Magnetically preloaded air bearing and linear platform comprising same

Abstract

A magnetically preloaded air bearing, comprising an air bearing base (1). A plurality of pre-loading assemblies (2) are arranged around the air bearing base (1), an annular air bearing structure (11) extends and protrudes from one side of the air bearing base (1), an air inlet channel (12) extends through the other side of the air bearing base (1), a flow distribution assembly (3) is provided in the air bearing base (1), the side edge of the flow distribution assembly (3) is arranged corresponding to the inner side of the air bearing structure (11), and the air inlet channel (12) is arranged corresponding to the flow distribution assembly (3); and the pre-loading assemblies (2) are connected to the air bearing base (1) by means of fixing rods (22). The magnetically preloaded air bearing and a linear platform comprising same have high stability and high precision, and are not prone to generation of the air hammer effect.

Description

Magnetic preloaded air bearing and linear platform with the bearing Technical Field

[0001] The invention belongs to the technical field of precision instruments, and in particular relates to a magnetic preloaded air bearing and a linear platform having the bearing. Background Art

[0002] Air bearings are sliding bearings that use air as a lubricant. During normal operation, the shaft and bearing surfaces are completely separated by an air film, which supports the shaft and external loads by varying pressure within the air film. To achieve greater rigidity in air bearings, a high load, or preload, is generally required. This is particularly true for lateral air bearings, which require additional preload. Common preloading methods include vacuum preloading and magnetic preloading. Vacuum preloading has more stringent application conditions and a relatively low preload force. Magnetic preloading is generally used to load air bearings.

[0003] Prior art includes the invention patent entitled "Self-pressurizing floating gas bearing having a magnetic bearing therein," published as US Patent No. 4128280A. This invention provides a composite bearing comprising a self-pressurizing floating gas bearing and a permanent magnet bearing. The permanent magnet bearing supports the bearing body in a spaced relationship from the support body, at least during the startup period from a stationary state to the time the bearing body descends to its stationary position. The bearing can be configured as a radial bearing or a thrust bearing. The permanent magnet bearing can be located inside or outside the gas bearing. However, this invention exhibits slightly lower stability.

[0004] Summary of the Invention

[0005] The object of the present invention is to provide a magnetic preloaded air bearing with high stability, high precision and no tendency to generate air hammer, and a linear platform having the bearing.

[0006] The technical solutions adopted by the present invention to achieve the above-mentioned purpose are:

[0007] A magnetic preloaded air-floating bearing comprises an air-floating base, with a plurality of preload components arranged around the air-floating base. An annular air-floating structure is extended and protruded from one side of the air-floating base, and an air inlet channel is extended through the other side of the air-floating base. A diverter component is arranged in the air-floating base, and the side of the diverter component is arranged correspondingly to the inner side of the air-floating structure, and the air inlet channel is arranged correspondingly to the diverter component; the preload component is connected to the air-floating base through a fixing rod.

[0008] According to an embodiment of the present invention, the air floating structure adopts a porous throttling material.

[0009] Through the overall setting of the magnetic preloaded air-floating bearing, the external air source will enter the air-floating matrix through the air inlet channel, and the gas transported in the air inlet channel will enter the diversion component. The diversion component is used to realize the gas diversion in two directions, one direction is toward the air-floating structure, and the other direction is toward the air-floating guide rail. The air-floating structure adopts a porous throttling material. The porous throttling material has a solid matrix and mutually interpenetrating pores. The gas will be throttled through the porous throttling material and flow into the space between the porous throttling material and the air-floating guide rail, forming a layer of gas between the porous throttling material and the air-floating guide rail. The air film is used to suspend the air flotation guide rail and the porous throttling material. Since the air flotation structure is an annular structure protruding from one side of the air flotation base, a groove can be provided on one side of the air flotation base. In other words, the diverter component in the groove discharges the gas toward the air flotation guide rail, thereby maintaining the gas pressure and giving the gas pressure a certain elastic range. In other words, when the pressure of the gas delivered by the external gas source fluctuates, the gas can be stored and released in the groove to stabilize the pressure fluctuation in the groove and ensure that the formation and thickness of the air film are not affected, thereby preventing the occurrence of air hammer. By setting the diverter component, multiple exhaust directions can be formed, which helps to discharge the gas and improve the fluency of the exhaust.

[0010] The air-floating base is surrounded by a plurality of preload components, and the preload components are provided with magnetic attraction. The preload components are used to cooperate with the air-floating guide rail, that is, an adsorption strip or other magnetic attraction device compatible with the preload component is provided opposite to the air-floating guide rail, so that the magnetic preload air-floating bearing may be unstable during its movement, such as the air-floating bearing shaking, tilting, etc. The preload components arranged around the air-floating base form a force with the air-floating guide rail through magnetic attraction, which helps to improve the stability of the magnetic preload air-floating bearing during operation; when the external air source stops supplying air, the setting of the preload component can quickly adsorb with the air-floating guide rail to stop the movement of the air-floating platform, reduce or avoid movement errors, and improve the response efficiency and speed of braking.

[0011] According to one embodiment of the present invention, a slow flow component is provided at the end of the air inlet channel, and the slow flow component is arranged in cooperation with the diversion component. The slow flow component includes a first slow flow shell, and the end of the air inlet channel is arranged through the top of the first slow flow shell, and air holes are arranged laterally around the first slow flow shell; a fixed barrel is coaxially provided in the first slow flow shell, and air holes are provided on the side of the fixed barrel, and the bottom side of the fixed barrel is arranged corresponding to the bottom side of the first slow flow shell, and a limiting ring is extended to the opposite side of the bottom side of the fixed barrel and the bottom side of the first slow flow shell, and a rubber plug that can slide axially along the first slow flow shell is provided on the opposite side of the fixed barrel and the first slow flow shell, and a first spring is provided on one side of the rubber plug, and the other side of the first spring is connected to the top side inside the first slow flow shell.

[0012] Through the above design, after the gas enters the first slow-flow housing from the air inlet channel, it is temporarily stored in the first slow-flow housing before being discharged from the air vent into the diverter assembly. The slow-flow assembly is used to provide a buffer for the gas after it enters the air flotation matrix. Because a rubber plug and a first spring are provided in the first slow-flow housing, wherein the rubber plug can slide and move along the axial direction of the first slow-flow housing, the rubber plug and the first spring can cooperate to control the airflow space inside the first slow-flow housing, thereby controlling the air pressure inside the first slow-flow housing and, in turn, the air pressure of the gas discharged from the air vent, thereby avoiding the situation where the air pressure value is lost during the long air pipe transportation process.

[0013] According to an embodiment of the present invention, a second flow slowdown shell is correspondingly provided on the top side of the first flow slowdown shell, a partition is provided between the top side of the first flow slowdown shell and the second buffer shell, and a pressure equalizing hole is provided on the partition.

[0014] Through the above design, after the gas enters the first slow flow shell, a part of the gas will enter the second slow flow shell through the pressure equalizing hole on the partition plate provided on the top side of the first slow flow shell. The gas in the second slow flow shell is farther away from the air vent than the gas in the first slow flow shell, and the gas entering the second slow flow shell will be stored and buffered. When the air pressure of the external gas source fluctuates, the rubber plug in the first slow flow shell cooperates with the first spring to ensure the stability of the pressure in the first slow flow shell. At the same time, since the second slow flow shell only has a uniform hole connected to the first slow flow shell, it can achieve gas pressure stability when the gas pressure in the first slow flow shell changes and causes the gas flow in the second slow flow shell; when the external gas source is cut off, the gas in the first slow flow shell will flow out first, and then the gas in the second slow flow shell will be discharged into the diversion component. In this process, when the air floating platform is pressed down by gravity and pressure is generated on the magnetic preload air floating bearing, the pressure can be buffered by the first and second slow flow shells, and the gas buffering inside them is used, which actually plays an effect similar to that of an air spring.

[0015] According to one embodiment of the present invention, the diversion assembly includes an annular filter sleeve, a first base ring is coaxially spaced apart on the outside of the annular filter sleeve, a plurality of first filter plates are radially extended around the annular filter sleeve, the first filter plates are inclined, and the first filter plates are used to connect the annular filter sleeve with the first base ring, a second base ring is coaxially spaced apart on the outside of the first base ring, and the first base ring and the second base ring are connected by multiple bearings; the middle parts of the first base ring and the second base ring are both provided with multiple partitions, the second base ring is fixed to the air flotation base, and the second base ring is circumferentially arranged corresponding to the inner side of the air flotation structure.

[0016] Through the above design, the gas enters the diversion component from the annular filter sleeve, and the gas will flow radially to the outside of the annular filter sleeve under the action of the annular filter sleeve. When the gas flows through the inclined first filter plate, the first filter plate will rotate under the action of the gas. The first filter plate will carry the annular filter sleeve and the first base ring to rotate during the rotation. At this time, the first filter plate will further expand the contact with the gas. In this process, the gas will be filtered and processed by the annular filter sleeve and the first filter plate together, so as to achieve the adsorption of particulate matter and impurities in the gas, realize the filtration and purification of the gas, and prevent the subsequent blockage of part of the flotation structure. At the same time It can prevent the interception of particulate matter in the air and reduce the impact of particulate matter on the surface of the flotation guide rail with the high-speed airflow, causing surface wear and reducing the surface roughness of the flotation guide rail; in addition, the first filter plate is used to drive the rotation of the first base ring to achieve outward swirling airflow. The swirling airflow formed in this way can improve the smoothness of airflow discharge and guide the airflow in the direction of the upper slow flow component to flow outward, avoiding the smoothness of the entire air transmission path, and the swirling airflow plays a role in gas dispersion and uses the swirling airflow to ensure the existence of an effective air film or pressure between the flotation base and the flotation guide rail.

[0017] Furthermore, the annular filter sleeve is arranged corresponding to the air inlet channel, wherein the air inlet channel and the annular filter sleeve are arranged to rotate.

[0018] Furthermore, the annular filter sleeve is arranged corresponding to the slow flow component, and the slow flow component is circumferentially provided with a plurality of bearings which cooperate with the annular filter sleeve to realize the rotation of the annular filter sleeve.

[0019] According to an embodiment of the present invention, a plurality of cavities are formed by partitioning the middle portions of the first base ring and the second base ring, and a second filter plate is provided in the cavities.

[0020] Through the above design, a second filter plate is provided in the cavity, which can filter the gas when the gas enters the flotation structure from the diversion component; at the same time, the second filter plate located on the first base ring can realize the rotation of the first base ring. During the rotation, the gas can be filtered over a larger range and the gas can be cut, so that small streams of gas can enter the flotation structure. The cutting treatment of the gas can improve the uniformity of the gas when it enters the flotation structure, that is, the uniformity of the gas pressure and the uniformity of the gas flow rate, improve the uniformity of the air film formed when the flotation structure receives the gas, prevent the occurrence of air hammer phenomenon, and prevent the damage of the flotation structure caused by uneven gas pressure.

[0021] The present invention provides a linear platform for cooperating with the above-mentioned magnetic preload air floating bearing. The linear platform includes a load-bearing platform and an air floating platform. The load-bearing platform includes multiple air floating guide rails. The air floating platform is arranged corresponding to the multiple air floating guide rails. Multiple magnetic preload air floating bearings are evenly arranged on the side of the air floating platform opposite to the air floating guide rails.

[0022] According to an embodiment of the present invention, a plurality of positioning holes are provided on the air bearing platform, and the positioning holes are equipped with assembly parts. The positioning holes realize the fixed connection of the magnetic preload air bearing to the air bearing platform through the assembly parts.

[0023] Through the above design, by evenly disposing a plurality of magnetic preloaded air bearings on one side of the air floating platform relative to the air floating guide rail, it is possible to generate air films at multiple positions, thereby improving the stability of the air floating platform. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic perspective view of a magnetic preloaded air bearing;

[0025] FIG2 is a schematic cross-sectional view of a portion of an air-floating substrate;

[0026] Figure 3 is a cross-sectional schematic diagram of a slow flow assembly;

[0027] FIG4 is a schematic diagram of the slow flow assembly from another angle;

[0028] Figure 5 is a schematic diagram of the coordination between the diversion component and the slow flow component;

[0029] FIG6 is a schematic cross-sectional view of a diversion assembly;

[0030] Figure 7 is a three-dimensional schematic diagram of a linear platform;

[0031] Figure 8 is a schematic diagram of the cooperation between the air bearing platform and the magnetic preload air bearing;

[0032] Figure 9 is a perspective schematic diagram of a preload assembly;

[0033] Figure 10 is a schematic diagram of the cooperation between the fixed sleeve and the sliding rod;

[0034] FIG11 is a schematic cross-sectional view of the fixed sleeve and the sliding rod.

[0035] Reference numerals: air flotation substrate 1, air flotation structure 11, air inlet channel 12, preload assembly 2, magnet 21, limiting column 211, third sliding groove 212, fixing rod 22, first frame 23, first sliding groove 231, fixing sleeve 232, sliding rod 233, rotating member 234, deceleration groove 235, indentation 236, ridge 237, second frame 24, limiting plate 241, second sliding groove 242, diverter assembly 3, annular filter sleeve 31, first base ring 32, second base ring 33, bearing 34, second filter plate 35, Slow flow assembly 4, first slow flow shell 41, air vent 411, fixed barrel 412, limiting ring 413, rubber plug 414, first spring 415, air vent 416, second slow flow shell 42, partition 43, pressure equalizing hole 44, air floating platform 5, positioning hole 51, assembly part 52, air floating guide rail 61. DETAILED DESCRIPTION

[0036] The technical solution of the present invention is further described in detail below with reference to the specific embodiments and the accompanying drawings:

[0037] Example 1:

[0038] As shown in Figures 1 to 6, the magnetic preload air-floating bearing includes an air-floating base 1, which is surrounded by a plurality of preload components 2. An annular air-floating structure 11 is extended and protruded from one side of the air-floating base 1, and an air inlet channel 12 is extended and extended from the other side of the air-floating base 1. A diverter component 3 is provided in the air-floating base 1, and the side of the diverter component 3 is arranged corresponding to the inner side of the air-floating structure 11, and the air inlet channel 12 is arranged corresponding to the diverter component 3; the preload component 2 is connected to the air-floating base 1 through a fixing rod 22.

[0039] The air floating structure 11 is made of porous throttling material.

[0040] Through the overall setting of the magnetic preloaded air-floating bearing, the external air source will enter the air-floating matrix 1 through the air inlet channel 12, and the gas transported in the air inlet channel 12 will enter the diversion component 3. The diversion component 3 is used to realize the gas diversion in two directions, one direction is toward the air-floating structure 11, and the other direction is toward the air-floating guide rail 61. The air-floating structure 11 adopts a porous throttling material. The porous throttling material has a solid matrix and pores that are interconnected. The gas will be throttled by the porous throttling material and flow into the space between the porous throttling material and the air-floating guide rail 61. A porous throttling material and the air-floating guide rail 61 form a throttling space. A layer of air film is formed, and the air film is used to achieve the suspension of the air flotation guide rail 61 and the porous throttling material; because the air flotation structure 11 is an annular structure provided on one side of the air flotation base 1, a groove can be provided on one side of the air flotation base 1, that is, the diverter component 3 in the groove can discharge the gas toward the air flotation guide rail 61, which can maintain the gas pressure and make the gas pressure have a certain elastic range. That is, when the pressure of the gas delivered by the external gas source fluctuates, the gas can be stored and released in the groove to achieve the pressure fluctuation of the gas in the groove. The pressure is stable and the formation and thickness of the air film are not affected, preventing the occurrence of air hammer. By setting the diverter component 3, multiple exhaust directions can also be formed, and it is helpful to discharge the gas and improve the fluency of the exhaust.

[0041] The air-floating base 1 is surrounded by a plurality of preload components 2, and the preload components 2 are provided with magnetic attraction. The preload components 2 are used to cooperate with the air-floating guide rail 61, that is, an adsorption strip or other magnetic attraction device compatible with the preload component 2 is provided opposite to the air-floating guide rail 61, so that the magnetic preload air-floating bearing may be unstable during its movement, such as the air-floating bearing shaking, tilting, etc. The preload components 2 arranged around the air-floating base 1 form a force between the air-floating guide rail 61 through magnetic attraction, so as to assist in improving the stability of the magnetic preload air-floating bearing during operation by magnetic attraction; when the external air source stops supplying air, the setting of the preload component 2 can quickly adsorb with the air-floating guide rail 61 to stop the air-floating platform 5 from moving, reduce or avoid movement errors, and improve the braking reaction efficiency and speed.

[0042] A slow flow component 4 is provided at the end of the air intake channel 12, and the slow flow component 4 is arranged in cooperation with the diversion component 3. The slow flow component 4 includes a first slow flow shell 41, and the end of the air intake channel 12 is arranged through the top of the first slow flow shell 41, and the first slow flow shell 41 is laterally surrounded by air holes 411; a fixed barrel 412 is coaxially provided in the first slow flow shell 41, and an air hole 416 is provided on the side of the fixed barrel 412. The bottom side of the fixed barrel 412 is arranged corresponding to the bottom side of the first slow flow shell 41, and a limiting ring 413 is extended to the opposite side of the bottom side of the fixed barrel 412 and the bottom side of the first slow flow shell 41. A rubber plug 414 that can slide axially along the first slow flow shell 41 is provided on the opposite side of the fixed barrel 412 and the first slow flow shell 41. A first spring 415 is provided on one side of the rubber plug 414, and the other side of the first spring 415 is connected to the top side of the first slow flow shell 41.

[0043] Through the above design, after the gas enters the first slow-flow housing 41 from the air inlet channel 12, it is temporarily stored in the first slow-flow housing 41 and then discharged from the air vent 411 into the diverter assembly 3. The slow-flow assembly 4 is used to provide a buffer for the gas after entering the air flotation base 1. Because a rubber plug 414 and a first spring 415 are provided in the first slow-flow housing 41, wherein the rubber plug 414 can slide and move axially along the first slow-flow housing 41, the rubber plug 414 and the first spring 415 can cooperate to control the airflow space inside the first slow-flow housing 41, thereby controlling the air pressure inside the first slow-flow housing 41 and the air pressure of the gas discharged from the air vent 411, thereby avoiding the situation where the air pressure value is lost during the long air pipe transportation process. The top side of the slow-flow assembly 4 is connected to a connecting base member, which is used to be fixedly connected to the air flotation base 1.

[0044] A second flow-slowing shell 42 is correspondingly provided on the top side of the first flow-slowing shell 41 . A partition 43 is provided between the top side of the first flow-slowing shell 41 and the second flow-slowing shell. A pressure-equalizing hole 44 is provided on the partition 43 .

[0045] Through the above design, after the gas enters the first slow-flow shell 41, a part of the gas will enter the second slow-flow shell 42 through the pressure-equalizing hole 44 on the partition 43 set on the top side of the first slow-flow shell 41. The gas in the second slow-flow shell 42 is farther away from the air vent 411 than the gas in the first slow-flow shell 41, and the gas entering the second slow-flow shell 42 will be stored and buffered. When the air pressure of the external air source fluctuates, the rubber plug 414 in the first slow-flow shell 41 cooperates with the first spring 415 to ensure the stability of the pressure in the first slow-flow shell 41. At the same time, the second slow-flow shell 42 is Since it only has a uniform hole connected to the first slow-flow shell 41, it can achieve gas pressure stabilization when the change of gas pressure in the first slow-flow shell 41 causes gas flow in the second slow-flow shell 42; when the external gas source is cut off, the gas in the first slow-flow shell 41 will flow out first, and then the gas in the second slow-flow shell 42 will be discharged into the diversion component 3. In this process, when the air-floating platform 5 is pressed down by gravity and pressure is generated on the magnetic preload air-floating bearing, the pressure can be buffered by the first and second slow-flow shells 42, and the gas inside them is used for buffering, which actually plays an effect similar to that of an air spring.

[0046] The diversion assembly 3 includes an annular filter sleeve 31, and a first base ring 32 is coaxially spaced apart on the outside of the annular filter sleeve 31. A plurality of first filter plates are radially extended around the annular filter sleeve 31, and the first filter plates are tilted. The first filter plates are used to connect the annular filter sleeve 31 with the first base ring 32. A second base ring 33 is coaxially spaced apart on the outside of the first base ring 32, and the first base ring 32 and the second base ring 33 are connected by a plurality of bearings 34; the middle parts of the first base ring 32 and the second base ring 33 are both provided with multiple partitions, the second base ring 33 is fixed to the air flotation substrate 1, and the second base ring 33 is circumferentially arranged corresponding to the inner side of the air flotation structure 11.

[0047] Through the above design, the gas enters the diversion component 3 from the annular filter sleeve 31, and the gas will flow radially to the outside of the annular filter sleeve 31 under the action of the annular filter sleeve 31. When the gas flows through the inclined first filter plate, the first filter plate will rotate under the action of the gas. During the rotation, the first filter plate will carry the annular filter sleeve 31 and the first base ring 32 to rotate. At this time, the first filter plate will further expand the contact with the gas. In this process, the gas will be filtered and processed by the annular filter sleeve 31 and the first filter plate together, so as to achieve the adsorption of particulate matter and impurities in the gas, realize the filtration and purification of the gas, and prevent the subsequent blockage of part of the flotation structure 11 At the same time, it can prevent the interception of particulate matter in the air and reduce the impact of particulate matter on the surface of the flotation guide rail 61 with the high-speed airflow, causing surface wear and resulting in the problem of reduced surface roughness of the flotation guide rail 61; in addition, the first filter plate is used to drive the rotation of the first base ring 32, so as to realize the outward swirling airflow. The swirling airflow formed in this way can improve the smoothness of airflow discharge and guide the airflow in the direction of the upper slow flow component 4 to flow outward, avoiding the unsmoothness of the entire air transmission path, and the swirling airflow plays a role in gas dispersion and utilizes the swirling airflow to ensure the existence of an effective air film or pressure between the flotation base 1 and the flotation guide rail 61.

[0048] Furthermore, the annular filter sleeve 31 is arranged corresponding to the air inlet channel 12. The air inlet channel 12 and the annular filter sleeve 31 are arranged to rotate.

[0049] Furthermore, the annular filter sleeve 31 is provided corresponding to the slow flow component 4 , and the slow flow component 4 is provided with a plurality of bearings 34 in the circumference thereof. Due to the cooperation with the annular filter sleeve 31 , the annular filter sleeve 31 is used to realize the rotation of the annular filter sleeve 31 .

[0050] The middle parts of the first base ring 32 and the second base ring 33 are separated to form a plurality of cavities, and the second filter plates 35 are arranged in the cavities.

[0051] Through the above design, a second filter plate 35 is provided in the cavity, which can filter the gas when the gas enters the flotation structure 11 from the diversion component 3; at the same time, the second filter plate 35 located on the first base ring 32 can realize the rotation of the first base ring 32. During the rotation, the gas can be filtered in a larger range and the gas can be cut, so that small streams of gas can enter the flotation structure 11. The cutting treatment of the gas can improve the uniformity of the gas when it enters the flotation structure 11, that is, the uniformity of the gas pressure and the uniformity of the gas flow rate, improve the uniformity of the air film formed when the flotation structure 11 receives the gas, prevent the occurrence of air hammer phenomenon, and prevent the damage of the flotation structure 11 caused by uneven gas pressure.

[0052] Example 2:

[0053] As shown in Figures 7 and 8, a linear platform according to an embodiment of the present invention is shown, which is used to cooperate with the above-mentioned magnetic preload air bearing. The linear platform includes a load-bearing platform and an air bearing platform 5. The load-bearing platform includes multiple air bearing guide rails 61. The air bearing platform 5 is arranged corresponding to the multiple air bearing guide rails 61. Multiple magnetic preload air bearings are evenly arranged on the side of the air bearing platform 5 opposite to the air bearing guide rails 61.

[0054] The air-floating platform 5 is provided with a plurality of positioning holes 51 , and the positioning holes 51 are matched with assembly parts 52 . The positioning holes 51 are fixedly connected to the air-floating platform 5 through the assembly parts 52 .

[0055] The above design, by evenly distributing multiple magnetic preloaded air bearings on the side of the air flotation platform 5 opposite the air flotation guide rail 61, allows for the generation of air films at multiple locations, thereby improving the stability of the air flotation platform 5. Furthermore, the multiple air flotation guide rails 61 are provided with adsorption strips corresponding to the magnetic preloaded air flotation bearings, and the adsorption strips are configured to cooperate with the magnetic preloaded air flotation bearings. Furthermore, the multiple air flotation guide rails 61 are magnetic.

[0056] Furthermore, the assembly part 52 may be connected to an air pipe, through which air may be supplied to the magnetic preload air bearing.

[0057] Example 3:

[0058] As shown in Figures 9 to 11, a magnetic preload air bearing according to another embodiment of the present invention is different from Example 1 in that the preload assembly 2 includes a magnet 21, a first frame 23 and a second frame 24. The magnet 21 is accommodated in the second frame 24, and the second frame 24 is accommodated in the first frame 23. The plane of the first frame 23 is perpendicular to the plane of the second frame 24. A first sliding groove 231 is provided on the opposite side of one side of the first frame 23. The first sliding groove 231 is slidably matched with a fixed sleeve 232. A sliding rod 233 is provided through the fixing sleeve 232, and one end of the sliding rod 233 is connected to the magnet 21; limiting plates 241 are provided on both sides of the second frame 24, and second sliding grooves 242 are provided on the other opposite sides of the first frame 23. The second sliding grooves 242 are matched with the limiting plates 241, and limiting columns 211 are provided on both sides of the magnet 21. The second sliding groove is provided with third sliding grooves 212 on both sides relative to the magnet 21. The third sliding grooves 212 are matched with the limiting columns 211, and the fixing rod 22 is connected to the first frame 23.

[0059] Through the above design, the magnet 21 can be made to slide relative to the first frame 23 and the second frame 24. That is, by setting the magnet 21 to slide, the distance between the magnet 21 and the air-floating substrate 1 can be controlled, and the magnetic adsorption range can be automatically adjusted according to the flow rate / pressure of the gas discharged from the air-floating substrate 1. The setting of the first frame 23 and the second frame 24 helps to protect the periphery of the air-floating substrate 1. When the air-floating substrate 1 moves downward due to the gravity of the air-floating platform 5 and the preload assembly 2 is adsorbed to the load-bearing platform due to the suction force of the magnet 21, the second frame 24 now comes into contact with the air-floating guide rail 61, preventing the air-floating substrate 1 of the air-floating bearing from contacting the surface of the air-floating guide rail 61, thereby protecting the air-floating substrate 1. It should be noted that the first frame 23 and the second frame 24 are made of rubber to avoid friction damage caused by contact with the air-floating guide rail 61.

[0060] In addition, the preload component 2 can also control the range of strong airflow discharged outward / around the air-floating base 1 to be within the range where the preload component 2 is arranged around the air-floating base 1, that is, the airflow pressure in the circular area around the air-floating base 1 where the preload component 2 is arranged is stronger, because the preload component 2 on the periphery interferes with the external exhaust flow, and the airflow pressure outside this area is relatively low. The purpose of this is to ensure that the airflow pressure or air film pressure of the air-floating base 1 relative to the surface of the air-floating guide rail 61, or to ensure that the distance between the two is within a stable range value.

[0061] Rotating parts 234 are provided on the connecting rod opposite to each other. The two rotating parts 234 are respectively provided on both sides of the fixed sleeve 232. The opposite sides of the rotating parts 234 are inclined. A plurality of indentations 236 are circumferentially provided on the opposite sides of the rotating parts 234. Speed ​​reduction grooves 235 are provided at both ends of the fixed sleeve 232. The speed reduction grooves 235 are provided corresponding to the rotating parts 234. The speed reduction grooves 235 and the rotating parts 234 are provided on the opposite sides thereof with convex strips 237 which are matched with the indentations 236.

[0062] Through the above design, when the rotating member 234 is not in contact with the fixed sleeve 232, the connecting rod can move relative to the fixed sleeve 232, so that the magnet 21 connected to the connecting rod can move freely along the axial direction of the connecting rod; when the rotating member 234 is in contact with the fixed sleeve 232, the indentation 236 of the rotating member 234 will cooperate with the ridge 237 of the deceleration groove 235, thereby organizing the movement of the rotating member 234 and limiting the sliding distance of the magnet 21. By controlling the sliding distance, the accuracy of the preload assembly 2 can be improved, and the inertia force of the magnet 21 can be absorbed by utilizing the contact between the rotating member 234 and the fixed sleeve 232.

[0063] The embodiments described above provide a detailed description of the technical solutions of 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, supplements or similar substitutions made within the scope of the principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A magnetic preloaded air bearing, comprising an air-floating substrate (1), wherein the air-floating substrate (1) is surrounded by a plurality of preload components (2), characterized in that: An annular air-floating structure (11) is extended and protruded from one side of the air-floating substrate (1), an air inlet channel (12) is extended and penetrated from the other side of the air-floating substrate (1), a flow diversion component (3) is arranged inside the air-floating substrate (1), the side of the flow diversion component (3) is arranged correspondingly to the inner side of the air-floating structure (11), the air inlet channel (12) is arranged correspondingly to the flow diversion component (3), a slow-flow component (4) is arranged at the end of the air inlet channel (12), and the slow-flow component (4) is arranged in coordination with the flow diversion component (3); The flow splitter assembly (3) comprises an annular filter sleeve (31), a first base ring (32) is coaxially spaced outside the annular filter sleeve (31), a second base ring (33) is coaxially spaced outside the first base ring (32), the second base ring (33) is fixedly arranged on the air-floating substrate (1), and the second base ring (33) is circumferentially arranged corresponding to the inner side of the air-floating structure (11); The preload assembly (2) is connected to the air-floating base (1) via a fixing rod (22); The preload assembly (2) comprises a magnet (21), a first frame (23) and a second frame (24); the magnet (21) is accommodated in the second frame (24); the second frame (24) is accommodated in the first frame (23); the plane of the first frame (23) and the plane of the second frame (24) are perpendicular to each other; a first sliding groove (231) is provided on the opposite side of one side of the first frame (23); a fixing sleeve (232) is slidably provided in the first sliding groove (231); a sliding rod (233) is provided through the fixing sleeve (232); and one end of the sliding rod (233) is connected to the magnet (21); The second frame (24) is provided with a limiting plate (241) on both sides, the first frame (23) is provided with a second sliding groove (242) on the other opposite sides, the second sliding groove (242) and the limiting plate (241) are arranged in cooperation, limiting columns (211) are provided on both sides of the magnet (21), the second sliding groove is provided with a third sliding groove (212) on both sides relative to the magnet (21), the third sliding groove (212) and the limiting column (211) are arranged in cooperation, and the fixing rod (22) is connected to the first frame (23).

2. The magnetic preload air bearing according to claim 1, characterized in that: The slow-flow assembly (4) comprises a first slow-flow housing (41), the end of the air inlet passage (12) is arranged through the top of the first slow-flow housing (41), and air holes (411) are arranged laterally around the first slow-flow housing (41); A fixed barrel (412) is coaxially arranged inside the first slow-flow shell (41), a vent hole (416) is arranged on the side of the fixed barrel (412), the bottom side of the fixed barrel (412) is arranged corresponding to the bottom side of the first slow-flow shell (41), a limiting ring (413) is extended from the bottom side of the fixed barrel (412) and the side opposite to the bottom side of the first slow-flow shell (41), a rubber plug (414) that slides axially along the first slow-flow shell (41) is arranged on the side opposite to the first slow-flow shell (41), a first spring (415) is arranged on one side of the rubber plug (414), and the other side of the first spring (415) is connected to the top side of the first slow-flow shell (41).

3. The magnetic preload air bearing according to claim 2, characterized in that: A second flow-slowing shell (42) is correspondingly provided on the top side of the first flow-slowing shell (41), a partition plate (43) is provided between the top side of the first flow-slowing shell (41) and the second flow-slowing shell, and a pressure-equalizing hole (44) is provided on the partition plate (43).

4. The magnetic preload air bearing according to claim 1, characterized in that: The annular filter sleeve (31) is provided with a plurality of first filter plates extending radially therearound, the first filter plates being arranged obliquely, the first filter plates being used to realize the connection between the annular filter sleeve (31) and the first base ring (32), and the first base ring (32) and the second base ring (33) being connected via a plurality of bearings (34); The first base ring (32) and the second base ring (33) are both provided with a plurality of partitions in the middle.

5. The magnetic preload air bearing according to claim 4, characterized in that: The first base ring (32) and the second base ring (33) are separated in the middle to form a plurality of cavities, and a second filter plate (35) is arranged in the cavities.

6. The magnetic preloaded air bearing according to claim 1, characterized in that: The air floating structure (11) adopts porous throttling material.

7. A linear stage having a magnetic preloaded air bearing as claimed in any one of claims 1 to 6, characterized in that: The linear platform comprises a load-bearing platform and an air-floating platform (5), the load-bearing platform comprises a plurality of air-floating guide rails (61), the air-floating platform (5) is arranged corresponding to the plurality of air-floating guide rails (61), and a plurality of magnetic preloaded air-floating bearings are evenly arranged on one side of the air-floating platform (5) opposite to the air-floating guide rails (61).

8. The linear platform according to claim 7, characterized in that: The air-floating platform (5) is provided with a plurality of positioning holes (51), and the positioning holes (51) are matched with assembly parts (52). The positioning holes (51) are used to fix the magnetic preload air-floating bearing on the air-floating platform (5) through the assembly parts (52).

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