GB711064A - Improvements in electro-mechanical gearings for vehicles and so forth - Google Patents

Abstract

711,064. Transmitting mechanical power. AKERMAN, O., and AKERMAN, L. O. July 27, 1951 [July 31, 1950], No. 17906/51. Drawings to Specification. Class 38(4) Relate to a variable-speed electromechanical power transmission system, particularly for vehicles, of the kind wherein the three elements of an epicyclic gear are coupled, respectively, to primemover, the load and a dynamo-electric machine, the last of which is electrically connected to a similar machine coupled to one of the other two elements of the gear and wherein the first machine has fixed separate excitation and the second a reversible separate excitation. According to the invention, the system is such that (1) with the first machine stalled and the prime-mover running at normal speed, the load shaft runs at a medium speed which is considerably higher than half of the continuous speed range afforded by the electric machines; (2) during starting, the prime-mover is accelerated to normal speed from an initial speed which is at least as low as half said continuous speed range and preferably lower than half normal speed of the prime-mover; and (3) the first electric machine is so coupled to its element of the gear as to be capable of causing therein a reactional torque moment (preferably near maximum speed of the machine) equal to the torque moment produced therein by the primemover. A shiftable step gear providing steps equal to the said continuous speed range, may be inserted the output member of the epicyclic gear and the load shaft.