JP2004017440A - Stencil printing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stencil printing device which simplifies the constitution of a device body and changes the timing of setting a press roller in a contact position/setting it free from the position. <P>SOLUTION: A printing drum unit 40 supporting a plate cylinder 20 in a freely rotating manner includes a cam which rotates synchronously with the rotation of the plate cylinder 20. The cam 45 controls the timing of bringing the press roller mounted on the device body ll into contact with the plate cylinder 20 and setting the press roller free from the contact position. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a stencil printing apparatus, and more particularly to a stencil printing apparatus to which a printing drum unit can be attached and detached.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in a stencil printing machine, a stencil sheet is attached to a plate cylinder so as to cover an opening provided in the plate cylinder. Therefore, even if the printing paper size is small, a base paper of a fixed length is always required.
[0003]
In order to eliminate such waste of the base paper, it is only necessary to use a plate cylinder in which the size of the opening differs depending on the size of the printing paper. In this case, there is no need for the press roller to press the plate cylinder, which has neither base paper nor printing paper, and if pressurized, the press roller surface will be stained with ink, so the press roller presses the printing paper against the plate cylinder. It is necessary to change the timing of contact with and separation from the plate cylinder in accordance with the printing paper size, that is, the size of the aperture of the plate cylinder.
[0004]
For example, Japanese Unexamined Patent Publication No. 1-18683 discloses that a printing drum unit having a different size of an opening portion of a plate cylinder can be attached to and detached from an apparatus main body. A plurality of cam plates of different shapes are provided according to the size of the opened hole, and the cam plate is selected by moving the cam plate in the axial direction according to the installed printing drum unit, and the timing at which the press roller contacts and separates It is proposed to change the value according to the printing paper size.
[0005]
[Problems to be solved by the invention]
However, if a mechanism for moving the cam plate in the axial direction to change the contact / separation timing of the press roller is provided in the apparatus main body, the configuration of the apparatus main body becomes complicated. Further, it is necessary to provide a number of cam plates in the apparatus main body in advance corresponding to the types of the opening size, and the cam mechanism is complicated and large in size to cope with many types of paper sizes.
[0006]
Therefore, a technical problem to be solved by the present invention is to provide a stencil printing apparatus capable of changing the contact / separation timing of the press roller, which can simplify the configuration of the apparatus main body.
[0007]
[Means for Solving the Problems]
The present invention provides a stencil printing apparatus having the following configuration to solve the above technical problem.
[0008]
The stencil printing apparatus is of a type in which a printing drum unit that rotatably supports a plate cylinder can be attached to and detached from the apparatus body. The printing drum unit includes a cam that rotates in synchronization with rotation of the plate cylinder. The cam controls the timing at which the press roller provided on the apparatus main body comes into contact with and separates from the plate cylinder.
[0009]
In the above configuration, each print drum unit is provided with a cam corresponding to the size of the aperture of the plate cylinder, so that the timing at which the press roller comes into contact with or separates from the plate cylinder is determined by the printing paper size, that is, It can be controlled according to the size of the part.
[0010]
According to the above configuration, since the configuration that changes in accordance with the print paper size is provided in the print drum unit, the configuration on the apparatus main body side can be simplified. Further, the configuration of the printing drum unit is simple because it is not necessary to move the cam in the axial direction.
[0011]
Therefore, the configuration of the apparatus main body of the stencil printing apparatus capable of changing the contact / separation timing of the press roller can be simplified.
[0012]
Further, the present invention provides a stencil printing apparatus having the following configuration in order to solve the above technical problems.
[0013]
The stencil printing apparatus is of a type in which a printing drum unit that rotatably supports a plate cylinder can be attached to and detached from the apparatus body. The plate drum unit includes a first cam that rotates in synchronization with rotation of the plate cylinder. The apparatus main body includes a second cam that rotates in synchronization with the rotation of the plate cylinder. The first cam controls the timing at which the press roller begins to separate from the plate cylinder. The second cam controls the timing when the press roller starts to approach the plate cylinder.
[0014]
In the above configuration, the second cam provided on the apparatus main body corresponds to the size of the aperture of the plate cylinder having the maximum printing paper size, and the first cam provided on the printing drum unit is provided for each printing drum unit. The cam is set in accordance with the size of the opening of the cylinder, and the timing at which the print drum starts to separate from the plate cylinder in accordance with the corresponding printing paper size of the printing drum is controlled. The state of the press roller separated from the plate cylinder by the first cam is taken over by the second cam, and the timing at which the press roller starts to approach the plate cylinder is controlled by the second cam.
[0015]
According to the above configuration, since the configuration that changes in accordance with the print paper size is provided on the print drum unit side, the configuration of the apparatus main body can be simplified. Further, the configuration of the printing drum unit is simple because it is not necessary to move the cam in the axial direction.
[0016]
Therefore, the configuration of the apparatus main body of the stencil printing apparatus capable of changing the contact / separation timing of the press roller can be simplified.
[0017]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described below with reference to FIGS.
[0018]
First, a first embodiment of the present invention will be described with reference to FIGS.
[0019]
FIG. 1 is a diagram illustrating the configuration of the stencil printing apparatus 10. In the stencil printing apparatus 10, an image reading device 18 for reading a document for stencil making is arranged on an upper part of the apparatus main body 11.
[0020]
In the apparatus main body 11, the sheets 2 stored in a state of being stacked on the sheet feeding unit 12 are separated one by one by a separating plate 31 and a sheet feeding roller 30, conveyed, and pressed on the plate cylinder 20 by a press roller 22 in the middle. After being printed and printed, it is conveyed to the paper tray 14.
[0021]
In front of the plate cylinder 20, a sheet detection sensor 36 for detecting the passage of the sheet and feed rollers 32 and 33 for sending the sheet 2 to the plate cylinder 20 at a predetermined timing in synchronization with the rotation of the plate cylinder 20 are arranged. Have been.
[0022]
A master obtained by cutting the master roll 4 made by the thermal head 24 into a predetermined length based on an image read by the image reading device 18 is attached to the plate cylinder 20. The master affixed to the plate cylinder 20 is removed by the paper discharge unit 26 and collected. An ink roller 23 is arranged in the plate cylinder 20 so that a predetermined amount of ink is applied to the inner peripheral surface of the plate cylinder 20. The plate cylinder 20 is provided with an opening 20a (see FIG. 4) in which a large number of through-holes are formed, so that ink can pass therethrough. The master is attached so as to cover the opening 20a.
[0023]
Between the plate cylinder 20 and the paper receiving tray 14, a sheet attached to the plate cylinder 20 (specifically, a master attached to the plate cylinder 20) is caught on the sheet, and a paper peeling claw 28 for peeling off the sheet and a paper peeling claw are provided. An air blower 29 is provided to send air between the sheet 28 and the sheet and to easily separate the sheet from the plate cylinder 20.
[0024]
Further, a paper discharge mechanism for transporting the printed paper is provided. That is, the paper discharge belt 34 that circulates so that the upper part moves along the paper transport path F is disposed. A large number of through holes are formed in the discharge belt 34, and a fan unit 35 that sucks air is disposed below an upper portion of the discharge belt 34. The fan unit 35 sucks the upper printed paper onto the discharge belt 34 through the through hole of the discharge belt 34. The sucked sheet is conveyed to the sheet receiving table 14 by rotation of the sheet ejection belt 34.
[0025]
Between the plate cylinder 20 and the paper discharge belt 34, a jam detection sensor 38 for monitoring whether jamming such as jamming of the paper after printing has occurred is arranged.
[0026]
The printing drum unit 40 that rotatably supports the plate cylinder 20 is configured substantially in the same manner as the general printing drum unit shown in the perspective view of FIG. As the printing drum unit 40, one having a different size and shape of the opening 20a (see FIG. 4) of the plate cylinder 20 according to the printing paper size is used.
[0027]
The printing drum unit 40 rotatably supports the plate cylinder 20 between the first vertical plate 42 and the second vertical plate 44. The first vertical plate 42 and the second vertical plate 44 are connected by a pair of rails 46 and 47 and a stay 48. The apparatus main body 11 is provided with guide portions (not shown) for guiding the rails 46 and 47, and can be mounted on the apparatus main body 11 by inserting the printing drum unit 40 in the axial direction from the front side of the apparatus main body 11. It has become. At this time, the printing drum unit 40 is inserted into the apparatus main body 11 from the first vertical plate 42 side.
[0028]
As shown in the sectional views of the main part of the press roller drive mechanism in the stencil printing apparatus of the first embodiment of FIGS. 2 and 3, the plate cylinder 20 is fixed to the printing drum shaft 21 and is integrated with the printing drum shaft 21. It is designed to rotate. The print drum shaft 21 is rotatably supported by a first vertical plate 42 and a second vertical plate 44 (not shown in FIG. 3) of the print drum unit 40. One of the printing drum shafts 21 penetrates the first vertical plate 42, and a driving plate 43 is fixed to the shaft end 21a. The drive plate 43 is provided with a drive lever engagement hole 43a.
[0029]
In the apparatus main body 11, a driving flange 50 is disposed at an end of a space into which the printing drum unit 40 is inserted. The drive flange 50 is fixed to the drive shaft 51 and is driven to rotate. The drive flange 50 is provided with a drive lever 52 that protrudes in the axial direction from the side surface toward the print drum unit 40, and drives the drive plate 43 of the print drum unit 40 when the print drum unit 40 is inserted into the apparatus main body 11. It is designed to be inserted into the lever engagement hole 43a. Thereby, the rotation of the drive flange 50 on the apparatus main body 11 side is transmitted to the plate cylinder 20, and the plate cylinder 20 can be rotationally driven from the apparatus main body 11 side.
[0030]
As shown in FIG. 3, a cam plate 45 is fixed to the printing drum shaft 21 between the first vertical plate 42 and the driving plate 43. The cam plate 45 is adapted to engage with a cam follower 64 of a swing arm 60 provided on the apparatus main body 11. The swing arm 60 is fixed to a support shaft 62 rotatably supported by the apparatus main body 11.
[0031]
As shown in the perspective view of FIG. 4, the support shaft 62 extends along the plate cylinder 20. A pair of support arms 66 and 67 are fixed to the support shaft 62. The press roller 22 is rotatably supported by the ends of the pair of support arms 66 and 67.
[0032]
As shown in the end views of FIGS. 4, 5, and 6, a spring 63 is locked to the swing arm 60. The swing arm 60 is biased by a biasing force of a spring 63 in a direction in which the press roller 22 approaches the plate cylinder 20 (clockwise in FIGS. 5 and 6).
[0033]
The rocking arm 60 is provided with a pinch lever locking portion 61 for locking the pinch lever 70. When the pinch lever 70 is locked, the rocking arm 60 rocks by the bias of the spring 63. Is to be blocked. When the print drum unit 40 is attached to and detached from the apparatus main body 11, the pinch lever 70 is locked by the pinch lever locking portion 61, and holds the cam follower 64 in a state of being retracted radially outward with respect to the cam plate 45. The plate 43 does not interfere with the swing arm 60 and the cam follower 64.
[0034]
Next, the operation will be described with reference to FIGS.
[0035]
As shown in FIG. 5, when the cam follower 64 abuts on the protrusion 45 a of the cam plate 45, the swing arm 60 counters the urging force of the spring 63, centering on the support shaft 62 in the counterclockwise direction in the figure. Rocks. As a result, the press roller 22 also swings counterclockwise and separates from the plate cylinder 20.
[0036]
On the other hand, as shown in FIG. 6, when the cam follower 64 is not in contact with the protrusion 45 a of the cam plate 45, the swing arm 60 swings clockwise in the figure by the urging force of the spring 63. Thus, the press roller 22 also swings clockwise and approaches the plate cylinder 20.
[0037]
By appropriately configuring the protruding portion 45a of the cam plate 45, the timing at which the press roller 22 comes into contact with or separates from the plate cylinder 20 can be set. For example, when the circumferential dimension of the opening portion 20a of the plate cylinder 20 is small, the circumferential size of the projecting portion 45a of the cam plate 45 is increased. The circumferential dimension of the protrusion 45a of the plate 45 is reduced.
[0038]
Since the press roller 22 comes into contact with and separates from the plate cylinder 20 at different timings for each print drum unit 40, a master having a length corresponding to the print paper size can be used.
[0039]
As described above, the configuration of the apparatus main body of the stencil printing apparatus capable of changing the contact / separation timing of the press roller can be simplified.
[0040]
Next, a stencil printing apparatus according to a second embodiment of the present invention will be described with reference to FIGS.
[0041]
The stencil printing apparatus according to the second embodiment has a configuration substantially similar to that of the stencil printing apparatus according to the first embodiment. Hereinafter, differences will be mainly described, and the same reference numerals are used for similar components.
[0042]
As shown in FIG. 7, a second cam plate 54 is fixed to the drive shaft 51 of the apparatus main body 11 separately from the first cam plate 45 x of the printing drum unit 41. The swing arm unit 70 includes a first arm 72 and a second arm 74 fixed to the support shaft 62. The first arm 72 and the second arm 74 are connected by a connecting member 70a, and swing around the support shaft 62. The first arm 72 is provided with a cam follower 73 that engages with the first cam plate 45x. The second arm 74 is provided with a cam follower 75 that engages with the second cam plate 54.
[0043]
As shown in FIG. 8, the swing arm unit 70 is provided with a press roller 22 similarly to the swing arm 60 of the first embodiment, and a direction in which the press roller 22 is pressed against the plate cylinder 20 by a spring 63. It is urged to. Further, the swing arm unit 70 is provided with a locking portion 71 for locking the pinch lever 61.
[0044]
In FIG. 8, the plate cylinder 20 rotates clockwise. When the cam follower 73 of the first arm 72 comes into sliding contact with the radially projecting portion of the first cam plate 45x, the swing arm unit 70 swings around the support shaft 62 in the counterclockwise direction in FIG. Leaves the plate cylinder 20. At this time, the cam follower 75 of the second arm 74 is not yet in sliding contact with the radially projecting portion of the second cam plate 54.
[0045]
Before the plate cylinder 20 rotates and the cam follower 73 of the first arm 72 is released from sliding contact with the radially projecting portion of the first cam plate 45x, the cam follower 75 of the second arm 74 is moved to the second cam plate. Since the oscillating arm unit 70 slidably contacts the portion protruding in the radial direction of 54, the oscillating arm unit 70 remains oscillating in the counterclockwise direction, and the press roller 22 continues to be away from the plate cylinder 20.
[0046]
When the plate cylinder 20 further rotates and the portion of the second cam plate 54 projecting in the radial direction passes through the cam follower 75 of the second arm 74, the swing arm 70 swings clockwise in FIG. Then, the press roller 22 is pressed against the plate cylinder 20.
[0047]
That is, the press end timing at which the press roller 22 separates from the plate cylinder 20 is determined by the first cam plate 45x. The second cam plate 54 determines the press start timing at which the press roller 22 starts to contact the plate cylinder 20.
[0048]
A second cam plate 54 is provided on the apparatus main body 11 to fix the timing at which the press roller 22 contacts and separates from the plate cylinder 20 with respect to the aperture size of the plate cylinder corresponding to the maximum print paper size. By providing only one cam plate 45x to change only the timing at which the press roller starts to separate from the plate cylinder in accordance with the size of the printing paper, there is no need to make changes to the second cam plate 54 of the apparatus body 11, and it is provided separately. It is not necessary to control the timing at which the press roller 22 comes into contact with or separates from the plate cylinder using the cam plate. Therefore, the configuration can be simplified.
[0049]
As described above, the configuration of the apparatus main body of the stencil printing apparatus capable of changing the contact / separation timing of the press roller can be simplified.
[0050]
It should be noted that the present invention is not limited to the above-described embodiment, but can be implemented in other various modes.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a configuration of a stencil printing apparatus. FIG. 2 is a perspective view of a general printing drum unit of the stencil printing apparatus. FIG. 3 is a diagram showing a first embodiment of the present invention. FIG. 4 is a perspective view of a press roller driving mechanism of the stencil printing machine. FIG. 5 is an end view of an AA line in FIG. 4. FIG. 6 is an end view of an AA line in FIG. FIG. 8 is a sectional view of a main part of a press roller driving mechanism of a stencil printing machine according to a second embodiment of the invention. FIG. 8 is an end view taken along the line BB of FIG.
Reference Signs List 10 stencil printing apparatus 11 apparatus main body 20 plate cylinder 22 press rollers 40, 41 printing drum unit 45 cam plate (cam)
45x 1st cam plate (1st cam)
54 2nd cam plate (2nd cam)

Claims (2)

In a stencil printing machine in which a printing drum unit rotatably supporting a printing drum can be attached to and detached from an apparatus main body,
The printing drum unit includes a cam that rotates in synchronization with the rotation of the plate cylinder, and the cam controls a timing at which a press roller provided on the apparatus main body approaches and separates from the plate cylinder. , Stencil printing equipment. In a stencil printing machine in which a printing drum unit rotatably supporting a printing drum can be attached to and detached from an apparatus main body,
The plate cylinder drum unit includes a first cam that rotates in synchronization with rotation of the plate cylinder,
The apparatus body includes a second cam that rotates in synchronization with the rotation of the plate cylinder,
The first cam controls a timing at which the press roller starts to separate from the plate cylinder,
The stencil printing apparatus, wherein the second cam controls a timing at which the press roller starts to approach the plate cylinder.

Images