External rotor motor with integrated bearing housing and box for control electronics

Patent metadata

Field	Value
Publication number	US-10605248-B2
Application number	US-201113577258-A
Country	US
Kind code	B2
Filing date	Feb 25, 2011
Priority date	Mar 15, 2010
Publication date	Mar 31, 2020
Grant date	Mar 31, 2020

Abstract

A fan has an electronically commutated external-rotor motor serving to drive it. The motor has an internal stator (20) having a stator lamination stack (64) and a winding arrangement (66; 164, 166, 168, 170) associated with the stack. The internal stator has a central opening (149) for journaling a shaft (42). The fan further has a permanent-magnet rotor (28) separated from the internal stator (20) by a magnetically effective air gap (99). The internal stator (20) has a plastic coating (56, 58) that surrounds the stator windings, forms a bearing tube for journaling the shaft (42), and defines a wall element (62), implemented integrally with the plastic coating (56, 58), forming a compartment or cavity (108) for electrical components (112) of the motor. The plastic coating, bearing tube and compartment are preferably molded in a single working step.

First claim

What is claimed is:

1. A fan driven by an electronically commutated external-rotor motor, wherein said motor comprises:
an internal stator ( 20 ) having a stator lamination stack ( 64 );
a permanent-magnet rotor ( 28 ) having a shaft ( 42 ) and bearings ( 48 , 50 );
a slot insulator ( 104 ) and a winding arrangement ( 66 ; 164 , 166 , 168 , 170 ), the winding arrangement ( 66 ; 164 , 166 , 168 , 170 ) being associated with said stator lamination stack, wherein the internal stator is configured with a central opening ( 149 ) to receive the shaft ( 42 ) and said bearings ( 48 , 50 ) of the rotor;
said permanent-magnet rotor ( 28 ) separated from the internal stator ( 20 ) by a magnetically effective air gap ( 99 ), wherein the rotor ( 28 ) is equipped on an outer side thereof with fan blades ( 32 );
said slot insulator ( 104 ) serving as a coil former for the winding arrangement ( 66 ; 164 , 166 , 168 , 170 ) and having a plurality of projections ( 162 );
a plurality of electrical connector pins ( 106 ), each secured in a respective one of said projections ( 162 ) and having a respective end of a wire ( 154 ) of the winding arrangement electrically and mechanically connected to a respective one of said pins;
a plastic overmold ( 56 , 58 ) of the internal stator ( 20 ) extending on all sides of the internal stator ( 20 ) and forming, in the central opening ( 149 ) of the internal stator ( 20 ), a bearing tube configured to receive therein said bearings ( 48 , 50 ) of the rotor ( 28 ) for journaling the shaft ( 42 ) and a cylindrical spacing member ( 52 ) axially interposed between said bearings ( 48 , 50 ) of the rotor, said bearing tube having a first end, adjacent to said rotor ( 28 ) and a second, closed end ( 70 ) remote from the rotor ( 28 );
the plastic overmold of the internal stator ( 20 ) forming a casing ( 62 ) having a wall element ( 109 ) and defining a cavity ( 108 ) for reception of electrical components ( 112 ) of the motor, which wall element is provided on a side of the stator lamination stack ( 64 ) facing away from the closed end ( 70 ) of the bearing tube formed in the stator;
the plastic overmold of the internal stator ( 20 ) being in contact with the projections, the projections ( 162 ) thereby each being partly in contact with the wall element formed by the plastic overmold of the internal stator ( 20 ) and partly projecting out of the wall element into said cavity ( 108 );
said electrical connector pins ( 106 ) projecting out of the respective projections ( 162 ) into the cavity ( 108 ); and
the plastic overmold of the internal stator ( 20 ) forming a fan housing ( 24 ) which is connected integrally, by means of connecting elements ( 134 , 136 ), to the wall element ( 62 ) of the cavity ( 108 ), and which forms, together with the rotor ( 28 ), an air passage conduit ( 142 ) into which the fan blades ( 32 ) project.

2. The fan according to claim 1 , wherein the bearing tube is equipped on an inner side with longitudinal ribs ( 58 ).

3. The fan according to claim 2 , wherein an enveloping curve, defined by the inner ends of the longitudinal ribs ( 58 ), has, at least in part, a circular cross section.

4. The fan according to claim 1 , wherein
the bearing tube ( 56 , 58 ) is formed, at the first end, with a collar ( 60 ), in which is secured a holding member ( 96 ) that retains a bearing of the bearings ( 48 , 50 ) in the bearing tube ( 56 , 58 ).

5. The fan according to claim 4 , wherein the holding member ( 96 ) has a claw edge ( 98 ) that points toward the rotor ( 28 ) and provides a hooking engagement with the inside of the collar ( 60 ) of the bearing tube ( 56 , 58 ), thereby axially clamping at least one of said bearings ( 48 , 50 ).

6. The fan according to claim 1 , wherein the bearings ( 48 , 50 ) are arranged at a distance from one another in the bearing tube ( 56 , 58 ), namely said bearing ( 48 ) mounted at an end of the bearing tube, and said bearing ( 50 ) mounted at the other end of the bearing tube, and wherein an outer ring of said bearing ( 50 ) engages an end face of a shoulder ( 92 ) formed in the bearing tube ( 56 , 58 ), and said outer ring is braced with another side, via said cylindrical spacing member ( 52 ), against an oppositely located shoulder of an outer ring of the bearing ( 48 ), which outer ring is, in turn, retained in the bearing tube by said holding member ( 96 ).

7. The fan according to claim 1 , wherein the rotor ( 28 ) comprises a hub ( 40 ) that is equipped, on a side facing toward the internal stator ( 20 ), with an axial projection ( 80 ) that is configured for abutment against an inner ring of an adjacent one of said bearings ( 48 , 50 ), in order to enable said adjacent bearing to be pressed into the bearing tube ( 56 , 58 ) by axial pressure on the rotor ( 28 ), the axial projection ( 80 ) being configured not to abut against an outer ring of said adjacent bearing.

8. The fan according to claim 7 , further comprising
a spring ( 78 ) coaxial with the shaft ( 42 ) of the rotor ( 28 ) and serving to apply a spring force, in order to urge said bearing ( 48 , 50 ) toward one another.

9. The fan according to claim 1 , wherein the wire ( 154 ) is, on its course from the pin to the winding, leaving the respective pin, on the side of the corresponding projection, projecting out of the wall element into said cavity.

10. The fan according to claim 9 , wherein the cover ( 126 ; 127 ) is connected by an adhesive joint to a housing part ( 109 ) that serves for reception of the electrical components ( 112 ) of the motor.

11. The fan according to claim 9 , wherein the cover ( 126 ; 127 ) is connected by a mechanical seal connection to a housing part ( 109 ) that serves for reception of the electrical components ( 112 ).

12. The fan according to claim 1 , wherein said plastic overmold ( 56 , 58 ) is composed of a polyamide material.

13. The fan according to claim 1 , wherein the plastic overmold is composed of a PBT plastic material.

14. The fan according to claim 1 , wherein the plastic overmold is composed of a fiber-reinforced plastic.

15. The fan according to claim 1 , wherein the plastic overmold ( 56 , 58 ) at least partly covers a central opening ( 149 ) of the internal stator ( 20 ).

16. The fan according to claim 1 , wherein the plastic overmold forms, at least in part, an electrical insulator ( 62 ) for a part of the internal stator ( 20 ) which adjoins a magnetically effective air gap ( 99 ) of the motor.

17. The fan according to claim 1 , wherein the winding arrangement ( 66 ; 164 , 166 , 168 , 170 ) further comprises said electrical connector pins ( 106 ) which project away from the plastic overmold of the internal stator ( 20 ), in a direction toward a cavity ( 108 ) that is formed on a side of the internal stator ( 20 ) facing away from the rotor ( 28 ).

18. The fan according to claim 1 , wherein the internal stator ( 20 ) is configured with cavities, said cavities being subsequently filled up by said plastic overmold ( 56 , 58 ).

19. The fan according to claim 1 , wherein said wire ( 154 ) of the winding arrangement is at least partly electrically and mechanically connected to the respective pin and to the winding arrangement ( 66 ; 164 , 166 , 168 , 170 ) inside said respective projection ( 162 ),
the wire ( 154 ) entering the inside of the projection ( 162 ) at an end of the projection which projects out of the wall element into said cavity ( 108 ) for reception of said electrical components ( 112 ) of the motor.

2

Assignees

• Wagner Thomas
• Rojo Francisco
• Ebm Papst St Georgen Gmbh & Co Kg

Inventors

• Wagner Thomas
• Rojo Francisco

Classifications

• F04D29/059

  Roller bearings · CPC title

• F04D29/0563

  Bearings cartridges · CPC title

• F04D25/0693

  Details or arrangements of the wiring · CPC title

• F04D25/062 Primary

  Details of the bearings · CPC title

• H02K3/521

  applicable to stators only · CPC title