Patent ID: 6739305
Filing Date: 2004-05-25
Classification: F01M

Abstract:
An oil pump for an internal combustion engine, comprising:a power pump that is rotated by a drive shaft of the internal combustion engine; an electric pump that is rotated by a driving force of an electric motor, the power pump and the electric pump being arranged in parallel with each other; and a check valve that is disposed in an oil passage for connecting a discharge port of the power pump to a discharge port of the electric pump such that an oil is allowed to flow only in a direction from the electric pump to the power pump, wherein the electric pump is driven when an oil temperature becomes about 80Â° C. or higher, and a revolution speed of the internal combustion engine becomes at most about 2000 rpm, so that a discharge pressure is held in a range of about 60 to about 120 kPa.