Motor

Abstract

A motor may include a bearing made of resin for rotatably supporting one end part of the rotor shaft, and an urging member attached to a bearing holder and abutted with a pressurization face of the bearing to urge the bearing toward a side of the rotor shaft. A molding material injection gate trace (projection) which has been used when the bearing is resin-molded is positioned at a center portion of the pressurization face. The molding material injection gate trace may be positioned in a recessed part which is formed at a roughly center portion of the pressurization face of the bearing. Further, the urging member may include an urging piece which is formed by cutting a center portion of a metal plate in a ring shape and an opening part is formed in the urging piece.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will now be described, by way of example only, with reference to the accompanying drawings which are meant to be exemplary, not limiting, and wherein like elements are numbered alike in several Figures, in which:

FIG. 1 is an enlarged cross-sectional view showing a part of a motor in accordance with an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a bearing which is used in a motor in accordance with an embodiment of the present invention.

FIG. 3 is a front view showing a bearing which is used in a motor in accordance with an embodiment of the present invention.

FIG. 4 is an enlarged perspective view showing an urging member which is used in a motor in accordance with an embodiment of the present invention.

FIG. 5 is a front view showing an urging member which is used in a motor in accordance with an embodiment of the present invention.

FIG. 6 is a front view showing a part of an urging member which is used in a motor in accordance with an embodiment of the present invention.

FIG. 7 is a side view showing a motor in accordance with an embodiment of the present invention.

FIG. 8 is a front view showing a motor in accordance with an embodiment of the present invention.

FIG. 9 is an enlarged cross-sectional view showing a part of a conventional motor.

FIG. 10 is a front view showing an urging member used in a conventional motor.

FIG. 11 is a front view showing a bearing used in a conventional motor.

Claims

1. A motor comprising: a rotor having a rotor shaft to which a permanent magnet is fixed;a stator which is formed with a rotor insertion hole into which the rotor is inserted;a bearing holder which is fixed to one end of the stator and is formed with a bearing hole;a bearing made of resin which is provided in the bearing hole for rotatably supporting one end part of the rotor shaft; andan urging member which is attached to the bearing holder and abutted with a pressurization face opposite to a rotor shaft support face of the bearing to urge the bearing toward a side of the rotor shaft;wherein a molding material injection gate trace which has been used when the bearing is resin-molded is positioned at a center portion of the pressurization face.

2. The motor according to claim 1, further comprising a recessed part which is formed at a roughly center portion of the pressurization face so as to concave on a side of the rotor shaft support face, wherein the molding material injection gate trace is positioned in the recessed part.

3. The motor according to claim 2, wherein a depth of the recessed part is set to be in a dimension of that a tip end of the molding material injection gate trace does not protrude from the pressurization face.

4. The motor according to claim 1, wherein the urging member is provided with an urging piece which is formed by a part of a metal plate that is cut and bent, and a tip end portion of the urging piece is abutted with the pressurization face at a portion apart from a recessed part to urge the bearing.

5. The motor according to claim 4, wherein the urging piece is structured by a center portion of the metal plate which is cut and bent in a ring shape and an opening part is formed at a portion of the urging piece where the opening part faces the molding material injection gate trace.

6. The motor according to claim 4, wherein the tip end portion of the urging piece is bent to abut with the pressurization face in a line contact manner.

7. The motor according to claim 1, further comprising a spherical supported face which is provided at an end part of the rotor shaft, and a support recessed part which is formed in the rotor shaft support face of the bearing for engaging with the spherical supported face of the rotor shaft.

8. A motor comprising: a rotor having a rotor shaft to which a permanent magnet is fixed;a stator which is formed with a rotor insertion hole into which the rotor is inserted;a bearing holder which is fixed to one end of the stator and is formed with a bearing hole;a bearing which is provided in the bearing hole for rotatably supporting one end part of the rotor shaft; andan urging member which is attached to the bearing holder and abutted with a pressurization face opposite to a rotor shaft support face of the bearing to urge the bearing toward a side of the rotor shaft;wherein the urging member includes an urging piece which is formed by cutting a center portion of a metal plate in a ring shape and an opening part is formed in the urging piece.

9. The motor according to claim 8, wherein a tip end portion of the urging piece is bent to abut with the pressurization face in a line contact manner and is abutted with the pressurization face at a portion apart from a center of the bearing.

10. The motor according to claim 8, wherein the bearing is made of resin and a molding material injection gate trace which has been used when the bearing is resin-molded is positioned at a center portion of the pressurization face.

11. The motor according to claim 10, further comprising a recessed part which is formed at a roughly center portion of the pressurization face so as to concave on a side of the rotor shaft support face, wherein the molding material injection gate trace is positioned in the recessed part.

12. The motor according to claim 11, wherein a depth of the recessed part is set to be in a dimension of that a tip end of the molding material injection gate trace does not protrude from the pressurization face.

13. The motor according to claim 11, wherein a tip end portion of the urging piece is abutted with the pressurization face at a portion apart from the recessed part to urge the bearing.

14. The motor according to claim 10, wherein the opening part of the urging piece is formed at a position where the opening part faces the molding material injection gate trace.

15. The motor according to claim 8, further comprising a spherical shaped supported face which is provided in the one end part of the rotor shaft, and a support recessed part which is formed in the rotor shaft support face of the bearing for engaging with the spherical shaped supported face.

16. The motor according to claim 8, wherein a tip end side from the opening part which is formed at a center portion of the urging piece is formed as an abutting part for abutting with the pressurization face of the bearing.

17. The motor according to claim 16, wherein an abutting width of the abutting part of the urging piece with the pressurization face of the bearing is larger than a width of a root part on a root side from the opening part of the urging piece.