Abstract: A method of stopping a loom, whose operation is controlled by a microcomputer, at a predetermined position thereof is disclosed herein. In view of the phenomenon that the load on loom operation is varied with the operating cycles thereof depending on the texture of fabric to be woven, but the variation takes place in repeated cycles of similar patterns each including different phases in succession of a known number, the method according to the invention comprises the steps of detecting the deviation of the actual stop position from the predetermined position resulting from the preceding loom braking operation, executing arithmetic operation on data regarding said deviation for compensation thereby to adjust the position at which brake is to be applied in the current braking operation, and applying brake when said position determined through said arithmetic operation is reached by the loom, wherein such steps are carried out in each group of the phases that correspond to each other in similarity.

Abstract: A method positioning control is disclosed, to stop mechanisms of a loom at predetermined positions when stopping the loom operation, in which the loom is directly controlled by a microcomputer. In the method, correction is made with respect to a predetermined position for commencing a braking operation so as to stop the mechanisms at said positions correctly. The above-mentioned correction is conducted by, first, obtaining the positional deviation between the actual stop position and the predetermined stop position during the last braking operation, second, using the obtained positional deviation for effecting identical correction regarding the next braking operation, etc. repeated over and over.

Abstract: An arrangement to preclude false starting and stopping of a motor driving a loom in accordance with start and stop control signals from a microprocessor control unit susceptible to noise. The motor is connected to start only upon coincidence between the control unit start signal and energization of a manually operated start switch; and to stop in response to either the control unit stop signal or energization of a manually operated stop switch.

Abstract: A weft yarn detector for detecting weft yarn inserted into a weft yarn guide passage formed by a series of weft yarn guide members mounted on a slay of a loom is disclosed. The detector comprises a weft yarn detecting body with two supporting portions disposed opposite to each other on the opposite sides of the weft yarn guide passage, and weft yarn detecting elements supported by the two supporting portions. According to this invention, the detector is characterized by a flexible, thin, printed-wiring plate attached to the weft yarn detecting body and electrically connecting the weft yarn detecting elements to an external control system.

Abstract: A method and an apparatus for controlling operation of at least one operating element of a loom on the basis of a reference signal are disclosed. A rotational position signal developed during each weaving cycle of the loom is compared with the reference signal to issue a rotational angle signal indicating an angle through which the loom has been rotated with respect to a reference angular position. By utilizing this rotational angle signal, the timing of the operation of any operating element can be determined.

Abstract: Disclosed is a method of sensing an abnormality in a weft detecting device which is employed in a loom in order to detect whether a weft is present in a predetermined interval corresponding to a set crank angle range within one revolution of the crank. When the weft detecting device generates a signal in the predetermined crank angle range excluding the weft detection angle range, the signal is regarded as an abnormal signal. The abnormal signal is processed by circuitry to detect the abnormality in the weft detecting device. Thus, when it is impossible to detect a weft insertion error because of some abnormality in the weft detecting device, the presence of the abnormal signal is utilized to issue an alarm or to stop the operation of the loom.

Abstract: A device for inserting a weft yarn in a shed of the jet operated weaving machine provided with a control means for controlling the carrying action of the weft yarn, which is carried by a plurality of pressure fluid flows through a guiding channel formed in a comb arranged in parallel condition to a reed. The comb comprises a plurality of guiding plates and an air escaping passage formed between every two adjacent guide plates in such a condition that the quantity of the escaping air which flows through each escaping passage is maximum at a predetermined portion of each escaping passage. The above-mentioned control means comprises the above-mentioned escaping passages.