Patent ID: 8597003
Filing Date: 2013-12-03
Classification: F04C,Y10T

Abstract:
1. A lubrication system for a power transmission device, comprising: a variable displacement vane pump having a pivotable pump control ring for varying the displacement of the pump; and a control system operable to vary the displacement of the pump during operation of the pump to achieve an output pressure selected from a continuously variable range of output pressures from the pump which are independent from the operating speed of the pump, the control system including a linear actuator coupled to the control ring for moving the control ring between minimum and maximum pump displacement positions, the linear actuator including an electric stepper motor for bi-directionally rotating a nut threadingly engaged with an axially moveable actuator shaft and a coupler interconnecting the actuator shaft and the control ring, the coupler having multiple degrees of freedom to allow concurrent axial movement of the actuator shaft and rotation of the control ring.