Fluid bearing with asymmetrical groove pattern
AssigneeSynektron Corporation
InventorRobert J. Hensel
Life of this patent
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Abstract
An electric motor construction includes a rotor housing and sleeve which surrounds a shaft/thrust plate. The thrust plate is enclosed in a dead end cavity and is surrounded by a fluid which forms a fluid bearing. The shaft has asymmetrical grooves which create a net pressure gradient from a capillary seal formed near the bottom of the shaft toward the dead end cavity. This helps maintain the capillary seal and reduce the risk of cavitation.
Claims10
In an electric motor including a shaft and a housing, said housing having a sleeve for receiving said shaft, said shaft and said sleeve defining a gap therebetween, a hydrodynamic bearing construction comprising a single dead end thrust plate coupled to said shaft at a first end thereof, said thrust plate having an upper and a lower surface, a hydrodynamic fluid filling said gap between said shaft and said sleeve and generally surrounding said thrust plate, said shaft including at least one set of asymmetrical grooves for creating a pressure gradient in said hydrodynamic fluid tending to create a zone of higher pressure toward said single dead end thrust plate.
A fluid bearing construction for an electric motor comprising:
- (a) a shaft;
- (b) a thrust plate coupled to a first end of the shaft;
- (c) a housing having a journal sleeve for receiving the shaft with a first portion having a diameter slightly larger than the shaft and a second portion having a second larger diameter slightly larger than the thrust plate;
- (d) an end cap inserted into the second diameter portion of the housing sealing the thrust plate off from the outside atmosphere and forming an internal cavity in said housing;
- and
- (e) a bearing fluid surrounding the thrust plate and the shaft and forming a capillary hydrostatic seal near a second end of the shaft opposite said first end.
Dependencies are inferred from the claim text.