Oil pump with selectable outlet pressure

Abstract

An oil pressure relief valve for use in the oil pump lubrication system of an internal combustion engine is controlled by both oil pump outlet pressure and by pilot pressure from a pilot valve which is selectively applied by a control member, preferably a two-way valve that is operated by the engine control module. The pilot valve selectively supplies one of the oil pump outlet pressure or the engine gallery pressure to the control member which selectively supplies pilot valve pressure to the oil pump pressure relief valve which has a single piston. The pilot valve includes first and second pistons for selectively controlling back pressure from the pressure relief valve and for managing changes in oil pressure due to changes in the engine gallery to maintain a virtually constant pressure even as oil pump speed increases when the control member connects the pilot valve to the pressure relief valve resulting in a fuel economy benefit and improved control of the oil pump pressure.

Description

[0001] Cross References to Related Applications [0002] This application claims priority and priority to U.S. Provisional Patent Application No. 61 / 437,365, entitled "OIL PUMP WITH SELECTABLE OUTLET PRESSURE," filed January 28, 2011 in the name of Williamson et al. Interest, the entire content of this application is incorporated herein by reference for all purposes. technical field [0003] The present disclosure generally relates to oil pump assemblies including pressure relief valves for managing oil pump discharge pressure and control valve pilot pressure. More specifically, the present disclosure relates to pressure relief valves having a pilot valve in communication therewith to find particular application in fixed displacement pump lubrication systems for internal combustion engines. Background technique [0004] It is generally known to provide an internal combustion engine that includes an oil pump assembly that pumps engine oil through the engine to pass through v...

AI Technical Summary

Problems solved by technology

[0007] Although such conventional oil pressure relief valves are simple and reliable, the work of the oil pump is difficult because the oil pump operates to increase the oil pressure to a preset pressure level even though a lower oil pressure may be suitable to provide satisfactory lubrication of the engine components. relatively high consumption

The high power consumption of the oil pump is equivalent to a decrease in fuel efficiency which is a disadvantage

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