SU1377308A1 - Method and apparatus for monitoring loom operation - Google Patents

Abstract

This invention relates to a textile industry. The purpose of the invention is to improve the quality of the fabric; by reducing the likelihood of occurrence; there are no invalid defects in it. The signals from the outputs of sensor 1 and setpoint 3 of the defective fabric are fed to the inputs of discriminator 2. If the specified (acceptable) defect of the fabric is lower than the actual, the discriminator 2 switches trigger 4, which permits the passage of each signal about underflow or breakage threads from the sensor 12 to the mechanism 13 stop the loom. If a given fabric defectiveness is higher than the actual one, then the weaving of the weaving machine after each woven thread (undershoot) of the weft yarn does not occur until the fabric produced has a defectiveness lower than the allowable one. 2 sec. f-ly, 1 ill. (L

Description

The invention relates to the textile industry.

The purpose of the invention is to improve the quality of the fabric by reducing the likelihood of unacceptable defects in it.

The drawing shows a block diagram of a device explaining the essence of the method.

The device comprises a sensor 1 for the defectiveness of the produced tissue, the output of which is connected to the first input of the discriminator 2. At the second input of the discriminator 2, the output of the master 3 of the defectiveness of the produced tissue is connected. Two pulse (discrete) outputs of discriminator 2 are connected to the corresponding mutually inverse inputs of trigger 4. A potential (analog) output of discriminator 2 is connected to the input of amplifier 5. The output of amplifier 6 is connected to the input of amplifier 5. The output of the amplifier 5 is connected to the input of an analog-to-digital converter (ADC) 7, the output of which is connected to an adjustable frequency divider 8. Another input of the frequency divider 8 is connected to the output of the counter 9 of the number of weft threads through element And 10. One input of the control unit 11 is connected to the output of the frequency divider 8, the other to the sensor 12 of the underflow and break of the weft, and the third to the weaving stop mechanism 13 machine tool. The control unit 11 has three outputs connected to the inputs of the frequency divider 8, element AND 10 and element OR 14, respectively. The output of the sensor 12 is connected to the corresponding input of the logical element And 15. The other input of the element And 15 is connected to the output of the trigger 4. The output of the element And 15 is connected to the input of the element OR 14. Element OR 14 former (one-shot) 16 is connected to the mechanism 13.

The essence of the proposed method is to implement the following relationship

N Ξ Т ξ L = Kd, (1) where N is the number of specified scraps of the weft thread after the appearance of the first shortage or break of the weft thread}.

T is the control time specified after the appearance of the first under-flying (break) of the weft thread;

L is the control length of the tissue, specified after the appearance of the first · under-shortage or breakage of the thread;

K is the coefficient of proportionality;

d is the current value of the defectiveness of the produced tissue, for example, in points / meter.

A method of controlling the operation of a loom using the proposed device is as follows.

A signal about the current value of defectiveness from sensor 1 and a signal of a predetermined level (value) of tissue defectiveness20 from the setter 3 are fed to the inputs of discriminator 2. If the current value of defectiveness of the fabric is lower than the specified level of defectiveness, trigger 4 remains in its original position, 25 i.e. at its output, the signal corresponds to position 0 and, thus, element 15 blocks the passage of impulses of shortages and breaks of the thread from sensor 12 to element OR 14. The current value of the defect, simultaneously coming from sensor 1, is transmitted through discriminator 2 to the input of amplifier 5, the gain of which is set using the adjuster 6 gain coefficient 35, in accordance with the dependence (1). The amplified analog signal corresponding to the value of N, from the amplifier 5 is fed to the ADC 7, which converts the analog value of N into a digital code, i.e. the value of N is transferred to the control number of scraps of the weft thread. The signal in binary digital code from the ADC 7 is fed to the frequency divider 8, acting as a division coefficient. The control unit 11 prepares the element And 10 to pass the pulses of the counter 9 number of prokidok. From the element And 10 pulses arrive at delhi50 ted 8 frequency. At the output of the divider, the signal appears after a predetermined number of ducks. If shortages and breaks do not appear on a given number of duck prokidoks, from the output of divider 55, the signal enters control unit 11, which returns ^ divider 8 to its original position. If a predetermined number of duck prokidoks appears for a second shortage, then the signal from the control unit 11 through the OR element 14 is fed to the forma-. body 16. The pulse from the shaper 16 is supplied to the mechanism 13, which stops the machine.

From the output of the mechanism 13, the signal is supplied to the control unit 11, preparing a device for fixing subsequent shortages. The device is ready for the next cycle of work. Thus, if the current value of the defectiveness does not exceed the level set by the setter 3, the under-control device operates in the machine stop mode in the event of a second shortage within the specified after the first shortage the control number of weft scraps, the latter being directly proportional to the defectiveness of the produced fabric. The proportionality coefficient is equal to K, which is determined by the formula (1) and is set by the setter 6.

If the current value of the defectiveness is greater than the level set by the setter 3, the following occurs. From the pulse output of discriminator 2, the pulse arrives at the input of trigger 4 and switches it from its original position to another. At the output of trigger 4, a signal corresponding to 1 appears and prepares AND element 15 for passing signals from sensor 12 to OR element 14. The device operates in the machine stop mode due to each shortage. The signal from the output of the OR element 14 through the shaper 16 is fed to the mechanism 13, which stops the machine at each shortage. From the output of the mechanism 13, the signal enters the control unit 11, preparing the device for the subsequent start-up of the machine.

Claims (2)

Claim 1. The method of controlling the operation of the loom, which consists in verifying the correctness of the weft yarn, in continuously monitoring the defectiveness of the fabric being produced and in stopping the weaving machine when the actual defectiveness exceeds the permissible one, characterized in that, in order to improve the quality of the fabric by reducing the likelihood of of unacceptable defects, after the registration of the first incorrect laying of the weft thread, the control number of the weft thread throws is set, the value of which is determined by the actual defectiveness yrabatyvaemoy tissue and produce a machine stop when registering the second incorrectly routed weft yarn during the time the reference number of pads prokidok weft yarn. 2. A device for monitoring the operation of the loom, containing a defective sensor and an allowable setter: defectiveness of the fabric being produced, connected to the corresponding inputs of the discriminator, the analog output of which is connected to the information input of the amplifier, a counter of the number of drops of the weft thread, a sensor of underflow and breakage of the weft thread, a control unit and a stop mechanism of the loom, characterized in that, in order to improve the quality of the fabric by reducing the likelihood of unacceptable defects in it, it is equipped with an analog- a digital converter controlled by a frequency divider, AND elements, an OR element, a trigger and a gain setter, while the output of the gain setter is connected to the control input of the amplifier, the output of which is connected via an analog-digital converter to the control input of an adjustable frequency divider, a reset input connected to the first output control unit, information input - to the output of the first AND element, and output - to the first input of the control unit, the second and third inputs of which are connected to responsibly with the outputs of the sensor of shortage and breakage of the weft thread and the stop mechanism of the loom, and the second and third outputs of the control unit are connected respectively to the first inputs of the OR element and the first element And, the second input associated with the output of the counter of the number of scraps of the weft thread, and the discriminator discriminated outputs are connected to the corresponding mutually inverse inputs of the trigger, and the outputs of the trigger and the sensor of shortage and breakage of the weft thread through the second AND element are connected to the second input of the OR element, the output of which is connected with input 'of the stop mechanism of the loom.