JP4064500B2 - Rotary stencil printing machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rotary stencil printing machine and a peripheral speed control method for a discharge belt of the rotary stencil printing machine.
[0002]
[Prior art]
Conventionally, in the rotary stencil printing press 1 shown in the schematic front view of FIG. 1, a sheet that passes between the plate cylinder 20 and the press roller 22 and is printed on the upper surface of the sheet is attracted to the discharge belt 30. It is conveyed and discharged to the paper receiving tray 40. In the rotary stencil printing machine 1, the discharged paper hits the guide plate 42 of the paper receiving tray 40 and is stacked on the paper receiving tray 40 with the front ends of the paper aligned. In general, the peripheral speed of the paper discharge belt 30 is set slightly faster than the peripheral speed of the plate cylinder 20. The paper discharge belt 30 is driven by the same drive source as the plate cylinder 20 and is accelerated at a constant rate with respect to the peripheral speed of the plate cylinder 20 or when it is driven at a constant peripheral speed by a dedicated drive source. There is.
[0003]
By the way, immediately after the start of printing, since the ink is not sufficiently familiar with the stencil sheet mounted on the plate cylinder 20, it is necessary to rotate the plate cylinder 20 very slowly so that printing blur does not occur. . At this time, when the speed is increased at a constant rate with respect to the peripheral speed of the plate cylinder 20, the peripheral speed of the paper discharge belt 30 becomes too slow, and the printed paper is vigorous from the paper discharge belt 30. Since it is not discharged, it does not hit the guide plate 42 of the paper receiving tray 40. For this reason, the overlapping of the printed sheets on the sheet receiving tray 40 becomes uneven.
[0004]
On the other hand, when the discharge belt 30 is driven at a constant peripheral speed, the peripheral speed of the discharge belt 30 is set slightly higher than the maximum peripheral speed of the plate cylinder 20 and is always faster than the peripheral speed of the plate cylinder 20. It is necessary to be. In this case, the printed paper on the paper receiving tray 40 is not uneven, but noise during printing always increases. In addition, in the case of soft paper, inconveniences such as bending when hitting the guide plate 42 of the paper receiving tray 40 occur.
[0005]
[Problems to be solved by the invention]
Therefore, the technical problem to be solved by the present invention is to control the peripheral speed of the paper discharge belt of the rotary stencil printing press and the rotary stencil printing press which appropriately control the peripheral speed of the paper discharge belt corresponding to the peripheral speed of the plate cylinder. Is to provide a method.
[0006]
[Means for solving the problems and actions / effects]
In order to solve the above technical problem, the present invention provides the following peripheral speed control method for a discharge belt of a rotary stencil printing press.
[0007]
The rotary stencil printing machine is of a type in which a sheet printed by passing between a plate cylinder and a press roller is sucked and discharged by a discharge belt. In this rotary stencil printing press, when the peripheral speed of the plate cylinder is slower than or equal to a predetermined reference peripheral speed, it is not less than the reference peripheral speed and is substantially equal (preferably a peripheral speed slightly higher than the reference peripheral speed). Then, the paper discharge belt is driven. On the other hand, when the peripheral speed of the plate cylinder is faster than the reference peripheral speed, the plate peripheral speed approximately like properly and lower than without the peripheral speed of the cylinder (preferably, slightly faster peripheral speed than the plate cylinder peripheral speed) the exhaust in Drive the paper belt.
[0008]
According to the above method, the paper discharge belt is not driven at a peripheral speed lower than a peripheral speed that is substantially equal to the reference peripheral speed, so that it is possible to prevent the printed paper from being uneven. In addition, since the discharge belt is increased according to the peripheral speed of the plate cylinder only when the peripheral speed of the plate cylinder is higher than the reference peripheral speed, the noise generated by the discharge belt when the plate cylinder is driven at a low speed. Becomes smaller.
[0009]
Accordingly, the peripheral speed of the paper discharge belt can be appropriately controlled in accordance with the peripheral speed of the plate cylinder.
[0010]
The present invention provides various forms of a rotary stencil printing press capable of implementing the above method.
[0013]
The rotary stencil printing press of the present invention includes a first drive means, a second drive means, and a drive selection means. The first driving means can drive the paper discharge belt at a constant peripheral speed lower than the maximum peripheral speed of the plate cylinder. The second driving means can drive the paper discharge belt at a speed increased at a constant rate with respect to the peripheral speed of the plate cylinder. The drive selection means selects the first or second drive means for driving the paper discharge belt (30) at a faster peripheral speed when driving the paper discharge belt.
[0014]
According to the above configuration, when the peripheral speed of the plate cylinder is slower than or equal to the reference peripheral speed, the paper discharge belt is driven at a peripheral speed substantially equal to the reference peripheral speed by the first driving means, and the peripheral speed of the plate cylinder is increased. When it is faster than the reference peripheral speed, it is driven at a peripheral speed approximately equal to the peripheral speed of the plate cylinder by the second driving means. According to the above configuration, the paper discharge belt can be driven according to the peripheral speed of the plate cylinder only by the mechanical configuration.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the rotary stencil printing machine 1 according to an embodiment of the present invention shown in FIGS. 1 to 3 will be described in detail.
[0016]
As shown in FIG. 1, the rotary stencil printing machine 1 includes a paper feed tray 10 for placing paper 18 for printing on both sides of a plate cylinder 20, and a paper tray 40 for collecting printed paper. Have
[0017]
The paper feed table 10 is provided with a paper feed ring 12 and a separating plate 13 at an end portion on the plate cylinder 20 side, and feeds sheets 18 from the paper feed table 10 one by one to the plate cylinder 20 side. A pair of timing rollers 14 is provided between the sheet feed table 10 and the plate cylinder 20. The sheet sent from the sheet feeding table 10 comes into contact with the tangent of the timing roller 14, and the timing roller 14 rotates at a predetermined timing corresponding to the rotation of the plate cylinder 20, so that the plate cylinder 20 does not tilt. And the press roller 22. A paper passage sensor 17 (see FIG. 2) that detects the passage of the paper is provided immediately before the timing roller 14.
[0018]
The stencil sheet made by the plate making unit 21 is automatically mounted on the outer peripheral surface of the plate cylinder 20. Further, the stencil sheet is automatically removed from the plate cylinder 20 and collected by the stencil collecting unit 29. A press roller 22 that moves up and down appropriately is disposed below the plate cylinder 20. An ink roller 24 in contact with the inner peripheral surface of the plate cylinder 20 is disposed inside the plate cylinder 20 so that ink supplied by an ink motor 25 (see FIG. 2) is applied to the inner peripheral surface of the plate cylinder 20. It has become. The press roller 22 rises when the paper sent from the timing roller 14 passes between the plate cylinder 20 and the press roller 22, and presses the paper against the stencil sheet of the plate cylinder 20. As a result, printing is performed on the paper.
[0019]
A paper discharge belt 30 is provided between the plate cylinder 20 and the paper tray 40. The paper discharge belt 30 sucks printed paper onto the belt surface by suction of a paper discharge fan 32 (see FIG. 2). In order to promote the adsorption of the paper onto the paper discharge belt 30, air is supplied above the paper discharge belt 30 from a top blow fan 34 (see FIG. 2).
[0020]
The paper tray 40 is provided with a guide plate 42 that is orthogonal to the paper transport direction 46, and the paper discharged from the paper discharge belt 30 hits the guide plate 42 and is aligned on the paper tray 40. It is supposed to overlap. The paper receiving tray 40 is also provided with a pair of guide plates 44 that extend in the paper transport direction 46 and align both sides of the paper.
[0021]
As shown in the block diagram of FIG. 2, the printing machine 1 includes a CPU 2 that controls the operation of the printing machine 1, a ROM 4, a RAM 5, a power supply 6, a main motor 26, a paper discharge belt motor 36, Paper feed solenoid 16, ink motor 25, paper discharge fan 32, top blow fan 34, main motor encoder 27 for speed control of main motor 26, and discharge for speed control of paper discharge belt motor 36 The paper belt motor encoder 37, the paper passage sensor 17, and the printing speed setting means 8 are connected.
[0022]
The main motor 26 drives the paper feed ring 12, the timing roller 14, and the plate cylinder 20. The feed solenoid 16 disengages a clutch (not shown) and transmits or interrupts the rotation from the main motor 26 to the feed ring 12 and the timing roller 14. The paper discharge belt motor 36 drives the paper discharge belt 30 independently. Specifically, the printing speed setting means 8 is, for example, an operation panel (not shown) of the printing machine 1 and transmits the setting value of the printing speed to the CPU 2.
[0023]
As shown in the graph of FIG. 3, the CPU 2 sets the peripheral speeds of the plate cylinder 20 and the paper discharge belt 30 in accordance with the set speed set by the printing speed setting unit 8. That is, the set speed is set by the printing speed setting means 8 in six stages from ultra-low speed to fifth speed (maximum speed). For the plate cylinder 20, the CPU 2 sets the peripheral speeds 29a to 29f corresponding to the set speed. On the other hand, for the paper discharge belt 30, the CPU 2 sets a peripheral speed 39a that is slightly faster than the peripheral speed 29d of the plate cylinder 20 corresponding to the third speed when the set speed is from an ultra-low speed to a third speed. Further, at the fourth speed and the fifth speed, peripheral speeds 39e and 39f that are slightly higher than the peripheral speeds 29e and 29f of the plate cylinder 20 corresponding to the respective set speeds are set.
[0024]
In this way, by setting the peripheral speed of the paper discharge belt 30 based on the third speed, which is a medium printing speed, the discharge speed can be reduced even at an ultra low speed to a third speed that is slower than or equal to the medium printing speed. Since the peripheral speed of the paper belt 30 is medium 39a, the printed paper is discharged from the paper discharge belt 30 at a medium speed, and hits the guide plate 42 of the paper tray 40 and is aligned on the paper tray 40. Overlaid with. The peripheral speed of the paper discharge belt 30 is relatively high speeds 39e and 39f only when the printing speed is higher than the fourth speed and the fifth speed, and is relatively low speed 39a at other times. Noise at times other than high-speed printing can be reduced. Specifically, the above-described medium printing speed, that is, the third speed, is 20 to 80 sheets per minute, preferably 30 to 60 sheets per minute. The peripheral speed 39a of the paper discharge belt 30 when the printing speed is slower than or equal to this medium printing speed is 17 to 34 m / min.
[0025]
Therefore, the peripheral speed of the paper discharge belt 30 can be appropriately controlled according to the peripheral speed of the plate cylinder 20.
[0026]
In addition, this invention is not limited to the said embodiment, It can implement in another various aspect. For example, the discharge belt motor 36 is driven at a constant speed to constitute a first drive means, and the discharge belt 30 is driven at a peripheral speed increased by a constant rate with respect to the peripheral speed of the plate cylinder 20 by the main motor 26. Another second driving means for driving is provided, and the driving force from each driving means is transmitted to the paper discharge belt 30 via the one-way clutch (drive selection means), and the paper discharge belt 30 is driven faster. The paper discharge belt 30 may be driven by driving means.
[Brief description of the drawings]
FIG. 1 is a schematic front view of a conventional example and a rotary stencil printing press according to an embodiment of the present invention.
FIG. 2 is a block diagram of a rotary stencil printing press according to an embodiment of the present invention.
FIG. 3 is a graph of the peripheral speed of the rotary stencil printing machine according to the embodiment of the present invention.
[Explanation of symbols]
1 Rotational stencil printing machine 2 CPU (comparison means, peripheral speed setting means)
4 ROM
5 RAM
6 Power supply 8 Printing speed setting means (plate cylinder peripheral speed detection means)
DESCRIPTION OF SYMBOLS 10 Paper feed stand 12 Paper feed ring 13 Separator plate 14 Timing roller 16 Paper feed solenoid 17 Paper passage sensor 18 Paper 20 Plate cylinder 21 Plate making part 22 Press roller 24 Ink roller 25 Ink motor 26 Main motor 27 Main motor encoder 28 Base paper collection part 29a to 29f Peripheral speed 30 Paper discharge belt 32 Paper discharge fan 34 Top blow fan 36 Paper discharge belt motor (paper discharge belt drive means)
37 Paper discharge belt motor encoder 39a, 39e, 39f Peripheral speed 40 Paper cradle 42, 44 Guide plate 46 Paper transport direction

Claims (1)

  In the rotary stencil printing machine (1) for transporting and discharging the paper printed between the plate cylinder (20) and the press roller (22) while being adsorbed by the paper discharge belt (30), the above plate A first driving means capable of driving the paper discharge belt (30) at a constant peripheral speed (39a) lower than a maximum peripheral speed (29f) of the cylinder (20), and a peripheral speed of the plate cylinder (20); Second driving means capable of driving the paper discharge belt (30) at a peripheral speed (39e, 39f) increased at a constant rate with respect to (29e, 29f), and driving the paper discharge belt (30) A rotary stencil printing machine comprising: a drive selection unit that selects the first or second drive unit that drives the paper discharge belt (30) at a faster peripheral speed.

Images