GB811704A - Improvements in or relating to thread detecting devices - Google Patents

Abstract

811,704. Knitting-machines. TRIP-LITE Ltd. July 4, 1955 [July 20, 1954], No. 21134/54. Class 74 (2). A yarn detecting device for a circular machine comprises one or more stationary guides 22 and a guide 27 mounted on a spring-loaded movable lever 26, the lever being cranked at 30 for attachment of the spring 37 which is secured to a member 33 such that the effect of the spring is least when the lever and eye 27 are in the normal yarn feeding position but which effect increases as the lever moves its eye away from the normal path of the yarn. The lever is pivoted in a casing 18 such that with the yarn in its normal position the pull of the spring on the crank passes in line with the pivot point. As the lever moves the effective leverage of the crank is increased and the spring exerts an increasing pull on the yarn. In the event of yarn failure or undue slackness the crank engages an electrical contact 38 to cause stoppage of the machine. The tension of the spring may be varied by a screw 35 adjusting the position of the member 33. If desired the lever may move in either or only one direction from the position it occupies when the yarn is feeding normally. Alternatively a weight, which may be changed, may be attached to the crank 30 or a compression spring may replace the tension spring, the crank being suitably provided to accommodate the compression spring in this case.