JPH0451813B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention provides a printing stand on which a photosensitive material is placed, an upper frame portion having a transparent plate and opening/closing with respect to the upper surface of the printing stand. The present invention relates to a printing device comprising a printing light source disposed at an appropriate location.

<Prior Art> An example of a conventional printing apparatus is shown in FIG. 6 and will be described below.

A rectangular frame 4 is rotatably attached to the rear edge of the printing table 2, which is constructed by pasting a soft sheet on the top surface of the main body 1, via a hinge 3. An upper frame portion 6 is configured to hold the plate 5 and to open and close the upper surface of the printing table 2. A rubber packing 7 is attached to the periphery of the printing table 2.

A telescopic support member 8 such as a gas spring is stretched between the upper frame portion 6 and the main body 1 to facilitate opening and closing of the upper frame portion 6. The printing table 2 is provided with an exhaust port 9 for evacuating the space formed by the printing table 2, the upper frame portion 6 closed to the printing table 2, and the rubber packing 7.

A printing light source 10 is disposed above the printing table 2 across the opening/closing space of the upper frame portion 6. Reference numeral 11 denotes an operating handle attached to the upper frame portion 6.

When performing baking, place the
A photosensitive material such as a PS plate is placed, an original film is placed on top of the photosensitive material, and the upper frame portion 6 is closed. Then, the space is brought into a vacuum state by vacuum suction from the exhaust port 9, and after the original film and the photosensitive material are brought into close contact with each other under vacuum, the printing light source 1
0 is turned on to print the image on the original film onto the photosensitive material.

<Problems to be Solved by the Invention> However, the conventional example having such a configuration has the following problems.

When the upper frame part 6 is closed, there is a possibility that the original film may be misaligned due to the wind pressure generated when the upper frame part 6 approaches the printing table 2. To avoid this, it is best to close slowly at least before closing.

However, it is troublesome to close it slowly by manual operation, and because it is closed too quickly, there is a problem that the original film is likely to shift.

On the other hand, as a device configured to elastically catch the upper frame before closing and close at a relatively low speed, there is the "easel for enlarger printing machine" disclosed in Japanese Utility Model Publication No. 48-17290, and ``Top frame automatic closing mechanism for vacuum baking frames, etc.'' disclosed in Japanese Patent No. 16191 has been proposed.

The device described in Japanese Utility Model Publication No. 48-17290 has a cylinder whose base end is slidably connected to a guide groove provided in the front and back direction on the side surface of a base plate, and which slides forward and backward along the axis of the cylinder. On the side frame of an easel (corresponding to the upper frame), the rod is inserted loosely and the retractable sliding rod is pressed outward along the axis using a bullet, and the base end is pivotally mounted on the top surface of the base plate so that it can rise and fall freely. The outer end of the above-mentioned forward/retractable sliding rod is pivotally connected.

In addition, the device described in Utility Model Publication No. 57-16191 is
a rotary hook pivotally attached to one frame of a pair of upper and lower frames hinged to be openable and closable, and provided with two protrusions;
an elastic body that urges the rotary hook to rotate in a direction away from the dead center with the dead center position as a boundary; to rotate the rotary hook beyond the dead center position, and
and an engagement lever that is biased so as to engage with the protrusions of and close the pair of frames.

The above two devices utilize an elastic body to elastically receive the upper frame portion before closing, and then close the upper frame portion by manual operation against the biasing force of the elastic body. This prevents the upper frame from closing suddenly.

However, even with both of the devices described above, if the upper frame is strongly closed by an inexperienced worker, the closing speed of the upper frame becomes considerably faster, although it is resisted by the elastic body. There is a risk that the original film will shift due to the wind pressure. To prevent this, it is necessary to increase the biasing force of the elastic body, but this has the disadvantage of worsening operability. Furthermore, according to the device described in Japanese Utility Model Publication No. 57-16191, after the rotary hook passes the dead center position, the upper frame is accelerated and closed by the biasing force of the elastic body. There is also a risk that the original film may shift due to the wind pressure.

The present invention has been made in view of the above circumstances, and an object of the present invention is to reliably prevent the original film from shifting when the upper frame portion is closed.

<Means for solving the problems> In order to achieve such an object, the present invention has the following features:
It has the following structure.

That is, the present invention comprises a printing table on which a photosensitive material is placed, an upper frame portion having a light-transmitting plate and opening/closing with respect to the upper surface of the printing table, and a printing light source disposed at an appropriate position. A printing device comprising: a cam follower attached to the upper frame; an inner cam attached to the printing table side for receiving the cam follower; an outer cam that is attached to the printing table side so as to be rotated integrally with the cam and swings an opening that allows the cam follower to enter; a drive mechanism that drives and rotates the rotary drive shaft at a low speed; It is prepared.

<Function> The function of the configuration of the present invention is as follows.

When the upper frame is closed, the cam follower attached to the upper frame first passes through the opening of the outer cam and comes into contact with the inner cam, so that the inner cam closes the upper frame. I can accept it. Next, when the rotary drive shaft is driven to rotate at a low speed by the drive mechanism, the inner cam and outer cam rotate integrally, and the cam follower is guided by the passage between the inner cam and the outer cam and moves downward. As a result, the upper frame portion is slowly closed.

<Example> Hereinafter, an example of the present invention will be described in detail based on the drawings.

1 to 3 relate to one embodiment of the present invention, in which FIG. 1 is a perspective view of the printing device, FIG. 2 is a partially cutaway side view of the main part showing a state in which the upper frame is received, FIG. 3 is a partially cutaway side view of main parts showing a state in which the upper frame is closed.

In these figures, the same symbols as those shown in FIG. 6 according to the conventional example are also used in this embodiment.
Refers to the same parts, parts, etc. indicated by the symbol. Furthermore, unless otherwise specified, the present embodiment and the conventional example have similar configurations in terms of arrangement, connection relationship, and the like. Note that the printing light source 10 is not shown.

The configurations of this embodiment that differ from the conventional example are as follows.

Cam followers 12 are attached to the left and right sides of the front end of the upper frame portion 6 . On the other hand, the main body 1 having the printing table 2 is provided with double cams 13 on both left and right sides of the front end thereof.

Both double cams 13 are fixed to both ends of a cam drive shaft 15 which is rotatably supported by the main body 1 via a bearing 14. A pulley 17 is fixed to the output shaft of a motor 16 that is attached to the main body 1 and rotates at a relatively low speed.
A transmission belt 19 is stretched between the cam drive shaft 15 and a pulley 18 fixed to the cam drive shaft 15.

Each double cam 13 includes an inner cam 20 and an outer cam 21.
and an end plate 22 that integrally connects the inner cam 20 and outer cam 21. Inner cam 20
A cam drive shaft 15 is eccentrically penetrated and fixed to the end plate 22.

As shown in FIGS. 2 and 3, the inner cam 2
The outer circumferential surface of the outer cam 20 and the inner circumferential surface of the outer cam 21 have substantially circular similar shapes, and the gap between the two cams 20 and 21 serves as a passage 23 of the cam follower 12. The width of this passage 23 is approximately equal to the diameter of the cam follower 12. The outer cam 21 is formed with an opening 24 that allows the cam follower 12 to enter so that it is received by the inner cam 20.

A receiving limit switch LS1 is provided on the side plate of the main body 1 to detect that the upper frame portion 6 is received before closing.
A lever 25 for operating LS1 is attached to the upper frame portion 6. Further, a closing limit switch LS2 around the outer cam 21 detects the completion of closing of the upper frame portion 6 to the main body 1, and
An opening permission limit switch LS3 is provided for detecting that the opening of the opening is permitted.

FIG. 4 is a block diagram showing a control system in the printing apparatus of this embodiment.

The three limit switches LS1, LS2,
The LS3, an integrated light meter 26, a data input device (keyboard) 27, and a start switch 28 are connected to a CPU 30 of a microcomputer via an input interface 29.

A vacuum pump drive device 32 that drives a vacuum pump 31 communicating with the exhaust port 9, a motor drive device 33 that drives the motor 16 for driving the double cam 13, and a light source drive device 34 that drives the printing light source 10. and via the output interface 35
Connected to CPU30. 36 is ROM, 37
is RAM.

The rest of the configuration is the same as the conventional example, so the explanation will be omitted.

Next, the operation of this embodiment will be explained based on the flowchart of FIG.

A photosensitive material is placed on the top surface of the printing table 2, and an original film is superimposed on the top surface of the photosensitive material.
The data input device 27 is operated to write data on the vacuum suction time and data on the baking time into the RAM 37. Next, the upper frame portion 6 is closed by manual operation. At this time, the opening 24 of the outer cam 21 faces upward.

The cam follower 12 of the upper frame part 6 enters through the opening 24 of the outer cam 21 and comes into contact with the outer circumferential surface of the inner cam 20, and the upper frame part 6 is temporarily received just before closing against the printing table 2 (see FIG. 2). Therefore,
No wind pressure is generated in the space between the printing table 2 and the upper frame portion 6, or even if wind pressure is generated, it is relatively weak, and displacement of the original film relative to the photosensitive material is prevented.

Note that the gap between the printing table 2 and the upper frame 6 when the upper frame 6 is received without causing wind pressure depends on the size of the upper frame 6, etc., but usually L = 25 at the front end side. ~35mm.

At the timing when the cam follower 12 (upper frame portion 6) is received by the inner cam 20, the lever 25 acts on the receiving limit switch LS1, and the receiving limit switch LS1 is turned on.

During this time, the CPU 30 waits for the catch limit switch LS1 to turn on in step S1, and when it turns on, proceeds to step S2 and turns on the start switch 28.
Wait until it turns on. When the start switch 28 disposed on the operation panel is turned on by manual operation, the process proceeds to step S3 to drive the motor 16 in the forward rotation direction, and waits for the closing limit switch LS2 to be turned on in step S4.

The double cams 13 on both sides are rotated by the drive of the motor 16 via the pulley 17, transmission belt 19, pulley 18, and cam drive shaft 15, and the cam follower 12 is drawn into the passage 23 in the double cam 13. .

That is, the cam follower 1 in the inner cam 20
The contact point of 2 escapes downward and the cam follower 1
2 is allowed to move downward, and the outer cam 21
presses the cam follower 12 from the upper side to the lower side thereof, so as the double cam 13 rotates, the cam follower 12 and thus the upper frame portion 6 are gradually moved in the closing direction.

At this time, the inner cam 20 causes the cam follower 1 to
Since the upper frame part 6 is gradually allowed to move downward while supporting the upper frame part 2, the upper frame part 6 can be moved slowly toward the closing direction, and there is no need to generate wind pressure. Therefore, the original film is prevented from shifting even during the closing operation at this final stage.

When the upper frame portion 6 is completely closed to the printing table 2 in this way (see FIG. 3), the closing limit switch LS2 is turned on at that timing. Then, the process advances from step S4 to step S5, and the drive of the motor 16 is stopped. Next, in step S6, the vacuum pump 31 is driven and the air in the space surrounded by the upper frame portion 6, printing table 2, and rubber packing 7 is exhausted by vacuum suction from the exhaust port 9.

By repeating steps S7 and S8, RAM37
The elapsed time is subtracted from the vacuum suction time stored in , and when the subtraction result becomes zero, the process advances to step S9. During this time, vacuum suction is continued to maintain vacuum contact between the original film and the photosensitive material.

In step S9, the burning light source 10 is turned on, and by repeating steps S10 and S11, the elapsed time is subtracted from the burning time stored in the RAM 37. When the subtraction result becomes zero, the process is started.
Proceeding to S12, the printing light source 10 is turned off. In this way, the image on the original film is printed onto the photosensitive material.

Then, in the next step S13, the vacuum pump 31 is stopped. That is, after the printing is completed, the vacuum suction is stopped and the close contact between the original film and the photosensitive material is released.

In step S14, the motor 16 is driven in the reverse direction, and in step S15, the open limit switch is activated.
Wait for LS3 to turn on.

The double cams 13 on both sides are reversed by the reverse drive of the motor 16, and the cam follower 12 located in the middle of the passage 23 of the double cam 13 relatively comes out toward the opening 24 side of the outer cam 21. . Outer cam 21
When the opening 24 of is at the top (see Figure 2),
The outer periphery of the outer cam 21 is an open limit switch.
Turn on LS3. As a result, the process advances to step S16 and the motor 16 is stopped.

Although the light source has been described as being placed above the printing table, it is not limited to this; it may be placed inside (below) the printing table, or it may be placed separately from the printing table. Needless to say, it is acceptable to do so.

In addition, although the cam drive shaft 15 is automatically rotated by the motor 16, the present invention is not limited to this. For example, if a handle or the like is attached and the rotational force is transmitted to the cam drive shaft by manual operation, all of the opening and closing of the upper frame can be done. It is also possible to perform the operations manually.

<Effects of the invention> According to the present invention, the following effects are exhibited.

That is, since the cam follower attached to the upper frame portion is brought into contact with the inner cam before closing, even if the upper frame portion is closed quite strongly, the upper frame portion will be reliably received before closing. Moreover, after the upper frame is received, the inner cam and outer cam are rotated together at low speed to guide the cam follower downward, thereby closing the upper frame at low speed. Almost no wind pressure is generated when the section is closed.

Therefore, according to the present invention, unlike conventional devices, there is no fear that the original film will shift due to wind pressure caused by the upper frame being strongly closed, and even if an operator who is inexperienced with the operation operates the original film, the original film will not shift. It is possible to reliably prevent the film from shifting.

[Brief explanation of the drawing]

1 to 4 relate to one embodiment of the present invention, in which FIG. 1 is a perspective view of the printing device, FIG. 2 is a partially cutaway side view of the main part showing a state in which the upper frame is received, FIG. 3 is a partially cutaway side view of essential parts showing a state in which the upper frame is closed, FIG. 4 is a block diagram showing the control system of the printing device, and FIG. 5 is a flowchart for explaining the operation. Further, FIG. 6 is a perspective view of a conventional printing device. 2...Printing stand, 5...Translucent plate, 6...Upper frame,
10...Light source for printing, 12...Cam follower, 1
5...Cam drive shaft, 16...Motor, 20...Inner cam, 21...Outer cam, 24...Opening.

Claims (1)

[Scope of Claims] 1. A printing table on which a photosensitive material is placed, an upper frame portion having a transparent plate and opening/closing with respect to the upper surface of the printing table, and a printing light source disposed at an appropriate position. A printing device comprising: a cam follower attached to the upper frame; an inner cam attached to the printing table side for receiving the cam follower; an outer cam that is attached to the printing table side so as to be rotated integrally with the inner cam and has an opening that allows the cam follower to enter; and a drive mechanism that drives and rotates the rotary drive shaft at a low speed. Equipped with a printing device.