JPS63132242A - Replenisher replenishing device for photosensitive lithographic printing plate developing machine - Google Patents

Abstract

PURPOSE:To prevent generation of an extremely excessive or deficient amt. of replenishment by judging whether there is a need for replenishment or not by using both of the replenishment data according to the area of a lithographic printing plate and the data on the fatigue degree of a developing soln. thereby permitting the exact replenishment. CONSTITUTION:The required amt. of the replenishment per unit area of the lithographic printing plate 34 is preliminarily determined and the processing area is detected by an area detecting means 60. The required amt. of the replenishment with respect to the insertion area is calculated by a means 54 for computing the amt. of the replenishment per area. On the other hand, the fatigue degree of the developing soln. is calculated by fatigue degree detecting sensors 64, 65. Whether there is a need for the replenishment or not is judged in accordance with the fatigue degree of the developing soln. 40 in the replenishment period obtd. by said fatigue degree detecting sensors. An alarm is made by a control means when the fatigue degree measured by said fatigue degree detecting sensors attains the value within the prescribed region. The defective development arising from the difference in the amt. of the replenishment based on the abnormality in the output data, etc., of the area detecting means 60, or the difference in the image area is thereby prevented.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention is a photosensitive device that is used in an automatic developing machine and replenishes a developer replenisher according to the processing area when developing a large number of photosensitive lithographic printing plates. The present invention relates to a developer replenisher replenishing device for a lithographic printing plate developing machine.

[Prior art] When processing a photosensitive lithographic printing plate using an automatic developing machine, the development strength of the developer generally deteriorates as the processing progresses, and if processing is continued, non-image areas of the photosensitive layer will be eluted. The running force of the film decreases significantly, causing poor development.

The factors that cause this development defect are processing fatigue caused by components eluted from the photosensitive layer or active components in the developer being consumed, and in the case of an alkaline developer, carbon dioxide in the air is absorbed over time and a neutralization reaction occurs. If the active ingredient in the developer is alcohol, the alcohol evaporates over time and fatigue occurs over time.

There are various means for detecting the degree of fatigue of the developing solution. The sensor measures and detects the degree of elution of the photosensitive layer in the non-image area of the photosensitive lithographic printing plate, and when this detected value drops to a predetermined level, the replenishing device is activated to dispense a certain amount of developer replenisher. Some are designed to be added to the developer.

This is because as the degree of fatigue of the developer increases, the elution rate of the sensitive film in the non-image area slows down, and the measured value (e.g.
This is based on the principle that the residual membrane impedance value (residual membrane impedance value) changes.

[Problems to be Solved by the Invention] However, if the type of photosensitive lithographic printing plate to be processed or the thickness of the photoresist film differs, the predetermined level (replenishment start level) will differ. This may result in over-replenishment or under-replenishment.

In addition, if a part of the photosensitive layer of the photosensitive lithographic printing plate (for example, only the central part) is exposed and there is some unprinted area around the periphery, the fatigue detection sensor (elution degree detection sensor) will detect the image part. Therefore, the replenishment amount will be over compared to the required replenishment amount.

Furthermore, if proper data cannot be obtained due to poor detection such as disconnection of the signal line of the fatigue level detection sensor or deposition of deposits on the detection terminal, optimal replenishment of the replenishment fluid may not be performed.

Therefore, when replenishment is performed based only on the output of the fatigue level detection sensor, if there is an abnormality in the detected data, the amount of replenishment may be extremely excessive or insufficient. On the other hand, if replenishment is performed based only on the insertion area of the photosensitive lithographic printing plate, it is unlikely that the replenishment amount will be extremely excessive or insufficient, or the difference in replenishment by one point due to the difference in the area of the image area can be corrected by iE. I can't think of anything to do. According to experimental values, if the tank volume 4 is overfilled by 14% or more, the photosensitive diagonal printing plate cannot be processed normally.

The present invention takes into consideration the above-mentioned 'f>actuality' and uses both replenishment data according to the area of the photosensitive lithographic printing plate and data on the degree of fatigue of the developer to determine whether replenishment is possible or not. The object of the present invention is to provide a replenisher replenishing device for a photosensitive lithographic printing plate developing machine that allows accurate replenishment by making one cut and that does not cause excessive or insufficient replenishment.

[Means for Solving the Problems] The replenisher replenishing device for a photosensitive lithographic printing plate developing machine according to the present invention comprises: an area detecting means for detecting the development processing area of a photosensitive printing plate; a replenishment calculation means for calculating replenishment -1 of the replenisher according to the processing area obtained by the means; a fatigue level detection sensor disposed in the developing section for detecting the degree of fatigue of the developer; and a predetermined area detection means. (The processing area is detected and the degree of fatigue of the developer at that time), (Then, if it is determined that replenishment of the replenisher is necessary, the amount of replenishment obtained from the above-mentioned replenishment field calculation step is added to the developer. a replenishment stage for replenishing the replenisher, and a control-L stage for deactivating the fatigue level by one level when the fatigue level obtained by the fatigue level detection sensor falls within a predetermined range.

[Function] Replenishment of replenisher to the developer is performed by replenishing the replenishment amount obtained by the area detection stage located on the entrance side of the developing section.

This replenishment) is achieved by predetermining the necessary replenishment amount per unit area of the photosensitive V printing plate, and by detecting the processing area with the area detection means, the area replenishment amount calculation means The required replenishment amount is calculated. on the other hand,
A fatigue level detection sensor disposed in the developing section calculates the fatigue level of the developer. Since it is determined whether or not replenishment is necessary based on the fatigue level of the developer at the replenishment time obtained by the fatigue level detection sensor, over-replenishment or insufficient replenishment can be prevented. Further, when the fatigue level measured by the fatigue level detection sensor falls within a predetermined range, the control means issues a warning. This makes it possible to prevent development defects caused by abnormalities in the output data of the area detection means or by differences in replenishment amounts based on differences in image area.

[Example] FIG. 1(A) shows the photosensitive planographic printing plate development 4I! according to this example. 30 is shown.

A pair of insertion rollers 32 are disposed on the insertion side of the developing section 31 of the photosensitive planographic printing plate developing device 30.

The photosensitive planographic printing plate 34 is held between the insertion rollers 32 and conveyed in the direction indicated by the first +3 (A) arrow by the driving force of a driving means (not shown).

A pair of discharge rollers 36 having the same shape as the insertion roller 32 are disposed on the discharge side of the developing section 31, and a pair of discharge rollers 36 having the same shape as the insertion roller 32 are arranged.
4 is conveyed by the insertion roller 32, and when the tip reaches the discharge roller 36, it is clamped and sent to the next process. Insertion roller 32 and ejection roller 36
A pair of intermediate rollers 29 are disposed between the two and guide the photosensitive planographic printing plate 34. Further, a brush roller 27 is arranged between the intermediate roller 29 and the discharge roller 36,
It is adapted to come into contact with the photosensitive lithographic printing plate 34 passing therethrough.

A plurality of injectors 38 are disposed above the photosensitive lithographic printing plate transport path of the developing section 31 and serve as discharge ports for the developer 40 . The injector 38 is connected to a receptacle for a developer 40 disposed below the developing section 31 through a circulating groove vibrator 42 and to the bottom of the tray 44 . A pump 46 is interposed in the middle of the circulation vibrator 42, and pumps out the developer 40 from the tray 44 and sends it to the injector 38.

Further, the outlet of the replenishment vibrator 48 is disposed in the opening of the tray 44, and the rear end of the receptacle is communicated with the replenishment tank 50. A pump 52 is interposed in the middle of the replenishment vibrator 48, and when a signal from a microcomputer 54 is received and power is supplied via a pump operation relay 56, the replenisher 58 is pumped from the replenisher tank.
It is designed to be replenished to the receiver @44.

Connected to the microcomputer 54 are a signal line 62 of an area detection means 6o that detects the insertion state of the photosensitive planographic printing plate 34 and a signal line 66 of a fatigue level detection sensor 64 that measures the fatigue level of the developer 40 as impedance. has been done. Further, a fatigue level detection sensor 65 identical to the fatigue level detection sensor 64 is arranged at a position slightly separated from the fatigue level detection sensor 64, and its signal line 67 is also connected to the microcomputer 54. That is, the fatigue level detection sensor detects the position where the photoresist film is being melted (fatigue level detection sensor 64) and the position where it is completely dissolved (fatigue level detection sensor 64).
5) are provided in two locations.

Note that instead of the fatigue level detection sensor 65, a sensor is provided near the entrance of the developing section at a position before the photoresist film starts to dissolve, and the sensor is installed at a position near the entrance of the developing section, which contains the support of the photosensitive lithographic printing plate, the photoresist film, and the developer. The impedance of the system may be measured first, and the fatigue level detection sensor 64 may measure changes in the impedance of the system. Further, even if the accuracy is slightly lower or the fatigue level detection sensor 64 is provided at a position where the photoresist film surface is in the middle of melting, good results can be obtained when combined with area replenishment.

The area detection means 60 is disposed upstream of the insertion roller 32 of the developing section 31, and inputs and outputs high-level signals from the time when the leading edge of the photosensitive planographic printing plate 34 is conveyed until the trailing edge thereof passes. The signal is output to the capotro 8, and the other low level signals are output to the input/output capotro 8 (see FIG. 2).

As shown in FIG. 1(B), this area detection p stage 60 is composed of a plurality of photoelectric switches 69 arranged along the width direction of the photosensitive planographic printing plate 34. The photoelectric switch 69 located outside the width direction end of the photosensitive planographic printing plate 34 is kept at a low level even when the photosensitive planographic printing plate 34 is conveyed, so that the widthwise dimension of the photosensitive planographic printing plate 34 can be read. . Further, the conveyance speed of the photosensitive planographic printing plate 34 is predetermined, and the photoelectric switch 6
The length dimension of the photosensitive planographic printing plate can be easily obtained from the time in the high level state and the conveyance speed in step 9, and the area of the photosensitive planographic printing plate 34 can be calculated by multiplying this length dimension and the width dimension. It's like that.

Since the appropriate replenishment amount of the replenisher 58 is approximately proportional to the processing area of the photosensitive planographic printing plate 34, the replenishment time Q is determined according to the processing area.
is expressed by the following equation.

Q=W-Vt-8/U where, Q: Replenishment time W: Width dimension of the photosensitive planographic printing plate V: Conveyance speed t of the photosensitive planographic printing plate: Conveyance time of the photosensitive planographic printing plate S: Medium Required replenishment amount per surface area U: Pump flow rate This calculation is performed every 60 seconds after the transport time t of the photosensitive printing plate, and each time, the replenishment time Q is determined by the replenishment pump operation. It is set to the timer for

In response to this signal, the replenishment fluid operation timer 77 supplies 'it1M' to the pump operation relay 56 for the replenishment time Q, so that the replenishment fluid 58 is replenished.

A pair of electrodes 64A, 64B and an electrode 65 are provided at the tips of the fatigue level detection sensor 64 and the fatigue level detection sensor 65, respectively.
A, 65B are provided. Here, when the developer 40 is injected from the injector 38, the developer 40 stays above the photosensitive layer of the photosensitive lithographic printing plate 34, and the electrode 64
A, 64B are immersed in the developer, and electrodes 65A,
65B is also immersed in the developer, so that the impedance of the system to be measured (the system containing the support of the photosensitive lithographic printing plate 34, the remaining photosensitive film, and the developer) can be measured. Here, the microcomputer 54 calculates the impedance value R of only the remaining photoresist film by taking the difference or ratio of the measured values of the two fatigue level detection sensors 64 and 65.

In place of the fatigue level detection sensor 65, a sensor is provided at a position near the entrance of the developing section before the photoresist film begins to dissolve, and a fatigue level detection sensor 64 is provided at a position where the photoresist film is in the middle of dissolution.
By taking the difference in impedance between the two, it is possible to obtain the impedance value of only the dissolved photoresist film, and the degree of fatigue of the developer may be calculated from this.

As shown in FIG.
It is designed to be input to the input/output capotro 8 via. This impedance value R is measured using the photosensitive planographic printing plate 3.
This is carried out after a predetermined period of time after the area detecting means 60 detects the tip of the 4, and is input to the CPU 74. The storage means 76 (ROM) stores three types of impedance threshold levels (first threshold level R1, second threshold level R2, and third threshold level R3). It is divided into 13 areas (■, ■, ■, ■). The CPU 74 compares the measured value of the fatigue level detection sensor 64 with each threshold value (
(See Figure 4).

In this case, the measurement value of the fatigue level detection sensor 64 alone may be used, but the fatigue level detection sensor 64 and the fatigue level detection sensor 65, or
It is preferable to use a measurement value obtained by a combination of the fatigue level detection sensor 64 and a sensor provided at a position upstream of the fatigue level detection sensor 64 before the photoresist film begins to dissolve.

The operation of this embodiment will be explained below with reference to the flowchart shown in FIG.

First, when it is determined in step 100 that the power is on, the device is initialized in step 102 and the transport time t of the photosensitive planographic printing plate 34 is set to 60 seconds.

Next, in step 104, it is determined whether or not the photosensitive planographic printing plate 34 is being transported. This can be easily determined by checking the on/off state of the photoelectric switch 69. If a negative determination is made in step 104, the process moves to step 106, and if the timer T is running, it is temporarily stopped, and the process moves to step 104. If an affirmative determination is made in step 104, the process moves to step 108 and the operation of timer T is started. That is, in steps 104, 106, and 10B, the value of timer T can be added only while the photosensitive planographic printing plate 34 is being conveyed.

When the operation of timer T is started in step 10B, it is then determined in step 1) 0 whether or not the value of timer T has reached t (60 seconds), and if it is affirmative, the process moves to step 1) 2. , the operation of timer T is stopped. Also, step llO
If the determination is negative, the process moves to step 104. After the operation of the timer T is stopped, the process moves to step 1)4, where the degree of fatigue of the developer 40 or the impedance value R is measured. This impedance value R is calculated by the microcomputer 54 as the impedance value R of only the remaining photosensitive film or only the 1st pattern of dissolved photosensitive film based on the measured values of the two fatigue level detection sensors 64 and 65.
It is possible to prevent adverse effects such as fluctuations in the impedance value due to the aluminum plate or the like used in No. 4.

Once the impedance value R is measured, the first threshold level R1 is read in step 1)6, and then step 1)
)8, this R1 and R are compared. If it is determined that R1≦R, it is determined that the impedance (i) is in the region ■, that is, in the high sensitivity region (see graph X in Figure 4, p! A).
, the process moves to step 120. In step 120, the replenishment pump 52 is stopped, and then in step 122, the warning device 82 is activated. As a result, one worker can use 4 developer fluids.
0 Abnormalities can be confirmed.

If R1<R, the process moves to step 124, where the second threshold level R2 is read, and then, in step 126, R2 and R are compared. Here, if it is determined that R2≧R, the impedance value R can be determined to be in the region @, that is, the low sensitivity region (see graph Y in Figure 4), and step 1
Move to 20. If R2<H, the process moves to step 128, where the third threshold level R3 is read, and then, in step 130, R3 and R are compared. Here, if it is determined that R3≦R, it is determined that the impedance value R is in the region (2), that is, a recoverable low sensitivity region, and the process moves to step 132.

In steps 132, 134, 136, and 138, the width dimension W and conveyance speed V are calculated, and the required replenishment QS per unit area and pump flow rate rpU are read, and in step 140, the replenishment time Q is calculated. This replenishment time Q
When this is calculated, the replenishment pump 52 is activated in step 142, and replenishment of the replenisher 58 is started.Next, in step 144, it is determined whether a time Q has elapsed since the replenishment was started. If 9 seconds have elapsed, the process moves to step 146, where the operation of the replenishment pump 52 is stopped, and then step 1
After the timer T is reset at step 48, the process moves to step 104. If 9 seconds have not elapsed in step 144,
Repeat step 144 until 9 seconds have elapsed.

Further, if it is determined in step 130 that R3<R, it can be determined that the impedance value R is within the region (2), that is, within the appropriate sensitivity, and the process proceeds to step 104, where the photosensitive mo printing plate 34 is detected. .

In this way, normally, the replenisher is replenished for 5 days according to the processing area of the photosensitive planographic printing plate 34, and in addition to this, the developer is added for 5 days.
Since we are measuring the impedance value of
As shown in the graph Z, the impedance value R of the developer 40 is kept almost constant based on the third threshold level R3, and the impedance value R of the developer 40 is maintained at a level that does not interfere with the processing of the photosensitive printing plate 34. It is possible to sequentially monitor whether the sensitivity of the replenishment becomes high or low, and in the event of an abnormality, the operation of the replenishment pump is forcibly stopped and a warning is issued, thereby making it possible to prevent processing defects.

In this embodiment, a plurality of photoelectric switches 69 are applied to the surface-setting detection means 60, or a plurality of limit switches are arranged, and the limit switches are turned on and off according to the conveyance of the photosensitive planographic printing plate. Other means of detecting the area of thatch may also be used.

In addition, the width direction dimensions of various types of photosensitive lithographic printing plates are input in advance by the operator into the storage L stage (RAM) and stored, and the necessary data is stored each time on the keyboard 54A of the microcomputer 54 (see Fig. 2). (see imaginary line).

Furthermore, the plate type of the photosensitive lithographic printing plate can be read using a bar code attached to the surface of the photosensitive film, and the amount of replenishment per unit time can be automatically set.

Further, the control means may also stop the pump 52 or may only provide a warning. The warning device is not limited to an alarm, but may also be an indicator such as a blinking lamp to notify the worker of an abnormality.

[Effects of the Invention] As explained above, the replenisher replenishing device for a photosensitive lithographic printing plate developing machine according to the present invention is capable of replenishing when the data value obtained by the fatigue level detection sensor falls within a predetermined range! ! By having a control means to notify the developer, it is possible to monitor the amount of replenisher to be replenished according to the area of the photosensitive planographic printing plate while sequentially detecting the degree of fatigue of the developer, and it is possible to perform accurate replenishment. It has this excellent effect.

[Brief explanation of the drawing]

FIG. 1(A) is a front view of the photosensitive planographic printing plate developing machine according to this embodiment, FIG. 1(CB) is a perspective view of a photoelectric switch constituting a part of the area detection means, and FIG. FIG. 3 is a block diagram of a replenisher replenishing device applied to a lithographic printing plate developing machine, FIG. 3 is a flowchart explaining the operation of this embodiment, and FIG. 4 is a graph showing the range of impedance value R of the developer. 30...Photosensitive lithographic printing plate developing machine. 31... Developing section, 40... Developer, 54... Microcomputer, 60... Area detection means, 64.65... Fatigue level detection sensor, 82... Warning device. Elementary 1 Figure (B) Figure 4

Claims (4)

[Claims] (1) An area detection means for detecting the development processing area of the photosensitive planographic printing plate, and a replenishment amount calculation means for calculating the replenishment amount of the replenisher according to the processing area obtained by the area detection means, arranged in the developing section. When a predetermined processing area is detected by the fatigue level detection sensor that detects the fatigue level of the developer and the area detection means, and it is determined that replenishment of the replenisher is necessary based on the fatigue level of the developer at that time. a replenishment means for replenishing the developer with the replenishment amount obtained from the replenishment amount calculation means, and a control means for warning when the fatigue level obtained by the fatigue level detection sensor falls within a predetermined range; A replenisher replenishing device for a photosensitive lithographic printing plate developing machine. (2) The photosensitive lithographic printing plate development according to claim (1), wherein the control means outputs a control signal at the time of warning, and uses this control signal to stop the operation of the replenishment pump. Machine replenishment fluid replenishment device. (3) The degree of fatigue is an impedance value R of the developer, and this impedance value R is a first threshold level indicating that the developer is in a high sensitivity state or a first threshold level indicating that the developer is in a low sensitivity state. Claims (1) or (1) above, characterized in that when the second threshold level indicated by
2) A replenisher replenishing device for a photosensitive lithographic printing plate developer according to item 2). (4) A third threshold level is provided between the first threshold level and the second threshold level, and the impedance value R is such that the second threshold level <R≦ The replenisher replenishing device for a photosensitive lithographic printing plate developing machine according to claim 3, wherein a predetermined amount of replenisher is refilled when the third threshold level is reached.