Oil-cooled injection-molded stator and motor thereof

Abstract

The present application relates to an oil-cooled injection molded stator and motor thereof, which is cooled by cooling oil flowing along the axial and radial directions of the stator, comprising a winding assembly, an injection molded part unit and a core segment group, the injection molded part unit is arranged in the core segment group by injection molding and covers the end face of the core segment group, the outer contour diameter of the injection molded part unit is smaller than the outer diameter of the core segment group, the winding assembly is inserted into the injection molded part unit in the core segment group and is attached to the end face of the injection molded part unit; the cooling oil flows into the core segment group, the cooling oil flows out from both ends of the core segment group, the cooling oil flows into the injection molded part unit along the radial direction of the core segment group and then flows out along the axial direction of the winding assembly. The insulation treatment of the stator winding is realized by the injection molding process, which replaces the traditional general insulation paper material process, and at the same time completes the fixing and limiting of the winding, which can reduce the height of the winding end, simplify the traditional assembly process, improve the insulation voltage resistance of the motor, and meet the new energy electric drive demand of high voltage and high power density.

Description

Technical Field

[0001] This invention relates to the field of oil-cooled injection molded stator technology, and in particular to an oil-cooled injection molded stator and its motor. Background Technology

[0002] The existing technical solutions mainly involve using insulating paper and end oil cooling (the most common solution in the industry). Insulation is achieved by inserting insulating paper into the slots, thus isolating the windings from the core.

[0003] Cooling is achieved by using a casing water channel (water cooling) or end spraying / spraying / spraying oil (oil guide ring / oil pipe and centripetal cooling scheme); specifically: (1) Add oil guide rings or oil pipe structures to both ends of the stator core to achieve cooling; (2) The stator core adopts a centripetal cooling structure to achieve cooling.

[0004] The following problems exist: 1. The insulating paper solution has a low thermal conductivity and limited insulation withstand voltage performance. At the same time, the thickness of the insulating paper occupies the limited space in the slot, reducing the slot fill factor; thus restricting the improvement of motor power density. 2. Current oil-cooling structures are mostly end-cooled and externally guided oil, which cannot directly contact the heat source of the winding inside the slot. This results in low heat dissipation efficiency, poor continuous output capability of the motor, and excessive local temperature rise of the winding, which can easily cause accelerated insulation aging and shorten service life.

[0005] Chinese patent application CN118659556A discloses an electric motor and a vehicle having the same. The motor includes a stator body with an oil groove forming around its outer periphery. The stator body has a first oil passage axially connected to the oil groove, extending to at least one end of the stator body and adapted to guide a cooling medium to the end of the stator body. The stator body also has a second oil passage radially connected to the oil groove, connecting the oil groove to a stator slot. According to the invention, the motor has a first oil passage axially connected to the oil groove on the stator body, which guides the cooling medium to the end of the stator body. The second oil passage radially connected to the oil groove connects the oil groove to the stator slot and guides the cooling medium into the stator slot. This patent does not integrate the insulation and cooling functions of the windings, thus improving insulation withstand voltage and heat dissipation efficiency, reducing the number of parts, and simplifying assembly complexity.

[0006] Therefore, how to integrate the functions of motor insulation, cooling and heat dissipation, and structural fixation without the need for additional independent oil rings and sealing parts, thereby reducing the number of motor parts, simplifying assembly complexity, and improving the insulation withstand voltage and heat dissipation efficiency of the stator, is an urgent problem to be solved. Summary of the Invention

[0007] The purpose of this invention is to overcome the defects of the prior art and provide an oil-cooled injection-molded stator and its motor.

[0008] The objective of this invention can be achieved through the following technical solutions: According to one aspect of the present invention, an oil-cooled injection-molded stator is provided, which is cooled by cooling oil flowing through the stator axially and radially, including a winding assembly, an injection-molded unit, and a core segment assembly. The injection-molded unit is disposed in the core segment assembly by injection molding and covers the end face of the core segment assembly. The outer contour diameter of the injection-molded unit is smaller than the outer diameter of the core segment assembly. The winding assembly is inserted into the injection-molded unit located in the core segment assembly and fits against the end face of the injection-molded unit. The cooling oil flows into the core segment assembly, flows out from both ends of the core segment assembly, flows radially into the injection molding unit of the core segment assembly, and then flows out axially along the winding assembly.

[0009] As a preferred technical solution, the core segment group includes a first stator core segment, a second stator core segment, and a third stator core segment. The injection molding unit includes a first injection molding part and a second injection molding part. The first stator core segment and the second stator core segment are symmetrically arranged on both sides of the third stator core segment, with the first stator core segment located on the outer side. The first injection molding part is injection molded onto the first stator core segment. The second stator core segment and the third stator core segment are integrally injection molded together by the second injection molding part. The first injection molding part and the second injection molding part are in close contact with each other. The winding assembly is located in the first injection molding part and the second injection molding part and forms a first axial oil passage and a second axial oil passage, respectively.

[0010] As a preferred technical solution, the diameter of the third stator core segment is smaller than the diameter of the first stator core segment and the second stator core segment, and the outer contour diameter of the first injection molded part is smaller than the diameter of the first stator core segment.

[0011] As a preferred technical solution, the first stator core segment includes a first oil hole and a first stator slot, the second stator core segment includes a radial oil passage and a second stator slot, and the third stator core segment includes a third stator slot. The first stator slot, the second stator slot, and the third stator slot are aligned and connected to each other. The first oil hole is aligned and connected to the radial oil passage, and the radial oil passage is aligned and connected to the second stator slot. The cooling oil flows out sequentially through the third stator core section, radial oil passage, first oil hole and oblique oil hole; The cooling oil flows out sequentially through the third stator core section, the radial oil passage, the second axial oil passage, and the first axial oil passage.

[0012] As a preferred technical solution, the first injection molded part includes a first end face, an inclined oil hole, a second end face, and a first receiving channel. The first end face and the second end face are respectively located at both ends of the first receiving channel. The first end face and the second end face are respectively attached to both ends of the first stator core section. The inclined oil hole is disposed on the second end face and communicates with the first oil hole. The first receiving channel is located in the first stator slot. The winding assembly is located in the first receiving channel and forms a first axial oil passage.

[0013] As a preferred technical solution, the second injection molded part includes a third end face, a boss, a distal end face, and a second receiving channel. The third end face is disposed on both sides of the second receiving channel and is in contact with the first stator core segment. The distal end face is located at the radially distal end of the second receiving channel. The boss is disposed on the distal end face and engages with the second stator core segment and is in contact with the third stator core segment. The second receiving channel is located in the second stator core segment and the third stator core segment and communicates with the second stator slot. The winding assembly is located in the second receiving channel and forms a second axial oil passage.

[0014] As a preferred technical solution, the core segment group includes a first stator core segment and a second stator core segment, and the injection molding unit includes a first injection molding part and a third injection molding part. The first stator core segment and the second stator core segment are arranged adjacent to each other. The first injection molding part is injection molded on the first stator core segment, and the third injection molding part is injection molded on the second stator core segment. The third injection molding part is respectively attached to the second stator core segment and the first injection molding part. The winding assembly is located in the first injection molding part and the third injection molding part and forms a first axial oil passage and a second axial oil passage respectively.

[0015] As a preferred technical solution, the third injection molded part includes a bonding surface, an oil hole, an annular wall, and a sealing groove. The bonding surface and the sealing groove are respectively disposed on both sides of the annular wall. The bonding surface is located on the radial inner side of the annular wall, and the sealing groove is located on the radial outer side of the annular wall. The oil hole is disposed on the annular wall, and the bonding surface and the second stator core segment are bonded and aligned.

[0016] As a preferred technical solution, the second stator core section further includes a second oil hole arranged circumferentially, the diameter of which is larger than the diameter of the annular wall; The cooling oil passes through the annular wall and the second oil hole in sequence, and finally flows out from the first axial oil passage and the second axial oil passage. The cooling oil passes through the annular wall and flows out through the oil hole of the injection molded part.

[0017] According to another aspect of the present invention, an oil-cooled injection-molded motor is provided, employing an oil-cooled injection-molded stator as described in any of the above.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention achieves insulation treatment of the stator winding through injection molding, replacing the traditional commonly used insulating paper material process. At the same time, it completes the fixing and limiting of the winding, which can reduce the height of the winding end, simplify the traditional assembly process, and help improve the insulation withstand voltage capability of the motor, thus meeting the needs of high-voltage and high-power-density new energy electric drives.

[0019] 2. The oil-cooled injection-molded stator structure proposed in this invention integrates the functions of motor insulation, cooling and heat dissipation, and structural fixation. It eliminates the need for additional independent oil rings and sealing parts, reduces the number of motor parts, simplifies assembly complexity, and the injection-molded structure can improve the overall rigidity of the stator. At the same time, the motor slot fill factor is increased under the same volume, and the motor power density will also be improved accordingly.

[0020] 3. The present invention uses injection molding material to fully wrap the stator slots and ends to form cooling oil channels, which allows cooling oil to flow directly between the injection molding material and the windings, achieving a deep cooling effect on the windings inside the slots, solving the problems of high temperature and insulation aging in the windings inside the slots, and extending the service life of the motor.

[0021] 4. This invention, through stator cores with different characteristics and injection molding process, forms a centripetal cooling structure on the outside of the stator assembly, which can spray the winding position at different radial angles, greatly reducing the thermal resistance at the stator end. Combined with the in-slot cooling structure, it can achieve uniform cooling and heat dissipation throughout the stator core and winding, improving the motor's continuous overload capacity and working stability. Attached Figure Description

[0022] Figure 1 This is an exploded view of the first overall structure of the oil-cooled injection-molded stator of the present invention; Figure 2 A first overall structural cross-sectional view of the oil-cooled injection-molded stator of the present invention; Figure 3 This is a schematic diagram of the structure of the first injection molded part of the present invention; Figure 4 This is a schematic diagram of the structure of the second injection molded part of the present invention; Figure 5 This is a partial structural schematic diagram of the second injection molded part of the present invention; Figure 6 This is a schematic diagram of the first injection molded part and the first stator core of the present invention. Figure 7 This is an enlarged schematic diagram of the area where the first injection molded part and the first stator core of the present invention are joined; Figure 8 This is a schematic diagram showing the combination of the second injection molded part and the second and third stator core sections of the present invention; Figure 9This is an enlarged schematic diagram of the area where the second injection molded part and the second and third stator core sections of the present invention are joined. Figure 10 This is a schematic diagram of the first stator core section structure of the present invention; Figure 11 This is a schematic diagram of the second stator core section structure of the present invention; Figure 12 This is a schematic diagram of the third stator core section structure of the present invention; Figure 13 This is a schematic diagram of the winding assembly of the present invention inserted into the first injection molded part; Figure 14 This is a schematic diagram of the winding assembly of the present invention with the second injection molded part inserted. Figure 15 This is an exploded view of the second overall structure of the oil-cooled injection-molded stator of the present invention; Figure 16 A second overall structural cross-sectional view of the oil-cooled injection-molded stator of the present invention; Figure 17 This is a schematic diagram of the third injection molded part of the present invention; Figure 18 This is a schematic diagram of the combination structure of the third injection molded part and the second stator core section of the present invention; 1. Winding assembly; 2. First injection molded part; 3. First stator core section; 4. Second injection molded part; 5. Second stator core section; 6. Third stator core section; 7. Third injection molded part; 10. First axial oil passage; 11. Second axial oil passage; 21. First end face; 22. Inclined oil hole; 23. Second end face; 24. First receiving channel; 31. First oil hole; 32. First stator groove; 41. Third end face; 42. Boss; 43. Far end face; 44. Second receiving channel; 51. Radial oil passage; 52. Second stator groove; 53. Second oil hole; 61. Third stator groove; 71. Mating surface; 72. Oil hole of injection molded part; 73. Annular wall; 74. Sealing groove. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0024] Example 1 An oil-cooled injection-molded stator is cooled by cooling oil flowing through the stator axially and radially. It includes a winding assembly 1, an injection-molded unit, and a core segment assembly. The injection-molded unit is injection-molded and disposed in the core segment assembly and covers the end face of the core segment assembly. The outer diameter of the injection-molded unit is smaller than the outer diameter of the core segment assembly. The winding assembly 1 is inserted into the injection-molded unit located in the core segment assembly and fits against the end face of the injection-molded unit. The cooling oil flows into the core segment assembly, flows out from both ends of the core segment assembly, flows radially into the injection molding unit along the core segment assembly, and then flows out along the axial direction of the winding assembly 1.

[0025] In this embodiment, the stator is mainly composed of three parts: winding assembly 1, injection molded part unit, and core segment group. The core segment group is injection molded, and the injection molded part unit covers both ends of the core segment group. The winding assembly 1 is inserted into the injection molded part unit to realize the installation of the winding assembly 1 and the core segment group.

[0026] Cooling is achieved using either cooling oil or coolant. The cooling oil flows into the circumferential surface of the core segment assembly and then flows axially from the far end of the core segment assembly to both ends of the stator. Alternatively, the cooling oil can first flow into the circumferential surface of the core segment assembly and then flow radially from the far end to the near end, flowing into winding assembly 1 and making full contact. Finally, it flows axially along winding assembly 1 (stator) to both ends of the stator. By allowing the cooling oil to flow simultaneously across the circumferential edge and interior of the stator, and by using injection-molded units to insulate and seal the winding assembly 1, while simultaneously allowing the cooling oil to contact the winding assembly 1 directly, direct contact cooling of the winding assembly 1 is achieved. This improves the motor's insulation withstand voltage and heat dissipation efficiency, meeting the requirements of high-voltage, high-power-density motors.

[0027] There are two main structural arrangements for the core segment group and injection molded part unit.

[0028] The first method: like Figure 1 and Figure 2 As shown, the core segment group includes a first stator core segment 3, a second stator core segment 5, and a third stator core segment 6. The injection molding unit includes a first injection molding part 2 and a second injection molding part 4. The first stator core segment 3 and the second stator core segment 5 are symmetrically arranged on both sides of the third stator core segment 6, with the first stator core segment 3 located on the outer side. The first injection molding part 2 is injection molded onto the first stator core segment 3. The second stator core segment 5 and the third stator core segment 6 are integrally injection molded together by the second injection molding part 4. The first injection molding part 2 and the second injection molding part 4 are closely fitted to each other. The winding assembly 1 is located in the first injection molding part 2 and the second injection molding part 4 and forms a first axial oil passage 10 and a second axial oil passage 11, respectively.

[0029] In this embodiment, the core segment group consists of three types of core segments: a first stator core segment 3, a second stator core segment 5, and a third stator core segment 6. The third stator core segment 6 is located in the middle, and the first stator core segment 3 and the second stator core segment 5 are symmetrically arranged on both sides of the third stator core segment 6. That is, the second stator core segment 5 is first symmetrically arranged on both sides of the third stator core segment 6, and then the first stator core segment 3 is arranged on the outer side of the second stator core segments 5 at both ends, forming an arrangement of first stator core segment 3 - second stator core segment 5 - third stator core segment 6 - second stator core segment 5 - first stator core segment 3.

[0030] The injection-molded unit consists of a first injection-molded part 2 and a second injection-molded part 4. The first injection-molded part 2 is injection-molded onto the first stator core section 3. The third stator core section 6 and two second stator core sections 5 symmetrically arranged at both ends are integrally injection-molded together through the second injection-molded part 4. The first injection-molded part 2 and the second injection-molded part 4 at both ends are fitted together. The winding assembly 1 is inserted from the first injection-molded part 2 at one end, passes through the second injection-molded part 4, and then exits from the second injection-molded part 4 at the other end.

[0031] The diameter of the third stator core segment 6 is smaller than the diameter of the first stator core segment 3 and the second stator core segment 5, and the outer contour diameter of the first injection molded part 2 is smaller than the diameter of the first stator core segment 3.

[0032] In this embodiment, the diameter of the third stator core segment 6 is smaller than that of the other stator core segments. The third stator core segment 6 and the adjacent second stator core segment 5 form an oil groove, facilitating the entry of cooling oil from the middle oil groove into the adjacent second stator core segment 5, and then dissipating heat along the corresponding oil path. The outer contour of the first injection molded part 2 is lower than the diameter of the first stator core segment 3, facilitating the fit between the stator and the housing shoulder. The diameters of the first stator core segment 3 and the second stator core segment 5 are the same.

[0033] like Figure 10 , Figure 11 and Figure 12 The first stator core segment 3 includes a first oil hole 31 and a first stator slot 32, the second stator core segment 5 includes a radial oil channel 51 and a second stator slot 52, and the third stator core segment 6 includes a third stator slot 61. The first stator slot 32, the second stator slot 52 and the third stator slot 61 are aligned and connected. The first oil hole 31 is aligned and connected with the radial oil channel 51. The radial oil channel 51 is aligned and connected with the second stator slot 52. The cooling oil flows out sequentially through the third stator core section 6, radial oil channel 51, first oil hole 31 and inclined oil hole 22; the cooling oil flows out sequentially through the third stator core section 6, radial oil channel 51, second axial oil channel 11 and first axial oil channel 10.

[0034] In this embodiment, a first oil hole 31 and a first stator slot 32 are arranged in a ring on the first stator core section 3; a radial oil channel 51 and a second stator slot 52 are arranged in a ring on the second stator core section 5; and a third stator slot 61 is arranged in a ring on the third stator core section 6. The first stator slot 32, the second stator slot 52, and the third stator slot 61 are of the same size and are aligned with each other. The radial oil channel 51 is arranged in the radial direction and communicates with the second stator slot 52. At the same time, the radial oil channel 51 communicates with the second injection molded part 4, so that cooling oil can flow from the radial oil channel 51 into the second injection molded part 4. The first oil hole 31 is aligned with and communicates with the radial oil channel 51. The first oil hole 31 is arranged in a ring, which is the outer ring, close to the circumferential edge; the first stator slot 32 is arranged in a ring, which is the inner ring, close to the axis of the first stator core section 3.

[0035] The cooling oil first flows into the third stator core section 6 in the middle of the stator, and then flows into the radial oil passage 51 of the second stator core section 5. At this time, the flow direction of the cooling oil begins to split. One path of cooling oil flows from the radial oil passage 51 and the first oil hole 31 from the middle of the stator to both ends (flowing along the axial direction of the outer ring). The other path of cooling oil flows from the radial oil passage 51, the second axial oil passage 11 (i.e., the second injection molded part 4), and the first axial oil passage 10 (i.e., the first injection molded part 2).

[0036] like Figure 3 , Figure 6 and Figure 7 As shown, the first injection molded part 2 includes a first end face 21, an inclined oil hole 22, a second end face 23, and a first receiving channel 24. The first end face 21 and the second end face 23 are respectively located at both ends of the first receiving channel 24. The first end face 21 and the second end face 23 are respectively attached to both ends of the first stator core section 3. The inclined oil hole 22 is disposed on the second end face 23 and communicates with the first oil hole 31. The first receiving channel 24 is located in the first stator slot 32. The winding assembly 1 is located in the first receiving channel 24 and forms a first axial oil passage 10.

[0037] In this embodiment, the first injection molded part 2 includes a first end face 21, an inclined oil hole 22, a second end face 23, and a first receiving channel 24. The first receiving channel 24 is used to receive the winding assembly 1. The first end face 21 and the second end face 23 are respectively provided at both ends of the first receiving channel 24. The first end face 21 and the second end face 23 are respectively attached to both ends of the first stator core segment 3. The first end face 21 is attached to the second injection molded part 4, and the second end face 23 is attached to the end face of the winding assembly 1. The second end face 23 is similar to the end face of the first stator core segment 3, except that an inclined oil hole 22 is provided on the second end face 23. The inclined oil hole 22 is connected to the first oil hole 31 on the first stator core segment 3. Cooling oil flows out from the first oil hole 31 and enters the inclined oil hole 22. At the same time, the diameter of the second end face 23 (the outer contour of the first injection molded part 2) is smaller than the diameter of the first stator core segment 3, which facilitates the fit between the stator and the housing shoulder. Since the first injection molded part 2 is injection molded, the dimensions of the first receiving channel 24 and the first stator slot 32 are matched. After the winding assembly 1 is inserted into the first injection molded part 2, there is a certain gap between the winding assembly 1 and the first receiving channel 24. This gap is the first axial oil passage 10, through which the cooling oil flows out.

[0038] like Figure 4 , Figure 5 , Figure 8 and Figure 9 As shown, the second injection molded part 4 includes a third end face 41, a boss 42, a distal end face 43, and a second receiving channel 44. The third end face 41 is disposed on both sides of the second receiving channel 44. The third end face 41 is in contact with the first stator core segment 3, and when in contact with other stator segments, the third end face 41 contacts the corresponding structure on the injection molded part. The distal end face 43 is located at the radially distal end of the second receiving channel 44. The boss 42 is disposed on the distal end face 43 and engages with the second stator core segment 5 and is in contact with the third stator core segment 6. The second receiving channel 44 is located in the second stator core segment 5 and the third stator core segment 6. The second receiving channel 44 communicates with the second stator slot 52. The winding assembly 1 is located in the second receiving channel 44 and forms a second axial oil passage 11, as shown. Figure 13 As shown.

[0039] In this embodiment, the second injection molded part 4 mainly consists of a third end face 41, a boss 42, a distal end face 43, and a second receiving channel 44. The second receiving channel 44 serves as the main body and is used to accommodate the winding assembly 1. Third end faces 41 are provided at both ends of the second receiving channel 44, and the third end faces 41 are fitted to the first end face 21. A distal end face 43 is provided at the radially distal end (top) of the second receiving channel 44, and two bosses 42 are provided on the distal end face 43, which respectively engage with the second stator core segment 5. Since the second injection molded part 4 is injection molded, the dimensions of the second receiving channel 44 and the second stator slot 32 are matched. After the winding assembly 1 is inserted into the second injection molded part 4, there is a certain gap between the winding assembly 1 and the second receiving channel 44. This gap is the second axial oil passage 11, through which cooling oil flows out. Figure 14 As shown; correspondingly, the second receiving channel 44 is connected to the second stator slot 52, and cooling oil flows into the second receiving channel 44 from the radial oil passage 51. The first receiving channel 24 is aligned and fits into the second receiving channel 44, realizing the connection between the first axial oil passage 10 and the second axial oil passage 11.

[0040] Cooling oil flows sequentially through the third stator core section 6, radial oil passage 51, second axial oil passage 11, and first axial oil passage 10 before exiting both ends of the stator.

[0041] Example 2 Another structural arrangement like Figure 15 and Figure 16 As shown, the core segment group includes a first stator core segment 3 and a second stator core segment 5. The injection molding unit includes a first injection molding part 2 and a third injection molding part 7. The first stator core segment 3 and the second stator core segment 5 are arranged adjacent to each other. The first injection molding part 2 is injection molded on the first stator core segment 3, and the third injection molding part 7 is injection molded on the second stator core segment 5. The third injection molding part 7 is respectively attached to the second stator core segment 5 and the first injection molding part 2. The winding assembly 1 is located in the first injection molding part 2 and the third injection molding part 7 and forms a first axial oil passage 10 and a second axial oil passage 11 respectively.

[0042] In this embodiment, the core segment assembly consists of a first stator core segment 3 and a second stator core segment 5, and the injection molding unit consists of a first injection molding part 2 and a third injection molding part 7. The first stator core segment 3 and the second stator core segment 5 are arranged adjacent to each other. The first injection molding part 2 is still injection molded on the first stator core segment 3, and the third injection molding part 7 is injection molded on the second stator core segment 5 and is attached to the first injection molding part 2. The winding assembly 1 is inserted into the first injection molding part 2 to form a first axial oil passage 10, and inserted into the third injection molding part 7 to form a second axial oil passage 11. The first axial oil passage 10 and the second axial oil passage 11 are connected.

[0043] like Figure 17and Figure 18 As shown, the third injection molded part 7 includes a mating surface 71, an injection molded part oil hole 72, an annular wall 73, and a sealing groove 74. The mating surface 71 and the sealing groove 74 are respectively disposed on both sides of the annular wall 73. The mating surface 71 is located on the radial inner side of the annular wall 73, and the sealing groove 74 is located on the radial outer side of the annular wall 73. The injection molded part oil hole 72 is disposed on the annular wall 73. The mating surface 71 and the second stator core segment group 5 are mated and aligned.

[0044] The second stator core section 5 also includes a second oil hole 53 arranged circumferentially, the diameter of which is larger than the diameter of the annular wall 73; The cooling oil passes sequentially through the annular wall 73 and the second oil hole 53, and finally flows out from the first axial oil passage 10 and the second axial oil passage 11. The cooling oil flows out through the annular wall 73 and the oil hole 72 of the injection molded part.

[0045] In this embodiment, the third injection-molded part 7 is similar to an end cap, with a mating surface 71 and a sealing groove 74 distributed at both ends of the annular wall 73. The mating surface 71 is located radially inner to the annular wall 73, and the sealing groove 74 is located radially outer to the annular wall 73. When the mating surface 71 is mated with the end face of the second stator core segment 5, and the diameter of the annular wall 73 is smaller than the diameter of the second stator core segment 5, an annular oil groove is formed between the end face of the second stator core segment 5, the annular wall 73, and the sealing groove 74. Cooling oil first flows into the oil groove and then flows through the remaining part. An end chamber is formed between the mating surface 71 and the annular wall 73, and the winding assembly 1 enters the end chamber after being inserted into the second stator core segment 5.

[0046] The third injection molded part 7 fits into the second stator groove 52 to form the second axial oil passage 11, which is connected to the radial oil passage 51, referring to the formation process of the second axial oil passage 11 in embodiment 1.

[0047] An injection molding oil hole 72 is provided on the annular wall 73 to facilitate the entry of cooling oil into the end chamber. A second oil hole 53 is also provided on the second stator core section 5, which communicates with the radial oil channel 51. The second oil hole 53 is a group of second oil holes 5 arranged along the circumference of the second stator core section 5. The diameter of the second oil hole 53 arranged around the circumference is larger than the diameter of the annular wall 73, so that the cooling oil can flow into the second oil hole 53 after entering the annular wall 73.

[0048] Flow path of cooling oil: The cooling oil first flows into the annular wall 73 of the third injection molded part 7. At this time, the cooling oil flows in two directions: one flows out through the injection molded part oil hole 72 on the annular wall 73 and enters the end chamber; the other cooling oil flows out through the annular wall 73, the second oil hole 52 and the radial oil passage 51, and finally flows out from the first axial oil passage 10 and the second axial oil passage 11.

[0049] And referring to the outer ring outflow method in Example 1, specifically, the cooling oil flows out sequentially through the ring wall 73, the second oil hole 52, and the first oil hole 31.

[0050] Example 3 An oil-cooled injection-molded motor, wherein the motor adopts the aforementioned oil-cooled injection-molded stator.

[0051] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An oil-cooled injection-molded stator, cooled by cooling oil flowing axially and radially through the stator, characterized in that, It includes a winding assembly (1), an injection molded unit and an iron core segment group. The injection molded unit is disposed in the iron core segment group by injection molding and covers the end face of the iron core segment group. The outer contour diameter of the injection molded unit is smaller than the outer diameter of the iron core segment group. The winding assembly (1) is inserted into the injection molded unit located in the iron core segment group and fits against the end face of the injection molded unit. The cooling oil flows into the core segment group, flows out from both ends of the core segment group, flows into the injection molding unit radially along the core segment group, and then flows out along the axial direction of the winding assembly (1).

2. The oil-cooled injection-molded stator according to claim 1, characterized in that, The core segment group includes a first stator core segment (3), a second stator core segment (5), and a third stator core segment (6). The injection molding unit includes a first injection molding part (2) and a second injection molding part (4). The first stator core segment (3) and the second stator core segment (5) are symmetrically arranged on both sides of the third stator core segment (6), and the first stator core segment (3) is located on the outside. The first injection molding part (2) is injection molded on the first stator core segment (3). The second stator core segment (5) and the third stator core segment (6) are integrally injection molded together by the second injection molding part (4). The first injection molding part (2) and the second injection molding part (4) are attached to each other. The winding assembly (1) is located in the first injection molding part (2) and the second injection molding part (4) and forms a first axial oil passage (10) and a second axial oil passage (11) respectively.

3. The oil-cooled injection-molded stator according to claim 2, characterized in that, The diameter of the third stator core segment (6) is smaller than the diameter of the first stator core segment (3) and the second stator core segment (5), and the outer contour diameter of the first injection molded part (2) is smaller than the diameter of the first stator core segment (3).

4. The oil-cooled injection-molded stator according to claim 2, characterized in that, The first stator core segment (3) includes a first oil hole (31) and a first stator slot (32), the second stator core segment (5) includes a radial oil passage (51) and a second stator slot (52), and the third stator core segment (6) includes a third stator slot (61). The first stator slot (32), the second stator slot (52) and the third stator slot (61) are aligned and connected. The first oil hole (31) is aligned and connected with the radial oil passage (51). The radial oil passage (51) is aligned and connected with the second stator slot (52). The cooling oil flows out sequentially through the third stator core section (6), radial oil passage (51), first oil hole (31) and oblique oil hole (22); The cooling oil flows out sequentially through the third stator core section (6), radial oil passage (51), second axial oil passage (11) and first axial oil passage (10).

5. An oil-cooled injection-molded stator according to claim 2, characterized in that, The first injection molded part (2) includes a first end face (21), an inclined oil hole (22), a second end face (23), and a first receiving channel (24). The first end face (21) and the second end face (23) are respectively located at both ends of the first receiving channel (24). The first end face (21) and the second end face (23) are respectively attached to both ends of the first stator core section (3). The inclined oil hole (22) is set on the second end face (23) and communicates with the first oil hole (31). The first receiving channel (24) is located in the first stator slot (32). The winding assembly (1) is located in the first receiving channel (24) and forms a first axial oil passage (10).

6. The oil-cooled injection-molded stator according to claim 2, characterized in that, The second injection molded part (4) includes a third end face (41), a boss (42), a distal end face (43), and a second receiving channel (44). The third end face (41) is disposed on both sides of the second receiving channel (44). The third end face (41) is in contact with the first stator core segment (3). The distal end face (43) is located at the radial distal end of the second receiving channel (44). The boss (42) is disposed on the distal end face (43) and engages with the second stator core segment (5) and is in contact with the third stator core segment (6). The second receiving channel (44) is located in the second stator core segment (5) and the third stator core segment (6). The second receiving channel (44) is connected to the second stator slot (52). The winding assembly (1) is located in the second receiving channel (44) and forms a second axial oil passage (11).

7. The oil-cooled injection-molded stator according to claim 1, characterized in that, The core segment group includes a first stator core segment (3) and a second stator core segment (5). The injection molding unit includes a first injection molding part (2) and a third injection molding part (7). The first stator core segment (3) and the second stator core segment (5) are arranged adjacent to each other. The first injection molding part (2) is injection molded on the first stator core segment (3). The third injection molding part (7) is injection molded on the second stator core segment (5). The third injection molding part (7) is attached to the second stator core segment (5) and the first injection molding part (2) respectively. The winding assembly (1) is located in the first injection molding part (2) and the third injection molding part (7) and forms a first axial oil passage (10) and a second axial oil passage (11) respectively.

8. An oil-cooled injection-molded stator according to claim 7, characterized in that, The third injection molded part (7) includes a mating surface (71), an injection molded part oil hole (72), an annular wall (73) and a sealing groove (74). The mating surface (71) and the sealing groove (74) are respectively disposed on both sides of the annular wall (73). The mating surface (71) is located on the radial inner side of the annular wall (73), and the sealing groove (74) is located on the radial outer side of the annular wall (73). The injection molded part oil hole (72) is disposed on the annular wall (73). The mating surface (71) is mated and aligned with the second stator core segment group (5).

9. An oil-cooled injection-molded stator according to claim 8, characterized in that, The second stator core section (5) also includes a second oil hole (53) arranged circumferentially, the diameter of which is larger than the diameter of the annular wall (73); The cooling oil passes through the annular wall (73) and the second oil hole (53) in sequence, and finally flows out from the first axial oil passage (10) and the second axial oil passage (11); The cooling oil flows through the annular wall (73) and out through the oil hole (72) of the injection molded part.

10. An oil-cooled injection molding motor, characterized in that, The oil-cooled injection-molded stator as described in any one of claims 1-9 is used.

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