and 11, the clamp unit 160 is rotated counterclockwise (S direction), that is, in a direction to tension the printing plate 12.

A tension leaf spring 161 for exerting a tensile force is mounted between the right side surface of each clamp portion 160 in FIGS. 8 and 10 and the side surface of the plate body 150M. When the printing plate 12 is not clamped, the clamp 160 is urged by the urging force of the tension leaf spring 161 so as to be fully rotated clockwise in FIGS. 8 and 10 (hereinafter, this position). Is called in-situ).

Further, one end of a compression coil spring 180 is fixed to the lower surface of the right end in FIGS. 7 and 8 of the plate 150. The biasing direction of the compression coil spring 180 is a direction approaching the rotary drum 54, and a cover 182 that is in contact with the bottom 90 </ b> A of the groove 90 of the rotary drum 54 is attached to the other end.

Compression coil spring 18 with cover 182
When it is attached to the rotating drum 54, 0 is housed in a groove 90 provided in the rotating drum 54. That is, when the rear end chuck 74 approaches the rotary drum 54, the cover 182 first contacts the bottom surface of the groove 90, and when the rear end chuck 74 approaches further, the compression coil spring 180 is elastically deformed. The biasing force generated by the elastic deformation is a force for rotating the plate 150 with the support 154 as a fulcrum, thereby forming a pressing force by the clamp 160. When the compression coil spring 180 is elastically deformed, the cover 182 slides on the bottom surface of the groove portion 90. Since the sliding surface is an arc surface, the comparative friction coefficient is small and the sliding can be performed smoothly. It has become.

The operation of the present embodiment will be described below.

In the image exposure apparatus 10, image data to be exposed on the printing plate 12 is input, and the printing plate 12
When the size and the number of exposures are set and the start of image exposure is instructed, the image exposure processing on the printing plate 12 is started. Note that these processes may be performed by providing an operation panel in the image exposure apparatus 10 and instructing the same by operating a switch on the operation panel. A signal from an image processing apparatus or the like that outputs image data to the image exposure apparatus 10 may be used. May be used to instruct the image exposure apparatus 10 to start processing.

In the image exposure apparatus 10, when the start of the processing is instructed, the sheet unit 30 is moved together with the reversing unit 28 to a position corresponding to the cassette 16 accommodating the printing plate 12 of the designated size. The suction plate 38 sucks and removes the printing plate 12 in the corresponding cassette 16, and sends the printing plate 12 between the reversing roller 32 of the reversing unit 28 and the transport belt 36. As a result, the printing plate 12 is moved
2 and the conveyor belt 36 to be conveyed.
Sent to

The transport conveyor 42 first receives the printing plate 1
2 is inserted into the mouth opening 60 of the puncher 58. The puncher 58 forms a positioning notch at a predetermined position of the inserted printing plate 12. Conveyor 42
When the notch is formed in the printing plate 12, the printing plate 12 is pulled out from the mouth 60 of the puncher 58 and sent out toward the peripheral surface of the rotating drum 54.

In the recording section 22, when the leading end of the printing plate 12 is held on the rotating drum 54 by the leading end chuck 62, the printing plate 12 is wound around the rotating drum 54 while being squeezed by the squeeze roller 66, and the trailing end of the printing plate 12 is Is held on the rotating drum 54 by the rear end chuck 74. The procedure for this holding will be described later.

Thereafter, in the recording section 22, the rotating drum 54
The recording plate 56 irradiates the printing plate 12 with a light beam based on image data while rotating the printing plate 12 at a high speed.
Is exposed by scanning. At the time of this high-speed rotation, the tip chuck 6
The second and rear end chucks 74 exert a force for holding the printing plate 12 and a force for tensioning the printing plate 12 (floating prevention) by the action of centrifugal force due to the rotation of the rotary drum 54. This detailed operation will be described later together with the holding procedure.

When the scanning exposure of the printing plate 12 is completed, the tip chuck 62 is removed, and the printing plate 12 is sent to the discharge buffer unit 24.

In the discharge buffer section 24, after the printing plate 12 is nipped and conveyed by the small rollers 80A and the rollers 84 and wound around the discharge rollers 78, the small plates 80A and the rollers 84
Is discharged from the outlet 76 at a predetermined transport speed so as to face the outlet 76.

Next, the front end chuck 62 and the rear end chuck 7
The procedure for holding the printing plate 12 on the rotating drum 54 and tensioning the printing plate 12 and maintaining the printing plate 12 and maintaining the printing plate 12 will be described. In addition, since the front end chuck 62 and the rear end chuck 74 have the same operation, the rear end chuck 74 will be described below as an example. (Removal of the rear end chuck 74) First, when the rear end chuck 74 is mounted on the rotating drum 54, the base 15
The short side corresponds to the opening width direction of the groove 90 so that the groove 4A is accommodated in the groove 90 of the rotary drum 54. Thus, the base 154A is smoothly accommodated in the groove 90.
After the housing, the entire support 154 is rotated by approximately 90 °, so that the long side of the base 154A extends along the opening width direction of the groove 90, thereby preventing the base 154A from falling off.

Note that the rear end chuck 74 is
When removing the base 154A, the base 154A may be rotated by approximately 90 ° and pulled out. (Nipping (Clamping) of the Printing Plate 12) When the end of the printing plate 12 comes between the rotating drum 54 and the plate 150, the tip chuck 62 releases the rotation inhibition by the cam 64, and the compression coil spring 180 is released. Plate 15 with urging force
0 rotates with the support as a fulcrum. Due to this rotation, the clamp 160 moves in the circumferential direction of the rotary drum 54, so that the printing plate 12 can be sandwiched between the clamp 160 and the circumferential surface of the rotary drum 54.

Further, in the rear end chuck 74, the printing plate 12
Is mounted on the rotary drum 54 at the point in time when it comes to the predetermined position, the urging force of the compression coil spring 180 acts along with this mounting movement (the cover 182 of the compression coil spring 180 ), The plate 150 is gradually rotated with the support 154 as a fulcrum, and the printing plate 12 that has been positioned can be sandwiched between the peripheral surface of the rotary drum 54.

When the holding of the printing plate 12 by the leading end chuck 62 and the trailing end chuck 74 is completed, the rotating drum 54 starts rotating at a high speed for image recording.

[0093] By this rotation, the plate 150 is rotated about the column by the centrifugal force. At this time, the center of gravity of the plate 150 is
0, the rotation by the centrifugal force is in the same direction as the rotation by the urging force of the compression coil spring 180, and the rotation to the clamp 160 by the side engagement portion 151 and the middle engagement portion 149. The pressing force increases. Therefore, during the high-speed rotation of the rotary drum 54, that is, during the image recording, the clamping force of the front and rear ends of the printing plate 12 can be increased. (Tension of the printing plate 12) As shown in FIGS. 10 and 11,
The rotation of the rotating drum 54 at a high speed causes the plate 15 to rotate.
When a pressing force F for bringing the clamp 160 close to the drum peripheral surface is applied to the engagement convex part 160P from the plate body 150M by the centrifugal force generated at 0, the printing plate 12 is clamped on the drum peripheral surface by the clamp part 160. At the same time, the reaction force T from the drum peripheral surface is
Acts on 60A.

The action point P on the curved convex surface where the reaction force T acts is located at a position in the tensioning direction of the printing plate 12 more than the engaging convex portion 160P, that is, the engaging convex portion 160 on the paper surface of FIGS.
It is located to the right of the rotation center C of P.

Therefore, as shown in FIG. 11, the clamp 160 is turned counterclockwise (S direction) by the pressing force F and the reaction force T.
A turning moment is generated.

As described above, the rotational force for rotating the clamp portion 160 from the original position in the S direction is greater than the urging force (tensile force) of the tension plate spring 161 and, therefore, the clamp portion 160
Rotates in the S direction from the original position.

When the clamp unit 160 rotates from the original position, the printing plate 12 held between the clamp unit 160 and the rotary drum 54 is pulled in the tension direction.

Since this action occurs simultaneously at the front and rear ends of the printing plate 12, the intermediate portion of the printing plate 12 does not float on the peripheral surface of the rotary drum 54.

If the floating occurs, the laser beam will be deviated from the focal position of the laser beam at the time of recording an image on the surface of the printing plate 12, but in the present embodiment, the front and rear ends of the printing plate 12 are rotated by the clamp unit 160. The printing plate 12 is held between the drum 54 (the combined force of the compression coil spring 180 and the centrifugal force applied to the plate 150), and the printing plate 12 is tensioned, so that the intermediate portion of the printing plate 12 floats. Therefore, deterioration of image quality can be prevented.

As described above, in the present embodiment,
As a mechanism for applying a tension to the printing plate 12, apart from a holding mechanism of the printing plate 12 by the clamping unit 160, the clamping unit 1 is provided by utilizing centrifugal force acting on the plate 150.
60 is rotated. Therefore, the printing plate 12
The printing plate 12 can be clamped on the drum peripheral surface while preventing the floating or the like from occurring on the drum. Moreover, the plate 150
And the amount of protrusion from the rotating drum 54 can be reduced.

Further, the clamp part 160 is
Since it is arranged at the end of one end in the width direction of 0, the margin of the printing plate 12 is shortened, and the image recordable area can be increased.

In the present embodiment, the procedure for winding and holding the printing plate 12 around the rotating drum 54 is such that the front end chuck 62 is fixed and the rear end chuck 74 is detachable. Both may be removable or fixed, or the front chuck 62 may be removable, and the rear chuck 74 may be fixed. Further, the position of the chuck to be fixed is not limited.

[0103]

As described above, according to the present invention, when the sheet-shaped member is held in close contact with the peripheral surface of the drum, the end of the sheet-shaped member can be formed without forming irregularities due to scratches or the like on the peripheral surface of the drum. Has an excellent effect that the image quality can be reliably prevented, and the image quality can be prevented from being lowered with respect to the peripheral surface of the drum.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing an image exposure apparatus to which the present invention is applied.

FIG. 2 is a schematic configuration diagram illustrating a recording unit of the image exposure apparatus.

FIG. 3 is a schematic perspective view showing the arrangement of a front end chuck and a rear end chuck on a rotary drum.

FIG. 4 is a partially exploded perspective view of a rear end chuck which is one of the holding devices.

FIG. 5 is a partial perspective view showing that a clamp unit is rotatable.

FIG. 6 is a perspective view showing a dimensional relationship between a groove provided in the rotary drum and a support.

FIG. 7 is a side view taken along line 7-7 in FIG.

FIG. 8 is a sectional view taken along line 8-8 in FIG. 4;

FIG. 9 is a partially enlarged view of FIG. 7;

FIG. 10 is a cross-sectional view showing a state in which the clamp unit is rotated in a direction to tension the printing plate by a centrifugal force generated in the plate (corresponding to FIG. 8).

11 is a view taken along arrow 7- of FIG. 4 in the state shown in FIG. 10;
FIG. 10 is a partially enlarged side view of FIG. 7 (a view corresponding to FIG. 9).

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 Image exposure apparatus (processing apparatus) 12 Printing plate (sheet-shaped member) 54 Rotating drum (drum) 62 Tip chuck (holding device) 74 Rear end chuck (holding device) 149 Middle side engaging part (clamp member rotating means) 150 plate (rotating body) 151 side-side engaging portion (clamping member rotating means) 151H engaging hole (holding hole) 154 support 160 clamp portion (clamping member) 160A curved convex surface 160P engaging convex portion (convex portion) 161 tension Leaf spring (positioning means, clamp member biasing means) 180 Compression coil spring (rotating body rotating means, rotating body biasing means)

Claims (9)

[Claims] An apparatus for holding a sheet-like member used in a processing apparatus for treating the surface of a sheet-like member, wherein the sheet-like member is wound around a drum peripheral surface while rotating the drum while rotating. A holding device for a sheet-like member for holding an end portion of the sheet-like member in close contact with a peripheral surface of the drum, and a support that can be attached to a predetermined position on the peripheral surface of the drum; A rotating body rotatable by a predetermined angle around an axis parallel to the rotation axis of the drum; provided at a position of one end of the rotating body, and at a position facing an arrangement position of an end of the sheet-shaped member; A clamp member movable to two positions, a holding position and a holding release position of the sheet-like member, in accordance with the rotation of the rotating body; Is the dora A rotating body rotating means for rotating the rotating body in a direction approaching the peripheral surface of the sheet member; and And a clamp member rotating means capable of rotating the clamp member in a direction in which the sheet member is tensioned. 2. The rotating body rotating means may apply an urging force to the rotating body in a direction in which the clamp member approaches a peripheral surface of the drum when the support is fixed to the drum. 2. A holding member according to claim 1, wherein said rotating member biasing means is capable of biasing said rotating member, and a centrifugal force generated by said rotation promotes a biasing force of said rotating member biasing means when said drum rotates. apparatus. 3. The clamp member rotating means includes a pair of short columnar protrusions provided on both sides of the clamp member along a rotation axis of the drum, and one end of the rotating body. A pair of holding holes formed and respectively holding the convex portions so that the clamp member is rotatable around the convex portions; and a curved convex surface formed on a side of the rotating body facing the drum. When the clamp member is pressed by the rotating body by the centrifugal force generated by the rotation of the drum in a state where the sheet-shaped member is held by the rotating body rotating means, the sheet-shaped member is tensioned. 3. The sheet-like member holding device according to claim 1, wherein the clamp member rotates in a rotating direction in which the clamp member rotates. 4. The sheet-like member according to claim 1, wherein a contact portion of the clamp member with the sheet-like member is located on a side of the sheet-like member in a tension direction with respect to a center of rotation of the projection. 4. The holding device for a sheet-like member according to 3. 5. A groove having a predetermined width is formed in the drum in a circumferential direction, and the width of the post is wider or narrower than the width of the groove in accordance with an axial rotation position of the post. 5. The sheet-like member holding device according to claim 1, wherein the support member can be inserted into the groove, and can be prevented from falling off in the inserted state. 6. 6. A stroke capable of moving the position of the clamp member in the direction of tension of the sheet member in a state in which the sheet member is not sandwiched between the clamp member and the peripheral surface of the drum. The sheet-like member holding device according to any one of claims 1 to 5, further comprising a positioning unit that positions the original position at which the amount is maximum. 7. A direction in which the positioning means is provided between the rotating body and the clamp member, and rotates the clamp member in the opposite direction with a biasing force smaller than a rotational force of the clamp member due to the centrifugal force. 7. The sheet-like member holding device according to claim 6, wherein the holding member is a clamp member urging means. 8. The sheet-like member holding device according to claim 7, wherein said clamp member urging means is a tension leaf spring. 9. A sheet-like member holding apparatus according to claim 1, wherein said sheet-like member holding apparatus is detachable from said drum.