A heat dissipation device for transmission mechanism of CNC machine tool

Abstract

The present application relates to the technical field of heat dissipation devices. In view of the fact that the screw transmission mechanism of a traditional CNC machine tool is thermally deformed due to overheating during operation, a heat dissipation device for a CNC machine tool transmission mechanism is proposed, comprising a first heat dissipation component, the first heat dissipation component comprising an air cooler and two bellows, the two bellows are respectively located at opposite ends of the screw nut, the bellows are both sleeved on the outer periphery of the screw shaft, and the two ends of the bellows are respectively connected to the screw nut and the bearing seat; the bellows are also connected to a number of air inlet pipes, the air inlet pipes are connected to the air cooler; the outer periphery of the bellows is also provided with a number of air outlets. The present application has the effect of limiting the thermal deformation of the various components of the screw transmission mechanism due to overheating.

Description

Technical Field

[0001] The present application relates to the field of heat dissipation devices, and in particular to a heat dissipation device for a transmission mechanism of a numerically controlled machine tool. Background Art

[0002] As the core component of high-precision processing equipment such as CNC machine tools, the screw drive mechanism is used to complete the feed movement of machine tool tool holders and other components.

[0003] In related technologies, such as Figure 1 and Figure 2 The screw transmission mechanism 1 on the machine tool includes a ball screw pair, a mounting groove 10, a slide 14 and a rotary drive member; the mounting groove 10 is formed on the machine tool bed, the ball screw pair includes a screw shaft 11 and a screw nut 12, both ends of the screw shaft 11 are rotatably mounted in the mounting groove 10 through a bearing seat 13, the bottom of the slide 14 is connected to the screw nut 12 through a connecting seat 141, and the opposite sides of the bottom of the slide 14 are slidably installed on both sides of the mounting groove 10 through a slider rail structure; the flange of the drive motor 15 is fixed to the bearing seat 13 by bolts, and the output shaft of the drive motor 15 is coaxially connected to the screw shaft 11 on the bearing seat 13.

[0004] After the tool holder and other components of the CNC machine tool are installed on the slide, the lead screw shaft is driven to rotate by the driving motor. During the rotation of the lead screw shaft, the lead screw nut and the slide are driven to reciprocate along the axial direction of the lead screw shaft to realize the feeding of the tool holder.

[0005] With regard to the above-mentioned related technologies, during the operation of the screw transmission mechanism, when the screw nut reciprocates on the screw shaft, the friction between the two will generate a large amount of heat, which can easily cause the temperature of the screw shaft and the screw nut to rise, resulting in thermal deformation of the screw shaft and the screw nut, thereby affecting the transmission accuracy of the screw transmission mechanism. Therefore, there is room for improvement. Summary of the invention

[0006] In order to reduce the thermal deformation of the components of the screw transmission mechanism of a CNC machine tool due to overheating during operation, thereby affecting the transmission accuracy of the screw transmission mechanism, the present application provides a heat dissipation device for the transmission mechanism of a CNC machine tool.

[0007] The present application provides a heat dissipation device for a CNC machine tool transmission mechanism, which adopts the following technical solution:

[0008] A heat dissipation device for a transmission mechanism of a numerically controlled machine tool comprises a first heat dissipation component, wherein the first heat dissipation component comprises an air cooler and two bellows, wherein the two bellows are respectively located at opposite ends of a screw nut, the bellows are both sleeved on the outer periphery of the screw shaft, and the two ends of the bellows are respectively connected to the screw nut and a bearing seat; the bellows are also connected to a plurality of air inlet pipes, and the air inlet pipes are connected to the air cooler; and a plurality of air outlets are also opened on the outer periphery of the bellows.

[0009] By adopting the above technical solution, when the subsequent driving motor drives the screw shaft to rotate to drive the screw nut to reciprocate along the screw shaft, the cold air is continuously input into the bellows through the air inlet pipe by the air cooler. The cold air input into the bellows is output from the air outlet after heat exchange with the screw shaft, so as to realize the cooling of the screw shaft in the bellows and reduce the thermal deformation of the screw shaft due to excessive heating, which affects the transmission accuracy of the screw transmission mechanism. The setting of the bellows, the two bellows can be extended and retracted with the movement of the screw nut and remain sleeved on the outer periphery of the screw shaft. On the one hand, the cold air output from the air inlet pipe can act more concentratedly on the screw shaft; on the other hand, the bellows can limit the chips generated when the CNC machine tool processes the workpiece to contaminate the screw shaft, which is conducive to maintaining the normal rotation of the screw shaft.

[0010] Preferably, the air outlets on the outer periphery of the corrugated pipe are all arranged toward the mounting groove.

[0011] By adopting the above technical solution, the cold air entering the bellows is output through the air outlet after heat exchange with the screw shaft and acts on the installation groove. The cold air output from the air outlet can blow off the chips remaining on the installation groove, making it easier to clean the chips on the installation groove.

[0012] Preferably, both ends of the bellows are coaxially connected with connecting pipes, and one end of the connecting pipe away from the bellows is coaxially connected with a main connecting flange, and the main connecting flanges at both ends of the bellows are respectively connected to the bearing seat and the screw nut by bolts.

[0013] By adopting the above technical solution, on the one hand, the bellows can be firmly sleeved on the outer periphery of the screw shaft; on the other hand, the two ends of the bellows can be detachably installed on the screw nut and the bearing seat respectively, which facilitates the disassembly, assembly and replacement of the bellows.

[0014] Preferably, it also includes a second heat dissipation component, which includes a semiconductor refrigeration plate, the cooling surface of the semiconductor refrigeration plate is bonded to the connecting seat at the bottom of the slide, and the heat conduction surface of the semiconductor refrigeration plate is supported by a heat dissipation fan.

[0015] By adopting the above technical solution, the cold energy generated by the semiconductor cooling sheet is transferred to the connecting seat and the screw nut through the cooling surface of the semiconductor cooling sheet, thereby reducing the temperature of the screw nut, reducing the thermal deformation of the screw nut due to the temperature increase, and reducing the transmission accuracy of the screw transmission structure. The setting of the heat dissipation fan is convenient for better dissipation of the heat of the semiconductor cooling sheet.

[0016] Preferably, the heat conducting surface of the semiconductor cooling sheet is bonded and connected to a fin heat sink, and the cooling fan is installed on a side of the fin heat sink facing away from the semiconductor cooling sheet.

[0017] By adopting the above technical solution and setting the fin heat sink, it is beneficial to increase the heat dissipation area of ​​the heat conducting surface of the semiconductor refrigeration plate, improve the heat dissipation efficiency of the heat conducting surface, and facilitate better heat dissipation of the heat conducting surface of the semiconductor refrigeration plate.

[0018] Preferably, the second heat dissipation component also includes a heat dissipation pipe, one end of the heat dissipation pipe is installed on the connecting seat, and the semiconductor refrigeration plate is installed on the end of the heat dissipation pipe close to the connecting seat; the end of the heat dissipation pipe away from the connecting seat is bent and arranged toward the installation groove.

[0019] By adopting the above technical solution, the airflow generated by the rotation of the cooling fan is concentrated and directed to the mounting groove on the machine tool bed through the heat dissipation pipe to flush and clean the chips remaining on the mounting groove when the machine tool processes the workpiece, thereby facilitating the cleaning of the chips on the mounting groove.

[0020] Preferably, the cooling surface of the semiconductor refrigeration plate is bonded to the connecting seat via thermal conductive silicone grease, and the thermal conductive surface of the semiconductor refrigeration plate is bonded to the fin heat sink via thermal conductive silicone grease.

[0021] By adopting the above technical scheme, it is beneficial to improve the heat transfer efficiency between the cooling surface and the connecting seat and between the heat conducting surface and the fin heat sink, so that the cold energy generated by the cooling surface of the semiconductor refrigeration plate can be better transferred to the connecting seat and act on the screw nut through the connecting seat, so that the heat conducting surface of the semiconductor refrigeration plate can better transfer the heat to the fin heat sink for heat dissipation.

[0022] Preferably, a third heat dissipation component is further included, and the third heat dissipation component includes a heat insulation plate and a cooling water circulation machine. The heat insulation plate is located between the driving motor and the bearing seat. A flow channel groove is arranged in the heat insulation plate. The two ends of the flow channel groove are respectively connected to a water inlet pipe and a water outlet pipe. The water inlet pipe and the water outlet pipe are respectively connected to the water supply end and the return end of the cooling water circulation machine.

[0023] By adopting the above technical solution, the heat generated by the drive motor during operation can be easily transferred to the screw shaft through the bearing seat, causing the screw shaft to heat up. Through the arrangement of the heat insulation board and the cooling water circulation machine, during the operation of the drive motor, cooling water is circulated into the flow channel groove of the heat insulation board through the cooling water circulation machine to absorb the heat generated by the drive motor during operation, thereby cooling the drive motor and limiting the heat of the drive motor from being directly transferred to the bearing seat and the screw shaft on the bearing seat, thereby reducing the temperature increase of the screw shaft due to the heat transfer from the drive motor.

[0024] In summary, the present application includes at least one of the following beneficial technical effects:

[0025] 1. Through the setting of the screw shaft cooling component, during the operation of the screw transmission mechanism, the air cooler continuously introduces cold air into the telescopic tube through the air inlet pipe. The cold air enters the telescopic tube and exchanges heat with the screw shaft before being discharged through the air outlet on the telescopic tube, thereby cooling and dissipating the heat of the screw shaft and reducing the thermal deformation of the screw shaft due to excessive temperature, which leads to reduced accuracy of the screw transmission mechanism. At the same time, a telescopic tube is sleeved on the outer periphery of the screw shaft and the two ends of the telescopic tube are respectively connected to the opposite end of the screw nut and the bearing seat. When the screw nut moves axially on the screw shaft, the telescopic sleeve can be extended and retracted accordingly. On the one hand, it is convenient to shield the screw shaft to limit the chips generated during CNC machine tool processing from contacting the screw shaft; on the other hand, the telescopic sleeve can gather the cold air output from the air inlet pipe, so that the cold air output from the air inlet pipe can act more concentratedly on the screw shaft.

[0026] 2. Through the provision of the second heat dissipation component, during the operation of the screw transmission mechanism, the cold air is transferred toward the connecting seat through the cooling surface of the semiconductor refrigeration plate to cool the connecting seat and the screw nut.

[0027] 3. One end of the connecting pipe is connected to the side of the connecting seat, and the end of the connecting pipe away from the connecting seat is bent and bent toward the installation groove. The connecting pipe is then used to concentrate the airflow generated when the cooling fan rotates and guide it into the installation groove, so as to flush the residual chips in the installation groove and reduce the accumulation of chips generated during CNC machine tool processing in the installation groove. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram used in this application to illustrate the existing machine tool screw transmission mechanism.

[0029] Figure 2 This application is a schematic diagram used to illustrate the connection relationship between the existing slide and the screw nut.

[0030] Figure 3 This is a schematic diagram used in this application to illustrate the screw transmission mechanism and the heat dissipation device.

[0031] Figure 4 It is a schematic diagram used in this application to illustrate the first heat dissipation component.

[0032] Figure 5 yes Figure 4 Enlarged schematic diagram of part A in the middle.

[0033] Figure 6 It is a schematic diagram used in this application to illustrate the second heat dissipation component.

[0034] Figure 7 yes Figure 6 Enlarged schematic diagram of part A in the middle.

[0035] Figure 8This is an exploded schematic diagram used in this application to illustrate the bearing seat, heat insulation plate and drive motor.

[0036] Description of reference numerals:

[0037] 1. Screw transmission mechanism; 10. Mounting groove; 11. Screw shaft; 12. Screw nut; 13. Bearing seat; 14. Slide; 141. Connecting seat; 15. Driving motor; 2. Bellows; 21. Air inlet pipe; 22. Connecting pipe; 23. Main connecting flange; 20. Air outlet; 3. Secondary heat dissipation component; 30. Heat dissipation pipe; 301. Air inlet hole; 302. Secondary connecting flange; 303. Annular mounting plate; 31. Semiconductor cooling sheet; 32. Finned heat sink; 33. Cooling fan; 4. Heat insulation board; 40. Perforation; 41. Water inlet pipe; 42. Water outlet pipe. DETAILED DESCRIPTION

[0038] The following is combined with Figure 1-8 This application is described in further detail.

[0039] Reference Figure 1 and Figure 2 The existing machine tool screw transmission mechanism 1 includes a mounting groove 10, a ball screw pair, a slide 14, the mounting groove 10 and a driving motor 15, the ball screw pair includes a screw shaft 11 and a screw nut 12; wherein the mounting groove 10 is formed on the machine tool bed, and both ends of the screw shaft 11 are rotatably supported on the mounting shaft through a bearing seat 13; the screw nut 12 is threadedly connected to the screw shaft 11; the opposite sides of the bottom of the slide 14 are slidably connected to the machine tool bed through a slider slide rail structure, and a connecting seat 141 is provided at the bottom of the slide 14 corresponding to the screw nut 12, and a connecting groove for the screw nut 12 to be embedded is provided at the bottom of the connecting seat 141, and the screw nut 12 is embedded in the connecting seat 141 through the connecting groove, and the driving motor 15 is flange-fixed on the bearing seat 13 at one end of the screw shaft 11, and one end of the output shaft of the driving motor 15 is coaxially connected to the screw shaft 11 through a coupling.

[0040] The present application embodiment discloses a heat dissipation device for a transmission mechanism of a numerically controlled machine tool, referring to Figure 3 and Figure 4 , including a first heat dissipation component, a second heat dissipation component 3 and a third heat dissipation component. The first heat dissipation component is installed on the screw shaft 11, and is used to dissipate heat and cool the screw shaft 11. The screw shaft 11 is installed on the connecting seat 141, and is used to dissipate heat and cool the connecting seat 141 and the screw nut 12. The third heat dissipation component is installed between the drive motor 15 and the screw shaft 11, and is used to dissipate heat and cool the drive motor 15.

[0041] The first heat dissipation component includes an air cooler and two bellows 2; the two bellows 2 are respectively located at the two ends of the screw nut 12, the bellows 2 are coaxially sleeved on the outer periphery of the screw shaft 11 between the screw nut 12 and the bearing seat 13, and the two ends of the bellows 2 are respectively connected to the screw nut 12 and the bearing seat 13, and the outer periphery of the bellows 2 is connected to a plurality of air inlet pipes 21; the air inlet pipes 21 are all connected to the air cooler; the outer periphery of the bellows 2 is also provided with an air outlet 20.

[0042] Subsequently, the driving motor 15 drives the screw shaft 11 to rotate, thereby driving the screw nut 12 and the slide 14 to move along the screw shaft 11. The cold air fan is used to continuously inject cold air into the bellows 2 through the air inlet pipe 21. The cold air entering the bellows 2 exchanges heat with the screw shaft 11 to achieve heat dissipation and cooling of the screw shaft 11, and then flows out from the air outlet 20.

[0043] By setting the bellows 2, on the one hand, when the slide 14 and the screw nut 12 reciprocate along the screw shaft 11, the two bellows 2 can be extended and retracted accordingly and always remain sleeved on the outer periphery of the screw shaft 11, limiting the impact of the first heat dissipation component on the normal operation of the screw transmission mechanism 1, and at the same time limiting the situation where the chips generated during CNC machine tool processing contaminate the screw shaft 11. On the other hand, the bellows 2 can gather the cold air output by the air inlet pipe 21, so that the cold air output by the air inlet pipe 21 can act more concentratedly on the screw shaft 11, which is conducive to improving the cooling and heat dissipation efficiency of the screw shaft 11.

[0044] Reference Figure 4 and Figure 5 The air outlet 20 on the periphery of the bellows 2 is in the shape of a long strip, and the length direction of the air outlet 20 is arranged parallel to the axial direction of the bellows 2; the air outlets 20 are all facing the mounting groove 10 of the machine tool bed. On the one hand, the cold air blown out through the air outlet 20 on the periphery of the bellows 2 can directly act on the mounting groove 10, so as to flush and clean the chips in the mounting groove 10 and reduce the accumulation of chips in the mounting groove 10. On the other hand, it limits the chips dropped during the subsequent machine tool processing from entering the bellows 2 through the air outlet 20, resulting in the contamination of the screw shaft 11.

[0045] Both ends of the bellows 2 are coaxially connected with connecting pipes 22, and the end of the connecting pipe 22 away from the bellows 2 is coaxially connected with a main connecting flange 23. The main connecting flanges 23 at both ends of the bellows 2 are respectively connected to the proximal ends of the screw nut 12 and the bearing seat 13 by bolts, so that the bellows 2 can be detachably installed on the screw shaft 11, which is convenient for the disassembly, assembly and replacement of the bellows 2.

[0046] Reference Figure 6 and Figure 7The second heat dissipation component 3 includes a heat dissipation pipe 30, and a semiconductor refrigeration plate 31 is arranged at one end of the heat dissipation pipe 30 close to the connecting seat 141. The cooling surface of the semiconductor refrigeration plate 31 is arranged toward the connecting seat 141 and the cooling surface is attached to the outer side of the connecting seat 141 through thermal conductive silicone grease. Through the above arrangement, the cold energy generated by the thermal conductive surface of the semiconductor refrigeration plate 31 can be subsequently applied to the connecting seat 141 and the lead screw nut 12 to achieve heat dissipation and cooling of the lead screw nut 12, thereby reducing thermal deformation of the lead screw nut 12 due to excessive temperature.

[0047] The heat conducting surface of the semiconductor cooling sheet 31 is also provided with a fin heat sink 32. The heat conducting surface of the semiconductor cooling sheet 31 is attached to the fin heat sink 32 through thermal grease. The provision of the fin heat sink 32 is conducive to increasing the heat dissipation area of ​​the heat conducting surface, and facilitates better heat dissipation of the heat conducting surface of the semiconductor cooling sheet 31.

[0048] The outer periphery of one end of the heat dissipation pipe 30 is coaxially connected with a secondary connection flange 302, which is fixed to the outer side of the connection seat 141 by bolts, so that the heat dissipation pipe 30 is firmly connected to the connection seat 141. An annular mounting plate 303 is provided at one end of the heat dissipation pipe 30 close to the connection seat 141; the outer periphery of the semiconductor cooling sheet 31 and the outer periphery of the finned heat sink 32 are both glued to the inner periphery of the annular mounting plate 303; the outer periphery of the annular mounting plate 303 is fixed to the inner periphery of the heat dissipation pipe 30 by glue, so that the semiconductor cooling sheet 31 and the finned heat sink 32 are firmly installed in the connection pipe 22, and at the same time, the cooling surface of the semiconductor cooling sheet 31 is more closely attached to the side of the connection seat 141.

[0049] A cooling fan 33 is also installed on the side of the fin heat sink 32 facing away from the semiconductor cooling fin 31, and the cooling fan 33 is fixed to the fin heat sink 32 by bolts. A plurality of air inlet holes 301 are circumferentially opened on the tube wall of the heat pipe 30 opposite to the fin heat sink 32. Through the above arrangement, the cooling fan 33 is used to accelerate the air flow in the connecting tube 22, and the airflow generated by the cooling fan 33 is used to accelerate the heat dissipation of the heat conduction surface of the semiconductor cooling fin 31 through the fin heat sink 32 and out of the heat pipe 30, which is beneficial to improve the heat dissipation efficiency of the heat conduction surface of the semiconductor cooling fin 31.

[0050] A section of the heat dissipation pipe 30 away from the connection seat 141 is bent and arranged toward the mounting groove 10, so that the airflow blown out by the heat dissipation fan 33 can directly act on the mounting groove 10, and the mounting groove 10 is flushed by the airflow to reduce the accumulation of chips generated during CNC machine tool processing in the mounting groove 10, which makes subsequent cleaning difficult.

[0051] Reference Figure 3 and Figure 8The third heat dissipation component includes a heat insulation board 4 and a cooling water circulation machine; the heat insulation board 4 is located between the drive motor 15 and the bearing seat 13, and the opposite sides of the heat insulation board 4 are respectively attached to the bearing seat 13 and the drive motor 15 flange, and the heat insulation board 4 is provided with a through hole 40 for the output end of the drive motor 15 to pass through, and the output end of the drive motor 15 is passed through the heat insulation board 4 through the through hole 40. A flow channel groove is provided in the heat insulation board 4, and the flow channel groove is distributed in a serpentine shape; the two ends of the flow channel groove are respectively connected with an inlet pipe 41 and an outlet pipe 42, and the inlet pipe 41 and the outlet pipe 42 are respectively connected with the water supply end and the return end of the cooling water circulator. Through the above arrangement, during the subsequent operation of the screw transmission mechanism 1, cooling water is circulated and pumped into the flow channel groove in the heat insulation board 4 through the cooling water circulator, and the cooling water pumped into the flow channel groove is used to absorb the heat generated during the operation of the drive motor 15, so as to cool down and dissipate the heat of the drive motor 15, and at the same time, limit the heat of the drive motor 15 from being transferred to the bearing seat 13 and the screw shaft 11.

[0052] The flange of the driving motor 15 and the heat insulation board 4 are fixed to the bearing seat 13 by a plurality of bolts, so that the heat insulation board 4 is stably installed between the bearing seat 13 and the driving motor 15 .

[0053] The implementation principle of the embodiment of the present application is that the driving motor 15 drives the screw shaft 11 to rotate, so as to drive the screw nut 12 and the slide 14 to reciprocate along the axial direction of the screw shaft 11, and the cold air fan is used to continuously input cold air into the bellows 2 through the air inlet pipe 21 on the bellows 2 to cool and dissipate the heat of the screw shaft 11 ribs on the inner periphery of the bellows 2; the cold amount is transferred to the connecting seat 141 through the cooling surface of the semiconductor refrigeration plate 31 to cool and dissipate the heat of the screw nut 12 in the connecting seat 141, and cooling water is continuously input into the flow channel groove in the insulation board 4 through the cooling water circulator to dissipate heat and cool the driving motor 15; and the components of the screw transmission mechanism 1 are reduced from thermal deformation due to excessive temperature during operation, thereby affecting the transmission accuracy of the screw transmission mechanism 1.

[0054] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A heat dissipation device for a transmission mechanism of a numerically controlled machine tool, characterized in that: The invention comprises a first heat dissipation component, wherein the first heat dissipation component comprises an air cooler and two bellows (2), wherein the two bellows (2) are respectively located at opposite ends of a screw nut (12), the bellows (2) are both sleeved on the outer circumference of a screw shaft (11), and the two ends of the bellows (2) are respectively connected to the screw nut (12) and a bearing seat (13); the bellows (2) is also connected to a plurality of air inlet pipes (21), and the air inlet pipes (21) are connected to the air cooler; the outer circumference of the bellows (2) is also provided with a plurality of air outlets (20); the air outlets (20) are in the shape of long strips; The air outlets (20) on the outer periphery of the corrugated pipe (2) are all arranged toward the mounting groove (10); It also includes a second heat dissipation component (3), the second heat dissipation component (3) includes a semiconductor cooling plate (31), the cooling surface of the semiconductor cooling plate (31) is attached to the connection seat (141) at the bottom of the slide (14), and the heat conduction surface of the semiconductor cooling plate (31) is supported by a heat dissipation fan (33); The heat-conducting surface of the semiconductor cooling sheet (31) is bonded to a finned heat sink (32), and the cooling fan (33) is installed on a side of the finned heat sink (32) facing away from the semiconductor cooling sheet (31); The second heat dissipation component (3) further comprises a heat dissipation tube (30), one end of the heat dissipation tube (30) being mounted on a connection seat (141), and the semiconductor cooling plate (31) being mounted on an end of the heat dissipation tube (30) close to the connection seat (141); an end of the heat dissipation tube (30) away from the connection seat (141) is bent and arranged toward the mounting groove (10).

2. A heat dissipation device for a transmission mechanism of a numerically controlled machine tool according to any one of claim 1, characterized in that: Both ends of the bellows (2) are coaxially connected to connecting pipes (22), and one end of the connecting pipe (22) away from the bellows (2) is coaxially connected to a main connecting flange (23). The main connecting flanges (23) at both ends of the bellows (2) are respectively connected to the bearing seat (13) and the screw nut (12) by bolts.

3. The heat dissipation device for a transmission mechanism of a numerically controlled machine tool according to claim 2, characterized in that: The cooling surface of the semiconductor cooling sheet (31) is bonded to the connection seat (141) via thermally conductive silicone grease, and the thermally conductive surface of the semiconductor cooling sheet (31) is bonded to the fin heat sink (32) via thermally conductive silicone grease.

4. The heat dissipation device for a transmission mechanism of a numerically controlled machine tool according to claim 1, characterized in that: The invention also includes a third heat dissipation component, which includes a heat insulation plate (4) and a cooling water circulation machine. The heat insulation plate (4) is located between the drive motor (15) and the bearing seat (13). A flow channel groove is arranged in the heat insulation plate (4). The two ends of the flow channel groove are respectively connected to a water inlet pipe (41) and a water outlet pipe (42). The water inlet pipe (41) and the water outlet pipe (42) are respectively connected to the water supply end and the water return end of the cooling water circulation machine.

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