SU757615A1 - Automatic weft stopper of shuttleless loom - Google Patents

Description

The invention relates to automatic devices for controlling the weft yarn and stopping the shuttleless loom in violation of the process of its laying.

A device for the automatic weaving stop of a weaving machine is known, which contains contact elements of the weft thread monitoring period connected to the control circuit of the weaving machine actuator

The disadvantage of this device is the low accuracy of the control of the start and end time of the weft thread and, accordingly, the poor quality of the device operation 15.

It is also known a device for automatic weaving stop of the shuttleless loom, comprising a sensor 20 for the start of the control interval with a permanent magnet placed on the flywheel of the main shaft of the machine and a sensor for the end of the control interval connected to the trigger trigger 25 sensor inputs, a thread consumption sensor connected to the first input of the comparison element, the second the input of which is connected with the output of the trigger shaper, and the output by means of expansion

2

pulse spreader - with an actuator [2].

A disadvantage of the known device is constructive complexity and low reliability.

The aim of the invention is to improve the reliability of the device.

This is achieved due to the fact that the device contains an additional permanent magnet placed on the flywheel of the main shaft of the machine with an offset along the circumference and height of the flywheel relative to the first magnet, and the sensitive elements of the sensors of the beginning and end of the control interval are in the form of reed switches placed on the machine bed opposite the flywheel in the area of the relevant magnets.

FIG. 1 shows a schematic representation of the proposed automatic weft stop device; FIG. 2 is a circuit diagram of the device) in FIG. 3 constructive implementation of sensors of the beginning and end of the control interval; in fig. 4 - timing diagram of the operation of the elements of the device.

The device contains a sensor 1 consumption of the thread, for example, contact ·

3

757615

four

A type that reacts to tension, is installed between the weft boby (Noah 2 and the brake 3 of the weft thread, as well as the sensor 4 at the start of the control interval and the sensor 5 at the end of the control interval, connected to the actuator control circuit 6 (not shown).

. Sensitive elements of the sensors are made in the form of magnetically controlled sealed contacts (reed switches) 7 and 8 installed on the stationary block of the machine brake mechanism using a bracket 9. A pair of permanent magnets 11 and 12 are mounted on the rim of the graduated scale of the flywheel 10 of the main shaft of the machine and can affect the corresponding magnetically controlled pins 7 and 8 at the moments of passing under them. In this case, the permanent magnet 11 is set on a graduated scale of the flywheel in a position corresponding to the beginning of the weft plotter, against the mark of 140 ° on narrow machines and against the mark of 105 ° on the wide. In turn, the permanent magnet 12 is set to the position corresponding to the extremely late arrival of the duck plotter to the receiving box, i.e. against the mark of 295 ° on narrow machines and against the mark of 300 ° on the wide.

The control element control circuit b contains a trigger driver 13 of the control interval 13 performed on logic elements AND 14 and NOT 15. The output of the trigger driver 13 is connected to the first input of the coincidence circuit 16 containing logic element K 17. The consumption sensor 1 is connected to the second input of the coincidence circuit 16 threads. The output of the coincidence circuit 16 is connected to the input of the pulse expander 18, which is a standby multivibrator assembled on AND 19 and NOT 20 gates. The output of the control circuit 6 is connected to the executive stop mechanism.

On multicolor weaving machines, the number of the above elements is determined by the number of threads to be observed.

The device works as follows.

In the initial state, before the beginning of the insertion of the weft-laying weft, the weft thread is weakened, as a result of which the contacts.

In the initial period of insertion of the weft filler, the weft thread, when tensioned, opens the contacts of the sensor 1, so that the zero state is set at the second input of the coincidence circuit 16. Since the beginning of the battle corresponds to 140 + 3 ° rotation of the main shaft on narrow machines (105 + 3 ° on

wide), then at this moment under the influence of the permanent magnet 11 the magnetically controlled contact 7 of the sensor 4 of the beginning of the control interval is triggered. The signal from the sensor 4 is fed to the input element And 14 trigger driver 13, setting the latter in one state. Thus, with a normally proceeding process of laying the weft yarn, a single state is maintained at the output of the coincidence circuit during the entire control interval.

At a certain value of the angle of rotation of the main shaft of the machine, the permanent magnet 12 mounted on the rim of the graduated scale of the flywheel when passing through the magnetically controlled contact 8 of the sensor 5 of the end of the control interval causes it to trigger. The signal from sensor 5, applied to the second input of the trigger generator 13, overturns it, while its zero state is set at its output. If within the control interval there is a violation of the process of laying the weft thread, breakage (loss) of the weft thread during the movement of the plotter, loss of the weft when creating a compensator and weft brake of the technologically necessary tension, the plotter’s undershoot, the contacts of sensor 1 of the thread consumption also close to the second input of the circuit 16 coincidence ^ signal is given. At the output of the coincidence circuit 16, a zero potential is set, which starts the waiting multivibrator 18, which forms a stop pulse.

The guest follower, in the most unfavorable case when the duck laying process is disturbed immediately before the plotter arrives in the receiving box, is triggered by the elements of the device, clearly shown in the diagram (see Fig. 4).

Due to the reliability and speed of the proposed device, its use to control the weft yarn on shuttleless looms ensures timely detection of disturbances in the normal process of weft laying in the throat of the warp and prevents duct defects in the fabric due to increased reliability by reducing sensitivity to external interference in practice the probability of false alarms of the stop mechanism is excluded.

Claims (1)

Claim A device for automatic weft stop of the shuttleless loom, containing a sensor for the start of the control interval with a permanent magnet on the flywheel of the main shaft of the machine and a sensor for the end of the cont5 757615 6 The pitch interval connected to the trigger driver inputs, the thread consumption sensor connected to the first input of the coincidence circuit, the second input of which is connected to the trigger driver output, and the output by means of the pulse expander - with the executive mechanism, characterized in that contains an additional permanent magnet, | located on the flywheel of the main shaft of the machine with an offset along the circumference and the height of the flywheel relative to the first magnet, and the sensitive elements of the sensors of the beginning and end of the control interval are made in the form of reed switches placed on the frame of the machine opposite the flywheel in the zone of action of the corresponding magnet.