JP3779177B2 - Ink supply mechanism of printing apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
In the present invention, an upper space formed by an ink supply roll and an ink film thickness regulating member disposed in the vicinity thereof is used as an ink reservoir, and the ink in the ink reservoir is rotated by the ink supply roll. The present invention relates to an ink supply mechanism of a printing apparatus in which a constant amount of ink is continuously supplied by regulating through a gap.
[0002]
[Prior art]
FIG. 5 shows an overall schematic configuration diagram of a conventional stencil printing apparatus capable of duplex printing. As shown in FIG. 5, the stencil printing apparatus 100 includes upstream and downstream plate-making units 104 and 105 that perform thermal perforation by the thermal heads 102 and 103 on the stencil sheet 101 based on the respective image data, and the upstream side. The stencil sheet 101 made by the plate making unit 104 is wound and mounted on the upstream plate cylinder 106, and the fed printing paper 107 is pressed and conveyed between the plate cylinder 106 and the pressing roll 108. The upstream printing unit 109 that performs ink transfer on the upper surface (one surface) of the printing paper 107, the paper feeding unit 110 that feeds the printing paper 107 to the upstream printing unit 109, and the printing paper of the upstream printing unit 109 An upstream belt conveyance mechanism 111 that is disposed on the discharge side of 107 and conveys the printing paper 107 downstream by the movement of the belt 121, and a stencil sheet 101 made by the downstream plate making unit 105 The printing paper 107 wound around and attached to the flow-side plate cylinder 112 and fed by the upstream belt conveyance mechanism 111 is pressed and conveyed between the plate cylinder 112 and the pressing roll 114. A downstream printing unit 115 that performs ink transfer to the lower surface (the other surface), and the downstream printing unit 115 is disposed on the discharge side of the printing paper 107, and the printing paper 107 is moved downstream by the movement of the belt 122. And a downstream belt conveyance mechanism 117 that conveys the toner.
[0003]
Ink supply mechanisms B1 and B2 are provided in the plate cylinders 106 and 112 of the upstream and downstream printing units 109 and 115, respectively. Each of the ink supply mechanisms B1 and B2 includes an ink supply roll 123 that is in contact with the inner surfaces of the outer peripheral walls 106a and 112a of the plate cylinders 106 and 112, and a doctor roll 124 that is disposed on the ink supply roll 123 via a predetermined gap. And an ink distributor 125 for supplying ink between both the rolls 123 and 124, and the ink supply roll 123 is connected to the inner peripheral surfaces of the outer peripheral walls 106a and 112a in conjunction with the rotation of the plate cylinders 106 and 112. It is comprised so that rotation may be carried out. When the ink supply roll 123 rotates together with the rotation of the plate cylinders 106 and 112, ink with a certain film thickness adheres to the outer peripheral surface of the ink supply roll 123 through the gap with the doctor roll 124, and this adhered ink is The ink is always supplied to the inner surface side of the stencil sheet 101 by being transferred to the outer peripheral walls 106a and 112a.
[0004]
Next, the duplex printing operation will be briefly described. The plate cylinders 106 and 112 are rotated, and the printing paper 107 is fed from the paper feeding unit 110 to the upstream plate cylinder 106 in synchronization with the rotation. The fed printing sheet 107 is pressed against the stencil sheet 101 of the plate cylinder 106 by a pressing roll 108, whereby an ink image is transferred to the upper surface of the printing sheet 107. The printed sheet 107 printed on the upper surface is transferred to the plate cylinder 106. It is peeled off from the outer peripheral surface and guided to the upstream belt conveyance mechanism 111. The upstream belt conveyance mechanism 111 conveys the printing paper 107 by the movement of the belt 121 with the lower surface of the printing paper 107 as a contact surface, and is fed to the plate cylinder 112 downstream from the most downstream side of the belt 121. The fed printing sheet 107 is pressed against the stencil sheet 101 of the plate cylinder 112 by a pressing roll 114, whereby an ink image is transferred to the lower surface of the printing sheet 107. It is peeled off from the outer peripheral surface and guided to the downstream belt conveyance mechanism 117. The downstream belt conveyance mechanism 117 conveys the printing paper 107 by the movement of the belt 122 and is discharged from the most downstream side of the belt 122 to the paper discharge tray 116. The printing paper 107 discharged to the paper discharge tray 116 is placed in a stacked state here.
[0005]
A similar technique relating to the stencil printing apparatus 100 is disclosed in JP-A-8-90893.
[0006]
[Problems to be solved by the invention]
In the stencil printing apparatus 100 for double-sided printing, the upstream plate cylinder 106 is disposed on the upper side and the downstream plate cylinder 112 is disposed on the lower side with respect to the sheet conveyance path, and Since the ink supply roll 123 in the cylinders 106 and 112 is disposed opposite to the pressing rolls 108 and 114 for the reason of applying an appropriate printing pressure, the upstream ink supply mechanism B1 is disposed in the plate cylinder 106. At the lower end position, the downstream ink supply mechanism B2 is disposed at the upper end position in the plate cylinder 112, respectively. An upper space formed by each of the ink supply rolls 123 and the doctor rolls 124 disposed in the vicinity thereof serves as an ink reservoir 130 (shown in FIG. 6), and the ink reservoir 130 has the above-described printing operation. Even after the completion of the process, the state where the ink 131 is stored is maintained, so that the next printing operation can be immediately handled. However, the ink 131 stored in the ink reservoir 130 may hang down due to its own weight from the gap between the ink supply roll 123 and the doctor roll 124. In particular, the ink 131 is likely to occur when the viscosity of the ink 131 to be used is low, or when the ink 131 is left unused for a long time and the ink viscosity is lowered due to a composition change.
[0007]
Here, the dripping of the ink in the upstream plate cylinder 106 falls to the inner peripheral surface of the outer peripheral wall 106a of the plate cylinder 106 positioned immediately below, but in the upstream plate cylinder 112. This dripping of ink causes a problem that the plate cylinder 112 becomes dirty because a large number of members are actually stored in the plate cylinder 112.
[0008]
In order to solve such a problem caused by ink dripping, it is conceivable to provide an ink receiving member 132 at a position below the gap between the ink supply roll 123 and the doctor roll 124 as shown in FIG. However, when the ink receiving member 132 is provided in the plate cylinder 112, the operation of removing the accumulated ink is troublesome.
[0009]
In the above-described conventional example, the stencil printing apparatus 100 that has two printing portions and performs duplex printing has been described. When it is necessary to arrange the above, the same problem as described above occurs.
[0010]
Accordingly, the present invention has been made to solve the above-described problem, and in the case where a plate cylinder is disposed below the paper conveyance path, the ink supply roll and the ink film thickness regulating member are disposed between It is an object of the present invention to provide an ink supply mechanism of a printing apparatus that can prevent contamination due to ink dripping from a gap and does not require an ink removal operation.
[0011]
[Means for Solving the Problems]
  According to a first aspect of the present invention, a desired ink is disposed between an ink supply roll disposed inside a plate cylinder and rotating with the plate cylinder while being in contact with the inner peripheral surface of the plate cylinder, and an outer peripheral surface of the ink supply roll. An ink film thickness regulating member that is disposed in close proximity via a gap, and an upper space constituted by the outer peripheral surfaces of the ink film thickness regulating member and the ink supply roll on the side close to each other is defined as an ink reservoir, Of the ink stored in the ink reservoir, the ink that adheres to the outer peripheral surface of the ink supply roll is regulated through the gap with the ink film thickness regulating member by the rotation of the ink supply roll. In an ink supply mechanism of a printing apparatus in which an ink film thickness adhering to an outer peripheral surface is constant and continuously supplied to an inner peripheral surface of the plate cylinder, the ink supply roll An ink recovery means for returning the ink dropping from the gap between the serial ink film thickness regulating member on the outer circumferential surface of the inking rollThe ink collecting means spans an ink receiving position for receiving ink falling from the gap and an ink passing position for transferring ink in proximity to the outer peripheral surface of the ink supply roll, and from the ink receiving position to the ink receiving position. It is an ink collection plate that is arranged to be inclined downward toward the transfer position.It is characterized by that.
[0012]
  In the ink supply mechanism of this printing apparatus, the ink dripping from the gap between the ink supply roll and the ink film thickness regulating member is returned to the ink supply roll by the ink recovery means.In particular, an ink recovery plate may be disposed at a predetermined position as the ink recovery means.
[0013]
  According to a second aspect of the present invention, there is provided an ink supply mechanism of the printing apparatus according to the first aspect, wherein the inkThe gap between the location of the ink recovery plate serving as the transfer position and the outer peripheral surface of the ink supply roll was set larger than the gap between the ink supply roll and the ink film thickness regulating member.It is characterized by that.
[0014]
  In the ink supply mechanism of this printing apparatus, in addition to the operation of the invention of claim 1, the ink supply mechanismThe ink is delivered without adversely affecting the ink having a certain film thickness adhering to the outer peripheral surface of the supply roll.
[0015]
  The invention of claim 3An ink supply roll that is arranged inside the plate cylinder and rotates with the plate cylinder while being in contact with the inner peripheral surface of the plate cylinder and an outer peripheral surface of the ink supply roll are arranged in close proximity via a desired gap. An ink space regulating member, and an upper space formed by the outer peripheral surfaces of the ink film thickness regulating member and the ink supply roll adjacent to each other is defined as an ink reservoir, and is stored in the ink reservoir. Ink film that adheres to the outer peripheral surface of the ink supply roll by regulating the ink that adheres to the outer peripheral surface of the ink supply roll through the gap with the ink film thickness regulating member by rotation of the ink supply roll The thickness is kept constant and continuously supplied to the inner peripheral surface of the plate cylinder.Ink supply mechanism of printing apparatussmellAndInk recovery means is provided for returning ink falling from the gap between the ink supply roll and the ink film thickness regulating member to the outer peripheral surface of the ink supply roll.The ink collecting means has both an ink receiving position for receiving ink falling from the gap and an ink passing position for transferring ink in the vicinity of the outer peripheral surface of the ink supply roll, and an outer periphery serving as the ink receiving position. An ink collection roll disposed so as to be inclined downward from a surface portion toward an outer peripheral surface portion serving as the ink transfer position.Thus, the gap between the ink collecting roll and the outer peripheral surface of the ink supply roll that becomes the ink delivery position is set larger than the gap between the ink supply roll and the ink film thickness regulating member.It is characterized by that.
[0016]
  In the ink supply mechanism of this printing device,IAn ink collecting roll may be disposed at a predetermined position as the ink collecting means. Moreover, if the axis | shaft of an ink collection | recovery roll is aligned, it will be easily arrange | positioned in a predetermined position.In particular, the ink is delivered without adversely affecting the ink having a certain thickness attached to the outer peripheral surface of the ink supply roll.
[0017]
According to a fourth aspect of the present invention, there is provided the ink supply mechanism of the printing apparatus according to the third aspect, wherein the ink collecting roll has an outer peripheral surface serving as the ink delivery position, with an upstream surface being the ink receiving position. It is made to rotate in the rotation direction which makes this location downstream.
[0018]
In the ink supply mechanism of this printing apparatus, in addition to the operation of the invention of claim 3, rapid ink recovery is possible.
[0025]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
[0026]
1 and 2 show a first embodiment of the present invention. FIG. 1 is an overall schematic configuration diagram of a stencil printing apparatus, and FIG. 2 is a configuration diagram of an ink supply mechanism disposed in a downstream plate cylinder.
[0027]
As shown in FIG. 1, a digital stencil printing apparatus (printing apparatus) 1 includes a document reading unit (not shown), an upstream plate making unit 2 and a downstream plate making unit 3, an upstream printing unit 4 and a downstream printing unit. 5, a paper feed unit 6, an upstream belt conveyance mechanism 7 and a downstream belt conveyance mechanism 8, a paper discharge unit 9, an upstream plate discharge unit 10, and a downstream plate discharge unit 11.
[0028]
The document reading unit includes, for example, an automatic document feed reading unit and a document placement reading unit. The automatic document feeding / reading unit includes an obliquely inclined document inclined plate for placing an original, a pair of original conveying rolls for conveying the original placed on the original inclined plate, and converting the content of the conveyed original into an electric signal. And a line image sensor for reading. This line image sensor is also used as a document placement reading unit.
[0029]
The document placement reading unit is disposed below the document placement glass table, a horizontal document placement glass table on which the document is placed, a pressure plate provided on the document placement glass table so as to be openable and closable. It has a guide belt that moves by the driving force of the motor, and a line image sensor that moves below the document placement glass table by the guide belt.
[0030]
The line image sensor reads the original conveyed by the original conveying roll as the original of the automatic original feeding reading unit. The original on the original placement reading unit moves while the line image sensor is guided by the guide belt, and reads the image information described on the original.
[0031]
The upstream side plate making unit 2 includes a base paper storage unit 21 that stores a long stencil base paper 20 formed in a roll shape, and a writing disposed downstream of the base paper storage unit 21 in the transport direction of the stencil base paper 20 A thermal head 22 which is a head, a platen roll 23 which is disposed at a position opposite to the thermal head 22 and is rotated by a driving force of a pulse motor (not shown), and transport of the stencil sheet 20 to the platen roll 23 and the thermal head 22 A pair of base paper feed rolls 24, 24 disposed downstream in the direction and rotated by the driving force of the pulse motor, and a pair of base paper feed rolls 25, 25 disposed further downstream of the pair of base paper feed rolls 24, 24. And a base paper cutter 26 disposed downstream of the pair of base paper feed rolls 25, 25. The thermal head 22 has a plurality of dot-like heating elements arranged in the direction perpendicular to the conveying direction of the stencil sheet 20, and in this embodiment, the maximum printing sheet is A3, and thus the dot-like heating element over the range of A3 width. Is arranged.
[0032]
Then, the stencil sheet 20 is conveyed by the rotation of the platen roll 23 and the base paper feed roll 24, and each point-like heating element of the thermal head 22 is selected based on the image data corresponding to the upper surface (one surface) side read by the line image sensor. The stencil sheet 20 is thermally perforated by making a heat generation operation, and the stencil sheet 20 having a predetermined length is created by cutting the downstream portion of the stencil sheet 20 with the base paper cutter 26.
[0033]
The downstream side plate making unit 3 includes a base paper storage unit 31 that stores a long stencil base paper 20 formed in a roll shape, and a writing head that is disposed downstream of the base paper storage unit 31 in the conveying direction of the stencil base paper 20. , A platen roll 33 which is disposed at a position opposite to the thermal head 32 and is rotated by a driving force of a pulse motor (not shown), and a conveying direction of the stencil sheet 20 with respect to the platen roll 33 and the thermal head 32 A pair of base paper feed rolls 34 and 34 that are arranged downstream of the pair of motors and rotated by a driving force of a pulse motor, and a pair of base paper feed rolls 35 and 35 that are further arranged downstream of the pair of base paper feed rolls 34 and 34. , And a base paper cutter 36 disposed downstream of the pair of base paper feed rolls 35 and 35. The thermal head 32 has a plurality of dot-like heating elements arranged in the direction perpendicular to the conveying direction of the stencil sheet 20, and in this embodiment, the maximum printing sheet is A3, so that the dot-like heating element covers the range of A3 width. Is arranged.
[0034]
Then, the stencil sheet 20 is conveyed by the rotation of the platen roll 33 and the base paper feed roll 34, and each point-like heating element of the thermal head 32 is selected based on the image data corresponding to the lower surface (the other surface) read by the line image sensor. The stencil sheet 20 is thermally perforated by making a heat generation operation, and the stencil sheet 20 having a predetermined length is created by cutting the downstream portion of the stencil sheet 20 by the base paper cutter 36.
[0035]
The upstream printing unit 4 is composed of an ink-permeable member having a porous structure and an outer peripheral wall 40a. The outer peripheral wall 40a is rotated in the direction of arrow A in FIG. 1 by the driving force of a main motor (not shown). 40 and a clamp portion 41 which is provided on the outer peripheral wall 40a of the plate cylinder 40 and clamps the front end of the stencil sheet 20.
[0036]
The upstream printing unit 4 is provided with an upstream ink supply mechanism A1 inside the plate cylinder 40. The upstream ink supply mechanism A1 includes an ink supply roll 42 that contacts the inner peripheral surface of the outer peripheral wall 40a of the plate cylinder 40, and an ink film thickness regulating member that is disposed on the ink supply roll 42 via a predetermined gap. And a substantially wedge-shaped upper space formed by the doctor roll 43 and the outer peripheral surfaces of the two rolls 42, 43 adjacent to each other is used as an ink reservoir 81, and the ink 82 is supplied to the ink reservoir 81. And an ink drive rod 45 which is disposed in the ink reservoir 81 and is driven to rotate.
[0037]
Further, the upstream printing unit 4 includes a pressing roll 46 disposed outside the outer peripheral wall 40 a of the plate cylinder 40 and at a position facing the ink supply roll 42, and the pressing roll 46 is connected to the outer peripheral wall of the plate cylinder 40. There is a pressing pressure means (not shown) that moves to a pressing position (solid line position in FIG. 1) for pressing to 40a and a separating position (virtual line position in FIG. 1) spaced from the outer peripheral wall 40a of the plate cylinder 40. The press roll 46 changes between the press position and the separation position in conjunction with the rotation of the plate cylinder 40 during printing, and passes through the printing paper 45 that is a printing medium conveyed in synchronization with the rotation of the plate cylinder 40. It is sometimes positioned at the pressing position, and at other times (when the printing paper 45 is not passed), it is positioned at the separated position.
[0038]
Then, the tip of the stencil sheet 20 conveyed from the upstream plate making unit 2 is clamped by the clamp unit 41, and the plate cylinder 40 is rotated in this clamped state so that the stencil sheet 20 is wound around the outer peripheral wall 40a of the plate cylinder 40 and attached. The stencil sheet 20 is applied to the upper surface (one surface) of the printing paper 45 by pressing the printing paper 45 conveyed in synchronization with the rotation of the printing cylinder 40 against the stencil paper 20 of the printing cylinder 40 by the pressing roll 46. The ink 82 is transferred from the perforated portion of the ink and an image is printed.
[0039]
The downstream printing section 5 is composed of an ink-permeable member having a porous structure and an outer peripheral wall 50a. The outer peripheral wall 50a is rotated in the direction of arrow B in FIG. 1 by the driving force of a main motor (not shown). 50 and a clamp portion 51 that is provided on the outer peripheral wall 50a of the plate cylinder 50 and clamps the front end of the stencil sheet 20.
[0040]
Further, the downstream printing unit 5 is provided with a downstream ink supply mechanism A <b> 2 inside the plate cylinder 50. The downstream ink supply mechanism A2 includes an ink supply roll 52 that contacts the inner peripheral surface of the outer peripheral wall 50a, and a doctor roll that is an ink film thickness regulating member disposed on the ink supply roll 52 via a predetermined gap. 53 and an approximately wedge-shaped upper space formed by the outer peripheral surfaces on the sides close to each other between the rolls 52 and 53 are used as an ink reservoir 81 (shown in FIG. 2). Ink distributor 54 that supplies ink, ink drive rod 55 that is disposed in ink reservoir 81 and is driven to rotate, and ink 82 that drops from the gap between ink supply roll 52 and doctor roll 53 are supplied to ink supply roll 52. And an ink collecting means 83 for returning to the outer peripheral surface of the ink.
[0041]
Further, the downstream printing unit 5 includes a pressing roll 56 disposed outside the outer peripheral wall 50 a of the plate cylinder 50 and at a position facing the ink supply roll 52, and this pressing roll 56 is connected to the outer peripheral wall of the plate cylinder 50. A pressing pressure means (not shown) that moves to a pressing position that presses against 50a (solid line position in FIG. 1) and a separating position that is separated from the outer peripheral wall 50a of the plate cylinder 50 (virtual line position in FIG. And a liquid application roll 70 that applies silicone oil, which is a liquid, to the outer peripheral surface of the pressing roll 56. The press roll 56 changes between the pressing position and the separation position in conjunction with the rotation of the plate cylinder 50 during printing, and passes through the printing paper 45 that is a printing medium conveyed in synchronization with the rotation of the plate cylinder 50. It is sometimes positioned at the pressing position, and at other times (when the printing paper 45 is not passed), it is positioned at the separated position. The liquid application roll 70 may be provided so as to rotate with the rotation of the pressing roll 56, or may be provided so as not to rotate even when the pressing roll 56 rotates. Further, although silicone oil is used as the liquid, it may be liquid that does not exhibit color by contact between the printing paper 45 and the pressing roll 56, and may be water or the like.
[0042]
Then, the front end of the stencil sheet 20 conveyed from the downstream side plate making unit 3 is clamped by the clamp unit 51, and in this clamped state, the plate cylinder 50 is rotated so that the stencil sheet 20 is wound around the outer peripheral wall 50a of the plate cylinder 50. The stencil sheet 20 is applied to the lower surface (the other surface) of the printing paper 45 by pressing the printing paper 45 conveyed in synchronization with the rotation of the printing cylinder 50 against the stencil paper 20 of the printing cylinder 50 by the pressing roll 56. The ink 82 is transferred from the perforated portion of the ink and an image is printed.
[0043]
The paper feed unit 6 includes a paper feed stand 57 on which the print paper 45 as a print medium is stacked, a primary paper feed roll 58 that moves only the uppermost print paper 45 from the paper feed stand 57, and the primary paper feed. A pair of secondary paper feed rolls 59 are provided to convey the printing paper 45 moved by the roll 58 between the plate cylinder 40 and the pressing roller 46 in synchronization with the rotation of the upstream plate cylinder 40. The primary paper feed roll 58 and the secondary paper feed roller 59 are configured to selectively transmit the rotation of a main motor (not shown) via each paper feed clutch.
[0044]
The upstream belt conveyance mechanism 7 receives the printing paper 45 discharged from the upstream printing unit 4, conveys the received printing paper 45 to the front of the downstream printing unit 5, and feeds it to the downstream printing unit 5. Is. The upstream belt conveyance mechanism 7 sucks a pair of belt hanging members 60a and 60b, a belt 62 hung between the pair of belt hanging members 60a and 60b, and a conveyance surface side of the printing paper 45 of the belt 62. A suction box 63 and a suction fan 64, and belt driving means (not shown) that rotationally drives the belt 62 via the belt hooking member 60a (or 60b). The upstream belt conveyance mechanism 7 conveys the printing paper 45 by its own movement while sucking the printing paper 45 with the belt 62 as a contact surface opposite to the printing surface immediately before the printing paper 45.
[0045]
The downstream belt conveyance mechanism 8 receives the printing paper 45 discharged from the downstream printing unit 5 and conveys the received printing paper 45 to the paper discharge unit 9, and includes a pair of pulleys 66a and 66b, A belt 67 hung between a pair of pulleys 66a and 66b, a suction box and a suction fan (both not shown) for sucking the conveying surface side of the printing paper 45 of the belt 67, and the pulley 66a (or 66b) Belt driving means (not shown) for rotationally driving the belt 67 via the belt. The downstream belt conveyance mechanism 8 conveys the printing paper 45 by its own movement while the belt 67 sucks the printing paper 45.
[0046]
The paper discharge unit 9 has a paper discharge table 71 arranged at a dropping position of the printed print paper 45 conveyed by the downstream belt conveyance mechanism 8, and the print paper 45 is stacked on the paper discharge table 71. Place in state.
[0047]
The upstream side stencil unit 10 transports the stencil sheet 20 while the front end of the stencil sheet 20 wound around the upstream side plate cylinder 40 is released from the clamp, and the stencil sheet 20 released from the clamp is peeled off from the plate cylinder 40. A pair of discharging rolls 72 and 72 and a discharging box 73 for storing the stencil sheet 20 conveyed by the pair of discharging rolls 72 and 72 are provided.
[0048]
The downstream side stencil unit 11 transports the stencil sheet 20 while the front end of the stencil sheet 20 wound around the downstream side plate cylinder 50 is released from the clamp, and the stencil sheet 20 released from the clamp is peeled off from the plate cylinder 50. A pair of plate discharge rolls 74, 74 and a plate discharge box 75 for storing the stencil sheet 20 conveyed by the pair of plate discharge rolls 74, 74 are provided.
[0049]
Next, the configuration of the ink collection unit 83 provided in the downstream ink supply mechanism A2 will be described. As shown in FIG. 2, the ink recovery means 83 is an ink receiving position a (substantially a vertical line V1 passing through the gap d2) that can receive the ink 82 falling from the gap d2 between the ink supply roll 52 and the doctor roll 53. The upper position) and the ink transfer position b where the ink 82 can be transferred in the vicinity of the outer peripheral surface of the ink supply roll 52, and is inclined downward from the ink receiving position a toward the ink transfer position b. The ink collecting plate 84 is disposed obliquely below the ink supply roll 52 and the doctor roll 53.
[0050]
The gap d1 between the location of the ink collection plate 84 that becomes the ink transfer position b and the outer peripheral surface of the ink supply roll 52 is set to be at least larger than the gap d2 between the ink supply roll 52 and the doctor roll 53. . The size of the gap d1 is variable depending on the viscosity, temperature, etc. of the ink 82, but is set to a limit of about 10 times the size of the gap d2. Further, the ink delivery position a is arranged to be higher than the lowest end position H1 of the ink supply roll 52.
[0051]
Next, plate making and printing operations of the stencil printing apparatus 1 will be described. When the plate making mode is selected, it is checked whether or not the stencil sheet 20 is wound around the plate cylinders 40 and 50. If the stencil sheet 20 is mounted, the stencil sheet 20 is removed from the plate cylinders 40 and 50. Discard them in the discharge boxes 73 and 75, respectively.
[0052]
When the plate removal process is completed, thermal piercing is performed on the stencil sheet 20 by the thermal head 22 based on the image data corresponding to the upper surface side read by the original reading operation. Then, a plate-making process is performed in which the stencil sheet 20 thus made is wound around the upstream plate cylinder 40 and the upstream plate-making operation is completed. Further, thermal piercing is performed on the stencil sheet 20 by the thermal head 32 based on the read image data corresponding to the lower surface side. Then, a plate making process is performed in which the stencil sheet 20 thus made is wound around the downstream plate cylinder 50 and the downstream plate making operation is completed.
[0053]
Next, when the print mode is selected, it is checked whether or not there is a print sheet 45 on the paper feed tray 57. If there is no print sheet 45, a paper out error process is performed. Further, it is checked whether or not the stencil sheet 20 is fixed on each of the plate cylinders 40 and 50. If the stencil sheet 20 is not fixed, an error process without a plate is performed. Further, it is checked whether or not there is ink 82 in the ink reservoir 81 between the ink supply rolls 42 and 52 and the doctor rolls 43 and 53, and if there is no ink 82, no ink error processing is performed.
[0054]
When all of these checks are passed, the main motor rotates and the plate cylinders 40 and 50 rotate. The ink supply rolls 42 and 52 rotate together with the plate cylinders 40 and 50, and the ink 82 is continuously supplied to the plate cylinders 40 and 50 from the ink supply mechanisms A1 and A2. Further, in synchronization with the rotation of the plate cylinders 40 and 50, the printing paper 45 is fed from the paper feed unit 6 to the upstream plate cylinder 40. The fed printing paper 45 is pressed against the stencil sheet 20 of the plate cylinder 40 by the pressing roll 46, whereby an ink image is transferred to the upper surface of the printing paper 45. It is peeled off from the outer peripheral surface and guided to the upstream belt conveyance mechanism 7.
[0055]
The upstream belt conveyance mechanism 7 conveys the printing paper 45 by the movement of the belt 62 with the lower surface of the printing paper 45 as a contact surface, and is fed to the plate cylinder 50 downstream from the most downstream side of the belt 62. The fed printing paper 45 is pressed against the stencil sheet 20 of the plate cylinder 50 by a pressing roll 56 through a belt 67, whereby an ink image is transferred to the lower surface of the printing paper 45, and the lower-side printed printing paper 45 is printed. Is peeled off from the outer peripheral surface of the plate cylinder 50 and guided to the downstream belt conveyance mechanism 8. The downstream side belt conveyance mechanism 8 conveys the printing paper 45 by the movement of the belt 67, and is discharged from the most downstream side of the belt 67 to the paper discharge table 71. The printing paper 45 discharged onto the paper discharge tray 71 is placed in a stacked state here.
[0056]
Next, the operation of the ink supply mechanisms A1 and A2 will be described. When the ink 82 is supplied from the ink distributors 44 and 54 to the ink reservoirs 81, the ink 82 is agitated by the ink drive rods 45 and 55 so as to easily adhere to the outer peripheral surfaces of the ink supply rolls 42 and 52. The Of the agitated ink 82, the ink 82 adhering to the outer peripheral surface of the ink supply rolls 42 and 52 tends to rotate together with the rotation of the ink supply rolls 42 and 52 due to its adhesiveness. Then, those that cannot pass through the gap between the doctor rolls 43 and 53 are separated from the outer peripheral surface of the ink supply rolls 42 and 52, and only those that can pass through the gap continue to adhere to the outer peripheral surface of the ink supply rolls 42 and 52. become. That is, by passing through the gap between the doctor rolls 43 and 53, only the ink 82 having a predetermined film thickness always adheres to the ink supply rolls 42 and 52. The ink 82 adhering to the ink supply rolls 42 and 52 is transferred to the outer peripheral walls 40a and 50a where the ink supply rolls 42 and 52 are in close contact with the outer peripheral walls 40a and 50a of the plate cylinders 40 and 50.
[0057]
By the way, even after the above-described printing operation is completed, the state where the ink 82 is stored in each ink reservoir 81 of the ink supply rolls 42 and 52 and the doctor rolls 43 and 53 is maintained, and the next printing is performed. It can respond to the action immediately. In some cases, the ink 82 in each ink reservoir 81 hangs down from the gap between the ink supply rolls 42 and 52 and the doctor rolls 43 and 53. In particular, it is likely to occur when the viscosity of the ink 82 to be used is low, or when the ink 82 is left unused for a long time and the ink viscosity is lowered due to a composition change.
[0058]
The ink 82 that hangs down from the gap of the upstream ink supply mechanism A1 is located immediately below the outer peripheral wall 40a of the plate cylinder 40. Therefore, the outer peripheral wall 40a of the plate cylinder 40 is not contaminated. Fall into.
[0059]
Further, as shown in FIG. 2, the ink 82 dripping from the gap of the ink supply mechanism A2 on the downstream side falls to the ink collection plate 84 of the ink collection means 83 and gradually flows down on the ink collection plate 84 by its own weight. The ink is returned to the ink supply roll 52 at the ink transfer position b. Therefore, even when the plate cylinder 50 is disposed below the paper conveyance path, contamination by the ink 82 dripping from the gap d2 between the ink supply roll 52 and the doctor roll 53 can be prevented, and the ink 82 can be prevented. Eliminating work is also unnecessary.
[0060]
In the first embodiment, the ink collecting means 83 can pass the ink 82 in the vicinity of the ink receiving position a where the ink 82 falling from the gap d2 can be received and the outer peripheral surface of the ink supply roll 52. Since the ink recovery plate 84 is disposed so as to incline downward from the ink receiving position a toward the ink transfer position b over the ink transfer position b, the ink recovery plate 84 is used as the ink recovery means 83. Therefore, the configuration of the ink recovery means 83 is simple and the cost is low.
[0061]
Furthermore, in the first embodiment, the gap d1 between the location of the ink recovery plate 84 that becomes the ink transfer position b and the outer peripheral surface of the ink supply roll 52 is the gap between the ink supply roll 52 and the doctor roll 53. Since it is set to be larger than d2, the ink 82 can be delivered without adversely affecting the ink 82 having a constant film thickness adhered to the outer peripheral surface of the ink supply roll 52.
[0062]
Furthermore, in the first embodiment, since the ink delivery position a is a position above the lowest end position H1 of the ink supply roll 52, the ink 82 is delivered above the bottom end position H1 of the ink supply roll 52. Therefore, ink can be reliably delivered to the ink supply roll 52.
[0063]
FIG. 3 shows a second embodiment of the present invention, and is a configuration diagram of an ink supply mechanism A3 on the downstream side thereof. The second embodiment differs from the first embodiment only in the configuration of the ink recovery means 83 of the downstream ink supply mechanism A3, and the other configurations are the same as those in the first embodiment. Description is omitted.
[0064]
As shown in FIG. 3, the ink supply mechanism A <b> 3 has an ink receiving position a that can receive the ink 82 falling from the gap d <b> 2 (a position of a substantially vertical line V <b> 1 passing through the gap d <b> 2) and Both the ink transfer position b where the ink 82 can be passed in close proximity is defined as the outer peripheral surface 85a, and from the position of the outer peripheral surface 85a serving as the ink receiving position a toward the position of the outer peripheral surface 85a serving as the ink transfer position b. It is comprised by the ink collection | recovery roll 85 arrange | positioned so that it may become a downward inclined surface.
[0065]
Further, the gap d3 between the location of the ink collection roll 85 serving as the ink delivery position b and the outer peripheral surface of the ink supply roll 52 is set to be larger than the gap d2 between the ink supply roll 52 and the doctor roll 53. Yes.
[0066]
Further, the ink delivery position a is arranged so as to be located above the lowest end position H1 of the ink supply roll 52.
[0067]
The ink supply mechanism A3 of the second embodiment can obtain the same operations and effects as those of the first embodiment.
[0068]
In the second embodiment, the ink collecting means 83 is a roll-shaped ink collecting roll 85, and can be easily placed at a predetermined position by aligning the axis of the ink collecting roll 85, so that the installation work is easy. There is also an advantage of being.
[0069]
FIG. 4 shows a third embodiment of the present invention, and is a configuration diagram of an ink supply mechanism A4 on the downstream side thereof. The third embodiment differs from the second embodiment only in the configuration of the ink recovery means 83 of the downstream ink supply mechanism A4, and the other configurations are the same as those in the second embodiment. Description is omitted.
[0070]
As shown in FIG. 4, the ink supply mechanism A4 is configured such that the ink recovery means 83 is constituted by the ink recovery roll 86 as in the second embodiment, but the ink recovery roll 86 is rotated. ing. The rotation direction C is set to a direction in which the location of the outer peripheral surface 86a that becomes the ink receiving position a is upstream and the location of the outer peripheral surface 86a that becomes the ink transfer position b is downstream.
[0071]
The ink supply mechanism A4 of the third embodiment can obtain the same operations and effects as those of the second embodiment.
[0072]
In the third embodiment, the ink collecting means 83 is a roll-shaped ink collecting roll 86, and since the ink collecting roll 86 rotates, quick ink collection is possible.
[0073]
In addition, according to each said Example, although the case where it comprised so that the plate cylinders 40 and 50 might be pressed by the press rolls 46 and 56 sufficiently smaller diameter than the plate cylinders 40 and 50 was demonstrated, a press rotation member Any member may be used as long as it can apply a printing pressure between the plate cylinders 40 and 50. For example, the plate cylinders 40 and 50 may be configured by a pressure cylinder having substantially the same diameter. Further, according to each of the above embodiments, the ink film thickness regulating member is constituted by the cylindrical doctor rolls 43 and 53, but a predetermined gap can be formed between the ink supply rolls 42 and 52, and Any ink reservoir 81 may be used in the upper space formed between the ink supply rolls 42 and 53. Furthermore, according to each of the embodiments described above, the case where the paper transport path is in the horizontal direction and the plate cylinder is disposed at the lower position has been described. However, the paper transport path is other than the horizontal direction, for example, the vertical direction. The present invention can be applied to the case where the plate cylinder is arranged at the side position. In other words, the present invention can be applied to all ink supply mechanisms that are arranged in the plate cylinder and that may contaminate members in the plate cylinder due to ink dropping from the ink reservoir.
[0074]
【The invention's effect】
  As described above, according to the first aspect of the present invention, the ink that hangs down from the gap between the ink supply roll and the ink film thickness regulating member is returned to the ink supply roll by the ink recovery means. In the case where a plate cylinder is disposed below the ink cylinder, it is possible to prevent contamination due to ink dripping from the gap between the ink supply roll and the ink film thickness regulating member, and it is not necessary to remove ink. It becomes.In particular, since the ink collecting plate may be disposed at a predetermined position as the ink collecting means, the configuration of the ink collecting means is simple and the cost is low.
[0075]
  According to the invention of claim 2, the inkSince the gap between the location of the ink collection plate serving as the transfer position and the outer peripheral surface of the ink supply roll is set larger than the gap between the ink supply roll and the ink film thickness regulating member, the outer peripheral surface of the ink supply roll The ink can be delivered without adversely affecting the ink having a certain thickness attached to the ink.
[0076]
  According to the third aspect of the present invention, since the ink collecting roll may be disposed at a predetermined position as the ink collecting means, the configuration of the ink collecting means is simple and the cost is low. Further, the ink collecting means is a roll-shaped ink collecting roll, and can be easily placed at a predetermined position by aligning the axis of the ink collecting roll, so that installation work is easy.In particular, since the gap between the ink collection roll location serving as the ink delivery position and the outer peripheral surface of the ink supply roll is set larger than the gap between the ink supply roll and the ink film thickness regulating member, the ink supply roll Ink can be delivered without adversely affecting the ink having a fixed film thickness adhering to the outer peripheral surface.
[0077]
According to the invention of claim 4, since the ink collecting roll is rotated in the predetermined rotation direction, the ink can be collected quickly.
[Brief description of the drawings]
FIG. 1 shows an overall schematic configuration of a stencil printing apparatus according to a first embodiment of the present invention.
FIG. 2 is a configuration diagram of an ink supply mechanism disposed in a downstream plate cylinder according to the first embodiment of this invention.
FIG. 3 is a configuration diagram of an ink supply mechanism arranged in a downstream plate cylinder, showing a second embodiment of the present invention.
FIG. 4 is a configuration diagram of an ink supply mechanism arranged in a downstream plate cylinder, showing a third embodiment of the present invention.
FIG. 5 is an overall schematic configuration diagram of a conventional stencil printing apparatus.
FIG. 6 is a configuration diagram of an ink supply mechanism conceivable from a conventional example.
[Explanation of symbols]
1 Stencil printing machine (printing machine)
A2 to A4 ink supply mechanism
40, 50 plate cylinder
40a, 50a outer wall
42,52 Ink supply roll
43, 53 Doctor roll (Ink film thickness regulating member)
81 Ink reservoir
82 ink
83 Ink collection means
84 Ink collection plate
85,86 Ink collection roll
85a, 86a Outer peripheral surface
d2 Gap between ink supply roll and doctor roll
d1 Gap between the ink recovery plate at the ink transfer position and the ink supply roll
d3 Gap between the ink collecting roll and the ink supply roll at the ink transfer position

Claims (4)

An ink supply roll that is arranged inside the plate cylinder and rotates with the plate cylinder while being in contact with the inner peripheral surface of the plate cylinder and an outer peripheral surface of the ink supply roll are arranged in close proximity via a desired gap. An ink space regulating member, and an upper space formed by the outer peripheral surfaces of the ink film thickness regulating member and the ink supply roll adjacent to each other is defined as an ink reservoir, and is stored in the ink reservoir. Ink film that adheres to the outer peripheral surface of the ink supply roll by regulating the ink that adheres to the outer peripheral surface of the ink supply roll through the gap with the ink film thickness regulating member by rotation of the ink supply roll In an ink supply mechanism of a printing apparatus in which the thickness is continuously supplied to the inner peripheral surface of the plate cylinder,
Ink collecting means is provided for returning ink falling from the gap between the ink supply roll and the ink film thickness regulating member to the outer peripheral surface of the ink supply roll, and the ink collecting means removes ink falling from the gap. Ink collection arranged between the ink receiving position to be received and the ink passing position for transferring ink in the vicinity of the outer peripheral surface of the ink supply roll and inclined downward from the ink receiving position toward the ink passing position An ink supply mechanism for a printing apparatus, which is a plate . An ink supply mechanism for a printing apparatus according to claim 1,
The gap between the ink collecting plate portion serving as the ink delivery position and the outer peripheral surface of the ink supply roll is set to be larger than the gap between the ink supply roll and the ink film thickness regulating member. An ink supply mechanism for a printing apparatus. An ink supply roll that is arranged inside the plate cylinder and rotates with the plate cylinder while being in contact with the inner peripheral surface of the plate cylinder and an outer peripheral surface of the ink supply roll are arranged in close proximity via a desired gap. An ink space regulating member, and an upper space formed by the outer peripheral surfaces of the ink film thickness regulating member and the ink supply roll adjacent to each other is defined as an ink reservoir, and is stored in the ink reservoir. Ink film that adheres to the outer peripheral surface of the ink supply roll by regulating the ink that adheres to the outer peripheral surface of the ink supply roll through the gap with the ink film thickness regulating member by rotation of the ink supply roll the thickness Te ink supply mechanism smell of the plate cylinder the printing apparatus to the inner circumferential surface so as to continuously supply as constant,
Ink collecting means is provided for returning ink falling from the gap between the ink supply roll and the ink film thickness regulating member to the outer peripheral surface of the ink supply roll, and the ink collecting means removes ink falling from the gap. Both the ink receiving position that receives the ink and the ink passing position that delivers ink in the vicinity of the outer peripheral surface of the ink supply roll are both outer peripheral surfaces, and the outer peripheral surface that is the ink passing position from the location of the outer peripheral surface that is the ink receiving position towards the point Ri Oh in place ink recovery roll such that the lower inclined surface, the gap between the outer peripheral surface of the portion of the ink recovery roll of the ink passing position said ink supply roll, said the ink supply device of the printing apparatus being characterized in that is set larger than the gap between the ink film thickness regulating member and the ink supply roll . An ink supply mechanism for a printing apparatus according to claim 3,
The printing apparatus according to claim 1, wherein the ink collecting roll is rotated in a rotational direction in which an outer peripheral surface portion serving as the ink receiving position is upstream and an outer peripheral surface portion serving as the ink delivery position is downstream. Ink supply mechanism.

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