Patent ID: 7245053
Filing Date: 2007-07-17
Classification: H02K

Abstract:
1. An electric motor assembly comprising: an electric motor having a first end and a second end spaced from said first end and a motor shaft extending along a first axis between a first tip cantilevered from said second end and a second tip spaced from said first tip along said first axis; a worm gear disposed on said motor shaft between said second end and said first tip for rotation with said motor shaft about said first axis; a housing having an internal surface with a first portion correspondingly shaped with respect to said first end to locate said electric motor in said housing and also having a second portion disposed along said first axis spaced from said first tip; a first thrust bearing disposed between said first tip and said second portion and limiting movement of said motor shaft along said first axis in a first axial direction; and a second thrust bearing disposed adjacent said second tip along said first axis and limiting movement of said motor shaft along said first axis in a second axial direction opposite said first axial direction wherein said motor shaft being urged to move in said first axial direction in response to rotation of said worm gear in a first angular direction and being urged to move in said second axial direction in response to rotation of said worm gear in a second angular direction opposite said first angular direction; wherein engagement between said first tip and said first thrust bearing during rotation in said first angular direction resists rotation of said motor shaft in said first angular direction with a first force of friction and wherein engagement between said second tip and said second thrust bearing during rotation in said second angular direction resists rotation of said motor shaft in said second angular direction with a second force of friction substantially the same as said first force of friction; and wherein said second tip is spaced from said second thrust bearing during rotation of said motor shaft in said first angular direction.