Patent Application
20190238009
The present application claims the benefit of priority of Japanese Patent Application No, 2018-014095, filed on Jan. 30, 2018, the content of which is incorporated herein by reference.
The present invention relates to a stator for a rotary electric machine.
A stator for a rotary electric machine is constituted by winding a coil around a stator core. The stator is generally cooled by a coolant because the temperature of the stator rises when the rotary electric machine operates. As illustrated in
For this reason, a proposal has been proposed in which a stator housing is divided into two parts and a water jacket is formed by combining the two parts. Specifically, as illustrated in
However, in the rotary electric machine of the related art illustrated in
An object of the invention is to provide a stator for a rotary electric machine which has excellent productivity and high cooling performance.
According to a stator for a rotary electric machine including: a stator core; and a housing for accommodating the stator core, wherein: an outer circumferential surface of the stator core is covered with a coating portion having non-water permeability; a pair of sealing portions are provided between the coating portion and an inner circumferential surface of the housing and on both end sides in an axial direction; and a coolant flow path is formed by the coating portion, the inner circumferential surface of the housing, and the pair of sealing portions.
According to the present invention, since a coolant flow path is formed by a coating portion which has non-water permeability and covers the outer circumferential surface of a stator core, the inner circumferential surface of a housing, and a pair of sealing portions, it is possible to properly cool the stator core from the outer circumferential side thereof. Further, since a core structure of the housing is not necessary at the time of manufacturing and the stator core does not need to be shrink-fitted to the stator holder, productivity can be improved. Also, since it is sufficient as long as the housing satisfies the press-fitting strength against the pair of sealing portions, the thickness of the housing or the stator holder can be made thinner as compared with a case where the outer circumferential surface of the stator core is press-fitted by contacting with the inner circumferential surface of the housing or the inner circumferential surface of the stator holder. Therefore, the cooling performance is improved.
Hereinafter, a stator for a rotary electric machine according to an embodiment of the present invention will be described with reference to the drawings.
As illustrated in
The housing 14 is a bottomed cylindrical member and includes a cylindrical portion 14a, an outward flange portion 14b extending radially outward from an end portion of the cylindrical portion 14a on one end side, and a bottom portion 14c extending radially inward from an end portion of the cylindrical portion 14a on the other end side.
The stator core 11 is constituted by laminating a plurality of steel plates 21 having an annular shape in an axial direction and an outer circumferential surface 11a thereof is covered with a coating portion 18 having non-water permeability. The coating portion 18 is made of a resin or rubber and is molded on the outer circumferential surface 11a of the stator core 11. In the axial direction, coil ends of the coil 12 protrude from one end surface 11 b and the other end surface 1 is of the stator core 11.
The sealing portions 16 are, for example, O-rings and arranged at both end portions of the coating portion 18 covering the outer circumferential surface 11a of the stator core 11 in the axial direction to seal a portion between the coating portion 18 covering the outer circumferential surface 11a of the stator core 11 and an inner circumferential surface 19 of the cylindrical portion 14a of the housing 14. The stator core is press-fitted to the inner circumferential surface 19 of the housing 14 in a state where the pair of sealing portions 16 are attached to the coating portion 18 by adhesion or the like.
In the stator 10 for the rotary electric machine constituted as described above, a water jacket WJ is formed on an outer circumferential side of the stator core 11 by the coating portion 18, the inner circumferential surface 19 of the housing 14, and the pair of sealing portions 16. Therefore, the stator core 11 is cooled from the outer circumferential side thereof by supplying a coolant (for example, cooling water, cooling oil, and ATF) to the water jacket WJ from a coolant supply portion (not illustrated).
Further, since the stator core 11 is press-fitted to the inner circumferential surface 19 of the housing 14 in a state where the pair of sealing portions 16 are attached to the outer circumferential surface 11a of the stator core 11 by adhesion or the like, a core structure of a housing is not necessary at the time of manufacturing as in a case of the related art. Since it is not necessary to shrink-fit a stator core to a stator holder, productivity can be improved.
Further, since it is sufficient as long as the housing 14 satisfies the press-fitting strength against the pair of sealing portions 16, the thickness of the housing 14 can be made thinner as compared with a case where the outer circumferential surface 11a of the stator core 11 is press-fitted by contacting with the inner circumferential surface 19 of the housing 14. Therefore, the cooling performance is improved.
Also, the coating portion 18 is made of a resin or rubber and molded on the outer circumferential surface 11a of the stator core 11. Therefore, the thickness of the coating portion 18 can be made thin and it is possible to reliably prevent the coolant from permeating into the stator core 11.
Further, in the stator 10 for the rotary electric machine illustrated in
In this way, the number of parts can be reduced by using the sealing integral coating portion 18A and it is not necessary to perform positioning between the coating portion 18 and the pair of sealing portions 16.
As illustrated in
The invention is not limited to the embodiment described above, and appropriate modifications, improvement, or the like can be made.
At least the following matters are described in this specification. Although the corresponding constituent elements and the likes in the embodiments described above are described in parentheses, the present invention is not limited thereto.
(1) A stator (stator 10) for a rotary electric machine including:
a stator core (stator core 11); and
a housing (housing 14) for accommodating the stator core, in which
an outer circumferential surface (outer circumferential surface 11a) of the stator core is covered with a coating portion (coating portion 18 and sealing integral coating portion 18A) having non-water permeability,
a pair of sealing portions (sealing portions 16 and sealing portions 36) are provided between the coating portion and an inner circumferential surface (inner circumferential surface 19) of the housing and on both end sides in an axial direction, and
a coolant flow path (water jacket WJ) is formed by the coating portion, the inner circumferential surface of the housing, and the pair of sealing portions.
According to (1), since the coolant flow path is formed by the coating portion which has non-water permeability and covers the outer circumferential surface of the stator core, the inner circumferential surface of the housing, and the pair of sealing portions, it is possible to properly cool the stator core from the outer circumferential side thereof. Further, since a core structure of the housing is not necessary and the stator core does not need to be shrink-fitted to the stator holder, productivity can be improved. Also, since it is sufficient as long as the housing satisfies the press-fitting strength against the pair of sealing portions, the thickness of the housing or the stator holder can be made thinner as compared with a case where the outer circumferential surface of the stator core is press-fitted by contacting with the inner circumferential surface of the housing or the inner circumferential surface of the stator holder. Therefore, the cooling performance is improved.
(2) The stator for a rotary electric machine according to (1), in which the coating portion is made of a resin or rubber and is molded on the outer circumferential surface of the stator core.
According to (2), since the coating portion made of a resin or rubber is molded on the outer circumferential surface of the stator core, the thickness of the coating portion can be made thinner and it is possible to reliably prevent the coolant from permeating into the stator core.
(3) The stator for a rotary electric machine according to (1) or (2), in which the coating portion and the pair of sealing portions are integrally molded.
According to (3), since the coating portion and the pair of sealing portion are integrally molded, the number of parts can be reduced and it is not necessary to perform positioning between the coating portion and the pair of sealing portions.
(4) The stator for a rotary electric machine according to (3), in which the coating portion includes a protrusion portion (protrusion portion 39) which protrudes from the outer circumferential surface between the pair of sealing portions in the axial direction.
According to (4), since the coating portion includes the protrusion portion protruding from the outer circumferential surface between the pair of sealing portions, the surface area increases thereby increasing the cooling efficiency.
(5) The stator for a rotary electric machine according to (4), in which a flow path (flow path 40) of a spiral shape is formed in the coolant flow path by the protrusion portion.
According to (5), since the flow path of a spiral shape is formed in the coolant flow path by the protrusion portion, the flow of the coolant is regulated, and thus the coolant can be properly induced.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2018-014095 | Jan 2018 | JP | national |
