GB640238A - Improvements in electrical torque-measuring devices - Google Patents

Abstract

640,238. Electric dynamometers. MORTSELL, A. M., and OHLIN, P. Jan. 6, 1947, No. 381. [Class 40 (i)] [Also in Groups XIX and XXXII] A coupling unit adapted to transmit and measure torque between two rotatable members includes two discs adapted to be rigidly connected one to each respectively of said members and interconnected by yielding means for transmitting the torque, and an electrical torque-measuring means comprising firstly an electrical circuit containing flux-producing means mounted on one of said discs and a flux-control element mounted on guide means on the same disc and secondly a member for actuating the flux-control element mounted on the other of said discs, said flux-control element and said flux-producing means being relatively displaceable in response to relative rotary movement of said discs. Torque is transmitted between shafts 3 and 8, Figs. 5, 6 by peripherally-arranged compression springs 23 acting between discs 5 and 7 keyed respectively to the shafts. AT-shaped member 43 is pivoted to the disc 5 and to a twisted blade spring 46 secured to the disc 7 and carries an adjustable screw 42 by which it moves a sprung rod 11 longitudinally when the discs 5 and 7 rotate relatively to one another. The movement of the rod 11 is passed through damping means (see Group XXXII), to an iron core 12 guided in a cylinder carried by the disc 5, the core 12 being adapted to vary an air gap of an electromagnet 10 secured to the disc 5 and connected through the shaft and an insulated slip ring 24 to a source of alternating current and an ammeter. In an alternative arrangement, the discs 5, 7 may be coupled by a co-axial helical spring. The electromagnet and a damped iron core associated therewith are secured on the outer plane face of the disc 5 and the position of the core is controlled by an arm carried by the other disc 7. In a different embodiment, Fig. 4, the movable plates of a condenser are carried by an arm 16 pivoted to the disc 5 to which the fixed plates are secured and the position of the arm is controlled by a rod 1,5 secured to the other disc 7. The fixed and moving. condenser plates are connected through slip rings in circuit with a source of alternating current and an ammeter.