COOLED ROTARY ELECTRIC MACHINE

Abstract

A cooling system for a rotary electric machine having an axis of rotation includes a cooling jacket suitable for receiving a stator of the rotary electrical machine, a housing receiving the cooling jacket, in which an outer wall of the cooling jacket forms, with an inner wall of the housing, a cooling chamber through which a cooling fluid can flow. A separator element separates an inlet zone of the cooling chamber and an outlet zone of the cooling chamber. The separator element includes a fastening part, of a first length, fastened to the outer wall of the cooling jacket or the inner wall of the housing, a first separating part, of a second length, inclined relative to the fastening part and non-parallel to the fastening part. The first length is less than the second length such that the first separating part includes comprises a first free end that is not directly connected to the fastening part. The invention also relates to an electric machine equipped with such a cooling system.

Claims

1. A cooling system for a rotary electric machine having an axis of rotation, comprising: a cooling jacket that is able to receive a stator of the rotary electric machine, a housing receiving the cooling jacket, wherein an outer wall of the cooling jacket forms, together with an inner wall of the housing, a cooling chamber that is able to be passed through by a cooling fluid, and wherein the housing comprises an inlet opening for the inlet of the cooling fluid into an inlet zone of the cooling chamber, and an outlet opening for the outlet of the cooling fluid from an outlet zone of the cooling chamber, the inlet opening and the outlet opening being formed in the housing, and wherein a separating element, which is separate from the cooling jacket and from the housing, is fixed to one of the outer wall of the cooling jacket and the inner wall of the housing in order to separate the inlet zone of the cooling chamber and the outlet zone of the cooling chamber, the separating element comprising: aa fixing part, with a first length, having a fixing face with a shape that is complementary to the shape of the one of the outer wall of the cooling jacket and the inner wall of the housing to which the separating element is fixed, a first separation part, with a second length, that is inclined with respect to the fixing part and not parallel to the fixing part, the first length being smaller than the second length such that the first separation part comprises a first free end which is not directly connected to the fixing part.

2. The cooling system as claimed in claim 1, wherein the first separation part forms an angle of between 20 degrees and 160 degrees, in particular between 45 degrees and 135 degrees, with the fixing part.

3. The cooling system as claimed in claim 1, wherein the first separation part is formed in continuity of material with the fixing part beyond a first bending zone.

4. The cooling system as claimed in claim 1, wherein the cooling chamber has a shape exhibiting symmetry of revolution whose axis is the axis of rotation, the shape exhibiting symmetry of revolution having a first thickness measured at a first axial end and a second thickness measured at a second axial end, the first thickness being smaller than the second thickness, and wherein the first free end is oriented toward the first axial end, another end of the first separation part that is opposite to the free end being oriented toward the second axial end.

5. The cooling system as claimed in claim 4, wherein the separating element is made from a sheet material, in particular of sheet steel.

6. The cooling system as claimed in claim 5, wherein an edge surface of the sheet material of the first free end faces toward the one of the outer wall of the cooling jacket and the inner wall of the housing to which the separating element is fixed.

7. The cooling system as claimed in claim 1, wherein the separating element comprises a second separation part, with a third length, that is inclined with respect to the fixing part and not parallel to the fixing part, the first length being smaller than the third length such that the second separation part comprises a second free end that is not directly connected to the fixing part.

8. The cooling system as claimed in claim 7, wherein the second separation part is formed in continuity of material with the fixing part beyond a second bending zone.

9. The cooling system as claimed in claim 1, wherein the separating element is welded to one of the outer wall of the cooling jacket and the inner wall of the housing.

10. An electric machine comprising: a stator, a rotor, a cooling system as claimed in claim 1.

11. The electric machine as claimed in claim 10, wherein the stator is mounted by force in the cooling jacket.

12. The cooling system as claimed in claim 2, wherein the first separation part is formed in continuity of material with the fixing part beyond a first bending zone.

13. The cooling system as claimed in claim 2, wherein the cooling chamber has a shape exhibiting symmetry of revolution whose axis is the axis of rotation, the shape exhibiting symmetry of revolution having a first thickness measured at a first axial end and a second thickness measured at a second axial end, the first thickness being smaller than the second thickness, and wherein the first free end is oriented toward the first axial end, another end of the first separation part that is opposite to the free end being oriented toward the second axial end.

14. The cooling system as claimed in claim 2, wherein the separating element comprises a second separation part, with a third length, that is inclined with respect to the fixing part and not parallel to the fixing part, the first length being smaller than the third length such that the second separation part comprises a second free end that is not directly connected to the fixing part.

15. The cooling system as claimed in claim 2, wherein the separating element is welded to one of the outer wall of the cooling jacket and the inner wall of the housing.

16. An electric machine comprising: a stator, a rotor, a cooling system as claimed in claim 2.

17. The cooling system as claimed in claim 3, wherein the cooling chamber has a shape exhibiting symmetry of revolution whose axis is the axis of rotation, the shape exhibiting symmetry of revolution having a first thickness measured at a first axial end and a second thickness measured at a second axial end, the first thickness being smaller than the second thickness, and wherein the first free end is oriented toward the first axial end, another end of the first separation part that is opposite to the free end being oriented toward the second axial end.

18. The cooling system as claimed in claim 3, wherein the separating element comprises a second separation part, with a third length, that is inclined with respect to the fixing part and not parallel to the fixing part, the first length being smaller than the third length such that the second separation part comprises a second free end that is not directly connected to the fixing part.

19. The cooling system as claimed in claim 3, wherein the separating element is welded to one of the outer wall of the cooling jacket and the inner wall of the housing.

20. An electric machine comprising: a stator, a rotor, a cooling system as claimed in claim 3.

Description

[0045] The invention may be understood better upon reading the following description of nonlimiting implementation examples thereof and upon studying the appended drawing, in which:

[0046] FIG. 1 depicts a partial view of a rotary electric machine comprising a cooling system according to the invention,

[0047] FIG. 2 depicts a partial cross-sectional view of the cooling system of the rotary electric machine in FIG. 1 according to a first embodiment,

[0048] FIG. 3 depicts another partial cross-sectional view of the cooling system of the rotary electric machine in FIG. 1 according to the first embodiment,

[0049] FIG. 4 depicts another partial cross-sectional view of the cooling system of the rotary electric machine in FIG. 1 according to the first embodiment,

[0050] FIG. 5 depicts a partial view of the cooling system of the rotary electric machine in FIG. 1 according to the first embodiment,

[0051] FIG. 6 depicts a view of a separating element of the cooling system of the rotary electric machine in FIG. 1 according to the first embodiment,

[0052] FIG. 7 depicts a view of a separating element of the cooling system of the rotary electric machine in FIG. 1 according to a second embodiment.

[0053] Throughout the figures, elements that are identical or perform the same function bear the same reference numbers. The following embodiments are examples. Although the description refers to one or more embodiments, this does not necessarily mean that each reference relates to the same embodiment, or that the features apply only to one embodiment. Individual features of different embodiments may also be combined or interchanged to provide other embodiments.

[0054] FIG. 1 and FIG. 2 depict partial views of a rotary electric machine of axis of rotation A comprising a stator, a rotor and a cooling system according to the invention.

[0055] To make the figures clearer, certain elements of the rotary electric machine have not been depicted in the figures. In particular, the rotor and the stator have not been depicted.

[0056] The cooling system comprises: [0057] a cooling jacket 3 that is able to receive a stator of the rotary electric machine 1, [0058] a housing 2 receiving the cooling jacket.

[0059] The cooling jacket is, for example, a cylindrical steel sleeve.

[0060] The stator is, for example, mounted by force in the cooling jacket 3.

[0061] An outer wall 11 of the cooling jacket 3 forms, together with an inner wall 10 of the housing, a cooling chamber 6.

[0062] FIG. 3 depicts a partial view of the rotary electric machine comprising the cooling system according to the invention. A cross section makes it possible to see the cooling chamber.

[0063] A cooling fluid circulates in the cooling chamber 6. The housing comprises an inlet opening 4 for the inlet of the cooling fluid into an inlet zone 7 of the cooling chamber 6, and an outlet opening 5 for the outlet of the cooling fluid from an outlet zone 8 of the cooling chamber 6.

[0064] The inlet opening 4 and the outlet opening 5 are formed in the housing 2. In the embodiments depicted in the figures, chimneys formed in continuity of material with the housing allow the inflow to the inlet opening 4 and the outlet of the fluid after the outlet opening 5. In another embodiment of the invention, the chimneys are added components, for example tubes force-fitted into the inlet opening 4 and the outlet opening 5.

[0065] The cooling system further comprises a separating element 9, which is separate from the cooling jacket 3 and from the housing 2. The separating element 9 is fixed to one of the outer wall 11 of the cooling jacket 3 and the inner wall 10 of the housing 2. The separating element 9 separates the inlet zone 7 of the cooling chamber 6 and the outlet zone 8 of the cooling chamber 6.

[0066] This separation between the inlet zone 7 of the cooling chamber 6 and the outlet zone 8 of the cooling chamber 6 prevents an excessively large quantity of cooling fluid from circulating via the shortest path between the inlet opening 4 and the outlet opening 5. The separation promotes the circulation of the fluid into the cooling chamber via the longest path so as to improve the exchanges of heat between the cooling fluid and the cooling jacket 3 which is in thermal contact with the stator.

[0067] FIG. 4 depicts the separating element 9 in its environment.

[0068] The separating element 9 comprises: [0069] a fixing part 12, with a first length 13, having a fixing face with a shape that is complementary to the shape of the one of the outer wall 11 of the cooling jacket 3 and the inner wall 10 of the housing 2 to which the separating element 9 is fixed, [0070] a first separation part 14, with a second length 15, that is inclined with respect to the fixing part 12 and not parallel to the fixing part 12.

[0071] The first length 13 is smaller than the second length 15 such that the first separation part 14 comprises a first free end 16 which is not directly connected to the fixing part 12.

[0072] FIG. 6 depicts the separating element 9 of the cooling system according to a first embodiment.

[0073] The fixing part 12 is therefore shorter than the first separation part 14. The first separation part 14 further comprises a first intermediate part 27 which is directly connected to the fixing part 12. The first free end 16 is directly connected to the first intermediate part 27. The first intermediate part 27 therefore provides the connection between the fixing part 12 and the first free end 16.

[0074] The first separation part 14 is, for example, formed in continuity of material with the fixing part 12 beyond a first bending zone 17. The first bending zone 17 therefore provides the direct connection between the fixing part 12 and the first intermediate part 27 of the first separation part 14.

[0075] The first separation part 14 may form an angle of between 20 degrees and 160 degrees, in particular between 45 degrees and 135 degrees, with the fixing part 12.

[0076] In the embodiments of the invention depicted in the figures, the first separation part 14 forms an angle of 90 degrees with the fixing part 12.

[0077] The cooling chamber 6 has, for example, a shape exhibiting symmetry of revolution whose axis is the axis of rotation A. The shape exhibiting symmetry of revolution has a first thickness 18, measured at a first axial end 20, and a second thickness 19, measured at a second axial end 21. The first thickness 18 is smaller than the second thickness 19. The first free end 16 is oriented toward the first axial end 20.

[0078] Another end 22 of the first separation part 14 that is opposite to the free end 16 is oriented toward the second axial end 21. The other end may form part of the first intermediate part 27.

[0079] The separating element 9 is, for example, made from a sheet material, in particular of sheet steel.

[0080] The fixing part 12 of the separating element 9 is, for example, welded to the one of the outer wall 11 of the cooling jacket 3 and the inner wall 10 of the housing 2 to which the separating element 9 is fixed.

[0081] In the embodiments depicted in the figures, the fixing part 12 has been welded to the outer wall 11 of the cooling jacket 3. FIG. 5 depicts the separating element 9 of the first embodiment of the cooling system, welded to the outer wall 11 of the cooling jacket.

[0082] In other embodiments of the invention, other types of fixing may be used, in particular adhesive bonding, brazing or clinching.

[0083] An edge surface 22 of the sheet material of the first free end 16 may face toward the one of the outer wall 11 of the cooling jacket 3 and the inner wall 10 of the housing 2 to which the separating element 9 is fixed. The separating element 9 is, for example, press-cut or cut by laser cutting. The edge surface 22 forms part of the cut surface of the sheet material.

[0084] The edge surface 22 may be in contact with the one of the outer wall 11 of the cooling jacket 3 and the inner wall 10 of the housing 2 to which the separating element 9 is fixed.

[0085] To facilitate the bending and to avoid tearing of the sheet material during the bending between the first separation part 14 and the first intermediate part 27, a first notch 30 may be produced between the first intermediate part 27 and the first free end 16. Such a first notch 30 makes it possible to produce a separating element 9 whose edge surface 22 is close to or in contact with the one of the outer wall 11 of the cooling jacket 3 and the inner wall 10 of the housing 2 to which the separating element 9 is fixed.

[0086] FIG. 7 depicts the separating element 9 of the cooling system according to a second embodiment.

[0087] The second embodiment of the cooling system according to the invention differs from the first embodiment by its separating element 29. This separating element is similar to the separating element 9 of the first embodiment but it further comprises a second separation part 23, with a third length 24, that is inclined with respect to the fixing part face 12 and not parallel to the fixing part face 12. The first length 13 is smaller than the third length 24 such that the second separation part 23 comprises a second free end 25 which is not directly connected to the fixing part 12.

[0088] The fixing part 12 is therefore shorter than the second separation part 23. The second separation part 23 further comprises a second intermediate part 28 which is directly connected to the fixing part 12. The second free end 25 is directly connected to the second intermediate part 28. The second intermediate part 28 therefore provides the connection between the fixing part 12 and the second free end 25.

[0089] The second separation part 23 is, for example, formed in continuity of material with the fixing part 12 beyond a second bending zone 26. The second bending zone 26 therefore provides the direct connection between the fixing part 12 and the second intermediate part 28 of the second separation part 23.

[0090] The second separation part 23 may form an angle of between 20 degrees and 160 degrees, in particular between 45 degrees and 135 degrees, with the fixing part 12. The separating element 29 of the second embodiment of the invention has a second separation part 23 which forms an angle of 90 degrees with the fixing part 12.

[0091] As in the case of the first separation part 14, a second notch 31 may be produced between the second intermediate part 28 and the second free end 25 of the second separation part 23.

[0092] In the two embodiments of the invention depicted in the figures, the separation part(s) 14, 23 are planar. In other embodiments of the invention that are not depicted, the separation part(s) 14, 23 are not planar. In another embodiment that is not depicted, the separation part(s) may have an opening or an indentation to allow limited passage of the cooling fluid between the inlet zone of the cooling chamber and the outlet zone of the cooling chamber through the separating element.