Electric pump for a hybrid vehicle

Abstract

A hydraulic system for a hybrid module which is located between an engine and a transmission includes a parallel arrangement of a mechanical pump and an electric pump. Each pump is constructed and arranged to deliver oil to other portions of the hydraulic system depending on the operational mode. Three operational modes are described including an electric mode, a transition mode, and a cruise mode. Various monitoring and control features are incorporated into the hydraulic system.

What is claimed is: 
     
         1 . An electric pump for a hybrid vehicle comprising:
 a pump body defining a flow inlet conduit and a flow outlet conduit;   an electric motor positioned within said pump body, said electric motor including a stator; and   a gerotor positioned within said pump body, said gerotor being constructed and arranged so as to be generally concentric with and positioned radially inwardly of said stator.   
     
     
         2 . The electric pump of  claim 1  wherein said electric motor further includes a two-piece shaft. 
     
     
         3 . The electric pump of  claim 1  wherein said electric motor further includes a stainless steel liner. 
     
     
         4 . The electric pump of  claim 1  wherein said electric motor further includes a permanent magnet liner. 
     
     
         5 . The electric pump of  claim 4  wherein said permanent magnet liner includes a plurality of permanent magnets received within a stainless steel liner. 
     
     
         6 . The electric pump of  claim 1  wherein the gerotor includes an outer rotor and an inner rotor. 
     
     
         7 . The electric pump of  claim 1  which further includes a one-way valve positioned in said flow outlet conduit. 
     
     
         8 . The electric pump of  claim 1  which further includes a pressure regulating valve positioned in said flow outlet conduit. 
     
     
         9 . The electric pump of  claim 1  which further includes a dowel pin for use in alignment of said electric pump with a hybrid module. 
     
     
         10 . The electric pump of  claim 9  wherein said dowel pin defines a pressure lock groove. 
     
     
         11 . The electric pump of  claim 1  which further includes a cover which is attached to said pump body. 
     
     
         12 . The electric pump of  claim 11  wherein a tamper-proof threaded fastener is used to attach said cover to said pump body. 
     
     
         13 . The electric pump of  claim 11  which includes an electrical connector which is attached to said cover. 
     
     
         14 . The electric pump of  claim 13  wherein a tamper-proof threaded fastener is used to attach said electrical connector to said cover. 
     
     
         15 . An electric pump for a hybrid vehicle comprising:
 a pump body;   an electric motor positioned within said pump body, said electric motor including a stator, said stator defining an interior volume; and   a gerotor positioned within said pump body, said gerotor being constructed and arranged so as to be generally concentric with said stator and positioned within said interior volume of said stator.   
     
     
         16 . The electric pump of  claim 15  wherein said electric motor further includes a two-piece shaft. 
     
     
         17 . The electric pump of  claim 15  wherein said electric motor further includes a stainless steel liner. 
     
     
         18 . The electric pump of  claim 15  wherein said electric motor further includes a permanent magnet liner. 
     
     
         19 . The electric pump of  claim 18  wherein said permanent magnet liner includes a plurality of permanent magnets received within a stainless steel liner. 
     
     
         20 . An electric pump for a hybrid vehicle comprising:
 a pump body including a flow inlet and a flow outlet; and   an electric motor and gerotor arrangement position within said pump body, said arrangement including a generally concentric combination of a stator, a metal liner, a permanent magnet liner, an outer gear, an inner gear and a shaft.   
     
     
         21 . The electric pump of  claim 20  wherein said metal liner is a stainless steel liner. 
     
     
         22 . The electric pump of  claim 20  wherein said shaft is constructed and arranged as a two-piece shaft.