摘要 |
A device for the photoelectric supervision of a warp loom for irregularities in the yarn supply of a yarn sheet has an infrared radiation source and receiver, which are arranged so that the infrared beam is alternately interrupted and released, in time with the frequency of the oscillating eye needles, by the needles as well as by the yarns passing therethrough. This periodic supervisory signal sequence is periodically processed by a gating circuit only during a preset gating time period (TX) within each beam release phase (Tp). The signal values issued in each window pulse gating phase are compared in a comparator circuit with a comparison value. If the latter is not attained, a control signal is generated for the warp loom.
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