RU1784684C - Method of controlling weft filament on loom with grip shuttle and device therefor - Google Patents

Abstract

SUMMARY OF THE INVENTION: the method comprises generating signals about the movement of the thread, generating gate pulses and detecting a break in the thread by the absence of a signal about the movement of the thread during the operation of the first gate signal. The value of the signal about the movement of the thread in the second section is accumulated during the time of rotation of the main shaft of the loom by an angle of 310-360 °, and the breakage of the thread is additionally determined in the second section with the value of the level of the accumulated signal about the movement of the thread below the threshold value at the moment the second gating pulse. 2 s.p. f-ly, 2 ill.

Description

Ј

The invention relates to weaving machinery and can be used to control the integrity of the weft weaving laid on weaving shuttle looms.

Known methods for controlling the weft yarn on a weaving shuttle loom and device for its implementation.

The disadvantages of this method and device is that in the area when the shuttle-grip starts moving backward from under the brakes (section II) due to uneven movement of the thread through the eye in the weft sensor, the signal from this sensor is unstable, there are dips in the signal; the boundary of the beginning of the signal is undefined. The probe (clock) pulse in duration is commensurate with the duration of the entire control section and is set so that it is only in

the boundaries of the site control. This leads to a large number of false shutdowns of the machine, reducing the productivity of the equipment.

A known method and device for controlling the weft yarn on a loom with a hook shuttle. By technical nature, this method is closer to the claimed one, it is selected as a prototype.

In the known method, the integrity control of the weft yarn is carried out at two characteristic sites. At the moment the weft thread begins to move (I section), a clock pulse is generated with a duration equal to the time the weft thread was laid over the entire width of the machine, then during the return of the hook-hook to the receiving device (I-th section), an additional clock pulse is generated at the time of approach left-handed weft yarn-VI

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l, its duration does not exceed the turning time of the main shaft of the machine by 1 °. Thread breakage is determined by the absence of a thread movement signal during the presence of clock pulses.

The weft control device on a weaving loom with a shuttle-gripping device comprises a weft sensor, in which, as a conversion of mechanical movement

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the strands into the electrical signal were used with piezers. T1lastINK, MOMENT control dial, band amplifier limiter, signal converter, probing pulse shaper, two-input logic circuit, stop unit, weaving machine stop unit and power unit.

The described method and device do not exclude false stops during operation of the machine in the second section. This is explained as follows.

The second section of work is when the shuttle hook returns to the receiver, i.e. begins to move backward from under the brakes, while part of the weft thread is brought into the throat. The compensator selects the length of the thread longer than it is freed. The difference is compensated by winding the yarn from the package. This movement is the source of the thread integrity signal. Since the laying conditions each time (length of the compensated filament, stopping distance of the plotter, asynchronous movement of the shuttle and the compensator) change, the signal from the sensor in this section is unstable, and this signal fails.

When using the known method, despite the fact that the clock pulse of the second section is of short duration, it is possible that it coincides with this dip, which will indicate the absence of this moment of the thread movement signal, i.e. break, which means that a signal is generated to stop the machine.

In addition, skipping of a thread break is possible due to the presence of a random signal from the weft sensor, due to small movements of the weft and due to vibration of the machine.

The purpose of the invention is to increase the reliability of registration of thread breaks and weft losses, eliminating false machine stops during control at the return area of the shuttle-grip

The goal in the method is achieved due to the fact that in the known method, which consists in generating a signal about the movement of the thread from the start of movement of the hook-grip to its entry into the braking device (1st section) and in the area of return of the hook-grip to the position releasing the weft thread and

transmitting it to the yarn feeder (11th section), form the first clock pulse with a duration equal to the time of weaving the weft thread over the entire width of the machine,

5 then, during the return of the shuttle-capture, an additional clock pulse of the second zone is formed with a pulse duration not exceeding the turn time of the main shaft of the machine by 1 °, the break of the thread is determined by the absence of a signal about the movement of the thread during the presence of the first clock pulse, the signal about the movement of the thread in the second section accumulate in the range from 310 ° to 360 ° rotation angle of the main shaft

5 of the machine, when the level of the accumulated signal is below the threshold value at the moment of the action of the strobe pulse of the second section, the breakage of the thread is determined. The goal in the device is achieved by

0 that in a known device for controlling the weft yarn containing a serial but connected weft sensor, a band-pass filter, a logic signal conditioner and the first logic circuit I, the sensor

5 angles connected to the second input of the first logical circuit AND through the first zone gating pulse shaper, second zone gating pulse shaper and stop unit, a control pulse shaper, OR circuit, integrator, comparator, second and third third of the AND circuit, and an inverter are introduced.

Comparison of the claimed solutions with other technical solutions in this area shows that the distinctive features give the method and device a new property: due to the formation of a strobe pulse of the second section, the accumulation of the signal about the movement of the thread on

In the second section and comparing the level of the accumulated signal with the threshold at the time of the gate pulse of the second section, it became possible to determine the section with the smallest dips, which improves the reliability of registration of thread breaks and weft loss, which means eliminating false stops of the machine when monitoring the thread in the section return shuttle capture. In FIG. 1 shows the functional

0 diagram of the proposed device that implements the proposed method; in FIG. 2 shows voltage plots in a circuit.

A device for controlling the weft yarn on a loom with a grip shuttle co5 holds a weft sensor 1, an angle sensor 2, a band-pass filter 3, a logic signal driver 4, a gate 1 pulse generator 5, a first logic circuit I, a stop unit 7, a driver 8

control pulse shaper 9

the gate pulse of section II, the OR circuit 10, the integrator 11, the threshold signal conditioner 12, the comparator 13, the second I circuit 14, the third I circuit 15, the inverter 16.

In FIG. 2 marked: 4 - signal at the output of the shaper 4 of the logical signal; 5 - signal at the output of the driver 5 of the gate pulse of the I zone; 8 - signal at the output of the 8 pulse shaper; 9 - signal at the output of the driver 9 of the gate pulse of the II zone; 13 - signal at the output of comparator 13; 15 - signal at the output of the third circuit I.

The magnitude of the circuit elements is calculated from the condition that there are no false stops in the presence of dips in the signal of the weft sensor due to irregular movement of the thread. All devices are made on microchips of the type КР 1561 ТЛ 1.

The sensors used are the same as in the prototype.

Moving with the thread, acting on the sensitive element of the weft sensor 1, creates an electric signal that is variable in amplitude and frequency. This signal, amplified and filtered out from interference and limited by a band-pass filter 3, is supplied to driver 4, which turns it into a signal of a certain logical level 4. This signal is stable in the first section of the machine, and there are dips in the signal in the second section it is fed to one of the inputs of the logic circuit b I.

The angle sensor at the moment of rotation of the main shaft by an angle of 240 ° generates a pulse that starts the driver 5 of the gate pulse 1 of the section. The end of the gate pulse is determined by the arrival time of the duck weaver.

If the thread during operation in the area from the start of the shuttle-grip movement to its entry into the braking device (section I) is intact, the shaper 4 generates an O signal level that does not change the state of the first circuit 6 AND, therefore, the state of the second circuit does not change 14 And, and therefore, a signal to stop the machine at the output of block 7 will not be generated. When the thread breaks in 1 operation section, a signal equal to 1 is generated at the input of the shaper 4. Due to this, the state of circuit 6 changes and a signal is generated at the output of block 7 to stop the machine.

At the moment of the beginning of the reverse movement of the shuttle (this moment 310, a pulse is generated by which the zero-level control pulse shaper 8 is launched, which arrives at one of the inputs of the circuit 10

OR. The duration of this pulse is adjustable from 3-5 m / s to a value corresponding to the end of the reverse movement of the hook-grip, but no later than 360 ° of the rotation angle 5 of the main shaft of the machine 8. A trailing pulse generator 9 of the second section is triggered by the trailing edge of this pulse.

Gating Pulse Duration

Section II 0 is not so critical for the claimed method as it is for the method selected for the prototype (ed. St. No. 950822). In the inventive method, it is possible to form the duration of the construction pulse of section II equal to the time of return of the shuttle-capture to the receiving device. For better controller operation, the gate pulse of section II was selected with a duration not exceeding the time of turning the main shaft of the machine by 1 °. as in the prototype.

The second input of the OR circuit 10 is connected to the logic driver 4. With a whole weft thread at the input of circuit 10

5 OR there is a positive signal supplied to the integrator circuit 11, the voltage at which reaches the value specified by the threshold circuit 12 in 0.5-1 ms and is established at the output of the comparator 13

0 the value of the voltage corresponding to logical O. The dips in the sensor signal are filtered by the integrator, without changing the state of the comparator 13. If by the time the pulse ends

5 of the shaper 8 and, therefore, the gating pulse of the shaper 9 did not break the thread, then the output state of the third circuit 15 AND does not change and the pulse to the stop unit does not

0 will pass. If the thread is broken, the voltage at the output of the integrator 11 by the time the pulse ends, the control of the driver 8 will be lower than the threshold specified by the circuit 12, and a signal 5 will be established at the output of the comparator. equal to logical G, therefore, after a gating pulse arrives from the driver 9, the state at the output of the third circuit 15 And changes, which will lead to the output through the inverter 16 and the second circuit

0 14 And commands to the stop block.

The presence of a random signal at the output of the driver 4 does not provide the accumulation of the signal at the input of the comparator is greater than the value of the threshold voltage 12, which does not

5 will change the state of the comparator, which means that a stop signal will be generated.

Thus, we believe that in the proposed method for determining the breakage of the weft yarn, a signal is generated about the movement of the yarn in the I section and in the II section,

the gate pulses of the first section, the gate pulse of the second section are formed at the end of the reverse movement of the shuttle-grip, but not later than 360 ° of the rotation angle of the main shaft of the machine, and the signal about the movement of the thread in the second section for a time from 310 ° to 360 ° of the rotation angle of the main the machine shaft is accumulated and compared with a threshold value at the time of the action of the gate pulse of section II, which ensures the absence of false machine stops in the presence of dips in the duck sensor signal. This is achieved by incorporating a control pulse generator, a second and third AND circuit, an OR circuit, an integrator, a comparator, a threshold level generator and an inverter into the device.

The proposed method and device allow recording all losses of the weft both when it is laid and in the return area of the shuttle-grip from under the brake, which improves the quality of the fabric produced and completely eliminates the rejection of the canvas by the weft.

Elimination of false stops reduces equipment downtime, increases fabric production per weaver.

Claims (2)

1. A method of controlling the weft yarn on a weaving machine with a hook-grip, which generates a signal about the movement of the weft yarn in the first section - from the start of the shuttle-grip movement to its entry into the braking mechanism and in the second section - return of the hook-grip to the release position weft yarn and transferring it to the yarn guide. at the moment the weft thread begins to move, a strobe pulse of the first section is formed with a duration equal to the time the weft thread was laid over the entire width of the machine, then, during the return of the hook-shuttle, a strobe pulse of the second section with a duration not exceeding the turning time of the main shaft of the machine by 1 ° is formed; and the breakage of the thread in the first section is determined by the absence of a signal about the movement of the thread during the presence of the first gating pulse, and so on, so that, in order to increase the reliability of recording breaks iti and losses weft signal value of the movement of the thread in the second section is accumulated during the rotation time of the main shaft of the loom by an angle of 310-360 °, and the breakage of the thread is additionally determined in the second section when the level of the accumulative signal about the movement of the thread is lower than the threshold value at the time of the second gating pulse. 2. A weft control device on a weaving loom with a shuttle-grip, comprising a weft sensor, a band-pass filter and a logic driver, connected in series to the rotation angle sensor of the main shaft of the weaving machine and a pulse former of the first section, as well as a gate generator of the second section, the first AND circuit and a stop unit, characterized in that, in order to increase the reliability of recording of wire breaks and weft losses, it is equipped with an OR element connected in series, an integrator and a comparator, a control driver momentum, second and third elements and the inverter and the shaper of the threshold signal connected to the second input of the comparator, while the output of the shaper of the logical signal through the first and second elements And is connected to the stop unit of the machine and directly to the first input of the OR element, the second input of which is connected through the driver of the control pulse to the angle sensor and combined with the input of the driver of the strobe pulse of the second section, the output connected to the first input of the third element And, the second input of which is connected to the output of the comparator , and the output through the inverter with the second input of the second element And, and the output of the driver of the gating pulse of the first section is connected to the second input of the first Element I. Rchg. i