A cantilever thrust foil bearing
By using multi-layer sector-shaped elastic support elements and cantilever foil design in cantilever foil bearings, the multiple stiffness structure is formed, which solves the shortcomings of traditional cantilever foil bearings under impact load and vortex, and improves the load force and Impact vibration relief capability.
Patent Information
- Application Number
- CN201810939635.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2018-08-12
- Publication Date
- 2025-02-07
- Estimated Expiration
- 2038-08-12
AI Technical Summary
Due to the single support structure of traditional cantilever foil bearings, it is difficult to effectively deal with impact loads and vortex during operation, resulting in friction damage between the spindle and the foil, with low load force and low ability to alleviate impact vibration.
A cantilever-type thrust foil bearing is designed, using more than three sector-shaped elastic support elements, more than three sector-shaped cantilever foils and more than three pins, and the linear contact between the sector-shaped elastic support elements and the sector-shaped cantilever foils is carried out through the sector-shaped elastic support elements. Or surface contact, and adjacent sector-shaped cantilever foils contact or surface contact, forming a multiple stiffness structure.
The load force of the bearing and the ability to alleviate impact vibration are improved, the load-bearing characteristics and ability to deal with impacts are enhanced, the spindle angle deviation is restored, and the unstable vortex is eliminated.
Smart Images
Figure CN108980198B_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of dynamic pressure gas bearings, in particular to a cantilever thrust foil bearing. Background Art
[0002] In practical applications, when the load-bearing hydrodynamic gas bearing is running, the shaft angle deviation will occur, resulting in reduced load-bearing capacity and severe wear. The foil gas bearing is a hydrodynamic gas bearing with a self-acting flexible surface, and its flexible surface is generally made of metal foil. The foil gas bearing has a certain stiffness and damping due to its flexible surface. It can adaptively change the thickness of the air film in the bearing according to the load conditions, so that the bearing can adapt to the angle deviation of the shaft within a certain range, improve the bearing capacity and the ability to mitigate impact vibration. In recent years, the rapid development of precision machinery and aviation industry has placed higher and higher requirements on bearing systems. In order to improve the high speed and precision of rotary motion machinery, the research and production of gas bearings have received more and more attention, so that foil bearings have achieved a leap forward in recent years. The engineering products of gas bearings have been actually applied to aviation devices and related high-speed rotating machinery products, such as turbo compressors for extremely low temperatures, helium turbine expanders, aircraft air conditioners, etc., and the excellent performance of foil bearings has been verified. However, due to the single supporting structure, the traditional cantilever foil bearing cannot effectively cope with the impact load and vortex during operation through foil deformation, which can easily cause friction damage between the main shaft and the foil.
[0003] It can be seen that in the prior art, the foil can only provide a single stiffness for the cantilever foil bearing, so that the load force of the cantilever foil bearing is relatively low, and the ability to mitigate impact vibration is also relatively low. Summary of the invention
[0004] In view of this, the main object of the present invention is to provide a cantilever thrust foil bearing having multiple stiffnesses, a higher load capacity, and a stronger ability to mitigate impact vibration.
[0005] In order to achieve the above object, the technical solution proposed by the present invention is:
[0006] A cantilever thrust foil bearing, characterized in that the cantilever thrust foil bearing comprises: a bearing seat, more than three fan-shaped elastic support elements, more than three fan-shaped cantilever foils, and more than three pins; wherein the bearing seat comprises a cylindrical support and more than three fan-shaped pads;
[0007] The upper end of the support is evenly provided with more than three positioning slots perpendicular to the main axis along the circumferential direction, and more than three fan-shaped tiles are installed on the upper end of the support; the number of fan-shaped tiles, the number of fan-shaped elastic support elements, the number of fan-shaped cantilever foils, the number of positioning slots and the number of pins are all the same, and the fan-shaped tiles, the fan-shaped elastic support elements, the fan-shaped cantilever foils, the positioning slots and the pins correspond to each other one by one; the circular structure composed of more than three fan-shaped tiles, the circular structure composed of more than three fan-shaped elastic support elements and the circular structure composed of more than three fan-shaped cantilever foils completely overlap, and a center hole for passing the main axis is opened at the center of the overlapped circle; the corresponding fan-shaped tiles, fan-shaped elastic support elements and fan-shaped cantilever foils are installed in sequence from bottom to top on the upper end of the support. arm foil; for more than three positioning slots, a fan-shaped tile perpendicular to the main axis and a corresponding fan-shaped elastic support element perpendicular to the main axis are fixedly installed between adjacent positioning slots, and the fan-shaped elastic support element is in contact with the upper surface of the corresponding fan-shaped tile; the fan-shaped cantilever foil is superimposed on the corresponding fan-shaped elastic support element, and one fan-shaped side of the fan-shaped cantilever foil is fixed in the corresponding positioning slot by pin superposition, and the other fan-shaped side of the fan-shaped cantilever foil is in a free state as the free side, and the free side of each fan-shaped cantilever foil is freely overlapped on the adjacent fan-shaped cantilever foil along the circumferential direction; the fan-shaped elastic support element is in line contact or surface contact with the corresponding fan-shaped cantilever foil, and the adjacent fan-shaped cantilever foils are in segmented line contact or surface contact.
[0008] The fan-shaped elastic support element is in line contact or surface contact with the corresponding fan-shaped cantilever foil, and adjacent fan-shaped cantilever foils are in segmented line contact or surface contact, specifically:
[0009] When the cantilever thrust foil bearing is unloaded, the fan-shaped elastic support element is in line contact with the corresponding fan-shaped cantilever foil at the fixed side, the fan-shaped elastic support element is not in contact with the corresponding fan-shaped cantilever foil at other parts except the fixed side, and adjacent fan-shaped cantilever foils are in line contact at the free overlap.
[0010] When the cantilever thrust foil bearing load is in a first load range, the fan-shaped cantilever foil and the corresponding fan-shaped elastic support element are in line contact at the fixed side and near the center line of the fan-shaped elastic support element, the fan-shaped elastic support element and the corresponding fan-shaped cantilever foil are not in contact at other parts, and adjacent fan-shaped cantilever foils are in line contact at their extended overlaps.
[0011] When the cantilever thrust foil bearing load is in the second load range, the fan-shaped cantilever foil and the corresponding fan-shaped elastic support element are partially in surface contact starting from the fixed end, and adjacent fan-shaped cantilever foils are partially in surface contact at their extended overlaps.
[0012] When the cantilever thrust foil bearing load is in the third load range, the fan-shaped cantilever foil is completely fitted with the corresponding fan-shaped elastic support element, and adjacent fan-shaped cantilever foils are completely fitted with each other at the extended overlapping portion.
[0013] The fan-shaped elastic supporting element is a multi-layer bubbling foil, and the thickness of the multi-layer bubbling foil is 0.1 mm, and the bubbling height of the multi-layer bubbling foil is greater than or equal to 0.2 mm.
[0014] In summary, in the cantilever thrust foil bearing of the present invention, the corresponding fan-shaped pads, fan-shaped elastic support elements, and fan-shaped cantilever foils are installed in sequence from outside to inside in the upper end of the cylindrical support, and the fan-shaped elastic support elements are fitted with the fan-shaped pads. When the cantilever thrust foil bearing is subjected to load, the fan-shaped elastic support element or the fan-shaped cantilever foil is extended. When the load is small, only the fan-shaped cantilever foil is extended under the action of the air film pressure, and only the fan-shaped cantilever foil plays a supporting role. At this time, the cantilever thrust foil bearing has structural damping of the fan-shaped cantilever foil and friction damping between adjacent fan-shaped cantilever foils. As the load increases, the structural damping of the fan-shaped cantilever foil and the friction damping between adjacent fan-shaped cantilever foils in the cantilever thrust foil bearing gradually increase. As the load further increases, the fan-shaped elastic support element and the fan-shaped cantilever foil extend under the action of the air film pressure, and the fan-shaped elastic support element and the fan-shaped cantilever foil jointly play a supporting role. At this time, the cantilever thrust foil bearing has structural damping of the fan-shaped elastic support element, structural damping of the fan-shaped cantilever foil, friction damping between the fan-shaped elastic support element and the fan-shaped cantilever foil, and friction damping between adjacent fan-shaped arm foils; moreover, as the load increases, the above-mentioned friction damping also gradually increases. It can be seen that with the increase of load, the line contact or surface contact between the fan-shaped elastic support element and the corresponding fan-shaped cantilever foil, and the segmented line contact or surface contact between adjacent fan-shaped cantilever foils are further strengthened, and the coupling stiffness between the fan-shaped elastic support element and the fan-shaped cantilever foil is gradually strengthened. The cantilever thrust foil bearing described in the present invention has obvious nonlinear segmented multiple rigidity characteristics and nonlinear segmented damping change characteristics, which greatly improves the bearing capacity and operation stability of the cantilever thrust foil bearing described in the present invention; at the same time, with the increase of load, the mutual coupling between the fan-shaped cantilever foil and the fan-shaped elastic support element makes the cantilever thrust foil bearing described in the present invention exhibit segmented nonlinear stiffness characteristics, further restoring the main shaft angle deviation and eliminating unstable vortex; in this way, the bearing clearance, pressure distribution, etc. are basically consistent along the circumferential direction, so that the cantilever thrust foil bearing described in the present invention has better bearing characteristics and the ability to cope with impact. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1It is a schematic diagram of the overall composition structure of the cantilever thrust foil bearing described in the present invention.
[0016] FIG. 2( a ) is a schematic structural diagram of the cantilever thrust foil bearing of the present invention in an assembled state with the elastic support element and the cantilever foil, and the cantilever foils in contact with each other.
[0017] FIG2( b ) is a schematic structural diagram of the cantilever thrust foil bearing of the present invention, which is subjected to the pressure of the gas film and undergoes overall bending deformation, and the middle area of the thrust foil gradually comes into contact with the elastic support element.
[0018] FIG. 2( c ) is a schematic structural diagram of the cantilever thrust foil and the elastic support element of the present invention in a fully fitted state.
[0019] FIG. 3( a ) is a schematic diagram of the structure of an isohyperelastic support element.
[0020] FIG. 3( b ) is a schematic diagram of the structure of a variable height elastic support element. DETAILED DESCRIPTION
[0021] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0022] Figure 1 FIG. 1 is a schematic diagram of the overall structure of the cantilever thrust foil bearing of the present invention. Figure 1 As shown, the cantilever thrust foil bearing of the present invention comprises: a bearing seat 1, more than three fan-shaped elastic support elements 2, more than three fan-shaped cantilever foils 3, and more than three pins 4; wherein the bearing seat 1 comprises a cylindrical support and more than three fan-shaped pads;
[0023] The upper end of the support is evenly provided with more than three positioning slots perpendicular to the main axis along the circumferential direction, and more than three fan-shaped tiles are installed on the upper end of the support; the number of fan-shaped tiles, the number of fan-shaped elastic support elements 2, the number of fan-shaped cantilever foils 3, the number of positioning slots and the number of pins are all the same, and the fan-shaped tiles, the fan-shaped elastic support elements 2, the fan-shaped cantilever foils 3, the positioning slots and the pins correspond to each other one by one; the circular structure composed of more than three fan-shaped tiles, the circular structure composed of more than three fan-shaped elastic support elements 2, and the circular structure composed of more than three fan-shaped cantilever foils 3 completely overlap, and a center hole for passing the main axis is opened at the center of the overlapped circle; the corresponding fan-shaped tiles, the fan-shaped elastic support elements 2, the fan-shaped cantilever foils 3 are installed in sequence from bottom to top on the upper end of the support. Sheet 3; for more than three positioning slots, a fan-shaped tile perpendicular to the main axis and a corresponding fan-shaped elastic support element 2 perpendicular to the main axis are fixedly installed between adjacent positioning slots, and the fan-shaped elastic support element 2 is in contact with the upper surface of the corresponding fan-shaped tile; the fan-shaped cantilever foil 3 is superimposed on the corresponding fan-shaped elastic support element 2, and one fan-shaped side of the fan-shaped cantilever foil 3 is superimposed and fixed in the corresponding positioning slot through a pin 4 as a fixed side, and the other fan-shaped side of the fan-shaped cantilever foil 3 is in a free state as a free side, and the free side of each fan-shaped cantilever foil 3 is freely overlapped on the adjacent fan-shaped cantilever foil 3 along the circumferential direction; the fan-shaped elastic support element 2 is in line contact or surface contact with the corresponding fan-shaped cantilever foil 3, and the adjacent fan-shaped cantilever foils 3 are in segmented line contact or surface contact.
[0024] In the present invention, the inner diameter and outer diameter of the cantilever thrust foil bearing are 25 mm and 50 mm respectively.
[0025] In summary, in the cantilever thrust foil bearing of the present invention, the corresponding fan-shaped pads, fan-shaped elastic support elements, and fan-shaped cantilever foils are installed in sequence from outside to inside in the upper end of the cylindrical support, and the fan-shaped elastic support elements are fitted with the fan-shaped pads. When the cantilever thrust foil bearing is subjected to load, the fan-shaped elastic support element or the fan-shaped cantilever foil is extended. When the load is small, only the fan-shaped cantilever foil is extended under the action of the air film pressure, and only the fan-shaped cantilever foil plays a supporting role. At this time, the cantilever thrust foil bearing has structural damping of the fan-shaped cantilever foil and friction damping between adjacent fan-shaped cantilever foils. As the load increases, the structural damping of the fan-shaped cantilever foil and the friction damping between adjacent fan-shaped cantilever foils in the cantilever thrust foil bearing gradually increase. As the load further increases, the fan-shaped elastic support element and the fan-shaped cantilever foil extend under the action of the air film pressure, and the fan-shaped elastic support element and the fan-shaped cantilever foil jointly play a supporting role. At this time, the cantilever thrust foil bearing has structural damping of the fan-shaped elastic support element, structural damping of the fan-shaped cantilever foil, friction damping between the fan-shaped elastic support element and the fan-shaped cantilever foil, and friction damping between adjacent fan-shaped arm foils; moreover, as the load increases, the above-mentioned friction damping also gradually increases. It can be seen that as the load increases, the line contact or surface contact between the fan-shaped elastic support element and the corresponding fan-shaped cantilever foil, and the segmented line contact or surface contact between adjacent fan-shaped cantilever foils are further strengthened, and the coupling stiffness between the fan-shaped elastic support element and the fan-shaped cantilever foil is gradually strengthened. The cantilever thrust foil bearing described in the present invention has obvious nonlinear segmented multiple rigidity characteristics and nonlinear segmented damping change characteristics, which greatly improves the bearing capacity and operating stability of the cantilever thrust foil bearing described in the present invention; at the same time, as the load increases, the mutual coupling between the fan-shaped cantilever foil and the fan-shaped elastic support element makes the cantilever thrust foil bearing described in the present invention exhibit segmented nonlinear stiffness characteristics, further restoring the main shaft angle deviation and eliminating unstable vortex; in this way, the bearing clearance, pressure distribution, etc. are basically consistent along the circumferential direction, so that the cantilever thrust foil bearing described in the present invention has better bearing characteristics and the ability to cope with impact.
[0026] Fig. 2(a) is a schematic diagram of the structure of the cantilever thrust foil bearing of the present invention in the assembled state with the elastic support element and the cantilever foil, and the cantilever foils in contact with each other. Fig. 2(b) is a schematic diagram of the structure of the cantilever thrust foil bearing of the present invention in the state of overall bending deformation due to the air film pressure, and the middle area of the thrust foil gradually coming into contact with the elastic support element. Fig. 2(c) is a schematic diagram of the structure of the cantilever thrust foil and the elastic support element of the present invention in a state of complete fit. As shown in Fig. 2(a), Fig. 2(b), and Fig. 2(c), the fan-shaped elastic support element 2 of the present invention is in line contact or surface contact with the corresponding fan-shaped cantilever foil 3, and adjacent fan-shaped cantilever foils 3 are in segmented line contact or surface contact, specifically:
[0027] When the cantilever thrust foil bearing is under no-load, the fan-shaped elastic support element 2 is in line contact with the corresponding fan-shaped cantilever foil 3 at the fixed side, the fan-shaped elastic support element 2 is not in contact with the corresponding fan-shaped cantilever foil 3 at other parts except the fixed side, and adjacent fan-shaped cantilever foils 3 are in line contact at the free overlap.
[0028] In practical applications, since the cantilever thrust foil bearing does not bear load or is not under pressure during assembly, the fan-shaped elastic support element 2 and the fan-shaped cantilever foil 3 are not extended and are in a free state, and adjacent fan-shaped cantilever foils 3 only have line contact at the overlap.
[0029] When the cantilever thrust foil bearing load is in the first load range, the fan-shaped cantilever foil 3 is in line contact with the corresponding fan-shaped elastic support element 2 at the fixed side and near the center line of the fan-shaped elastic support element 2, the fan-shaped elastic support element 2 and the corresponding fan-shaped cantilever foil 3 are not in contact at other parts, and adjacent fan-shaped cantilever foils 3 are in line contact at their extended overlaps.
[0030] In practical applications, since the bearing load of the cantilever thrust foil is small, only the fan-shaped cantilever foil 3 plays a supporting role, and the pressure of the wedge-shaped air film causes the fan-shaped cantilever foil 3 to extend. Except for the fixed side, the fan-shaped cantilever foil 3 and the corresponding fan-shaped elastic support element 2 are in line contact near the center line of the fan-shaped elastic support element 2, and adjacent fan-shaped cantilever foils 3 are in line contact only at the extension.
[0031] When the cantilever thrust foil bearing load is in the second load range, the fan-shaped cantilever foil 3 and the corresponding fan-shaped elastic support element 2 are partially in surface contact starting from the fixed end, and adjacent fan-shaped cantilever foils 3 are partially in surface contact at their extended overlaps.
[0032] In practical applications, due to the large bearing load of the cantilever thrust foil, the pressure of the wedge-shaped air film makes the fan-shaped elastic support element 2 and the fan-shaped cantilever foil 3 play a supporting role together, but at this time the supporting role of the fan-shaped elastic support element 2 is small, and the fan-shaped cantilever foil 3 is still the main support. The fan-shaped elastic support element 2 is extended to a certain extent, and the extension degree of the fan-shaped cantilever foil 3 is further enhanced. A certain degree of surface contact occurs between the fan-shaped elastic support element 2 and the fan-shaped cantilever foil 3, and a certain degree of surface contact also occurs between adjacent fan-shaped cantilever foils 3 at the extension. Moreover, within the second load range, the greater the bearing load of the cantilever thrust foil, the greater the degree of surface contact between the fan-shaped elastic support element 2 and the fan-shaped cantilever foil 3, and the greater the surface contact between adjacent fan-shaped cantilever foils 3.
[0033] When the cantilever thrust foil bearing load is in the third load range, the sector-shaped cantilever foil 3 is completely fitted with the corresponding sector-shaped elastic support element 2, and adjacent sector-shaped cantilever foils 3 are completely fitted with each other at the extended overlapping portion.
[0034] In practical applications, as the bearing load of the cantilever thrust foil increases further, the pressure of the wedge-shaped air film causes the fan-shaped elastic support element 2 and the fan-shaped cantilever foil 3 to play a supporting role together, but at this time, the supporting role of the fan-shaped elastic support element 2 is enhanced, and the supporting role of the fan-shaped cantilever foil 3 is also strengthened to a certain extent, and the fan-shaped elastic support element 2 and the fan-shaped cantilever foil 3 are fitted and extended, and the surface contact degree of adjacent fan-shaped cantilever foils 3 at the extension is further increased. Within the third load range, the greater the bearing load of the cantilever thrust foil, the tighter the fit between the fan-shaped elastic support element 2 and the fan-shaped cantilever foil 3, the stronger the ductility, and the greater the surface contact between adjacent fan-shaped cantilever foils 3, until the common supporting role between the fan-shaped elastic support element 2 and the fan-shaped cantilever foil 3, and the common supporting role between adjacent fan-shaped cantilever foils 3 are completely released.
[0035] In the present invention, the maximum and minimum values of the first load range, the second load range, and the third load range are gradually increased. Under different working conditions, the first load range, the second load range, and the third load range will vary greatly and need to be determined specifically according to actual conditions. Examples are as follows:
[0036] When the parameters of the cantilever thrust foil bearing are configured as follows: the inner diameter and outer diameter of the cantilever thrust foil bearing are 12 mm and 34 mm respectively; the number of fan-shaped cantilever foils is 4, and the opening angle of the fan-shaped cantilever foil is 120°; the slope duty ratio is 20%, and the slope height is 0.2 mm; the fan-shaped cantilever foil is made of nickel-based alloy, and the thickness of the fan-shaped cantilever foil is 0.1 mm; the material of the two layers of bubbling foil as the elastic supporting element is beryllium bronze, the thickness of the two layers of bubbling foil is 0.07 mm, and the bubbling height of the two layers of bubbling foil is 0.2 mm; the bubbles of the two layers of bubbling foil are evenly distributed circumferentially and inserted axially, and each bubbling foil adopts two circles of bubbles: the inner circle has 3 bubbles and the outer circle has 6 bubbles. Under this working condition, the first load range is 0N<T≤8N, the second load range is 8N<T≤30N, and the third load range is T>30N; wherein T is the load of the cantilever radial foil bearing, and N represents the unit of force, Newton.
[0037] When the parameters of the cantilever thrust foil bearing are configured as follows: the inner diameter and outer diameter of the cantilever thrust foil bearing are 12 mm and 34 mm respectively; the number of fan-shaped cantilever foils is 6, and the opening angle of the fan-shaped cantilever foil is 80°; the slope duty ratio is 20%, and the slope height is 0.2 mm; the material of the fan-shaped cantilever foil is nickel-based alloy, and the thickness of the fan-shaped cantilever foil is 0.1 mm; the material of the two layers of bubbling foil as the elastic supporting element is beryllium bronze, the thickness of the two layers of bubbling foil is 0.07 mm, and the bubbling height of the two layers of bubbling foil is 0.2 mm; the bubbles of the two layers of bubbling foil are evenly distributed circumferentially and inserted axially, and each bubbling foil adopts two circles of bubbles: the inner circle is 2 bubbles and the outer circle is 4 bubbles. Under this working condition, the first load range is 0N<T≤15N, the second load range is 15N<T≤40N, and the third load range is T>40N.
[0038] When the parameters of the cantilever thrust foil bearing are configured as follows: the inner diameter and outer diameter of the cantilever thrust foil bearing are 12 mm and 34 mm respectively; the number of fan-shaped cantilever foils is 4, and the opening angle of the fan-shaped cantilever foil is 120°; the slope duty ratio is 20%, and the slope height is 0.2 mm; the material of the fan-shaped cantilever foil is nickel-based alloy, and the thickness of the fan-shaped cantilever foil is 0.12 mm; the material of the two layers of bubbling foil as the elastic supporting element is beryllium bronze, the thickness of the two layers of bubbling foil is 0.07 mm, and the bubbling height of the two layers of bubbling foil is 0.2 mm; the bubbles of the two layers of bubbling foil are evenly distributed circumferentially and inserted axially, and each bubbling foil adopts two circles of bubbles: the inner circle has 3 bubbles and the outer circle has 6 bubbles. Under this working condition, the first load range is 0N<T≤10N, the second load range is 10N<T≤35N, and the third load range is T>35N.
[0039] In the present invention, the fan-shaped elastic support element 2 is a multi-layer bubbling foil, and the thickness of the multi-layer bubbling foil is 0.1 mm, and the bubbling height of the multi-layer bubbling foil is greater than or equal to 0.2 mm. Figure 3(a) is a schematic diagram of the structure of an iso-elastic support element. Figure 3(b) is a schematic diagram of the structure of a variable-height elastic support element. As shown in Figures 3(a) and 3(b), the height of the fan-shaped elastic support element 2 is equal from the fixed side to the free side of the fan-shaped elastic support element 2; or, from the fixed side to the free side of the fan-shaped elastic support element 2, the height of the fan-shaped elastic support element 2 is from low to high and then to low.
[0040] In practical applications, the cantilever thrust foil bearing described in the present invention can also optimize the wedge-shaped gap in the bearing by changing the structural characteristics of the fan-shaped elastic support element 2 to improve the bearing capacity, ensure that the bearing has better stability and impact resistance under large impact loads, and alleviate the foil wear problem of the traditional cantilever thrust foil bearing under heavy loads and impact loads. When a multi-layer bubble foil is used as the fan-shaped elastic support element, the changeable structural parameters include the bubble foil thickness, the number of bubble foil layers, the number of bubbles per unit area, the arrangement of bubbles in a row or in a row, the shape of the bubble, the height of the bubble, etc.
[0041] During actual use, the height distribution of fan-shaped elastic support element 2 can be used to make fan-shaped cantilever foil 3 and fan-shaped elastic support element 2 obtain different contact states. Fan-shaped elastic support element equal height is compared with height gradually rising and reducing again, and fan-shaped elastic support element of equal height has larger nonlinear stiffness characteristic in identical load growth process. In practical application, the height distribution of fan-shaped elastic support element can be selected as required. As by increasing the height of fan-shaped elastic support element 2, the situation that fan-shaped cantilever foil 3 and fan-shaped elastic support element 2 contact can be made bearing in identical load variation process faster, and the contact area maximization of fan-shaped cantilever foil 3 and fan-shaped elastic support element 2 can be reached under smaller load.
[0042] In practical applications, the fan-shaped elastic support elements corresponding to different slots can adopt different structural parameters to control the stiffness of the cantilever thrust foil bearing under large loads, further optimize the wedge gap in the bearing to increase the load-bearing area, and further improve the bearing capacity of the bearing.
[0043] In the present invention, the fan-shaped cantilever foil 3 is made of stainless steel, beryllium bronze or nickel-based alloy, and the thickness of the fan-shaped cantilever foil 3 is 0.1 mm.
[0044] In the present invention, the opening angle α of the fan-shaped tile and the opening angle β of the fan-shaped elastic support element 2 are The opening angle γ of the fan-shaped cantilever foil 3 is Wherein, M represents the number of fan-shaped tiles, the number of fan-shaped elastic support elements 2 or the number of fan-shaped cantilever foils 3, and M is a natural number greater than zero. Here, the opening angle γ of the fan-shaped cantilever foil 3 satisfies The condition is to ensure that adjacent fan-shaped cantilever foils 3 overlap.
[0045] In the present invention, the bearing seat is made of stainless steel, beryllium bronze or nickel-based alloy.
[0046] Example
[0047] In the above-mentioned cantilever thrust foil bearing, the support is cylindrical, and the upper end surface of the support is evenly distributed with 6 fan-shaped tiles, 6 fan-shaped elastic support elements, and 6 fan-shaped cantilever foils. The thickness of the fan-shaped cantilever foil is 0.1 mm, the fan-shaped cantilever foil opening angle is 90°, and the fan-shaped cantilever foil material is nickel-based alloy; the fan-shaped elastic support element is a bubbling foil, the thickness of the bubbling foil is 0.1 mm, and the bubbling height is 0.2 mm. Through experiments, it was found that the cantilever radial foil bearing with a shaft diameter of 25 mm, using a double-layer bubbling foil as an elastic support element, has a main frequency amplitude of only about half of that of a traditional cantilever thrust foil bearing under the same parameters at a speed of 80,000 rpm and a load of 30N. This shows that the cantilever thrust foil bearing described in the present invention has a better ability to dissipate eddy energy and maintain stable operation of the main shaft. At the same time, at a rotation speed of 80 thousand revolutions per minute, the measured ultimate bearing capacity of the cantilever thrust foil bearing of the present invention is increased by about 40% compared with the traditional cantilever thrust foil bearing under the same parameters.
[0048] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A cantilever thrust foil bearing, characterized in that: The cantilever thrust foil bearing comprises: a bearing seat, more than three fan-shaped elastic support elements, more than three fan-shaped cantilever foils, and more than three pins; wherein the bearing seat comprises a cylindrical support and more than three fan-shaped pads; The upper end of the support is evenly provided with more than three positioning slots perpendicular to the main axis along the circumferential direction, and more than three fan-shaped tiles are installed on the upper end of the support; the number of fan-shaped tiles, the number of fan-shaped elastic support elements, the number of fan-shaped cantilever foils, the number of positioning slots and the number of pins are all the same, and the fan-shaped tiles, the fan-shaped elastic support elements, the fan-shaped cantilever foils, the positioning slots and the pins correspond to each other one by one; the circular structure composed of more than three fan-shaped tiles, the circular structure composed of more than three fan-shaped elastic support elements and the circular structure composed of more than three fan-shaped cantilever foils completely overlap, and a center hole for passing the main axis is opened at the center of the overlapped circle; the corresponding fan-shaped tiles, fan-shaped elastic support elements and fan-shaped cantilever foils are installed in sequence from bottom to top on the upper end of the support. arm foil; for more than three positioning slots, a fan-shaped tile perpendicular to the main axis and a corresponding fan-shaped elastic support element perpendicular to the main axis are fixedly installed between adjacent positioning slots, and the fan-shaped elastic support element is in contact with the upper surface of the corresponding fan-shaped tile; the fan-shaped cantilever foil is superimposed on the corresponding fan-shaped elastic support element, and one fan-shaped side of the fan-shaped cantilever foil is fixed in the corresponding positioning slot by pins, and the other fan-shaped side of the fan-shaped cantilever foil is in a free state as a free side, and the free side of each fan-shaped cantilever foil is freely overlapped on the adjacent fan-shaped cantilever foil along the circumferential direction; the fan-shaped elastic support element is in line contact or surface contact with the corresponding fan-shaped cantilever foil, and the adjacent fan-shaped cantilever foils are in segmented line contact or surface contact; The fan-shaped elastic support element is in line contact or surface contact with the corresponding fan-shaped cantilever foil, and adjacent fan-shaped cantilever foils are in segmented line contact or surface contact, specifically: When the cantilever thrust foil bearing is unloaded, the fan-shaped elastic support element and the corresponding fan-shaped cantilever foil are in line contact at the fixed side, the fan-shaped elastic support element and the corresponding fan-shaped cantilever foil are not in contact at other parts except the fixed side, and adjacent fan-shaped cantilever foils are in line contact at the free overlap; When the cantilever thrust foil bearing load is in a first load range, the fan-shaped cantilever foil and the corresponding fan-shaped elastic support element are in line contact at the fixed side and near the center line of the fan-shaped elastic support element, the fan-shaped elastic support element and the corresponding fan-shaped cantilever foil are not in contact at other parts, and adjacent fan-shaped cantilever foils are in line contact at their extended overlaps; When the cantilever thrust foil bearing load is in the second load range, the fan-shaped cantilever foil and the corresponding fan-shaped elastic support element are partially in surface contact starting from the fixed end, and adjacent fan-shaped cantilever foils are partially in surface contact at their extended overlaps; When the cantilever thrust foil bearing load is in the third load range, the fan-shaped cantilever foil is completely fitted with the corresponding fan-shaped elastic support element, and adjacent fan-shaped cantilever foils are completely fitted with each other at the extended overlap portion; The fan-shaped elastic supporting element is a multi-layer bubbling foil, and the thickness of the multi-layer bubbling foil is 0.1 mm, and the bubbling height of the multi-layer bubbling foil is greater than or equal to 0.2 mm.
2. The cantilever thrust foil bearing according to claim 1, characterized in that: The height of the fan-shaped elastic supporting element is equal from the fixed side to the free side of the fan-shaped elastic supporting element.
3. The cantilever thrust foil bearing according to claim 1, characterized in that: From the fixed side to the free side of the fan-shaped elastic supporting element, the height of the fan-shaped elastic supporting element is from low to high and then to low.
4. The cantilever thrust foil bearing according to any one of claims 1 to 3, characterized in that: The fan-shaped cantilever foil is made of stainless steel, beryllium bronze or nickel-based alloy, and the thickness of the fan-shaped cantilever foil is 0.1 mm.
5. The cantilever thrust foil bearing according to claim 4, characterized in that: The opening angle α of the fan-shaped tile and the opening angle β of the fan-shaped elastic support element are: The opening angle γ of the fan-shaped cantilever foil is Wherein, M represents the number of sector-shaped tiles, the number of sector-shaped elastic support elements or the number of sector-shaped cantilever foils, and M is a natural number greater than zero.
6. The cantilever thrust foil bearing according to any one of claims 1 to 3 or 5, characterized in that: The bearing seat is made of stainless steel, beryllium bronze or nickel-based alloy.
7. The cantilever thrust foil bearing according to claim 4, characterized in that: The bearing seat is made of stainless steel, beryllium bronze or nickel-based alloy.
Citation Information
Patent Citations
Cantilever type thrust foil bearing
CN209212776U