Aerostatic bearing and air main shaft with same

Abstract

A sleeve body is provided with a middle cavity, the side wall of the sleeve body is provided with an air inlet channel communicated with the middle cavity, limiting grooves communicated with the middle cavity are formed in the two opposite ends of the sleeve body and located on the sides of the middle cavity respectively, and a core body is provided with an inner cavity. The core body comprises a limiting ring and an extension ring which is arranged on the limiting ring and is provided with a through hole structure, the limiting ring is embedded into the limiting groove, the extension ring extends into the middle cavity, the two extension rings in the pair of core bodies abut against each other, and the positioning ring is provided with a receding cavity, is screwed in the limiting groove and abuts against the limiting ring. The pair of core bodies are fixed on the sleeve body, the relatively independent core bodies can be independently repaired, maintained and replaced, the treatment efficiency can be improved, the use cost can be reduced, and the pair of core bodies are of a symmetrical structure, so that the matching between the core bodies is facilitated, and the disassembly and assembly are convenient.

Description

Technical Field

[0001] This utility model relates to the technical field of bearing devices for air spindles, and more particularly to air hydrostatic bearings and air spindles having the same. Background Technology

[0002] An air spindle is a high-precision rotary device characterized by high-speed rotation, precise control, and low inertia, suitable for high-precision and high-speed machining applications. The main structure of an air spindle includes a housing, spindle, stator, and air hydrostatic bearings. The air hydrostatic bearings utilize gas as a lubricating medium to create an air film between the bearing and the spindle, achieving contactless operation and thus improving the spindle's rotational accuracy.

[0003] In the prior art, such as the ultra-precision hydrostatic gas bearing device with application number 201920015558.5, the device is an integral structure or the throttle assembly with air holes is an integral structure. However, when the air static bearing is used in an air spindle, if the rotating shaft and the air static bearing need to be repaired, maintained or replaced due to factors such as collision or temperature changes at the application site, the entire device needs to be handled, which leads to low processing efficiency or increased replacement and maintenance costs. Utility Model Content

[0004] The purpose of this utility model is to provide an air static pressure bearing and an air spindle having the same. A pair of cores are fixed on the sleeve. The relatively independent cores can be repaired, maintained and replaced separately, which can improve processing efficiency and reduce usage costs. The pair of cores have a symmetrical structure, which facilitates matching between the cores and makes disassembly and assembly convenient.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is: an air static pressure bearing, comprising:

[0006] The sleeve has a central cavity, and its side wall is provided with at least one air intake channel communicating with the central cavity. The opposite ends of the sleeve are respectively provided with limiting grooves communicating with the central cavity on the sides of the central cavity.

[0007] A pair of symmetrical cores are arranged on opposite sides of the sleeve body. Each core has an inner cavity and includes a limiting ring and an extension ring with a through hole structure disposed on the limiting ring. The limiting ring is embedded in the limiting groove, and the extension ring extends into the inner cavity. The two extension rings of the pair of cores abut against each other.

[0008] A pair of positioning rings, each positioning ring having a clearance cavity and being screwed into the limiting groove and abutting against the limiting ring.

[0009] As a further optimization, the air intake channel includes an air intake hole and an air intake passage connected to the air intake hole and disposed on the side wall of the central cavity, wherein the side wall of the extension ring abuts against the side wall of the central cavity.

[0010] As a further optimization, the air intake channel includes an air intake hole, and there is a gap with an annular structure between the sidewall of the extension ring and the sidewall of the central cavity.

[0011] As a further optimization, a first groove is provided at the connection position between the limiting ring and the extension ring. A filter screen is embedded in the first groove and extends into the first groove of another core. The inner and outer sides of the filter screen abut against the sidewalls of the extension ring and the central cavity, respectively. The use and installation of the filter screen can ensure the cleanliness of the gas and the stability of the filter screen.

[0012] As a further optimization, a second groove is provided on the side edge of the limiting ring near the extension ring. A sealing ring is provided in the second groove, and the sealing ring abuts against the limiting groove, which can realize convenient installation of the sealing ring and ensure the sealing effect of the core and the sleeve.

[0013] As a further optimization, the inner cavity and the relief cavity have the same diameter.

[0014] As a further optimization, the outer wall of the positioning ring is provided with a first thread, and the side wall of the limiting groove away from the central cavity is provided with a second thread that matches the first thread.

[0015] As a further optimization, the positioning ring is provided with an insertion port, which facilitates the use of tools to rotate the positioning ring.

[0016] As a further optimization, the core is made of copper or graphite.

[0017] This utility model also provides an air spindle, including the aforementioned air hydrostatic bearing.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] 1. A pair of cores are fixed on the sleeve. The relatively independent cores can be repaired, maintained and replaced separately without replacing the entire throttle assembly or the entire air static pressure bearing, which can improve processing efficiency and reduce operating costs.

[0020] 2. The pair of cores have a symmetrical structure, which facilitates matching between cores and does not have special requirements for assembly order, making assembly convenient;

[0021] 3. The use of graphite material for components such as the core provides impact resistance, temperature resistance, and corrosion resistance, which helps the rotating shaft maintain uniform high-speed rotation during operation, thereby improving its stability and processing quality. Attached Figure Description

[0022] Figure 1 This is a structural diagram of the air static pressure bearing in this utility model.

[0023] Figure 2 This is an exploded view of the air static pressure bearing in this utility model.

[0024] Figure 3 for Figure 2 Enlarged view of point A in the middle.

[0025] Figure 4 This is a structural diagram of one embodiment of the core of the air static pressure bearing of this utility model.

[0026] Figure 5 This is a structural diagram of another embodiment of the core of the air static pressure bearing of this utility model.

[0027] Figure 6 This is a cross-sectional view of the air spindle in this utility model. Detailed Implementation

[0028] The following are specific embodiments of the present invention, which are described in conjunction with the accompanying drawings. However, the present invention is not limited to these embodiments.

[0029] like Figures 1 to 3 As shown, an air static pressure bearing 1A includes a sleeve 10, a core 20, and a positioning ring 30. The sleeve 10 has a central cavity 101, and its side wall is provided with at least one air intake channel 102 communicating with the central cavity 101. The opposite ends of the sleeve 10 are respectively provided with limiting grooves 103 communicating with the central cavity 101 on the sides of the central cavity 101. A pair of cores 20 are symmetrically arranged on opposite sides of the sleeve 10. The core 20 has an inner cavity 200. The specific structure of the core 20 includes a limiting ring 21, and a positioning ring 30 disposed on the limiting ring 21 and having... The extension ring 22 with through hole structure, the limiting ring 21 and the extension ring 22 have the same inner diameter to form an inner cavity 200. The limiting ring 21 is embedded in the limiting groove 103 and abuts against the limiting groove 103. The extension ring 22 extends into the middle cavity 101. The ends of the two extension rings 22 in a pair of cores 10 that are away from their respective limiting rings 21 abut against each other. The positioning ring 30 has a relief cavity 300. Preferably, the relief cavity 300 has the same diameter as the inner cavity 200. The positioning ring 30 is screwed into the limiting groove 103 and abuts against the limiting ring 21 to fix the core 20 to the sleeve 10.

[0030] In this invention, gas enters the sleeve 10 through the inlet channel 102 and enters the inner cavity 200 through the through-hole structure on the core 20 to support the rotating shaft located in the inner cavity 200. This invention sets up two relatively independent cores 20 adjacent to the rotating shaft. Compared to the conventional integral structure of an air static bearing or its integrated throttle assembly, the two cores 20 increase the number of components. However, when the air static bearing needs repair, maintenance, or replacement due to factors such as collisions or temperature changes at the application site, the relatively independent cores 20 can be handled separately without requiring the replacement of the entire throttle assembly or the entire air static bearing. This improves processing efficiency and reduces operating costs. Furthermore, the symmetrical structure of the pair of cores 20 facilitates matching with the other core 20 even when one core 20 is replaced, and there are no special requirements regarding the assembly sequence, making assembly convenient.

[0031] For the assembly of the air static pressure bearing 1A, firstly, a core 20 is embedded into the central cavity 101 of the sleeve 10, so that the limiting ring 21 abuts against the limiting groove 103. Specifically, the lower end face of the limiting ring 21 abuts against the horizontal surface 1031 in the limiting groove 103, and the side wall of the limiting ring 21 is located at the smooth wall surface 1032 in the limiting groove 103. Then, the positioning ring 30 is screwed into the second thread 11 in the limiting groove 103 through its first thread 31. After being fixed by the positioning ring 30, it is pressed onto the limiting ring 21 to fix the core 20. The other core 20 is installed in the same way, so that the extension ring 22 of the other core 20 abuts against the extension ring 22 of the first core 20. In addition, to facilitate the rotation of the positioning ring 30, a socket 32 ​​can be provided on the positioning ring 30, and a tool can be inserted into the socket 32 ​​to drive it to rotate.

[0032] Furthermore, a groove can be provided on one of the limiting groove 103 and the limiting ring 21, and a protrusion can be provided on the other. For example, a groove can be provided on the vertical side wall of the limiting groove 103, and a protrusion can be provided on the vertical side wall of the limiting ring 21. The cooperation between the protrusion and the groove can ensure the stability of the limiting ring 21 (core 20) on the sleeve 10 and prevent it from rotating.

[0033] In this utility model, if the sleeve 10, core 20 and positioning ring 30 are made of graphite, especially the core 20 and positioning ring 30 adjacent to the rotating shaft are made of graphite, the impact resistance, temperature resistance and corrosion resistance of the air static pressure bearing and the rotating shaft can be improved. This is beneficial for the rotating shaft to maintain uniform high-speed rotation during operation, and can improve its stability and processing quality.

[0034] After a pair of cores 20 abut against each other, their respective extension rings 22 form a throttle assembly. The through-hole structure allows gas to pass through and enter the inner cavity 200. In one embodiment of this utility model, similar to the prior art, the air intake channel 102 includes an air intake hole provided on the sleeve 10 and an air intake channel connected to the air intake hole and provided on the side wall of the middle cavity 101. That is, multiple airflow grooves are opened on the side wall of the middle cavity 101. The airflow grooves are connected to the air intake hole and extend on the side wall of the middle cavity 101. The side wall of the extension ring 22 abuts against the side wall of the middle cavity 101. Gas enters from the air intake hole and enters the air intake channel. After being diffused through the air intake channel, it is discharged into the inner cavity 200 through the through-hole structure on the extension ring 22.

[0035] In another embodiment of this utility model, the air intake channel 102 includes only an air intake hole disposed on the sleeve 10 and connected to the middle cavity 101, and there is an annular gap between the side wall of the extension ring 22 and the side wall of the middle cavity 101. Gas enters from the air intake hole and enters the annular gap. After the gas diffuses in the gap, it is discharged into the inner cavity 200 through the through hole structure on the extension ring 22.

[0036] Preferably, in the above embodiments, at least two air intake channels 102 can be provided, and the two air intake channels 102 are symmetrically arranged on opposite sides of the sleeve 10, which is beneficial to ensure the balance of air intake volume and gas volume in the entire inner cavity 200.

[0037] like Figure 4 As shown, when there is a ring-shaped gap between the sidewall of the extension ring 22 and the sidewall of the cavity 101, a first groove 211 can be provided at the connection position of the limiting ring 21 and the extension ring 22. The filter screen 24 extending into the first groove 211 of another core 10 is embedded in the first groove 211. That is, the two ends of the filter screen 24 are positioned by a pair of first grooves 211 to ensure the stable installation of the filter screen 24. During the installation of the filter screen 24, one side of the filter screen 24 can be first sleeved on the extension ring 22 and inserted into the first groove 211. When installing the other core 20, its extension ring 22 is inserted into the filter screen 24 and finally the first groove 211 on the core 20 is sleeved on the other end of the filter screen 24 to complete the installation. The inner and outer sides of the filter screen 24 abut against the sidewalls of the extension ring 22 and the cavity 101, respectively, which can ensure the stability of the filter screen 24. The filter screen 24 is designed to allow air to enter and prevent dust from entering the core 20 or passing through the core 20 and entering the inner cavity 200, which would affect the operation of the rotating shaft or cause damage. The filter screen 24 is also relatively easy to install and remove. If it is to be removed for cleaning, only the positioning ring 30 on one side and the core 20 need to be removed.

[0038] like Figure 5 As shown, in another embodiment of this utility model, a second groove 212 is provided on the side edge of the limiting ring 21 near the extension ring 22. A sealing ring 23 is provided in the second groove 212, and the sealing ring 23 abuts against the limiting groove 103. Setting the second groove 212 at the side edge of the limiting ring 21 facilitates the installation of the sealing ring 23. The sealing ring 23 abuts against the horizontal surface 1031 and the smooth wall surface 1032 of the limiting groove 103, which can achieve the sealing effect between the core 20 and the sleeve 10. In addition, a sealing element can also be provided at the abutment position of the pair of extension rings 22.

[0039] like Figure 5 As shown, this utility model also provides an air spindle, including the aforementioned air static pressure bearing 1A, with a rotating shaft 1B passing through the inner cavity 200 of a pair of air static pressure bearings 1A, rotating at high speed through interaction with the stator 1C and driving the tool to rotate.

[0040] The specific embodiments described herein are merely illustrative examples illustrating the spirit of this utility model. Those skilled in the art to which this utility model pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of this utility model or exceeding the scope defined by the appended claims.

Claims

1. An air static pressure bearing, characterized in that, include: The sleeve has a central cavity, and its side wall is provided with at least one air intake channel communicating with the central cavity. The opposite ends of the sleeve are respectively provided with limiting grooves communicating with the central cavity on the sides of the central cavity. A pair of symmetrical cores are arranged on opposite sides of the sleeve body. Each core has an inner cavity and includes a limiting ring and an extension ring with a through hole structure disposed on the limiting ring. The limiting ring is embedded in the limiting groove, and the extension ring extends into the inner cavity. The two extension rings of the pair of cores abut against each other. A pair of positioning rings, each positioning ring having a clearance cavity and being screwed into the limiting groove and abutting against the limiting ring.

2. The air hydrostatic bearing according to claim 1, characterized in that, The air intake channel includes an air intake hole and an air intake passage connected to the air intake hole and disposed on the side wall of the central cavity, wherein the side wall of the extension ring abuts against the side wall of the central cavity.

3. The air hydrostatic bearing according to claim 1, characterized in that, The air intake channel includes an air intake hole, and there is a ring-shaped gap between the sidewall of the extension ring and the sidewall of the central cavity.

4. The air hydrostatic bearing according to claim 3, characterized in that, A first groove is provided at the connection position between the limiting ring and the extension ring, and a filter screen extending into a first groove of another core is embedded in the first groove; the inner and outer sides of the filter screen abut against the sidewalls of the extension ring and the cavity, respectively.

5. The air hydrostatic bearing according to any one of claims 1 to 4, characterized in that, The limiting ring has a second groove on the side edge near the extension ring, and a sealing ring is provided in the second groove, which abuts against the limiting groove.

6. The air hydrostatic bearing according to claim 1, characterized in that, The inner cavity and the relief cavity have the same diameter.

7. The air hydrostatic bearing according to claim 1, characterized in that, The outer wall of the positioning ring is provided with a first thread, and the side wall of the limiting groove away from the central cavity is provided with a second thread that matches the first thread.

8. The air hydrostatic bearing according to claim 7, characterized in that, The positioning ring is provided with an insertion port.

9. The air hydrostatic bearing according to claim 1, characterized in that, The core is made of copper or graphite.

10. An air spindle, characterized in that, Includes the air static bearing as described in any one of claims 1 to 9.

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