Oil-cooled motor circumferential non-uniform oil channel stator structure

Abstract

The application discloses an oil-cooled motor circumferential non-uniform oil channel stator structure, aiming at solving the problem that the stator in the motor is unevenly cooled by coolant, so that the local temperature far from the inlet oil channel in the stator is higher, and the motor performance is affected, and the technical problem is solved through the following technical scheme, which comprises: an iron core, an oil guide groove is arranged on the circumferential direction of the outer side wall of the iron core, an oil guide hole is arranged in the side wall of the iron core in the axial direction, and the oil guide hole is in communication with the oil guide groove; the oil guide holes are non-uniformly distributed on the circumferential side wall of the iron core. The oil guide holes are non-uniformly arranged on the circumferential direction of the side wall of the iron core, so that the loss of cooling oil is reduced when the cooling oil flows away from the first oil inlet end, the cooling oil can reach the side far from the first oil inlet, the stator cooling can be more uniform, the all-around cooling effect of the stator is achieved, and the use performance of the stator is improved.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and more specifically, to a stator structure with circumferentially non-uniform oil channels for an oil-cooled motor. Background Technology

[0002] The main heat source of the motor stator is the coil winding. When the heat is transferred outward, it mainly passes through three directions: the outside of the iron core, the inner circle of the iron core, and the ends of the winding. Most existing solutions only cool the outside of the motor iron core. However, this will cause severe overheating at the ends of the coil winding, and will also cause heat to be transferred from the air gap between the stator and rotor to the rotor, raising the rotor temperature and reducing the motor performance. This solution cannot provide all-round cooling for the motor stator.

[0003] Chinese Patent Publication No. CN206149042U, published on May 3, 2017, entitled "A Stator Cooling Structure and a Motor," discloses a stator cooling structure and a motor, specifically revealing the following technical features: a stator core, a main cooling water pipe, an end connecting device, and inlet and outlet water pipes. The stator core is formed by stacking stator laminations, with pressure rings at both axial ends. Cooling water pipe mounting holes are provided on the stator laminations and pressure rings. The main cooling water pipe is installed in the cooling water pipe mounting holes of the stator core, extending axially from both ends of the stator core. One or more main cooling water pipes form a cooling circuit at the ends of the core through the end connecting device, and inlet and outlet water pipes are provided at both ends of each cooling circuit. In the above-mentioned utility model, inlet and outlet water ports are set at both ends of the cooling circuit. However, the temperature of the cooling water is lower when it enters from the inlet end, and the cooling effect is better at this time. However, as the cooling water cools the stator through the inlet pipe, the temperature of the cooling water is higher when it is closer to the outlet, which makes the heat dissipation of the stator uneven. This results in the stator temperature being higher near the outlet, which affects the performance and service life of the motor. Summary of the Invention

[0004] This invention overcomes the shortcomings of existing technologies where the stator in an electric motor is cooled unevenly by the coolant, resulting in higher local temperatures in the stator far from the oil inlet, which affects motor performance. It provides a stator structure with circumferentially non-uniform oil channels for an oil-cooled motor, which can cool the entire structure, making the overall temperature more stable and preventing the stator far from the liquid inlet from overheating.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: a stator structure for an oil-cooled motor with circumferentially non-uniform oil channels, comprising: an iron core, wherein an oil guide groove is provided in the circumferential direction on the outer side wall of the iron core, and an oil guide hole is non-uniformly provided in the axial direction on the inner side wall of the iron core, wherein the oil guide hole is connected to the oil guide groove.

[0006] This invention addresses the issue of non-uniformly distributed oil guide holes along the circumference of the iron core's sidewall. When cooling oil enters the oil guide groove from the first oil inlet, its temperature is initially low. As the low-temperature oil passes through the guide groove and reaches the end furthest from the first oil inlet, its temperature rises. This further reduces the amount of oil flowing through the guide holes, leading to a rise in stator temperature at the end furthest from the first oil inlet. Over time, this can negatively impact stator performance. Therefore, by non-uniformly distributing oil guide holes along the circumference of the iron core's sidewall, the loss of cooling oil as it flows towards the end furthest from the first oil inlet is reduced. This ensures the cooling oil reaches the side furthest from the first oil inlet, resulting in more uniform stator cooling and a comprehensive cooling effect, thereby improving stator performance.

[0007] Preferably, the motor housing is provided with a first oil inlet hole; the oil guide holes are symmetrically distributed in the side wall of the iron core with the perpendicular line between the first oil inlet hole and the iron core axis as the axis of symmetry.

[0008] Since the cooling oil flows along both ends of the oil guide groove after entering from the first oil inlet, the cooling oil can flow along both sides by symmetrically setting the oil guide holes, so that the stator can be cooled more evenly.

[0009] Preferably, the outer side wall of the iron core is provided with multiple welding grooves in the circumferential direction.

[0010] The welding groove is designed to fix the stator to the motor housing, making the stator more stable when installed inside the housing.

[0011] Preferably, the outer wall of the iron core is symmetrically arranged with a first region, a second region, a third region, and a fourth region in sequence, with the perpendicular line between the first oil inlet hole and the iron core axis as the axis of symmetry; the included angle corresponding to the length of the arc of the first region is 39 to 41 degrees, the included angle corresponding to the length of the arc of the second region is 33 to 34 degrees, the included angle corresponding to the length of the arc of the third region is 31 to 32 degrees, and the included angle corresponding to the length of the arc of the fourth region is 75 to 78 degrees.

[0012] Analysis has shown that the above settings can improve the overall cooling effect of the stator.

[0013] Preferably, the sidewall of the iron core is provided with an inner annular groove inside the oil guide groove, and the inner annular groove is separated from the oil guide groove by the oil guide groove wall. The oil guide groove wall is provided with a second oil inlet hole that connects the inner annular groove and the oil guide groove. The oil guide groove wall is provided with a plurality of connecting holes along the circumferential direction, and the connecting holes connect the oil guide groove and the inner annular groove.

[0014] By setting a second oil inlet, a portion of the cooling oil can flow into the inner ring groove through the second oil inlet, which provides a better cooling effect on the inside of the stator. At the same time, the cooling oil entering the inner ring groove can flow into the oil guide groove through the connecting hole, which improves the cooling effect of the stator and makes the stator cool more evenly.

[0015] Preferably, an oil guide ring is provided in the inner annular groove. The oil guide ring is made of a heat-sensitive material. The outer side wall of the oil guide ring is concave to form an oil inlet groove. The second oil inlet hole is located at the middle position in the width direction of the oil guide groove wall. A second oil outlet hole is provided at the end of the oil guide groove wall away from the second oil inlet hole. The connecting holes are distributed on both sides of the width direction of the oil guide groove wall.

[0016] By incorporating an oil guide ring made of heat-sensitive material, the second oil outlet is located far from the first and second oil inlets, causing the temperature at the second oil outlet to rise first during stator operation. This temperature increase leads to an increase in the diameter of the oil guide ring. When the temperature reaches a certain level, the oil groove of the oil guide ring comes into contact with the oil groove wall, forming a sealed cavity. Cooling oil then flows into the cavity through the second oil inlet. Since the connecting holes are located on both sides of the width of the oil groove wall, the cooling oil does not flow out through the connecting holes. Instead, the cooling oil flows along the cavity until it reaches the second oil outlet, directly cooling the second oil outlet. Furthermore, as the cooling oil flows through the cavity, the oil in the oil groove absorbs some heat, resulting in lower temperatures for the cooling oil flowing out of the cavity, further improving the cooling effect on the stator at the second oil outlet. Therefore, this design allows for more uniform stator cooling, improving the overall cooling effect of the stator.

[0017] Preferably, an oil guide ring is provided in the inner annular groove, and an installation groove is provided on the inner sidewall of the inner annular groove along the circumferential direction. A connecting plate is provided on the inner sidewall of the oil guide ring, and the connecting plate is disposed in the installation groove. An abutment spring is provided in the installation groove, and the two ends of the abutment spring abut against the ends of the connecting plate and the installation groove, respectively. An oil pusher block is provided on the bottom groove surface of the oil guide groove.

[0018] To improve the flow of cooling oil within the inner annular groove, a ground connection plate is placed within the mounting groove, with a retaining spring positioned between the connection plate and the mounting groove. Since the motor vibrates during operation, especially as the motor's size increases, the connection plate's placement within the mounting groove allows the circumferential vibrations of the motor to be transmitted through the spring, causing the oil guide ring to rotate in the left circumferential direction. The oil pusher on the oil guide ring then propels the cooling oil within the inner annular groove, increasing its flow velocity and further enhancing its cooling effect on the stator. Furthermore, this design absorbs motor vibrations to a certain extent, improving the stability of the motor's movement.

[0019] Preferably, the oil pushing blocks are evenly distributed along the circumference of the oil channel, and the oil pushing blocks include vertical sections and inclined sections.

[0020] By setting vertical and inclined sections on the oil pusher block, the oil guide ring will move in two directions when it rotates due to vibration. When it rotates towards the inclined section, the inclined section will exert a smaller pushing force on the cooling oil; when it rotates towards the vertical section, the vertical section will exert a larger pushing force on the cooling oil, allowing the cooling oil to move a greater distance. This arrangement allows the cooling oil to move in one direction when pushed by the oil guide ring, increasing the flow rate of the cooling oil and improving the cooling effect of the cooling oil on the stator.

[0021] Preferably, two abutment springs are provided, which abut against both sides of the connecting plate respectively.

[0022] The above configuration allows the oil guide ring to move in both directions when subjected to vibration, thus improving the effect of the oil guide ring in pushing the cooling oil.

[0023] Preferably, the oil pusher is symmetrically arranged with the perpendicular line between the first oil inlet hole and the iron core axis as the axis of symmetry, and the inclined section faces the second oil inlet hole.

[0024] The above-mentioned setup, through the pushing action of the oil guide ring, can accelerate the flow of cooling oil from the second oil inlet to the second oil outlet, making the stator cooling more uniform.

[0025] Compared with the prior art, the beneficial effect of the present invention is that it enables the stator to cool more uniformly, improves the overall cooling effect of the stator, thereby improving the performance of the stator and increasing its service life. Attached Figure Description

[0026] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is the front view of the present invention; Figure 3This is a cross-sectional view of the second embodiment of the present invention; Figure 4 This is a side view of the second embodiment of the present invention; Figure 5 This is a cross-sectional view along the core axis of the second embodiment of the present invention; Figure 6 This is a structural diagram of the oil guide ring according to the second embodiment of the present invention; Figure 7 This is a cross-sectional view of the structure of the fourth embodiment of this invention; In the diagram: 1. Iron core, 11. First region, 12. Second region, 13. Third region, 14. Fourth region, 2. Oil guide groove, 3. Oil guide hole, 4. Weld groove, 5. Inner ring groove, 51. Mounting groove, 511. Abutment spring, 6. Oil guide groove wall, 61. Second oil inlet hole, 62. Connecting hole, 63. Second oil outlet hole, 7. Oil guide ring, 71. Oil guide groove, 72. Connecting plate, 73. Oil pusher block, 731. Vertical section, 732. Inclined section. Detailed Implementation

[0027] The technical solution of the present invention will be further described in detail below through specific embodiments and in conjunction with the accompanying drawings: Example 1: Refer to Figures 1 to 2 As shown, a stator structure with circumferentially non-uniform oil channels for an oil-cooled motor includes: an iron core 1, an oil guide groove 2 provided in the circumferential direction on the outer side wall of the iron core 1, and an oil guide hole 3 provided in the axial direction inside the side wall of the iron core 1, the oil guide hole 3 being connected to the oil guide groove 2; the oil guide holes 3 are non-uniformly distributed on the circumferential side wall of the iron core 1.

[0028] The motor housing (not shown in the figure) is provided with a first oil inlet hole (not shown in the figure); the oil guide holes 3 are symmetrically distributed in the side wall of the iron core 1 with the perpendicular line between the first oil inlet hole (not shown in the figure) and the axis of the iron core 1 as the axis of symmetry.

[0029] Multiple welding grooves 4 are provided on the circumferential direction of the outer side wall of the iron core 1. The welding grooves are used to fix the stator to the motor housing. The oil guide groove 2 is not welded to the motor housing during welding.

[0030] The outer wall of the iron core 1 is symmetrically arranged with a first region 11, a second region 12, a third region 13, and a fourth region 14, with the perpendicular line between the first oil inlet hole and the axis of the iron core 1 as the axis of symmetry. The included angle corresponding to the length of the arc of the first region 11 is 39 to 41 degrees, the included angle corresponding to the length of the arc of the second region 12 is 33 to 34 degrees, the included angle corresponding to the length of the arc of the third region 13 is 31 to 32 degrees, and the included angle corresponding to the length of the arc of the fourth region 14 is 75 to 78 degrees. In this embodiment, the included angle corresponding to the length of the arc of the first region 11 is set to 40 degrees, the included angle corresponding to the length of the arc of the second region 12 is set to 33.34 degrees, the included angle corresponding to the length of the arc of the third region 13 is set to 31.67 degrees, and the included angle corresponding to the length of the arc of the fourth region 14 is set to 74.93 degrees.

[0031] This invention addresses the issue of non-uniformly arranged oil guide holes 3 on the circumferential direction of the iron core's sidewall. When cooling oil enters the oil guide groove from the first oil inlet, its temperature is low. After passing through the oil guide groove 2 and reaching the end furthest from the first oil inlet, the temperature of the cooling oil rises. This, combined with the reduced oil volume due to the passage through the oil guide holes 3, leads to a rise in stator temperature at the end furthest from the first oil inlet. Over time, this can negatively impact stator performance. Therefore, by non-uniformly arranging the oil guide holes 3 on the circumferential direction of the iron core's sidewall, the loss of cooling oil through the guide holes 3 when flowing towards the end furthest from the first oil inlet is reduced. This ensures that the cooling oil reaches the side furthest from the first oil inlet, resulting in more uniform stator cooling and a comprehensive cooling effect, thereby improving stator performance.

[0032] In this embodiment, the cooling oil flows into the oil guide groove 2 from the first oil inlet hole and flows circumferentially along the oil guide groove 2. Then, the cooling oil flows from the oil guide groove 2 through the oil guide hole 3 to both ends of the oil guide groove 2 to achieve the cooling of the stator.

[0033] Example 2: Refer to Figures 3 to 6 As shown, this embodiment is structurally similar to the previous embodiment, except that an inner annular groove 5 is provided inside the oil guide groove 2 on the side wall of the iron core 1. The inner annular groove 5 and the oil guide groove 2 are separated by an oil guide groove wall 6. The oil guide groove wall 6 is provided with a second oil inlet hole 61 that connects the inner annular groove 5 and the oil guide groove 2. Since a first oil inlet hole is provided on the motor housing, two first oil inlets are provided on the motor housing. One of them guides the cooling oil into the oil guide groove 2. At the same time, the other first oil inlet hole is connected to the second oil inlet hole 61, so that the cooling oil can flow into the inner annular groove 5 through the second oil inlet hole 61. Multiple connecting holes 62 are provided on the oil guide groove wall 6 along the circumferential direction. The connecting holes 62 connect the oil guide groove 2 and the inner annular groove 5.

[0034] An oil guide ring 7 is provided inside the inner annular groove 5. The oil guide ring 7 is made of a heat-sensitive material, which is a prior art material. It is highly sensitive to temperature and can expand as the temperature increases. The outer wall of the oil guide ring 7 is concave to form an oil inlet groove 71. The second oil inlet hole 61 is located in the middle of the width direction of the oil guide groove wall 6. The second oil outlet hole 63 is provided at the end of the oil guide groove wall 6 away from the second oil inlet hole 61. The connecting holes 62 are distributed on both sides of the width direction of the oil guide groove wall 6.

[0035] It should be noted that in order to realize the processing of the inner ring groove 5 in this embodiment, the two iron cores need to be processed separately first, and the two processed iron cores are spliced ​​together by threads or other means. Therefore, a separating surface is provided on the oil guide groove wall 6 to separate the two iron cores. The above-mentioned separating surface is not shown in this figure.

[0036] The working principle of this embodiment is as follows: 1. When the cooling oil temperature is not high, the oil guide ring 7 does not expand due to heat. At this time, a portion of the cooling oil can flow into the inner ring groove 5 through the second oil inlet 61, which provides a better cooling effect on the stator's interior. Simultaneously, the cooling oil entering the inner ring groove 5 can flow into the oil guide groove 2 through the connecting hole 62, improving the stator's cooling effect and making the stator cool more evenly. 2. As the stator operates, and because the second oil outlet 63 is far from the first and second oil inlets 61, the temperature at the second oil outlet 63 will rise first during stator operation. This temperature increase will cause the diameter of the oil guide ring 7 to increase. When the temperature reaches a certain level, the oil guide groove 71 of the oil guide ring 7 will abut against the oil guide groove wall 6, forming a sealed cavity. At this time, the cooling oil flows into the cavity through the second oil inlet 61. Since the connecting hole 62 is located on both sides of the width direction of the oil guide groove wall 6, the cooling oil at this time will not... The cooling oil flows out through the connecting hole 62, so it flows along the cavity to the second oil outlet 63, thereby directly cooling the second oil outlet 63. Furthermore, as the cooling oil flows through the cavity, the cooling oil in the guide groove absorbs some of the heat, resulting in a lower temperature for the cooling oil flowing out of the cavity, further improving the cooling effect on the stator at the second oil outlet 63. Therefore, the above configuration allows for more uniform stator cooling and improves the overall cooling effect of the stator.

[0037] Example 3, referring to Figures 3 to 6As shown, this embodiment is structurally similar to Embodiment 2, except that an oil guide ring 7 is provided in the inner annular groove 5, and an installation groove 51 is provided along the circumferential direction on the inner sidewall of the inner annular groove 5. A connecting plate 72 is provided on the inner sidewall of the oil guide ring 7, and the connecting plate 72 is located in the installation groove 51. An abutment spring 511 is provided in the installation groove 51, and the two ends of the abutment spring 511 abut against the ends of the connecting plate 72 and the installation groove 51, respectively. Two abutment springs 511 are provided, abutting against the two sides of the connecting plate 72, respectively. An oil pusher block 73 is provided on the bottom groove surface of the oil channel 71. The oil pusher blocks 73 are evenly distributed along the circumferential direction of the oil channel 71, and the oil pusher block 73 includes a vertical section 731 and an inclined section 732.

[0038] The working principle of this embodiment is as follows: When the oil guide ring 7 rotates due to vibration, it will move in two directions. When it rotates towards the inclined section 732, the inclined section 732 will exert a smaller pushing force on the cooling oil. When it rotates towards the vertical section, the vertical section 731 will exert a larger pushing force on the cooling oil, allowing the cooling oil to move a greater distance. Through the above arrangement, the cooling oil can be pushed in one direction by the oil guide ring, which increases the flow speed of the cooling oil and improves the cooling effect of the cooling oil on the stator.

[0039] Example 4, as Figure 7 As shown, this embodiment is similar in structure to embodiment 3, except that the oil pusher 73 is symmetrically arranged with the perpendicular line between the first oil inlet hole and the axis of the iron core 1 as the axis of symmetry, and the inclined section 732 faces the second oil inlet hole 61.

[0040] Since the cooling oil flows to both ends after entering the inner ring groove 5 through the second oil inlet 61, the above arrangement makes one side of the inclined section 732 face the second oil inlet 61. This means that the cooling oil can only be pushed to the second oil outlet 63 by the pushing action of the oil guide ring 7, which can accelerate the flow of cooling oil from the second oil inlet 61 to the second oil outlet 63, making the stator cooling more uniform.

[0041] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the present invention in any way. Other variations and modifications may be made without departing from the technical solutions described in the claims.

Claims

1. A stator structure with circumferentially non-uniform oil channels for an oil-cooled motor, characterized in that, include: The iron core has an oil guide groove on the circumferential direction of the outer side wall and an oil guide hole in the axial direction inside the side wall of the iron core, and the oil guide hole is connected to the oil guide groove. The sidewall of the iron core has an inner annular groove inside the oil guide groove. The inner annular groove and the oil guide groove are separated by the oil guide groove wall. The oil guide groove wall has a second oil inlet hole that connects the inner annular groove and the oil guide groove. The motor housing has two first oil inlets, one of which guides the cooling oil into the oil guide groove, and the other is connected to the second oil inlet hole. The inner annular groove has an oil guide ring. The outer side wall of the oil guide ring is concave inward to form an oil guide groove. The second oil inlet hole is located in the middle of the width direction of the oil guide groove wall. The end of the oil guide groove wall away from the second oil inlet hole has a second oil outlet hole. There are connecting holes distributed on both sides of the width direction of the oil guide groove wall. The oil guide holes are unevenly distributed on the circumferential sidewalls of the iron core, which reduces the loss of cooling oil from the oil guide holes when the cooling oil flows to the end away from the first oil inlet hole. This allows the cooling oil to reach the side away from the first oil inlet hole, resulting in more uniform stator cooling and a comprehensive cooling effect on the stator.

2. The stator structure with circumferentially non-uniform oil channels for an oil-cooled motor according to claim 1, characterized in that, The motor housing is provided with a first oil inlet hole; the oil guide holes are symmetrically distributed inside the side wall of the iron core with the perpendicular line between the first oil inlet hole and the axis of the iron core as the axis of symmetry.

3. The stator structure with circumferentially non-uniform oil channels for an oil-cooled motor according to claim 2, characterized in that, The outer wall of the iron core has multiple weld grooves arranged in the circumferential direction.

4. The stator structure with circumferentially non-uniform oil channels for an oil-cooled motor according to claim 2 or 3, characterized in that, The outer wall of the iron core is symmetrically arranged with a first region, a second region, a third region, and a fourth region in sequence, with the perpendicular line between the first oil inlet hole and the iron core axis as the axis of symmetry. The included angle corresponding to the length of the arc of the first region is 39 to 41 degrees, the included angle corresponding to the length of the arc of the second region is 33 to 34 degrees, the included angle corresponding to the length of the arc of the third region is 31 to 32 degrees, and the included angle corresponding to the length of the arc of the fourth region is 75 to 78 degrees.

5. The stator structure with circumferentially non-uniform oil channels for an oil-cooled motor according to claim 2, characterized in that, The oil guide groove wall is provided with multiple connecting holes along the circumferential direction, and the connecting holes connect the oil guide groove and the inner ring groove.

6. The stator structure with circumferentially non-uniform oil channels for an oil-cooled motor according to claim 5, characterized in that, The oil guide ring is made of a heat-sensitive material.

7. The stator structure for a non-uniform circumferential oil channel of an oil-cooled motor according to claim 5 or 6, characterized in that, An oil guide ring is provided in the inner annular groove, and an installation groove is provided on the inner sidewall of the inner annular groove along the circumferential direction. A connecting plate is provided on the inner sidewall of the oil guide ring, and the connecting plate is provided in the installation groove. An abutment spring is provided in the installation groove, and the two ends of the abutment spring abut against the ends of the connecting plate and the installation groove, respectively. An oil pusher block is provided on the bottom groove surface of the oil guide groove.

8. The stator structure with circumferentially non-uniform oil channels for an oil-cooled motor according to claim 7, characterized in that, The oil pushing blocks are evenly distributed along the circumference of the oil inlet groove, and the oil pushing blocks include vertical sections and inclined sections.

9. The stator structure with circumferentially non-uniform oil channels for an oil-cooled motor according to claim 7, characterized in that, Two abutment springs are provided, which abut against both sides of the connecting plate respectively.

10. The stator structure for a non-uniform circumferential oil channel of an oil-cooled motor according to claim 8, characterized in that, The oil pusher is symmetrically arranged with the first oil inlet hole and the perpendicular line of the iron core axis as the axis of symmetry, and the inclined section faces the second oil inlet hole.

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