Vertical engraving and milling machine

Abstract

The present invention provides a vertical engraving and milling machine, which belongs to the technical field of mechanical processing equipment. It solves the problem of poor waterproof performance of the motor of the existing vertical engraving and milling machine. The vertical engraving and milling machine includes a frame and at least one group of processing components arranged on the frame, the processing components include a motor, a waterproof cover is fixed to the front end of the motor, the inner side of the waterproof cover has a waterproof cavity, the front end of the motor or the waterproof cover is provided with an air intake structure for air intake of the waterproof cavity, the output end of the motor shaft for installing the tool passes through the waterproof cavity and extends out of the waterproof cover, an impeller is fixed on the motor shaft, the impeller is located in the waterproof cavity, and the side of the impeller that discharges air faces the direction in which the output end of the motor shaft extends. The motor of the vertical engraving and milling machine has high waterproof performance.

Description

Technical Field

[0001] The invention belongs to the technical field of mechanical processing equipment and relates to a vertical engraving and milling machine. Background Art

[0002] A milling machine is a processing equipment that can perform engraving and milling on workpieces. The engraving and milling machine is equipped with a motor that can move in multiple dimensions. A tool is installed on the output shaft of the motor to perform three-dimensional processing on the workpiece. Due to the high speed of the motor, the motor needs to be cooled. Unlike the common air-cooled motor that is cooled by a fan, a large amount of dust will be generated during the engraving and milling process. The air-cooled motor will suck the dust into the motor and affect the motor performance. The engraving and milling machine usually uses water cooling to cool the motor, that is, when the motor is in a horizontal state, its lower part can be immersed in water for cooling, but the motor shaft of the motor extends out of the motor housing, and the motor shaft and the motor housing are a rotating matching structure. Therefore, the matching position of the motor and the motor housing needs to be sealed to prevent water from entering.

[0003] At present, the most common sealing method to prevent water ingress is to set a dynamic seal between the motor shaft and the motor housing, such as the sealing structure of the submersible motor disclosed in the patent document (application number: 201720734726.7), which includes a sealing assembly. The sealing assembly includes a sealing static ring, a sealing dynamic ring and a spring. A sealing groove is provided on the inner end face of the housing, and the sealing static ring is positioned in the sealing groove. The sealing dynamic ring and the sealing static ring form a seal. In addition, in order to increase the sealing performance, multiple groups of sealing assemblies are arranged along the axial direction of the motor shaft. This conventional sealing structure is suitable for most motors that do not require high speeds, usually for motors with a speed of several thousand revolutions per minute. However, the motors on engraving and milling machines have high speed requirements when engraving and milling. They are high-speed motors with a speed of tens of thousands of revolutions per minute. At this high speed, the dynamic seal, a contact seal, will wear quickly, resulting in a rapid decrease in sealing performance, affecting the sealing performance.

[0004] Since the above-mentioned decline in sealing performance is caused by the wear of the dynamic seal, it is easy for technical personnel in this field to think of adopting a sealing method that is not easy to wear, such as the motor dynamic sealing device disclosed in the patent document (application number: 201811569347.2), which sets a cavity in the motor, and uses the test equipment to evacuate the motor cavity and inject insulating hydraulic oil, and the insulating hydraulic oil is used to ensure the rotating sealing performance of the motor. However, since the insulating hydraulic oil itself needs to be sealed, and when it is suitable for high-speed motors, the insulating hydraulic oil will heat up and atomize under high-speed rotation, thereby affecting the sealing performance.

[0005] In view of the fact that the decline in sealing performance is due to the wear or atomization caused by the contact between the sealing component and the highly rotating motor shaft, it is easy for those skilled in the art to think of adopting a sealing method that does not contact the motor shaft, such as the motor waterproof mechanism disclosed in the patent document (application number: 201821491784.2), which includes a compressed air pipe, a first guide groove and a second guide groove surrounding the motor shaft are provided at the shaft outlet end of the grinding wheel motor, the second guide groove is connected to the first guide groove, and the compressed air pipe is installed at the inlet end of the first guide groove through a pipe joint; the inlet end of the compressed air pipe is connected to the air compressor, and the waterproof The mechanism causes compressed air to be ejected at high speed to the outside of the motor through the guide groove, blocking cooling water from entering the inside of the motor, thereby fully protecting the grinding wheel motor. However, the motor of this engraving and milling machine needs to move and rotate in multiple dimensions, and the motor is connected to the compressor through an air pipe. During the movement and rotation of the motor, the air pipe will cause it to be entangled with the motor or the workpiece, making it difficult to apply to the engraving and milling machine. At the same time, an independent compressor needs to be set up as a power source for inflation, which increases the cost. When the compressor and the motor are not working synchronously, for example, when the motor is working but the compressor is not working, water will enter the motor. The reliability is low and there is a great risk. Summary of the invention

[0006] The purpose of the present invention is to solve the problem of poor waterproof performance of the motor of the existing vertical engraving and milling machine in view of the above problems in the existing technology, and to propose a vertical engraving and milling machine.

[0007] The object of the present invention can be achieved through the following technical solutions: a vertical engraving and milling machine, comprising a frame and at least one group of processing components arranged on the frame, the processing components comprising a motor, characterized in that a waterproof cover is fixed to the front end of the motor, the inner side of the waterproof cover has a waterproof cavity, an air intake structure for air intake into the waterproof cavity is provided on the front end of the motor or the waterproof cover, the output end of the motor shaft for installing a tool passes through the waterproof cavity and extends out of the waterproof cover, an impeller is fixed on the motor shaft, the impeller is located in the waterproof cavity, and the side of the impeller that outlets air faces the direction in which the output end of the motor shaft extends.

[0008] A waterproof cover extends out of the output end of the motor shaft for installing a tool. The waterproof cover is fixed at the front end of the motor. The two can be sealed by conventional seals such as sealing pads and sealing rings. The motor shaft extends out from the front end of the waterproof cover. The motor shaft and the waterproof cover are in a rotational fit relationship. When the motor is in a horizontal state and the lower part is immersed in water for cooling and the workpiece is processed at the same time, the motor shaft rotates at a high speed, driving the impeller to rotate at a high speed. The impeller can generate a forward airflow, and the airflow enters the waterproof cavity from the air intake structure. The side of the impeller that discharges air faces the direction in which the output end of the motor shaft extends, that is, the side of the impeller that discharges air faces the matching position of the motor shaft and the waterproof cover. Therefore, the airflow generated by the impeller can impact the matching position of the motor shaft and the waterproof cover from the inside to the outside, thereby A certain air pressure is generated between the front side of the impeller and the inner side of the waterproof cover to prevent external water from penetrating from the matching position of the motor shaft and the waterproof cover, thereby improving the waterproof performance. Compared with the existing method of sealing the matching position of the motor shaft and the waterproof cover by mechanical seal, this motor seals and waterproofs through the airflow generated by the impeller. There is no need to install traditional easily worn sealing components such as mechanical seals and sealing rings at the matching position of the motor shaft and the waterproof cover, thereby improving stability. At the same time, since the impeller is directly installed on the motor shaft, the power of the motor itself is directly utilized, thereby simplifying the structure and making the impeller rotation always synchronized with the motor operation, that is, the impeller can definitely play a waterproof role when the motor is working, thereby ensuring the stability and reliability of the motor operation.

[0009] In the vertical engraving and milling machine described above, the waterproof cover is cylindrical, and has a center hole on the outer end surface of the waterproof cover. The output end of the motor shaft extends from the center hole, and the side of the impeller that discharges air is opposite to the center hole. The motor shaft is also fixed with an outer rotating cover that can block the center hole. The motor shaft extends from the center hole. In order to avoid interference with the rotation of the motor shaft, there is a certain gap between the motor shaft and the center hole. For this purpose, an outer rotating cover is provided for blocking. The outer rotating cover is fixed on the motor shaft and can rotate at high speed with the motor shaft. Therefore, the outer rotating cover can cause the water at the outer end of the center hole to generate a vortex and diffuse radially outward, reducing the water pressure at the outer end of the center hole, thereby assisting the external airflow generated by the impeller to improve the waterproof performance.

[0010] In the above-mentioned vertical milling machine, the outer rotating cover end surface has an annular sealing convex edge on the circumference, the sealing convex edge is embedded in the center hole of the waterproof cover, and there is a gap between the outer peripheral surface of the sealing convex edge and the wall of the center hole, and the side of the impeller that discharges air faces the gap between the outer peripheral surface of the sealing convex edge and the wall of the center hole. The sealing convex edge is embedded in the center hole, and there is a gap between the two. The existence of the gap can make the airflow generated by the impeller rush out, avoid excessive air pressure in the waterproof cavity causing excessive resistance to the impeller rotation, reduce motor load and energy consumption, and at the same time, the sealing convex edge rotates at a high speed. Even if part of the water flow enters the gap between the sealing convex edge and the center hole, it is difficult to further enter the waterproof cavity under the action of centrifugal force, thereby ensuring waterproof performance.

[0011] In the vertical milling machine, the outer peripheral surface of the output end of the motor shaft has an external thread, and the impeller is sleeved on the motor shaft and fixed by threaded fit. The impeller is fixed on the motor shaft by threaded fit, so the axial position of the impeller relative to the motor shaft can be adjusted, that is, the distance between the impeller and the inner end surface of the waterproof cover can be adjusted according to the external water pressure, thereby adjusting the impact force of the airflow generated by the impeller on the center hole to ensure waterproof performance.

[0012] In the vertical milling machine described above, an inner cover is also sleeved on the motor shaft, and the inner cover and the outer cover are both fixed on the motor shaft by threaded fit, and the impeller is located between the inner cover and the outer cover, and the sealing convex edges of the inner cover and the outer end cover respectively abut against the two ends of the impeller. The inner cover, the impeller and the outer cover are all fixed by threaded fit, and the three abut against each other, thereby achieving interlocking, preventing the impeller from rotating relative to the motor shaft and axial displacement, and ensuring the stability of the impeller.

[0013] In the vertical milling machine, the outer end surface of the waterproof cover has a groove, the center hole is located on the bottom surface of the groove, and the bottom surface of the groove also has an annular waterproof convex edge in the circumferential direction. The end surface of the outer rotating cover also has an annular waterproof groove in the circumferential direction. The outer rotating cover is embedded in the groove, and there is a gap between the end surface of the outer rotating cover and the bottom surface of the groove. The waterproof convex edge is embedded in the waterproof groove, and there is a gap between the side surface of the waterproof convex edge and the wall of the waterproof groove. By blocking the gap between the convex edge and the center hole, the gap between the end surface of the outer rotating cover and the bottom surface of the groove, and the gap between the waterproof convex edge and the wall of the waterproof groove, the waterproof cavity is connected to the outside of the front end of the motor, ensuring that the airflow generated by the impeller can rush out, and at the same time making the path for the outside to enter the waterproof cavity longer, avoiding the water from entering the waterproof cavity when the external water wave impacts, ensuring reliability, and the outer rotating cover, the blocking convex edge and the waterproof groove form a radial concave-convex structure, so that a large radial centrifugal force can be generated when rotating at high speed, so that the water in the gap is thrown out radially, improving the waterproof performance.

[0014] In the above-mentioned vertical milling machine, the front end of the motor has a cylindrical bearing seat, the waterproof cover is fixed on the outer end surface of the bearing seat, and the waterproof cavity is formed between the waterproof cover and the bearing seat. The bearing seat has a through hole, the motor shaft passes through the through hole of the bearing seat, and the inner rotating cover blocks the through hole of the bearing seat. The bearing seat supports the motor shaft through the bearing, and the through hole of the bearing seat is blocked by the inner rotating cover, thereby isolating the inner cavity of the motor from the waterproof cavity, playing a role of a second waterproof, and ensuring the waterproof performance of the inside of the motor.

[0015] In the vertical milling machine, the inner rotary cover has a cylindrical portion, which is inserted into the through hole of the bearing seat, and there is a gap between the outer peripheral surface of the cylindrical portion and the inner wall of the through hole. The gap between the cylindrical portion and the through hole of the bearing seat ensures that the rotation of the motor shaft is not interfered.

[0016] In the above-mentioned vertical engraving and milling machine, the air intake structure includes an air intake hole opened on the bearing seat or the waterproof cover, and the air intake hole is located at the rear side of the impeller. When the impeller rotates, the air is discharged from the front side and the air is taken in through the air intake hole at the rear side, so as to ensure smooth air flow. When the motor is in a horizontal state, the air intake hole faces upward to avoid water ingress. Of course, an air pipe can also be connected to the air intake hole to avoid water ingress.

[0017] In the vertical milling machine, the air intake structure includes strip grooves radially provided on the end surface of the bearing seat and the end surface of the waterproof cover, and the strip grooves on the end surface of the bearing seat and the end surface of the waterproof cover are relatively buckled to form an air intake hole. Processing the strip grooves on the end surface is more convenient and simple, and reduces the requirements for assembly and sealing at this location.

[0018] Compared with the existing technology, this vertical engraving and milling machine has the following advantages:

[0019] 1. Since the motor shaft drives the impeller to rotate at high speed, the impeller can generate forward airflow, and the side of the impeller where the air flows out faces the direction where the output end of the motor shaft extends. Therefore, the airflow generated by the impeller can impact the matching position of the motor shaft and the waterproof cover from the inside to the outside, thereby generating a certain air pressure between the front side of the impeller and the inside of the waterproof cover to prevent external water from penetrating from the matching position of the motor shaft and the waterproof cover, thereby improving the waterproof performance.

[0020] 2. Since the motor is sealed and waterproofed through the airflow generated by the impeller, there is no need to install traditional easily worn sealing components such as mechanical seals and sealing rings at the matching position between the motor shaft and the waterproof cover, thereby improving stability.

[0021] 3. Since the impeller is directly mounted on the motor shaft, the power of the motor itself is directly utilized, thereby simplifying the structure and making the impeller rotation always synchronized with the motor operation, ensuring the stability and reliability of the motor operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a three-dimensional structural diagram of the engraving and milling machine.

[0023] Figure 2 It is a schematic diagram of the structure of the motor after partial sectioning.

[0024] Figure 3 It is a partial structural cross-sectional view of the motor.

[0025] Figure 4 yes Figure 3 A magnified view of the structure at center.

[0026] In the figure, 1, frame; 11, base frame; 12, mounting seat; 13, column; 2, processing platform; 21, chuck; 3, positioning frame; 31, center; 4, crossbeam; 41, cross slide; 42, longitudinal slide; 43, tool holder; 5, motor; 51, motor shaft; 52, bearing seat; 521, through hole; 522, bearing chamber; 523, bearing; 524, inner cover; 6, waterproof cover; 61, waterproof cavity; 62, center hole; 63, groove; 64, waterproof convex edge; 65, air inlet; 7, impeller; 8, outer rotary cover; 81, sealing convex edge; 82, waterproof groove; 9, inner rotary cover; 91, cylindrical part. DETAILED DESCRIPTION

[0027] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0028] like Figure 1 As shown, the vertical engraving and milling machine includes a frame 1 and a processing assembly. The frame 1 includes a base frame 11 and a mounting seat 12 located on the front side of the base frame 11. A processing platform 2 is rotatably arranged on the mounting seat 12. The processing platform 2 is used to position the workpiece. Four columns 13 are fixed on the base frame 11. A long strip-shaped positioning frame 3 is vertically slidably connected between the two front columns 13. The positioning frame 3 is arranged horizontally. A downward-facing top 31 is provided on the lower side of the positioning frame 3. A chuck 21 is provided on the processing platform 2. The top 31 cooperates with the chuck 21 to clamp the workpiece. A crossbeam 4 is connected to the two rear columns 13 in a vertical sliding manner. The crossbeam 4 is arranged in the horizontal direction. A cross slide 41 is connected to the crossbeam 4 in a horizontal sliding manner. A longitudinal slide 42 is connected to the cross slide 41 in a longitudinal sliding manner. A tool holder 43 is rotatably connected to the longitudinal slide 42. The rotation center line of the tool holder 43 is arranged in the vertical direction. A processing component is arranged on the tool holder 43. The processing component includes a motor 5. The motor 5 is rotatably connected to one end of the tool holder 43. A tool is installed at the output end of the motor shaft 51 of the motor 5.

[0029] Combination Figure 2 , Figure 3As shown, the motor 5 includes a bearing seat 52 fixed at the front end, a cylindrical waterproof cover 6 is fixed at the front end of the bearing seat 52, and a seal is formed between the waterproof cover 6 and the bearing seat 52. A through hole 521 is opened on the bearing seat 52, and a center hole 62 is provided on the front end surface of the waterproof cover 6. The output end of the motor shaft 51 passes through the through hole 521 of the bearing seat 52 and the center hole 62 of the waterproof cover 6 in sequence and extends out of the waterproof cover 6 for installing a tool. The bearing seat 52 is cylindrical, and an inner cover 524 is fixed at the inner end of the bearing seat 52. A bearing chamber 522 is formed between the inner cover 524 and the bearing seat 52. A bearing 523 is installed on the motor shaft 51, and the bearing 523 is positioned in the bearing chamber 522. A waterproof cavity 61 is formed between the inner side of the waterproof cover 6 and the front end surface of the bearing seat 52. An impeller 7 is fixed on the motor shaft 51, and the impeller 7 is located in the waterproof cavity 61, and the side of the impeller 7 that discharges air faces the direction in which the output end of the motor shaft 51 extends, that is, toward the center hole 62.

[0030] Combination Figure 4As shown, the outer peripheral surface of the output end of the motor shaft 51 has an external thread, the impeller 7 is sleeved on the motor shaft 51 and fixed by threaded cooperation, and the output end of the motor shaft 51 is also sleeved with an inner rotary cover 9 and an outer rotary cover 8, both of which are disc-shaped, the inner rotary cover 9 is located in the waterproof cavity 61 and can block the through hole 521 of the bearing seat 52, the outer rotary cover 8 is located on the outer side of the front end of the waterproof cover 6 and can block the center hole 62, and the inner rotary cover 9 and the outer rotary cover 8 are both fixed to the motor shaft 51 by threaded cooperation, and the inner rotary cover 9 and the outer rotary cover 8 are respectively against the two ends of the impeller 7. The end surface of the outer rotating cover 8 has an annular sealing ridge 81 on its circumference, and the sealing ridge 81 is arranged around the motor shaft 51, and the inner circumference of the sealing ridge 81 is threadedly matched with the motor shaft 51, the sealing ridge 81 is embedded in the center hole 62 of the waterproof cover 6, and the end surface of the sealing ridge 81 is abutted against the front end of the impeller 7, and there is a gap between the outer circumference of the sealing ridge 81 and the wall of the center hole 62, and the side of the impeller 7 that outlets air faces the gap between the outer circumference of the sealing ridge 81 and the wall of the center hole 62. A circular groove 63 is provided on the outer end surface of the waterproof cover 6, and the center hole 62 is located at the center position of the bottom surface of the groove 63. A ring-shaped waterproof convex edge 64 is also circumferentially provided on the bottom surface of the groove 63, and the waterproof convex edge 64 is arranged around the center hole 62. A ring-shaped waterproof groove 82 is also circumferentially opened on the end surface of the outer rotating cover 8. The outer rotating cover 8 is embedded in the groove 63, and there is a gap between the end surface of the outer rotating cover 8 and the bottom surface of the groove 63. The waterproof convex edge 64 is embedded in the waterproof groove 82, and there is a gap between the side surface of the waterproof convex edge 64 and the groove wall of the waterproof groove 82. By blocking the gap between the convex edge 81 and the center hole 62, the gap between the end surface of the outer rotating cover 8 and the bottom surface of the groove 63, and the gap between the waterproof convex edge 64 and the groove wall of the waterproof groove 82, the outer rotating cover 8 is not in contact with the waterproof cover 6, and the waterproof cavity 61 is connected to the outside of the front end of the motor 5. The inner rotating cover 9 has a cylindrical portion 91, the inner circumference of which is threadedly matched with the motor shaft 51, and the cylindrical portion 91 is inserted into the through hole 521 of the bearing seat 52, and there is a gap between the outer circumference of the cylindrical portion 91 and the inner wall of the through hole 521. The end surface of the bearing seat 52 and the end surface of the waterproof cover 6 are both provided with strip grooves radially, and the strip grooves on the end surface of the bearing seat 52 and the strip grooves on the end surface of the waterproof cover 6 are relatively buckled to form an air inlet 65, the outer end of the air inlet 65 is connected to the outside, and the inner end is connected to the waterproof cavity 61, which is used for air intake when the impeller 7 rotates. Of course, the air inlet 65 can also be directly provided on the side of the waterproof cover 6 or on the bearing seat 52.

[0031] The specific embodiments described herein are merely examples of the spirit of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in similar ways, but they will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

[0032] Although the terms such as frame 1, base frame 11, mounting base 12 are used more frequently in this document, the possibility of using other terms is not excluded. These terms are used only to more conveniently describe and explain the essence of the present invention; interpreting them as any additional restrictions is contrary to the spirit of the present invention.

Claims

1. A vertical engraving and milling machine, comprising a frame (1) and at least one set of processing components arranged on the frame (1), wherein the processing components include a motor (5), characterized in that: A waterproof cover (6) is fixed to the front end of the motor (5), and a waterproof cavity (61) is provided on the inner side of the waterproof cover (6). An air intake structure for air intake of the waterproof cavity (61) is provided on the front end of the motor (5) or the waterproof cover (6). The output end of the motor shaft (51) for installing a tool passes through the waterproof cavity (61) and extends out of the waterproof cover (6). An impeller (7) is fixed to the motor shaft (51), and the impeller (7) is located in the waterproof cavity (61), and the side of the impeller (7) for air outlet faces the direction in which the output end of the motor shaft (51) extends out. A center hole (62) is provided on the outer end surface of the waterproof cover (6), and the output end of the motor shaft (51) extends out from the center hole (62). An outer rotating cover (8) capable of blocking the center hole (62) is also fixed to the motor shaft (51), and the outer rotating cover (8) is located outside the front end of the waterproof cover (6).

2. The vertical engraving and milling machine according to claim 1, characterized in that: The waterproof cover (6) is cylindrical, and the air outlet side of the impeller (7) is opposite to the central hole (62).

3. The vertical engraving and milling machine according to claim 2, characterized in that: The outer rotating cover (8) has an annular sealing convex edge (81) on its end surface in the circumferential direction. The sealing convex edge (81) is embedded in the central hole (62) of the waterproof cover (6), and there is a gap between the outer peripheral surface of the sealing convex edge (81) and the hole wall of the central hole (62). The air outlet side of the impeller (7) faces the gap between the outer peripheral surface of the sealing convex edge (81) and the hole wall of the central hole (62).

4. The vertical engraving and milling machine according to claim 3, characterized in that: The outer peripheral surface of the output end of the motor shaft (51) is provided with an external thread, and the impeller (7) is sleeved on the motor shaft (51) and fixed by threaded engagement.

5. The vertical engraving and milling machine according to claim 3 or 4, characterized in that: The motor shaft (51) is also sleeved with an inner rotary cover (9), and the inner rotary cover (9) and the outer rotary cover (8) are both fixed to the motor shaft (51) by threaded engagement, the impeller (7) is located between the inner rotary cover (9) and the outer rotary cover (8), and the sealing convex edges (81) of the inner rotary cover (9) and the outer rotary cover (8) respectively abut against two ends of the impeller (7).

6. The vertical engraving and milling machine according to claim 3 or 4, characterized in that: The waterproof cover (6) has a groove (63) on its outer end surface, the central hole (62) is located on the bottom surface of the groove (63), and the bottom surface of the groove (63) is also provided with an annular waterproof convex edge (64) in the circumferential direction. The end surface of the outer rotating cover (8) is also provided with an annular waterproof groove (82) in the circumferential direction. The outer rotating cover (8) is embedded in the groove (63), and a gap is formed between the end surface of the outer rotating cover (8) and the bottom surface of the groove (63). The waterproof convex edge (64) is embedded in the waterproof groove (82), and a gap is formed between the side surface of the waterproof convex edge (64) and the groove wall of the waterproof groove (82).

7. The vertical engraving and milling machine according to claim 5, characterized in that: The front end of the motor (5) is provided with a cylindrical bearing seat (52); the waterproof cover (6) is fixed on the outer end surface of the bearing seat (52); and the waterproof cavity (61) is formed between the waterproof cover (6) and the bearing seat (52); the bearing seat (52) is provided with a through hole (521); the motor shaft (51) passes through the through hole (521) of the bearing seat (52); and the inner rotary cover (9) blocks the through hole (521) of the bearing seat (52).

8. The vertical engraving and milling machine according to claim 7, characterized in that: The inner rotary cover (9) has a cylindrical portion (91), which is inserted into the through hole (521) of the bearing seat (52), and a gap is formed between the outer peripheral surface of the cylindrical portion (91) and the inner wall of the through hole (521).

9. The vertical engraving and milling machine according to claim 7, characterized in that: The air intake structure comprises an air intake hole (65) opened on the bearing seat (52) or the waterproof cover (6), and the air intake hole (65) is located on the rear side of the impeller (7).

10. The vertical engraving and milling machine according to claim 7, characterized in that: The air intake structure comprises strip grooves radially provided on the end surfaces of the bearing seat (52) and the waterproof cover (6), and the strip grooves on the end surface of the bearing seat (52) and the end surface of the waterproof cover (6) are relatively buckled to form an air intake hole (65).

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