Quasi-zero-stiffness three-degree-of-freedom vibration isolator based on air floatation and rollers

Abstract

The vibration isolator comprises a top plate, a main air chamber and a base, the main air chamber is installed in the middle of the top of the base, a first piston is installed in the main air chamber, a first swing rod is vertically installed in the first piston, arc-shaped air chambers are installed on the periphery of the main air chamber, and a second swing rod is vertically installed in the first swing rod. A second piston is installed in the arc-shaped air chamber, a second swing rod is vertically installed in the second piston, an air spring is connected to the bottom of the arc-shaped air chamber, a supporting plate is further installed between the air spring and the arc-shaped air chamber, first transverse air chambers are vertically installed on the periphery of the main air chamber, and third pistons are installed in the first transverse air chambers. The third piston is vertically connected with a first guide rod, a rolling wheel is installed on the top of the first guide rod, and the rolling wheel is in rolling connection with the arc-shaped air chamber. The device is high in positioning precision, has the bearing capacity and rigidity adjusting capacity, can adapt to precise instruments of different models, and is wide in application range and high in universality.

Description

Technical Field

[0001] The invention relates to the technical field of vibration isolation devices, in particular to an air-floating-roller quasi-zero-rigidity three-degree-of-freedom vibration isolator. Background Art

[0002] At present, the semiconductor industry is developing rapidly. The precision requirements of semiconductor production equipment are getting higher and higher, and the equipment is becoming more and more sensitive to environmental requirements such as micro-vibration. A small amount of micro-vibration will reduce the output yield of the equipment or even make the equipment unable to work normally. Therefore, the isolation of micro-vibration is becoming more and more important.

[0003] Micro-vibration caused by external environmental vibration and internal reaction force of equipment is one of the key factors restricting the measurement accuracy of ultra-precision instruments and the manufacturing accuracy of ultra-precision processing equipment. High-performance precision micro-vibration isolation technology has become a core key technology in the fields of precision engineering and ultra-precision manufacturing. The research on this technology has important practical significance and application value. The vibration frequency of interference generated by ultra-precision measuring instruments and ultra-precision processing and manufacturing equipment is mainly low-frequency vibration within 0.8 to 100 Hz. In principle, passive vibration isolators rely on reducing their natural frequency to filter out vibrations from the outside world. The vibration isolation effect depends on the size of their natural frequency. However, the natural frequency is proportional to the arithmetic square root of the stiffness of the vibration isolator, that is, the smaller the natural frequency, the smaller the stiffness. It is difficult to break through the shackles of achieving low stiffness without affecting the load-bearing capacity.

[0004] Quasi-zero stiffness isolator is a combination isolator that connects positive and negative stiffness elastic components in parallel at a static position to achieve zero stiffness. However, most quasi-zero stiffness isolators are only designed for a single vibration isolation object. Once the isolator is manufactured, the structural parameters cannot be changed. Therefore, when the isolation mass changes, such as overload or underload, the isolator no longer has the quasi-zero stiffness characteristic. A small number of isolators can still have quasi-zero stiffness characteristics under variable loads, but the isolation mass cannot change continuously. The isolator can only maintain quasi-zero stiffness at several specific masses. The scope of application is small, and generally cannot meet the vibration isolation requirements of large loads. At the same time, there are problems such as narrow vibration isolation band and poor versatility. Summary of the invention

[0005] The purpose of the present invention is to provide a three-degree-of-freedom vibration isolator based on air floating-roller quasi-zero stiffness to solve the problems existing in the above-mentioned background technology.

[0006] The technical solution of the present invention is achieved as follows: a three-degree-of-freedom vibration isolator based on air flotation-roller quasi-zero stiffness, comprising a top plate, a main air chamber and a base, wherein the main air chamber is installed in the middle of the top of the base, a piston 1 is installed inside the main air chamber, the piston 1 is connected to the main air chamber through an air film 1, a swing rod 1 is vertically installed inside the piston 1, the top of the swing rod 1 is vertically connected to the middle of the bottom of the top plate, arc-shaped air chambers are installed around the main air chamber, a piston 2 is installed inside the arc-shaped air chamber, the piston 2 is connected to the arc-shaped air chamber through an air film 2, a swing rod 2 is vertically installed inside the piston 2, the top of the swing rod 2 is vertically connected to the bottom of the top plate, an air spring is connected to the bottom of the arc-shaped air chamber, a support plate is also installed between the air spring and the arc-shaped air chamber, a transverse air chamber 1 is vertically installed around the main air chamber, a piston 3 is installed inside the transverse air chamber 1, the piston 3 is vertically connected to a guide rod 1, a roller is installed on the top of the guide rod 1, the roller is rollingly connected to the arc-shaped air chamber, and a sliding rod is installed on the top of the base. , a slider is installed on the slide bar, a metal spring 1 is set on the slide bar, the top of the metal spring 1 is fixed to the slider, the bottom of the metal spring 1 is fixed to the base, the slider is connected to the support plate, a telescopic rod is installed between the slider and the main air chamber, a metal spring 2 is installed on the telescopic rod, one end of the telescopic rod is connected to the slider through a flexible ball joint 1, and the other end of the telescopic rod is connected to the main air chamber through a flexible ball joint 2, four vertical plates are installed in a square arrangement at the bottom of the top plate, a horizontal air chamber 2 is installed between the inner side of the vertical plate and the outer side of the top of the main air chamber, a piston 4 is installed inside the horizontal air chamber 2, the piston 4 is vertically connected to a guide rod 2, the top of the guide rod 2 is connected to the vertical plate through a flexible ball joint 3, an electromagnet is installed at the bottom of the piston 4, a permanent magnet is installed at a position corresponding to the electromagnet at the bottom of the horizontal air chamber 2, a vertical voice coil motor is installed between the top of the horizontal air chamber 2 and the bottom of the top plate, an acceleration sensor and a position sensor are also installed at the bottom of the top plate, and a controller is also installed at the top of the base.

[0007] Furthermore, the main air chamber has a rectangular structure.

[0008] Furthermore, the first swing rod and the second swing rod are both flexible swing rods.

[0009] Furthermore, the arc-shaped air chamber, the support plate and the air spring are connected through air holes.

[0010] Furthermore, the air spring is installed on the top of the base.

[0011] Furthermore, a linear bearing 1 is installed between the guide rod 1 and the transverse air chamber 1, and a linear bearing 2 is installed between the guide rod 2 and the transverse air chamber 2.

[0012] Furthermore, a position control device is installed on the top of the outer side of the arc-shaped air chamber.

[0013] Furthermore, an intake pipe 1 is opened on one side of the bottom of the main air chamber, and a servo valve 1 is installed on the intake pipe 1; an intake pipe 2 is opened on one side of the bottom of the air spring, and a servo valve 2 is installed on the intake pipe 2; an intake pipe 3 is opened on one side of the bottom of the transverse air chamber 1, and a servo valve 3 is installed on the intake pipe 3; an intake pipe 4 is opened on the transverse air chamber 2, and a servo valve 4 is installed on the intake pipe 4.

[0014] Furthermore, a baffle is installed on the top of the sliding rod.

[0015] Furthermore, the controller is connected to the acceleration sensor, the position sensor, the electromagnet, and the vertical voice coil motor through cables.

[0016] The beneficial effects of the present invention are: The present invention realizes the adjustment of the positive stiffness of the system through the air pressure control of the main air chamber, and at the same time meets the load-bearing requirements of different precision instruments; the negative stiffness adjustment device is composed of the transverse air chamber 1, the roller, the arc-shaped air chamber and the air spring, and the position of the arc-shaped air chamber is adjusted by adjusting the air pressure of the air spring and cooperating with the position control device, so that the roller is at the outer vertex of the arc-shaped air chamber, and then the negative stiffness of the system is adjusted by controlling the air pressure of the transverse air chamber 1, thereby forming a positive and negative stiffness parallel system with the main air chamber, so that the system reaches static quasi-zero stiffness at the initial equilibrium position.

[0017] For a vertical high-frequency vibration source, the present invention performs the first high-frequency vibration reduction through a series system consisting of an arc air chamber and an air spring, and then realizes the second high-frequency vibration reduction through a metal spring 1, and at the same time realizes the third high-frequency vibration reduction through a metal spring 2 connected in parallel therewith; for a horizontal high-frequency vibration source, firstly, the third vibration reduction is realized through a rocker bar 1 and a rocker bar 2 connected in parallel, and then the fourth high-frequency vibration reduction is realized through a transverse air chamber 2; for a vertical low-frequency vibration source, low-frequency vibration reduction is realized through a vertical voice coil motor; for a horizontal low-frequency vibration source, low-frequency vibration reduction is realized through a magnetically driven guide rod 2, and the system vibration isolation band is relatively wide, and vibration control of 0.1 Hz to 300 Hz can be realized.

[0018] The system of the present invention has large static rigidity and large bearing capacity, which can meet the load-bearing requirements of 10,000kg precision instruments, and has high positioning accuracy. It has the ability to adjust the bearing capacity and rigidity, and can be adapted to precision instruments of different models, with a wide range of applications and strong versatility. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the present invention.

[0020] In the figure, 1-top plate, 2-main air chamber, 201-piston 1, 202-air film 1, 203-intake pipe 1, 204-servo valve 1, 3-base, 4-rocker rod 1, 5-arc-shaped air chamber, 501-piston 2, 502-air film 2, 6-rocker rod 2, 7-support plate, 8-air spring, 801-intake pipe 2, 802-servo valve 2, 9-lateral air chamber 1, 901-piston 3, 902-guide rod 1, 903-linear bearing 1, 904-roller, 905-intake pipe 2, 906-servo valve 2, 10-sliding rod, 1001-sliding block, 1002 -Metal spring one, 1003-baffle, 11-telescopic rod, 1101-metal spring two, 1102-flexible ball joint one, 1103-flexible ball joint two, 12-vertical plate, 13-transverse air chamber two, 1301-piston four, 1302-guide rod two, 1303-linear bearing two, 1304-intake pipe three, 1305-servo valve three, 14-flexible ball joint three, 15-electromagnet, 16-permanent magnet, 17-vertical voice coil motor, 18-air hole, 19-acceleration sensor, 20-position sensor, 21-controller, 22-position control device. DETAILED DESCRIPTION

[0021] The technical solution of the present invention will be described clearly and completely in conjunction with the embodiments below. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] like Figure 1As shown, a three-degree-of-freedom vibration isolator based on air flotation-roller quasi-zero stiffness includes a top plate 1, a main air chamber and a base 3, wherein the main air chamber 2 is installed in the middle of the top of the base 3, a piston 201 is installed inside the main air chamber 2, the piston 201 is connected to the main air chamber 2 through an air film 202, a swing rod 4 is vertically installed inside the piston 201, the top of the swing rod 4 is vertically connected to the middle of the bottom of the top plate 1, arc-shaped air chambers 5 are installed around the main air chamber 2, a piston 2 501 is installed inside the arc-shaped air chamber 5, the piston 2 501 is connected to the arc-shaped air chamber 5 through an air film 2 502, and the piston 2 501 is vertically installed inside the piston 2 A pendulum rod 2 6 is vertically installed, the top of the pendulum rod 2 6 is vertically connected to the bottom of the top plate 1, the bottom of the arc-shaped air chamber 5 is connected to an air spring 8, and a support plate 7 is also installed between the air spring 8 and the arc-shaped air chamber 5. The main air chamber 2 is vertically installed with a transverse air chamber 9 around it, and a piston 3 901 is installed inside the transverse air chamber 9. The piston 3 901 is vertically connected to a guide rod 1 902, and a roller 904 is installed on the top of the guide rod 1 902. The roller 904 is rollingly connected to the arc-shaped air chamber 5. A sliding rod 10 is installed on the top of the base 3, and a slider 1001 is installed on the sliding rod 10. A metal spring 1002, the top of the metal spring 1002 is fixed to the slider 1001, the bottom of the metal spring 1002 is fixed to the base 3, the slider 1001 is connected to the support plate 7, a telescopic rod 11 is installed between the slider 1001 and the main air chamber 2, a metal spring 2 1101 is installed on the telescopic rod 11, one end of the telescopic rod 11 is connected to the slider 1001 through a flexible ball joint 1102, and the other end of the telescopic rod 11 is connected to the main air chamber 2 through a flexible ball joint 2 1103, and the bottom of the top plate 1 is arranged in a square with four vertical plates 12 installed, and the inner side of the vertical plate 12 and the outer side of the top of the main air chamber 2 are connected. A transverse air chamber 2 13 is installed, a piston 4 1301 is installed inside the transverse air chamber 2 13, the piston 4 1301 is vertically connected to a guide rod 2 1303, the top of the guide rod 2 1303 is connected to the vertical plate 12 through a flexible ball joint 3 14, an electromagnet 15 is installed at the bottom of the piston 4 1301, a permanent magnet 16 is installed at a position vertically corresponding to the electromagnet 15 at the bottom of the transverse air chamber 2 13, a vertical voice coil motor 17 is installed between the top of the transverse air chamber 2 13 and the bottom of the top plate 1 respectively, an acceleration sensor 19 and a position sensor 20 are also installed at the bottom of the top plate 1, and a controller 21 is also installed at the top of the base 3.

[0023] The main air chamber 2 has a rectangular structure.

[0024] The rocker rod 1 4 and the rocker rod 2 6 are both flexible rockers.

[0025] The arc-shaped air chamber 5 , the support plate 7 , and the air spring 8 are connected through the air hole 18 .

[0026] The air spring 8 is installed on the top of the base 3 .

[0027] A linear bearing 903 is installed between the guide rod 1 902 and the transverse air chamber 1 9 , and a linear bearing 1303 is installed between the guide rod 2 1302 and the transverse air chamber 2 13 .

[0028] An intake pipe 203 is provided at one side of the bottom of the main air chamber 2, and a servo valve 204 is installed on the intake pipe 203; an intake pipe 801 is provided at one side of the bottom of the air spring 8, and a servo valve 802 is installed on the intake pipe 801; an intake pipe 905 is provided at one side of the bottom of the transverse air chamber 19, and a servo valve 906 is installed on the intake pipe 905; an intake pipe 1304 is provided on the transverse air chamber 2 13, and a servo valve 1305 is installed on the intake pipe 1304.

[0029] A baffle 1003 is also installed on the top of the sliding rod 10 .

[0030] A position control device 22 is installed on the top of the outer side of the arc-shaped air chamber 5 .

[0031] The controller 21 is connected to the acceleration sensor 19 , the position sensor 20 , the electromagnet 15 , and the vertical voice coil motor 17 via cables.

[0032] During installation, the precision instrument is placed on the top plate 2, and then the air pressure of the main air chamber 2 is controlled by adjusting the servo valve 1 204 according to the weight of the precision instrument to meet the load-bearing requirements. At the same time, the air pressure of the main air chamber 2 can be adjusted by the servo valve 1 204 to adjust the positive stiffness of the system; the air pressure of the arc air chamber 5 is adjusted by adjusting the servo valve 2 802, and the position control device 22 is used to make the roller 904 at the outer vertex of the arc air chamber 5, and then the air pressure of the lateral air chamber 1 9 is controlled by adjusting the servo valve 3 906 to adjust the negative stiffness of the system, forming a positive and negative stiffness parallel system with the main air chamber 2, and adjusting the vertical positive and negative stiffness of the system so that the system reaches a static quasi-zero stiffness at the initial equilibrium position. At this time, the metal spring 1 1002 and the metal spring 2 1101 are both in a natural telescopic state, the roller 904 is located at the outer vertex of the arc air chamber 5, and the rocker arm 2 5 is not affected by the pressure of the top plate 1.

[0033] During operation, the vibration signal is collected by the acceleration sensor 19 and the position sensor 20, and then the signal is transmitted to the controller 21. When the vibration source is vertical, the arc air chamber 5 and the air spring 8 are connected in series, and the first high-frequency vibration reduction is performed. Then, the support plate 7 moves up and down through vibration conduction, and the second high-frequency vibration reduction is achieved through the metal spring 1002. At the same time, the metal spring 2 1102 connected in parallel is stretched to achieve the third high-frequency vibration reduction. When the vibration source is vertical, the vertical voice coil motor 17 is controlled by the controller 21 to achieve low-frequency vibration reduction. When the vibration source is horizontal, the third vibration reduction is first achieved through the parallel swing rod 1 4 and swing rod 2 6, and then the fourth high-frequency vibration reduction is achieved through the horizontal air chamber 2 13. When the vibration source is horizontal, the current of the electromagnet 15 is controlled by the controller 21 to control the strength of the magnetic field between the electromagnet 15 and the permanent magnet 16, thereby driving the guide rod 2 1302 to achieve low-frequency vibration reduction.

[0034] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A three-degree-of-freedom vibration isolator based on air flotation-roller quasi-zero stiffness, comprising a top plate, a main air chamber and a base, characterized in that: The main air chamber is installed in the middle of the top of the base, and a piston 1 is installed inside the main air chamber, and the piston 1 is connected to the main air chamber through an air film 1. A swing rod 1 is vertically installed inside the piston 1, and the top of the swing rod 1 is vertically connected to the middle of the bottom of the top plate. Arc air chambers are installed around the main air chamber, and a piston 2 is installed inside the arc air chamber, and the piston 2 is connected to the arc air chamber through an air film 2. A swing rod 2 is vertically installed inside the piston 2, and the top of the swing rod 2 is vertically connected to the bottom of the top plate. An air spring is connected to the bottom of the arc air chamber, and a support plate is also installed between the air spring and the arc air chamber. A transverse air chamber 1 is vertically installed around the main air chamber, and a piston 3 is installed inside the transverse air chamber 1. A guide rod 1 is vertically connected to the piston 3, and a roller is installed on the top of the guide rod 1, and the roller is rollingly connected to the arc air chamber. A sliding rod is installed on the top of the base, and a slider is installed on the sliding rod, and a metal spring is mounted on the sliding rod 1. The top of the metal spring 1 is fixed to the slider, and the bottom of the metal spring 1 is fixed to the base. The slider is connected to the support plate. A telescopic rod is installed between the slider and the main air chamber. A metal spring 2 is installed on the telescopic rod. One end of the telescopic rod is connected to the slider through a flexible ball joint 1, and the other end of the telescopic rod is connected to the main air chamber through a flexible ball joint 2. Four vertical plates are installed in a square arrangement at the bottom of the top plate, and a horizontal air chamber 2 is installed between the inner side of the vertical plate and the outer side of the top of the main air chamber. A piston 4 is installed inside the horizontal air chamber 2, and the piston 4 is vertically connected to a guide rod 2. The top of the guide rod 2 is connected to the vertical plate through a flexible ball joint 3. An electromagnet is installed at the bottom of the piston 4. A permanent magnet is installed at a position corresponding to the electromagnet at the bottom of the horizontal air chamber 2. Vertical voice coil motors are respectively installed between the top of the horizontal air chamber 2 and the bottom of the top plate. An acceleration sensor and a position sensor are also installed at the bottom of the top plate, and a controller is also installed at the top of the base.

2. The air-floating-roller quasi-zero stiffness three-degree-of-freedom vibration isolator according to claim 1, characterized in that: The main air chamber is in a rectangular structure.

3. The air-floating-roller quasi-zero stiffness three-degree-of-freedom vibration isolator according to claim 1, characterized in that: The first swing rod and the second swing rod are both flexible swing rods.

4. The air-floating-roller quasi-zero stiffness three-degree-of-freedom vibration isolator according to claim 1, characterized in that: The arc-shaped air chamber, the support plate and the air spring are connected through air holes.

5. The air-floating-roller quasi-zero stiffness three-degree-of-freedom vibration isolator according to claim 1, characterized in that: The air spring is mounted on top of the base.

6. The air-floating-roller quasi-zero stiffness three-degree-of-freedom vibration isolator according to claim 1, characterized in that: A linear bearing 1 is also installed between the guide rod 1 and the transverse air chamber 1, and a linear bearing 2 is also installed between the guide rod 2 and the transverse air chamber 2.

7. The air-floating-roller quasi-zero stiffness three-degree-of-freedom vibration isolator according to claim 1, characterized in that: A position control device is installed on the top of the outer side of the arc-shaped air chamber. According to claim 1, a three-degree-of-freedom vibration isolator based on air flotation-roller quasi-zero stiffness isolator is characterized in that an air intake pipe 1 is opened on one side of the bottom of the main air chamber, and a servo valve 1 is installed on the air intake pipe 1; an air intake pipe 2 is opened on one side of the bottom of the air spring, and a servo valve 2 is installed on the air intake pipe 2; an air intake pipe 3 is opened on one side of the bottom of the transverse air chamber 1, and a servo valve 3 is installed on the air intake pipe 3; an air intake pipe 4 is provided on the transverse air chamber 2, and a servo valve 4 is installed on the air intake pipe 4.

8. The air-floating-roller quasi-zero stiffness three-degree-of-freedom vibration isolator according to claim 1, characterized in that: A baffle is also installed on the top of the slide bar.

9. The air-floating-roller quasi-zero stiffness three-degree-of-freedom vibration isolator according to claim 1, characterized in that: The controller is connected with the acceleration sensor, the position sensor, the electromagnet and the vertical voice coil motor through cables.

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