GB924276A - Improvements relating to arrangements for measuring load on ropes - Google Patents

Abstract

924,276. Devices for measuring load in ropes. GUTEHOFFNUNGSHUTTE STERKRADE A.G. Oct. 7, 1959 [Oct. 7, 1958], No. 34056/59. Class 40 (1). An element for measuring the load on a rope of an installation for hoisting a car or skip is in. corporated in a rope connector and a stationary indicator is connected by a transmitting line to the measuring element. The transmitting line is divided into two sections, one connecting the measuring element to a junction secured to the car or skip and the other adapted to connect this junction to the indicator. As shown, a split ring 7, Fig. 3, is incorporated in each rope of a four-fall hoisting installation of a mine shaft, the width of the slot in each ring being measured by an inductive displacement meter comprising coils 9 and magnet 9<SP>1</SP>, or by a potentiometer, Fig. 4, the resistance winding 15 of which is tapped by a sliding contact 16, controlled by plunger 17, in a Wheatstone bridge. A cable 10 leads from each measuring element to a multiple plug socket mounted in the car or to a sliding contact carried by the car, a bank of indicators mounted at the pit mouth or pit bottom being connected to a multiple plug or to a stationary contact bar, respectively. The slotted ring and attached detector may be replaced by a dynamometer for delivering electric values, or a magneto-elastic dynamometer incorporating a ferro-magnetic member the magnetisation of which varies in accordance with the mechanical stresses prevailing therein. Alternatively, known extensometers having a wire the resistance of which varies in accordance with rope stress, or dynamometers comprising a vibrating wire the frequency of vibration of which is a function of the stress in the rope, may be used.