JP2001138472A - Platemaking apparatus and platemaking printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a platemaking apparatus having good image dimension reproducibility without wrinkle or the like in a master at plate-making even by using, of course, a conventional master, a master having a thin thickness of a porous support or a master having no porous support. SOLUTION: A master holding angle varying means 50 has a constitution and a function of changing a master holding angle θa formed between a half linear line connecting the center Nc of a nip between a thermal head 11 and a platen roller 10 to the axial center 10b of the roller 10 as seen from the axial direction of the roller 10 and a half linear line connecting a master contact boundary Mb contacted with the outer peripheral surface of the roller 10 at a downstream side of a master conveying direction X from the center Nc of the nip by a master 8 to the axial center 10b of the roller 10 as seen from the axial direction of the roller 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a plate making apparatus and a plate making apparatus.

[0002]

2. Description of the Related Art Conventionally, stencil printing using a digital thermosensitive stencil printing apparatus has been known as a simpler printing method. This is achieved by pressing a thermal head, in which fine heating elements are arranged in a line, against a platen roller via a heat-sensitive master (hereinafter simply referred to as a “master”), and energizing the heating elements of the thermal head in a pulsed manner to generate heat. After the master is conveyed by the platen roller, it is heated and melt-punched and made according to the image information. The printing paper is continuously pressed by pressing means such as a press roller, ink is supplied by an ink supply member provided inside the plate cylinder, and ink is passed through the opening part of the plate cylinder and the perforated part of the master. A print image is formed by transferring the image to printing paper. The master used in such a conventional stencil printing machine includes a very thin thermoplastic resin film such as polyester (hereinafter, simply referred to as "film") and a paper support such as Japanese paper or synthetic fiber as an ink-permeable porous support. Alternatively, it has a laminate structure in which a mixture of Japanese paper and synthetic fiber is laminated, and ink oozing out from the fiber portion of the porous support and the perforated portion of the film is transferred to printing paper to perform stencil printing. .

[0003] Therefore, the passage of ink is hindered in a portion called "dama" where fibers used for the porous support of the master are complicatedly entangled and hardened, or in a portion where thick fibers cross the perforated portion of the film. The ink does not transfer to the printing paper, and a fiber pattern appears, especially in a solid portion, or characters or fine lines are blurred or cut off. There was a defect. Therefore, the thickness of a porous support such as Japanese paper, which is the basis of the fiber, is reduced, or printing is performed using a master substantially made of only a thermoplastic resin film from which the porous support itself has been removed. Attempts have been made to reduce the number of fibers. The thickness of a conventional master is usually about 40 to 50 μm, whereas the thickness of a master substantially consisting of only a thermoplastic resin film is extremely thin, about 2 to 7 μm. Has become.

[0004]

However, the strength of the master is greatly reduced by reducing the thickness of the porous support of the master or by removing the porous support itself. In the conventional master, the strength was secured by Japanese paper etc. as a porous support, so that master expansion during plate making and deformation of the master due to shrinkage of the film were prevented, but the thickness of the porous support was When the thickness is thin or there is no porous support at all, the strength is greatly reduced and the master elongation and the film shrinkage are likely to be uneven, which causes wrinkles at the time of master making,
There has been a problem in that when the master is wound around the plate cylinder, the wrinkles of the master are likely to occur due to the deformation of the master. The film surface of the master is subjected to anti-sticking treatment by applying an anti-stick agent or the like to reduce the contact resistance generated between the master conveyed by the platen roller and the thermal head during plate making to reduce the master resistance. Although the feeding of the master is not uneven, the part where the film is heated and melted and the perforation and plate making is performed, because the resin part is exposed and the effect of the stick preventive agent is reduced, The contact resistance increases, and the transport delay of the master is likely to occur, albeit slightly. If the transfer distance of the master is different due to such a transfer delay of the master, the reproducibility of the image dimension is deteriorated, and the transfer delay of the plate making portion tends to loosen the master on the platen roller on the upstream side in the master transfer direction. However, there is a problem that the slack of the master is crushed by the platen roller and wrinkles are generated.

In the case of a master in which the film is prevented from being deformed by a porous support like a conventional master, the master is transported by a transport member such as a transport roller pair provided downstream of the platen roller in the master transport direction. By pulling the master to the downstream side in the transport direction and applying front tension, it is possible to compensate for the transport delay of the master. Since the strength of the perforated / plate-made portion is significantly lower than that of the non-perforated portion, when the front tension is applied, the perforated portion having reduced strength easily extends, thereby adding a predetermined front tension to the master. Can no longer satisfy the plate making length, or the master may shrink and deform. Ku made or, or wound wrinkles due to the deformation of the master when wound around the plate cylinder there is a problem that becomes more likely to occur. The master made between the platen roller and the thermal head is in a state where the strength of the portion is reduced, but in a case where the master in the portion is subsequently conveyed in a state of approaching the thermal head. However, if plate making is continued continuously at the beginning, there is also a problem that the plate portion of the plate made by the plate making is easily deformed due to the heat storage of the thermal head and the like. .

Accordingly, the present invention has been made to solve the above-mentioned problems by using not only a conventional master but also a master having a small thickness of a porous support or, for example, a master substantially consisting only of a thermoplastic resin film. Even when a master without a porous support is used, no wrinkles or the like are generated during plate making. It is an object of the present invention to provide a plate-making printing apparatus having good image size reproducibility.

[0007]

According to the first aspect of the present invention,
A plate making apparatus comprising: a thermal head for heating and making a master to be fed out according to image information; and a rotatable platen roller for moving the master downstream in the master transport direction while pressing the master against the thermal head. When viewed from the axial direction of the roller, a half line connecting the center of the nip between the thermal head and the platen roller and the axial center of the platen roller, and when viewed from the axial direction of the platen roller, the master is the center of the nip. A master hugging angle varying means for changing a master hugging angle between a master contact boundary contacting the outer peripheral surface of the platen roller and a half line connecting the center of the platen roller on the downstream side in the master transport direction. It is characterized by.

According to a second aspect of the present invention, in the plate making apparatus according to the first aspect, the master holding angle varying means is disposed downstream of the platen roller in the master transport direction, and downstream of the master transport direction. And a displacement member drive means for displacing the displacement member in a direction in which the master hugging angle is changed by contacting the master and changing the master hugging angle. According to a third aspect of the present invention, there is provided a plate making apparatus according to the second aspect,
The displacement member is a rotatable roller.

The invention according to claim 4 is the invention according to claim 2 or 3.
In the plate making apparatus described above, a transport roller disposed downstream of the displacement member in the master transport direction and configured to move a master downstream of the master transport direction, transport roller driving means for driving the transport roller, A torque limiter is provided between a transport roller and the transport roller driving means and applies a front tension to a master between the center of the nip portion and the transport roller. Here, as a specific example of the transport roller, a transport roller pair used in an embodiment described later is preferable from the viewpoint that the front tension is stably applied over the master width direction. However, the present invention is not limited thereto, and may be, for example, a combination of one transport roller for pressing a master against a plate-like member and the above-mentioned plate-like member. As a specific example of the transport roller driving unit, a stepping motor used in an embodiment described later is preferable from the viewpoint that the rotation speed control is performed stably and easily, but such an advantage may not be desired. However, the present invention is not limited to this, and may be a control DC motor or the like.

As a specific example of the torque limiter, a powder type or hysteresis type electromagnetic clutch, which is used for relatively small tension control, in that a predetermined front tension is applied by electrically varying transmission torque. It is preferably used. If such advantages do not have to be desired, the present invention is not limited to this, and may be, for example, a friction type electromagnetic clutch or a mechanical type torque limiter.

According to a fifth aspect of the present invention, in the plate making apparatus according to the fourth aspect, a master storage means for storing the master so that the master can be fed out, and a back tension is applied to the master between the master storage means and the platen roller. And a back-tension applying means for making the back tension larger than the front tension. Here, the back tension applying means is disposed between the master storage means and the platen roller, and is configured to be rotatable in contact with the master on the upstream side in the master transport direction, and to rotate the tension roller. And a braking means for braking the vehicle. As a specific example of the tension roller, a pair of tension roller pairs used in an embodiment to be described later is preferable from the viewpoint of stably applying the back tension in the master width direction. If not required, the present invention is not limited to this. For example, a combination of one tension roller for pressing the master against the plate member and the plate member may be used. As a specific example of the braking means, it is used for relatively small tension control in terms of controlling the braking force by electrically varying the transmission torque or variably controlling the braking force according to the type of master. A powder type or hysteresis type electromagnetic brake as described above is preferably used. If such an advantage is not required, the present invention is not limited to this, and may be, for example, a friction type electromagnetic brake or a mechanical brake means.

[0012] The invention according to claim 6 is the invention according to claims 1 to 5.
In the plate making apparatus according to any one of the above, a characteristic value detecting means for detecting a characteristic value of a master expansion / contraction-related factor affecting expansion / contraction of a master plate making dimension during plate making, and a signal from the characteristic value detecting means And control means for controlling the master holding angle varying means so as to change the master holding angle based on

According to a seventh aspect of the present invention, in the plate making apparatus of the sixth aspect, the characteristic value of the master expansion / contraction-related factor is:
The characteristic value detecting means is a plate making image amount formed on the master, and the characteristic value detecting means comprises an image amount detecting means for detecting the plate making image amount. According to an eighth aspect of the present invention, in the plate making apparatus according to the sixth aspect, the characteristic value of the master expansion / contraction related factor is at least one of an internal temperature and an external temperature of the plate making apparatus main body. The detecting means comprises temperature detecting means for detecting at least one of the temperatures.

According to a ninth aspect of the present invention, in the plate making apparatus of the sixth aspect, the characteristic value of the master expansion / contraction-related factor is:
The characteristic value detecting means is at least one of humidity inside and outside the plate making device main body, and the characteristic value detecting means comprises humidity detecting means for detecting the at least one humidity. The invention according to claim 10 is the invention according to claim 6
In the plate making apparatus described above, the characteristic value of the master expansion / contraction-related factor is a temperature of the thermal head, and the characteristic value detecting means includes a thermal head temperature detecting means for detecting a temperature of the thermal head. I do.

According to an eleventh aspect of the present invention, in the plate-making apparatus according to any one of the sixth to tenth aspects, the control means is configured to perform the control based on each signal from at least two or more of the characteristic value detecting means. And controlling the master holding angle changing means so as to change the master holding angle.

According to a twelfth aspect of the present invention, in the plate making apparatus according to any one of the first to eleventh aspects, the master downstream of the platen roller in the master transport direction or the master that has been subjected to the plate making is subjected to the thermal processing. The paper is transported in a direction away from the head.

According to a thirteenth aspect of the present invention, there is provided a plate cylinder having the above-described plate-making device according to any one of the first to twelfth aspects, and a plate cylinder on which a master made by the plate-making device is wound. Having ink supply means for supplying ink to the upper master,
A plate-making printing apparatus characterized in that printing is performed on a printing sheet by pressing the printing sheet against a master on the plate cylinder.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention including embodiments with reference to the drawings (hereinafter, simply referred to as "embodiments").
Will be described. In the embodiments and the like, members, components, and the like having the same function, shape, and the like are denoted by the same reference numerals, and description thereof will be omitted as much as possible. In the figures, members and components that are configured as a pair and need not be specifically distinguished and described are described in order to simplify the description.
By appropriately describing one of them, the description will be replaced. For the sake of simplicity of the drawings and the description, even if the members and the components are to be shown in the drawings, the members and the components that do not need to be specifically described in the drawings may be omitted as appropriate.

An embodiment will be described with reference to FIGS. In FIG. 1, reference numeral 70 denotes a plate making apparatus, and reference numeral 8 denotes a plate making apparatus.
Reference numeral 0 denotes a plate-making printing apparatus provided with the plate-making apparatus 70. As shown in FIGS. 1 to 3, the plate making device 70 includes a master support member 8c serving as a master storage unit that stores the master 8 so as to be able to be fed in the master transport direction X, and heats the fed master 8 according to image information. A thermal head 11 for making a plate, a platen roller 10 for moving and transporting the master 8 downstream in the master transport direction X while pressing the master 8 against the thermal head 11, and a master holding angle θa for changing a master holding angle θa described later in detail. The variable means 50, the back tension applying means 36 for applying the back tension F1 to the master 8 upstream of the platen roller 10 in the master transport direction X, and the master 8 downstream of the platen roller 10 in the master transport direction X A front tension applying means 38 for applying the front tension F2.

The master 8 has a continuous sheet shape and is wound around a synthetic resin roll core 8b.
Is formed. The roll core 8b protrudes from both end surfaces of the master roll 8a and is formed longer than the width of the master 8. In the master roll 8a, the roll cores 8b on both ends are rotatably supported in a counterclockwise direction by a master support member 8c, and are detachable from the master support member 8c. The master support members 8c at both ends are arranged on the left and right sides along the master transport direction X in the plate making apparatus 70, and shown in FIG.
9b. Therefore, the master 8
It is stored so that it can be fed out in the master transport direction X from the master roll 8a by the master support member 8c. The master 8 is substantially composed of, for example, only a thermoplastic resin film having a thickness of 2 to 7 μm. Here, the master substantially consisting of only the thermoplastic resin film, other than the master is made of only the thermoplastic resin film, the master contains a trace component such as an antistatic agent in the thermoplastic resin film,
Further, it includes a thermoplastic resin film in which one or more thin film layers such as an overcoat layer are formed on both principal surfaces, that is, at least one of the front surface and the back surface. As a film material of the master 8, for example, a polyester terephthalate (PET) -based material is used.

The back tension applying means 36 is disposed between the master supporting member 8c and the platen roller 10,
A pair of upper and lower rotatable tension rollers 9b, 9a rotatably contacting and nipping the master 8 upstream of the platen roller 10 in the master transport direction X, and an electromagnetic as braking means for braking the rotation of the tension roller lower 9a. Brake 3
7

The outer periphery of the lower tension roller 9a is made of a conductive elastic material and is formed integrally with a metal shaft. The lower side of the tension roller 9a is a plate making side plate pair 29a, 2
9b (shown only in FIG. 3) is rotatably supported, so that it is rotatable counterclockwise. As the electromagnetic brake 37, a powder type electromagnetic brake provided at the shaft end of the lower tension roller 9a is preferably used. The powder type electromagnetic brake 37 applies a braking force set in advance to the lower tension roller 9a via the shaft according to the type of the master, so that the master 8 on the upstream side of the platen roller 10 in the master transport direction X is moved. ,
That is, it has a function of giving a back tension F1 of a preset size to the master 8 between the platen roller 10 and the tension roller upper / lower pair 9b, 9a. More specifically, the back tension F1 having a size set in advance according to the type of the master is controlled by a command from the control device 65 shown in FIG.
7, the transmission torque is variably controlled substantially in proportion to the excitation current, so that a braking force (braking force) of a magnitude set in advance according to the type of master is obtained. Is applied to the lower tension roller 9a via the shaft. The electromagnetic brake 37 is not limited to a powder-type electromagnetic brake, and a hysteresis-type electromagnetic brake, for example, is preferably used for relatively small tension control.

The upper tension roller 9b is made of metal, and has a shaft portion integrally formed. The upper end of the tension roller 9b is rotatable clockwise because both ends of the shaft are rotatably supported by the pair of plate making side plates 29a and 29b shown only in FIG.

The back tension F1 applied to the master 8 between the platen roller 10 and the tension roller upper / lower pair 9b, 9a is the same as the thermal head 1 during plate making.
Due to the conveyance and contact resistance of the pierced portion of the master 8 in the nip portion N between the platen roller 1 and the platen roller 10, the non-perforated portion is quickly fed to cause loosening of the master 8,
The platen roller 10 is used to cause a slight slip between the master 8 and the non-perforated portion of the master 8 so that the master 8 in the non-perforated portion is not pulled by the transfer rollers 12a and 12b to be described later. The large and high back tension F1 is set so as not to occur. The tension roller upper and lower pairs 9b and 9a are pressed against each other by being given an appropriate pressing force by a biasing means such as a spring. The upper and lower pairs of tension rollers 9b and 9a
In the case of the conveyance at the time of the initial setting, the driving force is transmitted from a driving source (not shown) to carry the rotation. The upper and lower pairs 9b and 9a of the tension roller are controlled by a control device 65 described later when the master 8 is quickly sent out of the plate making area, when a portion having no image is skipped during the plate making, and the master 8 is quickly fed, or as described later. Roller 2
7 is displaced in the upward direction U, and the master holding angle θa shown in FIG.
In order to reduce the load on the master 8, for example, the braking force is not reduced, and the back tension is not applied.

The platen roller 10 is disposed on the downstream side in the master transport direction X adjacent to the tension roller upper / lower pair 9b, 9a, and is formed integrally with the platen roller shaft 10a via a metal core. Have been. Platen roller 10
Is made of a high molecular elastic material, and is covered with a silicone rubber layer having good non-adhesion to the master 8, heat resistance, conductivity and good compression set.

The specifications of the platen roller 10 will be described in more concrete terms. For example, as disclosed in Japanese Patent Application Laid-Open No. Hei 8-1901 proposed by the present applicant, a polymer elastic body of the platen roller 10 is used. A silicone rubber layer having a hardness (Hs) of JIS hardness A45 to 70 degrees is preferably used. The reason for this is disclosed in JP-A-8-19.
No. 01, paragraphs (0012), (003)
This is because the advantages and the like described in 6) to (0038) can be obtained. Further, as described later, in order to obtain the advantage of suppressing the heat shrinkage of the heat-melted perforated portion of the master 8 under the condition where an appropriate frictional resistance is generated at the master holding angle θa, the material of the film is changed. For the master 8 made of polyester terephthalate, the platen roller 1
0 of the outer surface of the silicone rubber layer is, for example, μ
= 0.5 to 1.5 are preferably used.

The platen roller 10 has a pair of plate making side plates 29a, 29b shown in FIG.
, So that it can rotate clockwise. The platen roller 10 is connected to a first stepping motor 35 as platen roller driving means via a rotation transmitting member (not shown) such as a timing belt and a gear, and is thereby driven to rotate clockwise. As described above, the platen roller 10
Is rotated clockwise by the first stepping motor 35, whereby the master 8 is pulled out from the master roll 8a while receiving the back tension F1 by the tension roller upper and lower pairs 9b and 9a.

The thermal head 11 is a platen roller 1
The platen roller 10 is provided so as to extend in parallel with the platen roller shaft 10a, and can be freely moved toward and away from the platen roller 10 via the master 8 by a contacting / separating mechanism having a cam, a spring member, and the like (not shown). The thermal head 11 is urged by the spring member in a direction in which the thermal head 11 comes into contact with the platen roller 10. In the main scanning direction of the thermal head 11, a large number of heating elements (not shown) are disposed at a position where the heating element contacts the platen roller 10 via the master 8. The thermal head 11 selectively heats the heating element based on a digital image signal processed and transmitted by an A / D converter and a plate making control device (both not shown) of a document reading device (not shown), The master 8 has a well-known function as a plate making means for selectively heating and melting perforation and plate making.

The front tension applying means 38 is disposed on the downstream side in the master transport direction X adjacent to the platen roller 10 and is disposed in the master transport direction X with respect to the platen roller 10.
A pair of upper and lower transport rollers 12a and 12b serving as rotatable transport rollers for moving and transporting the master 8 downstream in the master transport direction X by contacting and nipping the master 8 on the downstream side and the upper transport roller 12a A first stepping motor 35 as a transport roller driving means for rotating the roller at a peripheral speed (transport speed) higher than the peripheral speed (transport speed) of the platen roller 10, and between the transport roller 12 a and the first stepping motor 35. A first electromagnetic clutch 33 provided as a torque limiter for adjusting the front tension F2 to a preset value. The conveying roller 12a is connected to a first stepping motor 35 via a rotation transmission member (not shown) such as a plurality of gears,
Thereby, it is driven to rotate clockwise. The drive system around the platen roller 10 and the transport roller 12a via the first stepping motor 35 is the same as the rotation transmission mechanism shown in FIG. 2 of Japanese Patent Application Laid-Open No. 11-77949 proposed by the present applicant, for example. The mechanism is adopted.

The outer peripheral portion of each of the transport roller middle pairs 12a and 12b is made of silicone rubber, and is formed integrally with a metal shaft. The transport roller middle pair 12a, 12b
An appropriate pressing force is applied by an urging means such as a spring, and they are provided in pressure contact with each other. Both ends of the respective shafts are rotatably supported by the pair of plate making side plates 29a and 29b, so that the shafts oppose each other. It is freely rotatable. As the first electromagnetic clutch 33, a powder-type electromagnetic clutch provided at the shaft end of the transport roller 12a is preferably used.
First electromagnetic clutch 33 composed of a powder type electromagnetic clutch
Applies a predetermined front tension F2 such that the master 8 is not forcibly dragged out of the nip portion N between the platen roller 10 and the thermal head 11.
To the master 8 between the transport roller middle pair 12a and 12b. The front tension F2 is set smaller than the back tension F1 described above, in other words, the back tension F1 is set larger than the front tension F2. The size of the front tension F2 is, for example, in a state where the connection with the first stepping motor 35 is released, and
This is such that the platen roller 10 in a stationary state is not rotated. In a practical example, F2 = 0.3k
gf ≒ 2.94N is set. More specifically, the front tension F having a predetermined size is set.
2 is applied to the master 8 by changing the exciting current flowing through the exciting coil of the powder-type electromagnetic clutch according to a command from the control device 65 shown in FIG. It is done by being controlled. The first electromagnetic clutch 33 is not limited to the powder type electromagnetic clutch, but is used for controlling a relatively small tension.
For example, a hysteresis type electromagnetic clutch is preferably used.

A rotatable angle roller 27 constituting a master embedment angle varying means 50 is provided on a master transport path between the transport roller middle pair 12a, 12b and the platen roller 10.
Is arranged. The master holding angle changing means 50 is shown in FIG.
As seen from the axial direction of the platen roller 10,
When viewed from the axial direction of the platen roller 10 and the half line connecting the nip center Nc between the thermal head 11 and the platen roller 10 and the axial center 10b of the platen roller 10, the master 8 moves from the nip center Nc to the master transport direction X. It has a configuration / function of changing a master holding angle θa formed by a master contact boundary Mb that is in contact with the outer peripheral surface of the platen roller 10 on the downstream side and a half line connecting the axis center 10b of the platen roller 10.

The master hugging angle changing means 50 is disposed downstream of the platen roller 10 in the master conveyance direction X and contacts the master 8 downstream of the master conveyance direction X to change the master hugging angle θa (this embodiment). In the embodiment, an angle roller 27 as a displacement member capable of being displaced in the upward direction U and the downward direction D), and plate making for guiding the angle roller shafts 27a at both ends of the angle roller 27 in the upward direction U and the downward direction D. A guide groove 29c is formed in each of the side plate pairs 29a and 29b, and a U-shaped groove 51u that always engages and supports the angle roller shaft 27a at one end.
a U-shaped groove 51u that always engages and supports the swinging arm 51a that can swing about the angle a, and the angle roller shaft 27a at the other end, and a sector gear 52 on the opposite side to the groove 51u.
A swing arm 51b swingable about a fulcrum shaft 53b, and a second displacement member driving means for displacing the angle roller 27 in a direction (upward U and downward D) in which the master holding angle θa is changed. Stepping motor 55
And a pinion 56 which is provided integrally with the output shaft of the second stepping motor 55 and always meshes with the sector gear 52 on the swing arm 51b side, and a position detection for detecting a home position which is also an initial position of the angle roller 27. It mainly comprises a sensor 58.

The angle roller 27 has an outer peripheral portion made of silicone rubber, and has a metal angle roller shaft 27a.
And are formed integrally with it. The outer peripheral portion of the angle roller 27 is not limited to the above, and may be metal. The angle roller 27 is rotatably engaged with the angle roller shafts 27a at both ends in the respective grooves 51u of the swing arm pairs 51a and 51b shown in FIGS.
By being supported, it is rotatable in the same direction. When viewed from the axial direction of the platen roller 10, the angle roller 27 is such that the master 8 on the outer peripheral surface contact of the angle roller 27 is always at a position higher than the position of the nip portion N between the thermal head 11 and the platen roller 10 in FIGS. It is arranged so as to be located above. Angle roller 2
Reference numeral 7 denotes a state in which the master 8 having the plate-making master 8 is wound around the outer peripheral surface of the platen roller 10 by the master holding angle θa and occupies a position in a direction away from the thermal head 11. Is rotated by the transport of the sheet. The home position of the angle roller 27 is set, for example, at a substantially central position of the guide groove 29c shown in FIG.

The fulcrum shaft 53a is implanted in the swing arm 51a, and the fulcrum shaft 53b is implanted in the swing arm 51b.
b is supported at the same position in the master conveyance direction X and the vertical direction by the pair of plate making side plates 29a and 29b so as to be rotatable by a predetermined angle. Groove 5 in each swing arm 51a, 51b
The lower end of 1u is bent to allow each swing arm 51a,
An arm connecting portion 51c for connecting the first member 51b substantially integrally, in other words, as a rigid body, is formed. As shown in FIG. 3, the second stepping motor 55 is fixed to the plate making side plate 29b with its output shaft facing the inside of the plate making side plate 29b. The position detection sensor 58 is composed of, for example, a transmission type photo sensor, and is attached to a predetermined position inside the plate making side plate 29b. The position detection sensor 58 is a light shielding piece 51 implanted on the back side of the swing arm 51b in FIG.
d is a predetermined swing position of the swing arm 51b, that is, when the angle roller 27 occupies the home position, the light shielding piece 51d engages and shields light, thereby detecting the home position of the angle roller 27. ing.

In FIG. 2, the symbol θb indicates a master separation angle for transporting the master 8 downstream of the platen roller 10 in the master transport direction X or the master 8 after plate making in a direction away from the thermal head 11. The master separation angle θb is determined by the angle roller shaft 2 of the angle roller 27.
In FIG. 2, the master 8 between the angle roller 27, the platen roller 10, and the thermal head 11 and the heating element are arranged such that the reference numeral 7a is located above the nip portion N between the platen roller 10 and the thermal head 11. The angle roller 2 is set so that the master separation angle θb formed by the extended line of the horizontal plane of the thermal head 11 becomes an acute angle.
7, a platen roller 10 and a thermal head 11 are arranged. Here, the detailed operation of the master angle-of-hold variable means 50 will be described. A predetermined number of drive pulses of the forward drive pulse or the reverse drive pulse is input to the second stepping motor 55 via a motor drive circuit (not shown),
When the stepping motor 55 is driven to rotate by a predetermined number of steps, the rotation driving force is applied to the pinion 56 and the sector gear 52.
Swinging arm 51b and connecting portion 51c
Is transmitted to the swing arm 51a through the shaft and is converted into a swinging motion. Further, while being transmitted to the angle roller shafts 27a at both ends, it is converted into a linear motion in the vertical direction by each guide groove 29c, and finally the angle is changed. The linear displacement motion of the roller 27 in the vertical direction is obtained. Hereinafter, for convenience of description, it is assumed that the angle roller 27 is displaced in the upward direction U in response to the forward rotation drive pulse, and conversely, the angle roller 27 is displaced in the downward direction D in response to the reverse rotation drive pulse. By the above-described operation, for example, when a predetermined number of normal rotation drive pulses are input to the second stepping motor 55, the angle roller 27 occupying the home position moves upward U
, The master holding angle θa increases, the area of the master contact area where the master 8 contacts the outer peripheral surface of the platen roller 10 increases, and the master separation angle θb also increases. Conversely, for example, the second stepping motor 5
By inputting a predetermined number of reverse drive pulses to 5,
When the angle roller 27 is displaced in the downward direction D, the master holding angle θa is reduced, the area of the master contact area where the master 8 contacts the outer peripheral surface of the platen roller 10 is reduced, and the master separation angle θb is also reduced.

On the downstream side in the master transport direction X adjacent to the middle pair of transport rollers 12a and 12b, a fixed blade 13 for cutting the master 8 made into plate or the master 8 not made into plate into a predetermined length.
A rotary blade moving type cutter 13 is provided, which rotates and moves in a master width direction orthogonal to the master transport direction X and has a rotary blade 13a as a movable blade. The cutter 13 is not limited to the rotary blade moving type, but may be a so-called guillotine type in which the movable blade can move up and down.

On the downstream side of the master transport direction X adjacent to the cutter 13, the transport roller middle pair 12a and 12b and the reverse roller pair 1
A master stock means including a suction box 17, an opening / closing plate 16, a suction fan 18, and the like provided below the master transport path between the master conveyance path 4a and 14b. The suction box 17 is fixedly provided between the plate making side plate pair 29a and 29b, and has a space defined so as to form a substantially L shape toward the upstream side of the master transport path. I have.
The suction box 17 is provided with the deflection 8A of the master 8 shown in FIG.
And has a function as a suction storage unit for temporarily storing by sucking.

The opening / closing plate 16 is supported by a pair of plate making side plates 29a and 29b near the suction port formed at the uppermost part of the suction box 17, and is provided with a motor or a solenoid (not shown) for driving the opening / closing plate and the opening / closing plate. A driving force transmitting member such as a sector gear for transmitting the driving force from the driving means to the opening / closing plate 16 is configured to be openable and closable with respect to the suction port. The opening / closing plate 16 is, as shown by a solid line in FIGS. 1 and 7, a guide conveyance position lying directly below the master conveyance path to convey and guide the master 8, and as shown by an imaginary line in FIGS. The master 8 is rotatable and displaceable between the guide transfer position and a deflection suction position where the master 8 is rotated and displaced downward by approximately 90 degrees to store the master 8. When the opening / closing plate 16 occupies the deflection suction position, the suction box 17
Is opened, and above the suction box 17 is formed the above-mentioned suction port for introducing the master 8 having been made.

On the back side of the suction box 17 located on the downstream side of the master transport path, provided between a suction port formed of a slit or a mesh-like small hole and an exhaust port, the plate-formed master 8 is suctioned. A suction fan 18 is provided. The rotation of a suction fan motor (not shown) connected to the suction fan 18 rotates the suction fan 18 to generate an airflow flowing from left to right in FIGS. 1 and 7.
The stencil master 8 is stored in the suction box 17 while being gradually sucked.

The opening / closing plate 16 is driven by the opening / closing plate driving means after the master is cut after the end of the plate making operation.
Rotation from the deflection suction position via the driving force transmission member
By displacing and occupying the guide transport position, the guide of the master 8 is guided so that the distal end of the master 8 is transported to the plate making standby position shown in FIG. 1 and the like without dropping the distal end of the master 8 from the suction port into the suction box 17. It is supposed to. Further, the opening / closing plate 16 occupies the guide conveyance position after the master is cut after the plate making operation is completed, and then the opening / closing plate driving means is driven in the opposite direction to the above, so that the leading end of the master 8 is turned to the reversing roller pair. After being held between the nip portions 14a and 14b and reaching the plate making standby position, the plate is rotated and displaced again to the deflection suction position.

As shown in FIG. 7 above the suction port of the suction box 17
As shown in the figure, a master detection sensor 19 as a deflection detecting means for detecting the deflection 8A of the master 8 formed into a predetermined size having an upwardly convex shape in the plate-making master 8.
Is provided. The master detection sensor 19 includes, for example, a reflection type photo interrupter.

A pair of rotatable upper and lower reversing rollers 14a, 14b for transporting the master 8 is provided downstream of the master transport direction X adjacent to the suction box 17 and the master detection sensor 19.
Are arranged. Each of the reversing roller pairs 14a and 14b has an outer peripheral portion made of silicone rubber, and is formed integrally with a metal shaft. Reverse roller pair 14a, 14b
Are pressed against each other by applying an appropriate pressing force by an urging means such as a spring, and are opposed to each other because both ends of the shafts are rotatably supported by the plate-making side plates 29a and 29b. It is rotatable in the direction. The pair of reversing rollers 14 a and 14 b are provided slightly inclined in a counterclockwise direction, which is a direction in which the master 8 is moved away from the suction port of the suction box 17. The reversing roller 14a is connected to a first stepping motor 35 via a plurality of gears or a rotation transmitting member (not shown) such as a belt, and thereby is driven to rotate clockwise.

The pair of reversing rollers 14a and 14b are connected to each other by the rotation transmitting member including the first stepping motor 35.
It is set so as to rotate at a peripheral speed (transport speed) higher than the peripheral speed (transport speed) of the platen roller 10, and an appropriate front tension is applied to the master 8 while sliding with the master 8. ing. Reversing roller 1
At the shaft end of 4a, a second electromagnetic clutch 34 for connecting and disconnecting the rotational driving force of the first stepping motor 35 to the reversing roller 14a is provided. The second electromagnetic clutch 34 includes, for example, a powder type electromagnetic clutch or a hysteresis type electromagnetic clutch. Note that, instead of the second electromagnetic clutch 34, a single stepping motor independent of the first stepping motor 35 may be driven alone.

Downstream of the pair of reversing rollers 14a, 14b in the master transport direction X, a guide plate 15 for guiding the master 8 or the leading end of the master 8 to a clamper 7 provided on the plate cylinder 1 is provided. It is provided to extend in each axial direction of the pair of reversing rollers 14a, 14b. The plate making device 70 includes a platen roller 10 disposed between the plate making side plate pair 29a and 29b, which is a plate making device main body, and a temperature sensor 30 as temperature detecting means for detecting a temperature in the vicinity of the pair of transport rollers 12a and 12b. However, a humidity sensor 31 is provided as a humidity detecting means for detecting the humidity of the same site. As the temperature sensor 30, a thermistor or the like is preferably used. The temperature sensor 30 and the humidity sensor 31, together with an image amount detecting means 48, a head temperature sensor 32, and the like, which will be described later, detect a characteristic value of a master expansion / contraction-related factor that affects expansion / contraction of a master plate making dimension during plate making. It constitutes a characteristic value detecting means group. In this embodiment, the temperature sensor 30 and the humidity sensor 31 are used in order to grasp temperature and humidity as actual environmental conditions as accurately as possible.
Is arranged inside the main body of the plate making apparatus, but is not limited to this.For example, if it cannot be arranged inside the main body of the plate making apparatus due to layout restrictions of components and the like, in order to detect the temperature and humidity around the outside of the main body of the plate making apparatus. It may be arranged on the outer wall surface of the main body panel outside the main body of the plate making apparatus, or around the installation part of the plate making printing apparatus 80. That is, the temperature detecting means and the humidity detecting means may be provided so as to detect at least one of the temperature and the humidity inside and outside the plate making apparatus main body.

Here, the characteristics and characteristic values of the master expansion / contraction related factors will be supplementarily described. Characteristics of factors related to master expansion / contraction
As characteristic values, at least the following 5
One can be empirically listed. That is, the first of the characteristic values of the master expansion / contraction-related factors is a plate making image amount formed on the master, the second is a temperature inside the plate making device main body,
Third is the humidity inside the plate making apparatus main body, fourth is the temperature of the thermal head 11, and fifth is the type of master corresponding to the strength of the master.

As the image amount detecting means 48 for detecting the amount of plate making image formed on the master 8, Japanese Patent Application Laid-Open No. 9-19352
The same means as that described in paragraph (0033) of JP-A-6 is used. That is, master 8 for one version
With respect to the number of heating elements required for heating and punching the entire plate, the number of heating elements used for heating and punching and making the master 8 from the image information actually read by the scanner 47 of the original reading device. By determining the ratio of the numbers, that is, the drilling rate (opening rate) of the master 8,
(In other words, approximately the same as the print image amount printed on the printing paper). The image amount detecting means 48 is a CCD provided in the scanner 47.
Receiving an analog image electric signal read and converted by an image sensor composed of a (charge coupled device) or the like, and receiving a digital image electric signal converted by the A / D converter via an image signal processing device; An image memory temporarily stored as image data, and an image memory formed on the master 8 while sequentially calling image data once stored in the image memory.
The image signal processing device has a function of activating a plate making control device for controlling the drive of the thermal head 11 by detecting and recognizing the image amount of the plate making image for the plate.

FIG. 9 shows a specific example of a head temperature sensor 32 as a thermal head temperature detecting means for detecting the temperature of the thermal head 11. As the head temperature sensor 32, a thermistor is preferably used. The temperature of the thermal head 11 is detected on the thin film substrate 11c on which the heating elements of the thermal head 11 are arranged as shown in FIG.
It is desirable that the surface is close to the surface of the center of the heating element surrounded by the common electrode and the lead electrode, for example. The thermal head substrate 11 on the circuit board mounted on the thermal head 11
The temperature of the thermal head body is detected on a. The location of the head temperature sensor 32 is not limited to the thermal head substrate 11a, but may be provided inside the heat sink 11b.

On the left side of FIG. 1 of the plate making apparatus 70, a porous cylindrical support cylinder and a mesh screen made of a resin or metal mesh wound around a plurality of layers so as to cover the outer periphery of the support cylinder are provided. (Not shown)) is provided. The plate cylinder 1 has an opening 1a (printable area) having a large number of ink-permeable openings,
It has a well-known configuration including a non-opening (non-printable area) provided with a clamper 7 and the like. The plate cylinder 1 is wound around and fixed to an outer peripheral portion of an end plate flange (not shown), and is rotatably supported around a support shaft also serving as an ink pipe 5 described later. The plate cylinder 1 is rotated in a direction indicated by an arrow (clockwise) in the figure by transmitting the rotational driving force of the electric motor by a drive transmitting means such as a gear or a belt connected to an electric motor (not shown).

Inside the plate cylinder 1, a side plate (not shown) is rotatably supported by a side plate, and the rotational driving force of the electric motor is transmitted by drive transmission means such as a gear (not shown) to synchronize with the plate cylinder 1. An ink roller 2 that is driven to rotate in the direction of an arrow (clockwise) in the figure and supplies ink by contacting the inner peripheral surface of the plate cylinder 1 is arranged in parallel with a small gap from the ink roller 2. A doctor roller 3 that forms a wedge-shaped ink pool 4 between the roller 2 and an ink pipe 5 that supplies ink to the ink pool 4 is disposed. Note that the ink roller 2, the doctor roller 3, and the ink pipe 5 constitute ink supply means. The ink in the ink reservoir 4 is sucked from an ink pack (not shown) provided outside the plate cylinder 1 and supplied from a supply hole of an ink pipe 5.

On a part of the outer peripheral surface of the non-opening portion of the plate cylinder 1, a ferromagnetic stage 6 provided along one generatrix of the plate cylinder 1, and provided on both side ends of the stage 6. And a clamper 7 having a rubber magnet that is rotatably mounted on the clamper shaft and that can be opened and closed with respect to the plane portion of the stage 6. The clamper 7 is opened and closed at a predetermined position by an opening and closing device (not shown). Plate cylinder 1
Is stopped in a state where the clamper 7 is located substantially on the right side indicated by a virtual line in FIG. 1, that is, at the plate feeding position. The plate cylinder 1 is configured as a plate cylinder unit integrally formed with the ink pack and the like, and is removably inserted into and removed from the main body frame of the plate making and printing apparatus 80 in the axial direction of the ink pipe 5.

In the vicinity of the lower side of the outer peripheral surface of the plate cylinder 1 facing the ink roller 2, the cam and the like (not shown) can freely contact and separate from the outer peripheral surface of the plate cylinder 1 in synchronization with the feeding of the printing paper (not shown). A press roller 21 is provided as a pressing means which is urged by a spring member (not shown) in a direction of pressing against the outer peripheral surface of the plate cylinder 1. The press roller 21 includes a pair of press roller arms 22, 22 fixed to both ends of an arm shaft 22 a rotatably supported by a housing side plate (not shown).
A well-known configuration in which the shaft portion is rotatably supported and held at a position separated from the outer peripheral surface of the plate cylinder 1 by a locking means (not shown) except when paper is passed.

At the lower right side of the plate cylinder 1 in FIG. 1, a paper feed tray (not shown) on which print papers (not shown) are loaded and lifted up and down, and a separate paper feeder for separating and feeding the print papers one by one A paper feeder is provided which includes a member and a pair of registration rollers 20, 20 and the like which transport the separated and fed printing paper between the outer peripheral surface of the plate cylinder 1 and the press roller 21 at a time. ing. On the left side of the plate cylinder 1 in FIG. 1, a plate discharging device (not shown) for separating the used master 8 from the plate cylinder 1 and discharging the same is arranged. Below the plate discharging device, a peeling claw 24 whose tip is freely supported on the outer circumferential surface of the plate cylinder 1 for peeling the printing paper from the outer circumferential surface of the plate cylinder 1, and the peeling claw 24 peels and discharges the paper. A paper discharge device is provided which includes a paper discharge tray (not shown) for loading printed paper. Further, above the plate cylinder 1 and the plate making device 70, a document reading device (not shown) provided with a scanner 47 and the like shown in FIG.

The detailed configuration of the operation panel 40 will be described with reference to FIG. The operation panel 40 is provided above the document reading device. The operation panel 40 includes a start key 41 as an operation start unit for starting a series of processes (operations) from reading of an image of a document to plate discharging, plate making, plate feeding, plate printing, and sheet discharging. , A numeric keypad 43 for setting and inputting the number of prints, a print key 42 for starting the printing operation for the number of prints set (input / input) by the numeric keypad 43, and displaying the operation status and messages. (LCD (Liquid Crystal Display)) display section 45 and the like. The LCD display unit 45 is driven via a liquid crystal drive circuit or the like.

Next, a control configuration of the plate-making printing apparatus 80 will be described with reference to FIG. In FIG. 5, reference numeral 65 denotes a control device for mainly controlling the plate making device 70 of the plate making printing device 80. The control device 65 includes a C
PU (central processing unit), I / O (input / output) port,
A microcomputer having a ROM (read only storage device), a RAM (read / write storage device), a timer, and the like, and having them connected by a signal bus is provided.

The CPU of the control device 65 (hereinafter sometimes simply referred to as “control device 65” for simplicity of description) constitutes the above-described characteristic value detecting means group via the input port. , The image amount detection means 48, the temperature sensor 30, the humidity sensor 31, and the head temperature sensor 32, respectively, and receive data signals from these means and each sensor. The control device 65
Is connected to the master detection sensor 19 through the input port.
And the position detection sensor 58 and the various keys (the start key 41, the print key 42, and the numeric keypad 43) of the operation panel 40 are electrically connected to each other. Receive a data signal. The control device 65 is connected via the output port
LCD display section 45 of operation panel 40 and electromagnetic brake 3
7, the first stepping motor 35, the second stepping motor 55, the first electromagnetic clutch 33, and the second electromagnetic clutch 34, which are electrically connected to each other via various drive circuits (not shown). Various command signals are transmitted to the LCD display unit 45, the electromagnetic brake 37, the first stepping motor 35, the second stepping motor 55, the first electromagnetic clutch 33, and the second electromagnetic clutch 34, respectively.
The control device 65 is electrically connected to the open / close plate driving means of the master stock means and the suction fan driving motor via the output port, respectively.
Various command signals are transmitted to the opening / closing plate driving means and the suction fan driving motor via various driving circuits (not shown).

In this embodiment, the control device 65 has the following various control functions. First, the control device 65 controls the master holding angle based on signals from the image amount detecting means 48, the temperature sensor 30, the humidity sensor 31 (a group of characteristic value detecting means), the head temperature sensor 32, and the position detecting sensor 58. θ
In order to change a, that is, to change the position of the angle roller 27 in the vertical direction, it has a function as a control means for controlling the second stepping motor 55 of the master angle changing means 50.

Secondly, the control device 65 serves as plate making operation control means for inhibiting a plate making operation based on a signal from a master type detecting means described later, when the master is different from a master set to be used in advance. It has the function of At this time, the control device 65 has a function of controlling the LCD display unit 45 to display, for example, "The master is different from the set master, replace the master with a proper one." .

Third, the center Nc of the nip between the platen roller 10 and the thermal head 11 and the transport roller
In order not to always loosen the master 8 while paying attention to the change in the length of the master 8 between the nip portions of the a and 12b, the control device 65 controls the angle roller 27 in the vertical direction. The first stepping motor 35 and the first electromagnetic clutch 33 are provided to compensate for the amount of change in the length of the master 8 between the nip center Nc and the nip of the pair of transport rollers 12a and 12b in accordance with the amount of positional displacement. , The second electromagnetic clutch 34
And a function of controlling the electromagnetic brake 37.

The ROM in the control device 65 stores a data table obtained by an experiment or the like in advance for performing control by the control device 65 having the above-described first to third functions, a program shown in FIG. A program for performing the operation is performed is stored in advance. The RAM in the control device 65 performs input / output of these signals by temporarily storing the determination results and calculation results of the CPU and storing output signals from each sensor and the like as needed. The data table includes, for example, relation data between each characteristic value detected by the four characteristic value detecting means and the master holding angle θa, and the vertical position of the angle roller 27 corresponding to the master holding angle θa. And the number of forward or reverse rotation drive pulses to the second stepping motor 55.

The master type detecting means is based on the above-mentioned master detecting sensor 19, the above-mentioned master stock means provided with the above-mentioned suction box 17, and the on / off signal from the master detecting sensor 19. The timer includes a timer of the control device 65 as a deflection suction timing means for measuring a time when the deflection 8A of the master 8 is sucked.

Next, the operation will be described with reference to FIGS. First, a document (not shown) is set on a document table provided in a document reading device (not shown).
In step S1, when the start key 41 of the operation panel 40 is pressed, a plate making start signal is generated, and the signal is input to the control device 65 to start plate making. First, the scanner 47 pre-scans the surface of the set original to read the original image, and at the same time, detects the amount of plate making image corresponding to the original by the image amount detecting means 48, and transmits the signal to the control device 65. You. Then, based on a command from the control device 65, the image amount detecting means 4
8 is checked based on the data signal from the master 8, and the ratio of punching to the master 8 for one version is checked.
0 and a data signal relating to temperature and humidity from the humidity sensor 31, a data signal relating to the vertical position of the angle roller 27 from the position detection sensor 58, or the thermal head 1 from the head temperature sensor 32 during the start of plate making.
The position of the angle roller 27 in the vertical direction is set by controlling the second stepping motor 55 based on the data signal relating to the first temperature as described later. At the same time, the first stepping motor 35 and the first electromagnetic clutch 33 are controlled by a command from the control device 65 as described later.
And by controlling the second electromagnetic clutch 34,
According to the amount of displacement of the angle roller 27 in the vertical direction,
A control operation is performed to keep the master 8 between the nip center Nc and the nip between the pair of transport rollers 12a and 12b from being slackened.

When the electric motor is driven, the plate cylinder 1 is rotated, and a used master (not shown) wound around the plate cylinder 1 is peeled and discarded by a plate discharging device (not shown). Next, the plate cylinder 1 is stopped at the plate feeding position, and the clamper 7 is opened by an opening / closing device (not shown) to enter a plate feeding standby state. The plate making process is started in parallel with the rotation of the plate cylinder 1 in the plate discharging process.

That is, when the first stepping motor 35 is driven, the platen roller 10 and the pair of conveying rollers 12a and 12b start rotating, and the master 8 is conveyed while being pulled out from the master roll 8a. A force is applied to the tip of the master 8 in the direction in which it is lifted upward by the pair of reversing rollers 14a, 14b inclined as described above.
Occupies the guide transport position and the leading end of the master 8 is stopped by being sandwiched between the pair of reversing rollers 14a and 14b, so that the leading end of the master 8 moves upward as shown in FIG. The deflection 8A is formed by being raised in a convex shape. When the deflection 8A reaches a predetermined size, it is turned on and detected by the master detection sensor 19 (see step S2).

After a lapse of a set delay time from the ON / detection of the master detection sensor 19, the opening / closing plate driving means is driven to rotate the opening / closing plate 16 from the state occupying the guide conveyance position to the deflection suction position. The suction port is displaced to form a suction port above the suction box 17, and the suction fan 18 is rotated by driving the suction fan drive motor, whereby the left side of the suction box 17 in FIGS. As a result, an airflow from the right side to the right side is generated, so that the deflection 8A formed at the tip of the master 8 is stored while being drawn in (step S3).
reference). When the deflection 8A at the tip of the master 8 is sucked and the deflection 8A becomes small and is not detected by the master detection sensor 19, the master detection sensor 19
Is turned off, and the control device 65 determines whether the detection is turned off within a predetermined set time (step S).
4, see step S5).

In the case of the stiff master 8 as the type of the master, the deflecting suction time until the deflecting 8A of a predetermined size is sucked and drawn in by the suction box 17 is prolonged, whereby the master detecting sensor 19 is turned off. It takes longer to do it. On the other hand, in the case of the master 8 having a weak waist, the suction box 17
Since A is immediately sucked and drawn, the time until the master detection sensor 19 is turned off is shortened. As described above, the timer of the control device 65 measures the deflection suction time when the deflection 8A of a predetermined size is sucked by the suction box 17 based on the on / off signal from the master detection sensor 19. Thus, the type of master corresponding to the strength of the waist of the master 8 can be detected as a substitute for the strength of the waist of the master 8.

At this time, based on the signal from the timer, the control device 65 determines, if different from the master set to be used in advance, that is, the deflection suction time from the timer is not within the predetermined set time. In such a case, the plate making operation is prohibited and stopped, and the LCD display unit 45 is controlled to display, for example, a message indicating that "the master is different from the set master, replace the master with a regular one." Let. In this case, the operator operates the LCD display 45
The operation for replacing the master roll 8a with the regular master roll 8a is performed according to the message displayed in step S7 and step S8 in the display stop mode. Conversely, in step S5, when the control device 65 determines that the master is set to be used in advance, that is, from the data signal related to the deflection suction time measured by the timer, the control device 65 sets the master within a predetermined set time. , The plate making operation is continued. (Step S6
reference).

In steps S7 and S8, the present invention is not limited to the above-described display stop mode. For example, it may be possible to freely select a disregard mode in which this operation is ignored and the operation proceeds to the same operation as in step S6. . In the ignore mode, for example, the operation panel 40 may be provided with a switching key for switching the operation mode from the display stop mode to the ignore mode.

In step S1 of FIG. 11, the back tension F1 after the start of the plate making operation is set in advance to be larger than the front tension F2 as described above. This is a problem as described in the related art, that is, when the plate-making master 8 is conveyed by the platen roller 10, a non-perforated portion where there is no increase in frictional force (conveyance resistance) and conveyance delay is less likely to occur. This is to prevent the slack due to uneven feeding of the master 8 from occurring in the perforated portion where the conveyance delay occurs due to the increase in the frictional force (conveyance resistance).

In addition to this, the control device 65 receives a data signal from the temperature sensor 30 relating to the detection of the temperature of the main body 70 of the plate making apparatus, and a data signal from the image amount detecting means 48 relating to the amount of plate making image formed on the master 8. The following control is performed on the basis of the data signal relating to the humidity detection of the main body of the plate making device 70 from the humidity sensor 31. That is, the control device 65
When the transfer resistance of the master 8 is large due to the large number of perforated image portions, or when the humidity is high and the moisture or the like adheres to the surface of the master 8, the master 8 is easily attached to the contact surface with the thermal head 11. In a high-humidity environment in which the frictional force increases, the angle roller 27 is displaced in the upward direction U in FIGS. 1 and 2 by applying a predetermined number of forward drive pulses to the second stepping motor 55. The holding angle θa is increased and the platen roller 1
The contact area between the outer peripheral surface 0 and the master 8 is increased. Such an increase in the contact area between the outer peripheral surface of the platen roller 10 and the master 8 increases the frictional resistance on the contact surface as a whole, so that the slip amount between the master 8 and the platen roller 10 decreases. The plate making length is adjusted to an appropriate range.

In particular, when the environmental temperature is high in addition to the above-mentioned environment, the heat stored in the thermal head 11 is increased, and the master 8 is softened and easily extended, so that the diameter of the hole formed in the master 8 is increased. Therefore, the conveyance resistance of the master 8 is further increased, so that the angle roller 27 is further displaced in the upward direction U in FIGS. By further increasing the holding angle θa, the contact area between the outer peripheral surface of the platen roller 10 and the master 8 is further increased. Since the contact area between the outer peripheral surface of the platen roller 10 and the master 8 further increases, the frictional resistance on the contact surface as a whole further increases.
The amount of slip between the master 8 and the platen roller 10 is reduced, and the plate making length is adjusted to an appropriate range.

Conversely, in a low-temperature and low-humidity environment in which the temperature and humidity are low and the frictional force between the master 8 and the thermal head 11 is low, the control device 65 sends the second stepping motor 55 a predetermined , The angle roller 27 is displaced in the downward direction U to reduce the master holding angle θa, and the contact area between the outer peripheral surface of the platen roller 10 and the master 8 is reduced. Reduce. By reducing the contact area between the outer peripheral surface of the platen roller 10 and the master 8 as described above, the frictional resistance on the contact surface as a whole becomes smaller than that in the above-described operation example. The amount is increased and the plate making length is adjusted to an appropriate range.

During the plate making operation, the controller 65
Further, taking into account the temperature of the thermal head 11 detected by the head temperature sensor 32, the position of the angle roller 27 in the up-down direction is changed so that the master holding angle θa
To adjust. That is, as shown in FIG. 10, since the temperature rise of the thermal head 11 is negligible at the beginning of the plate making operation (at the beginning of the plate length), it is necessary to change the master holding angle θa accordingly. However, since the temperature rises due to heat storage of the thermal head 11 or the like during the plate making operation, the master holding angle θa needs to be changed accordingly.

As described above, when the angle roller 27 is displaced in the upward direction U to increase the master holding angle θa, the nip between the nip portion center Nc of the platen roller 10 and the thermal head 11 and the nip between the pair of transport rollers 12a and 12b. In order not to extend the length of the master 8 by applying excessive tension to the master 8 between the nip portion and the nip portion between the nip portion center Nc and the nip portion of the pair of transport rollers 12a and 12b. 8, the length of the master 8 between the nip center Nc and the nip of the pair of transport rollers 12a and 12b is changed according to the amount of displacement of the angle roller 27 in the upward direction U. It needs to be longer. Therefore, the first electromagnetic clutch 33 and the second electromagnetic clutch 34
Are turned on, the downstream portion of the master 8 is securely locked so as not to move to the nip portions of the pair of conveying rollers 12a and 12b and the nip portions of the reversing rollers 14a and 14b. With the predetermined back tension F1 caused by the brake 37 being lower than the front tension F2, the length of the master 8 between the nip portion center Nc and the nip portion of the pair of transport rollers 12a and 12b is increased by the necessary length. , First stepping motor 35
, The platen roller 10 is rotated by a predetermined angle so that the pair of conveying rollers 12a, 1
The master 8 may be sent between the nip portion 2b and the nip portion.

On the contrary, the angle roller 27
Is displaced in the downward direction D to reduce the master holding angle θa, the nip center Nc and the conveyance roller middle pair 12a,
In order to prevent the master 8 from being loosened between the nip portion 12b and the nip portion 12b, the nip portion center Nc and the transport roller middle pair 12a,
It is necessary to shorten the length of the master 8 between the nip portion 12b and the nip portion. Therefore, the first electromagnetic clutch 33 and the second
When the electromagnetic clutch 34 is turned on, the electromagnetic brake 3
7, a predetermined back tension F1 is applied, and the center Nc of the nip portion and the transport roller middle pair 12a, 12
By supplying a predetermined drive pulse to the first stepping motor 35 by a necessary amount to shorten the length of the master 8 between the nip portion of the platen roller b, the platen roller 10, the pair of conveying rollers 12a and 12b, and the pair of reversing rollers. 14a, 14b
May be sent to the downstream end of the master 8 in the master transport direction X by rotating all of them.

In the present embodiment, the length of the master 8 is adjusted when the angle roller 27 is displaced. However, the present invention is not limited to this. Set the peripheral speed to platen roller 10
The length may be adjusted by setting faster than that of.

FIGS. 8A and 8B show the differences between the conventional method for adjusting the plate making length and the method according to the present invention. For example, in the conventional system disclosed in Japanese Patent Application Laid-Open No. Hei 7-156520, for example, as shown in FIG.
2b is provided with a torque limiter,
A method of controlling the tension (front tension) generated in the master 8 having been made by setting the peripheral speeds of 2a and 12b faster than that of the platen roller 10 and adjusting the transmission torque of the torque limiter has been adopted. . However, in this method, one end of the master is pulled to the downstream side in the master transport direction X to apply front tension to the master 8 which has been made and adjust the length of the master, so that the thickness of the porous support is reduced. In the case of a master 8 in which the strength at the perforated portion is greatly reduced, such as a thin master 8 or a master having no porous support at all, when the front tension is applied, unevenness in tension or a perforated portion having reduced strength is obtained. Easily expands, so that a large front tension cannot be applied. This makes it easy for the master 8 which has already been made to shrink and deform, and the length of the plate making, that is, the reproducibility of the plate making image dimension. Was difficult to satisfy.

However, in this embodiment, as shown in FIG. 8 (b), the master holding angle θa is varied and controlled based on each signal from each of the characteristic value detecting means groups, so that the platen roller 10 outer peripheral surface and master 8 with prepress
Adjustment of the contact area with the platen roller 10
The frictional resistance at the contact surface between the outer peripheral surface of the master and the master 8 which has been made is adjusted to increase or decrease the predetermined front tension F2 from the platen roller 10 in the master transport direction X without causing a problem as in the prior art. It is given to the master 8 on the downstream side, which has been made.

This will be described in more detail as follows. In FIG. 8B, when the transport operation of the prepressed master 8 is considered in a state of static force balance, the transfer is applied to the prepressed master 8 downstream in the master transport direction X via the angle roller 27. The front tension F2 is
It is considered that a front tension F2 of a predetermined size is applied at the master contact boundary Mb. The front tension F acting on the stencil master 8 as it goes upstream in the master transport direction X from the master contact boundary Mb.
2 can be seen as gradually decreasing as if attenuated due to the frictional resistance between the outer peripheral surface of the platen roller 10 and the master 8, so that the master 8 is actually heated by the heating element of the thermal head 11. It is conceivable that the front hole F2 having a moderately reduced size, that is, a moderate front tension F2 that does not cause the above-described problem, acts in the portion where the hole is melted and perforated. In addition to the above operation, the outer peripheral surface of the platen roller 10 is heated and perforated from the nip center Nc toward the master contact boundary Mb immediately after the master 8 is actually heated and perforated by the heating element of the thermal head 11. Since the master 8 immediately after moving while substantially holding the portion by the frictional resistance, it is considered that the cooling action is effectively performed while suppressing the heat shrinkage of the portion.

As described with reference to FIG.
Since the temperature rise of the thermal head 11 during plate making cannot be ignored, it is necessary to consider the effect of the heat storage of the platen roller 10. θa
To adjust.

With the continuous rotation of the suction fan 18, master making is performed while the master 8 is successively drawn into the suction box 17 and stored in the suction box 17. On the other hand, at the same time as the rotation of the platen roller 10 starts, the document is conveyed to the document reading unit. The optical information of the document read by the scanner 47 of the document reading unit is photoelectrically converted by an image sensor into an analog image signal.
A thermal head 1 based on a digital image signal processed and transmitted via a converter and a plate-making control device;
One of the heating elements is selectively energized by a pulse to generate heat, and the master 8 is selectively heated and melted in accordance with image information to form a hole.
Plate making is performed.

On the other hand, the plate cylinder 1 rotates and stops until the clamper 7 reaches the plate feeding position which is substantially rightward in FIG. When the plate cylinder 1 stops at the plate feeding position, the clamper 7 is opened by the opening / closing device, and the plate feeding is in a standby state. At the same time when the clamper 7 is released, the second electromagnetic clutch 34 is energized under a command from the control device 65, so that the rotational driving force of the first stepping motor 35 is applied to the reversing roller 14a via the rotation transmitting member. Then, the pair of reversing rollers 14a and 14b is rotated by a predetermined angle, and the leading end of the master 8 having been made is guided by the guide plate 15 and inserted between the stage 6 and the clamper 7. Reversing roller pair 14a,
14b is rotated by a predetermined angle, and the number of steps of the first stepping motor 35 reaches a certain set value correspondingly,
The leading end of the master 8 having been made is the stage 6 and the clamper 7
Is determined, the clamper 7 is closed by the opening / closing device, and the leading end of the stencil master 8 is sucked and clamped between the stage 6 and the clamper 7.

After the leading end of the master 8 has been clamped, the plate cylinder 1 resumes rotation by driving the electric motor, and the master 8 is pulled out of the suction box 17 while the reversing roller pair 14a, 14b is being pulled out. The plate is fed to the outer peripheral surface of the plate cylinder 1 and is wound around the outer peripheral surface of the plate cylinder 1 without generating winding wrinkles. When it is determined that the master drive to the master 8 and the conveyance of the master 8 having the set amount of the master made by the rotation drive of the first stepping motor 35 by the predetermined number of steps are completed, the rotation drive of the first stepping motor 35 is stopped. The platen roller 10 and the transport roller middle pair 12a, 12b
In addition, the rotation of the pair of reversing rollers 14a and 14b is stopped, and the cutter 13 is operated to cut the stencil master 8 having been made. At this time, before the master 8 is completely pulled out of the suction box 17 by the rotation of the plate cylinder 1, the cutter 13
Of the master 8 is terminated, so that the rear end of the master 8 is not torn off. At this time, when the second electromagnetic clutch 34 is turned off, the pair of reversing rollers 14a and 14b is rotated and driven by the rotation of the plate cylinder 1 via the master 8, so that the master 8 The generation of wrinkles can be more reliably prevented by the application of a large tension. The rear end of the cut master 8 having been cut is the plate cylinder 1
Is pulled out of the plate making device 70 by the rotation of
At the stage when the master 8 is completely wound on the outer peripheral surface of the master cylinder, winding of the master 8 having been made on the plate cylinder 1 is completed, and the suction box 1
The remaining of the master 8 and the like are determined by a sensor or the like provided near the suction port 7 described above.

When the winding of the master 8 having been made on the plate cylinder 1 is completed, the printing process is started. That is, one sheet of printing paper stacked on the sheet feeding tray is separated and fed by the separation sheet feeding member of the sheet feeding device, and the timing is adjusted by the registration roller pairs 20 and 20 so that the printing drum 1 It is transported between the outer peripheral surface and the press roller 21. When the passage of the printing paper is detected by a paper detection sensor (not shown) disposed near the downstream of the registration roller pair 20, 20 in the master transport direction X, the locking means is released, and the press roller 21 is released. Is continuously pressed by the prepressed master 8 (not shown in FIG. 1), which is wound around the outer peripheral surface of the plate cylinder 1, by the urging force of the spring member. What is called plate printing is performed for bringing the master 8 into close contact with the outer peripheral surface of the plate cylinder 1. In this printing, the ink oozes from the perforated portion of the plate cylinder 1 to the perforated portion of the stencil master 8 and is transferred to the surface of the printing paper, thereby performing stencil printing.
At this time, the ink roller 2 also rotates in the same direction as the rotation direction of the plate cylinder 1. The ink in the ink reservoir 4 is attached to the surface of the ink roller 2 by the rotation of the ink roller 2, and the amount thereof is regulated when passing through the gap between the ink roller 2 and the doctor roller 3. Supplied to

The leading end of the stencil-printed printing paper is separated from the printing drum 1 by the peeling claw 24 approaching the outer peripheral surface of the printing drum 1.
The printing paper that has been peeled off from the master 8 that has already undergone plate making and that has been peeled off is discharged and stacked on the discharge tray. After the printing, the press roller 21 is separated from the plate cylinder 1 and
Returns to the initial position where the clamper 7 is located almost directly above in FIG. 1, and enters a printing standby state. In parallel with the plate printing process, the opening / closing plate 16 is rotated and displaced 90 degrees clockwise to occupy the guide transport position, and the rotation of the suction fan 18 is stopped.

Thereafter, the platen roller 10, the tension roller upper / lower pair 9b, 9a, and the transport roller middle pair 12a, 12
b and the pair of reversing rollers 14a and 14b resume rotation, and the cut end of the master 8 is moved to the pair of reversing rollers 14a and 14a.
It is sent toward the nip portion 14b. If it is determined from the number of pulses of the first stepping motor 35 that the cut end of the master 8 has reached the nip portion of the reversing roller pair 14a, 14b and has been nipped, the platen roller 10, the tension roller upper / lower pair 9b, 9a, Roller middle pair 12a,
The rotation of the pair 12b and the pair of reversing rollers 14a, 14b is stopped, and at the same time, the opening / closing plate 16 also rotates counterclockwise to return to the initial position of the deflection suction position, and a plate making standby state for the next plate making. become.

After the printing with the printing, the operator visually checks the printed matter discharged to the paper discharge tray and appropriately determines whether or not to perform the normal printing operation. When the number of sheets is set and the print key 42 is pressed, the same operations of feeding, normal printing, and discharging as described above are sequentially performed.

According to the present embodiment, the following advantages can be obtained in addition to the effects described below, by having the above-described configuration. According to the present embodiment, first, the back tension applying means is disposed between the master storage means and the platen roller, and is capable of rotating in contact with the master on the upstream side in the master transport direction. By providing the braking means for braking the rotation of the tension roller, the back tension can be reliably applied to the master upstream of the platen roller in the master transport direction with a simple configuration. Secondly, according to the present embodiment, the braking means can change the magnitude of the back tension by changing the braking force according to the type of the master. Regardless, the first advantage is obtained. According to the present embodiment, the third
In addition, based on a signal from the master type detection means, by having a plate making operation control means for inhibiting the plate making operation when different from the master set to be used in advance,
In addition to the above first and second advantages, it is possible to prevent problems such as wrinkles of the master that may be caused by performing a plate making operation using a master different from a master set to be used in advance. be able to. Fourth, according to the present embodiment, the master type detecting means includes a deflection detecting means for detecting deflection of the master formed in a predetermined size, and a suction storage for sucking and temporarily storing the deflection of the master. Means, based on a signal from the deflection detection means,
Utilizing the fact that the stiffness of the master (the strength of the master) differs depending on the type of the master, for example, by including the sway time measuring means for measuring the time when the stiffness of the master is sucked by the suction storage means Therefore, the type of the master can be detected with a simple configuration in the configuration of a normal plate making apparatus having a suction storage unit.

When it is desired to reduce the rotational rubbing resistance or the like in each groove 51u of the angle roller shaft 27a, a rolling bearing is attached to the end of each angle roller shaft 27a, and then each of the swing arm pairs 51a and 51b is mounted. It may be rotatably and movably supported in the groove 51u. The master holding angle changing means 50 has a simple configuration,
If you don't need that advantage, you are not limited to this,
The same swing arm 51b and the same two second stepping motors 55 for swinging and driving the same swing arm 51b are arranged on each of the plate making side plates 29a and 29b, and the angle rollers 27 are arranged at the same position and the same phase at both ends. For example, it may be displaced in the upward direction U or the downward direction D in parallel with the axial direction of the platen roller shaft 10a.

The master angle-of-hold variable means includes a master angle-of-hold θ
If there is no need to change a so widely,
The angle roller 27 may be displaced and driven along the master transport direction X (horizontal direction), without being limited to the master holding angle varying means 50 shown in FIG. In this configuration, the vertical positional relationship between the nip center Nc and the angle roller shaft 27a, the size of the outer diameter of the angle roller 27, and the like are appropriately set. May be arranged in a state rotated 90 degrees counterclockwise. In this configuration example, the angle roller 27 is displaced along the master transport direction X (horizontal direction). Control to compensate for the change in length of the master 8
There is an advantage that the configuration can be made unnecessary.

The master angle-of-hold variable means is not limited to the above-described ones.
Nos. 6, 6 shown in FIGS.
A person skilled in the art can also realize that a, 7, and 8 are configured to be displaceable or extendable.

The embodiment of the present invention is not limited to the above embodiment and the like, but the master holding angle with a fine grain of wood performed by the control device 65 based on each signal from the characteristic value detecting means group as in the above embodiment and the like. If the above-mentioned advantages and effects to be described later obtained by the variable control of θa are not so desired, the image amount detecting means 48 as the characteristic value detecting means, the temperature sensor 30, the humidity sensor 31, and the head temperature sensor 32 may be used. Any one of them may be provided, and the control means may perform variable control of the master holding angle θa based on a signal from any one of the characteristic value detecting means. See Items 7, 8, 9, and 10). Further, the image amount detecting means 48 as the characteristic value detecting means, the temperature sensor 3
0, the humidity sensor 31, and the head temperature sensor 32, if it is desired to perform variable control of the master holding angle θa with a finer grain than that provided by arranging any one of the head sensor 32, at least two control means are required. The variable control of the master holding angle θa may be performed based on each signal from the characteristic value detecting means described above (see claim 11).

The embodiment of the present invention is not limited to the above-described embodiment and the above-described control structure. If it is desired to perform variable control of the master holding angle θa with a finer grain, the master expansion / contraction-related characteristic is regarded as the master expansion / contraction-related factor. And the control type may be a master type detecting means for detecting the type of the master as the characteristic value detecting means. That is, the control device 65 controls the image amount detecting means 4 as the characteristic value detecting means.
8. In addition to the signals from the temperature sensor 30, the humidity sensor 31, and the head temperature sensor 32, the master holding angle θa is changed based on the master type detection signal from the timer as the master type detection means. A function of controlling the second stepping motor 55 of the master embedment angle varying means 50 is added. Also in this case, only one of the timers is individually provided, or variable control of the master holding angle θa is performed based on signals from at least two or more characteristic value detecting means including the timer. May be configured to be performed.

The embodiment of the present invention is not limited to the above-described embodiment and the above-described control configuration, but may be as follows. In other words, the control structure may be such that there is a control means for controlling the electromagnetic brake 37 as the braking means so as to change the braking force based on the signal of the master type from the timer of the master type detecting means. In this configuration, for example, the tension roller upper and lower pairs 9b and 9a are configured to be detachable from the plate making side plate pairs 29a and 29b, and the braking roller according to the type of the master is mechanically preliminarily applied with the tension roller upper and lower pairs 9b and 9b. A configuration example in which a plurality of 9a are prepared and made detachable is also included.

The master 8 is not limited to the one described above, and may be a master in which the thickness of the porous support of the master 8 is reduced. For example, Japanese Patent Application Laid-Open No. 11-7794 proposed by the present applicant.
The synthetic fiber base master 2 described in Japanese Patent Publication No. 9 may be used, or a master in which a molten resin is applied to a synthetic resin film to form a resin film integrally with the synthetic resin film may be used. Can be. As described above, if it becomes possible to perform the variable control of the back tension F1 and the variable control of the master holding angle θa according to the type of the master, not only the conventional problems can be solved but also the effects described later can be obtained. Needless to say, it is possible to improve the print quality, reduce the cost of the master (plate) itself, and reduce the printing cost according to the type of master used.

As described above, the present invention has been described with reference to the specific embodiments and the examples included therein. However, the configuration of the present invention is not limited to the above-described ones, It is obvious to those skilled in the art that various embodiments and examples may be configured in combination or alone, and various embodiments and examples may be configured according to the necessity, purpose, application, and the like within the scope of the present invention. .

[0096]

As described above, according to the present invention,
A new plate-making apparatus and plate-making printing apparatus can be provided by solving the problems of the conventional apparatus as described above. The effects of each claim are as follows. According to the first aspect of the present invention, by having the master holding angle changing means for changing the master holding angle, for example, in a case where the front tension is applied to the master immediately after the plate making by heating with the thermal head, the master holding angle is used. The master contacting the outer peripheral surface of the platen roller within the range described above has a synergistic effect of the cooling effect by the rotation of the platen roller together with the action of suppressing the heat shrinkage by the frictional resistance according to the contact area. It is possible to suppress expansion and contraction of the master at the time of plate making while applying front tension, and by changing the angle of holding the master where such an action is performed, it is possible to use not only the conventional master but also the porous support Even when using a master with a thin body or a master without any porous support, it can prevent wrinkles from occurring. It is possible to improve the image size reproducibility in turn during plate making.

According to the second aspect of the present invention, the master hugging angle changing means is arranged downstream of the platen roller in the master conveyance direction, and changes the master hugging angle by contacting the master downstream of the master conveyance direction. A displacement member capable of displacing in the direction, and a displacement member driving means for displacing the displacement member in a direction in which the master holding angle is changed.
In addition to the effects of the described invention, the master angle-of-hold variable means can be realized with a simple configuration.

According to the third aspect of the present invention, since the displacement member is a rotatable roller, the displacement member can be realized with a simple configuration in addition to the effect of the second aspect of the invention.

According to the fourth aspect of the present invention, a transport roller is provided downstream of the displacement member in the master transport direction and moves the master downstream in the master transport direction, and a transport roller drive for driving the transport roller The invention according to claim 2 or 3, further comprising: a torque limiter provided between the transport roller and the transport roller driving means, the torque limiter being provided between the nip portion center and the transport roller to apply front tension to the master. In addition to the effects described above, it is possible to reliably apply a fixed front tension to the master downstream of the platen roller in the master transport direction with a simple configuration.

According to the fifth aspect of the present invention, there is provided a master storage means for storing a master so as to be able to be fed out, and a back tension applying means for applying a back tension to the master between the master storage means and the platen roller. The back tension is made larger than the front tension, so that in addition to the effect of the invention according to claim 4, a higher back tension is given to the master on the side where the rotation of the platen roller enters, and the rotation of the platen roller enters. A slight slippage occurs between the master on the side and the platen roller, and the master moves uniformly downstream in the master transport direction. The master on the upstream side in the master transport direction may become loose, or may be installed, for example, on the downstream side in the master transport direction. The unconveyed plate with low conveyance resistance is pulled out by the master conveyance means, and the slack generated on the master on the upstream side in the master conveyance direction is promoted. For example, when using a master having a small thickness of a porous support or a master having no porous support as well as a conventional master, the occurrence of wrinkles can be prevented. Dimension reproducibility can be improved.

According to the sixth aspect of the present invention, the control means is based on a signal from the characteristic value detecting means for detecting a characteristic value of a master expansion / contraction-related factor affecting expansion / contraction of the master plate making dimension during plate making. In addition, by controlling the master hugging angle changing means so as to change the master hugging angle, in addition to the effects of the above-described inventions, the characteristic value of the master expansion / contraction-related factor detected by the characteristic value detecting means can be controlled to be larger or smaller. The master ’s hugging angle can be automatically changed accordingly.
It is possible to reliably prevent the master plate making dimension from changing due to the expansion or contraction of the master, and to further improve the image dimension reproducibility.

According to the seventh aspect of the present invention, the characteristic value detecting means comprises an image amount detecting means for detecting an amount of a plate making image. It works. According to the invention described in claim 8,
The characteristic value detecting means comprises temperature detecting means for detecting at least one of the internal and external temperatures of the plate making apparatus main body. Play.

According to the ninth aspect of the present invention, the characteristic value detecting means comprises humidity detecting means for detecting at least one of the inside and outside humidity of the plate making apparatus main body, so that the humidity level can be controlled. Accordingly, the effect of the invention described in claim 6 is exerted. According to the invention described in claim 10,
Since the characteristic value detecting means comprises a thermal head temperature detecting means for detecting the temperature of the thermal head, the effect of the invention according to claim 6 is exerted according to the level of the temperature of the thermal head.

According to the eleventh aspect of the present invention, the control means controls the master holding angle changing means so as to change the master holding angle based on each signal from at least two or more characteristic value detecting means. Accordingly, it is possible to respond more finely according to the magnitude, height, etc. of the characteristic value of the master expansion / contraction-related factor, thereby achieving the effect of the invention according to any one of claims 6 to 10.

According to the twelfth aspect of the present invention, the master on the downstream side of the platen roller in the master transport direction or the master made by plate-making is transported in a direction away from the thermal head. In addition to this, it is possible to prevent the master or the master made by plate making from being deformed due to the heat storage of the thermal head and the like, and furthermore to prevent the master from being wrinkled more reliably.

According to the thirteenth aspect, the first aspect is described.
Or a plate making and printing apparatus for winding a master made by the plate making apparatus on a plate cylinder, whereby a master winding on a plate cylinder is achieved. It is possible to prevent the occurrence of wrinkles and the like at the time of mounting, and to improve image size reproducibility.

[Brief description of the drawings]

FIG. 1 is a partially sectional front view of a plate making printing apparatus and a plate making apparatus showing an embodiment of the present invention.

FIG. 2 is an enlarged partial cross-sectional front view showing a main part of the plate making apparatus of FIG.

FIG. 3 is a partial cross-sectional front view showing a main part of a master holding angle varying unit of the plate making apparatus of FIG. 1;

FIG. 4 is a perspective view showing a further main part of the master angle-of-hold angle changing means of FIG. 3;

FIG. 5 is a block diagram showing a control configuration mainly around the plate making apparatus of the plate making printing apparatus of FIG. 1;

FIG. 6 is a plan view of a main part of the operation panel.

FIG. 7 is a partial cross-sectional front view of a main part showing the operation of the plate making apparatus of FIG. 1;

8A is a schematic front view illustrating the operation of the main part in the conventional plate making apparatus, and FIG. 8B is a schematic front view illustrating the operation of the main part in the plate making apparatus of FIG. It is a front view.

FIG. 9 is a front view of the thermal head showing a location of a head temperature sensor for detecting a temperature of the thermal head.

FIG. 10 is a graph illustrating a relationship between a temperature of a thermal head and a master holding angle.

FIG. 11 is a flowchart showing a main part of a plate making operation.

[Explanation of symbols]

Reference Signs List 1 plate cylinder 2 ink roller constituting ink supply means 8 master 8c master supporting member 9a, 9b lower / upper tension roller 10 platen roller 10a platen roller shaft 10b axial center of platen roller 11 thermal head 12a, 12b Transfer roller middle pair 27 Angle roller as displacement member 30 Temperature sensor as temperature detecting means 31 Humidity sensor as humidity detecting means 32 Head temperature sensor as thermal head temperature detecting means 33 First electromagnetic clutch as torque limiter 35 Transport roller First stepping motor as driving means 36 Back tension applying means 38 Front tension applying means 40 Operation panel 48 Image amount detecting means 50 Master holding angle varying means 55 Second step as displacement member driving means Controller 70 plate making apparatus 80 prepress printing apparatus F1 back tension F2 front tension Mb master contact boundary Nc nip center θa master embracing angle θb master separation angle X master conveying direction as ping motor 65 control means

Claims (13)

[Claims] 1. A plate making apparatus comprising: a thermal head for heating and making a master to be fed out according to image information; and a rotatable platen roller for moving the master to the downstream side in the master transport direction while pressing the master against the thermal head. In the apparatus, when viewed from the axial direction of the platen roller, a semi-line connecting the center of the nip between the thermal head and the platen roller and the axial center of the platen roller, and the master viewed from the axial direction of the platen roller. Is a master hugging angle which changes a master hugging angle formed by a master contact boundary contacting the outer peripheral surface of the platen roller on the downstream side of the nip portion center in the master transport direction and a half line connecting the axis center of the platen roller. A plate making apparatus having variable means. 2. The plate making apparatus according to claim 1, wherein the master holding angle varying means is disposed downstream of the platen roller in the master transport direction, and contacts the master downstream of the master transport direction. A plate making apparatus comprising: a displacement member capable of being displaced in a direction in which the master holding angle is changed; and a displacement member driving means for displacing the displacement member in a direction in which the master holding angle is changed. 3. The plate making apparatus according to claim 2, wherein said displacement member is a rotatable roller. 4. A plate-making apparatus according to claim 2, wherein said transfer roller is disposed downstream of said displacement member in said master transfer direction and moves said master downstream of said master transfer direction. And a torque limiter that is provided between the transport roller and the transport roller drive unit and that applies front tension to a master between the nip center and the transport roller. A plate making apparatus characterized by the above-mentioned. 5. A plate making apparatus according to claim 4, wherein a master storage means for storing the master so as to be able to be fed out, and a back tension application for applying a back tension to the master between said master storage means and said platen roller. Means, wherein the back tension is greater than the front tension. 6. A plate making apparatus according to claim 1, wherein said characteristic value detecting means detects a characteristic value of a master expansion / contraction-related factor affecting expansion / contraction of a master plate making dimension during plate making. And a control means for controlling the master holding angle varying means so as to change the master holding angle based on a signal from the characteristic value detecting means. 7. The plate making apparatus according to claim 6, wherein the characteristic value of the master expansion / contraction related factor is a plate making image amount formed on the master, and wherein the characteristic value detecting means detects the plate making image amount. A plate making apparatus comprising an amount detecting means. 8. The plate making apparatus according to claim 6, wherein the characteristic value of the master expansion / contraction-related factor is at least one of an internal temperature and an external temperature of the plate making apparatus main body. And a temperature detecting means for detecting at least one of the temperatures. 9. The plate making apparatus according to claim 6, wherein the characteristic value of the master expansion / contraction-related factor is at least one of humidity inside and outside the plate making apparatus main body, and And a humidity detecting means for detecting at least one of the humidity. 10. The plate making apparatus according to claim 6, wherein the characteristic value of the master expansion / contraction factor is a temperature of the thermal head, and the characteristic value detecting means detects a temperature of the thermal head. A printing device comprising a detection unit. 11. A plate making apparatus according to claim 6, wherein said control means determines said master holding angle based on each signal from at least two or more characteristic value detecting means. A plate making apparatus characterized in that the master holding angle changing means is controlled so as to change. 12. A plate making apparatus according to claim 1, wherein a master or a master made downstream of said platen roller in said master conveying direction is transported away from said thermal head. A plate making apparatus characterized in that the plate making is performed. 13. A plate cylinder having the above-described plate-making apparatus according to any one of claims 1 to 12, wherein a master made by the plate-making apparatus is wound, and ink is applied to the master on the plate cylinder. A plate-making printing apparatus comprising: an ink supply unit that supplies printing ink to a master on the plate cylinder to perform printing on the printing paper.