Integrierte Elektromotor-Hydropumpeneinheit mit Motordrehrichtungserkennung

摘要

An electrohydraulic systems includes an electric motor (12 Fig. 1 not shown) and a hydraulic pump (14) interconnected by a drive shaft (16) and integrated within a unitary housing (18). A circuit (26) for detecting phase relationship of the multi-phase electrical input power applied to the motor, and thereby determining direction of rotation of the motor, includes facility R1-4, C1 for providing a first electrical signal Vb at predetermined phase relationship (e.g. 60 degree lagging) to one of the input power phases V1, providing a second electrical signal Vc that either leads or lags (e.g. by 60 DEG ) the one input power phase V1 as a function of phase direction among the input power phases, and indicating phase direction of the electrical input power as a function of a difference between such first and second signals. If phase rotation is correct, Va and Vb are in phase, therefore there is no indication. For incorrect rotation, diodes D1, D2 flash alternatively and an audible alarm 38 is energised. <IMAGE>