Air seal structure of motorized spindle

Abstract

The utility model discloses an air seal structure of an electric spindle. The air seal structure comprises a shell, a front end cover, a rotating shaft, a first labyrinth ring and a second labyrinth ring, the front end cover is connected to one end of the machine shell, the first labyrinth ring is connected to the front end cover, the rotating shaft is located in the machine shell and penetrates through the inner side of the front end cover and the inner side of the first labyrinth ring, and the rotating shaft and the front end cover are rotationally connected through a bearing. A bearing chamber used for containing the bearing is arranged between the rotating shaft and the front end cover, the second labyrinth ring is connected to the rotating shaft, the second labyrinth ring and the first labyrinth ring are matched to form a labyrinth gap, the outer periphery of the labyrinth gap is communicated with the outside, and the inner periphery of the labyrinth gap is communicated with the bearing chamber. According to the utility model, the sealing protection effect can be improved, the sealing protection performance on water and impurities is improved, and the water and the impurities can be prevented from entering the electric spindle from the gap.

Description

Technical Field

[0001] The utility model relates to an electric spindle gas seal structure. Background Art

[0002] At present, the electric spindle integrates the motor and the spindle into one, and is widely used in various processing equipment. The electric spindle has components such as a rotating shaft and a front cover. The rotating shaft needs to rotate at high speed while the front cover remains stationary, so a gap is formed between the rotating shaft and the front cover. In addition, because the use environment of the electric spindle mostly contains water and impurities, if water and impurities enter the electric spindle from the gap between the rotating shaft and the front cover, it will seriously affect the life and operation accuracy of the electric spindle. Therefore, in order to prevent water and impurities from entering the electric spindle from the gap between the rotating shaft and the front cover, many electric spindles use an air seal structure.

[0003] The air seal structure plays a role of sealing protection by blowing high-pressure air outward from the inside of the electric spindle along the gap, thereby preventing water and impurities from entering the inside of the electric spindle. For example, the Chinese patent with announcement number CN209792623U discloses an air seal structure for the front end cover of the electric spindle. However, the air seal structure of the front end cover of the electric spindle is relatively simple, and only uses high-pressure air to blow outward to prevent water and impurities from entering the electric spindle. Therefore, the sealing protection effect is poor and cannot meet the sealing protection requirements for water and impurities under complex working conditions. Utility Model Content

[0004] The technical problem to be solved by the utility model is to overcome the defects of the prior art and provide an electric spindle air seal structure, which can improve the sealing protection effect, enhance the sealing protection performance against water and impurities, and prevent water and impurities from entering the electric spindle through the gap.

[0005] In order to solve the above technical problems, the technical solution of the utility model is: an electric spindle gas seal structure, which includes a housing, a front cover, a rotating shaft, a first labyrinth ring and a second labyrinth ring;

[0006] The front end cover is connected to one end of the housing;

[0007] The first labyrinth ring is connected to the front end cover;

[0008] The rotating shaft is located in the housing and passes through the inner sides of the front end cover and the first labyrinth ring. The rotating shaft and the front end cover are rotatably connected via a bearing. A bearing chamber for accommodating the bearing is provided between the rotating shaft and the front end cover.

[0009] The second labyrinth ring is connected to the rotating shaft, and the second labyrinth ring cooperates with the first labyrinth ring to form a labyrinth gap, the outer periphery of the labyrinth gap is connected to the outside, and the inner periphery of the labyrinth gap is connected to the bearing chamber;

[0010] The casing is provided with a first air duct for introducing gas, the front end cover is provided with a second air duct connected with the first air duct, an annular air cavity connected with the second air duct is formed between the first labyrinth ring and the front end cover, the first labyrinth ring is also provided with an air guide hole connected with the annular air cavity, and the air guide hole is also connected with the middle part of the labyrinth gap.

[0011] Further provided is a specific structure of the first labyrinth ring and the second labyrinth ring, wherein a first convex ring, a second convex ring and a third convex ring are arranged in sequence from the inside to the outside on one end of the first labyrinth ring, a first ring groove is arranged between the first convex ring and the second convex ring, and a second ring groove is arranged between the second convex ring and the third convex ring;

[0012] A fourth convex ring, a fifth convex ring and a sixth convex ring are arranged in sequence from the inside to the outside on one end of the second labyrinth ring, a third ring groove is provided between the fourth convex ring and the fifth convex ring, and a fourth ring groove is provided between the fifth convex ring and the sixth convex ring;

[0013] The second convex ring is loosely fitted in the third annular groove, the third convex ring is loosely fitted in the fourth annular groove, the fourth convex ring is loosely fitted in the first annular groove, and the fifth convex ring is loosely fitted in the second annular groove.

[0014] Furthermore, a plurality of the air guide holes are evenly distributed in the circumferential direction, and the air guide holes are connected to the second annular groove.

[0015] Furthermore, the outer periphery of the first labyrinth ring is tightly sealed against the front end cover, and the first labyrinth ring is made of copper.

[0016] Furthermore, a first sealing ring is provided between the front end cover and the first labyrinth ring, which is located in the inner circumference of the annular air cavity and forms a seal between the front end cover and the first labyrinth ring.

[0017] Furthermore, a ventilation gap connected to the bearing chamber is provided between the front end cover and the rotating shaft, and the inner circumference of the labyrinth gap is connected to the ventilation gap and further connected to the bearing chamber through the ventilation gap.

[0018] In order to further position the second labyrinth ring, the rotating shaft is provided with a shoulder protruding radially outward;

[0019] The second labyrinth ring is sleeved on one end of the rotating shaft and abuts against the shaft shoulder;

[0020] At least one set screw is threadedly connected in the second labyrinth ring;

[0021] The outer side wall of the rotating shaft is provided with a tapered groove corresponding to the set screw;

[0022] One end of the set screw close to the rotating shaft is a conical head, and the conical head on the set screw is used to extend into the conical groove and press against the end of the conical groove away from the shaft shoulder, thereby driving the second labyrinth ring to press against the shaft shoulder.

[0023] A specific structure of the front end cover is further provided, wherein an axial insertion portion and a radial pressing portion are provided on an end portion of the front end cover connected to the housing;

[0024] The axial insertion portion is inserted into the housing;

[0025] The radial pressing portion is pressed against the front end surface of the housing;

[0026] One end of the second air channel is communicated with the annular air cavity, and the other end of the second air channel extends into the radial pressing portion and is communicated with the first air channel in the housing.

[0027] Furthermore, an air nozzle is embedded on the front end surface of the housing, and the radial pressing portion is pressed against the front end surface of the housing to press the air nozzle;

[0028] A connecting hole is provided in the air nozzle, one end of the connecting hole is communicated with the first air passage, and the other end of the connecting hole is communicated with the second air passage;

[0029] The gas nozzle is made of copper;

[0030] A second sealing ring surrounding the outer side of the air nozzle is provided between the front end surface of the housing and the radial pressing portion.

[0031] Furthermore, a third sealing ring is provided between the outer wall of the axial insertion portion and the housing.

[0032] After adopting the above technical solution, the first labyrinth ring is connected to the front end cover, and the second labyrinth ring is connected to the rotating shaft. When the electric spindle rotates at high speed, the rotating shaft and the second labyrinth ring rotate at high speed while the housing, the front end cover and the first labyrinth ring remain stationary. A labyrinth gap is formed between the first labyrinth ring and the second labyrinth ring. The labyrinth shape of the labyrinth gap itself has the function of blocking water and impurities from entering, thereby preventing water and impurities from entering the inside of the electric spindle. In addition, the high-pressure gas flows through the first air channel, the second air channel, the annular air cavity and the air guide hole in sequence and then flows into the middle part of the labyrinth gap. After the gas enters the labyrinth gap, a part of the airflow scatters outward along the labyrinth gap and flows to the outer ring of the labyrinth gap and blows to the outside, thereby preventing water and impurities from entering the labyrinth gap, and achieving a good air sealing effect; at the same time, after the gas enters the labyrinth gap, another part of the airflow flows inward along the labyrinth gap to the inner ring of the labyrinth gap and then flows into the bearing chamber, thereby increasing the pressure in the bearing chamber, so that water and impurities cannot enter the pressurized bearing chamber, further achieving the effect of air sealing. Therefore, the gas flows into the middle part of the labyrinth gap, achieving the dual air sealing effect of outward flow blowing and inward flow pressurization. Combined with the seal formed by the labyrinth shape of the labyrinth gap itself, the entry of water and impurities is effectively blocked, the sealing protection effect is greatly improved, the sealing protection performance against water and impurities is improved, and water and impurities are effectively prevented from entering the electric spindle from the gap. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a full cross-sectional view of the electric spindle gas seal structure of the utility model;

[0034] Figure 2 It is a half-section view of the electric spindle gas seal structure of the utility model;

[0035] Figure 3 for Figure 2 Partial detail drawing. DETAILED DESCRIPTION

[0036] In order to make the content of the utility model more clearly understood, the utility model is further described in detail below based on specific embodiments and in conjunction with the accompanying drawings.

[0037] like Figures 1 to 3 As shown, an electric spindle gas seal structure includes a housing 1, a front end cover 2, a rotating shaft 3, a first labyrinth ring 4 and a second labyrinth ring 5;

[0038] The front end cover 2 is connected to one end of the housing 1;

[0039] The first labyrinth ring 4 is connected to the front end cover 2;

[0040] The rotating shaft 3 is located in the housing 1 and passes through the inner sides of the front end cover 2 and the first labyrinth ring 4. The rotating shaft 3 and the front end cover 2 are rotatably connected via a bearing 6. A bearing chamber 7 for accommodating the bearing 6 is provided between the rotating shaft 3 and the front end cover 2.

[0041] The second labyrinth ring 5 is connected to the rotating shaft 3, and the second labyrinth ring 5 cooperates with the first labyrinth ring 4 to form a labyrinth gap 8, the outer periphery of the labyrinth gap 8 is connected to the outside, and the inner periphery of the labyrinth gap 8 is connected to the bearing chamber 7;

[0042] The housing 1 is provided with a first air passage 9 for introducing gas, the front end cover 2 is provided with a second air passage 10 communicating with the first air passage 9, an annular air cavity 11 communicating with the second air passage 10 is formed between the first labyrinth ring 4 and the front end cover 2, and an air guide hole 12 communicating with the annular air cavity 11 is also provided in the first labyrinth ring 4, and the air guide hole 12 is also communicated with the middle part of the labyrinth gap 8. Specifically, the first labyrinth ring 4 is connected to the front end cover 2, and the second labyrinth ring 5 is connected to the shaft 3. When the electric spindle rotates at high speed, the shaft 3 and the second labyrinth ring 5 rotate at high speed while the housing 1, the front end cover 2 and the first labyrinth ring 4 remain stationary. Among them, the first labyrinth ring 4 and the second labyrinth ring 5 cooperate to form a labyrinth gap 8, and the labyrinth shape of the labyrinth gap 8 itself has the function of blocking water and impurities from entering, thereby preventing water and impurities from entering the inside of the electric spindle. In addition, the high-pressure gas flows through the first air channel 9, the second air channel 10, the annular air cavity 11 and the air guide hole 12 in sequence and then flows into the middle part of the labyrinth gap 8. After the gas enters the labyrinth gap 8, a part of the airflow scatters outward along the labyrinth gap 8 and flows to the outer circle of the labyrinth gap 8 and blows to the outside, thereby preventing water and impurities from entering the labyrinth gap 8, and achieving a good air sealing effect; at the same time, after the gas enters the labyrinth gap 8, another part of the airflow flows inward along the labyrinth gap 8 to the inner circle of the labyrinth gap 8 and then flows into the bearing chamber 7, thereby increasing the pressure in the bearing chamber 7, preventing water and impurities from entering the pressurized bearing chamber 7, further achieving the effect of air sealing. Therefore, the gas flows into the middle part of the labyrinth gap 8, which plays a dual air sealing role of outward flow blowing and inward flow pressurization. Combined with the seal formed by the labyrinth shape of the labyrinth gap 8 itself, it effectively blocks the entry of water and impurities, greatly improves the sealing and protection effect, improves the sealing and protection performance against water and impurities, and effectively prevents water and impurities from entering the electric spindle through the gap.

[0043] like Figures 1 to 3As shown, a first convex ring 13, a second convex ring 14 and a third convex ring 15 are arranged on one end of the first labyrinth ring 4 in sequence from the inside to the outside, a first annular groove 16 is arranged between the first convex ring 13 and the second convex ring 14, and a second annular groove 17 is arranged between the second convex ring 14 and the third convex ring 15;

[0044] A fourth convex ring 18, a fifth convex ring 19 and a sixth convex ring 20 are arranged in sequence from the inside to the outside on one end of the second labyrinth ring 5, a third annular groove 21 is provided between the fourth convex ring 18 and the fifth convex ring 19, and a fourth annular groove 22 is provided between the fifth convex ring 19 and the sixth convex ring 20;

[0045] The second convex ring 14 is loosely fitted in the third annular groove 21, the third convex ring 15 is loosely fitted in the fourth annular groove 22, the fourth convex ring 18 is loosely fitted in the first annular groove 16, and the fifth convex ring 19 is loosely fitted in the second annular groove 17, thereby forming a labyrinth gap 8 between the first labyrinth ring 4 and the second labyrinth ring 5.

[0046] In this embodiment, there are multiple air guide holes 12 evenly distributed in sequence along the circumferential direction, and the air guide holes 12 are connected to the second annular groove 17; specifically, the gas can flow evenly from the annular air cavity 11 into the labyrinth gap 8 through the evenly distributed multiple air guide holes 12, so that the gas is evenly distributed in the labyrinth gap 8 along the circumferential direction, so as to enhance the gas sealing effect.

[0047] like Figures 1 to 3 As shown, the outer periphery of the first labyrinth ring 4 is tightly sealed against the front end cover 2, and the material of the first labyrinth ring 4 is copper; specifically, the hardness of copper is relatively low, so after the outer periphery of the first labyrinth ring 4 is tightly pressed against the front end cover 2, the abutting surface on the outer periphery of the first labyrinth ring 4 will adapt to the deformation of the front end cover 2 and then completely fit with the front end cover 2 to eliminate the gap and form a seal, thereby preventing the gas in the annular air cavity 11 from leaking from the outer end of the annular air cavity 11.

[0048] like Figures 1 to 3 As shown, a first sealing ring 23 is provided between the front end cover 2 and the first labyrinth ring 4, which is located in the inner circumference of the annular air cavity 11 and forms a seal between the front end cover 2 and the first labyrinth ring 4; specifically, the first sealing ring 23 forms a seal between the front end cover 2 and the first labyrinth ring 4, which can prevent the gas in the annular air cavity 11 from leaking from the inner end of the annular air cavity 11, thereby allowing all the gas in the annular air cavity 11 to flow from the air guide hole 12 into the labyrinth gap 8.

[0049] like Figure 3As shown, a ventilation gap 24 communicating with the bearing chamber 7 is further provided between the front end cover 2 and the rotating shaft 3 , and the inner circumference of the labyrinth gap 8 is communicated with the ventilation gap 24 and then communicated with the bearing chamber 7 through the ventilation gap 24 .

[0050] like Figure 3 As shown, the rotating shaft 3 is provided with a shoulder 25 protruding radially outward;

[0051] The second labyrinth ring 5 is sleeved on one end of the rotating shaft 3 and abuts against the shaft shoulder 25;

[0052] At least one set screw 26 is threadedly connected in the second labyrinth ring 5;

[0053] The outer wall of the rotating shaft 3 is provided with a tapered groove 27 corresponding to the set screw 26;

[0054] One end of the set screw 26 close to the rotating shaft 3 is a conical head, and the conical head on the set screw 26 is used to extend into the conical groove 27 and press against the end of the conical groove 27 away from the shaft shoulder 25, thereby driving the second labyrinth ring 5 to press against the shaft shoulder 25; in this embodiment, the second labyrinth ring 5 is provided with a plurality of the set screws 26 evenly distributed along the circumferential direction, and the conical groove 27 corresponds to the set screws 26 one by one, and the cooperation of the set screws 26 and the conical groove 27 can drive the second labyrinth ring 5 to press against the shaft shoulder 25, and then the position of the second labyrinth ring 5 can be accurately located through the shaft shoulder 25, and then the size of the labyrinth gap 8 between the first labyrinth ring 4 and the second labyrinth ring 5 can be accurately controlled, so that the size of the labyrinth gap 8 remains accurate and uniform, and then the performance of the labyrinth gap 8 in blocking water and impurities can be guaranteed, thereby ensuring the sealing effect. In addition, after the position of the second labyrinth ring 5 is accurately positioned, a safe distance can be left between the second labyrinth ring 5 and the cone handle, thereby preventing the second labyrinth ring 5 from affecting the use of the cone handle.

[0055] like Figure 1 , 2 As shown, an axial insertion portion 28 and a radial pressing portion 29 may be provided on one end of the front end cover 2 connected to the housing 1;

[0056] The axial insertion portion 28 is inserted into the housing 1;

[0057] The radial pressing portion 29 is pressed against the front end surface of the housing 1;

[0058] One end of the second air channel 10 is communicated with the annular air cavity 11 , and the other end of the second air channel 10 extends into the radial pressing portion 29 and is communicated with the first air channel 9 in the housing 1 .

[0059] like Figure 1 , 2 As shown, a gas nozzle 30 is embedded on the front end surface of the housing 1, and the radial pressing portion 29 is pressed against the front end surface of the housing 1 and presses the gas nozzle 30;

[0060] The air nozzle 30 is provided with a connecting hole 31, one end of the connecting hole 31 is communicated with the first air passage 9, and the other end of the connecting hole 31 is communicated with the second air passage 10;

[0061] The gas nozzle 30 is made of copper;

[0062] A second sealing ring 32 surrounding the outside of the air nozzle 30 is provided between the front end surface of the housing 1 and the radial clamping portion 29; specifically, since the hardness of copper is relatively low, the air nozzle 30 will be deformed after the radial clamping portion 29 presses the air nozzle 30. After the deformation, the air nozzle 30 is completely fitted with the housing 1 and the radial clamping portion 29 respectively to eliminate the gap and form a seal, thereby preventing gas leakage; on this basis, a second sealing ring 32 is also provided on the outside of the air nozzle 30 to form a double seal, which further improves the sealing performance to prevent air leakage.

[0063] like Figure 1 , 2 As shown, a third sealing ring 33 is provided between the outer wall of the axial insertion portion 28 and the casing 1; specifically, by providing the first sealing ring 23, the second sealing ring 32 and the third sealing ring 33, a seal is formed by deforming the air nozzle 30, and the outer periphery of the first labyrinth ring 4 is tightly sealed against the front end cover 2, which can prevent leakage of high-pressure gas, thereby greatly reducing gas seal leakage, and enhancing the stability of the airflow and the effect of the labyrinth seal.

[0064] In this embodiment, the second air duct 10 includes a first hole portion 34 extending axially, a second hole portion 35 extending radially, and a third hole portion 36 extending axially; wherein, one end of the first hole portion 34 is connected to the annular air cavity 11, and the other end of the first hole portion 34 is connected to one end of the second hole portion 35, and a steel ball 37 is provided in the other end of the second hole portion 35 for sealing, and the third hole portion 36 is provided in the radial clamping portion 29, and one end of the third hole portion 36 is connected to the second hole portion 35, and the other end of the third hole portion 36 is connected to the connecting hole 31.

[0065] In summary, the first labyrinth ring 4 is connected to the front end cover 2, and the second labyrinth ring 5 is connected to the rotating shaft 3. When the electric spindle rotates at high speed, the rotating shaft 3 and the second labyrinth ring 5 rotate at high speed while the housing 1, the front end cover 2 and the first labyrinth ring 4 remain stationary. A labyrinth gap 8 is formed between the first labyrinth ring 4 and the second labyrinth ring 5. The labyrinth shape of the labyrinth gap 8 has the function of blocking water and impurities from entering, thereby preventing water and impurities from entering the inside of the electric spindle. In addition, the high-pressure gas flows through the first air channel 9, the second air channel 10, the annular air cavity 11 and the air guide hole 12 in sequence and then flows into the middle part of the labyrinth gap 8. After the gas enters the labyrinth gap 8, a part of the airflow scatters outward along the labyrinth gap 8 and flows to the outer circle of the labyrinth gap 8 and blows to the outside, thereby preventing water and impurities from entering the labyrinth gap 8, and achieving a good air sealing effect; at the same time, after the gas enters the labyrinth gap 8, another part of the airflow flows inward along the labyrinth gap 8 to the inner circle of the labyrinth gap 8 and then flows into the bearing chamber 7, thereby increasing the pressure in the bearing chamber 7, preventing water and impurities from entering the pressurized bearing chamber 7, further achieving the effect of air sealing. Therefore, the gas flows into the middle part of the labyrinth gap 8, which plays a dual air sealing role of outward flow blowing and inward flow pressurization. Combined with the seal formed by the labyrinth shape of the labyrinth gap 8 itself, it effectively blocks the entry of water and impurities, greatly improves the sealing and protection effect, improves the sealing and protection performance against water and impurities, and effectively prevents water and impurities from entering the electric spindle through the gap.

[0066] The specific embodiments described above further illustrate the technical problems, technical solutions and beneficial effects solved by the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An electric spindle gas seal structure, It is characterized in that It comprises a housing (1), a front end cover (2), a rotating shaft (3), a first labyrinth ring (4) and a second labyrinth ring (5); The front end cover (2) is connected to one end of the housing (1); The first labyrinth ring (4) is connected to the front end cover (2); The rotating shaft (3) is located in the housing (1) and passes through the inner sides of the front end cover (2) and the first labyrinth ring (4); the rotating shaft (3) and the front end cover (2) are rotatably connected via a bearing (6); a bearing chamber (7) for accommodating the bearing (6) is provided between the rotating shaft (3) and the front end cover (2); The second labyrinth ring (5) is connected to the rotating shaft (3), and the second labyrinth ring (5) cooperates with the first labyrinth ring (4) to form a labyrinth gap (8), the outer periphery of the labyrinth gap (8) is connected to the outside, and the inner periphery of the labyrinth gap (8) is connected to the bearing chamber (7); The housing (1) is provided with a first air passage (9) for introducing gas, the front end cover (2) is provided with a second air passage (10) connected to the first air passage (9), an annular air cavity (11) connected to the second air passage (10) is formed between the first labyrinth ring (4) and the front end cover (2), the first labyrinth ring (4) is also provided with an air guide hole (12) connected to the annular air cavity (11), and the air guide hole (12) is also connected to the middle part of the labyrinth gap (8).

2. The electric spindle gas seal structure according to claim 1, It is characterized in that A first convex ring (13), a second convex ring (14) and a third convex ring (15) are arranged in sequence from the inside to the outside on one end of the first labyrinth ring (4); a first annular groove (16) is provided between the first convex ring (13) and the second convex ring (14); and a second annular groove (17) is provided between the second convex ring (14) and the third convex ring (15); A fourth convex ring (18), a fifth convex ring (19) and a sixth convex ring (20) are arranged in sequence from the inside to the outside on one end of the second labyrinth ring (5); a third annular groove (21) is provided between the fourth convex ring (18) and the fifth convex ring (19); and a fourth annular groove (22) is provided between the fifth convex ring (19) and the sixth convex ring (20); The second convex ring (14) is loosely fitted in the third annular groove (21), the third convex ring (15) is loosely fitted in the fourth annular groove (22), the fourth convex ring (18) is loosely fitted in the first annular groove (16), and the fifth convex ring (19) is loosely fitted in the second annular groove (17).

3. The electric spindle gas seal structure according to claim 2, It is characterized in that A plurality of the air guide holes (12) are evenly distributed in sequence along the circumferential direction, and the air guide holes (12) are in communication with the second annular groove (17).

4. The electric spindle gas seal structure according to claim 1, It is characterized in that The outer periphery of the first labyrinth ring (4) is tightly sealed against the front end cover (2), and the material of the first labyrinth ring (4) is copper.

5. The electric spindle gas seal structure according to claim 1, It is characterized in that A first sealing ring (23) is provided between the front end cover (2) and the first labyrinth ring (4), which is located in the inner circumference of the annular air cavity (11) and forms a seal between the front end cover (2) and the first labyrinth ring (4).

6. The electric spindle gas seal structure according to claim 1, It is characterized in that A ventilation gap (24) communicating with the bearing chamber (7) is also provided between the front end cover (2) and the rotating shaft (3); the inner peripheral portion of the labyrinth gap (8) is communicated with the ventilation gap (24) and further communicated with the bearing chamber (7) through the ventilation gap (24).

7. The electric spindle gas seal structure according to claim 1, It is characterized in that The rotating shaft (3) is provided with a shaft shoulder (25) protruding radially outward; The second labyrinth ring (5) is sleeved on one end of the rotating shaft (3) and abuts against the shaft shoulder (25); At least one set screw (26) is threadedly connected in the second labyrinth ring (5); The outer wall of the rotating shaft (3) is provided with a tapered groove (27) corresponding to the set screw (26); The end of the set screw (26) close to the rotating shaft (3) is a conical head, and the conical head on the set screw (26) is used to extend into the conical groove (27) and press against the end of the conical groove (27) away from the shaft shoulder (25), thereby driving the second labyrinth ring (5) to press against the shaft shoulder (25).

8. The electric spindle gas seal structure according to claim 1, It is characterized in that An axial insertion portion (28) and a radial pressing portion (29) are provided on one end portion of the front end cover (2) connected to the housing (1); The axial insertion portion (28) is inserted into the housing (1); The radial pressing portion (29) is pressed against the front end surface of the casing (1); One end of the second air channel (10) is in communication with the annular air cavity (11), and the other end of the second air channel (10) extends into the radial pressing portion (29) and is in communication with the first air channel (9) in the housing (1).

9. The electric spindle gas seal structure according to claim 8, It is characterized in that An air nozzle (30) is embedded on the front end surface of the housing (1), and the radial pressing portion (29) abuts against the front end surface of the housing (1) and presses the air nozzle (30); The air nozzle (30) is provided with a connecting hole (31), one end of the connecting hole (31) is in communication with the first air passage (9), and the other end of the connecting hole (31) is in communication with the second air passage (10); The gas nozzle (30) is made of copper; A second sealing ring (32) surrounding the outer side of the air nozzle (30) is provided between the front end surface of the housing (1) and the radial pressing portion (29).

10. The electric spindle gas seal structure according to claim 8, It is characterized in that A third sealing ring (33) is provided between the outer wall of the axial insertion portion (28) and the housing (1).

Images