80,000 r / min ultrasonic air static pressure electric spindle

Abstract

An ultrasonic air static pressure electric spindle of 80,000 revolutions / min comprises a shell and a rotating shaft located in the shell and driven by a motor, the rotating shaft is provided with a shaft shoulder, axial bearings used for providing axial rigidity for the rotating shaft are arranged on the two sides, close to the shaft shoulder, in the shell, and the shaft shoulder is located in the middle of the rotating shaft. A front radial bearing for supporting the rotating shaft is arranged on the left side of the shaft shoulder in the shell, a rear radial bearing for supporting the rotating shaft is arranged on the right side of the shaft shoulder in the shell, and the front radial bearing and the rear radial bearing are both used for providing radial rigidity for the rotating shaft; on the premise that the radial rigidity of the rotating shaft is guaranteed, the overall length of the main shaft is shortened, and the requirement for high-speed rotation of the rotating shaft body is met.

Description

Technical Field

[0001] The utility model relates to the field of electric spindles, in particular to an ultrasonic gas static pressure electric spindle with a rotation speed of 80,000 revolutions per minute. Background Art

[0002] Ultrasonic pneumatic electric spindles are often used in the field of mechanical processing. They drive workpieces or tools to cut at high speeds. Ultrasonic pneumatic electric spindles do not have ultrasonic power supplies and transducers like traditional ultrasonic spindles. The ultrasonic device is built into the shaft to stop and start the ultrasonic wave. The shaft is in an air suspension state through ultrasonic vibration and air intake, thus having the advantages of high speed, high precision and long life.

[0003] The applicant previously applied for an ultrasonic gas static pressure permanent magnet synchronous electric spindle for semiconductor wafer grinding, with application number: CN202022644251.7. The spindle shaft shoulder is located on the spindle body close to its left end, and its two sides are supported by two axial bearings respectively, while the part of the spindle body located on the right side of the shoulder is supported by radial bearings. In order to ensure the radial stiffness of the spindle body, a longer radial bearing is required, resulting in a longer overall spindle length and excessive occupation of working space during use. Once the length of the radial bearing is shortened, the radial stiffness cannot be guaranteed, making the spindle body unable to meet the requirements of high-speed rotation. Utility Model Content

[0004] The utility model aims to provide an ultrasonic gas static pressure electric spindle with a speed of 80,000 revolutions per minute to increase the rotating speed of a rotating shaft.

[0005] In order to solve the above technical problems, the specific solution adopted by the utility model is:

[0006] An ultrasonic pneumatic electric spindle with a speed of 80,000 rpm comprises a shell and a rotating shaft driven by a motor in the shell, the rotating shaft having a shoulder, and axial bearings for providing axial rigidity to the rotating shaft are arranged on both sides of the shell adjacent to the shoulder for the shaft, the shoulder is located in the middle of the rotating shaft, front radial bearings for supporting the rotating shaft are arranged on the left side of the shoulder in the shell, and rear radial bearings for supporting the rotating shaft are arranged on the right side of the shoulder in the shell, and both the front radial bearing and the rear radial bearing are used to provide radial rigidity of the rotating shaft.

[0007] The motor comprises a motor rotor used in conjunction with a rotating shaft and a motor stator used to drive the motor rotor to drive the rotating shaft to rotate. The motor inlet line of the motor passes through the rear of the housing and is electrically connected to an external power source.

[0008] A cooling water jacket for cooling the motor is arranged in the shell, and a cooling water inlet and a cooling water outlet are symmetrically arranged on the end surface of the rear portion of the shell. The cooling water enters the cooling water jacket through the cooling water inlet and then circulates to the cooling water outlet to flow out.

[0009] An air path interconnected with each other is provided inside the shell, an air inlet for supplying air to the air path is provided at the rear of the shell, a through hole is provided on the first front radial bearing, the air path is connected to the through hole on the first front radial bearing through the air intake of the first front radial bearing, and the gas in the air inlet passes through the through hole to form an air film on the outside of the rotating shaft to support the part of the rotating shaft corresponding to the first front radial bearing.

[0010] A second front radial bearing air intake is provided between the air circuit and the second front radial bearing. The second front radial bearing air intake is connected to the air circuit. A through hole is provided on the second front radial bearing. The second front radial bearing air intake supplies air through the through hole of the second front radial bearing through the air circuit to form an air film at the shaft shoulder to support the part of the rotating shaft corresponding to the second front radial bearing.

[0011] An axial bearing air inlet connected to the air circuit is provided, and a through hole is provided on the axial bearing. The axial bearing air inlet supplies air through the through hole on the axial bearing through the air circuit to form an air film on one side between the axial bearing and the shaft shoulder to support the corresponding part of the rotating shaft and the axial bearing.

[0012] The outer circumferential surface of the rear radial bearing is provided with grooves at intervals, the grooves are connected to each other by connecting grooves, a through hole penetrating the rear radial bearing is provided in the groove, a rear radial bearing air inlet is provided on the air path, and the rear radial bearing air inlet supplies air through the through hole of the rear radial bearing through the air path to form an air film between the tail of the rotating shaft and the rear radial bearing to support the part of the rotating shaft corresponding to the rear radial bearing.

[0013] There are two front radial bearings, namely a first front radial bearing and a second front radial bearing. The axial bearing close to one side of the second front radial bearing is connected to the second front radial bearing.

[0014] Due to the adoption of the above technical solution, the utility model has the following beneficial effects:

[0015] By setting the shoulder of the rotating shaft in the middle of the rotating shaft and installing the front radial bearing and the rear radial bearing on both sides of the shoulder, the two sides of the rotating shaft are supported and the radial stiffness of the rotating shaft is guaranteed. When the rotating shaft is supported and the radial stiffness is guaranteed, the length of the radial bearing can be reduced, thereby shortening the overall length of the main shaft while ensuring the radial stiffness of the rotating shaft and meeting the requirements of high-speed rotation of the rotating shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a top view of the utility model;

[0017] Figure 2 It is a front view of the utility model;

[0018] Figure 3 It is a side view of the utility model;

[0019] Housing 1; shaft 2; first front radial bearing 3; air inlet 4; rear radial bearing air inlet 5; axial bearing air inlet 6; second front radial bearing air inlet 7; first front radial bearing air inlet 8; cooling water inlet 9; cooling water outlet 10; motor rotor 11; motor stator 12; cooling water jacket 13; motor inlet 14; shaft shoulder 15; rear radial bearing 16; groove 17; second front radial bearing 18; axial bearing 19. DETAILED DESCRIPTION

[0020] The utility model is different from the prior application mentioned in the background technology in that the utility model installs radial bearings on both sides of the shoulder 15 by setting the shoulder 15 of the rotating shaft 2 in the middle of the rotating shaft 2. Since the radial bearings are installed on both sides of the shoulder 15, the radial stiffness of the rotating shaft 2 can be effectively guaranteed, and the length of the radial bearing can be shortened, thereby increasing the rotation speed of the rotating shaft 2.

[0021] like Figure 1 and Figure 2 As shown, an 80,000 rpm ultrasonic gas static pressure electric spindle includes a housing 1, a rotating shaft 2 is arranged inside the housing 1, one end of the rotating shaft 2 is used as an output shaft to cooperate with a fixture to drive the workpiece to rotate, and the other end of the rotating shaft 2 is located inside the housing 1 as a driving shaft and is driven by the motor inside the housing 1. A first front radial bearing 3, a second front radial bearing 18 and a rear radial bearing 16 are arranged inside the housing 1 in sequence, and the first front radial bearing 3, the second front radial bearing 18 and the rear radial bearing 16 are all radial bearings used to support the transmission of the rotating shaft 2, and the rotating shaft 2 passes through the first front radial bearing 3, the second front radial bearing 18 and the rear radial bearing 16 in sequence. The shoulder 15 of the rotating shaft 2 is located in the middle of the rotating shaft 2, and an axial bearing 19 is provided in the outer shell 1. The axial bearings 19 are respectively located on both sides of the rotating shaft 2. The axial bearing 19 on the side of the shoulder 15 close to the second front radial bearing 18 is connected to the second front radial bearing 18. The function of the axial bearing 19 is to prevent the rotating shaft 2 from moving along the axial direction in the outer shell 1, so as to ensure that the rotating shaft 2 can provide stable power output when rotating.

[0022] like Figure 2 and Figure 3As shown, the motor includes a motor rotor 11 and a motor stator 12. The motor rotor 11 is connected to the rotating shaft 2. The rotating shaft 2 is driven to rotate by the cooperation of the motor stator 12 and the motor rotor 11. The motor input line 14 of the motor passes through the tail of the housing 1, and the motor input line 14 can be connected to an external power supply.

[0023] like Figure 2 As shown, a cooling water jacket 13 for cooling the motor is provided in the housing 1. The cooling water jacket 13 is wrapped around the outside of the motor to cool the motor. A cooling water inlet 9 and a cooling water outlet 10 are symmetrically provided on the end face of the rear end of the housing 1. The cooling water enters the cooling water jacket 13 from the cooling water inlet 9, and flows out from the cooling water outlet 10 after cooling the motor, thereby completing the cooling of the motor.

[0024] like Figure 1 As shown, an air path is provided inside the housing 1, and an air inlet 4 for supplying air to the air path is provided at the rear of the housing 1. The air entering the air inlet 4 travels along the air path. A through hole is provided on the first front radial bearing 3. The air path is connected to the through hole on the first front radial bearing 3 through the first front radial bearing air inlet 8. The gas in the air inlet 4 passes through the through hole along the air path to form an air film on the outside of the rotating shaft 2. The friction generated between the rotating shaft 2 and the first front radial bearing 3 is reduced by forming the air film. A second front radial bearing air inlet 7 is provided between the air path and the second front radial bearing 18. The second front radial bearing air inlet 7 is connected to the air path. A through hole is provided on the second front radial bearing 18. The through hole passes through the surface of the second front radial bearing 18. The second front radial bearing air inlet 7 supplies air through the through hole of the second front radial bearing 18 through the air path to form an air film at the shaft shoulder 15 to support the connecting part between the rotating shaft 2 and the second front radial bearing 18. An axial bearing air inlet 6 is provided between the axial bearing 19 and the air path. The axial bearing 19 is provided with a through hole. The axial bearing air inlet 6 supplies air through the through hole on the axial bearing 19 through the air path to form a side air film between the axial bearing 19 and the shaft shoulder 15 to support the part between the rotating shaft 2 and the axial bearing 19. The outer peripheral surface of the rear radial bearing 16 is provided with grooves 17 spaced from each other. The grooves 17 are connected to each other through a connecting groove. The grooves 17 are provided with a through hole penetrating the rear radial bearing 16. The air path is provided with a rear radial bearing air inlet 5. The rear radial bearing air inlet 5 supplies air through the through hole of the rear radial bearing 16 through the air path to form a layer of air film between the tail of the rotating shaft 2 and the rear radial bearing 16 to provide support. The radial bearing and the axial bearing used in the utility model are both air bearings. The air path connects the rear radial bearing air inlet 5, the axial bearing air inlet 6, the second front radial bearing air inlet 7 and the first front radial bearing air inlet 8 to each other, so that air is supplied to them through the air inlet 4.

[0025] The following is a brief description of the method of use of the utility model: the motor is powered by the motor inlet 14 to start working. When the motor is working, it drives the shaft 2 to rotate. During the rotation of the shaft 2, it will be transmitted through the first front radial bearing 3, the rear radial bearing 16 and the second front radial bearing 18. Since the shoulder 15 is set in the middle of the shaft 2, and radial bearings are set on the left and right of the shoulder 15, the shaft 2 can not only be supported by the radial bearing to ensure radial stiffness, but also can reduce the length of the radial bearing, so as to achieve a higher shaft speed. The axial bearings 19 on both sides of the shoulder 15 can prevent the shaft 2 from moving axially during rotation. The air circuit supplies air to each bearing through the rear radial bearing air inlet 5, the axial bearing air inlet 6, and the second front radial bearing air inlet 7, so as to form an air film to support between the shaft 2 and each bearing.

Claims

1. An ultrasonic pneumatic electric spindle with a speed of 80,000 revolutions per minute, comprising a housing (1) and a rotating shaft (2) located in the housing (1) and driven by a motor, the rotating shaft (2) having a shaft shoulder (15), and axial bearings (19) for providing axial rigidity to the rotating shaft (2) are provided on both sides of the housing (1) adjacent to the shaft shoulder (15), wherein the characteristics are: The shaft shoulder (15) is located in the middle of the rotating shaft (2); a front radial bearing for supporting the rotating shaft (2) is provided on the left side of the shaft shoulder (15) in the housing (1); a rear radial bearing (16) for supporting the rotating shaft (2) is provided on the right side of the shaft shoulder (15) in the housing (1); the front radial bearing and the rear radial bearing (16) are both used to provide radial stiffness of the rotating shaft (2).

2. The ultrasonic gas static pressure electric spindle with a speed of 80,000 rpm according to claim 1 is characterized by: The motor comprises a motor rotor (11) used in conjunction with a rotating shaft (2) and a motor stator (12) used to drive the motor rotor (11) to drive the rotating shaft (2) to rotate. A motor input line (14) of the motor passes through the rear end of the housing (1) and is electrically connected to an external power source.

3. The ultrasonic gas static pressure electric spindle with a speed of 80,000 rpm according to claim 1 is characterized by: A cooling water jacket (13) for cooling the motor is provided in the housing (1), and a cooling water inlet (9) and a cooling water outlet (10) are symmetrically provided on the end surface of the rear portion of the housing (1). The cooling water enters the cooling water jacket (13) through the cooling water inlet (9) and then circulates to the cooling water outlet (10) before flowing out.

4. The ultrasonic gas static pressure electric spindle with a speed of 80,000 rpm according to claim 1 is characterized by: The front radial bearing comprises a first front radial bearing (3) and a second front radial bearing (18) which are spaced apart from each other. An air path which is interconnected is provided inside the housing (1). An air inlet (4) for supplying air to the air path is provided at the rear of the housing (1). A through hole is provided on the first front radial bearing (3). The air path is connected to the through hole on the first front radial bearing (3) through the first front radial bearing air inlet (8). The gas in the air inlet (4) passes through the through hole to form an air film on the outside of the rotating shaft (2) to support the part of the rotating shaft (2) corresponding to the first front radial bearing (3).

5. The ultrasonic gas static pressure electric spindle with a speed of 80,000 rpm according to claim 4 is characterized by: A second front radial bearing air inlet (7) is provided between the air circuit and the second front radial bearing (18), the second front radial bearing air inlet (7) is connected to the air circuit, a through hole is provided on the second front radial bearing (18), and the second front radial bearing air inlet (7) supplies air through the through hole of the second front radial bearing (18) through the air circuit to form an air film at the shaft shoulder (15) to support the portion of the rotating shaft (2) corresponding to the second front radial bearing (18).

6. The ultrasonic gas static pressure electric spindle with a speed of 80,000 rpm according to claim 4 is characterized by: An axial bearing air inlet (6) connected to the air path is provided between the axial bearing (19), and a through hole is provided on the axial bearing (19). The axial bearing air inlet (6) supplies air through the air path to pass through the through hole on the axial bearing (19) to form an air film on one side between the axial bearing (19) and the shaft shoulder (15) to support the corresponding part of the rotating shaft (2) and the axial bearing (19).

7. The ultrasonic gas static pressure electric spindle with a speed of 80,000 rpm according to claim 4 is characterized by: The outer circumferential surface of the rear radial bearing (16) is provided with grooves (17) at intervals, the grooves (17) are connected to each other through connecting grooves, a through hole penetrating the rear radial bearing (16) is provided in the groove (17), a rear radial bearing air inlet (5) is provided on the air path, and the rear radial bearing air inlet (5) supplies air through the through hole of the rear radial bearing (16) through the air path to form an air film between the tail of the rotating shaft (2) and the rear radial bearing (16) to support the corresponding part of the rotating shaft (2) and the rear radial bearing (16).

8. The ultrasonic gas static pressure electric spindle with a speed of 80,000 rpm according to claim 1 is characterized by: The number of the front radial bearings is two, namely a first front radial bearing (3) and a second front radial bearing (18), and an axial bearing (19) close to one side of the second front radial bearing (18) is connected to the second front radial bearing (18).

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