CN107231049B

CN107231049B - Liquid cooling structure of motor rotor

Info

Publication number: CN107231049B
Application number: CN201710470648.9A
Authority: CN
Inventors: 夏继; 张诗香; 张胜川; 李鹏
Original assignee: NIO Co Ltd
Current assignee: NIO Co Ltd
Priority date: 2017-06-20
Filing date: 2017-06-20
Publication date: 2023-07-07
Anticipated expiration: 2037-06-20
Also published as: WO2018233319A1; TW201906286A; TWM570352U; CN107231049A

Abstract

The invention belongs to the field of motors, and particularly provides a liquid cooling structure of a motor rotor. The invention aims to solve the problem that the cooling structure of the motor rotor in the prior art is easy to cause cooling water to enter the motor to damage the motor. For this purpose, the rotor liquid cooling structure of the invention comprises a rotating shaft provided with a rotating shaft hole, an end cover for supporting the rotating shaft and a cooling water pipe, wherein one end of the cooling water pipe is connected with the end cover, and the other end of the cooling water pipe extends into the rotating shaft hole. Further, one end of the rotating shaft far away from the end cover is provided with an air hole communicated with the rotating shaft hole. The rotor liquid cooling structure can enable water to circulate in the cooling water pipe, and indirectly absorb the heat of the rotor by absorbing the heat of the cooling water pipe. Therefore, water in the rotor liquid cooling structure can always circulate in the cooling water pipe, and cannot enter the motor to cause corrosion and damage to the inside of the motor.

Description

Liquid cooling structure of motor rotor

Technical Field

The invention belongs to the field of motors, and particularly provides a liquid cooling structure of a motor rotor.

Background

High power density motors often come with very high temperature rise during operation, and in order to avoid damage to the motor due to overheating of the rotor, cooling mechanisms are typically provided on the rotor to reduce the temperature rise of the motor rotor. At present, a mode of forming a blind hole in a motor rotating shaft and enabling cooling water to directly contact with the inner wall of the blind hole of the rotating shaft so as to absorb heat of a rotor through the rotating shaft is generally adopted. However, this cooling requires a rotary seal to seal the rotor to prevent cooling water from entering the motor interior. However, the reliability of the rotary seal is still a great problem at the present stage, and the phenomenon that the motor is damaged due to water leakage is easy to occur.

Accordingly, there is a need in the art for a new rotor cooling structure that addresses the above-described problems.

Disclosure of Invention

In order to solve the above-mentioned problems in the prior art, that is, in order to solve the problem that in the prior art, cooling water is easy to enter into the motor to damage the motor in the cooling structure of the motor rotor, the invention provides a motor rotor liquid cooling structure, the motor includes a casing, an end cover, a stator, a rotor and a rotating shaft, the end cover is provided with a first channel and a second channel, the rotating shaft is internally provided with a rotating shaft hole along the axial direction, and the motor rotor liquid cooling structure is characterized in that: a mounting end fixed to an end of the motor; and a cooling end capable of being accommodated in the rotation shaft hole, the cooling end being formed with a cooling passage; wherein the cooling channel communicates with the first channel and the second channel through the mounting end.

In the above-mentioned preferred technical scheme of electric motor rotor liquid cooling structure, the cooling end includes first pipeline and cover locate the second pipeline in the first pipeline outside, just the first pipeline keep away from the one end of installation end with the second pipeline intercommunication, the inner chamber of first pipeline and by first pipeline with the ring chamber between the second pipeline forms cooling channel.

In the preferred technical scheme of the motor rotor liquid cooling structure, the mounting end is provided with a first through hole and a second through hole, the first through hole can be communicated with the inner cavity and the first channel, and the second through hole can be communicated with the annular cavity and the second channel.

In the preferred technical scheme of the motor rotor liquid cooling structure, the mounting end and the cooling end are integrally formed.

In the preferred technical scheme of the motor rotor liquid cooling structure, a heat conducting medium is filled in the part, between the second pipeline and the rotating shaft hole, in the rotating shaft hole.

In the preferred technical scheme of the motor rotor liquid cooling structure, ventilation holes are formed in the rotating shaft, and the heat conducting medium is filled into the rotating shaft holes through the ventilation holes.

In the preferred technical scheme of the rotor liquid cooling structure, the heat conducting medium is modified silicone oil.

In the preferable technical scheme of the motor rotor liquid cooling structure, the ventilation holes are provided with ventilation valves.

In the preferable technical scheme of the motor rotor liquid cooling structure, the air ventilation valve is a one-way air ventilation valve.

In the above preferred technical solution of the motor rotor liquid cooling structure, the motor rotor liquid cooling structure further includes a shunt, and the mounting end is fixedly connected with the end of the motor through the shunt.

As can be appreciated by those skilled in the art, in the preferred embodiment of the present invention, the cooling end of the rotor liquid cooling structure having the cooling channel is disposed in the shaft hole of the shaft, so that heat generated by the rotor during the operation of the motor can be conducted to the cooling end. Through fixing the installation end of rotor liquid cooling structure at the tip of motor for the cooling channel can be with first passageway and the second passageway intercommunication on the motor end cover, and then the coolant liquid can take away the heat that the cooling end absorbed in the pivot. Therefore, the cooling liquid (such as water) in the rotor liquid cooling structure can always circulate in the rotor liquid cooling structure, and cannot enter the motor to cause corrosion and damage to the inside of the motor.

Further, the air holes in the rotating shaft are used for injecting modified silicone oil into the rotating shaft holes, and the annular cavity between the inner wall of the rotating shaft holes and the outer wall of the cooling end is filled with the modified silicone oil, so that the heat exchange rate between the rotating shaft and the cooling end can be effectively improved, the heat dissipation speed of the motor rotor is improved, and the service life of the motor is prolonged.

Drawings

FIG. 1 is a cross-sectional view of a motor rotor liquid cooling structure according to an embodiment of the present invention;

fig. 2 is a schematic diagram illustrating the effect of a cooling water pipe of a liquid cooling structure of a motor rotor according to an embodiment of the present invention.

List of reference numerals:

1. an end cap; 11. a first channel; 12. a second channel; 2. a rotor; 3. a rotating shaft; 31. a rotation shaft hole; 32. ventilation holes; 33. a threaded hole; 4. a cooling water pipe; 41. a first pipe; 411. an inner cavity; 42. a second pipe; 421. an annular cavity; 43. a mounting end; 431. a first through hole; 432. a second through hole; 433. a mounting hole; 434. an annular groove; 5. a shunt; 51. a first nozzle; 52. a second nozzle; 6. a first seal ring; 7. a second seal ring; 8. and a third sealing ring.

Detailed Description

Preferred embodiments of the present invention are described below with reference to the accompanying drawings. It should be understood by those skilled in the art that these embodiments are merely for explaining the technical principles of the present invention, and are not intended to limit the scope of the present invention. For example, although the preferred embodiment of the present invention is described by taking the rotor liquid cooling structure of the motor as an example with reference to the accompanying drawings, it is obvious that the rotor liquid cooling structure of the present invention can be applied to other products having a rotor structure, such as a hydraulic oil pump, and those skilled in the art can adjust the rotor liquid cooling structure as required to adapt to specific applications, and the adjusted technical solution still falls within the scope of protection of the present invention.

It should be noted that, in the description of the present invention, terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," "outer," and the like indicate directions or positional relationships based on the directions or positional relationships shown in the drawings, which are merely for convenience of description, and do not indicate or imply that the apparatus or elements must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

Furthermore, it should be noted that, in the description of the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention can be understood by those skilled in the art according to the specific circumstances.

As shown in fig. 1, the motor of the present invention mainly includes a casing (not shown), a shunt 5, a stator (not shown), a rotor 2, and a rotating shaft 3. The motor rotor liquid cooling structure mainly comprises a rotating shaft 3, a cooling water pipe 4 and a flow divider 5. Wherein the mounting end 43 of the cooling water pipe 4 (the lower end of the cooling water pipe 4 in fig. 1) is fixedly connected with the flow divider 5, and the cooling end of the cooling water pipe 4 (the upper end portion of the cooling water pipe 4 except the mounting end 43 in fig. 1) is disposed in the rotating shaft 3. Wherein the shunt 5 is fixedly mounted to the inside of the end of the housing, e.g. to the motor end cap 1. In particular, the lower end of the cooling water pipe 4 (see fig. 2) in fig. 1 is fixedly connected to the flow divider 5, preferably by bolting between the cooling water pipe 4 and the flow divider 5, or the cooling water pipe 4 may be fixed to the flow divider 5 by any other and possible connection, such as welding, by a person skilled in the art. In addition, the cooling water pipe 4 and the flow divider 5 can be integrally formed as a single structure by one skilled in the art.

Further, as shown in fig. 1, a shaft hole 31 is provided at the lower end of the shaft 3 in the axial direction, and a ventilation hole 32 is provided at the upper end of the shaft 3 in fig. 1. Referring to fig. 1 and 2, most of the upper side of the cooling water pipe 4 can extend into the rotation shaft hole 31, and in the assembled state, a certain gap is formed between the outer wall of the cooling water pipe 4 and the inner wall of the rotation shaft hole 31. Further, a heat-conducting medium such as modified silicone oil is filled into the gap through the ventilation holes 32 to rapidly transfer heat generated from the rotor 2 to the cooling water pipe 4 during operation of the motor, effectively improving a heat conduction rate. Further, in order to prevent the modified silicone oil in the rotation shaft hole 31 from overflowing from the air vent 32 during the use of the motor, the upper end of the air vent 32 in fig. 1 is provided with a screw hole 33 for installing a one-way air vent valve (not shown). The unidirectional ventilation valve can also keep the pressure in the rotating shaft hole 31 the same as the external atmospheric pressure all the time, and the modified silicone oil is prevented from being extruded out of the rotating shaft hole 31 due to the overhigh pressure. The unidirectional ventilation valve can be any device structure which can be thought of and implemented by a person skilled in the art, such as a bolt with a pin hole in the axle.

It should be noted that, on the premise of ensuring the heat conduction rate between the rotating shaft 3 and the cooling water pipe 4, a person skilled in the art can also appropriately adjust the size of the gap between the inner wall of the rotating shaft 3 and the outer wall of the cooling water pipe 4 according to the requirement, and obviously the adjusted technical scheme still falls into the protection scope of the invention. It should be noted that, under the premise of ensuring sealability, thermal conductivity, foam resistance and easy filling, those skilled in the art can also use other heat conducting media instead of modified silicone oil, for example, hydraulic oil.

As shown in fig. 1 and 2, the cooling water pipe 4 mainly includes a mounting end 43 and a cooling end (an upper end portion of the cooling water pipe 4 excluding the mounting end 43 in fig. 1). Wherein, the installation end 43 is fixedly connected with the diverter 5 through a bolt, and the cooling end can be completely accommodated in the rotating shaft hole 31 under the condition that a gap exists between the outer wall of the cooling water pipe 4 and the inner wall of the rotating shaft hole 31. Further, the cooling end includes a first pipe 41 and a second pipe 42, and lower ends of the first pipe 41 and the second pipe 42 are fixedly connected to the mounting end 43, preferably, the first pipe 41, the second pipe 42 and the mounting end 43 are integrally formed, or one skilled in the art may fix the first pipe 41 and the second pipe 42 to the mounting end 43 by other connection means, for example, screw connection or welding the first pipe 41 and the second pipe 42 to the mounting end 43, as needed.

As shown in fig. 1, the first duct 41 is located in the second duct 42, and the upper end of the first duct 41 communicates with the second duct 42 such that the inner cavity 411 of the first duct 41 and the annular cavity 421 between the first duct 41 and the second duct 42 constitute a cooling passage. In addition, the annular chamber 421 may be configured as an annular chamber of other structures, such as a spiral type annular chamber along the axial direction of the first water pipe 41, as required by those skilled in the art.

As shown in fig. 1, the end cap 1 is provided with a first passage 11 and a second passage 12. The flow divider 5 is provided with a first water gap 51 and a second water gap 52, and the first water gap 51 can communicate with the first passage 11 and the second water gap 52 can communicate with the second passage 12 when the flow divider 5 is fixed to the end cap 1. In one possible embodiment, the housing is provided with a spiral cooling channel mainly for cooling the stator and with two openings for the in and out of the cooling liquid. By communicating the spiral cooling channel with the first channel 11 and the second channel 12 on the end cover 1, it is achieved that the cooling liquid cools the stator and at the same time the rotor is further cooled by the rotating shaft 3 by letting the cooling liquid into the cooling water pipe 4 placed in the rotating shaft. Further, the shunt 5 is preferably bolted to the end cap 1, or one skilled in the art may also secure the shunt 5 to the end cap 1 by any other and possible means of attachment, such as welding. In addition, the end cap 1 and the flow splitter 5 may be integrally formed as a unitary structure by one skilled in the art. It should be appreciated that in the preferred embodiment of the present invention, the flow splitter 5 is used not only to secure the mounting end 43 of the cooling water tube 4 to the end cap 1, but also to place the first and

second passages

11, 12 on the end cap 1 in communication with the inner and

annular cavities

411, 421, respectively, to allow the flow of cooling water through the inner and

annular cavities

411, 421.

As shown in fig. 1 and 2, the mounting end 43 is provided with a first through hole 431, a second through hole 432, and a mounting hole 433. Wherein, the first through hole 431 is communicated with the inner cavity 411, and the second through hole 432 is communicated with the annular cavity 421. And, when the mounting end 43 is fixed to the flow divider 5 by the bolt passing through the mounting hole 433, the first through hole 431 communicates with the first water port 51, the second through hole 432 communicates with the second water port 52, and further the first passage 11 communicates with the inner cavity 411, and the second passage 12 communicates with the annular cavity 412. So that the cooling fluid (e.g., water) can enter the inner cavity 411 from the first passage 11 through the first water port 51 and the first through hole 431 and then flow through the annular cavity 421 to flow out from the second passage 12 through the second through hole 432 and the second water port 52. Or it is also possible for a person skilled in the art to let the cooling liquid flow from the second channel 12 into the cooling channel and out from the first channel 11.

With further reference to fig. 1 and 2, the motor rotor liquid cooling structure of the present invention further includes a first seal ring 6 disposed within an annular groove 434 on the mounting end 43. In the assembled state, the shunt 5 and the mounting end 43 can press the first seal ring 6, preventing the modified silicone oil in the rotation shaft hole 31 from leaking from the junction of the shunt 5 and the mounting end 43. Further, a second sealing ring 7 is arranged between the shunt 5 and the end cover 1, and is used for preventing the cooling liquid in the first channel 11 and the second channel 12 from entering the motor to damage electric elements in the motor. Further, the lower end of the rotating shaft 3 in fig. 1 is provided with a third seal ring 8 in the radial direction for preventing the modified silicone oil in the rotating shaft hole 31 from entering the inside of the motor, and the seal ring is preferably a rotary seal.

It will be appreciated by those skilled in the art that the sealing effect of the modified silicone oil is effectively achieved by the rotary seal between the diverter 5 and the spindle 3, since the modified silicone oil is better than water in sealing property. Those skilled in the art will also appreciate that since the modified silicone oil has good dielectric strength, the modified silicone oil does not cause damage to the motor even if it enters the inside of the motor. It will be readily understood by those skilled in the art that the connection of the end cap 1 and the cooling water pipe 4 by the flow divider 5 can effectively optimize the processing of the end cap 1 and the sealing performance between the components.

It will also be appreciated by those skilled in the art that in the preferred embodiment of the present invention, the heat generated by the rotor can be rapidly transferred to the cooling water pipe 4 by the modified silicone oil between the inner wall of the rotation shaft hole 13 and the outer wall of the cooling water pipe 4, and then the heat of the cooling water pipe 4 is taken away by the cooling liquid flowing through the inside of the cooling water pipe 4. Therefore, the cooling liquid in the rotor liquid cooling structure can always circulate in the cooling water pipe 4, and cannot enter the motor to cause corrosion and damage to the inside of the motor.

It should be noted that the cooling liquid described above is preferably water, or those skilled in the art may use other cooling liquids, such as hydraulic oil, as needed.

Thus far, the technical solution of the present invention has been described in connection with the preferred embodiments shown in the drawings, but it is easily understood by those skilled in the art that the scope of protection of the present invention is not limited to these specific embodiments. Equivalent modifications and substitutions for related technical features may be made by those skilled in the art without departing from the principles of the present invention, and such modifications and substitutions will fall within the scope of the present invention.

Claims

1. The utility model provides a motor rotor liquid cooling structure, the motor includes casing, end cover, stator, rotor and pivot, be provided with first passageway and second passageway on the end cover, be provided with the pivot hole along the axial in the pivot, its characterized in that, rotor liquid cooling structure includes:

a mounting end fixed to an end of the motor; and

a cooling end which can be accommodated in the rotating shaft hole and is formed with a cooling channel;

wherein the cooling channel communicates with the first channel and the second channel through the mounting end;

the cooling end comprises a first pipeline and a second pipeline sleeved outside the first pipeline, one end of the first pipeline away from the mounting end is communicated with the second pipeline,

the inner cavity of the first pipeline and the annular cavity between the first pipeline and the second pipeline form the cooling channel;

the mounting end and the cooling end are integrally formed.

2. The motor rotor liquid cooling structure of claim 1, wherein the mounting end is provided with a first through hole and a second through hole, the first through hole being capable of communicating the inner cavity with the first channel, the second through hole being capable of communicating the annular cavity with the second channel.

3. The motor rotor liquid cooling structure according to claim 2, wherein a portion of the shaft hole between the second pipe and the shaft hole is filled with a heat conductive medium.

4. A motor rotor liquid cooling structure according to claim 3, wherein ventilation holes are provided in the shaft, and the heat-conducting medium is filled into the shaft holes via the ventilation holes.

5. The motor rotor liquid cooling structure according to claim 4, wherein the heat conducting medium is modified silicone oil.

6. The motor rotor liquid cooling structure according to claim 4, wherein the ventilation holes are provided with ventilation valves.

7. The motor rotor liquid cooling structure of claim 6, wherein the breather valve is a one-way breather valve.

8. The motor rotor liquid cooling structure according to any one of claims 1 to 7, further comprising a flow divider, wherein the mounting end is fixedly connected with an end portion of the motor through the flow divider.