CN113649603B

CN113649603B - Electric spindle

Info

Publication number: CN113649603B
Application number: CN202110995757.9A
Authority: CN
Inventors: 王旭; 李婉; 郭霜; 刘昱; 李瑞炫; 彭石华
Original assignee: Gree Electric Appliances Inc of Zhuhai
Current assignee: Gree Electric Appliances Inc of Zhuhai
Priority date: 2021-08-27
Filing date: 2021-08-27
Publication date: 2022-08-05
Anticipated expiration: 2041-08-27
Also published as: CN113649603A

Abstract

The invention discloses an electric spindle, belonging to the technical field of spindles, the electric spindle comprises: a main shaft; the front bearing is matched with the main shaft; the motor assembly is sleeved outside the main shaft; the first cooling assembly is sleeved outside the main shaft; and the first cooling assembly is positioned between the motor assembly and the front bearing and used for blocking heat generated by the motor assembly from being transferred to the front bearing. According to the invention, the first cooling assembly is arranged between the motor assembly and the front bearing, so that heat at the end part of the motor assembly is consumed by the first cooling assembly before reaching the front bearing, and the influence of heat on the performance of the front bearing due to direct impact on the front bearing is avoided; and because the first cooling assembly is sleeved outside the main shaft, certain consumption can be carried out at the first cooling assembly when heat is transferred to the front bearing through the inside of the main shaft, and the heat transfer is greatly reduced.

Description

Electric spindle

Technical Field

The invention relates to the technical field of spindles, in particular to an electric spindle.

Background

The electric main shaft is a new technology for integrating a machine tool main shaft and a main shaft motor into a whole, and comprises a motor, a main shaft, a bearing and other parts, wherein a rotor of the motor is integrated with the main shaft in a press fit mode, and the main shaft is supported by the front bearing and the rear bearing; because the electric spindle has a compact structure, the electric spindle replaces the traditional spindle with gears, belts or couplings. The thermal elongation of the electric spindle is an important parameter influencing the precision of the electric spindle, and the heat dissipation effect of the electric spindle directly influences the thermal elongation. The motor is a part with the largest heat generated by the electric spindle, and part of the heat generated by the motor is transmitted to the spindle, so that the length of the spindle is changed, and the mutual position relation among parts or parts of the parts is changed, so that the parts are displaced or distorted; another part is transmitted to the front bearing, so that the temperature of the front bearing is increased, and the performance of the front bearing is influenced.

The traditional cooling mode of the electric spindle is as follows: set up cooling channel around the both sides of motor, this kind of cooling mode can reduce the temperature of motor both sides, nevertheless can't cool down to the motor tip, and the heat transfer that the motor tip produced leads to the front bearing because of the high performance degradation of temperature.

Disclosure of Invention

In view of this, the present invention provides an electric spindle, in which a first cooling assembly is disposed between a front bearing and a motor assembly, so as to prevent heat generated by the motor assembly from being directly transferred to the front bearing, and ensure performance of the front bearing.

In order to solve the above-mentioned problems, according to an aspect of the present application, an embodiment of the present invention provides an electric spindle including:

a main shaft;

the front bearing is matched with the main shaft;

the motor assembly is sleeved on the main shaft;

the first cooling assembly is sleeved outside the main shaft; and the first cooling assembly is positioned between the motor assembly and the front bearing and used for blocking heat generated by the motor assembly from being transferred to the front bearing.

Further, the electric spindle further comprises a second cooling assembly, and the second cooling assembly is sleeved on the motor assembly and used for cooling the motor assembly.

Furthermore, the motorized spindle further comprises a water inlet assembly, one part of cooling liquid enters the first cooling assembly after passing through the water inlet assembly, the other part of cooling liquid enters the second cooling assembly, and the cooling liquid entering the first cooling assembly converges into the second cooling assembly.

Further, the first cooling assembly comprises a first cooling ring and a second cooling ring, and the first cooling ring and the second cooling ring form a cooling loop after being matched.

Further, the first cooling ring and the second cooling ring are integrally formed.

Furthermore, one side of the first cooling ring, which is close to the second cooling ring, is provided with at least two circles of first grooves, the adjacent first grooves are communicated end to end, and a liquid inlet is formed in the first groove positioned on the outer ring.

Furthermore, one side of the second cooling ring, which is close to the first cooling ring, is provided with at least two circles of second grooves, the adjacent second grooves are communicated end to end, and the second grooves positioned on the inner ring are provided with liquid outlets.

Furthermore, the first groove and the second groove have the same number of turns and form a cooling loop after matching.

Furthermore, a backflow channel is further formed in the second cooling ring, one end of the backflow channel is communicated with the liquid outlet, and the other end of the backflow channel is communicated with the second cooling assembly.

Furthermore, a first sealing groove is formed in the surface, away from the second cooling ring, of the liquid inlet, and a sealing ring is arranged on the first sealing groove and used for preventing cooling liquid from leaking to the front bearing.

Furthermore, a second sealing groove is formed in the surface, away from the first cooling ring, of the return channel, and a sealing ring is arranged on the second sealing groove and used for preventing cooling liquid from leaking to the motor assembly.

Further, a face of the second cooling ring remote from the first cooling ring is in contact with the electric machine assembly.

Furthermore, the water inlet assembly comprises a flow channel arranged on the electric spindle sleeve, one end of the flow channel is a water inlet end, the other end of the flow channel is a water inlet end, and the water inlet end is communicated with the first cooling assembly and the second cooling assembly.

Furthermore, the second cooling assembly comprises a cooling water jacket, a spiral water channel is formed in the cooling water jacket, an inlet of the spiral water channel is communicated with the water inlet assembly, and the spiral water channel is also communicated with the first cooling assembly through a backflow channel.

Further, the first cooling assembly is interference fit within the cooling water jacket.

Furthermore, the motor assembly comprises a stator and a rotor which are arranged in a matched mode, a clamping groove is formed in the inner circle of the rotor, a retaining shoulder is formed in the main shaft, and the clamping groove and the retaining shoulder are matched to achieve positioning of the rotor in the axial direction.

Furthermore, screens groove all sets up two and both quantity matches with keeping off the shoulder at least.

Further, the rotor and the main shaft are both conical, and the conicity of the joint of the rotor and the main shaft is the same.

Compared with the prior art, the electric spindle has the following beneficial effects:

firstly, the first cooling assembly is arranged between the motor assembly and the front bearing, so that heat at the end part of the motor assembly is consumed by the first cooling assembly before reaching the front bearing, and the influence of the heat on the performance of the front bearing due to the direct impact of the heat on the front bearing is avoided.

Secondly, in the traditional cooling mode of the electric spindle, a cooling channel is arranged around the side surface of the motor, is generally not contacted with the spindle but contacted with a stator of the motor, so that the cooling channel can only realize the cooling of the surface of the stator, and the temperature of the stator close to the spindle is not effectively improved, therefore, the temperature at the position can be transferred to a front bearing through the interior of the spindle; after the scheme is adopted, the first cooling assembly is sleeved on the main shaft, so that certain consumption can be carried out at the first cooling assembly when heat is transferred to the front bearing through the inside of the main shaft, and heat transfer is greatly reduced.

Therefore, the first cooling assembly is positioned between the motor assembly and the front bearing, so that heat is prevented from being transferred from the outside of the main shaft and the end part of the motor assembly to the front bearing; the first cooling assembly is sleeved on the main shaft, so that heat is prevented from being transferred to the front bearing from the interior of the main shaft; the heat consumption is combined inside and outside, the influence of the heat on the front bearing is avoided, the performance of the front bearing is further ensured, and the service life is prolonged.

The foregoing description is only an overview of the technical solutions of the present invention, and in order to make the technical solutions of the present invention more clearly understood and to implement them in accordance with the contents of the description, the following detailed description is given with reference to the preferred embodiments of the present invention and the accompanying drawings.

Drawings

FIG. 1 is a cross-sectional view of an electric spindle provided in accordance with an embodiment of the present invention;

FIG. 2 is a partial enlarged view of the point A in FIG. 1

FIG. 3 is a cross-sectional view of a first cooling ring in an electric spindle, according to an embodiment of the present invention;

FIG. 4 is a front view of a first cooling ring in an electric spindle, according to an embodiment of the present invention;

FIG. 5 is a cross-sectional view of a second cooling ring in an electric spindle, according to an embodiment of the present invention;

FIG. 6 is a front view of a second cooling ring in an electric spindle, according to an embodiment of the present invention;

FIG. 7 is a view of a spindle and stator assembly of an electric spindle according to an embodiment of the present invention;

FIG. 8 is an enlarged view of a portion of FIG. 7 at B;

fig. 9 is an enlarged view of a detent groove in an electric spindle according to an embodiment of the present invention.

Wherein:

100. a main shaft; 200. a front bearing; 300. a motor assembly; 400. a first cooling assembly; 500. a second cooling assembly; 600. a water intake assembly; 101. a shoulder block; 301. a stator; 302. a rotor; 401. a first cooling ring; 402. a second cooling ring; 403. cooling the loop; 501. a cooling water jacket; 502. a spiral water channel; 601. a flow channel; 602. a water inlet end; 603. a water inlet end; 3021. a clamping groove; 4011. a first groove; 4012. a liquid inlet; 4013. a first seal groove; 4021. a second groove; 4022. a liquid outlet; 4023. a return channel; 4024. a second seal groove; 40231. a first return water channel; 40232. a second return water channel; 40233. and a third water return flow channel.

Detailed Description

To further explain the technical means and effects of the present invention adopted to achieve the predetermined object, the following detailed description of the embodiments, structures, features and effects according to the present invention will be made with reference to the accompanying drawings and preferred embodiments. In the following description, different "one embodiment" or "an embodiment" refers to not necessarily the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

In the description of the present invention, it is to be understood that the terms "vertical", "lateral", "longitudinal", "front", "rear", "left", "right", "upper", "lower", "horizontal", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description of the present invention, and do not mean that the device or member to which the present invention is directed must have a specific orientation or position, and thus, cannot be construed as limiting the present invention.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The present embodiment provides an electric spindle, as shown in fig. 1, including:

a main shaft 100, a front bearing 200, a motor assembly 300, and a first cooling assembly 400; wherein the front bearing 200 is engaged with the main shaft 100; the motor assembly 300 is sleeved on the main shaft 100; the first cooling assembly 400 is sleeved outside the main shaft 100; and the first cooling assembly 400 is located between the motor assembly 300 and the front bearing 200 for blocking heat generated from the motor assembly 300 from being transferred to the front bearing 200.

Thus, with the above structure, when the electric spindle works, the motor assembly 300 drives the spindle 100 to rotate, and in this process, the motor assembly 300 generates heat, wherein the heat at the end of the motor assembly 300 is consumed by the first cooling assembly 400, so that the influence of the heat on the front bearing 200 to the performance of the front bearing 200 is avoided; when the heat inside the motor assembly is transferred through the front bearing 200 inside the main shaft 100, a certain consumption is performed at the section of the main shaft 100 included in the first cooling assembly 400, which greatly reduces the heat transfer.

Therefore, the present embodiment blocks heat transfer from the outside of the main shaft 100, the end of the motor assembly 300, to the front bearing 200 by the first cooling assembly 400 being located between the motor assembly 300 and the front bearing 200; the heat is blocked from being transferred from the inside of the main shaft 100 to the front bearing 200 by sleeving the first cooling assembly 400 on the main shaft 100; the combination of the inner and outer portions consumes heat, ensuring that the front bearing 200 is not affected by heat.

It should be noted that: in the electric spindle, the bearings comprise a front bearing and a rear bearing, and in the process of working of the electric spindle, after multiple detections, the temperature rise of the rear bearing is relatively small and is in the temperature rise range, so that only the temperature of the front bearing is generally concerned. However, if the rear bearing also needs to be cooled, a first cooling assembly 400 may be added to the present embodiment and disposed between the motor assembly 300 and the rear bearing to block heat generated by the motor assembly 300 from being transferred to the rear bearing.

In one of the embodiments, to achieve a better cooling effect:

the electric spindle further comprises a second cooling assembly 500, and the second cooling assembly 500 is sleeved on the motor assembly 300 and used for cooling the motor assembly 300.

Specifically, the second cooling assembly 500 is sleeved on the motor assembly 300, so as to effectively cool the outer surface of the motor assembly 300.

So, first cooling module 400 and second cooling module 500 combine, have realized cooling down the tip and the surface of motor element 300 for the cooling is more thorough.

In one embodiment:

the electric spindle further comprises a water inlet assembly 600, after the cooling liquid passes through the water inlet assembly 600, one part of the cooling liquid enters the first cooling assembly 400, the other part of the cooling liquid enters the second cooling assembly 500, and the cooling liquid entering the first cooling assembly 400 blocks heat generated by the motor assembly 300 from being transferred to the front bearing 200 and then flows into the second cooling assembly 500.

Specifically, in this embodiment, the first cooling module 400 and the second cooling module 500 are in a parallel structure by the arrangement of the water inlet module 600, and both share the same water inlet module 600, and the cooling liquid enters the first cooling module 400 to prevent heat generated by the motor module 300 from being transferred to the front bearing 200 and then flows into the second cooling module 500, so that on one hand, heat on the surface of the motor module 300 can be continuously taken away, and on the other hand, the cooling liquid in the second cooling module 500 is discharged after being mixed.

The coolant is not limited to water, and may be cooling oil or the like.

In a specific embodiment:

as shown in fig. 2, the first cooling assembly 400 includes a first cooling ring 401 and a second cooling ring 402, the first cooling ring 401 and the second cooling ring 402 cooperating to form a cooling ring channel 403.

In order to make the first cooling assembly 400 easy to machine, it is configured as a first cooling ring 401 and a second cooling ring 402, and annular grooves with matching shapes and positions are respectively machined on the first cooling ring 401 and the second cooling ring 402, and when the first cooling ring 401 and the second cooling ring 402 are matched, the grooves on the two correspond together to form a cooling loop 403, and cooling liquid flows in the cooling loop 403 to take away heat.

In one embodiment, the first cooling ring 401 and the second cooling ring 402 may be integrally formed by 3D printing or powder metallurgy.

One side of the first cooling ring 401 close to the second cooling ring 402 is provided with at least two circles of first grooves 4011, the adjacent first grooves 4011 are communicated end to end and used for transferring cooling liquid, and a liquid inlet 4012 is formed in the first groove 4011 on the outer ring.

One side of the second cooling ring 402 close to the first cooling ring 401 is provided with at least two circles of second grooves 4021, the adjacent second grooves 4021 are communicated end to end for transmission of cooling liquid, the second grooves 4021 located in the inner circle are provided with liquid outlets 4022, the number of circles of the first grooves 4011 and the number of circles of the second grooves 4021 are the same, and the first grooves 4011 and the second grooves 4021 are matched to form a cooling ring channel 403.

Specifically, as shown in fig. 3 and 4, a face of the first cooling ring 401 close to the second cooling ring 402 is provided with four circles of first grooves 4011, which are, in order from outside to inside: a first ring of first grooves 4011, a second ring of first grooves 4011, a third ring of first grooves 4011 and a fourth ring of first grooves 4011; as shown in fig. 5 and 6, a face of the second cooling ring 402 close to the first cooling ring 401 is provided with four circles of second grooves 4021, which are, in order from outside to inside: a first turn of second grooves 4021, a second turn of second grooves 4021, a third turn of second grooves 4021, and a fourth turn of second grooves 4021.

In the first cooling ring 401, the coolant enters the first ring of first grooves 4011 from a, flows counterclockwise (in the direction of fig. 3) to the tail part of the first ring of first grooves 4011, then enters the head part of the second ring of first grooves 4011, flows clockwise to the tail part of the second ring of first grooves 4011, then enters the head part of the third ring of first grooves 4011, flows counterclockwise to the tail part of the third ring of first grooves 4011, then enters the head part of the fourth ring of first grooves 4011, and flows clockwise to the tail part of the fourth ring of first grooves 4011.

After the second cooling ring 402 is combined, the first ring of first grooves 4011 of the first cooling ring 401 and the first ring of second grooves 4021 of the second cooling ring form a first cooling ring channel, the second ring of first grooves 4011 and the second ring of second grooves 4021 form a second cooling ring channel, the third ring of first grooves 4011 and the third ring of second grooves 4021 form a third cooling ring channel, and the fourth ring of first grooves 4011 and the fourth ring of second grooves 4021 form a fourth cooling ring channel.

During specific work, cooling liquid enters from the liquid inlet 4012, sequentially passes through the first cooling loop, the second cooling loop, the third cooling loop and the fourth cooling loop, and then flows out from the liquid outlet 4022.

More specifically, the second cooling ring 402 is further provided with a backflow channel 4023, one end of the backflow channel 4023 is communicated with the liquid outlet 4022, and the other end of the backflow channel 4023 is communicated with the second cooling assembly 500; thus, after flowing out of the liquid outlet 4022, the cooling liquid enters the second cooling module 500 through the return passage 4023.

In addition, as the liquid outlet 4022 is arranged on the fourth cooling loop and the second cooling module 500 is close to the first cooling loop, the return channel 4023 comprises a first return channel 40231, a second return channel 40232 and a third return channel 40233 which are connected in sequence, the first return channel 40231 is used for vertically leading out the cooling liquid from the fourth cooling loop, then the cooling liquid flows into the vertically arranged third return channel 40233 through the horizontally arranged second return channel 40232, and the third return channel 40233 is communicated with the second cooling module 500; both horizontal and vertical are based on fig. 5.

In one embodiment:

in order to make the first cooling assembly 400 better block heat at the end of the electric machine assembly 300, the second cooling ring 402 of the first cooling assembly 400 is in contact with the electric machine assembly 300 at the side away from the first cooling ring 401; in this way, the heat at the end of the motor assembly 300 is directly absorbed by the first cooling assembly 400, and the heat at the end of the motor assembly 300 is prevented from radiating heat to the rest of the components of the electric spindle.

In one embodiment:

first seal groove 4013 has been seted up to the one side that second cooling ring 402 was kept away from to liquid inlet 4012, and second seal groove 4024 has been seted up to the one side that first cooling ring 401 was kept away from to return channel 4023, all is provided with the sealing washer on first seal groove 4013 and the second seal groove 4024.

Since the side of the liquid inlet 4012 far from the second cooling ring 402 is the front bearing 200, and the side of the return channel 4023 far from the first cooling ring 401 is the motor assembly 300, the present embodiment prevents the coolant from leaking to the front bearing 200 and the motor assembly 300 by the sealing rings.

In one embodiment:

the water inlet assembly 600 comprises a flow channel 601 arranged on the electric spindle sleeve, one end of the flow channel 601 is a water inlet end 602, the other end of the flow channel 601 is a water inlet end 603, and the water inlet end 603 is communicated with both the first cooling assembly 400 and the second cooling assembly 500.

In this embodiment, the water inlet end 602 is used to introduce the cooling fluid into the motorized spindle, and the water inlet end 603 is used to introduce the cooling fluid into the first cooling module 400 and the second cooling module 500.

The second cooling assembly 500 comprises a cooling water jacket 501, a spiral water channel 502 is formed in the cooling water jacket 501, the spiral water channel 502 is communicated with both the water inlet assembly 600 and the first cooling assembly 400, specifically, an inlet of the spiral water channel 502 is communicated with the water inlet assembly 600, and the spiral water channel 502 is also communicated with the first cooling assembly 400 through a backflow channel 4023; thus, after passing through the water inlet assembly 600, a part of the coolant enters the spiral water channel 502, and another part of the coolant enters the first cooling assembly 400, and the coolant entering the first cooling assembly 400 enters the spiral water channel 502 after exchanging heat with heat generated at the end of the motor assembly 300.

In this way, the cooling liquid enters the spiral water channel 502 through the water inlet assembly 600, and the cooling of the motor assembly 300 can be realized.

The first cooling assembly 400 is interference fit within the cooling jacket 501; specifically, the first cooling ring 401 and the second cooling ring 402 are respectively interference-fitted in the cooling water jacket 501, so that the first cooling ring 401 and the second cooling ring 402 are prevented from leaking the cooling liquid due to loose fitting.

In one embodiment:

the motor assembly 300 includes a stator 301 and a rotor 302, which are cooperatively disposed, as shown in fig. 7-9, a locking groove 3021 is formed on an inner circle of the rotor 302, a shoulder 101 is formed on the main shaft 100, and the locking groove 3021 cooperates with the shoulder 101 to achieve positioning of the rotor 302 in an axial direction.

In the traditional electric spindle, a rotor and a spindle are only in conical surface self-locking fit, and the rotor is deformed due to heating in the high-speed operation of the electric spindle, so that the positions of the rotor and the spindle are changed, and the rotor and the spindle are not matched tightly; in the embodiment, the rotor 302 is provided with the locking groove 3021, the main shaft 100 is provided with the shoulder 101, and the locking groove 3021 is matched with the shoulder 101 to realize the tight connection between the rotor 302 and the main shaft 100.

And in one embodiment, rotor 302 and main shaft 100 are both conical and have the same taper at their junction.

Therefore, in the embodiment, the rotor 302 and the main shaft 100 are matched in a manner that the conical surfaces and the tapers are the same, and the retaining shoulder 101 and the retaining groove 3021 are positioned, so that the assembly position is fixed, and the assembly efficiency is effectively improved. The double connection mode effectively prevents the rotor 302 from moving axially in the high-speed rotation process of the electric spindle, and ensures the precision and the service life of the electric spindle.

At least two clamping grooves 3021 and the retaining shoulder 101 are arranged and the number of the clamping grooves and the retaining shoulder is matched; specifically, as shown in fig. 7, three detent grooves 3021 and three retaining shoulders 101 are provided, so that a better positioning effect can be achieved.

The working process of the electric spindle provided by the invention is as follows:

the motor assembly 300 works to drive the main shaft 100 to rotate, and in the process, the motor assembly 300 generates heat, wherein:

the heat generated at the end of the motor assembly 300 is dissipated as follows: the cooling liquid enters the flow channel 601 from the water inlet end 602, then reaches the liquid inlet 4012 through the water inlet end 603, enters from the liquid inlet 4012, passes through the cooling loop 403 formed by matching the first groove 4011 and the second groove 4021, takes away heat generated at the end of the motor assembly 300, and sequentially passes through the first water return flow channel 40231, the second water return flow channel 40232 and the third water return flow channel 40233 to enter the spiral water channel 502;

the heat generated at the surface of the motor assembly 300 is consumed as follows: the cooling liquid enters the flow channel 601 from the water inlet end 602 and then enters the spiral water channel 502 through the water inlet end 603, so that the surface of the motor component 300 is cooled;

in addition, the coolant in the spiral water channel 502 is discharged from the cooling water jacket 501 after passing through the entire spiral water channel.

The electric spindle provided by the invention has the advantages that the first cooling assembly 400 arranged between the motor assembly 300 and the front bearing 200 blocks the heat generated at the end part of the motor assembly 300 from being transferred to the front bearing 200; moreover, since the first cooling module 400 is sleeved on the main shaft 100, when heat is transferred to the front bearing 200 through the inside of the main shaft 100, a certain amount of heat is consumed at the first cooling module 400, which greatly reduces the heat transfer.

The surface of the motor component 300 is cooled through the second cooling component sleeved on the motor component 300; the two cooling assemblies are combined to enable cooling to be more thorough. In addition, the assembly efficiency is effectively improved by adopting conical surfaces at the connection part of the rotor 302 and the main shaft 100, and the conical degrees of the connection part of the rotor 302 and the main shaft 100 are the same, and the mode that the blocking shoulder 101 is matched with the blocking groove 3021 effectively prevents the rotor 302 from axially moving in the high-speed rotation process of the electric main shaft, so that the precision and the service life of the electric main shaft are ensured.

In summary, it is easily understood by those skilled in the art that the advantageous technical features described above can be freely combined and superimposed without conflict.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the present invention in any way, and any simple modification, equivalent change and modification made to the above embodiment according to the technical spirit of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. An electric spindle, characterized in that it comprises:

a main shaft (100);

a front bearing (200), the front bearing (200) cooperating with the main shaft (100);

the motor assembly (300), the said motor assembly (300) is fitted over the basic shaft (100);

the first cooling assembly (400), the first cooling assembly (400) is sleeved outside the main shaft (100); the first cooling assembly (400) is positioned between the motor assembly (300) and the front bearing (200) and used for blocking heat generated by the motor assembly (300) from being transferred to the front bearing (200);

the first cooling assembly (400) comprises a first cooling ring (401) and a second cooling ring (402), wherein annular grooves with matched shapes and positions are machined in the first cooling ring (401) and the second cooling ring (402), and when the first cooling ring (401) and the second cooling ring (402) are matched, the annular grooves in the first cooling ring (401) and the second cooling ring (402) are correspondingly matched to form a cooling ring channel (403).

2. The electric spindle according to claim 1, further comprising a second cooling assembly (500), wherein the second cooling assembly (500) is sleeved on the motor assembly (300) for cooling the motor assembly (300).

3. The electric spindle according to claim 2, characterized in that the electric spindle further comprises a water inlet assembly (600), and after the cooling liquid passes through the water inlet assembly (600), a part of the cooling liquid enters the first cooling assembly (400), another part of the cooling liquid enters the second cooling assembly (500), and the cooling liquid entering the first cooling assembly (400) is merged into the second cooling assembly (500).

4. Electric spindle according to claim 3, characterized in that the first cooling ring (401) and the second cooling ring (402) are integrally formed.

5. The electric spindle according to claim 4, characterized in that one surface of the first cooling ring (401) close to the second cooling ring (402) is provided with at least two circles of first grooves (4011), the adjacent first grooves (4011) are communicated end to end, and a liquid inlet (4012) is arranged on the first groove (4011) on the outer circle.

6. The electric spindle according to claim 5, characterized in that at least two circles of second grooves (4021) are arranged on one surface of the second cooling ring (402) close to the first cooling ring (401), the adjacent second grooves (4021) are communicated end to end, and the second grooves (4021) in the inner circle are provided with liquid outlets (4022).

7. Electric spindle according to claim 6, characterized in that the first recess (4011) and the second recess (4021) have the same number of turns and form a cooling circuit (403) after mating.

8. The electric spindle according to claim 7, characterized in that the second cooling ring (402) further has a backflow channel (4023), and one end of the backflow channel (4023) is communicated with the liquid outlet (4022), and the other end is communicated with the second cooling assembly (500).

9. The electric spindle according to claim 5, characterized in that a first sealing groove (4013) is formed in a surface of the liquid inlet (4012) away from the second cooling ring (402), and a sealing ring is disposed on the first sealing groove (4013) for preventing the cooling liquid from leaking to the front bearing (200).

10. The electric spindle according to claim 8, wherein a second sealing groove (4024) is formed in a surface of the return channel (4023) away from the first cooling ring (401), and a sealing ring is disposed on the second sealing groove (4024) to prevent the cooling liquid from leaking to the motor assembly (300).

11. The electric spindle according to claim 1, characterized in that a face of the second cooling ring (402) remote from the first cooling ring (401) is in contact with the motor assembly (300).

12. The electric spindle of claim 3, wherein the water inlet assembly (600) comprises a flow channel (601) disposed on the electric spindle sleeve, one end of the flow channel (601) is a water inlet end (602), the other end is a water inlet end (603), and the water inlet end (603) is communicated with both the first cooling assembly (400) and the second cooling assembly (500).

13. The electric spindle according to claim 8, characterized in that the second cooling assembly (500) comprises a cooling water jacket (501), a spiral water channel (502) is formed in the cooling water jacket (501), an inlet of the spiral water channel (502) is communicated with the water inlet assembly (600), and the spiral water channel (502) is also communicated with the first cooling assembly (400) through a return channel (4023).

14. The electric spindle according to claim 13, characterized in that the first cooling assembly (400) is interference fitted within a cooling water jacket (501).

15. The electric spindle according to claim 1, wherein the motor assembly (300) comprises a stator (301) and a rotor (302) which are cooperatively arranged, a locking groove (3021) is formed on an inner circle of the rotor (302), a retaining shoulder (101) is formed on the spindle (100), and the locking groove (3021) and the retaining shoulder (101) are cooperatively arranged to realize the positioning of the rotor (302) in the axial direction.

16. Electric spindle according to claim 15, characterized in that the detent groove (3021) and the stop shoulder (101) are provided in at least two and are matched in number.

17. Electric spindle according to claim 15 or 16, characterized in that the rotor (302) and the spindle (100) are both conical and the conicity at the junction is the same.