Motor including sensor unit with improved detection

Patent metadata

Field	Value
Publication number	US-10103606-B2
Application number	US-201615146258-A
Country	US
Kind code	B2
Filing date	May 4, 2016
Priority date	May 29, 2015
Publication date	Oct 16, 2018
Grant date	Oct 16, 2018

Abstract

A case includes a cylindrical housing arranged to hold a stator, and having an opening portion at a top thereof; and a motor cover fitted to an upper side of the housing, and arranged to cover an upper side of the stator. A busbar unit includes a sensor busbar electrically connected to a rotation sensor, and a busbar holder arranged at the opening portion to hold the sensor busbar. The case includes a case through hole arranged to open into a space outside of the case. The busbar holder includes a cylindrical holder body portion having at least a portion thereof arranged radially inside of the opening portion; and a protruding portion arranged to protrude out of the case, and having at least a portion thereof arranged in the case through hole. A gap is defined circumferentially between the protruding portion and an edge of the case through hole.

First claim

What is claimed is:

1. A motor comprising:
a rotor comprising a shaft having a central axis extending in a vertical direction as a center thereof;
a bearing arranged to support the shaft;
a stator arranged radially outside of the rotor;
a busbar unit arranged on an upper side of the stator;
a case arranged to accommodate the rotor, the stator, and the busbar unit;
a sensor magnet arranged on the upper side of the stator, and fixed directly or indirectly to the shaft; and
a rotation sensor held by the busbar unit, and arranged axially opposite to the sensor magnet; wherein
the case comprises:
a cylindrical housing arranged to hold the stator, and having an opening portion at a top thereof; and
a motor cover fitted to an upper side of the housing, and arranged to cover the upper side of the stator;

the busbar unit comprises:
a sensor busbar electrically connected to the rotation sensor; and
a busbar holder arranged at the opening portion to hold the sensor busbar;

the case comprises a case through hole arranged to open into a space outside of the case;
the busbar holder comprises:
a cylindrical holder body portion having at least a portion thereof arranged radially inside of the opening portion; and
a protruding portion arranged to protrude out of the case, and having at least a portion thereof arranged in the case through hole; and

a gap is defined circumferentially between the protruding portion and an edge of the case through hole.

2. The motor according to claim 1 , wherein the protruding portion is arranged to project out of the case through the case through hole.

3. The motor according to claim 1 , wherein the protruding portion is a connector portion to which an external power supply is connected.

4. The motor according to claim 3 , wherein
the case through hole is arranged to open radially outwardly;
the connector portion is arranged to project radially outward from the holder body portion; and
the case through hole is arranged in at least one of the housing and the motor cover.

5. The motor according to claim 1 , wherein the busbar holder comprises a bearing holding portion arranged to hold the bearing.

6. The motor according to claim 1 , wherein the case through hole is arranged axially between the motor cover and the housing.

7. The motor according to claim 6 , wherein
the motor cover comprises a cover recessed portion recessed upward from a lower end of the motor cover; and
the cover recessed portion is arranged to define a portion of the case through hole.

8. The motor according to claim 6 , wherein
the housing comprises a housing recessed portion recessed downward from an upper end of the housing; and
the housing recessed portion is arranged to define a portion of the case through hole.

9. The motor according to claim 1 , wherein
the busbar unit comprises a phase busbar electrically connected to the stator;
the busbar holder comprises a holder bottom portion arranged to extend radially inward from an inner circumferential surface of the holder body portion;
the holder bottom portion comprises a bottom portion through hole arranged to pass through the holder bottom portion in an axial direction;
the bottom portion through hole has a connection wire to connect the stator to the phase busbar passed therethrough; and
the bottom portion through hole is arranged to extend in a circumferential direction.

10. The motor according to claim 1 , further comprising an O ring arranged radially between the housing and the holder body portion.

11. The motor according to claim 1 , wherein
the housing comprises a housing flange portion arranged to extend radially;
the motor cover comprises a cover flange portion arranged to extend radially; and
the motor cover and the housing are fixed to each other with an upper surface of the housing flange portion and a lower surface of the cover flange portion being in contact with each other.

12. The motor according to claim 11 , wherein
at least a portion of the case through hole is defined in the housing; and
a lower end of the case through hole is arranged at a level lower than that of the housing flange portion.

13. The motor according to claim 1 , wherein the sensor busbar is arranged to radially overlap with the case through hole.

14. The motor according to claim 1 , further comprising a circuit board held by the busbar unit, wherein the rotation sensor is attached to the circuit board.

Assignees

• Nidec Corp

Inventors

• Yamada Yosuke
• Sato Ryusuke
• Nakahara Yasuaki
• Makino Yusuke
• Fujihara Hisashi

Classifications

• H02K11/215 Primary

  Magnetic effect devices, e.g. Hall-effect or magneto-resistive elements · CPC title

• H02K11/33

  Drive circuits, e.g. power electronics (H02K11/38 takes precedence) · CPC title

• H02K5/225

  Terminal boxes or connection arrangements (specially adapted for submersible motors H02K5/132) · CPC title

• H02K5/04

  Casings or enclosures characterised by the shape, form or construction thereof · CPC title