GB261802A - Improvements relating to refrigerating machines - Google Patents

Abstract

261,802. Klenow, E. W. R. Nov. 23, 1925, [Convention date]. Brakes, electric and magnetic. -, In encased refrigerating machines, particularly such based upon the Audriffen-Singrun principle and comprising a freely mounted part which is subject to a turning moment due to a rotating part but the rotation of which it is desired to prevent such rotation is prevented or restrained by fitting the part with an armature subject to a magnetic field which is stationary or rotates only at a slow speed. The machine shown comprises an evaporator 1 and a casing 2 driven by the shaft 3. The casing 2 encloses a compressor 4 freely mounted on the shaft 3 and in order to prevent or restrain the rotation of the compressor so that the pumping action may he effected, it is provided with an annular iron core 7 secured to a sleeve 5 and arranged coaxially with a second core 8 carried by a support 9 secured to the casing 2. The core 8 is provided with a polyhpase alternating current winding 12 such as to produce a field that rotates at a speed substantially equal and opposite to that of the core and the core 7 may be fitted with a squirrel cage or other short circuit winding 13. The general construction of the braking device is thus similar to that of an asynchronous alternating current induction motor, the stator 8 of which rotates in a direction opposite to that of the rotary field and the rotor 7 of which is stationary or rotates at a slow speed. The field may instead be produced by disposing a magneto outside the rotary casing. According to the Specification as open to inspection under Sect. 91 (3) (a) the braking device may be used in connection with any encased machine having a freely suspended part which is subject to a turning movement. This subjactmatter does not appear in the Specification as accepted.