Opto-electronic yarn monitor for loom or knitter - has transparent plate with groove as yarn guide between light reflector and sensor

摘要

Yarn monitor has a transparent plate (3) as the yarn guide between the light reflector and sensor in the monitor housing. The plate (3) has a V-shaped groove at its upper side, in the scanning zone, as a guide path for the yarn (1), with a curved groove base, and expanded entry and exit ends. The sensor (2) is a reflection sensor, and the light is emitted by a photo diode (5) with a focusing lens (6) to be received by a light conductor (7) and photo detector (8) centrally at the focusing lens (6). The under side of the plate (3) has an opening (21) to hold the sensor (2), as a blind drilling, and the focusing lens (6). The sensor (2) and the plate (3) are held by a common mounting (25) with eyelets (28,29) for the yarn (1) at the entry and exit ends of the guide groove. The plate (3) is only transparent to light passage at the holder opening (21). At least one additional yarn guide (26,27) is at the plate (3) area, which are shaped and/or located so that the yarn (1) is held at the base of the guide groove at least in the monitoring zone. ADVANTAGE - The yarn can be monitored and controlled under all working conditions, using small light emitting and receiving components.