JPS62226013A - Photoelectric detecting device - Google Patents

Abstract

PURPOSE:To detect a partial end breakage at the time when an end breakage has been generated partially, by generating a reference signal which is delayed by a prescribed time and follows a detecting signal being proportional to a light quantity variation of a light beam caused by an object, and calculating a difference between said signal and the detecting signal. CONSTITUTION:In a thread working equipment for yarn doubling, a detecting device 100 is provided on the upper part of a winding part, and monitors an end breakage. In this device 100, as a light beam L from a light emitting circuit 101 is photodetected by a photodetecting circuit 102, and cut off periodically by a yarn Y for ballooning, therefore, a pulsative detecting signal is outputted from the circuit 102. This signal is amplified 103 and inputted to an inversion input terminal of an arithmetic circuit 105 consisting of a differential amplifier through an integration circuit 104. Also, to a non-inversion input terminal of the circuit 105, a reference signal which follows the detecting signal, and has been delayed by a delaying circuit 106 is applied, so that a voltage is not generated in the circuit 105 at the normal time. In this state, if one piece of doubling yarns is broken, the detecting signal drops, the circuit 105 generates an arithmetic output signal, and this signal becomes an end breakage signal and the end breakage processing is executed.

Description

Detailed Description of the Invention [Field of Application] The present invention relates to a photoelectric detection device capable of determining the size of an object, and particularly to a photoelectric detection device capable of determining the size of an object. The present invention relates to a photoelectric detection device suitable for detecting yarn breakage, etc.

[Prior art] A photoelectric detection device for detecting yarn breakage, etc.
There is a transmission type photoelectric detection device that utilizes periodic optical axis interruption by a thread to be photographed, which is disclosed in Japanese Patent No. 31099 and the like. In processing equipment such as drawing and twisting machines and false twisting machines, a photoelectric detector for detecting yarn breakage is installed upstream of the winding section and a photoelectric detector is installed upstream of the processing section, as disclosed in Japanese Utility Model Application Publication No. 48-2911. The yarn breakage process is generally carried out by a yarn breakage processing device comprising a yarn processing device such as a cutter that is operated by a yarn breakage signal from a photoelectric detector installed at the end of the yarn.

However, in gold thread processing equipment that processes multiple threads by piling them together, even if one of the threads is broken, the remaining threads continue to periodically interrupt the optical axis. Even if a breakage occurs in one part of the yarn, it cannot be detected and winding continues, resulting in the production of a defective yarn.

[Object of the Invention] The present invention aims to provide a photoelectric detection device that does not have the above-mentioned problems, and therefore, it is an object of the present invention to provide a photoelectric detection device that can be applied to detect partial yarn breakage when yarn breakage occurs in one part of a plurality of yarns. The purpose is to

[Structure and operation of the invention] The above objects are achieved by the invention as follows.

That is, the present invention includes a light emitting section that emits a light beam, a light emitting section that receives the light beam that is blocked or reflected by an object,
In a photoelectric detection device equipped with a photoelectric conversion unit that outputs a detection signal proportional to a change in the light intensity of a light beam caused by an object,
A photoelectric detection device characterized by comprising a delay circuit that generates a reference signal that follows the detection signal with a certain time delay, and an arithmetic circuit that calculates the difference between the reference signal and the detection signal.

The present invention described in (e) above was made as follows. That is, in the above-mentioned white yarn equipment, one of the doubling yarns
When the part breaks, the outer diameter of the doubling yarn that blocks the optical axis becomes smaller. For this reason, the amount of transmitted light of the charge detection device is larger than that before one part of the yarn is broken. Therefore, if the vibration speed of the yarn is constant, the level of the pulse signal generated by the optical axis interruption due to the vibration of the yarn decreases approximately in proportion to the outer diameter of the doubling yarn. Since the shooting speed of the yarn is approximately constant, one possible method is to use changes in this signal level to compare it with a reference value and find out that part of the doubling yarn has broken, but this method has the disadvantages described below. be. As mentioned earlier, when the outer diameter of the yarn changes, the detection signal level also changes. This means that when the denier of processed yarn is changed, the standard value must also be changed. In addition, in the case of a winding device on a processing beach, etc., the traverse speed is oscillated within a certain range in order to maintain the yarn package well, and in the case of winding with a draw twister, etc., the spindle rotation speed is changed for the same purpose. Since program-controlled winding is performed with the aim of gradually changing the winding and maintaining good winding, the vibration speed of the yarn also changes gradually, and is not constant over a long period of time, and the signal level changes. Furthermore, the parts constituting the photoelectric detection device, the dirt between the emitting and receiving light, the environment, etc. are not always constant, and the signal level changes. There are many factors that cause the signal level to change as described above, and there is a problem in that stable detection cannot be achieved by comparison using a constant reference value.

As a result of considering various solutions to this problem, we found that although the above-mentioned change factors are relatively long-period, the signal changes associated with thread breakage occur in a short time, and we automatically corrected the long-period changes. The present invention has been conceived to allow only short-term changes to be detected effectively and stably. That is, in the present invention, the signal level of a predetermined time ago, specifically, several seconds ago, is always stored and that value is used as a reference value, so that the reference value automatically follows long-period fluctuations. By comparing this reference value with the current signal level, it is possible to detect short-term changes such as the aforementioned thread breakage, and therefore detect artificial changes such as the aforementioned change in denier and changes in the emitter and receiver. A photoelectric detection device that can respond to long-term fluctuations such as environmental changes and signal changes accompanying program winding is realized.

Therefore, when applied to detecting yarn breakage in one part of the doubling yarn,
The detection signal level at the time of thread breakage changes in an extremely short time.

If this detection signal that changes at high speed and a reference signal that responds to this detection signal with a delay of a certain time constant are inputted into a differential amplifier or the like and compared, a pulse-like interruption with a time width due to the delay of the time constant is generated. Specifically, the yarn signal is a pulsed yarn breakage signal 19 associated with the voltage difference between the detection signal and the reference signal. In this configuration, changes in process conditions, such as denier changes, program changes, and other disturbance factors, are automatically compensated as a reference signal, so that part of the yarn can be stably and sensitively detected without being affected by these changes. This allows thread breaks to be detected.

The details of the present invention will be explained below with reference to the drawings based on an example in which the present invention is applied to yarn breakage detection in yarn processing equipment.

FIG. 1 is an explanatory diagram of yarn processing equipment according to an embodiment.

FIG. 2 is a block diagram of the embodiment, and FIG. 3 is an explanatory diagram showing waveforms of signals at each point in FIG.

FIG. 1 is an example of yarn processing equipment for doubling two yarns.

The yarn (Y) is a creel (not shown) yarn package (
The yarn is set from P) to the cutter (C) and fed by the yarn feeding roller (FR), heat set by the heater (l), stretched by the drawing roller (DR), and wound up by the winding section (W>, It is wound up into a pirn (P').

A photoelectric detection device 100 of the present invention housed in a U-shaped case is provided above the winding section (W) to monitor yarn breakage. If a problem occurs in which one or two of the yarns (Y) are broken and wound around the yarn feeding roller (FR) or drawing roller (DR), the photoelectric detection device 100 detects this by the operation described below. , both cutters (C) are driven by the yarn breakage signal, and feeding of the two yarns (Y) is stopped.
It is configured to wait for thread breakage processing.

The photoelectric detection device 100 described above is configured as shown in FIG. A light beam L from a light emitting circuit 101 using an LED or the like is received by a light receiving circuit 102 using a photodiode or the like. Since this light beam L is periodically interrupted by the ballooning yarn Y, the light receiving circuit 102 outputs a pulsed detection signal. This signal is amplified by the AC amplifier circuit 103 to obtain the detection pulse signal shown in FIG. 3(1). Next, the signal is converted into analog by the integrating circuit 104, and the detection signal 2 shown in FIG. 3(2) is obtained. This detected voltage signal (2) is input to an inverting input terminal of an arithmetic circuit 105 consisting of a differential amplifier. To the non-inverting input terminal of the arithmetic circuit 105, the reference signal ◎ shown in FIG. Arithmetic circuit and delay circuit 1
06 used an integrating circuit with a predetermined time constant.

Now, when one of the doubling yarns breaks, the level of the detection pulse signal (■) and the inner part are reduced by almost half, the detection voltage signal (■) decreases in a stepwise manner, and the arithmetic circuit 105 operates as shown in FIG. ) generates a calculation output signal O. The calculated output signal (2) is converted into a thread break signal @[F] of a constant pulse by a waveform shaping circuit 107 such as a monomulti circuit. By using this thread breakage signal [F] as a cutter operation signal, the above-mentioned thread breakage process is performed. The generated arithmetic output signal O is eventually delayed by the delay circuit 106 and applied to the non-inverting input of the arithmetic circuit 105, so that it balances out and stabilizes at a low voltage.

With the above configuration, 1li1-period fluctuations longer than the period determined by the time constant of the delay circuit 106 are always erased, and the calculated output signal ■ differs depending on the underground ratio of the delay circuit 106 under normal conditions, but is extremely low at several tens of yrt V or less. It balances out at a voltage close to zero and is stable.

Although the present invention has been described above using examples, the present invention is not limited to these examples.

We have shown a system in which a delay circuit is used as a feedback loop for an arithmetic circuit that has high stability and detection sensitivity during normal operation.
A configuration in which a delay circuit 106 that directly inputs the detected voltage signal ■ to the delay circuit 106 and inputs the output of the delay circuit 106 to one terminal of the arithmetic circuit 105 is provided in parallel with the connection line between the integrating circuit 104 and the arithmetic circuit 105 may also be used. This advantage is clear from the spirit of the present invention.

Furthermore, it goes without saying that other known configurations may be used for the configurations of the individual circuits.

It is clear from the structure that the present invention described above can be applied to a wide range of fields other than partial yarn breakage, such as determining the size of objects and edges.

Furthermore, the present invention can be applied to any type of photoelectric detector, regardless of whether it is a transmissive type or a reflective type, as long as it can finally obtain a detection signal proportional to the change in light δ caused by the object in the light beam from the light emitting part. It is clear from the spirit of the present invention that the present invention can be applied regardless of the lighting method. The shape of the photoelectric detection device is also U as in the example.
The f13. It goes without saying that it is also fine to be similar.

As described above, the present invention is very useful in imparting new functions to a photoelectric detection device and expanding its field of application.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of a yarn processing machine according to an embodiment. FIG. 2 is a block diagram of the embodiment, and FIG. 3 is an explanatory diagram of signal waveforms of each part thereof. 100: Photoelectric detection device 101: Light emitting circuit 102: Light receiving circuit 105: Arithmetic circuit 106: Delay circuit Fig. 1

Claims (1)

[Claims] 1. A light emitting unit that emits a light beam, and a photoelectric conversion unit that receives the light beam blocked or reflected by an object and outputs a detection signal proportional to a change in the amount of light of the light beam caused by the object. The photoelectric detection device is characterized by comprising a delay circuit that generates a reference signal that follows the detection signal with a certain time delay, and an arithmetic circuit that calculates the difference between the reference signal and the detection signal. Photoelectric detection device. 2. The photoelectric detection device according to claim 1, wherein the delay circuit is an integration circuit with a predetermined time constant, and the arithmetic operation circuit is a differential amplification circuit. 3. The photoelectric detection device according to claim 1 or 2, wherein the delay circuit forms a feedback loop with respect to the arithmetic circuit. 4. A light beam is intermittently blocked or reflected by an object, and the photoelectric exchange unit includes a light receiving element that converts the blocked or reflected light beam into an electrical signal, and an AC amplifier that amplifies the output of the light receiving element; A photoelectric detection device according to any one of claims 1 to 3, comprising a conversion circuit that converts a pulse output of an AC amplifier into an analog signal. 5. The photoelectric detection device according to any one of claims 1 to 4, wherein the object is a spliced yarn in which a plurality of yarns are spliced.