JPH036441Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field This invention relates to an ink remaining amount detection device for an ink container that supplies ink to an ink reservoir formed by an ink supply roller and a doctor roller in a stencil printing machine.

BACKGROUND ART In general, as shown in FIG. 3, in a stencil printing machine, ink 24 in an ink reservoir 23 formed by an ink supply roller 21 and a doctor roller 22 is transferred to a plate cylinder 25 by rotation of an ink supply roller 21. When the ink 24 falls below a predetermined amount, the ink sensor 26 detects this and operates the ink pump 27 to supply ink from the ink container 28 to the ink reservoir 23. . When the ink container 28 runs out of ink, the ink container 28 is replaced with a new one. The contact 31 is moved from the position shown by the chain line to the position shown by the solid line by utilizing the deformation of the container, which changes from the shape shown by the chain line to the position shown by the solid line, and the rear end 31a of the contact 31 is brought into contact with the micro switch 32. to detect when the ink is running out.

However, the deformation of the ink container due to the decrease in ink is irregular, making it impossible to reliably detect the absence of ink, and the use of microswitches and contacts leads to various drawbacks, such as being expensive.

Purpose The purpose of this invention is to provide an ink remaining amount detection device for an ink container that can eliminate the above-mentioned drawbacks.

Configuration In order to achieve the above object, this invention detects when the amount of ink in the ink reservoir formed by the ink supply roller and the doctor roller becomes less than a predetermined lower limit value, outputs a detection signal, and outputs a detection signal. an ink sensor that stops outputting when the upper limit value of The ink pump operates every time a signal is input and supplies ink from the ink container to the ink reservoir, and the detection signal and pulse signal can be input simultaneously, and while the pulse signal is input, the pulse A counter that counts the number of inks and resets the count when the detection signal stops, and a counter that resets the count when the detection signal stops, and when the ink amount becomes below the lower limit value, the ink amount reaches the upper limit value after the detection signal is output. The number of times the ink pump should be operated until the output stops is set in advance, and the count counted by the counter is compared with the preset number of times the ink pump is operated, and the number of times the ink pump is operated is determined in advance. a comparator that outputs a no-remaining signal indicating that there is no ink remaining in the ink container when the number of operations exceeds the preset number of operations; and a no-remaining signal output from the comparator. The control device is provided with means for alarming or displaying, and when the control device receives the no-remaining signal output from the comparator, it stops inputting pulses to the ink pump.

Hereinafter, embodiments of this invention will be described based on the drawings.

In FIG. 1, reference numeral 1 denotes a control that inputs the detection signal output from the ink sensor 26 and outputs a pulse signal at predetermined intervals during the input period to operate the ink pump 27 at predetermined intervals, as in the conventional case. A device 2 is a counter that inputs the operating signal and counts the number of inputs, and resets the count when the detection signal is input and the input stops; 3, an ink sensor 26 is connected to the ink reservoir portion 23; The ink pump 27 is operated until the ink reaches a predetermined amount after detecting that the amount of ink is below a predetermined amount. The number of operations is compared with the number of operations, and when the counted number is equal to or greater than the set number of operations, a signal indicating that there is no remaining ink is output. Further, when the control device 1 receives an ink-free signal, it stops outputting the pulse signal. In addition, the same numbers as in Figure 3 have been given to the same parts, so
The explanation will be omitted.

Next, the operation of the embodiment constructed as described above will be explained.

When the amount of ink in the ink reservoir 23 decreases to a predetermined amount or less due to printing, the ink sensor 26 detects this and outputs a detection signal as shown in FIG. 2 (time t1). When the control device 1 receives the detection signal, it outputs a pulse signal at predetermined intervals, and the ink pump 27 operates every time the pulse signal is input to pump ink from the ink container 28 into the ink reservoir 2.
Supply to 3. When the amount of ink in the ink reservoir 23 exceeds a predetermined amount, the output of the detection signal from the ink sensor 26 stops (t2 in FIG. 2), and the output of the pulse signal from the control device 1 stops. At this time, the counter 2 counts the number of pulse signals 3, and the comparator 3 compares the counted number with the set number 5, but when the counted number 3 is less than the set number 5, the comparator 3 outputs a signal indicating that there is no ink remaining. is not output. Further, the counter 2 is reset when the detection signal output from the ink sensor 26 stops.

When the ink in the ink reservoir 23 decreases again due to printing and becomes less than a predetermined amount, the ink sensor 26 outputs a detection signal (t3 in FIG. 2), and the control device 1 outputs a pulse signal at predetermined intervals. The ink pump 27 is activated. At this time, if the ink container 28 is empty, no ink is supplied to the ink reservoir 23, so the ink sensor 26 continues to output a detection signal, and the control device 1 continues to output a pulse signal at predetermined intervals. Then counter 2 counts the number of pulse signals,
The comparator 3 compares the count number and the set number 5, and when the count number reaches 5 (second
At t4) in the figure, a signal indicating no remaining ink is output.
The operator is notified that there is no ink remaining in the ink container 28 by issuing a warning or display based on this ink empty signal.

Effects This invention is as described above, and when the amount of ink in the ink reservoir becomes below the lower limit, the control device inputs the detection signal output from the ink sensor and outputs a pulse signal at predetermined intervals, The ink pump operates every time this pulse signal is input, and when the detection signal and pulse signal are input at the same time, the counter counts the number of pulses of the pulse signal and inputs the count number to the comparator. The number of operations of the ink pump preset in the comparator is compared, and when the counted number exceeds the set number of operations, the comparator outputs a signal indicating that there is no remaining amount and causes the display means to display it. At the same time, since the input of pulse signals to the ink pump is stopped and the ink pump does not operate within a preset period of time, the viscosity of the ink changes with temperature changes, causing Even if the resistance changes and the number of operations of the ink pump per unit time varies, or the pulse signal is generated in synchronization with the rotation of the plate cylinder,
Even if the rotational speed of the plate cylinder changes and the pulse period changes, the ink pump operates only a preset number of times, so the amount of ink supplied is always constant and the amount of ink remaining in the ink container remains constant. This has the effect of being able to accurately detect.

[Brief explanation of drawings]

FIG. 1 is a control block diagram of the embodiment, FIG. 2 is a time chart of FIG. 1, and FIGS. 3 and 4 are explanatory diagrams of a conventional ink remaining amount detection device. DESCRIPTION OF SYMBOLS 1... Control device, 2... Counter, 3... Comparative product, 21... Ink supply roller, 22... Doctor roller, 23... Ink reservoir, 26... Ink sensor.

Claims (1)

[Scope of utility model registration request] An ink sensor that detects when the amount of ink in the ink reservoir formed by the ink supply roller and doctor roller falls below a predetermined lower limit value and outputs a detection signal, and stops outputting when it exceeds a predetermined upper limit value. , a control device of a stencil printing machine which inputs the detection signal and outputs a pulse signal at predetermined intervals during the input period; and a control device of a stencil printing machine which operates every time the pulse signal is inputted from the control device to remove ink from an ink container. The ink pump that supplies the ink reservoir, the detection signal and the pulse signal can be input at the same time, and the number of pulses is counted while the pulse signal is being input, and when the detection signal stops, , a counter that resets the count contents, and when the ink amount becomes below the lower limit value, it should be activated from when the detection signal is output until the ink amount reaches the upper limit value and the output stops. The number of operations of the ink pump is set in advance, and the count number counted by the counter is compared with the preset number of operations of the ink pump, and the count number is equal to or greater than the preset number of operations. The control device comprises: a comparator that outputs a no-remaining signal indicating that there is no ink remaining in the ink container; and means for inputting the no-remaining signal output from the comparator to issue an alarm or display; An ink remaining amount detection device for an ink container that stops inputting pulses to an ink pump when the no remaining amount signal output from the comparator is input.