Air bearing, air suction head and machining method

Abstract

The invention belongs to the technical field of air bearings, and particularly relates to an air bearing, an air suction head and a machining method.The air bearing comprises a lining and a plurality of micropore pieces; the plurality of micropore pieces are provided with through micropore channels, and each micropore piece is fixedly arranged in the lining. According to the air bearing, the micropore piece with the micropore channel is fixed in the lining, so that the difficulty of machining the micropore channel on the lining does not need to be considered, and compared with an existing air bearing, the lining does not need to be divided into two parts to be machined, namely, an additional sealing groove does not need to be arranged, so that the machining efficiency of the whole air bearing can be improved, and the machining cost is reduced. And when the assembling environment of the whole air bearing is a certain value, the shaft body with the larger diameter can be supported, the diameter of the shaft body is increased, the contact area between the air floating working face and the shaft body can be increased, and therefore the air floating rigidity of the whole air bearing can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of air bearings, and in particular to an air bearing, an air bearing head and a processing method thereof. Background Art

[0002] Air bearings are a type of sliding bearing that uses compressed air as a lubricant. Due to their characteristics of no mechanical friction, low shear force, and low vibration, they are widely used in many fields. For example, in the field of semiconductor chip mounting technology, air bearings are often used in chip mounting air floating suction heads.

[0003] Specifically, see Figure 1 , the shaft 10 of the air-floating suction head is arranged in the air-floating hole of the air-floating bearing, and compressed air is transported into the air-floating hole through the micro-holes 210 on the air-floating bearing, so as to form an air-floating working surface in the air-floating hole for supporting the shaft 10. Since the micro-holes 210 are difficult to process, the air-floating bearing is often processed in two parts, that is, the air-floating bearing is divided into a shell 100 and a bushing 200. After the micro-holes 210 are processed on the bushing 200, the shell 100 is installed on the outside of the bushing 200, and then a sealing ring 400 is arranged between the shell 100 and the bushing 200 to seal the two, so as to ensure the stability of the compressed air transportation, thereby ensuring the stability of the air-floating bearing when working.

[0004] Before assembling the sealing ring 400, it is necessary to process the boss 300 for installing the sealing ring 400 on the bushing 200. The boss 300 is provided with a sealing groove adapted to the sealing ring 400. After the sealing ring 400 is installed in the sealing groove, the bushing 200 with the sealing ring 400 is completely inserted into the interior of the housing 100. During the assembly process of the bushing 200, it is necessary to prevent the sealing ring 400 from shifting, which makes the assembly difficult. In addition, the setting of the sealing groove increases the radial size of the bushing 200. When the assembly environment of the entire air bearing is a certain value, the size of the bushing 200 increases, which can only reduce the diameter of the shaft body 10, thereby failing to ensure the air bearing stiffness of the entire air bearing.

[0005] Therefore, the above problems need to be solved urgently. Summary of the invention

[0006] The object of the present invention is to provide an air bearing, an air suction head and a processing method, so as to improve the air bearing rigidity and the assembly efficiency of the air bearing.

[0007] To achieve this object, the present invention adopts the following technical solutions:

[0008] An air bearing, used for bearing a shaft, comprising:

[0009] A bushing having an air flotation hole adapted to the shaft body;

[0010] A plurality of microporous components, each having a microporous channel therethrough, each of the microporous components being fixedly placed in the bushing, and both ends of all the microporous channels being respectively connected to the air flotation holes and the air passages disposed inside the bushing;

[0011] Wherein, the inner wall of the air flotation hole has a continuous air flotation working surface, and the air flotation working surface covers the ends of all the microporous parts.

[0012] Preferably, the air passage comprises a main channel extending along the axial direction of the bushing and a plurality of radial branches communicating with the main channel, and each of the radial branches is correspondingly communicated with each of the microporous channels.

[0013] Preferably, the microporous member has a taper, and the microporous member is adapted to be snap-fitted with the radial branch.

[0014] Preferably, at least two rows of microporous components are provided at both ends of the bushing, and a plurality of microporous components are provided in each row and are evenly distributed along the circumference of the air flotation holes.

[0015] An air flotation suction head comprises a shaft body and the air flotation bearing as described above, wherein the shaft body is arranged in the air flotation hole.

[0016] A method for processing an air bearing, used for processing the above-mentioned air bearing, comprising:

[0017] The air passage communicating with the air flotation hole is provided inside the bushing;

[0018] The microporous member is provided with the microporous channel extending therethrough;

[0019] A plurality of microporous members with the microporous channels are fixedly placed in the airway, and both ends of all the microporous channels are respectively connected with the air flotation holes and the airway.

[0020] Preferably, holes are drilled on the outer peripheral wall of the bushing along the radial direction of the bushing to form radial branches for fixing the microporous member.

[0021] Preferably, the bushing is drilled along the axial direction of the bushing to form a main channel for connecting all the radial branches;

[0022] The opening of the main channel and / or the opening of the radial branch are selectively blocked by a plug.

[0023] Preferably, all the microporous components partially extend to the air flotation holes after being placed in the airway;

[0024] Cutting off the portions of all the microporous components extending to the air flotation holes;

[0025] The fracture of the microporous component is finely ground so that the fracture is contoured and flush with the inner wall of the air flotation hole.

[0026] Preferably, before installing the microporous component, glue is coated on the outer wall of the microporous component and / or the inner wall of the air passage.

[0027] Beneficial effects of the present invention:

[0028] The air-floating bearing, air-floating suction head and processing method proposed in the present invention fix the microporous part with microporous channels inside the bushing, so that there is no need to consider the difficulty of processing the microporous channels on the bushing, and compared with the existing air-floating bearing, there is no need to divide the bushing into two parts for processing, that is, there is no need to set an additional sealing groove, so the processing efficiency of the entire air-floating bearing can be improved, and when the assembly environment of the entire air-floating bearing is a certain value, it can support a shaft body with a larger diameter. The increase in the diameter of the shaft body can increase the contact area between the air-floating working surface and the shaft body, thereby improving the air-floating stiffness of the entire air-floating bearing. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a schematic diagram of the structure of an existing air bearing;

[0030] Figure 2 is a cross-sectional view of an air bearing and a shaft body in an embodiment of the present invention;

[0031] Figure 3 is a cross-sectional view of a bushing in an embodiment of the present invention;

[0032] Figure 4 2 is a cross-sectional view of a microporous member according to an embodiment of the present invention.

[0033] In the figure:

[0034] 100, housing; 200, bushing; 210, micropore; 300, boss; 400, sealing ring;

[0035] 10. Shaft body; 101. Vacuum suction hole;

[0036] 1. Bushing; 11. Air flotation hole; 12. Main channel; 13. Radial branch; 14. Vacuum hole;

[0037] 2. Microporous parts; 21. Microporous channels;

[0038] 3. Plug. DETAILED DESCRIPTION

[0039] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0040] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0041] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0042] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0043] See also Figures 2 to 4 In this embodiment, an air-floating bearing is proposed for supporting a shaft body 10, which includes a bushing 1 and a plurality of microporous parts 2. The bushing 1 has an air-floating hole 11 adapted to the shaft body 10; the plurality of microporous parts 2 have penetrating microporous channels 21, each microporous part 2 is fixedly placed in the bushing 1, and both ends of all microporous channels 21 are respectively connected to the air-floating hole 11 and the airway arranged inside the bushing 1; wherein the inner wall of the air-floating hole 11 has a continuous air-floating working surface, and the air-floating working surface covers the ends of all microporous parts 2.

[0044] It is understandable that the microporous member 2 with the microporous channel 21 is fixed inside the bushing 1, so there is no need to consider the difficulty of processing the microporous channel 21 on the bushing 1, and compared with the existing air-floating bearing, there is no need to divide the bushing 1 into two parts for processing, that is, there is no need to set an additional sealing groove, so the processing efficiency of the entire air-floating bearing can be improved, and when the assembly environment of the entire air-floating bearing is a certain value, it can support the shaft body 10 with a larger diameter, and the increase in the diameter of the shaft body 10 can increase the contact area between the air-floating working surface and the shaft body 10, thereby improving the air-floating stiffness of the entire air-floating bearing. And the continuous air-floating working surface can further ensure the contact area with the shaft body 10, and further ensure the air-floating stiffness of the air-floating bearing.

[0045] In actual applications, one end of the airway can be connected to an external air supply structure, and the other end is connected to the flotation hole 11. The air supply structure delivers compressed air into the airway, and the compressed air enters the interior of the flotation hole 11 through the microporous channel 21, and forms a continuous flotation working surface inside the flotation hole 11. Among them, the airway includes a main channel 12 extending along the axial direction of the bushing 1 and a plurality of radial branches 13 connected to the main channel 12, and each radial branch 13 is connected to each microporous channel 21. It can be understood that each microporous member 2 is correspondingly installed on a different radial branch 13, and each radial branch 13 is connected through the main channel 12. During the air supply process, the main channel 12 can be set in the air path as a pressure equalizing channel, so as to ensure that the air pressure of the compressed air delivered by each microporous channel 21 is consistent, thereby ensuring the stability of the flotation working surface.

[0046] In this embodiment, the microporous member 2 has a taper, and the microporous member 2 is adapted to be engaged with the radial branch 13. It is understandable that the microporous member 2 can be installed on the bushing 1 as a standard part, and different microporous members 2 are provided with microporous channels 21 of different models and / or different arrangements, so as to facilitate the installation and replacement of the microporous member 2.

[0047] Exemplarily, the microporous member 2 is shaped like a cone or a truncated cone, with a small end and a large end. During installation, the small end is set toward the air flotation hole 11, and then the microporous member 2 is inserted into the radial branch 13 to complete the clamping connection between the two.

[0048] Based on the above, this embodiment also provides an air bearing processing method for processing the air bearing, which includes the following steps:

[0049] Step 1: Open an air passage in the bushing 1 to communicate with the air flotation hole 11;

[0050] Step 2: Opening a penetrating microporous channel 21 on the microporous member 2;

[0051] Step 3: Place several microporous components 2 with microporous channels 21 into the airway in a fixed manner, and both ends of all microporous channels 21 are connected to the air flotation holes 11 and the airway respectively. Before assembling the microporous components 2, microporous channels 21 that penetrate the microporous components 2 need to be opened on the microporous components 2.

[0052] It can be understood that the microporous member 2 with the microporous channel 21 is fixed inside the bushing 1, so there is no need to consider the difficulty of processing the microporous channel 21 on the bushing 1, and compared with the existing air bearing, there is no need to divide the bushing 1 into two parts for processing, that is, there is no need to set an additional sealing groove, thereby improving the processing efficiency of the entire air bearing.

[0053] In step 1, holes are drilled on the outer peripheral wall of the bushing 1 along the radial direction of the bushing 1 to form radial branches 13 for fixing the microporous member 2. It can be understood that by drilling holes on the bushing 1, openings of the radial branches 13 can be formed on the outer surface of the bushing 1, and any opening of the radial branches 13 can be connected to the external air supply structure to supply air to the air path.

[0054] Furthermore, after the radial branches 13 are opened, the bushing 1 is drilled along the axial direction of the bushing 1 to form a main channel 12 for connecting all the radial branches 13;

[0055] Subsequently, the opening of the main channel 12 and / or the opening of the radial branch 13 are selectively blocked by the plug 3 .

[0056] It can be understood that the main channel 12 can be arranged in the air circuit as a pressure equalizing channel, so as to ensure that the air pressure of the compressed air delivered by each microporous channel 21 is consistent. Therefore, during the air supply process, it is only necessary to ensure that at least one of the openings is connected to the air supply structure to supply air to the main channel 12, and the remaining openings are closed by the plug 3, so as to ensure the sealing of the main channel 12.

[0057] In step three, after all the microporous parts 2 are placed in the airway, they are partially extended to the flotation holes 11, and then the parts of all the microporous parts 2 extending to the flotation holes 11 are cut off; with this arrangement, during the assembly process, there is no need to accurately locate the assembly position of the microporous parts 2, which can ensure the assembly quality of the microporous parts 2 and improve the assembly efficiency.

[0058] Furthermore, the fracture of the microporous member 2 is finely ground so that the fracture is contoured and flush with the inner wall of the air-floating hole 11. Such a configuration can ensure the continuity of the air-floating working surface, thereby further ensuring the air-floating rigidity of the air-floating bearing.

[0059] In step three, before installing the microporous member 2, glue is applied on the outer wall of the microporous member 2 and / or the inner wall of the air channel. It is understandable that before assembling the microporous member 2, glue can be applied on the outer periphery of the microporous member 2 or the inner periphery of the microporous channel 21 to facilitate fixing the microporous member 2 after snap-fitting, and the applied glue can eliminate the mechanical error between the microporous member 2 and the radial branch 13, thereby further ensuring the sealing of the air bearing, so as to further improve the stability of the air bearing working surface.

[0060] Based on the above, this embodiment also proposes an air-floating suction head for patch, including a motor, a shaft 10 and the above-mentioned air-floating bearing, the shaft 10 is arranged inside the air-floating hole 11, and both ends can extend to the outside of the air-floating hole 11, one end is provided with a vacuum suction hole 101, and the other end is connected to the motor, wherein one end of the vacuum suction hole 101 can be connected to the external vacuum pumping structure, and the other end is used to adsorb the semiconductor product. The motor is used to drive the shaft 10 to rotate. And under the action of the above-mentioned air-floating bearing, it can ensure the fast and high-precision radial rotation movement of the shaft 10, thereby improving the patch accuracy.

[0061] Exemplarily, the vacuum suction hole 101 is connected to the air flotation hole 11, and a vacuum hole 14 is provided on the outer wall of the bushing 1. One end of the vacuum hole 14 is connected to the air flotation hole 11, and the other end is connected to the external vacuum structure. When the semiconductor product is adsorbed, the vacuum suction hole 101 of the shaft body 10 is controlled to be close to the semiconductor product, and the semiconductor product can be adsorbed under the action of the vacuum structure.

[0062] Furthermore, a buffer structure is provided between the shaft 10 and the motor, so as to allow the shaft 10 to move axially, so as to avoid hard contact between the shaft 10 and the semiconductor product when the semiconductor product is adsorbed. The buffer structure is preferably a spring.

[0063] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. An air bearing for supporting a shaft (10), characterized in that: include: A bushing (1) having an air flotation hole (11) adapted to the shaft body (10); A plurality of microporous components (2) having microporous channels (21) therethrough, each of the microporous components (2) being fixedly placed in the bushing (1), and both ends of all the microporous channels (21) being respectively connected to the air flotation holes (11) and the air passages arranged inside the bushing (1); The inner wall of the air flotation hole (11) has a continuous air flotation working surface, and the air flotation working surface covers the ends of all the microporous components (2).

2. The air bearing according to claim 1, characterized in that: The air channel comprises a main channel (12) extending along the axial direction of the bushing (1) and a plurality of radial branches (13) connected to the main channel (12), and each of the radial branches (13) is correspondingly connected to each of the microporous channels (21).

3. The air bearing according to claim 2, characterized in that: The microporous member (2) has a taper, and the microporous member (2) is adapted to be snap-fitted with the radial branch (13).

4. The air bearing according to claim 1, characterized in that: At least two rows of microporous components (2) are provided at both ends of the bushing (1), and a plurality of microporous components (2) are provided in each row and are evenly distributed along the circumference of the air flotation holes (11).

5. An air flotation suction head, characterized in that: It comprises a shaft body (10) and an air bearing as claimed in any one of claims 1 to 4, wherein the shaft body (10) is arranged in the air bearing hole (11).

6. A method for processing an air bearing, used for processing an air bearing as claimed in any one of claims 1 to 4, characterized in that: include: The air passage communicating with the air flotation hole (11) is provided inside the bushing (1); The microporous member (2) is provided with a penetrating microporous channel (21); A plurality of microporous components (2) with the microporous channels (21) are fixedly placed in the airway, and both ends of all the microporous channels (21) are respectively connected to the air flotation holes (11) and the airway.

7. The air bearing processing method according to claim 6, characterized in that: Holes are drilled on the outer peripheral wall of the bushing (1) along the radial direction of the bushing (1) to form radial branches (13) for fixing the microporous element (2).

8. The air bearing processing method according to claim 7, characterized in that: Drilling the bushing (1) along the axial direction of the bushing (1) to form a main channel (12) for connecting all the radial branches (13); The opening of the main channel (12) and / or the opening of the radial branch (13) are selectively blocked by a plug (3).

9. The air bearing processing method according to claim 6, characterized in that: After being placed in the airway, all of the microporous components (2) partially extend to the air flotation holes (11); Cutting off the portions of all the microporous elements (2) extending to the air flotation holes (11); The fracture of the microporous member (2) is finely ground so that the fracture is contoured and flush with the inner wall of the air flotation hole (11).

10. The air bearing processing method according to claim 6, characterized in that: Before installing the microporous member (2), glue is applied to the outer wall of the microporous member (2) and / or the inner wall of the air passage.

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