JPH027898Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to an integral feeler automatic adjustment device in a loom.

(Prior Art) In a loom, cloth is woven by weaving one weft into the warp, and the machine is stopped when a feeler detects a mispick in the weft. There are other types of feelers, such as an integral feeler, and the integral feeler has a structure as shown in FIG. That is, the weft is detected by the feeler head integrated with the reed when the reed is driven in, and the detection signal is amplified by the amplifier 1 and input to the integrating circuit 2. As shown in FIG. 3, the output signal of the amplifier 1 becomes low level when the feeler head detects the weft, and a pulse is applied to the integrating circuit 2 from the proximity switch at the timing when weft mispick is to be detected. This proximity switch is turned on and outputs a pulse when the main shaft rotates within a certain angle range every time the main shaft of the machine rotates once and one weft yarn is woven. The integrating circuit 2 integrates the output signal of the amplifier 1 during the pulse application period T every time a pulse is applied from the proximity switch, and the integrated value corresponds to the weft detection state of the filler head within the pulse application period T. A current-carrying type filler head using a pair of electrodes or an optical type filler head is used as the filler head, and the setting circuit 3 detects that the integral value of the integrating circuit 2 exceeds a set value due to weft mispick and outputs an output signal. Output.

(Problem that the invention aims to solve) In a loom, the operating speed of the machine (the number of rotations of the main shaft) is varied depending on the type of cloth being woven.
By varying the operating speed, the operating time of the proximity switch changes and the width T of the pulse from the proximity switch changes. Therefore, the time during which the integrating circuit 2 integrates the output signal of the amplifier 1 changes, and the criterion for weft mispick changes, and the operator has to make manual adjustments to eliminate this fluctuation.

(Means for Solving the Problems) The present invention includes a feeler head that detects weft mispick in a loom, an integrating circuit that integrates the output signal of the feeler head every period in which a pulse is input from a proximity switch in the loom, and a and means for detecting that the integral value of the integrating circuit has reached a set value, the integral feeler comprising automatic adjusting means for adjusting the time constant of the integrating circuit in accordance with the width of the pulse from the proximity switch. .

(Function) As the operating speed of the loom is varied, the width of the pulse from the proximity switch changes, and the automatic adjustment means adjusts the time constant of the integrating circuit in accordance with the width.

(Example) FIG. 1 shows an embodiment of the present invention.

This embodiment is an integral feeler for the above-mentioned loom, in which a pulse width detection circuit 4 and an automatic time constant adjustment circuit 5 are provided to automatically adjust the time constant of the integral circuit 2 according to the operating speed of the machine. The automatic time constant adjustment circuit 4 uses a proportional circuit. The pulse width detection circuit 4 detects the width of the pulse from the proximity switch, and based on this output signal, the automatic time constant adjustment circuit 5 adjusts the integration time constant of the integration circuit 2 according to the width T of the pulse from the proximity switch. In other words, by increasing the integration time constant of the integrator circuit 2 as the pulse width T becomes wider and decreasing it as the pulse width T becomes narrower, the criterion for weft mispick can be set with respect to changes in machine operating speed (rotational speed of the main shaft). Make it constant.

Note that since the width T and frequency of the pulse from the proximity switch are inversely proportional, the same effect can be obtained by using a frequency demodulation circuit instead of the pulse width detection circuit 4 to detect the frequency of the pulse from the proximity switch. . Further, the integrating circuit 2 may be of an analog type or a digital type.

(Effects of the invention) As described above, according to the invention, the time constant of the integrating circuit in the integral feeler of the loom is adjusted according to the width of the pulse from the proximity switch, so the operating speed of the machine can be varied and weft mispick can be prevented. Judgment criteria do not fluctuate, eliminating the need for operator adjustments.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.
FIG. 2 is a block diagram showing an example of an integral feeler, and FIG. 3 is a timing chart of the same integral feeler. 4...Pulse width detection circuit, 5...Automatic time constant adjustment circuit.

Claims (1)

[Scope of utility model registration request] There is a feeler head that detects weft mispick in the loom, an integration circuit that integrates the output signal of this feeler head every period when a pulse is input from a proximity switch in the loom, and a feeler head that detects when the integral value of this integration circuit has reached a set value. An integral feeler automatic adjustment device comprising automatic adjustment means for adjusting the time constant of the integration circuit according to the width of the pulse from the proximity switch.