Air floatation thrust bearing, electric spindle and machine tool
By designing a structure with a throttling slot and an air intake channel on the axial thrust surface in the air-bearing thrust bearing, the problems of insufficient stability and load-bearing capacity of the air-bearing bearing are solved, and the performance of the high-speed and high-precision electric spindle is improved.
Patent Information
- Application Number
- CN202520266213.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-18
- Publication Date
- 2025-12-05
- Estimated Expiration
- 2035-02-18
AI Technical Summary
Existing air-bearing spindles suffer from structural defects in their air bearings, resulting in insufficient stability, rigidity, and load-bearing capacity of the high-pressure air film, making it difficult to meet the requirements of high speed and high precision.
Design an air-bearing thrust bearing with an axial thrust surface having a throttling slot extending in the circumferential direction and a connected air intake channel. By compressing gas to form a high-pressure air film, the shaft core assembly is supported to achieve non-contact suspension in the axial direction. The throttling slot extends continuously in the circumferential direction to improve stability and stiffness.
It achieves better stability and stronger load-bearing capacity, and supports the shaft core assembly to achieve non-contact suspension in the axial direction, thus improving the overall performance of the air bearing.
Smart Images
Figure CN223635147U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model is used in the main shaft field, and particularly relates to a gas floating thrust bearing, an electric spindle and a machine tool. BACKGROUND
[0002] With the demand of economic development and technology soaring, more and more new technologies emerge in an endless stream, and the mechanical processing industry also emerges in an endless stream, and the technical innovation of the leading main shaft industry is very obvious. Due to the forming and machining of automobile optical molds and the increasing precision of high light industry, the electric spindle is forced to develop towards high speed and high precision. The traditional ball bearing electric spindle is limited by the bearing, and its speed and precision are difficult to further improve. Therefore, the high speed and high precision of the main shaft industry must be researched and developed on the gas floating spindle.
[0003] The gas floating bearing of the existing gas floating spindle generally adopts gas small hole throttling to generate a high pressure gas film bearing the shaft core. The gas small hole throttling is large in quantity and difficult to process. Meanwhile, due to the structural defects, the high pressure gas film formed has defects in stability, stiffness and bearing capacity. UTILITY MODEL CONTENT
[0004] The utility model discloses a gas floating thrust bearing, an electric spindle and a machine tool.
[0005] The utility model discloses the technical scheme adopted to solve its technical problems is:
[0006] Firstly, a gas floating thrust bearing is provided with an axial thrust surface, the axial thrust surface extends in a circular direction in a ring shape, the axial thrust surface of the gas floating thrust bearing is provided with a throttling gap for the ejection of thrust gas flow, the throttling gap extends in a circular direction, and the gas floating thrust bearing is provided with an air inlet channel communicated with the throttling gap.
[0007] In combination with the first aspect, in some implementation manners of the first aspect, the gas floating thrust bearing comprises a first thrust bearing ring-shaped part and a second thrust bearing ring-shaped part, the front end axial end faces of the first thrust bearing ring-shaped part and the second thrust bearing ring-shaped part are flush, the flush front end axial end faces of the first thrust bearing ring-shaped part and the second thrust bearing ring-shaped part jointly form the axial thrust surface, the first thrust bearing ring-shaped part and the second thrust bearing ring-shaped part are in clearance fit, and the throttling gap is formed between the first thrust bearing ring-shaped part and the second thrust bearing ring-shaped part.
[0008] With reference to the first aspect and the above implementation manners, in some implementation manners of the first aspect, the first thrust bearing ring member is provided with an outer circumferential surface, the second thrust bearing ring member is provided with an inner circumferential surface, the second thrust bearing ring member is sleeved on the first thrust bearing ring member, and the outer circumferential surface of the first thrust bearing ring member and the inner circumferential surface of the second thrust bearing ring member form the throttling gap.
[0009] With reference to the first aspect and the above implementation manners, in some implementation manners of the first aspect, the first thrust bearing ring member is provided with a radial flange abutting against the second thrust bearing ring member from the rear side in the axial direction.
[0010] With reference to the first aspect and the above implementation manners, in some implementation manners of the first aspect, the aerostatic thrust bearing is mounted on a bearing seat by a screw, the radial flange and the second thrust bearing ring member are provided with axial screw holes at corresponding positions, the axial screw hole of the radial flange is a through hole, the axial screw hole of the second thrust bearing ring member is a blind hole, the screw passes through the axial screw hole of the radial flange and is connected to the axial screw hole of the second thrust bearing ring member, and the first thrust bearing ring member and the second thrust bearing ring member are locked on the bearing seat, and the first thrust bearing ring member and the second thrust bearing ring member are integrally machined to form flush axial thrust surfaces.
[0011] With reference to the first aspect and the above implementation manners, in some implementation manners of the first aspect, a sealing ring is arranged between the radial flange and the second thrust bearing ring member.
[0012] With reference to the first aspect and the above implementation manners, in some implementation manners of the first aspect, the outer circumferential surface of the first thrust bearing ring member is provided with a first annular groove and a plurality of air inlet holes in communication with the first annular groove, the air inlet holes extend to a tail end surface of the first thrust bearing ring member, the tail end surface of the first thrust bearing ring member is provided with a second annular groove in communication with the air inlet holes, and the second annular groove, the air inlet holes and the first annular groove form the air inlet channel.
[0013] With reference to the first aspect and the above implementation manners, in some implementation manners of the first aspect, the first annular groove divides the outer circumferential surface of the first thrust bearing ring member into a first outer circumferential surface and a second outer circumferential surface in the axial direction, the first outer circumferential surface is closer to the axial thrust surface than the second outer circumferential surface, the inner circumferential surface of the second thrust bearing ring member is in clearance fit with the first outer circumferential surface, and the inner circumferential surface of the second thrust bearing ring member is in interference fit with the second outer circumferential surface.
[0014] The second aspect is an aerostatic thrust bearing according to any one of the implementation manners of the first aspect.
[0015] In a third aspect, a machine tool comprises the electric spindle of any implementation of the second aspect.
[0016] One of the above technical solutions has at least one of the following advantages or beneficial effects: In the technical solution of the utility model, the axial thrust surface of the air floating thrust bearing is provided with a throttle gap for the thrust gas to be sprayed, compressed gas can enter from the air inlet channel and overflow from the throttle gap, thereby forming a high-pressure gas film between the flying discs of the shaft core assembly matched with the air floating thrust bearing, supporting the shaft core assembly to realize non-contact suspension in the axial direction. Compared with the discrete distribution of small hole throttling, the throttle gap relies on its own continuous extension in the circumferential direction, so that the air floating thrust bearing has better stability and stiffness, and has stronger carrying capacity.
[0017] Additional aspects and advantages of the utility model will be partially given in the following description, some will become apparent from the following description, or be understood through the practice of the utility model. BRIEF DESCRIPTION OF DRAWINGS
[0018] The above and / or additional aspects and advantages of the utility model will become apparent and more readily understood from the following description of the embodiments, in conjunction with the accompanying drawings, in which:
[0019] Figure 1 is an embodiment of the front end surface of the air floating thrust bearing of the utility model;
[0020] Figure 2 is a cross-sectional schematic view of an embodiment of the air floating thrust bearing of the utility model;
[0021] Figure 3 is a first thrust bearing ring part structure schematic view of an embodiment of the air floating thrust bearing of the utility model;
[0022] Figure 4 is a second thrust bearing ring part structure schematic view of an embodiment of the air floating thrust bearing of the utility model;
[0023] Figure 5 is a schematic view of the air floating thrust bearing of the utility model installed in the machine body bearing seat structure;
[0024] Figure 6 is a schematic view of the electric spindle of the utility model installed in the structure. DETAILED DESCRIPTION
[0025] The detailed embodiments of the present application will be described in this section. The preferred embodiments of the present application are shown in the drawings, and the drawings serve to supplement the description in the text part of the specification, so that each technical feature and the overall technical scheme of the present application can be understood intuitively and visually by people. However, it cannot be understood as a limitation on the protection scope of the present application.
[0026] In the present application, if the directions (up, down, left, right, front and back) are described, it is only for the convenience of describing the technical scheme of the present application, and it is not intended or implied that the technical features indicated must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application.
[0027] In the present application, the meaning of "several" is one or more, the meaning of "multiple" is two or more, and "greater than", "less than", "more than" and the like are understood as not including the number; "above", "below", "within" and the like are understood as including the number. In the description of the present application, if "first" and "second" are described, they are only used for the purpose of distinguishing technical features, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features or implicitly indicating the sequence of indicated technical features.
[0028] In the present application, unless otherwise explicitly limited, the words "set", "install", "connect" and the like should be broadly understood, for example, they can be directly connected, or indirectly connected through an intermediate medium; can be fixedly connected, or can be detachably connected, or can be integrally formed; can be mechanically connected, or can be electrically connected or capable of communicating with each other; can be the communication or interaction relationship between two elements. The skilled in the art can reasonably determine the specific meaning of the above words in the present application in combination with the specific content of the technical scheme.
[0029] Among them, Figure 2 The reference direction coordinate system of the embodiment of the present application is given, and the embodiment of the present application is described below in combination with the directions shown in the drawings. Figure 1
[0030] Referring to 1, Figure 2 , Figure 6 The embodiment of the utility model provides a kind of air floatation thrust bearing 200, it can be used in the axial thrust of main shaft middle shaft core subassembly 100, air floatation thrust bearing 200 is generally used in pair, to support shaft core subassembly 100 from both sides in axial direction realizes contactless suspension, air floatation thrust bearing 200 is equipped with axial thrust surface 201, axial thrust surface 201 is annular along circumferential direction and extends, the axial thrust surface 201 of air floatation thrust bearing 200 is equipped with throttle slit 202 for thrust airflow to spray, throttle slit 202 extends along circumferential direction, air floatation thrust bearing 200 is equipped with the air inlet channel that communicates with throttle slit 202.
[0031] In combination Figure 2 、 Figure 5 、 Figure 6 In the embodiment of the utility model, the axial thrust surface 201 of air floatation thrust bearing 200 is equipped with throttle slit 202 for thrust airflow to spray, compressed gas can enter from air inlet channel, overflow from throttle slit 202, to form high-pressure gas film between flying disc 101 of the shaft core subassembly 100 cooperating with air floatation thrust bearing 200, support shaft core subassembly 100 realizes contactless suspension in axial direction. By the throttle slit 202 of axial thrust surface 201 for thrust airflow to spray, compared with the small hole throttling of discrete distribution, throttle slit 202 relies on its own continuous extension along circumferential direction, so that air floatation thrust bearing 200 has better stability and rigidity, and the carrying capacity is stronger.
[0032] Air floatation thrust bearing 200 can be integrated, i.e. throttle slit 202 is provided on the axial thrust surface 201 of air floatation thrust bearing 200 by cutting, 3D printing or the like.
[0033] Air floatation thrust bearing 200 can also be assembled, in some embodiments, referring to Figure 2 、 Figure 3 、 Figure 4 Air floatation thrust bearing 200 includes first thrust bearing annular part 203 and second thrust bearing annular part 204, the front end axial end face of first thrust bearing annular part 203 and second thrust bearing annular part 204 is flush, the flush front end axial end face of first thrust bearing annular part 203 and second thrust bearing annular part 204 forms axial thrust surface 201, first thrust bearing annular part 203 and second thrust bearing annular part 204 are clearance fit, and throttle slit 202 is formed between first thrust bearing annular part 203 and second thrust bearing annular part 204. In the embodiment, the throttle slit 202 for thrust airflow to spray is formed by the cooperation gap between first thrust bearing annular part 203 and second thrust bearing annular part 204, the structure is simpler, and axial damping hole does not have to be provided on air floatation thrust bearing 200, and throttle slit 202 can continuously extend along the circumference, and better high-pressure gas film can be obtained.
[0034] The throttle gap 202 can extend in a circular or wavy shape in the circumferential direction. In some embodiments, referring to Figures 1-4 The first thrust bearing ring member 203 is provided with an outer circumferential surface 205, and the second thrust bearing ring member 204 is provided with an inner circumferential surface 206. The second thrust bearing ring member 204 is sleeved on the first thrust bearing ring member 203, and the outer circumferential surface 205 of the first thrust bearing ring member 203 is coaxial with the inner circumferential surface 206 of the second thrust bearing ring member 204, so that the throttle gap 202 with better uniformity can be easily obtained, and the air floating thrust bearing 200 has uniform axial gas film stiffness in the circumferential direction.
[0035] In some embodiments, referring to Figures 2-4 The first thrust bearing ring member 203 is provided with a radial flange 207 abutting against the second thrust bearing ring member 204 in the axial direction from the rear side. The first thrust bearing ring member 203 forms a groove space 208 in front of the radial flange 207, and the second thrust bearing ring member 204 can be installed in the groove space 208 to achieve accurate positioning and stable installation in the axial and radial directions.
[0036] Further, referring to Figures 2-5 The air floating thrust bearing 200 is installed on the bearing seat 400 through the screw 300. The radial flange 207 and the second thrust bearing ring member 204 are provided with axial screw holes at corresponding positions. The axial screw hole 209 of the radial flange 207 is a through hole, and the axial screw hole 210 of the second thrust bearing ring member 204 is a blind hole. The screw passes through the axial screw hole 209 of the radial flange 207 and is connected to the axial screw hole 210 of the second thrust bearing ring member 204, and locks the first thrust bearing ring member 203 and the second thrust bearing ring member 204 on the bearing seat 400. The first thrust bearing ring member 203 and the second thrust bearing ring member 204 are integrally machined to form flush axial thrust surfaces 201. In this embodiment, the first thrust bearing ring member 203 and the second thrust bearing ring member 204 are integrally machined after assembly, which can effectively improve the shape and position tolerances of the bearing in the radial and axial directions, and improve the precision and stability of the air floating bearing.
[0037] In some embodiments, referring to Figure 2 A sealing ring 211 is arranged between the radial flange 207 and the second thrust bearing ring member 204. The sealing ring 211 blocks the airflow to prevent the airflow in the air inlet channel from leaking through the gap between the second thrust bearing ring member 204 and the radial flange 207.
[0038] In some embodiments, referring toFigure 2 、 Figure 3 The outer circumferential surface 205 of the first thrust bearing annular part 203 is provided with a first ring groove 212 and a plurality of air inlet holes 213 in communication with the first ring groove 212, the air inlet holes 213 extending to the tail end surface of the first thrust bearing annular part 203, and the tail end surface of the first thrust bearing annular part 203 is provided with a second ring groove 214 in communication with the air inlet holes 213, the second ring groove 214, the air inlet holes 213 and the first ring groove 212 forming an air inlet channel. The air inlet channel of the embodiment can sufficiently ensure the uniformity of the air flow overflowing from the throttle gap 202.
[0039] In combination Figure 6 The high-pressure air from the bearing air inlet passes through the body assembly, enters the second ring groove 214 of the first thrust bearing annular part 203 in the upper air floating thrust bearing and the lower air floating thrust bearing respectively, then enters the first ring groove 212 through the air inlet holes 213, and is uniformly distributed along the first ring groove 212 and then overflows from the throttle gap 202, so that a high-pressure air film is formed between the upper and lower positions of the flying disc 101 of the shaft core assembly 100 and the upper air floating thrust bearing and the lower air floating thrust bearing. The high-pressure air film existing between the two supports the shaft core assembly 100 to realize non-contact suspension in the axial direction, and ensures that the shaft core assembly 100 has a certain carrying capacity and rigidity in the axial direction.
[0040] Further, referring to Figure 2 、 Figure 3 The first ring groove 212 divides the outer circumferential surface 205 of the first thrust bearing annular part 203 into a first outer circumferential surface 215 and a second outer circumferential surface 216 in the axial direction, the first outer circumferential surface 215 is closer to the axial thrust surface 201 than the second outer circumferential surface 216, the inner circumferential surface 206 of the second thrust bearing annular part 204 is in clearance fit with the first outer circumferential surface 215, and the inner circumferential surface 206 of the second thrust bearing annular part 204 is in interference fit with the second outer circumferential surface 216. The interference fit between the first thrust bearing annular part 203 and the second thrust bearing annular part 204 is adopted at the second outer circumferential surface 216, so as to further ensure the uniformity of the throttle gap 202 at the first outer circumferential surface 215 between the first thrust bearing annular part 203 and the second thrust bearing annular part 204.
[0041] The embodiment of the utility model further provides an electric spindle, which comprises the air floating thrust bearing 200 in any one of the above embodiments.
[0042] The embodiment of the utility model further provides a machine tool, which comprises the electric spindle in any one of the above embodiments.
[0043] In the description of the present specification, the description referring to the terms "example", "embodiment" or "some embodiments" or the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.
[0044] Of course, the present application is not limited to the above-described embodiments, and those skilled in the art can make equivalent modifications or substitutions without departing from the spirit of the present application, and these equivalent modifications or substitutions are included in the scope defined by the claims of the present application.
Claims
1. An air floating thrust bearing, characterized by The gas floating thrust bearing is provided with an axial thrust surface extending annularly in the circumferential direction, the axial thrust surface of the gas floating thrust bearing is provided with a throttle gap for the thrust gas flow to be sprayed, the throttle gap extends in the circumferential direction, and the gas floating thrust bearing is provided with an air inlet channel communicated with the throttle gap.
2. The air float thrust bearing of claim 1, wherein, The gas floating thrust bearing comprises a first thrust bearing annular part and a second thrust bearing annular part, the front axial end faces of the first thrust bearing annular part and the second thrust bearing annular part are flush, the flush front axial end faces of the first thrust bearing annular part and the second thrust bearing annular part jointly form the axial thrust surface, the first thrust bearing annular part and the second thrust bearing annular part are in clearance fit, and the throttle gap is formed between the first thrust bearing annular part and the second thrust bearing annular part.
3. The air float thrust bearing of claim 2, wherein, The first thrust bearing annular part is provided with an outer circumferential surface, the second thrust bearing annular part is provided with an inner circumferential surface, the second thrust bearing annular part is sleeved on the first thrust bearing annular part, and the throttle gap is formed between the outer circumferential surface of the first thrust bearing annular part and the inner circumferential surface of the second thrust bearing annular part.
4. The air float thrust bearing of claim 3, wherein, The first thrust bearing annular part is provided with a radial flange abutting against the second thrust bearing annular part from the rear side in the axial direction.
5. The gas foil thrust bearing of claim 4, wherein, The gas floating thrust bearing is mounted on a bearing seat through screws, the radial flange and the second thrust bearing annular part are provided with axial screw holes at corresponding positions, the axial screw hole of the radial flange is a through hole, the axial screw hole of the second thrust bearing annular part is a blind hole, the screw is connected to the axial screw hole of the second thrust bearing annular part after passing through the axial screw hole of the radial flange, and the first thrust bearing annular part and the second thrust bearing annular part are locked on the bearing seat, and the first thrust bearing annular part and the second thrust bearing annular part are integrally machined to form the flush axial thrust surface.
6. The air float thrust bearing of claim 4, wherein, A sealing ring is arranged between the radial flange and the second thrust bearing annular part.
7. The air float thrust bearing of claim 3, wherein, The outer circumferential surface of the first thrust bearing annular part is provided with a first annular groove and a plurality of air inlet holes communicated with the first annular groove, the air inlet holes extend to a tail end surface of the first thrust bearing annular part, the tail end surface of the first thrust bearing annular part is provided with a second annular groove communicated with the air inlet holes, and the second annular groove, the air inlet holes and the first annular groove form the air inlet channel.
8. The air float thrust bearing of claim 7, wherein, The first annular groove divides the outer circumferential surface of the first thrust bearing annular part into a first outer circumferential surface and a second outer circumferential surface in the axial direction, the first outer circumferential surface is closer to the axial thrust surface than the second outer circumferential surface, the inner circumferential surface of the second thrust bearing annular part is in clearance fit with the first outer circumferential surface, and the inner circumferential surface of the second thrust bearing annular part is in interference fit with the second outer circumferential surface.
9. An electric spindle, characterized by The gas floating thrust bearing comprises the gas floating thrust bearing according to any one of claims 1-8.
10. A machine tool, characterized by The motorized spindle comprises the motorized spindle according to claim 9.