JPS635746B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a platelet machine for offset printing, which is characterized in that it is formed so that the film and the printing plate are brought into close contact quickly and completely. This invention relates to a shortening device.

Conventionally, the film and printing plate of an offset printing plate were brought into close contact, and the film was then exposed and printed on the printing plate. The problem was that the remaining air near the center of the section was not sufficiently removed, making the remaining air blurry and unusable.

The present invention is an invention of a device for shortening the vacuum contact time of an offset printing plate machine, which has been proposed in order to eliminate the above-mentioned drawbacks. That is, in the present invention, a film holder and a film attached to the printing plate are attached to a fixed substrate via an elastic plate, and a film holder and a film attached thereto are disposed opposite each other so as to move back and forth, and the film is adhered to the printing plate, and the film holder is attached to the printing plate. A vacuum pump connected to a three-way solenoid valve is used to extract air from between the film and the printing plate, while an intake pipe is provided through the substrate and the elastic plate to extract air between the printing plate and the film. In the process of further air bleed, intermittent air bleed and air supply are performed on the back side of the printing plate, and the printing plate is intermittently vibrated to promote air bleed between the printing plate and the film,
This invention is an invention of a device for shortening the vacuum contact time of a printing plate machine for offset printing, which is characterized by significantly shortening the time of contact between a printing plate and a film. This can be explained with reference to the drawings as follows.

In the attached drawings, reference numeral 1 denotes a film holder, and a printing device 2 is installed on the back of the film holder 1 so as to move forward and backward, and the periphery of a glass plate 3 is fixed to the front of the film holder 1. The inner end of a flexible packing 4 such as rubber is hermetically fitted to the stepped portion provided on the front surface of the film holder 1, and the outer end of the packing 4 is formed into an expanded portion 5. , the tip of the expanded portion 5 is attached to the printing plate 1
Formed so as to be in close contact with 0. A film 7 on which the developed image 6 has been printed is placed on the front surface of the glass plate 3, adhesive cloth such as sellotape 8 is adhered to the periphery of the film 7 and the glass plate 3, and the film 7 is airtightly attached to the glass plate 3.
to be set up.

A through hole 9 is formed so as to be positioned below the film holder 1 and open on both sides of the film holder 1, and one end of the through hole 9 is connected to the flat part of the expanded portion 5 of the packing 4. When it comes into contact with the printing plate 10, an opening is formed between the printing plate 10 and the film 7, and the other end of the through hole 9 is connected to the film holder 1.
A connection opening is made to one end of a flexible air bleed pipe 11 provided at the rear of the pipe. The other end of the air bleed pipe 11 is connected to the T-shaped connecting pipe 1.
Connect one end of the horizontal part of the connecting pipe 12 to one end of the horizontal part of the connecting pipe 12, and connect one end of the air bleed pipe 13 to the other end of the horizontal part of the connecting pipe 12.
The other end is connected to the suction port of the vacuum pump 14. The printing plate 10 is constructed by attaching a photoresist film to a thin metal plate such as a light alloy having elasticity and flexibility.

A substrate 15 is fixedly mounted opposite to the film holder 1, an elastic plate 16 is provided on the surface of the substrate 15, and several support pieces 17, 17 are provided on the upper and lower ends of the substrate 15.
The printing plate 10 is attached to the elastic plate 16 by adhering an adhesive cloth such as cellophane tape 18 to the periphery of the printing plate 10 and the periphery of the elastic plate 16 to attach the substrate 15.
An elastic plate 16 is airtightly stretched between. The size of the printing plate 10 is such that the film 7 can be printed several times (4 to 12 times) in succession. The printing device 2 is moved vertically and horizontally by a feeding mechanism such as a worm and a worm wheel to print the developed image 6 on the film 7 onto the printing plate 10.

Several through holes 19 are formed in the elastic plate 16, and through holes 20 communicating with the through holes 19 are formed in the substrate 15. An enlarged portion of a funnel-shaped intake pipe 21 having elasticity such as rubber is fitted into the through hole 19, and the enlarged portion of the intake pipe 21 is divided into several sections to form the intake port 2.
2. One end of the "Ko-shaped" connecting pipe 23 or "T-shaped" connecting pipe 24 is connected to the rear end narrow part of the intake pipe 21, and the connecting pipe 23 or 2
4 is connected to one end of a ventilation pipe 25, the other end of the ventilation pipe 25 is connected to one end of a three-way solenoid valve 26,
The other end of the three-way solenoid valve 26 is connected to the vertical end of the connecting pipe 12.

Conductive wires 27 and 28 are connected to the electromagnetic part of the three-way solenoid valve 26.
A timer 29 is attached to the conductive wires 27 and 28 to open and close the valve of the three-way solenoid valve 26 at intervals of about 2 seconds, and the other ends of the conductive wires 27 and 28 are connected to a power source. do. By the operation of the three-way solenoid valve 26, the inside of the ventilation pipe 25 and the intake pipe 21 are evacuated, for example, the pressure is reduced, or the pressure is brought to atmospheric pressure, and when the pressure is reduced to a degree close to vacuum, the printing plate 10 is The printing plate 10 is separated from the film 7 by sucking air from the back side, and then the printing plate 10 is returned to its original state by stopping the suction, and the printing plate 10 is brought into close contact with the film 7, and this is done intermittently. The printing plate 10 is repeatedly vibrated, and this vibration moves the air between the film 7 and the printing plate 10 in the direction of the air bleed pipe 11, promoting air bleed and separating the film 7 and the printing plate 1.
It is formed so that the time of close contact with 0 is significantly shortened. That is, by intermittently separating the printing plate 10 from the film 7 at intervals of about 2 seconds, and alternately bringing the printing plate 10 into close contact with the film 7, the printing plate 10 remains in the center between the printing plate 10 and the film 7. The air between the printing plate 10 and the film 7 is quickly and completely removed by moving the air between the printing plate 10 and the film 7 to the air bleed pipe 11, thereby significantly shortening the time of contact between the printing plate 10 and the film 7, and completely eliminating the air between the printing plate 10 and the film 7. By bringing the printing device 2 close to the film 7 in close contact with the film 7, any part of the developed image 6 can be clearly printed on the film 7. When the printing of the developing image 6 is completed, the printing device 2 is moved back, and then air is sent between the film 7 and the printing plate 10.
The film 7 and the printing plate 10 are separated, the film holder 1 is moved, and the next operation is started.

Since the present invention is constructed as described above, to explain the printing process, first, the film holder 1 located at a distance of about 20 mm from the printing plate 10 should be printed on the printing plate 10 first. Positioning is performed by driving the vertical, left and right feed devices. After this positioning is completed, actuate the air cylinder provided separately to place the film holder 1.
is brought close to the printing plate 10, and the film 7 is brought into contact with the printing plate 10, and the outer edge of the flat part of the expanded part 5 of the packing 4 of the film holder 1 is brought into contact with the printing plate 10, and the printing plate 10 and the film 7 are brought into contact with the printing plate 10. Seal the space airtight. The film holder 1
At the same time that the film 7 starts to approach the printing plate 10, a separately provided micro switch (not shown) is activated to close the circuit of the motor A, and the vacuum pump 14, which is already in operation, moves the printing plate 10. Air between the film 10 and the film 7 is extracted through the through hole 9, the air bleed pipe 11, the connecting pipe 12, and the air bleed pipe 13. Along with the operation of the vacuum pump 14, the timer 29 is activated, the three-way solenoid valve 26 is activated, and the air inlet 22 is brought into a reduced pressure state close to vacuum as described above, and the printing plate 10 is separated from the film 7, or the air is extracted. By stopping the printing plate 10, the printing plate 10 is returned to its original properties, and the printing plate 10 is brought into close contact with the film 7,
By repeating this intermittently and vibrating the printing plate 10, the air between the printing plate 10 and the film 7 is moved in the direction of the air bleed pipe 11, and air bleed is promoted.
By completely eliminating air, the time for adhering the film 7 to the printing plate 10 is significantly shortened, and the adhesion is ensured. ) Next, a printing device 2 operated by a timer is brought close to the film 7 to perform exposure printing. After this printing is completed, a separately provided timer switch stops the operation of the vacuum pump 14, and the pressure between the printing plate 10 and the film 7 is set to atmospheric pressure, and the inside of the intake pipe 21 is set to atmospheric pressure, and the air cylinder is The film holder 1 is then moved back to its original position. To move the film holder 1 to another printing location for the printing plate 10, the feeding mechanism is driven by rotating the location setting dials 32, 32 provided on the operating section 31, and the vertical and horizontal positions are set. It will be automatically executed. The intake pipe 21 is designed to be operated by an approach switch (not shown) provided on the moving shaft of the film holder 1 so that only the intake pipe 21 corresponding to the location where the film holder 1 has moved is operated. be. It is convenient to use the printing device 2 if it is configured to move simultaneously with the movement of the film holder 1. A in the figure is a motor.

Since the present invention is configured as described above, the substrate 15
A printing plate 10 attached to a movable film holder 1 is brought into contact with the printing plate 10 and a film 7
In the process of extracting the air between the two using an air extraction mechanism, a ventilation pipe 25 and a three-way solenoid valve 2 are connected to an intake pipe 21 that penetrates through the base plate 15 and the elastic plate 16 attached thereto.
6 to the vacuum pump 14, and a timer 29 is interposed in the conductors 27 and 28 of the electromagnetic part of the three-way solenoid valve 26, and when the timer 29 is activated, the air is discharged at the intake port 22 of the intake pipe 21. Print version 10
By alternately and intermittently absorbing and releasing air every 2 seconds, the printing plate 10 is subjected to intermittent vibrations, and the air remaining at the center of the contact area between the printing plate 10 and the film 7 is removed. It moves in the direction of the opening of the air bleed pipe 11, promotes air bleed between the printing plate 10 and the film 7, and quickly and completely eliminates the air, so that the air between the printing plate 10 and the film 7 can be removed quickly and completely. Since the adhesion time can be significantly shortened, printing plate work can be streamlined, printing efficiency can be increased, and clear printing plates can be obtained. Also, as before,
There are almost no printing plates that are blurred due to insufficient adhesion, and costs can be reduced. In addition, each operation is accurate and easy to handle, which has the advantage of saving labor. Furthermore, the presence of the elastic plate 16 makes the contact between the printing plate 10 and the film holder 1 soft and elastic, thereby preventing damage to each contact portion and preventing air from accidentally entering the back side of the printing plate 10. , a good printing plate can be obtained without blurring of the developed image printed on the printing plate 10.

[Brief explanation of the drawing]

FIG. 1 is a rear view of the present invention, FIG. 2 is a side view, FIG. 3 is a partially cutaway side view showing the relationship between the substrate and the film holder when viewed from the opposite direction of FIG. 2, and FIG. The figure is an exploded perspective view showing the printing plate and the film holder, and FIG. 5 is a partial perspective view showing the relationship between the elastic plate and the intake pipe.

Claims (1)

[Claims] 1. A printing plate having elasticity and flexibility and provided with a photosensitive film is attached to a fixed substrate via an elastic plate, and a film holder and a film attached to the printing plate are moved back and forth freely. disposed oppositely, the film is adhered to the printing plate, and a vacuum pump connected to a three-way solenoid valve is connected to the film holder to eliminate air between the printing plate and the film; A funnel-shaped,
and an elastic suction pipe is installed through the printing plate, the suction part of the suction pipe is opened on the back side of the printing plate, and the suction pipe is further connected to the vacuum pump which is connected to a three-way solenoid valve operated by a timer. The printing plate is formed to bleed air from the back side thereof, and in the process of bleeding air from between the printing plate and the film, the printing plate is vibrated by intermittently blowing air and supplying air from the back side of the printing plate. A device for shortening the vacuum contact time of a printing plate machine for offset printing, characterized in that the vacuum contact time between the printing plate and the film is significantly shortened by promoting air bleed between the film and the printing plate.