Motor dust cover design and interface with coupling

A motor vehicle electric motor assembly, comprising:

• a motor housing having an annular wall extending from a housing first end to an opposite housing second end about a central axis to circumferentially bound a cavity, said housing first end having a base configured to support a bearing housing and said housing second end being open;
• a motor shaft extending along said central axis between a shaft first end and a shaft second end;
• a rotor fixed to said motor shaft for rotation about said central axis;
• a stator supported by said annular wall in radially spaced relation from said rotor to define an annular motor gap between said stator and said rotor;
• a bearing fixed in said bearing housing to support said shaft first end for rotation about said central axis;
• and
• an end cover assembly fixed to said housing second end, said end cover assembly having a motor shaft opening extending about said central axis with an outer periphery of said motor shaft opening supporting said shaft second end for rotation about said central axis,
• wherein said end cover assembly includes an end cover having an end cover outer periphery fixed to said annular wall adjacent said housing second end, wherein said end cover outer periphery is press fit into an interference fit against an inner surface of said annular wall of said motor housing, wherein said end cover outer periphery has a plurality of protrusions extending radially outwardly into said interference fit.

A motor vehicle electric motor assembly, comprising:

• a motor housing having an annular wall extending from a housing first end to an opposite housing second end about a central axis to circumferentially bound a cavity, said housing first end having a base configured to support a bearing housing and said housing second end being open;
• a motor shaft extending along said central axis between a shaft first end and a shaft second end;
• a rotor fixed to said motor shaft for rotation about said central axis;
• a stator supported by said annular wall in radially spaced relation from said rotor to define an annular motor gap between said stator and said rotor;
• a bearing fixed in said bearing housing to support said shaft first end for rotation about said central axis;
• and
• an end cover assembly fixed to said housing second end, said end cover assembly having a motor shaft opening extending about said central axis with an outer periphery of said motor shaft opening supporting said shaft second end for rotation about said central axis,
• wherein said end cover assembly includes an end cover having an end cover outer periphery fixed to said annular wall adjacent said housing second end, wherein said end cover assembly includes a shaft seal annulus fixed to said end cover, said shaft seal annulus having said motor shaft opening, wherein said motor shaft opening is sized providing an interference fit with an outer running surface of said motor shaft, said end cover has a first modulus of elasticity and said shaft seal annulus has a second modulus of elasticity, said second modulus of elasticity being less than said first modulus of elasticity.

A motor vehicle electric motor assembly, comprising:

• a motor housing having an annular wall extending from a housing first end to an opposite housing second end about a central axis to circumferentially bound a cavity, said housing first end having a base configured to support a bearing housing and said housing second end being open;
• a motor shaft extending through said cavity along said central axis between a shaft first end and a shaft second end;
• a rotor fixed to said motor shaft for rotation about said central axis within said cavity;
• a stator supported by said annular wall in said cavity in radially spaced relation from said rotor to define an annular motor gap between said stator and said rotor;
• a bearing fixed in said bearing housing to support said shaft first end for rotation about said central axis;
• and
• an end cover assembly fixed to said housing second end, said end cover assembly having a motor shaft opening extending about said central axis with an outer periphery of said motor shaft opening supporting said shaft second end for rotation about said central axis in an interference fit without a roller bearing,
• wherein said end cover assembly includes an end cover having an end cover outer periphery fixed to said annular wall adjacent said housing second end, and a shaft seal annulus fixed to said end cover, said shaft seal annulus having said motor shaft opening, wherein said end cover has a first modulus of elasticity and said shaft seal annulus has a second modulus of elasticity, said second modulus of elasticity being less than said first modulus of elasticity.

A method of assembling a motor vehicle electric motor assembly, comprising:

• providing a motor housing having an annular wall bounding a cavity extending about a central axis from a housing first end having a base to an opposite housing second end;
• fixing a bearing to said base for rotation about said central axis;
• disposing a stator in said cavity;
• disposing a motor shaft having a rotor fixed thereto within said cavity and disposing a shaft first end of said motor shaft through a bore of said bearing, with a shaft second end of said motor shaft extending beyond said housing second end and with the stator being in radially spaced relation from said rotor to define an annular motor gap between said stator and said rotor;
• fixing an end cover assembly to said housing second end and supporting said shaft second end for rotation about said central axis within a motor shaft opening of said end cover assembly with an outer periphery of said motor shaft opening having an interference fit with an outer running surface of said motor shaft;
• and
• providing said end cover assembly having an end cover, and fixing an end cover outer periphery of said end cover to said annular wall adjacent said housing second end, and having a shaft seal annulus fixed to said end cover, wherein said shaft seal annulus has said motor shaft opening, wherein said end cover has a first modulus of elasticity and said shaft seal annulus has a second modulus of elasticity, said second modulus of elasticity being less than said first modulus of elasticity.