Patent ID: 9458841
Filing Date: 2016-10-04
CPC Classification: F04B

Claim Text:
1. A lubricant oil circulation system for circulation of lubricant oil of an electric motor in a hybrid electric vehicle that is powered by and has, as power sources, the electric motor operable on electric power supplied from an electrical storage device and an internal combustion engine, comprising: an electric pump operable on electric power stored in the electrical storage device to circulate the lubricant oil in an oil flow path that includes the electric motor interior structure; a mechanical pump operable on driving power of the internal combustion engine to circulate the lubricant oil in the oil flow path; and a controller configured to detect abnormality in operation of the electric pump derived from viscosity of the lubricant oil and to activate the mechanical pump for using operation of the mechanical pump on driving power of the internal combustion engine upon detecting the abnormality in operation of the electric pump, wherein the controller is configured to detect elimination of the abnormality in operation of the electric pump derived from viscosity of the lubricant oil and the controller controls the mechanical pump to continue operating for a predetermined duration of time, which begins immediately after detecting elimination of the abnormality of the electric pump derived from viscosity of the lubricant oil, and wherein the controller compares an amount of time after detecting elimination of the abnormality of the electric pump derived from viscosity of the lubricant oil with the predetermined duration of time and the controller shuts down the mechanical pump upon lapse of the predetermined duration of time.