JPH024427B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a register adjustment device that can be applied to various sheet-fed printing presses and rotary printing presses.

In a printing machine, if the designs of the first color, second color, . Therefore, in order to achieve the above object, register adjustment has been conventionally performed. The conventional method is to place a "〓" mark on the plates for the first, second, and nth colors, automatically detect this mark before printing, and calculate the phase difference between that signal and a predetermined reference sensor signal. were automatically adjusted to match perfectly.

However, according to this conventional method, the reference sensor requires a high-precision output and is not only very expensive, but also has the disadvantage that positioning the reference sensor requires labor.

The present invention was proposed in order to eliminate the above-mentioned conventional drawbacks, and detects the amount of twist of the plate from the phase difference between the horizontal register mark on the operating side and the horizontal register mark on the driving side. By detecting the amount of misregistration error in the left and right directions from the phase difference between the drive side diagonal register marks and adjusting the register by moving the plate cylinder according to the detection signal, a reference sensor is not required and the result can be obtained at a low price. In addition, it is an object of the present invention to provide a register adjustment device that eliminates the need for positioning a reference sensor and that enables automatic register adjustment of left-right direction torsion without a reference sensor.

Embodiments of the present invention will be described below with reference to the drawings. First, FIG. 1 shows a schematic structure of a sheet-fed printing press. The sheet-fed printing machine shown in FIG. 1 is composed of a paper feeding device 1, printing devices 2 and 3, and a paper discharging device 4. By the way, this paper feeding device 1 is a device that stores printing paper 5 and feeds the printing paper 5 to printing devices 2 and 3.
Further, in the printing device 2, the ink 8 stored in the ink tray 6 reaches the plate attached to the plate cylinder 12 via the ink roller 10.

Further, the ink 8 attached to the plate is transferred to the blanket cylinder 14, and the printing paper 5 flowing from the paper feeder 1 is printed between the blanket cylinder 14 and the impression cylinder 16. This is the first color printing. The printing paper 5 that has passed through the first color printing device 2 enters the second color printing device 3 via an intermediate cylinder 17, and the ink tray 7, ink 9, ink roller group 11, and plate cylinder 13 function similarly to the first color printing device 2. The ink 9 is then transferred to the blanket cylinder 15, and the printing paper 5 is printed by the blanket cylinder 15 and the impression cylinder 18, resulting in second color printing. The printed paper 5 printed in both one color and two colors as described above is sent to the paper ejection device 4 via the paper ejection cylinder 19,
All operations are complete.

Next, the structure of the apparatus will be explained. FIG. 2 is a perspective view of the cylinder of the sheet-fed printing press shown in FIG. 1. In FIG. 2, the plate 28 is placed on the plate cylinder 12.
The plate 28 has register marks 24 and 25 on the operation side and register marks 26 and 27 on the drive side.

The register marks 24 and 26 are parallel to the front edge of the plate 28, and the register marks 25 and 2
7 attaches a mark having an inclination angle of θ degrees with respect to the register marks 24 and 26. Emitter 20, receiver 2
1 is fixed at a position where the register marks 24 and 25 can be detected. Further, the light emitter 22 and the light receiver 23 are fixed at positions where the register marks 26 and 27 can be detected.

The proximity switch disc 36 is directly connected to the plate cylinder 12, and the proximity switch 37 is connected to the proximity switch disc 3.
Fix it in a position opposite to 6. Further, the pulse signal generator 34 is directly connected to the impression cylinder 16 through a shaft 35. The register correction motors 30 and 31 are directly connected to a plate cylinder driving device 32 and connected to the plate cylinder 12 by a shaft 33. The plate cylinder driving device 32 has a known mechanical mechanism for adjusting the torsion and left and right register, and is movable only when the above-mentioned adjustment is necessary. Further, the plate cylinder 13 of the second color printing device is also provided with a register mark, a light emitter, a light receiver 2, a proximity switch, and a proximity switch disc, as in the case of the first color. Note that the proximity switch disc 3
6. The proximity switch 37 may be installed anywhere as long as it is in the same phase as the rotation of the sheet-fed printing press.

Next, to explain the register mark, the third
As shown in the figure, the operating side register marks 24, 2
5 and drive side register marks 26 and 27 are plate 2.
8 at the same distance from the center in the left-right direction Q and at symmetrical positions. In FIG. 3, X ₁ -Y ₁ represents the operating side light emitter/receiver detection line, and X ₂ -Y ₂ represents the drive side light emitter/receiver detection line.

Next, to explain the amount of twist and the registration error in the left-right direction Q, the plate cylinder 1 is
If the register marks 24 and 26 are attached at the center in the horizontal direction, the positions of the register marks 24 and 26 in the vertical direction P will be the same. But if the plate is installed twisted,
By detecting the positions of the register marks 24 and 26 as shown in FIG. 4, the error in the vertical direction P can be reduced to ε ₉
It is expressed as This is the amount of twist.

Furthermore, if the plate 28 is installed offset from the center in the horizontal direction, the error in the horizontal direction Q is expressed as ε ₁₀ by detecting the positions of the register marks 25 and 27 as shown in FIG. If the register correction motor is operated so as to reduce the twist amount ε ₉ and the horizontal error ε ₁₀ to zero, the plate 28 will be at the center position in the left and right directions without twisting.

Next, the operation of detecting these register errors using a specific circuit will be explained based on FIGS. 6 and 7. Emitters 20, 22, receiver 2
1 and 23 move the proximity switch disc 36 to a phase where the first color register marks 24 to 27 can be detected, and the proximity switch 37 is set to generate a signal at that time.

Now, in the above setting state, assuming that an error of ε ₉ occurs in the twist amount of the first color on the printing plate, and ε ₁₀ in the left-right direction registration error, the proximity switch 37 is activated by the proximity switch disc 36 as follows. When the light projectors 20, 22 and the light receivers 21, 23 pass over the register marks, they turn on. This corresponds to timing 49 in FIG.

On the other hand, by rotating the plate cylinder 12, the projector 2
0, 22, and the light receivers 21 and 23 are detecting the printing plate, but when the gates 48 and 50 are opened at the timing 49, the light emitters 20 and 22 and the light receiver 2 are detected.
1 and 23 are the first color horizontal register marks 24,
26 and the first color diagonal register mark 25,2
7 is detected. Therefore, the outputs of the gates 48 and 50 become B and L in FIG. 7, respectively, and become inputs to the mark discrimination circuit 54. And the output C is
Only the detection signal of the first color operating side horizontal register mark 24 is output, and D outputs the detection signal of the operating side diagonal register mark 25.

Also, since the emitter 22 and the receiver 23 detect the drive-side horizontal register mark 26 and the drive-side diagonal register mark 27, the output of the gate 50 becomes L in FIG. 7, which becomes the input to the mark discrimination circuit 58. . The output M outputs only the detection signal of the drive side horizontal direction register mark 26, and the output N outputs the detection signal of the drive side diagonal direction register mark 27. Therefore, the phase difference determination circuit 53 outputs the phase difference between the operating side horizontal register mark 24 and the driving side horizontal register mark 26. Further, the phase difference discrimination circuit 62 detects the operation side diagonal register mark 2.
5 and the drive-side diagonal register mark 27 becomes the output F.

These E and F signals are input to the pulse width detection circuit 54, and the E and F pulse widths shown in FIG. 7 are calculated quantitatively. Next, a specific example of the pulse width detection circuit 54 using a pulse signal generator will be described below.

Now, due to the rotation of the impression cylinder, pulses at regular intervals are generated in the output G from the pulse signal generator 34. When signal E is ON, gate 55 is open and G
The pulse flows to the horizontal mark counter 56, and the gate 55 closes when the signal E turns OFF.
The G pulse is cut off. Therefore, the signal H is obtained by converting the phase difference from the operating side horizontal register mark 24 to the detection of the driving side horizontal register mark 26 into the number of pulses. Then, the output K of the horizontal mark counter 56 becomes the twist amount ε ₉ .

Next, the torsion correcting motor 30 is rotated by this amount of torsion, and the drive side of the plate cylinder is moved in the vertical direction P through the plate cylinder driving device 32 and shaft 33 until the error becomes zero. Further, the twisting amount ε ₉ is displayed on the twisting display lamp 59. On the other hand, the signal F of the phase discrimination circuit 62
However, when ON, the gate 63 opens, a G pulse flows to the diagonal mark counter 57, and the signal F
When is OFF, the gate 63 is closed and the pulse is cut off.

Therefore, the signal J is obtained by converting the phase difference from the operating side diagonal register mark 25 to the detection of the driving side diagonal register mark 27 into the number of pulses. This number of pulses includes ε ₉ , so
The register error ε ₁₀ in the left-right direction Q is obtained by subtracting the number _of pulses corresponding to ε ₉ in the arithmetic unit 60.

Therefore, the two outputs of the horizontal mark counter 56 and the diagonal mark counter 57 are input to the arithmetic unit 60, and the output thereof becomes the misregister amount ε ₁₀ in the left-right direction Q. The left-right direction register correction motor 31 is rotated by this amount of error, and the plate cylinder is moved in the left-right direction through the plate cylinder driving device 32 and shaft 33 until the error becomes zero. Further, the left and right display lamp 61 displays the left and right misregister amount ε ₁₀ . Note that if the register mark is detected again after correcting the amount of twist, the diagonal mark counter 5
The output of 7 becomes ε ₁₀ , and the arithmetic unit 60 becomes unnecessary.
In this way, the amount of twist and the amount of misregistration in the left-right direction can be corrected to zero for the second and subsequent colors as well. Note that similar modifications can be made to register marks such as those shown in FIGS. 8 to 11.

Since the present invention is constructed as explained in detail above, it is possible to automatically move the plate to a predetermined position with a low-cost device (no need for a reference sensor) and no printing paper at all, and to start printing. Paper with normal registration comes out from the first sheet. Further, it is possible to automatically adjust the torsion in the left and right direction without using a reference sensor.

[Brief explanation of drawings]

FIG. 1 is a front view of a sheet-fed printing press to which the device of the present invention is applied, FIG. 2 is a perspective view of the cylinder of FIG. 1 equipped with the device showing an embodiment of the present invention, FIGS. Fifth
The figure is an explanatory diagram showing the amount of error between the register mark and the reference point in Figure 2, Figure 6 is a block circuit diagram showing an embodiment of the present invention, Figure 7 is a pulse waveform diagram,
FIGS. 8, 9, 10, and 11 are explanatory diagrams showing register marks different from those in FIG. 3, respectively. Explanation of the main parts of the figure, 12, 13...plate cylinder, 2
0, 22... Emitter, 21, 23... Light receiver, 2
4, 26...Horizontal register mark, 25, 2
7...Diagonal register mark, 28...Version, 3
0, 31... register correction motor, 53, 62... phase difference discrimination circuit, 54, 58... mark discrimination circuit.

Claims (1)

[Claims] 1 Detecting the horizontal and diagonal register marks provided on the operation side and drive side of each color plate,
The amount of torsion of the plate is detected from the phase difference between the horizontal register mark on the operating side and the horizontal register mark on the driving side, and the horizontal registration error is detected from the phase difference between the diagonal register mark on the operating side and the diagonal register mark on the driving side. 1. A register adjustment device that detects the quantity and adjusts the register by moving a plate cylinder according to the detection signal.