Oil passage structure of motor rotor and motor device

Abstract

The application discloses a motor rotor oil passage structure and a motor device. The motor rotor oil passage structure comprises a shell, a first oil inlet hole is formed in the shell, a hollow shaft penetrates the shell rotatably, the hollow shaft has an inner cavity and a second oil inlet hole which is communicated with the inner cavity, the first oil inlet hole is used for being communicated with the second oil inlet hole, at least one pair of pressure reduction devices are sleeved between the hollow shaft and the shell, and the second oil inlet hole is located between the pair of pressure reduction devices, the pressure reduction device comprises a mounting seat which is sleeved outside the hollow shaft and a buffer ring which is embedded in the mounting seat, a pressure relief groove is formed in the buffer ring, and the buffer ring is in clearance fit with the hollow shaft. The motor rotor can be oiled at high speed, torque can be transmitted, the cost is low, and the universality is high.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of motor testing, in particular to a motor rotor oil feeding structure and a motor device. BACKGROUND

[0002] In order to realize the testing of high-speed motors, the rotor and the stator of the motor need to be fed with oil. Since the stator is in a static state, the oil feeding difficulty is low. However, the rotor rotates at a high speed in a working state, and the highest rotating speed can reach 40,000 rpm. Under the condition of high-speed rotation, the centrifugal force generated by high-speed rotation hinders the lubricating oil from entering the motor rotor shaft. In order to overcome the centrifugal force, a high oil supply pressure is required, and the highest oil supply pressure can reach 40 bar. Moreover, due to high-speed rotation, the linear speed at the sealing position is extremely high, and the highest linear speed can reach 85 m / s. In addition, torque needs to be transmitted during the experiment, and the maximum torque can reach 480 Nm. However, the current motor rotor oil feeding devices on the market are mainly used for low-speed oil feeding, and there are almost no devices for feeding oil to high-speed motor rotors. It is difficult to feed oil to high-speed motor rotors. The main technical difficulties are how to successfully feed oil and how to seal after feeding oil. Under the condition of high-speed rotation, the internal pressure of the rotor is high, and the oil feeding difficulty is high. Under the condition of high-speed rotation, the linear speed and pressure at the sealing position are high, resulting in high oil feeding and sealing difficulty. During the oil feeding process under high-speed rotation, a large amount of leakage is usually caused, which leads to a decrease in oil pressure and failure of the rotor oil feeding. Under the condition of high linear speed and high pressure, the current high-speed rotor oil feeding problem needs to be solved urgently. SUMMARY

[0003] The purpose of the present application is to provide a motor rotor oil feeding structure and a motor device, which can realize oil feeding and torque transmission for high-speed rotating motor rotors, and have low cost and high universality.

[0004] To solve the above technical problems, the embodiments of the present application provide a motor rotor oil feeding structure, which comprises:

[0005] A housing, wherein a first oil inlet hole is formed in the housing;

[0006] A hollow shaft, wherein the hollow shaft penetrates the housing rotatably, the hollow shaft has an inner cavity, and a second oil inlet hole is in communication with the inner cavity; the first oil inlet hole is used to communicate with the second oil inlet hole;

[0007] At least one pair of pressure reduction devices, which are sleeved between the hollow shaft and the housing, and the second oil inlet hole is located between a pair of the pressure reduction devices; the pressure reduction device comprises a mounting seat sleeved outside the hollow shaft and a buffer ring embedded in the mounting seat.

[0008] In an embodiment, the buffer ring is in clearance fit with the hollow shaft.

[0009] The buffer ring has an outer ring surface, an inner ring surface facing the hollow shaft, a first mounting surface connecting the inner ring surface and the outer ring surface, the first mounting surface faces the mating surface of the mounting seat, the first mounting surface is provided with the pressure relief groove, and the opening of the pressure relief groove faces the direction where the first oil inlet hole is located.

[0010] In an embodiment, the pressure relief groove has a plurality of pressure relief grooves, and the plurality of pressure relief grooves are uniformly arranged on the first mounting surface.

[0011] In an embodiment, the mounting seat is provided with a pressure relief hole; the pressure relief hole penetrates the side wall of the mounting seat and avoids the buffer ring.

[0012] In an embodiment, the pressure relief hole has a plurality of pressure relief holes, and the plurality of pressure relief holes are uniformly arranged on the mounting seat.

[0013] In an embodiment, the mounting seat is provided with a plurality of mounting grooves arranged along the axis direction of the mounting seat, and each of the mounting grooves is provided with the buffer ring.

[0014] In the axis direction of the hollow shaft, the buffer ring is closer to the first oil inlet hole and the second oil inlet hole than the pressure relief hole.

[0015] In an embodiment, the second oil inlet hole is an inclined waist-shaped hole, the extension direction of the inclined waist-shaped hole is inclined to the radial direction of the hollow shaft; the second oil inlet hole has a plurality of second oil inlet holes, and the plurality of second oil inlet holes are uniformly arranged on the hollow shaft.

[0016] In an embodiment, the oil supply structure further comprises at least one pair of sealing members, the sealing members are sleeved between the hollow shaft and the housing, and the pressure relief device is located between the pair of sealing members.

[0017] The inner ring surface of the sealing member has a plurality of annular cavity grooves, and the plurality of annular cavity grooves are arranged along the axis direction of the sealing member; the sealing member and the hollow shaft have a throttling gap.

[0018] In an embodiment, the oil supply structure further comprises an oil supply ring sleeved on the hollow shaft, the oil supply ring is fixed relative to the housing, the oil supply ring is arranged between the pair of pressure relief devices, and the oil supply ring is provided with a third oil inlet hole communicating with the first oil inlet hole.

[0019] The embodiment of the present application also provides an electric machine device, comprising an electric machine and the oil supply structure as described in any one of the above embodiments, and the hollow shaft of the oil supply structure is connected with the rotor of the electric machine.

[0020] The embodiment of the present application is relative to the prior art, by setting the pressure reducing device, the pressure reducing device includes the mounting seat and the buffer ring, when the hollow shaft is driven by the rotor of the motor to rotate at high speed, the pressure oil needs to enter the second oil inlet through the first oil inlet, and then enter the inner cavity. Before the pressure oil contacts the seal, it first passes through the buffer ring, which is in clearance fit with the hollow shaft. During operation, the buffer ring is activated by pressure and changes to a compressed state, bearing pressure while releasing a certain back pressure through the pressure relief groove to reduce the oil pressure to a pressure that the oil seal can withstand, thereby meeting the use requirements of the oil seal and avoiding leakage. Oil can also enter the second oil inlet through the first oil inlet, and then enter the inner cavity of the hollow shaft, realizing oil passage of the high-speed motor rotor. At the same time, the oil passage structure is compact in structure, occupies small space, can conveniently meet the testing of different measured parts, reduces cost, and most of the parts can be reused, improving the reusability and compatibility of the oil passage structure. BRIEF DESCRIPTION OF DRAWINGS

[0021] One or more embodiments are illustrated by way of example in the figures that form a part of this patent document, these example illustrations do not limit the embodiments, elements having the same reference numbers in the figures represent similar elements, unless otherwise indicated, the figures in the drawings do not constitute a proportional limitation.

[0022] Figure 1 is a perspective view of the oil passage structure according to an embodiment of the present application;

[0023] Figure 2 is a sectional view of the oil passage structure according to an embodiment of the present application;

[0024] Figure 3 is Figure 2 is a partial enlarged view of A in the figure;

[0025] Figure 4 is a perspective view of the hollow shaft according to an embodiment of the present application;

[0026] Figure 5 is a sectional view of the hollow shaft according to an embodiment of the present application;

[0027] Figure 6 is a structural schematic view of the mounting seat according to an embodiment of the present application;

[0028] Figure 7 is a structural schematic view of the buffer ring according to an embodiment of the present application;

[0029] Figure 8 is a sectional view of the pressure reducing device according to an embodiment of the present application;

[0030] Figure 9 is a structural schematic view of the seal according to an embodiment of the present application;

[0031] Figure 10 This is a cross-sectional view of the seal according to an embodiment of the present invention;

[0032] Reference numerals: 100, oil passage structure; 1, housing; 10, first oil inlet; 2, hollow shaft; 20, second oil inlet; 21, inner cavity; 3, pressure reducing device; 31, mounting base; 310, pressure relief hole; 311, mating surface; 32, buffer ring; 320, pressure relief groove; 321, outer annular surface; 322, inner annular surface; 323, first mounting surface; 4, seal; 40, annular cavity groove; 5, throttling gap; 6, oil supply ring; 60, third oil inlet. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the various embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been presented in the various embodiments of the present invention to enable the reader to better understand this application. However, the technical solutions claimed in this application can be implemented even without these technical details and various changes and modifications based on the following embodiments.

[0034] In the following description, certain specific details are set forth for the purpose of illustrating various disclosed embodiments in order to provide a thorough understanding of the various disclosed embodiments. However, those skilled in the art will recognize that embodiments may be practiced without one or more of these specific details. In other instances, well-known apparatuses, structures, and techniques associated with this application may not have been shown or described in detail to avoid unnecessarily obscuring the description of the embodiments.

[0035] Unless the context requires otherwise, throughout the specification and claims, the word “comprising” and its variations, such as “including” and “having”, shall be understood to have an open, inclusive meaning, that is, to be interpreted as “including, but not limited to”.

[0036] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings to provide a clearer understanding of the purpose, features, and advantages of the present invention. It should be understood that the embodiments shown in the drawings are not intended to limit the scope of the present invention, but are merely illustrative of the essential spirit of the technical solution of the present invention.

[0037] Throughout this specification, references to "an embodiment" or "an embodiment" indicate that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Therefore, the appearance of "in an embodiment" or "an embodiment" in various places throughout the specification does not necessarily refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic may be combined in any manner in one or more embodiments.

[0038] The singular forms “a” and “the” used in this specification and the appended claims include plural references unless otherwise expressly stated herein. It should be noted that the term “or” is generally used to mean “and / or” unless otherwise expressly stated herein.

[0039] In the following description, in order to clearly demonstrate the structure and working method of the present invention, a number of directional terms will be used. However, terms such as "front", "back", "left", "right", "outside", "inside", "outward", "inward", "up", and "down" should be understood as convenient terms and not as limiting terms.

[0040] Embodiments of the present invention are described below with reference to the accompanying drawings.

[0041] One embodiment of the present invention relates to an oil passage structure 100 for an electric motor rotor. The oil passage structure 100 is used to connect the rotor of the electric motor, supply oil to the rotor rotating at high speed, and transmit torque. Figure 1 and Figure 2 As shown, Figure 2 Arrow B indicates the oil inlet direction. The oil passage structure 100 includes a housing 1, a hollow shaft 2, and at least one pair of pressure-reducing devices 3. A first oil inlet hole 10 is provided on the housing 1. The hollow shaft 2 rotatably passes through the housing 1 and has an inner cavity 21, and a second oil inlet hole 20 communicating with the inner cavity 21. The first oil inlet hole 10 communicates with the second oil inlet hole 20. At least one pair of pressure-reducing devices 3 are sleeved between the hollow shaft 2 and the housing 1, and the second oil inlet hole 20 is located between the pair of pressure-reducing devices 3. The pressure-reducing device 3 includes: a mounting base 31 sleeved outside the hollow shaft 2, and a buffer ring 32 embedded in the mounting base 31. The buffer ring 32 has a pressure relief groove 320, and the buffer ring 32 and the hollow shaft 2 can be clearance-fitted. The rotor of the motor drives the hollow shaft 2 to rotate relative to the pressure reducing device 3 and the housing 1. The pressure reducing device 3 can achieve sealing to prevent oil from leaking between the hollow shaft 2 and the housing 1. Oil enters through the first oil inlet hole 10 and then enters the second oil inlet hole 20 until it reaches the cavity.

[0042] In view of the size limitation of the oil passing tool and the universality and installation portability in response to different prototypes, the contact type seal is selected to select the oil seal for sealing, and the pressure reducing device 3 is selected to ensure that the high linear speed is met. In this case, the pressure that the oil seal can withstand is very low, only about 0.5 bar, and cannot withstand the pressure required by the high-speed oil passing. By setting the pressure reducing device 3, the pressure reducing device 3 includes a mounting seat 31 and a buffer ring 32. When the hollow shaft 2 is driven by the rotor of the motor to rotate at high speed, the pressure oil needs to pass through the first oil inlet hole 10 to enter the second oil inlet hole 20, and then enter the inner cavity 21. Before the pressure oil contacts the seal, it first passes through the buffer ring 32, which is in clearance fit with the hollow shaft 2. During operation, the buffer ring 32 will be compressed to withstand pressure, and at the same time, a certain back pressure will be released through the pressure relief groove 320 to reduce the oil pressure to the pressure that the oil seal can withstand, thereby meeting the use requirements of the oil seal and avoiding leakage. Oil can also pass through the first oil inlet hole 10 to enter the second oil inlet hole 20, and then enter the inner cavity 21 of the hollow shaft 2 to realize high-speed motor rotor oil passing. At the same time, the oil passing structure 100 is compact in structure and occupies small space, which can conveniently meet the testing of different test pieces, reduce cost, and most of the parts can be reused to improve the reusability and compatibility of the oil passing structure 100. The existing oil passing device is highly customized and cannot conveniently meet the testing of different test pieces. The cost of testing is high, the design and manufacture of the oil passing device consume a long time, and the output rate is low.

[0043] Under the premise of meeting the high-speed motor test, the axial distance needs to be as short as possible. According to the rotor dynamics analysis, the length of the hollow shaft 2 should be controlled within 140 mm. Otherwise, during the speed-up process, the critical speed will be passed, vibration problems will occur, and it is not conducive to the hollow shaft 2 to reach a higher speed. The design of the pressure reducing device 3 can make the overall structure more compact, thereby shortening the axial length and optimizing the rotor dynamics analysis.

[0044] Further, as shown in Figure 7 , the buffer ring 32 has an outer ring surface 321, an inner ring surface 322 facing the hollow shaft 2, a first mounting surface 323 connecting the inner ring surface 322 and the outer ring surface 321, the first mounting surface 323 facing the mating surface 311 of the mounting seat 31, and the first mounting surface 323 being provided with a pressure relief groove 320, the opening of the pressure relief groove 320 facing the direction of the first oil inlet hole 10.

[0045] Further, the pressure relief groove 320 has a plurality of pressure relief grooves 320, which are uniformly arranged on the first mounting surface 323.

[0046] In addition, as shown in Figure 6 , the mounting seat 31 is provided with a pressure relief hole 310, the pressure relief hole 310 penetrates the side wall of the mounting seat 31, and avoids the buffer ring 32.

[0047] Further, the pressure relief holes 310 are provided in plurality and arranged uniformly on the mounting seat 31.

[0048] Further, as shown in Figure 3 , the mounting seat 31 is provided with mounting grooves arranged along the axial direction of the mounting seat 31, and each mounting groove is provided with a buffer ring 32. In the axial direction of the hollow shaft 2, the buffer ring 32 is closer to the first oil inlet hole 10 and the second oil inlet hole 20 than the pressure relief hole 310.

[0049] Specifically, taking the case that the pressure relief groove 320 is provided with four pressure relief holes 310 as an example, in operation, the buffer ring 32 is made of elastic material, and the buffer ring 32 is in contact with the matching surface 311 through a small gap fit, and is activated only by the pressure difference acting on the buffer ring 32. In operation, the buffer ring 32 is compressed to withstand pressure, and at the same time releases a certain back pressure through the pressure relief groove 320. At the same time, the mounting seat 31 is provided with uniformly distributed pressure relief holes 310 to further reduce the back pressure released from the buffer ring 32 through the pressure relief groove 320, thereby achieving the effect of reducing oil pressure. The pressure reducing device reduces the pressure to the pressure that the oil seal can withstand, thereby meeting the use requirements of the oil seal and avoiding leakage.

[0050] The number of pressure relief grooves 320 and pressure relief holes 310 in the embodiment can be set according to actual needs.

[0051] In addition, as shown in Figure 4 and Figure 5 , the second oil inlet hole 20 is a diagonal waist-shaped hole, and the extension direction of the diagonal waist-shaped hole is inclined to the radial direction of the hollow shaft 2. The second oil inlet hole 20 is provided in plurality and arranged uniformly on the hollow shaft 2. The first oil inlet hole 10 can be arranged at the middle part of the length direction of the housing 1. The oil enters the second oil inlet hole 20 through the middle part, and since the second oil inlet hole 20 is a diagonal waist-shaped hole, oil stirring occurs during the rotation of the hollow shaft 2. Through simulation analysis and actual experiment, the oil flow effect can be enhanced. The angle of the inclined direction of the diagonal waist-shaped hole can be set according to actual needs.

[0052] Further, as shown in Figure 2 , Figure 3 , the oil flow structure 100 further comprises at least one pair of sealing members 4, the sealing members 4 are sleeved between the hollow shaft 2 and the housing 1, and the pressure reducing device 3 is located between the pair of sealing members 4. As shown in Figure 9 , Figure 10As shown, the inner annular surface 322 of the seal 4 has a plurality of annular cavity grooves 40 arranged along the axial direction of the seal 4. The seal 4 and the hollow shaft 2 have a throttling gap 5. After oil supply, the pressure oil enters the hollow shaft 2 through the second oil inlet hole 20, and the transition from radial oil supply to axial oil supply is completed. The remaining oil is sealed by the outer oil seal after pressure reduction by the two side pressure reduction devices 3. Considering that the oil seal has a certain leakage amount, the outermost side is provided with the seal 4, which can be an oil throwing baffle ring. The oil throwing baffle ring adopts a labyrinth seal structure. The seal 4 forms a series of regular throttling gaps 5 and annular cavity grooves 40 with a group of sealing teeth. When the gas flows through the gap formed by the sealing teeth and the surface of the hollow shaft 2, the pressure oil is subjected to throttling, the pressure and temperature of the pressure oil decrease, and the flow rate increases. After passing through the gap, a larger cavity is formed between the two sealing teeth. As shown, the pressure oil increases in volume in the cavity, the speed decreases, and a vortex flow is formed, generating a certain amount of heat. Therefore, the temperature of the pressure oil in the cavity returns to that before throttling. The pressure oil is subjected to throttling and expansion once every time it passes through a gap and a subsequent larger annular cavity groove 40. With the increase in the number of pressure oil flowing through the gap and the annular cavity groove 40, and the decrease in the gap value, the flow rate and pressure drop of the pressure oil become larger and larger. When the pressure drops to approximately the back pressure, the pressure oil no longer continues to flow out, thereby achieving sealing and reducing leakage of the pressure oil. The hollow shaft 2 is designed in a manner facilitating installation of the oil seal and the pressure reduction structure. When different motors are replaced, the spline parameters of the motor may change. At this time, the hollow shaft 2 can be reprocessed according to the new spline parameters, so as to match the new motor, thereby making the overall versatility stronger. During actual installation, the special design of the outer side of the hollow shaft 2, i.e., the shaft head chamfer and the round corner, ensures correct installation of the oil seal.

[0053] In addition, as shown in the drawings, Figure 2 The oil supply structure 100 further includes an oil supply ring 6 sleeved on the hollow shaft 2, the oil supply ring 6 being fixed relative to the housing 1, and the oil supply ring 6 being arranged between the pair of pressure reduction devices 3. The oil supply ring 6 is provided with a third oil inlet hole 60 communicating with the first oil inlet hole 10. When the hollow shaft 2 rotates to a position where the second oil inlet hole 20 corresponds to the third oil inlet hole 60, the pressure oil enters the third oil inlet hole 60 from the second oil inlet hole 20.

[0054] In the embodiment, the housing 1, the hollow shaft 2, the oil supply ring 6 and the seal 4 can be sealed by a sealing ring.

[0055] Another embodiment of the application relates to a motor device, which comprises a motor and an oil supply structure as in the above-mentioned embodiments, and the hollow shaft of the oil supply structure is connected to the rotor of the motor.

[0056] It can be found that the embodiment is a system embodiment corresponding to the first embodiment, and the embodiment can be implemented in cooperation with the first embodiment. The related technical details mentioned in the first embodiment are still valid in the embodiment, and in order to reduce repetition, they will not be described here. Correspondingly, the related technical details mentioned in the embodiment can also be applied in the first embodiment.

[0057] The preferred embodiments of the present application have been described in detail above, but it should be understood that aspects of the embodiments can be modified to employ aspects, features and concepts of various patents, applications and publications to provide additional embodiments if desired.

[0058] In view of the foregoing detailed description of embodiments, modifications and changes can be suggested by those skilled in the art, but it is the intention that the embodiments in accordance with the principles of the application can be practiced otherwise than as specifically described. In general, the terms used are intended to be construed in a descriptive sense and not in a limiting sense.

[0059] Those skilled in the art can understand that the above-mentioned embodiments are specific embodiments for implementing the present application, and in actual application, various changes can be made in form and details without departing from the spirit and scope of the present application.

Claims

1. An oil passage structure of a rotor of an electric motor, characterized by comprising: The application relates to a structure for oil feeding of a motor, which comprises the following parts: a housing, wherein a first oil inlet hole is formed on the housing; a hollow shaft, which is rotatably penetrated through the housing, wherein the hollow shaft has an inner cavity and a second oil inlet hole which is communicated with the inner cavity; the first oil inlet hole is used to communicate with the second oil inlet hole; at least one pair of pressure reducing devices, which are sleeved between the hollow shaft and the housing, and the second oil inlet hole is located between the pair of pressure reducing devices; the pressure reducing device comprises a mounting base which is sleeved on the hollow shaft and a buffer ring which is embedded in the mounting base, and a pressure relief groove is formed on the buffer ring; the buffer ring is in clearance fit with the hollow shaft; the buffer ring has an outer ring surface, an inner ring surface which faces the hollow shaft, a first mounting surface which connects the inner ring surface and the outer ring surface, the first mounting surface faces a mating surface of the mounting base, and the pressure relief groove is formed on the first mounting surface, and the opening of the pressure relief groove faces the direction of the first oil inlet hole; the pressure relief groove has a plurality of pressure relief grooves which are uniformly arranged on the first mounting surface; a pressure relief hole is formed on the mounting base; the pressure relief hole penetrates through the side wall of the mounting base and avoids the buffer ring.

2. The oil passage structure of an electric motor rotor according to claim 1, characterized by the pressure relief hole has a plurality of pressure relief holes which are uniformly arranged on the mounting base.

3. The oil passage structure of an electric motor rotor according to claim 2, characterized by a plurality of mounting grooves are formed on the mounting base along the axial direction of the mounting base, and each of the mounting grooves has the buffer ring; in the axial direction of the hollow shaft, the buffer ring is closer to the first oil inlet hole and the second oil inlet hole than the pressure relief hole.

4. The oil passage structure of an electric motor rotor according to claim 1, characterized by the second oil inlet hole is a slanting waist-shaped hole, the extending direction of the slanting waist-shaped hole is inclined to the radial direction of the hollow shaft; the second oil inlet hole has a plurality of second oil inlet holes which are uniformly arranged on the hollow shaft.

5. The oil passage structure of an electric motor rotor according to claim 1, characterized by the oil feeding structure further comprises at least one pair of sealing members, the sealing members are sleeved between the hollow shaft and the housing, and the pressure reducing devices are located between the pair of sealing members; the inner ring surface of the sealing member has a plurality of annular cavity grooves which are arranged along the axial direction of the sealing member; the sealing member has a throttling gap with the hollow shaft.

6. The oil passage structure of an electric motor rotor according to claim 1, characterized by the oil feeding structure further comprises an oil supply ring which is sleeved on the hollow shaft, the oil supply ring is fixed relative to the housing, and the oil supply ring is arranged between the pair of pressure reducing devices; a third oil inlet hole which is communicated with the first oil inlet hole is formed on the oil supply ring.

7. An electric machine arrangement, characterized in that The application relates to a structure for oil feeding of a motor, which comprises the following parts: a motor and the oil feeding structure as claimed in any one of claims 1-6, wherein the hollow shaft of the oil feeding structure is connected with the rotor of the motor.

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