JPH0342472A - Open-circuit detecting circuit for wire drawing machine line - Google Patents

Abstract

PURPOSE:To detect the open circuit or the danger of the open circuit of a wire rod quickly and surely from the position of a dancer roll by utilizing the output signal of a position transmitting means for adjusting the dancer roll position, and detecting the dancer roll action limit position or a position immediately before the limit position with a comparator. CONSTITUTION:When a dancer roll 30 is located at the center position, the output of an adder 42 is zero, a signal with the positive polarity is outputted when it is on the upper limit side, and a signal with the negative polarity is outputted when it is located on the lower limit side. When an absolute value circuit 43 feeds the absolute value of the output of the adder 42 to the first and second comparators 45 and 48, the comparator 45 detects that the dancer roll 30 is moved to the action limit position. When the output from the absolute value circuit 43 reaches the preset value of an action limit setter 44, it is judged that a wire rod 2 has an open circuit, a signal is fed to the first relay 46, and a wire drawing machine line is stopped. The comparator 48 is operated immediately before the dancer roll 30 reaches the action limit position, when the wire rod 2 is extended, a relay 49 receives a signal from the comparator 48 and generates a warning.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a circuit that detects wire breakage using a position transmitter output signal from a dancer roll that absorbs speed differences between wire drawing machines.

[Conventional technology]

FIG. 2 is a control block diagram showing a conventional example of control of a wire drawing machine line equipped with dancer rolls.

In FIG. 2, the wire rod 2 running in the direction of the arrow from left to right is drawn by the first wire drawing 8110, which is composed of a die 11, a drum 12, an electric motor 13, and a speed transmitter 14, and then drawn by the die. 21, drum 22, electric 1123
and a speed transmitter 24.
In order to absorb the difference in the wire running speed between the first wire drawing machine 10 and the second wire drawing machine 20, a dancer roll 30 is installed between the first wire drawing machine 10 and the second wire drawing machine 20. It is installed.

For example, if the wire running speed of the first wire drawing machine 10 is faster than the wire running speed of the second wire drawing machine 20,
Since the amount of wire rod 2 retained between both wire drawing machines increases, the dancer roll 30 moves downward to store the increased amount of wire rod.

If the speed of the first wire drawing machine 10 is slower, the dancer roll 30 will move upward and release the stored wire.

The dancer roll 30 is connected to a position transmitter 31 (for example, a celsin transmitter) for detecting its position, and the position detection signal outputted by the position transmitter 31 is made positive with a diode 32. The signal is input to the position adjuster 34, which is composed of a proportional-integral calculator. One position setting device 33
In this case, the predetermined position of the dancer roll 30 is set using a negative polarity signal, and the position adjuster 34 is manually operated. This position adjuster 34! I! The one-section operation outputs a control signal to the adder 16 such that the position detection signal matches the position setting signal.

The first wire drawing machine 10 and the second wire drawing machine 20 adjust their speed to the speed setting value obtained from the speed setting n3 through the acceleration/deceleration calculation n4 by the action of the respective speed control devices 15 and 25. controlled to do so.

(However, the cross-sectional area of the wire rod 2 after passing through the die 11 is different from the cross-sectional area of the wire rod 2 after passing through the die 21, so in reality, the ratio setting device to cover this area reduction rate is
Although it is inserted into the speed setting signal line to tilO, illustration thereof is omitted. ) The control signal output by the position adjuster 34 has different polarity depending on whether the dancer roll 30 is above or below a predetermined position. Therefore, the speed setting signal from the adder 16 to the speed control device 15 increases or decreases. That is, the first wire drawing machine 10 changes its speed in response to the positional fluctuation of the dancer roll 30, and always maintains the dancer roll 3.
It is controlled so that 0 is at a predetermined position.

[Problem to be solved by the invention]

By the way, if some abnormality occurs in the wire drawing machine line that is being operated as described above, such as a breakage of the wire rod 2, the position of the dancer roll 3o moves to the operating limit point.

A limit switch is usually installed at this operating limit point, and when the ξat switch is operated, it is determined that a wire breakage has occurred and the wire drawing machine line is suddenly stopped. However, after a wire breakage occurs and the wire is suddenly stopped, the wire drawing machine line must be cleaned up before the wire drawing machine line can be restarted, resulting in a large loss of tR, such as a great deal of effort and time and the disposal of wire rods.

Therefore, in order to detect a wire breakage accident in advance, it is conceivable to use another limit switch to detect that the dancer roll 30 has moved to a dangerous position before reaching the operating limit point.

However, due to the mechanism of the dancer roll, it is difficult to install the limit switch in a position where maintenance and inspection is easy.Moreover, the operating position of the limit switch must be delicately adjusted, making maintenance and inspection difficult. Not only that, but it also has major problems that reduce the reliability of the device.

SUMMARY OF THE INVENTION An object of the present invention is to quickly and reliably detect wire breakage or the risk of wire breakage from the position of the dancer roll without relying on limit switches.

[Means to solve the problem]

In order to achieve the above object, the wire breakage detection circuit of the present invention comprises a first wire drawing machine and a second wire drawing machine each separately equipped with a speed control means.
A wire drawing machine consisting of a wire drawing machine and a dancer roll located between the two machines and equipped with position transmitting means to adjust its position in order to absorb the speed difference between the wire passing through the two machines. In the machine line, an absolute value circuit for determining the absolute value of the position transmitting means output signal of the dancer roll, a first comparator for detecting the operating limit position of the dancer roll from the absolute value signal, and a first comparator for detecting the operation limit position of the dancer roll from the absolute value signal; and a second comparator that detects when a predetermined value approaches the operating limit position.

[Effect]

This invention attempts to use the output signal of a position transmitting means used to control the dancer roll to a predetermined position in place of a switch, and can be used for both the upper limit side and the lower limit side. After converting the output signal of the position transmitting means into an absolute value, a comparator is used to arbitrarily set the operation limit position of the dancer roll, or a position slightly before this.

〔Example〕

FIG. 1 is a block diagram showing an embodiment of the present invention.

This FIG. 1 shows a circuit added to the illustrated position transmitter 31 in addition to the conventional circuit already described in FIG.

Therefore, illustration of the wire drawing machine line portion already described in FIG. 2 is omitted.

In FIG. 1, a sershin oscillator 31 as a position transmitting means for outputting a position signal of a dancer roll 30 rectifies its output with a diode 32, and then divides the output into an appropriate signal level with a signal level setter 41.

The position setting device 33 sets a predetermined value W(-a
This is to set the center position between the upper and lower limits of the movement), and the signal divided by the signal level setter 41 is set to zero at the lower limit position of the dancer roll 30, and at the upper limit position. If you want to output +10 volts, set this position setting device to output 15 volts. Therefore, the position adjuster 34, which is composed of a proportional-integral calculator, receives the position signal input via the signal level setter 41,
The setting signal from the position setting device 33 is input, and a control signal that makes the re-input deviation zero is output to the speed control device of the wire drawing machine, but this part is outside the scope of the present invention and will not be explained. is omitted.

In the present invention, the output of the signal level setter 41 and the output of the position setter 33 are added in the adder 42, so if these outputs are set to the above-mentioned values, the dancer roll is at a predetermined position. That is, when it is at the center position, the output of the adder 42 is zero, when it is on the upper limit side of the center position, a positive polarity signal is output, and when it is on the lower limit side of the center position, a negative polarity signal is output. Ru.

After converting the output of the adder 42 into an absolute value, the absolute value circuit 43 supplies this signal to the first comparator 45 and the second comparator 48 .

The first comparator 45 is for detecting that the dancer roll 30 has moved to the operating limit position, and the detected position is set by the operating limit setting device 44, and the output from the absolute value circuit 43 is When the set value of the operation limit setter 44 is reached, it is determined that the wire 2 is broken, and a signal is sent to the first relay 46 to stop the wire drawing machine line.

The second comparator 48 adjusts the limit approach position setter 47 so that the dancer roll 30 operates just before it reaches its operating limit position. The second relay 49 receives the signal from the second comparator 48 and issues an alarm, and when the dancer roll 30 reaches its limit position due to wire breakage, the wire drawing machine line is stopped.

[Effects of the Invention] According to the present invention, the comparator detects the dancer roll operating limit position or a point slightly before the operating limit position by using the output signal of the position transmitting means for adjusting the dancer roll position. This makes it much easier to set and adjust the position compared to conventional limit switch methods, and it not only detects wire breakage, but also detects the danger of wire breakage in advance. This can be done with precision and greatly improves the reliability of device protection.

[Brief explanation of drawings]

Figure 1 is a block diagram showing an embodiment of the present invention, Figure 2 is a block diagram showing an embodiment of the present invention.
The figure is a control block diagram showing a conventional example of control of a wire drawing machine line equipped with dancer rolls.

Claims (1)

[Claims] 1) A first wire drawing machine and a second wire drawing machine each having separate speed control means.
A wire drawing machine consisting of a wire drawing machine and a dancer roll located between the two machines and equipped with position transmitting means to adjust its position in order to absorb the speed difference between the wire passing through the two machines. In the machine line, an absolute value circuit for determining the absolute value of the position transmitting means output signal of the dancer roll, a first comparator for detecting the operating limit position of the dancer roll from the absolute value signal, and a first comparator for detecting the operating limit position of the dancer roll from the absolute value signal; A wire breakage detection circuit for a wire drawing machine line, comprising a second comparator that detects when the position approaches a predetermined value.