JP2017185704A - Plate making device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent sagging of a master caused when a thermal head is decompressed.SOLUTION: A plate making device comprises embracing means 12 comprising a tension application member 12a for applying tension to a master, and support members 12b provided at both ends of a thermal head 13a, in which rectangular support holes 12c elongated in a vertical direction are formed. When the thermal head is located at a compression position, an end part 12d of the tension application member 12a and an upper end part 12ca of the support hole 12c come into contact with each other to apply tension to a master at a predetermined embracing angle. When the thermal head 13a is located at a decompression position, the support member 12b moves upward as the thermal head 13a moves in a state in which the tension application member 12 is placed on the surface of the master, and thereby predetermined tension is always applied to the master from a time when it is set in the plate making device 1.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a plate making apparatus for making a plate-making image by thermally perforating a stencil sheet using a thermal head.

  Conventionally, a thermal head in which a large number of heating elements are arrayed and a film surface side of a belt-shaped heat-sensitive stencil sheet (hereinafter referred to as “master”) in which a thermoplastic resin film and a porous support are bonded together are press-contacted. In such a state, the thermal head and the master, each of which is driven to generate heat based on the image data, are moved relative to each other in the sub-scanning direction orthogonal to the main scanning direction, which is the arrangement direction of the heating elements, and the master responds to the image data. A plate making apparatus for forming a perforated image is known.

  Further, in Patent Document 1 below, when a long medium is transported in a belt shape, a tension is applied to the medium while bending the transport path of the medium, thereby absorbing the slack generated during transport and balancing the left and right tensions. A media transport mechanism that corrects and stabilizes the transport state is disclosed.

JP 2010-280472 A

  In the conventional plate making apparatus 100, as shown in FIG. 4A, a master roll 101 in which a long master is wound in a band shape and a plate making means 102 composed of a platen roller 102a and a thermal head 102b are provided. , A conveying guide means 103 for guiding the conveying direction of the master fed out from the master roll 101, a holding means 104 for maintaining the angle held by the platen roller 102a, and a pair of conveying rollers, and a pre-made master And conveying means 105 for conveying the latter to the subsequent stage.

  As shown in the figure, during plate making, the master is nipped between the platen roller 102a by pressurizing the thermal head 102b in a state in which the conveyance path of the master is bent and tension is applied by the conveyance guide means 103 and the holding means 104. By carrying it, the master punches heat-sensitive without wrinkles or skew.

  If the thermal head 102b is kept pressurized, the rubber platen roller 102a is unnecessarily deformed by the metal thermal head, so that the plate making process is completed as shown in FIG. 4B. Then, the thermal head 102b is depressurized and separated upward so that the pressurized state is released.

  By the way, in the general plate making apparatus 100, the thermal head 102b is provided with a holding roller serving as the holding means 104. When releasing the pressure state of the thermal head 102b, the thermal head 102b is moved from the platen roller 102a. By rotating in the separating direction, the application of tension to the master by the holding roller is also released simultaneously with the release of the pressure of the thermal head 102b.

  For this reason, when the pressurized state of the thermal head 102b is released, the tension applied to the master is also released, so that the master may be loosened. Therefore, when the next plate making process is performed after the plate making is finished, if the master is nipped in a slack state, the master is conveyed while being curled, causing wrinkles and skews.

  In order to solve such a problem, for example, it is assumed that the configuration of the media transport mechanism disclosed in Patent Document 1 is adopted. However, although the mechanism disclosed in Patent Document 1 has a function of correcting the wobbling of the master in the left and right conveyance direction, since both ends of the tension bar are supported from below, the thermal head is pressed. When the state is released, an appropriate tension cannot be applied to the master, and the above problem cannot be solved.

  Accordingly, the present invention has been made in view of the above-described problems, and provides a plate making apparatus capable of applying a predetermined tension to a set master even when the pressurized state of a thermal head is released. It is intended.

In order to achieve the above object, a first aspect according to the present invention includes a master roll in which a master is wound in a roll shape,
A thermal head in which heating elements are arranged, and a platen roller that is rotationally driven, and the master is nipped by the thermal head and the platen roller that have been moved from a reduced pressure position to a pressure position, and plate making is performed on the master. Plate making means for forming an image;
Tension applying means for applying tension to the master so that the master is held in the platen roller at a predetermined angle when the thermal head is in the decompression position;
Is a plate making apparatus.

  According to a second aspect of the present invention, in the plate making apparatus according to the first aspect, both ends of the supporting means extending in the master width direction orthogonal to the conveying direction of the master fed out from the master roll are suspended by elastic members. The plate making apparatus is provided with a conveyance guide unit that is provided and supports the master from the back side by the support unit and guides the conveyance of the master.

According to a third aspect of the present invention, in the plate making apparatus according to the first aspect or the second aspect, the tension applying unit includes:
A tension applying member extending in a master width direction orthogonal to the conveying direction of the master;
A support member that is provided at the master width direction side end of the thermal head, and that supports the end of the tension applying member with a support hole having a vertically long rectangle;
When the thermal head is in the pressure position, the upper end portion of the support hole and the end portion of the tension support member abut at a position where the master is held at a predetermined holding angle,
When the thermal head is in the reduced pressure position, the end of the tension applying member remains mounted on the surface of the master without coming into contact with the lower end of the support hole, It is a plate making device.

  According to the plate making apparatus according to the first aspect, even if the thermal head is moved from the pressurizing position to the depressurizing position, the tension applied to the master is maintained, so that it does not loosen. Therefore, even when the master is nipped by the thermal head and the platen roller at the next plate making, the master is prevented from curling at the nip point between the thermal head and the platen roller while suppressing the generation of wrinkles on the master. Can do.

  According to the plate making apparatus according to the second aspect, since both ends of the support means are provided in a state of being suspended by the elastic member, the axial direction of the support means is the vertical direction, the left-right direction, the diagonal direction, and the depth / front side direction. Therefore, it is possible to absorb the misalignment of the master transport path length caused by variations in the equipment configuration when assembling the plate making apparatus and maintain the master transport path length during the master transport substantially uniform.

  According to the plate making apparatus according to the third aspect, the support hole formed in the support member has a rectangular shape, and when the thermal head moves to the pressurizing position, the end of the tension applying member and the upper end of the support hole Since the positioning accuracy of the abutting position with the part increases, the tension is applied to the master so that it is always held at the holding angle suitable for the platen roller without moving the position of the tension applying member during plate making. The state can be maintained, and at the time of decompression, a state in which a tension is applied to the master can be maintained.

1 is a schematic perspective view of a plate making apparatus according to the present invention. It is a schematic perspective view which shows the conveyance guide means of the apparatus. (A) is a schematic block diagram when the thermal head of the same apparatus exists in a pressurization position, (b) is a schematic block diagram when the thermal head of the same apparatus exists in a pressure reduction position. (A) is a schematic block diagram at the time of plate making in the conventional plate making apparatus, (b) is a schematic block diagram at the time of nip cancellation | release in the apparatus.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings. In addition, the present invention is not limited by this embodiment, and all other forms, examples, operation techniques, and the like that can be considered by those skilled in the art based on this form are included in the scope of the present invention. Shall.

  In the present specification, in the following description with reference to the accompanying drawings, when the words “up”, “down”, “left”, and “right” are used to indicate directions and positions, this is shown in FIG. Matches top, bottom, left, and right.

  Further, in each figure, the master conveyance direction (for example, the horizontal direction from the right side to the left side in the figure in FIG. 3) is defined as “master conveyance direction A”, and the horizontal direction (for example, in FIG. A direction from the front side of the paper surface to the depth, which is the same as the rotation axis 15a of the master roll 15 and the axial direction of the transport roller in the transport means 14, is defined as “master width direction B”.

First, the configuration of the plate making apparatus 1 according to the present invention will be described with reference to FIGS.
The plate making apparatus 1 according to the present invention uses the plate making information acquired from the outside or the plate making information created from the image data obtained by reading the original to make the thermoplastic resin film and the porous support by the plate making means 13 described later. It is an apparatus for making a plate by thermally perforating a bonded heat-sensitive stencil sheet (hereinafter referred to as “master”) while carrying a nip along the master conveying direction A.

  As shown in FIG. 1, the plate making apparatus 1 includes a conveyance guide means 11, a holding means 12, a plate making means 13, and a conveyance means 14. For example, a plate making unit of a stencil printing apparatus which is a printing apparatus. As mounted. Further, on the upstream side of the plate making apparatus 1, a master roll 15, which is a roll-shaped master that is provided at a predetermined position so as to be rotatable and can be fed out, is provided.

  The conveyance guide means 11 is comprised by the support means 11a which makes a column shape longer than the width | variety of a master like a round bar or a roller, for example. In the present embodiment, a metal bar (hereinafter also referred to as “guide shaft 11a”) having a smooth surface is used as the support means 11a so as not to hinder the conveyance of the master. The guide shaft 11a is not limited to a metal bar as in the present embodiment, and may be made of resin. Even in such a configuration, it is preferable to smooth the surface so as not to hinder the conveyance of the master.

  The guide shaft 11a guides the conveyance of the master fed out from the master roll 15, and applies a predetermined tension to the master, so that the conveyance path between the plate making means 13 and the master roll 15 is bent. Arranged along the master width direction B orthogonal to the master transport direction A.

  Further, in the conventional apparatus, during the master conveyance, the conveyance direction of the master is shifted in the vertical direction or the master width direction B due to variations in the mounting positions of the master roll 15 and the plate making means 13 and variations in components on the conveyance path. Thus, there is a problem that the master transport path length from the master roll 15 to the plate making means 13 is shifted.

  Therefore, in the present invention, in order to absorb the deviation of the master conveyance path length caused by the variation in the equipment configuration at the time of assembling the apparatus and make the conveyance path length in the width direction of the master substantially uniform, as shown in FIG. Both ends of 11a are provided suspended by elastic members 11b (springs, rubber materials, etc.). Note that one end of the elastic member 11b is fixed to an attachment piece 1a or the like of the apparatus housing side plate as shown in FIG. 2, and expands and contracts in accordance with the state of the master using that as a fulcrum.

  By setting it as such a structure, a predetermined tension can be given, supporting the master extended | stretched from the master roll 15 from the back surface side, and a master will always be in the tensioned state. Further, since the elastic member 11b can freely expand and contract, the axial direction of the guide shaft 11a can be moved in the vertical direction, the horizontal direction, the diagonal direction, and the depth / front side in the drawing, so that the master transport path length can be increased. Therefore, the master conveyance path length can be maintained substantially uniform.

  The holding means (corresponding to “tension applying means” in the claims) 12 includes a tension applying member 12a made of a member longer than the length in the width direction of the master, such as a round bar or a roller having a cylindrical shape, for example. A support hole 12c for supporting both ends of the tension applying member 12a is formed, and the support member 12b moves relative to the tension applying member 12a.

  In the present embodiment, as shown in FIG. 1, the tension applying member 12a uses a round bar that is supported in a state where the end 12d is loosely inserted into the support hole 12c, and the master is the plate making apparatus 1. While being set, the master is held by the platen roller 13b at a predetermined holding angle. Further, while the master is set in the plate making apparatus 1, the master is placed on the master surface as a plate making surface, and a predetermined tension (back tension) is applied to the master by the weight of the tension applying member 12a. Functions as tension applying means. Therefore, the tension applying member 12a is disposed along the master width direction B at a position where the transport path between the transport guide unit 11 and the plate making unit 13 is bent.

  In addition, as a material of the round bar used as the tension applying member 12a, it is formed by using a relatively light metal such as aluminum or a general synthetic resin, and depending on the strength of the master, at least when placed. The weight is such that the master is not torn and a predetermined tension can be applied to the master. Further, since the tension applying member 12a is always in contact with the surface of the master set in the plate making apparatus 1, the surface is smoothly processed so as not to damage the surface of the master.

  As shown in FIGS. 3A and 3B, the support member 12b is assembled to both ends of the thermal head 13a in the master width direction B, and the thermal head 13a is located between the pressurization position and the decompression position. It moves with the movement. Further, the support member 12b is formed with a support hole 12c having a rectangular shape in the vertical direction, and the end 12d of the tension applying member 12a is inserted therein.

  As shown in FIG. 3A, the position when the upper end portion 12ca of the support hole 12c abuts the end edge of the end portion 12d of the tension applying member 12a at the time of plate making is appropriately held by the platen roller 13b. It is uniquely determined by the positional relationship with the platen roller 13b so as to hold the master at the insertion angle. However, if the support hole 12c is an ellipse or a long hole, the contact portion of the hole becomes a curved surface, so that the certainty of contacting the edge of the end portion 12d at a certain position is lowered depending on the processing accuracy. End up. Therefore, in the present invention, the shape of the support hole 12c is a rectangle, and the end edge of the end portion 12d is brought into contact with the fixed position.

  At the time of the plate making process by the plate making means 13, as shown in FIG. 3A, the thermal head 13a moves to the pressing position and nips the master with the platen roller 13b.

  At this time, as shown in the drawing, the shaft edge portion of the tension applying member 12a contacts the upper end portion 12ca of the support hole 12c while maintaining the contact state between the tension applying member 12a and the surface of the master. Accordingly, the tension applying member 12a is fixed in a state where a predetermined tension is applied to the master so that the master is held at a holding angle suitable for the platen roller 13b. Is transported at an appropriate position. Therefore, it is possible to prevent an unintended load from being applied to the master due to, for example, vibration of a printing apparatus on which the plate making apparatus 1 is mounted.

  When the plate making process by the plate making means 13 is completed, as shown in FIG. 3B, the thermal head 13a moves to the reduced pressure position, and the nip between the thermal head 13a and the platen roller 13b is released.

  At this time, as shown in the figure, the support member 12b moves as the thermal head 13a moves away from the platen roller 13b. However, since the movement of the support member 12b stops at a position where the lower end portion 12cb of the support hole 12c and the end edge of the end portion 12d do not contact each other, the state where the support member 12b is placed on the master is maintained. As a result, the thermal head 13a can be depressurized while a predetermined tension is applied to the master, and it is possible to suppress the looseness of the master that has occurred during the depressurization and the generation of wrinkles of the master at the time of re-making.

  The plate making means 13 includes a thermal head 13a in which a large number of heating elements are arranged in parallel in the master width direction B, and a platen roller 13b that conveys the master downstream while being rotationally driven at a predetermined speed. The plate making means 13 nips the master that is sequentially fed from the master roll 15 between the thermal head 13a and the platen roller 13b, and the image is generated by a heating element provided on the thermal head 13a while conveying the master in this nipped state. Thermally perforate the prepress image based on the data.

  When the thermal head 13a is in the pressurizing position, the support hole 12c is positioned at the end of the tension applying member 12a at a position where the upper end 12ca of the support hole 12c is held by the platen roller 13b at a predetermined holding angle. When the thermal head 13a is in contact with the portion 12d and the thermal head 13a is at the decompression position, the lower end portion 12cb of the support hole 12c needs to be formed so as not to contact the end portion 12d of the tension applying member 12a. Therefore, the size of the support hole 12c is appropriately defined by the movement distance between the pressure position of the thermal head 13a and the pressure reduction position, the master's holding angle to the platen roller 13b, and the like.

  The conveying unit 14 is a unit that conveys the master that has been subjected to plate making downstream. In the present embodiment, the master is configured by a pair of transport rollers that nip and transport the front and back surfaces of the master-making master. When this apparatus is installed as a plate making unit of a stencil printing apparatus that is a printing apparatus, the master-making master is transported by the transport means 14 to a printing drum that is a printing part.

  In the plate making apparatus 1 described above, first, the master fed out from the master roll 15 is fed out to the conveying means 14 and set.

  Next, in order to start the plate-making process, the thermal head 13a is moved from the reduced pressure position to the pressurized position, and the master is nipped by the thermal head 13a and the platen roller 13b. At this time, when the thermal head 13a is moved, the support member 12b is gradually lowered, and the tension applying member 12a is placed on the surface of the master.

  As shown in FIG. 3A, the placed tension applying member 12a is positioned so that the end edge of the end portion 12d abuts on the upper end portion 12ca of the support hole 12c as the support member 12b is lowered. Fixed. As a result, the master is held in the platen roller 13b at an appropriate holding angle.

  Further, when the plate making process is started from this state, the master is conveyed while absorbing the deviation of the master conveyance path length caused by the variation in the equipment configuration at the time of assembling the plate making apparatus 1 by the conveyance guide means 11, The master transport path length is transported to the plate making means 13 in a state where it is maintained substantially uniform.

  Next, when the master plate-making process is completed, the thermal head 13a is moved from the pressure position to the pressure reduction position. At this time, as the thermal head 13a moves, the support member 12b also moves upward. However, as shown in FIG. 3B, the tension applying member 12a is placed on the surface of the master and only the support member 12b. Moves upward. Thereby, since the thermal head 13a can be decompressed with the master stretched, it is possible to suppress wrinkles of the master that are likely to occur at the time of nip by the thermal head 13a at the next plate making.

  As described above, the plate making apparatus 1 described above is a hug constituted by a tension applying member 12a for applying tension to the master and the supporting members 12b in which the support holes 12c are formed and provided at both ends of the thermal head 13a. The means 12 functions as a tension applying means for always applying a predetermined tension to the master.

  For this reason, even if the thermal head 13a is moved from the pressurizing position to the depressurizing position, the state in which the tension is applied to the master is maintained, so that the thermal head 13a is not loosened. Therefore, even if the master is nipped by the thermal head 13a and the platen roller 13b at the next plate making, the master is curled at the nip point between the thermal head 13a and the platen roller 13b while suppressing the generation of wrinkles on the master. Can be prevented.

  Moreover, since the conveyance guide means 11 is provided in a state where both ends of the guide shaft 11a are suspended by the elastic member 11b, the axial direction of the guide shaft 11a is in the vertical direction, the horizontal direction, the diagonal direction, and the depth / front side direction. Each of them can be moved, and the master transport path length deviation at the time of master transport can be maintained substantially uniform by absorbing the deviation of the master transport path length caused by variations in the equipment configuration during assembly of the plate making apparatus 1.

  Further, the support hole 12c formed in the support member 12b of the holding means 12 has a rectangular shape, and when the thermal head 13a moves to the pressurizing position, the end 12d of the tension applying member 12a and the support hole 12c Since the positioning accuracy of the contact position with the upper end portion 12ca is high, the position of the tension applying member 12a does not move even during plate making, and the master is always held at a holding angle suitable for the platen roller 13b. The state where the tension is applied can be maintained.

1 ... Plate making apparatus (1a ... Mounting piece)
11 ... Conveyance guide means (11a ... Support means (guide shaft), 11b ... Elastic member)
12 ... Embrace means functioning as tension applying means (12a ... tension applying member, 12b ... support member, 12c ... support hole, 12ca ... upper end portion of support hole, 12cb ... lower end portion of support hole, 12d ... end portion)
13. Plate making means (13a ... thermal head, 13b ... platen roller)
14 ... Conveying means

Claims (3)

A master roll in which the master is wound into a roll,
A thermal head in which heating elements are arranged, and a platen roller that is rotationally driven, and the master is nipped by the thermal head and the platen roller that have been moved from a reduced pressure position to a pressure position, and plate making is performed on the master. Plate making means for forming an image;
Tension applying means for applying tension to the master when the thermal head is in the reduced pressure position;
A plate making apparatus characterized by comprising: Both ends of a support means extending in the master width direction orthogonal to the transport direction of the master fed out from the master roll are provided by being suspended by elastic members, and the master is transported by supporting the master from the back side by the support means. 2. The plate making apparatus according to claim 1, further comprising conveying guide means for guiding. The tension applying means includes
A tension applying member extending in a master width direction orthogonal to the conveying direction of the master;
A support member that is provided at the master width direction side end of the thermal head, and that supports the end of the tension applying member with a support hole having a vertically long rectangle;
When the thermal head is in the pressure position, the upper end portion of the support hole and the end portion of the tension support member abut at a position where the master is held at a predetermined holding angle,
The end of the tension applying member remains mounted on the surface of the master without contacting the lower end of the support hole when the thermal head is in the reduced pressure position. Item 3. A plate making apparatus according to item 1 or 2.

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