Water jacket and method of manufacturing the water jacket

Abstract

To provide a water jacket capable of improving cooling efficiency of a heating unit.SOLUTION: In a water jacket having a coolant flow path inside a housing arranged on an outer periphery of a heating unit, the coolant flow path has: a plurality of main flow path pipe parts arranged in the vicinity of the outer periphery of the heating unit, extending linearly, and arrayed along the outer periphery of the heating unit; an inflow-side collective pipe part that collectively connects the upstream end parts of the main flow path pipe parts, and causes a coolant to flow into the main flow path pipe parts; and an outflow-side collective pipe part that collectively connects the downstream end parts of the main flow path pipe parts, and causes the coolant to flow out from the main flow path pipe parts. Each of the main flow path pipe parts has a vortex generation unit that generates a vortex in the vicinity of the inner upstream end part.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a water jacket and a method for manufacturing a water jacket. [Background technology]

[0002] Conventionally, a water jacket provided on the peripheral surface of a stator housing of an electric motor is known (see, for example, Patent Document 1). This water jacket is provided with a turbulence generating member at the coolant inlet to the coolant jacket. The turbulence generating member generates turbulence in the coolant flowing toward the coolant jacket, and causes the coolant to flow into the coolant jacket approximately evenly, thereby improving cooling efficiency. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2002-119019 Summary of the Invention [Problem to be solved by the invention]

[0004] In the water jacket of the above-mentioned conventional technology, the wide coolant jacket extends around the circumferential direction of the stator housing, which is a heat-generating part. Therefore, even if turbulence is generated in the coolant flowing into the coolant jacket by the turbulence generating member, the effect of the turbulence is reduced as the coolant flows through the flow path of the coolant jacket, which is curved around the circumferential direction of the stator housing. Therefore, there is room for improvement in terms of efficient cooling throughout the entire coolant jacket.

[0005] An object of the present invention is to provide a water jacket that can further improve the cooling efficiency of a heat-generating portion, and a method for manufacturing such a water jacket. [Means for solving the problem]

[0006] (1) The water jacket according to the present invention is a water jacket (for example, the water jacket 1 described later) having a coolant flow path (for example, the coolant flow path 3 described later) inside a housing (for example, the housing 2 described later) arranged on the outer periphery of a heat generating part (for example, the stator core 101 described later), and the coolant flow path is arranged near the outer periphery of the heat generating part, and includes a main flow path pipe section (for example, the main flow path pipe section 31 described later) that extends linearly and is arranged along the outer periphery of the heat generating part, and a plurality of main flow path pipe sections (for example, the main flow path pipe section 31 described later) above the main flow path pipe section. The main flow path pipe has an inlet-side collecting pipe section (for example, an inlet-side collecting pipe section 32 described later) that connects together the downstream ends (for example, an upstream end section 31a described later) of the main flow path pipe sections and allows the coolant to flow into the main flow path pipe section, and an outlet-side collecting pipe section (for example, an outlet-side collecting pipe section 33 described later) that connects together the downstream ends (for example, downstream end sections 31b described later) of the main flow path pipe sections and allows the coolant to flow out of the main flow path pipe section, and each of the main flow path pipe sections has a vortex generating section (for example, a vortex generating section 4 described later) that generates a vortex flow near the upstream end inside.

[0007] (2) In the water jacket described in (1) above, the vortex generating section may have a plurality of deflection plates (e.g., deflection plate 41 described later) that deflect the flow of coolant inside the main flow path pipe section in the same circumferential direction of the main flow path pipe section (e.g., direction D4 described later).

[0008] (3) In the water jacket described in (2) above, the deflection plates may be integrally provided on an inner wall surface of the main flow path pipe portion (for example, an inner wall surface 31c described below).

[0009] (4) In the method for manufacturing a water jacket according to the present invention, the water jacket according to any one of (1) to (3) above is integrally molded by additive manufacturing using a metal material. [Effects of the Invention]

[0010] According to (1) above, the vortex generating section can generate a vortex within the main flow path pipe section that extends linearly in the coolant flow path, thereby improving the heat transferability of the coolant flow path and further improving the cooling efficiency of the heat-generating section.

[0011] According to the above (2), a vortex can be easily generated in the main flow path pipe section by the plurality of deflection plates in the main flow path pipe section.

[0012] According to the above feature (3), the deflection plates extending from the inner wall surface of the main flow path pipe section can generate vortex flows more efficiently within the main flow path pipe section.

[0013] According to the above (4), a water jacket that can further improve the cooling efficiency of heat-generating parts can be easily manufactured using a 3D printer. The vortex generated by the vortex generator in the main flow path pipe also improves the removability of metal material remaining in the coolant flow path after molding. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a vertical cross-sectional view showing an electric motor equipped with a water jacket according to an embodiment of the present invention. [Figure 2] FIG. 2 is a perspective view showing only the coolant liquid flow paths in the water jacket according to the embodiment. [Figure 3] 2 is a perspective view showing a partly cutaway vortex generating section in a main flow path pipe section at part A in FIG. 1. FIG. [Figure 4] FIG. 2 is a perspective view showing only the vortex generating section according to the embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. Fig. 1 shows an electric motor 100 equipped with a water jacket 1 according to this embodiment. The direction D1 indicated by the arrow in Fig. 1 is the axial direction of the electric motor 100, and the direction D2 is the radial direction of the electric motor 100.

[0016] The electric motor 100 has a substantially cylindrical stator core 101 extending in the axial direction, and a rotor 102 rotatably supported in an axial hole 101a of the stator core 101. The stator core 101 is made of an iron-based metal material, and houses coils 103 in a plurality of slots 101b.

[0017] When the electric motor 100 is driven, heat from the coil 103 is transferred to the stator core 101, causing the stator core 101 to generate heat. The water jacket 1 cools the coil 103 through the stator core 101. In this embodiment, the stator core 101 is a heat-generating part to be cooled by the water jacket 1.

[0018] The water jacket 1 is disposed radially outside the stator core 101 of the electric motor 100. The water jacket 1 has a housing 2 disposed on the outer periphery of the stator core 101, and a tubular coolant flow path 3 provided inside the housing 2 and through which a coolant for cooling the stator core 101 flows.

[0019] The housing 2 is formed from a metal material such as aluminum or copper that has good thermal conductivity, and has a shape that surrounds the entire periphery of the stator core 101. The housing 2 is thermally connected to the outer peripheral surface 101c of the stator core 101. In this embodiment, the housing 2 is in direct contact with the outer peripheral surface 101c of the stator core 101. However, the housing 2 may be connected to the outer peripheral surface 101c of the stator core 101 via a heat-conductive material, such as a heat-conductive medium containing metal fine particles.

[0020] 2, a coolant flow path 3 through which the coolant flows is formed inside the housing 2. The coolant flow path 3 has a plurality of main flow path pipe sections 31, at least one inlet collecting pipe section 32, and at least one outlet collecting pipe section 33.

[0021] The main flow path pipe section 31 is disposed near the outer peripheral surface 101c of the stator core 101. In this embodiment, the multiple main flow path pipe sections 31 each extend linearly along the axial direction of the stator core 101. However, the multiple main flow path pipe sections 31 may each be provided to extend along the circumferential direction of the stator core 101. Inside the housing 2, the multiple main flow path pipe sections 31 are arranged in parallel at regular intervals in the direction D3 along the outer periphery of the stator core 101 so as to surround the stator core 101. The main flow path pipe sections 31 in this embodiment are each configured to pass a coolant from above to below in FIGS. 1 and 2 .

[0022] The inlet collecting pipe section 32 is provided in an annular shape along the outer periphery of the stator core 101. The inlet collecting pipe section 32 connects the upstream ends 31a of all the main flow path pipe sections 31 together so that they are in communication with the interiors of the main flow path pipe sections 31. As shown in FIG. 2 , the inlet collecting pipe section 32 is connected to at least one inlet pipe 321 that allows the coolant to flow into the coolant flow path 3.

[0023] Like the inlet-side collecting pipe 32, the outlet-side collecting pipe 33 is provided in an annular shape along the outer periphery of the stator core 101. The outlet-side collecting pipe 33 connects the downstream ends 31b of all the main flow path pipes 31 together so that they are each in communication with the interior of the main flow path pipes 31. As shown in FIG. 2 , the outlet-side collecting pipe 33 is connected to at least one outlet pipe 331 that discharges the coolant into the coolant flow path 3.

[0024] A vortex generating section 4 is provided inside each of all main flow path pipe sections 31, for generating a vortex in the coolant flowing through the main flow path pipe section 31. As shown in FIGS. 1 and 2, the vortex generating section 4 is located near the upstream end section 31a of the main flow path pipe section 31. The provision of this vortex generating section 4 makes it possible to easily generate a vortex in the main flow path pipe section 31, thereby improving the heat transfer performance of the coolant flow path 3. This significantly reduces the temperature gradient inside the main flow path pipe section 31, and further improves the cooling efficiency of the stator core 101, which is a heat-generating section.

[0025] 3 and 4, the vortex generating section 4 of this embodiment has a plurality of deflection plates 41 arranged along the circumferential direction of the main flow path pipe section 31 (direction D4 in FIGS. 3 and 4). The plurality of deflection plates 41 of this embodiment extend radially from the center of the main flow path pipe section 31 in the radial direction toward the inner wall surface 31c of the main flow path pipe section 31. However, the plurality of deflection plates 41 may be provided so as to extend from the inner wall surface 31c of the main flow path pipe section 31 toward the center of the main flow path pipe section 31 in the radial direction. Although the vortex generating section 4 of this embodiment has five deflection plates 41, the number of deflection plates 41 is not limited to five.

[0026] The downstream ends 41a of the deflector plates 41, which are aligned with the flow direction of the coolant, are curved in the same circumferential direction of the main flow path pipe 31. As a result, the deflector plates 41 deflect the flow of the coolant inside the main flow path pipe 31 in the same circumferential direction of the main flow path pipe 31, as shown by the arrows in the main flow path pipe 31 in FIG. 3 . Therefore, the coolant that flows from the inlet-side collecting pipe 32 into the main flow path pipe 31 collides with the multiple deflector plates 41 of the vortex generating section 4, causing it to flow in a vortex state. Because the vortex generating section 4 is disposed near the upstream end 31a of the main flow path pipe 31, the coolant that flows into the main flow path pipe 31 can maintain a vortex state throughout the entire length of the main flow path pipe 31, which extends linearly, toward the outlet-side collecting pipe 33.

[0027] As shown in Fig. 3, the multiple deflection plates 41 of the vortex generating unit 4 of this embodiment are integrally provided on the inner wall surface 31c of the main flow path pipe section 31. That is, the outer end portions 41b of the deflection plates 41 shown in Fig. 4 are each connected to the inner wall surface 31c. The coolant flowing along the inner wall surface 31c of the main flow path pipe section 31 can be deflected by colliding with the deflection plates 41, so that the entire coolant flowing through the main flow path pipe section 31 can be efficiently turned into a vortex flow. Therefore, the vortex generating unit 4 of this embodiment can more efficiently generate a vortex flow in the main flow path pipe section 31.

[0028] Such a water jacket 1 can be manufactured by additive manufacturing using the same metal material (powdered metal, metal wire, etc.) to form the housing 2 and the coolant flow path 3 having the vortex generating portion 4 inside the main flow path pipe portion 31. According to this manufacturing method, the housing 2 and the coolant flow path 3 having the vortex generating portion 4 inside the main flow path pipe portion 31 can be easily molded integrally using a 3D printer. As the metal material, an aluminum-based, copper-based, or other metal material with good thermal conductivity can be used.

[0029] In additive manufacturing using a 3D printer, for example, when powdered metal is used as the metallic material, the water jacket 1 is three-dimensionally additively manufactured along the direction D1, which is the longitudinal direction of the main flow path pipe section 31, by repeating the process of melting and solidifying the portion to be manufactured by irradiating the powdered metal spread on a base plate with a laser or electron beam as a heat source, and then moving the base plate and spreading new powdered metal. This additive manufacturing method makes it possible to easily manufacture the water jacket 1 using a 3D printer, which can further improve the cooling efficiency of the stator core 101. The vortex generated by the vortex generator 4 in the main flow path pipe section 31 also improves the removal of metal material remaining in the coolant flow path 3 after manufacturing.

[0030] In summary, the water jacket 1 according to this embodiment has the following advantages. Specifically, the water jacket 1 according to this embodiment has a coolant flow path 3 inside the housing 2, which is disposed around the outer periphery of the stator core 101, a heat-generating part. The coolant flow path 3 is disposed near the outer periphery of the stator core 101 and includes a plurality of main flow path pipe sections 31 that extend linearly and are arranged along the outer periphery of the stator core 101; an inlet-side collecting pipe section 32 that connects the upstream ends 31a of the main flow path pipe sections 31 together and allows the coolant to flow in; and an outlet-side collecting pipe section 33 that connects the downstream ends 31b of the main flow path pipe sections 31 together and allows the coolant to flow out. Each main flow path pipe section 31 has a vortex generating section 4 that generates a vortex near its upstream end 31a. This allows the vortex generating section 4 to generate a vortex in the linearly extending main flow path pipe section 31 of the coolant flow path 3, thereby improving the heat transferability of the coolant flow path 3 and further improving the cooling efficiency of the stator core 101.

[0031] The vortex generating section 4 of this embodiment has a plurality of deflection plates 41 that deflect the flow of the coolant inside the main flow path pipe section 31 in the same circumferential direction of the main flow path pipe section 31. With this, a vortex can be easily generated inside the main flow path pipe section 31 by the plurality of deflection plates 41 inside the main flow path pipe section 31.

[0032] The plurality of deflection plates 41 in this embodiment are provided integrally with the inner wall surface 31c of the main flow path pipe section 31. With this, the plurality of deflection plates 41 extending from the inner wall surface 31c of the main flow path pipe section 31 can generate vortex flows in the main flow path pipe section 31 more efficiently.

[0033] The manufacturing method for the water jacket 1 of this embodiment involves integral molding using a metal material through additive manufacturing. This allows the water jacket 1, which can further improve the cooling efficiency of the stator core 101, to be easily manufactured using a 3D printer. The vortex generated by the vortex generating section 4 in the main flow path pipe section 31 also improves the removability of metal material remaining in the coolant flow path 3 after manufacturing.

[0034] The water jacket 1 shown in the above embodiment is provided in the electric motor 100 whose heat-generating part is the stator core 101, but the heat-generating part is not limited to the electric motor 100. The water jacket 1 can be provided in various heat-generating parts that require cooling by a coolant. [Explanation of symbols]

[0035] 1 water jacket 2. Housing 3 Coolant flow path 31 Main flow pipe section 31a Upstream end 31b Downstream end 31c Inner wall 32 Inflow side collecting pipe section 33 Outlet side collecting pipe section 4 Vortex generator 41 Deflection plate 101 Stator core (heat generating part)

Claims

1. A water jacket having a coolant flow path inside a housing arranged around the outer periphery of a heat generating part, The coolant flow path is a plurality of main flow path pipe sections arranged in the vicinity of the outer periphery of the heat generating section, extending linearly and arranged along the outer periphery of the heat generating section; an inlet collecting pipe section that connects upstream ends of the main flow path pipe sections together and allows the coolant to flow into the main flow path pipe sections; an outlet-side collecting pipe section that connects downstream end sections of the main flow path pipe sections together and allows the coolant to flow out of the main flow path pipe sections; and All of the main flow path pipe sections are downstream of the inlet-side collecting pipe section and each have a vortex generating section that generates a vortex flow near the upstream end inside the main flow path pipe section.

2. The cooling liquid flow path has at least one inlet pipe that allows the cooling liquid to flow into the inlet-side collecting pipe section, the inlet-side collecting pipe portion is provided in an annular shape along an outer periphery of the heat generating portion, 2. The water jacket according to claim 1, wherein the coolant flows through the inlet pipe, is distributed around the entire circumference of the inlet collecting pipe section, is then distributed to the main flow path pipe section, and flows through the vortex generating section near the upstream end inside the main flow path pipe section.

3. 3. The water jacket according to claim 1, wherein the vortex generating portion has a plurality of deflection plates that deflect the flow of the coolant inside the main flow path pipe portion in the same circumferential direction of the main flow path pipe portion.

4. The water jacket according to claim 3 , wherein the plurality of deflection plates are provided integrally with an inner wall surface of the main flow path pipe portion.

5. A method for manufacturing a water jacket, comprising integrally molding the water jacket according to claim 1 or 2 by additive manufacturing using a metal material.

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