Brushless motor having lubrication system for upper and lower bearings
First Claim
1. A brushless motor comprising:
- a stator including a stator core and coil winding portions, said stator core having a through hole formed therein;
an upper bearing and a lower bearing;
an upper bearing holder mounted in said through hole of said stator core, having at least one oil passage hole formed therein and holding said upper bearing;
a lower bearing holder mounted in said through hole of said stator core and holding said lower bearing, said lower bearing holder having at least one oil passage hole formed therein in fluid communication with said at least one oil passage hole of said upper bearing holder;
a rotary shaft rotatably held by said upper bearing and said lower bearing;
a rotor secured to said rotary shaft and including permanent magnets provided along a rotary direction;
an upper bearing stopper, provided between said upper bearing and said upper bearing holder, securing said upper bearing to said upper bearing holder, said upper bearing stopper having at least one oil passage hole formed therethrough;
a first felt located under said at least one oil passage hole of said upper bearing stopper and contacting said upper bearing;
a lower bearing stopper, provided between said lower bearing and said lower bearing holder, securing said lower bearing to said lower bearing holder;
a second felt located under said at least one oil passage hole of said lower bearing holder and contacting said lower bearing; and
a thrust stopper for axially supporting said rotor, said thrust stopper having a through hole with said rotary shaft mounted therethrough and including a cylindrical portion surrounding said through hole, an oil guide being constituted by a lower surface of said cylindrical portion.
3 Assignments
0 Petitions
Accused Products
Abstract
The present invention offers a simple structure that facilitates the mounting of bearings, that maintains lubricating oil at a sufficient level in the bearing portions and that maintains an optimal distance between a rotor and a case housing for preventing freezing, for preventing reduction of the capacity and for preventing noise. Bearing stoppers provided between the bearings of the brushless motor and the bearing holders, which hold the upper end edge of each bearing, are secured at a projection formed at the internal circumferential surface of each bearing holder. A felt, which comes in contact with the lower portion of each bearing stopper and also comes in contact with the bearing at one side is provided, with holes communicating with the felt formed at the lower surface of the bearing stopper. In addition, the lower limit of the distance h between the lower end of the rotor and the upper end surface of the case housing is set at 1.5 mm. This prevents water from forming a connection between the rotor and the case housing due to capillary action and surface tension. In addition, the upper limit of the distance h is set at or under 8 mm, which represents the critical point for the capacity and the noise. This ensures that the capacity is maintained at a satisfactory level and also prevents noise from increasing. Moreover, a washer group, which comprises at least one each of a resin washer, a rubber washer and a POM (polyoxymethylene) washer is provided between a sensor magnet that is secured to the lower end of the rotating shaft and the lower bearing.
62 Citations
26 Claims
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1. A brushless motor comprising:
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a stator including a stator core and coil winding portions, said stator core having a through hole formed therein; an upper bearing and a lower bearing; an upper bearing holder mounted in said through hole of said stator core, having at least one oil passage hole formed therein and holding said upper bearing; a lower bearing holder mounted in said through hole of said stator core and holding said lower bearing, said lower bearing holder having at least one oil passage hole formed therein in fluid communication with said at least one oil passage hole of said upper bearing holder; a rotary shaft rotatably held by said upper bearing and said lower bearing; a rotor secured to said rotary shaft and including permanent magnets provided along a rotary direction; an upper bearing stopper, provided between said upper bearing and said upper bearing holder, securing said upper bearing to said upper bearing holder, said upper bearing stopper having at least one oil passage hole formed therethrough; a first felt located under said at least one oil passage hole of said upper bearing stopper and contacting said upper bearing; a lower bearing stopper, provided between said lower bearing and said lower bearing holder, securing said lower bearing to said lower bearing holder; a second felt located under said at least one oil passage hole of said lower bearing holder and contacting said lower bearing; and a thrust stopper for axially supporting said rotor, said thrust stopper having a through hole with said rotary shaft mounted therethrough and including a cylindrical portion surrounding said through hole, an oil guide being constituted by a lower surface of said cylindrical portion. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26)
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Specification
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- Resources
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Current AssigneeZexel Valeo Climate Control Corporation (Valeo SE)
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Original AssigneeZexel Corporation
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InventorsHaraguchi, Tatsuo, Gunji, Yoshihide, Takemasa, Masami, Ohsawa, Hiroshi, Umegaki, Fuhito, Ohi, Shinichi
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Primary Examiner(s)Dougherty, Thomas M.
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Assistant Examiner(s)JONES, JUDSON
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Application NumberUS08/711,591Time in Patent Office714 DaysField of Search310/90, 384/136, 384/214, 384/412, 384/413US Class Current310/90CPC Class CodesF16C 23/04 self-adjustingF16C 33/103 retained in or near the bea...F16C 33/74 of sliding-contact bearingsH02K 11/33 Drive circuits, e.g. power ...H02K 21/22 with magnets rotating aroun...H02K 29/08 using magnetic effect devic...H02K 5/10 with arrangements for prote...H02K 5/1675 radially supporting the rot...H02K 5/24 specially adapted for suppr...
