A new type of foil gas dynamic pressure bearing

Abstract

The present application relates to the technical field of gas bearings, and provides a novel foil gas journal bearing, comprising: a bearing sleeve, a multi-layer foil assembly, and a top foil; the multi-layer foil assembly is formed by stacking a plurality of foils, and adjacent foils are offset by a certain distance in the circumferential direction. A single foil is composed of a plurality of flat foils distributed circumferentially and circumferential connecting beams. The flat foils of the upper-layer foil are opposite to the circumferential connecting beams of the lower-layer foil. After installation, the circumferential connecting beams and the ends of the flat foils support the flat foils and make the middle of the flat foils suspended; the top foil is formed by bending a whole flat foil, and the foils do not need to be bent. One end of the top foil and the foils is fixed on the bearing sleeve, and the other end is free. Compared with the traditional foil gas journal bearing, the bearing structure of the present application is simple. The contact points of the multi-layer structure increase the friction damping. The simply supported beam-like structure formed by the flat foils supported by the ends of the flat foils is not prone to plastic deformation and forms a number of local preloads together with the top foil. When designing, by changing the shape change law of the flat foils, the stiffness, damping characteristics and the number of local preloads of the gas bearing can be conveniently changed, and the load-carrying capacity of the gas bearing and the stability of the rotor system can be improved.

Description

Technical Field

[0001] The present invention relates to the technical field of gas dynamic pressure bearings, and particularly relates to a novel foil gas dynamic pressure bearing. Background Art

[0002] Traditional foil gas dynamic pressure bearings are composed of a top foil, a wave foil, and a bearing sleeve. The wave foil is obtained by heat treatment and shaping after being pressed by a concave-convex die from a flat foil. The foil presents a wavy shape and consists of several arc structures, and the foil supports the circular arc top foil. The top foil and the surface of the eccentric rotor enclose the convergence domain and divergence domain of the gas film. The gas film flow rate gradually decreases in the convergence domain where the circumferential space gradually decreases, forming a high-pressure gas film to keep the rotor in a completely suspended state. Therefore, foil gas dynamic pressure bearings have the advantages of oil-free lubrication and high efficiency, and are widely used in high-speed and lightly loaded rotating equipment such as high-speed air circulation machines, fuel cell air compressors, air refrigerators, micro gas turbines, and micro turbojet engines.

[0003] For the bearing structure, the high-pressure gas film is dispersed and loaded onto the foil through the top foil, and multi-point contact friction is formed between the foil and the top foil and the bearing sleeve. After being loaded, the curvature of the arc structure of the foil becomes larger, changing the radial and circumferential displacements of the foil, and providing stiffness and damping characteristics for the bearing. For a rotor with light load and low-amplitude vibration, the foil only undergoes elastic deformation after heat treatment hardening, and the foil returns to its initial state after the rotor stops rotating. However, for a rotor with a large load and large-amplitude vibration, the curvature change of the arc structure of the foil is relatively large, and the foil is plastically deformed before it can fully recover and is then re-acted upon by the rotor load. Moreover, when the rotor is not working, the arc structure of the foil directly below remains in a large-curvature state. After long-term use of the bearing, the curvature of the foil becomes larger, increasing the gas film gap and destroying the system stability. In addition, the damping of traditional foil gas dynamic pressure bearings is only composed of the contact friction between the foil and the top foil and the bearing sleeve. The limited number of concave-convex arcs of the wave foil results in insufficient damping of the bearing, and it is unable to suppress the synchronous vibration and sub-synchronous vibration that occur during high-speed rotation, limiting the application of traditional foil gas dynamic pressure bearings in ultra-high-speed rotating machinery. Summary of the Invention

[0004] In view of the above technical deficiencies, the present application provides a novel foil gas journal bearing, which adopts a plurality of upper foil sheets and lower foil sheets stacked to form a multi-layer foil assembly. A single upper foil sheet and a lower foil sheet are composed of a plurality of flat foils circumferentially distributed and circumferential connecting beams. The flat foils of the upper foil sheet are opposite to the circumferential connecting beams of the lower foil sheet. Due to the different bending stiffnesses of the flat foils and the circumferential connecting beams, the circumferential connecting beams of the upper foil sheet contact the flat foils of the lower foil sheet. The circumferential connecting beams and the ends of the flat foils support the flat foils and make the middle of the flat foils suspended, forming a simply supported beam-like structure to avoid plastic deformation. The stacked plurality of upper foil sheets and lower foil sheets increase the contact points between the flat foils and the circumferential connecting beams, thereby increasing the friction damping of the bearing. The present invention uses a multi-layer foil assembly to replace the single wave foil of the traditional foil gas journal bearing, effectively improving the bearing capacity and durability of the bearing, solving the technical problems of low damping, easy plastic deformation and poor system stability of the existing foil gas journal bearing, and improving the service life of the gas bearing. The preferred technical solutions among the many technical solutions provided by the present invention and the many technical effects they can produce are described below.

[0005] To achieve the above technical objectives, the present invention provides the following technical solutions: A simple-type foil gas journal bearing, comprising: a bearing sleeve, a multi-layer foil assembly, and a top foil. Among them, the multi-layer foil assembly is formed by stacking a plurality of upper foil sheets and lower foil sheets. The adjacent upper foil sheets and lower foil sheets are displaced a certain distance in the circumferential direction. A single upper foil sheet and a lower foil sheet are composed of a plurality of flat foils circumferentially distributed and circumferential connecting beams. The flat foils of the upper foil sheet are opposite to the circumferential connecting beams of the lower foil sheet. After installation, the circumferential connecting beams and the ends of the flat foils support the flat foils and make the middle of the flat foils suspended. The circumferential connecting beams of the upper foil sheet contact the flat foils of the lower foil sheet. The flat foils of the upper foil sheet are between the two flat foils of the lower foil sheet. The flat foils of the topmost upper foil sheet contact and support the top foil. The circumferential connecting beams of the lowermost lower foil sheet contact the bearing sleeve; the top foil is formed by bending a whole flat foil. The upper foil sheets and the lower foil sheets do not need to be bent due to the different bending stiffnesses of the flat foils and the circumferential connecting beams. One end of the top foil and the multi-layer foil assembly is fixed on the bearing sleeve, and the other end is free.

[0006] The multi-layer foil assembly is formed by stacking a plurality of upper foils and lower foils. A single upper foil and lower foil are obtained by cutting local circumferential positions of a whole planar foil through processing methods such as laser cutting or water cutting. After cutting, the planar foil forms several circumferential connecting beams and flat foils. The circumferential connecting beams are used to connect two adjacent flat foils, and adjacent circumferential connecting beams do not touch. The bending stiffness of the circumferential connecting beams is lower than that of the flat foils. After the upper foils and lower foils are installed in the bearing housing, the circumferential connecting beams bend greatly while the flat foils do not bend or bend slightly. The circumferential connecting beams of the upper foils contact the flat foils of the lower foils. The circumferential connecting beams and the ends of the flat foils support the flat foils and make the middle of the flat foils suspended, forming a simply supported beam-like structure, avoiding plastic deformation of the foils and providing a certain support stiffness for the top foil. The stacked plurality of upper foils and lower foils increase the number of contact points between the flat foils and the circumferential connecting beams, thereby increasing the friction damping of the bearing structure. When designing, by changing the shape change law of the flat foils, the stiffness and damping characteristics of the gas bearing can be easily changed, improving the load-carrying capacity of the gas bearing and the stability of the rotor system.

[0007] The circumferential connecting beam is the remaining part after removing some materials from a whole planar foil. Its shape is rectangular, and several are distributed axially. Adjacent circumferential connecting beams do not touch and are used to connect two adjacent flat foils.

[0008] Optionally, the shape of the circumferential connecting beam is an inclined beam, a cross beam, an S-shaped beam, or an X-shaped beam, which is a structure for connecting two adjacent flat foils.

[0009] Optionally, the middle position of one end of the top foil is processed into a groove, and the middle of the other end is processed into a protrusion. The axial dimension of the protrusion part is smaller than the size of the groove at the top end. During installation, the protrusion part at the top end passes through the groove and is inserted into the groove of the bearing housing. Both ends of the top are inserted into the grooves of the bearing housing, restricting the circumferential movement of the multi-layer foil group and realizing the bidirectional rotation of the rotor system.

[0010] Optionally, the multi-layer foil assembly has only one single-layer foil. The planar foil after cutting the single-layer foil forms several circumferential connecting beams and flat foils. The circumferential connecting beams are used to connect two adjacent flat foils, and adjacent circumferential connecting beams do not touch. After the circumferential connecting beams and the flat foils are placed in the bearing housing, their natural bending degrees are different. The flat foils contact and support the top foil, and the circumferential connecting beams contact and support the bearing housing.

[0011] Optionally, during the cutting process of the upper foils and lower foils, the axial distribution of the circumferential connecting beams and the flat foils is realized. Two adjacent flat foils are axially connected by axial connecting beams. The flat foil on the left is axially opposite to the circumferential connecting beam on the right, and one flat foil on the left connects two flat foils on the right.

[0012] Optionally, during processing, the circumferential connecting beam is truncated, the foil becomes a number of first inserts and second inserts, the circumferential connecting beam becomes first insert pins and second insert pins, the positions of the first insert pins are different from those of the second insert pins, the distance between adjacent pins is slightly greater than the width of the pins, the adjacent first inserts and second inserts cross, and the crossed first insert pins and second insert pins support the first inserts and second inserts. The first inserts and second inserts support the top foil, and the top foil between the first inserts and second inserts is in a suspended state, generating bearing support stiffness. When the rotor supported by the bearing is impacted or vibrates greatly, the first inserts and second inserts will be significantly deformed downward. At this time, the top foil is supported by the first insert pins and second insert pins, and the first inserts and second inserts are in a suspended state. The cross-distributed insert pins support the ends of the first inserts and second inserts, resulting in the stiffness of the ends of the first inserts and second inserts being greater than the middle parts of the first inserts and second inserts, making the deformation of the top foil when the rotor is impacted or vibrates with a large amplitude different from the deformation of the top foil when the rotor vibrates slightly. Furthermore, the circumferential distribution of the air film is changed, forming several local wedges or preloads, reducing the continuity of the air film, and changing the stability of the system. At the same time, the contact area between the pins of the first inserts and second inserts and the bearing sleeve increases after being deformed under load, increasing the contact friction of the bearing structure and the energy consumption of the bearing, which is beneficial to the stability of the system.

[0013] Optionally, the top foil is connected end to end with the multi-layer foil group to form an integrated top foil. The circumferential connecting beam is processed at the corresponding circumferential angles as required to make the inner circumferential connecting beam opposite to the outer flat foil.

[0014] The positive effects of the present invention compared with the prior art due to the adoption of the above technologies are as follows:

[0015] (1) In the present invention, a single foil is composed of a flat foil and a circumferential connecting beam. The different stiffnesses of the flat foil and the circumferential connecting beam cause the circumferential connecting beam to contact the bearing sleeve and the flat foil to be in a suspended state after the foil is installed on the bearing sleeve, forming a simply supported beam-like structure. It does not require the concave and convex support effect formed by the mold pressing of the existing wave foil, and the simply supported beam-like structure is not prone to plastic deformation under load, effectively improving the service life of the bearing.

[0016] (2) The present invention uses multiple upper foils and lower foils stacked to form a multi-layer foil assembly. The adjacent foils are displaced by a certain distance in the circumferential direction, and each foil is composed of a flat foil and a circumferential connecting beam, increasing the number of contact points between the circumferential connecting beam and the flat foil. Moreover, the circumferential connecting beam structure has relatively low stiffness, resulting in an increase in the contact area between the circumferential connecting beam and the bearing sleeve or the flat foil, increasing the energy consumption of the bearing structure. Therefore, the bearing structure of the present invention has a relatively large damping, which is beneficial to the stability of the system. Description of the Drawings

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0018] Figure 1 It is an exploded view of a novel foil gas journal bearing provided by an embodiment of the present invention.

[0019] Figure 2 It is a front view and a partial enlarged view of a novel foil gas journal bearing provided by an embodiment of the present invention.

[0020] Figure 3 It is an exploded view of the structure of a novel foil gas journal bearing provided by an embodiment of the present invention.

[0021] Figure 4 It is a schematic diagram of the foil of a novel foil gas journal bearing provided by an embodiment of the present invention.

[0022] Figure 5 It is a schematic diagram of the S-shaped circumferential connecting beam of a novel foil gas journal bearing provided by an embodiment of the present invention.

[0023] Figure 6 It is an exploded view of the bearing with a modified top foil of a novel foil gas journal bearing provided by an embodiment of the present invention.

[0024] Figure 7 It is a front view and a partial enlarged view of the bearing with a modified top foil of a novel foil gas journal bearing provided by an embodiment of the present invention.

[0025] Figure 8 It is a schematic diagram of the modified top foil of a novel foil gas journal bearing provided by an embodiment of the present invention.

[0026] Figure 9 It is an exploded view of the bearing with a single-layer foil of a novel foil gas journal bearing provided by an embodiment of the present invention.

[0027] Figure 10 It is a front view and a partial enlarged view of the bearing with a single-layer foil of a novel foil gas journal bearing provided by an embodiment of the present invention.

[0028] Figure 11 It is a schematic diagram of the modified foil of a novel foil gas journal bearing provided by an embodiment of the present invention.

[0029] Figure 12 It is an exploded view of the bearing with the modified foil 1 of a novel foil gas journal bearing provided by an embodiment of the present invention.

[0030] Figure 13 The front view and partial enlarged view of the modified foil 1 of a novel foil gas journal bearing provided by an embodiment of the present invention.

[0031] Figure 14 Schematic diagram of the modified foil 1 of a novel foil gas journal bearing provided by an embodiment of the present invention.

[0032] Figure 15 Schematic diagram of the integral top foil of a novel foil gas journal bearing provided by an embodiment of the present invention. Among them, the reference numerals of each drawing in the figure: 1 - top foil, 2 - multi-layer foil assembly, 3 - bearing sleeve, 4 - single-layer foil, 5 - first insert piece, 6 - second insert piece, 7 - integral top foil, 21 - upper foil, 22 - lower foil, 51 - first insert piece pin, 61 - second insert piece pin, 211 - flat foil, 212 - circumferential connecting beam, 213 - S-shaped beam, 214 - axial connecting beam Detailed implementation manners

[0033] In order to make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be described in detail below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other implementation manners obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope protected by the present invention.

[0034] In the description of the present invention, it should be noted that unless otherwise specified, the meaning of "several" is two or more; the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inner", "outer", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation of the present invention. The terms "preload" and "wedge" should be understood in a broad sense, that is, the gas film thickness is uneven in the radial direction of the bearing. For example, a preload is applied in advance when the bearing structure is installed, and the effect formed during the operation of the bearing is the same as the preload applied in advance. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0035] The foil gas journal bearing provided by the embodiments of the present application will now be described.

[0036] Refer to Figure 1 As shown, a novel foil gas journal bearing is shown, which is composed of a top foil (1), a multi-layer foil assembly (2), and a bearing sleeve (3).

[0037] As a specific implementation, referring to Figures 1 to 4 As shown, the multi-layer foil assembly (2) is formed by stacking a plurality of upper foils (21) and lower foils (22). A single upper foil (21) and lower foil (22) are obtained by cutting the circumferential local positions of a whole planar foil by processing methods such as laser cutting or water cutting. After cutting, the planar foil forms a plurality of circumferentially distributed connecting beams (212) and circumferentially distributed flat foils (211) axially. The upper foil (21) and the lower foil (22) are displaced by a certain distance so that the flat foil (211) of the upper foil (21) is opposite to the circumferential connecting beam (212) of the lower foil (22). The circumferential connecting beam (212) is used to connect two adjacent flat foils (211), and adjacent circumferential connecting beams (212) do not contact. The bending stiffness of the circumferential connecting beam (212) is lower than that of the flat foil (211). After the upper foil (21) and the lower foil (22) are installed in the bearing housing, the circumferential connecting beam (212) has a large bending deformation while the flat foil (211) has no or little bending deformation. The circumferential connecting beam (212) of the upper foil (21) contacts the flat foil (211) of the lower foil (22), and the ends of the circumferential connecting beam (212) and the flat foil (211) support the flat foil (211) and make the middle of the flat foil (211) suspended. The plurality of stacked upper foils (21) and lower foils (22) increase the number of contact points between the flat foil (211) and the circumferential connecting beam (212); moreover, the stiffness of the circumferential connecting beam (212) is lower than that of the flat foil (211), and the contact area between the circumferential connecting beam (212) and the bearing housing (3) or the flat foil (212) is larger, which can increase the contact friction force, thereby increasing the friction damping of the bearing. The flat foil (211) supported at the ends forms a simply supported beam-like structure and is not prone to plastic deformation, providing a certain support stiffness for the top foil (1). The multi-layer upper foils (21) and lower foils (22) are stacked radially and regarded as multiple foils in series, providing sufficient deformation space for large-amplitude vibrations of the rotor; when designing, by changing the shape change law of the flat foil (211), the stiffness and damping characteristics of the gas bearing can be conveniently changed, and the load-carrying capacity of the gas bearing and the stability of the rotor system can be improved.

[0038] Referring to Figures 3 to 4 As shown, the circumferential connecting beam (212) is the remaining part after removing materials from a whole planar foil, and its shape is rectangular. A plurality of them are distributed axially, and adjacent circumferential connecting beams do not contact and are used to connect two flat foils (211).

[0039] Referring to Figures 1 to 2As shown, the top foil (1) is formed by bending a whole flat foil. The upper foil (21) and the lower foil (22) do not require bending due to the different bending stiffnesses of the flat foil (211) and the circumferential connecting beam (212). One end of the top foil (1) and the multi-layer foil assembly (2) is fixed to the bearing sleeve (3), and the other end is free.

[0040] Referring to Figures 1 to 2 As shown, the bearing sleeve (3) is an annular metal for supporting the top foil (1) and the multi-layer foil group (2).

[0041] As an alternative embodiment, referring to Figure 5 As shown, the shape of the circumferential connecting beam (212) is an S-shaped beam (213), an inclined beam, a cross beam, an X-shaped beam, a structure connecting two adjacent flat foils (211), and the number of the circumferential connecting beams (212) is determined according to actual needs.

[0042] As an alternative embodiment, referring to Figures 3 to 8 As shown, the middle position of one end of the top foil (1) is processed into a groove, and the middle of the other end is processed into a protrusion, and the axial dimension of the protrusion part is smaller than the groove dimension at the top end. During installation, the protrusion part at the top end passes through the groove and is inserted into the groove of the bearing sleeve, and both ends of the top are inserted into the groove of the bearing sleeve to limit the circumferential movement of the multi-layer foil group (2) and realize the bidirectional rotation of the rotor system.

[0043] As an alternative embodiment, referring to Figures 9 to 10 As shown, the multi-layer foil assembly (2) has only one single-layer foil (4). After the circumferential connecting beam (212) and the flat foil (211) of the single-layer foil (4) are placed in the bearing sleeve (3), they bend naturally, and can also support the top foil (1).

[0044] As an alternative embodiment, referring to Figure 11 As shown, during the cutting process of the upper foil (21) and the lower foil (22), the axial distribution of the circumferential connecting beam (212) and the flat foil (211) is realized. Two adjacent flat foils (211) are axially connected by an axial connecting beam (214). The flat foil (211) on the left is axially opposite to the circumferential connecting beam (212) on the right, and one flat foil (211) on the left connects two flat foils (211) on the right.

[0045] As an alternative embodiment, referring to Figures 12 to 14As shown, during the processing, the circumferential connecting beam (212) is truncated, and the foil becomes a number of first inserts (5) and second inserts (6). The circumferential connecting beam (212) becomes the first insert pins and the second insert pins (61). The positions of the first insert pins (51) are different from those of the second insert pins (61). The distance between adjacent pins is slightly greater than the width of the pins. The adjacent first inserts (5) and second inserts (6) cross each other. After crossing, the first insert pins (51) and the second insert pins (61) support the first inserts (5) and the second inserts (6). The first inserts (5) and the second inserts (6) support the top foil. The top foil (1) between the first inserts (5) and the second inserts (6) is in a suspended state, resulting in non-uniformity of the bearing support stiffness. When the rotor supported by the bearing is subjected to impact or large-amplitude vibration, it will cause the first inserts (5) and the second inserts (6) to deform downward. At this time, the top foil (1) is supported by the first insert pins (51) and the second insert pins (61), and the first inserts (5) and the second inserts (6) are in a suspended state, resulting in a change in the deformation of the top foil (1), thereby changing the stability of the system.

[0046] As an alternative embodiment, referring to Figure 15 As shown, the top foil (1) and the multi-layer foil group (2) are connected end to end to form an integrated top foil (7). The circumferential connecting beam is processed at the corresponding circumferential angle of the integrated top foil (7) as required, so that the inner circumferential connecting beam (212) is opposite to the outer flat foil (211).

[0047] The above description is only the preferred embodiment of the present invention and is not a limitation to the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, and modifications made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A novel foil gas dynamic pressure bearing, comprising: A top foil (1), a multi-layer foil assembly (2), and a bearing sleeve (3), characterized in that the multi-layer foil assembly (2) is formed by stacking a plurality of upper foils (21) and lower foils (22), wherein a single upper foil (21) and a single lower foil (22) are obtained by cutting a circumferential local position of a whole flat foil by laser cutting or water jet cutting, and the flat foil after cutting forms a plurality of circumferential connecting beams (212) and a flat foil (211), wherein the circumferential connecting beams (212) are used to connect two adjacent flat foils (211), and the adjacent circumferential connecting beams (212) do not contact each other; The bending stiffness of the connecting beam (212) is lower than the stiffness of the flat foil (211), the bending deformation of the circumferential connecting beam (212) is large while the deformation of the flat foil (211) is small; the adjacent upper foil (21) and the lower foil (22) are offset by a certain distance in the circumferential direction, the flat foil (211) of the upper foil (21) and the circumferential connecting beam (212) of the lower foil (22) are opposite, and after the upper foil (21) and the lower foil (22) are installed in the bearing sleeve, the circumferential connecting beam (212) of the upper foil (21) and the lower foil (22) are offset by a certain distance in the circumferential direction. ), the flat foil (211) of the upper foil (21) is located between the two flat foils (211) of the lower foil (22), the circumferential connecting beam (212) and the end of the flat foil (211) support the flat foil (211) and make the middle of the flat foil (211) suspended, the stacked plurality of upper foils (21) and lower foils (22) increase the contact points between the flat foil (211) and the circumferential connecting beam (212), thereby increasing the friction damping of the bearing, and the quasi-simply-supported beam structure supported by the end of the flat foil (211) is not easy to Plastic deformation occurs, the flat foil (211) of the uppermost layer of the upper foil (21) contacts and supports the top foil (1), providing a certain support stiffness for the top foil (1), and the circumferential connecting beam (212) of the lowermost layer of the lower foil (22) contacts the bearing sleeve (3); the top foil (1) is a whole flat foil formed by bending, the upper foil (21) and the lower foil (22) do not need to be bent due to the different bending stiffness of the flat foil (211) and the circumferential connecting beam (212), one end of the top foil (1) and the multi-layer foil assembly (2) is fixed on the bearing sleeve (3), and the other end is free.

2. According to claim 1, a novel foil gas dynamic pressure bearing is characterized in that: The circumferential connecting beam (212) is the remaining part of the flat foil after the material is cut off, and its shape is rectangular, and is used to connect the two flat foils (211); the shape of the circumferential connecting beam (212) is replaced by an S-shaped beam (213), an oblique beam, a cross beam, or an X-shaped beam to connect the structure of two adjacent flat foils (211).

3. According to claim 1, a novel foil gas dynamic pressure bearing is characterized in that: The middle position of one end of the top foil (1) is processed into a groove, and the middle position of the other end is processed into a protrusion whose axial size is smaller than the size of the groove at the top end. During installation, the protruding part of the top end passes through the groove and is inserted into the groove of the bearing sleeve. Both ends of the top are inserted into the groove of the bearing sleeve, thereby limiting the circumferential movement of the multi-layer foil assembly (2) and realizing bidirectional rotation of the rotor system.

4. According to claim 1, a novel foil gas dynamic pressure bearing is characterized in that: The multi-layer foil assembly (2) has only one single-layer foil (4), and the circumferential connecting beam (212) of the single-layer foil (4) and the flat foil (211) are naturally bent after being placed in the bearing sleeve (3) to support the top foil (1).

5. According to claim 1, a novel foil gas dynamic pressure bearing is characterized in that: The upper foil (21) and the lower foil (22) are cut to achieve axial distribution of the circumferential connecting beam (212) and the flat foil (211), two adjacent flat foils (211) are axially connected by an axial connecting beam (214), the flat foil (211) on the left side is axially opposite to the circumferential connecting beam (212) on the right side, and one flat foil (211) on the left side is connected to two flat foils (211) on the right side.

6. The novel foil gas dynamic pressure bearing according to claim 1 is characterized in that: The circumferential connecting beam (212) is cut off during processing, and the foil becomes a plurality of first insert sheets (5) and second insert sheets (6). The circumferential connecting beam (212) becomes a first insert sheet pin (51) and a second insert sheet pin (61). The position of the first insert sheet pin (51) is different from the position of the second insert sheet pin (61). The distance between adjacent pins is slightly greater than the width of the pins. The adjacent first insert sheets (5) and second insert sheets (6) cross each other. The crossed first insert sheet pin (51) and second insert sheet pin (61) support the first insert sheet (5) and the second insert sheet (6). The first plug-in sheet (5) and the second plug-in sheet (6) support the top foil, and the top foil (1) between the first plug-in sheet (5) and the second plug-in sheet (6) is in a suspended state, resulting in uneven bearing support stiffness; when the rotor supported by the bearing is impacted or vibrates greatly, the first plug-in sheet (5) and the second plug-in sheet (6) are deformed downwards, and at this time, the top foil (1) is supported by the first plug-in sheet pin (51) and the second plug-in sheet pin (61), and the first plug-in sheet (5) and the second plug-in sheet (6) are in a suspended state, resulting in changes in the deformation of the top foil (1), thereby changing the stability of the system.

7. The novel foil gas dynamic pressure bearing according to claim 1 is characterized in that: The top foil (1) and the multi-layer foil assembly (2) are connected end to end to form an integrated top foil (7), and the circumferential connecting beam is processed according to requirements at a corresponding circumferential angle of the integrated top foil (7) to achieve that the inner circumferential connecting beam (212) is opposite to the outer flat foil (211).

Images