Rotor shaft and motor assembly
By designing cavities and helical grooves on the rotor shaft, the circulation of cooling fluid is achieved, solving the problem of poor heat dissipation in the motor and improving the reliability and lifespan of the motor components.
Patent Information
- Application Number
- CN202423078636.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-12
- Publication Date
- 2026-01-23
- Estimated Expiration
- 2034-12-12
AI Technical Summary
The existing motor has poor heat dissipation during operation, which leads to the overheating and failure of the lubricating grease, and in turn, the failure of the bearing, affecting the reliability and life of the motor.
Design a rotor shaft including an axially extending cavity and a helical groove, and guide the circulation of cooling fluid through an opening in the cavity that connects to the outside to achieve lubrication and cooling of the bearing.
It effectively removes the heat generated by the motor assembly during operation, reduces the temperature, and improves the reliability and lifespan of the motor assembly.
Smart Images
Figure CN223829147U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the field of motor structures. More specifically, the present application relates to a rotor shaft which aims to provide improved cooling capacity. The present application also relates to a motor assembly comprising the above rotor shaft. BACKGROUND
[0002] Power losses such as copper losses and iron losses of a motor during operation are converted into heat. If the motor is not well cooled, such heat will accumulate inside the motor and cause the motor to overheat and fail as the operation time increases. Therefore, how to improve the cooling condition is one of the key factors in designing a high power density motor. Some motor structures have been proposed in the art to effectively discharge the heat inside the motor to the outside of the motor and cool the motor itself. Generally, the bearings at both ends of the motor shaft are grease-lubricated, which has poor heat dissipation effect and is prone to cause the grease to overheat and fail, thereby failing to effectively lubricate the bearings and causing the bearings to fail. Therefore, there is a continuous need for motor cooling solutions in the art. SUMMARY
[0003] It is an object of one aspect of the present application to provide a rotor shaft which can provide improved cooling capacity and guide a cooling fluid through a motor assembly. It is an object of another aspect of the present application to provide a motor assembly comprising the above rotor shaft.
[0004] The object of the present application is achieved by the following technical solutions:
[0005] A rotor shaft comprising:
[0006] a first housing mounting section configured to be mounted to a first end cover of a motor assembly;
[0007] a second housing mounting section configured to be mounted to a second end cover of the motor assembly;
[0008] a first cavity extending from the first housing mounting section to the second housing mounting section along an axial direction;
[0009] at least one first opening provided at the first housing mounting section and communicating the first cavity with an outside of the rotor shaft; and
[0010] at least one second opening provided at the second housing mounting section and communicating the first cavity with the outside of the rotor shaft;
[0011] wherein one or more helical grooves are arranged on an inner wall of the first cavity, the helical grooves extending from the first opening to the second opening; and
[0012] The second opening is configured to extend along the first axis on a radial cross-section of the rotor shaft, and a first predetermined angle is formed between the first axis and a radial direction.
[0013] In the above rotor shaft, optionally, the first opening is configured to extend in an axial direction.
[0014] In the above rotor shaft, optionally, the plurality of second openings are uniformly or non-uniformly distributed around the first cavity on the radial cross-section, and at least some of the plurality of second openings are in communication with the helical grooves.
[0015] In the above rotor shaft, optionally, the first predetermined angle is set to be between 30 degrees and 60 degrees.
[0016] In the above rotor shaft, optionally, the plurality of helical grooves are spaced apart from each other on an inner wall of the first cavity; wherein the helical grooves are recessed toward an outer surface of the rotor shaft with respect to the inner wall of the first cavity.
[0017] A motor assembly comprising:
[0018] a rotor configured to extend in an axial direction;
[0019] the above rotor shaft, wherein the rotor is arranged around the rotor shaft;
[0020] a stator arranged at an outer periphery of the rotor;
[0021] a housing accommodating the stator and the rotor, the stator being attached to the housing;
[0022] a first end cover attached to the housing, and a first housing mounting section of the rotor shaft being rotatably attached to the first end cover; and
[0023] a second end cover attached to the housing, and a second housing mounting section of the rotor shaft being rotatably attached to the second end cover.
[0024] In the above motor assembly, optionally, a first oil seal member and a first bearing are included, the first oil seal member and the first bearing being arranged between an outer periphery of the first housing mounting section and the first end cover, and the first oil seal member, the first housing mounting section, and the first end cover collectively enclose a second cavity, and the first bearing is located within the second cavity; wherein the first opening is in communication with the first cavity, and the first end cover includes an input port for a cooling liquid, the input port being in communication with the first cavity.
[0025] In the motor assembly described above, optionally, a second oil seal member and a second bearing are included, the second oil seal member and the second bearing are arranged between the outer periphery of the second housing mounting section and the second end cover, and the second oil seal member, the second housing mounting section and the second end cover jointly enclose a third cavity, and the second bearing is located within the second cavity; wherein the second opening is in communication with the third cavity, and the second end cover comprises an outlet for the cooling liquid, the outlet being in communication with the third cavity.
[0026] In the motor assembly described above, optionally, a third oil seal member is further included, the third oil seal member is arranged between the outer periphery of the second housing mounting section and the second end cover, and such that the second bearing is located between the second oil seal member and the third oil seal member, the second end cover further comprises an annular protrusion, and the protrusion is arranged between the second bearing and the third oil seal member.
[0027] In the motor assembly described above, optionally, the outlet comprises a first section extending in a radial direction and a second section extending in an axial direction, the first section is in communication with the second cavity, and the second section is in communication with the first section; in a radial plane, the first section and the second section respectively extend over a second predetermined angle on the inner wall of the second end cover, such that the outlet is formed as a part of an annulus, wherein the second predetermined angle is arranged to be between 30 degrees and 120 degrees. BRIEF DESCRIPTION OF DRAWINGS
[0028] The present application will be described in further detail in the following with reference to the drawings and preferred embodiments. The skilled person will appreciate that the drawings are only drawn for the purpose of explaining the preferred embodiments and should therefore not be regarded as limiting the scope of the present application. Furthermore, unless specifically indicated, the drawings are only intended to conceptually represent the composition or construction of the described objects and can include exaggerated displays. The drawings are also not necessarily drawn to scale.
[0029] Figure 1 is a perspective view of one embodiment of a rotor shaft of the present application.
[0030] Figure 2 is a perspective view of one embodiment of a rotor shaft of the present application. Figure 1 is an axial cross-sectional view of the embodiment shown.
[0031] Figure 3 is an axial cross-sectional view of the embodiment shown. Figure 1 is a radial cross-sectional view of the embodiment shown at the position indicated by the B-B line in Figure 2
[0032] Figure 4 is a perspective view of one embodiment of a motor assembly of the present application.
[0033] Figure 5 is a front view of the embodiment shown. Figure 4
[0034] Figure 6 is a perspective view of a second end cap of the electric machine assembly of the present application. DETAILED DESCRIPTION
[0035] The preferred embodiments of the present application will be described in detail below with reference to the attached drawings. Those skilled in the art will appreciate that the description is
[0036] First, it should be noted that the terms top, bottom, upward, downward, and the like used herein are defined with reference to the orientation in the various drawings. These terms are relative concepts and will therefore vary depending on the position and state in which they are placed. These or other terms of orientation should therefore not be interpreted as limiting.
[0037] Furthermore, it should be noted that any single technical feature described or implied in the embodiments herein or shown or implied in the drawings can continue to be combined with any other technical feature described or implied in the embodiments herein or shown or implied in the drawings, so as to obtain other embodiments not directly mentioned herein.
[0038] It should be noted that the same reference numerals are used in different drawings to designate the same or substantially similar components.
[0039] The axial direction A-A referred to herein is the direction of the extension axis or the axis of symmetry of the rotor shaft 11. The radial direction R-R referred to herein is the direction in which a ray emanating from a point on the extension axis or the axis of symmetry of the rotor shaft 11 extends in a plane perpendicular to the axial direction A-A.
[0040] Figures 1 to 3 Different aspects of an embodiment of a rotor shaft 11 of the present application are shown. The rotor shaft 11 can be a tubular structure extending substantially along the axial direction A-A. The rotor shaft 11 can comprise at least a first housing mounting section 110 and a second housing mounting section 120. The first and second housing mounting sections 110, 120 can be configured to be adapted for mounting to the first and second end caps 40, 50 of the electric machine assembly 1, respectively, as shown in more detail in subsequent figures. It will be readily appreciated that the rotor shaft 11 can comprise further sections, such as an extension section between the first and second housing mounting sections 110, 120, an alternative mounting section extending from the second housing mounting section 120, etc.
[0041] As Figure 2As shown, a first cavity 101 can be formed inside the rotor shaft 11. The first cavity 101 can be of a blind hole structure, and can extend from one end of the rotor shaft 11 towards the inside of the rotor shaft 11. The other end of the rotor shaft 11 can form a fourth cavity 104, and the first cavity 101 can be spaced apart from the fourth cavity 104 by a wall 103. In one embodiment, the first cavity 101 can be of a substantially cylindrical configuration, and have an inner wall. The first cavity 101 can extend from the first housing mounting section 110 to the second housing mounting section 120, and can extend along a substantially axial direction A-A.
[0042] The rotor shaft 11 can include at least one first opening 111 and at least one second opening 121. The first opening 111 can be arranged at the first housing mounting section 110, and in communication with the first cavity 101. The second opening 121 can be arranged at the second housing mounting section 120, and in communication with the first cavity 101. In one embodiment, the first opening 111 can be located at an axial end of the rotor shaft 11, and can be open towards the axial direction A-A. In one embodiment, a plurality of second openings 121 can extend from the inner wall of the first cavity 101 to the outer periphery of the rotor shaft 11. As shown, Figure 3 As shown, the second openings 121 can extend on a radial cross-section of the rotor shaft 11, and can extend along a first axis A1-A1. In one embodiment, the first axis A1-A1 can form a first predetermined angle B1 with the radial direction R-R. The first predetermined angle B1 can be between 30 degrees to 60 degrees, such as 30 degrees, 35 degrees, 40 degrees, 45 degrees, 50 degrees, 55 degrees, or 60 degrees, etc.
[0043] The rotor shaft 11 can include one or more helical grooves 113. The helical grooves 113 can be arranged on the inner wall of the cavity 101, and can be recessed from the inner wall of the first cavity 101 towards the outer surface of the rotor shaft 11. The inner wall of the first cavity 101 can be arranged with a plurality of helical grooves 113, and these helical grooves 113 can be spaced apart from each other. One end of the helical grooves 113 can be provided at and in communication with the first opening 111, and the other end of the helical grooves 113 can be in communication with one of the plurality of second openings 121. As shown, Figure 3 As shown, six second openings 121 can be uniformly arranged around the first cavity 101, and four helical grooves 113 can be arranged in communication with four of the six second openings 121. As shown, Figure 2 As shown, the second openings 121 can be located at the end of the helical grooves 113. In one embodiment, the distribution of the second openings 121 and the helical grooves 113 can have other configurations. For example, the plurality of second openings 121 can be non-uniformly arranged on the periphery of the rotor shaft 11, and the number of the second openings 121 and the helical grooves 113 can be equal, or have a ratio different from 1:1. Figure 3The number of different embodiments shown in the figures.
[0044] Figures 4 to 6 Different aspects of one embodiment of the electric machine assembly 1 of the present application are illustrated. The electric machine assembly 1 can include a rotor 10, a stator 20, a housing 30, a first end cover 40, and a second end cover 50, among others. The rotor 10 can be mounted on the rotor shaft 11 described in detail above, and the rotor shaft 11 can be rotatably mounted to the first end cover 40 and the second end cover 50 such that the first housing mounting section 110 and the second housing mounting section 120 fit to the first end cover 40 and the second end cover 50, respectively. The stator 20 can be attached to the housing 30, and the housing 30 can be positioned between the first end cover 40 and the second end cover 50 such that the stator 20 is positioned adjacent to the rotor 10.
[0045] The electric machine assembly 1 can also include a first oil seal member 61. The first oil seal member 61 can be disposed between the first end cover 40 and an outer surface of the first housing mounting section 110 such that the first oil seal member 61, the first end cover 40, and the first housing mounting section 110 collectively enclose the second cavity 82. The first opening 111 of the rotor shaft 11 can be in communication with the second cavity 82, and the first end cover 40 can include an input port 41 in communication with the second cavity 82. As Figure 5 As shown in the figures, the input port 41 can be disposed in the axial direction A-A and face the second cavity 82 and the first opening 111. The first bearing 71 can be disposed in the second cavity 82, for example, journalled on the outside of the first housing mounting section 110 and between the outside of the first housing mounting section 110 and the first end cover 40. Cooling fluid or working fluid can be input into the second cavity 82 through the input port 41 in order to enter the first opening 111 and the first cavity 101. At the same time, the cooling fluid or working fluid can also lubricate and cool the first bearing 71 in the second cavity 82.
[0046] The motor assembly 1 can further include a second oil seal member 62 and a third oil seal member 63. The second oil seal member 62 and the third oil seal member 63 can be disposed between the second end cover 50 and an outer surface of the second housing mounting section 120, such that the second oil seal member 62, the third oil seal member 63, the second end cover 50 and the second housing mounting section 120 collectively enclose a third cavity 83. The second opening 121 of the rotor shaft 11 can be in communication with the third cavity 83. The second bearing 72 can be disposed in the third cavity 83, for example, can be sleeved outside the second housing mounting section 120, and is located between the outside of the second housing mounting section 120 and the second end cover 50. In one embodiment, the second bearing 72 can be positioned between the second oil seal member 62 and the third oil seal member 63. In one embodiment, the second end cover 50 can include an annular protrusion 52, and the protrusion 52 can be disposed between the second bearing 72 and the third oil seal member 63, so as to space the second bearing 72 and the third oil seal member 63 apart. In one embodiment, the rotor shaft 11 can be attached to a gear box, not shown, on one side of the second end cover 50. In this case, the gear box can replace the third oil seal member 63 and occupy the position occupied by the third oil seal member 63 in the middle. In this case, the second bearing 72 can be arranged between the gear box and the second oil seal member 62. Figures 4 to 6
[0047] An output port 51 for working fluid can be disposed on the second end cover 50. The output port 51 can face the third cavity 83. The output port 51 can include a first section 51a extending in the radial direction R-R and a second section 51b extending in the axial direction A-A. The first section 51a can be in direct communication with the second cavity 82, and the second section 51b is in communication with the first section 51a. The first section 51a and the second section 51b can respectively extend through a second predetermined angle on the inner wall of the second end cover 50, so that the output port 51 is formed as part of an annulus. Among them, the second predetermined angle can be set to be between 30 degrees to 120 degrees. For example, 30 degrees, 35 degrees, 40 degrees, 45 degrees, 50 degrees, 55 degrees, 60 degrees, 65 degrees, 70 degrees, 75 degrees, 80 degrees, 85 degrees, 90 degrees, 95 degrees, 100 degrees, 105 degrees, 110 degrees, 115 degrees or 120 degrees, etc. In the embodiment shown, the first section 51a of the output port 51 and the protrusion 52 of the second end cover 50 can be located on substantially the same radial section. The third cavity 83 can be in communication with the output port 51, and the output port 51 can be disposed at the outer periphery of the third cavity 83. Figure 6
[0048] In use, working fluid can be input from the input port 41 of the first end cap 40 and pass through the second cavity 82 to the first bearing 71 and the first opening 111 of the rotor shaft 11 and into the first cavity 101. As the rotor shaft 11 rotates, the working fluid spirals within the first cavity 101 along one or more helical grooves 113 around the axial direction A-A and out of the second opening 121 of the rotor shaft 11. The working fluid then exits the rotor shaft 11 through the second opening 121 and enters the third cavity 83. The working fluid passes through the second bearing 72 at the third cavity 83 and then enters the first section 51a and the second section 51b of the output port 51 on the second end cap 50 and finally exits the output port 51. It is readily understood that the motor assembly of the present application can also include a circulation loop not shown in the figures to deliver the working fluid from the output port 51 back to the input port 41 to complete a working fluid circulation or oil circulation. In this way, the working fluid can circulate within the motor assembly to carry away heat and / or provide lubrication.
[0049] In one embodiment of the present application, the lubricating oil can be used as the cooling fluid and the lubricating oil can flow through the cavities on both ends of the end caps into the bearing housings so that each bearing is lubricated and cooled.
[0050] The rotor shaft and motor assembly of the present application have the advantages of being simple and reliable, easy to implement, convenient to use, etc. and can effectively carry away the heat generated by the motor assembly during operation through the working fluid, thereby reducing the temperature of the motor assembly and improving the reliability.
[0051] The present application is disclosed in the specification, and also enables a person skilled in the art to implement the present application, including manufacturing and using any device or system, selecting appropriate materials, and using any combined method. The scope of the present application is defined by the technical solutions claimed, and includes other examples thought by a person skilled in the art. As long as such other examples include structural elements not different from the literal language of the claimed technical solutions, or such other examples include equivalent structural elements not substantially different from the literal language of the claimed technical solutions, such other examples should be considered to be within the protection scope determined by the claimed technical solutions of the present application.
Claims
1. A rotor shaft, characterized in that, include: The first housing mounting section (110) is configured as a first end cap (40) suitable for mounting to the motor assembly (1); The second housing mounting section (120) is configured to be a second end cap (50) suitable for mounting to the motor assembly (1); A first cavity (101) extends from the first housing mounting section (110) along the axial direction (AA) to the second housing mounting section (120); At least one first opening (111) is provided at the first housing mounting section (110) and communicates the first cavity (101) with the outside of the rotor shaft (11); as well as At least one second opening (121) is provided at the second housing mounting section (120) and communicates the first cavity (101) with the outside of the rotor shaft (11); The inner wall of the first cavity (101) is provided with one or more spiral grooves (113), which extend from the first opening (111) to the second opening (121); and The second opening (121) is configured to extend along the first axis (A1-A1) on the radial section of the rotor shaft (11), and the first axis (A1-A1) forms a first predetermined angle (B1) between the first axis (A1-A1) and the radial direction (RR).
2. The rotor shaft according to claim 1, characterized in that, The first opening (111) is configured to extend in the axial direction (AA).
3. The rotor shaft according to claim 1, characterized in that, A plurality of second openings (121) are uniformly or non-uniformly distributed around the first cavity (101) in a radial cross section, and at least some of the plurality of second openings (121) communicate with the helical groove (113).
4. The rotor shaft according to claim 1, characterized in that, The first predetermined angle (B1) is set between 30 degrees and 60 degrees.
5. The rotor shaft according to any one of claims 1-4, characterized in that, Multiple helical grooves (113) are spaced apart from each other on the inner wall of the first cavity (101); wherein the helical grooves (113) are recessed relative to the inner wall of the first cavity (101) toward the outer surface of the rotor shaft (11).
6. A motor assembly, characterized in that, include: The rotor (10) is constructed to extend along the axial direction (AA); The rotor shaft (11) according to any one of claims 1-5, wherein the rotor (10) is arranged around the rotor shaft (11); Stator (20), which is arranged on the outer periphery of the rotor (10); A housing (30) that houses the stator (20) and the rotor (10), the stator (20) being attached to the housing (30); A first end cap (40) is attached to the housing (30), and the first housing mounting section (110) of the rotor shaft (11) is rotatably attached to the first end cap (40); and A second end cap (50) is attached to the housing (30), and the second housing mounting section (120) of the rotor shaft (11) is rotatably attached to the second end cap (50).
7. The motor assembly according to claim 6, characterized in that, The device includes a first oil seal (61) and a first bearing (71), which are arranged between the outer periphery of the first housing mounting section (110) and the first end cap (40). The first oil seal (61), the first housing mounting section (110), and the first end cap (40) together surround a second cavity (82), and the first bearing (71) is located within the second cavity (82). The first opening (111) communicates with the first cavity (101), and the first end cap (40) includes an inlet (41) for coolant, which communicates with the first cavity (101).
8. The motor assembly according to claim 7, characterized in that, The device includes a second oil seal (62) and a second bearing (72), the second oil seal (62) and the second bearing (72) being arranged between the outer periphery of the second housing mounting section (120) and the second end cap (50), and the second oil seal (62), the second housing mounting section (120) and the second end cap (50) together surround a third cavity (83), and the second bearing (72) is located within the second cavity (82); wherein, the second opening (121) communicates with the third cavity (83), and the second end cap (50) includes an outlet (51) for coolant, the outlet (51) communicating with the third cavity (83).
9. The motor assembly according to claim 8, characterized in that, It also includes a third oil seal (63) arranged between the outer periphery of the second housing mounting section (120) and the second end cap (50), such that the second bearing (72) is located between the second oil seal (62) and the third oil seal (63). The second end cap (50) also includes an annular protrusion (52) disposed between the second bearing (72) and the third oil seal (63).
10. The motor assembly according to claim 8 or 9, characterized in that, The output port (51) includes a first segment (51a) extending in the radial direction (RR) and a second segment (51b) extending in the axial direction (AA), the first segment (51a) communicating with the second cavity (82) and the second segment (51b) communicating with the first segment (51a); in the radial plane, the first segment (51a) and the second segment (51b) extend on the inner wall of the second end cap (50) through a second predetermined angle, such that the output port (51) is formed as part of an annulus, wherein the second predetermined angle is set between 30 degrees and 120 degrees.