A method for installing a foil hydrodynamic gas thrust bearing

Abstract

The present invention discloses a new method for installing a foil hydrodynamic gas thrust bearing, which includes a bearing housing, a pad, a countersunk screw, a flat head screw, an elastic bottom foil and a top foil. Both the elastic bottom foil and the top foil are composed of a straight section and a duty cycle section (perpendicular to the straight section), and the duty cycle section is provided with screw through holes; the pad is fan-shaped, and threaded holes are respectively opened at the bottom and the side, and the elastic bottom foil and the top foil are connected to the side of the pad through flat head screws; countersunk screw holes are evenly distributed along the circumference on the bearing housing, and the pads are evenly distributed on the bearing housing and are fastened and positioned by countersunk screws. The present invention adopts a modular split structure. Compared with the integral welding structure, the process difficulty is low, and it is easy to standardize and carry out assembly line operation; the pad unit is fastened and positioned by flat head screws, reducing the defective rate; the pads of the bearing unit are evenly distributed, improving the force uniformity of the bearing and solving the problem of high installation accuracy requirements for the existing foil hydrodynamic gas thrust bearing.

Description

Technical Field

[0001] The present invention relates to the field of high-speed rotating machinery and gas lubrication, and particularly to a new method for installing a foil hydrodynamic gas thrust bearing. Background Art

[0002] At present, the studied foil hydrodynamic gas bearings have good stability, reliability and impact resistance at high speeds, and are widely used in various high-speed rotating machinery such as high-speed turbojet engines, high-speed cryogenic turboexpanders, high-speed oil-free centrifugal air compressors for the oxygen supply system of fuel cell vehicles, and small high-speed gas turbines for aircraft, with broad development prospects. However, in the continuous application process, the foil hydrodynamic gas bearings adopt a matching design method without standardized and serialized general criteria; the structure of the foil hydrodynamic gas bearings is continuously improved, and it is difficult to establish an accurate conclusion analysis model, and the theoretical analysis lags behind the experiment.

[0003] The applicant found that the centralized assembly method in which the foil of the existing foil hydrodynamic gas thrust bearing is directly welded to the bearing housing has characteristics such as difficult processing and assembly, uneven stress, high defective product rate and low reliability during the assembly process. At present, the technical problem of high precision in the manufacturing and installation process still exists. Therefore, we invented a new method for manufacturing and installing and positioning the foil hydrodynamic gas thrust bearing, which effectively solves the above problems. Summary of the Invention

[0004] The present application provides a new method for manufacturing, installing and positioning a foil hydrodynamic gas thrust bearing, modifies the bearing processing and installation process flow, adopts a distributed installation method to facilitate timely replacement of the same series, decomposes the bearing installation difficulty, and effectively solves the performance defects of difficult processing and assembly, high defective product rate, low reliability, uneven stress and slow heat dissipation during the assembly process of the existing foil hydrodynamic gas thrust bearing, as well as the technical problem of high precision in the manufacturing and installation process.

[0005] The present invention provides the following technical solutions:

[0006] A new method for installing a foil hydrodynamic gas thrust bearing according to the present invention includes a bearing housing, a pad, a countersunk head screw, a flat head screw, an elastic support bottom foil and a top foil. Both the elastic support bottom foil and the top foil are fan-shaped, and are each composed of a straight section of the working plane and a duty cycle section (perpendicular to the straight section) for fastening and positioning the flat head screw. A screw through hole is provided in the duty cycle section; the pad is fan-shaped, and threaded holes are respectively opened at the bottom and the side. The elastic support bottom foil and the top foil are connected to the side of the pad through flat head screws; countersunk head screw holes are evenly distributed along the circumference on the bearing housing, the pads are evenly distributed on the bearing housing, and are fastened and positioned through countersunk head screws; in the installed bearing, the bearing housing, the pads, the elastic support bottom foil and the top foil are stacked in sequence.

[0007] Furthermore, the elastic foil can be of the wave foil type, wire mesh type, bubbling type or other elastic support types; screw holes are provided in the duty section, and the screw holes are through holes.

[0008] Furthermore, threaded holes are provided at the bottom of the pad, and the threaded holes can be blind holes or through holes, and the two bottom surfaces of the pad are parallel; threaded holes are provided on the side of the pad, and the threaded holes are blind holes and the number is two or more.

[0009] Furthermore, after installation with flat head screws, the inner circle of the elastic bottom foil and the flat foil coincides with the inner cylindrical surface of the pad, and the edge side surfaces coincide with each other.

[0010] Furthermore, the foil and the pad are fixed by flat head screws, the pads are evenly distributed on the bearing housing, fastened and positioned by countersunk head screws, and the bearing housing is equally divided into four parts or multiple parts along the circumferential direction by the pads.

[0011] Furthermore, the pads are evenly distributed on the bearing housing, and there is a micro-gap between the flat head screws on adjacent pads to ensure uniform centering of the pad installation.

[0012] Furthermore, the new method for installing the foil hydrodynamic gas thrust bearing is as follows in terms of manufacturing steps:

[0013] (1) Design and manufacture the elastic support bottom foil and top foil, and bend the duty section by 90° so that it is perpendicular to the straight section, and the outer contour of the formed elastic support bottom foil and top foil coincides;

[0014] (2) Stack the elastic support bottom foil and top foil, ensure that the inner circles of the elastic support bottom foil and top foil coincide with the inner circle of the pad, and the duty section of the bent foil coincides with the side surface of the pad, and fasten and position with flat head screws;

[0015] (3) Place the installed pads on the bearing housing, align the threaded holes on the back of the pads with a certain countersunk hole on the bearing housing, and connect the pads to the bearing housing with countersunk head screws. After installation, appropriately adjust the positions of the pads to ensure the uniformity of the circumferential distribution of the pads, and then tighten the countersunk head screws.

[0016] The new method for installing a foil hydrodynamic gas thrust bearing provided by the present invention modifies the bearing processing and installation process flow. This method first fixes the elastic support bottom foil and top foil to the pad in sequence through flat head screws, and then tightens and positions the pad by using countersunk head screws, and installs the bearing by using a distributed installation method. When problems occur in the positioning and fastening of the pad, the elastic support bottom foil and top foil with flat head screws, the integral foil and pad welded and installed in the same series can be used for timely replacement; the pads are evenly distributed in the circumferential direction of the bearing housing, improving the evenness of the bearing force. The difficulty of bearing processing and assembly is decomposed, the installation evenness and efficiency are improved, making the installation simple, the processing convenient, and the precision requirement relatively low, and it is easy to mass produce. Generally, the new method for manufacturing and installing and positioning the foil hydrodynamic gas thrust bearing provided by the present invention effectively solves the performance defects of the existing foil hydrodynamic gas thrust bearing in the assembly process, such as difficult processing and assembly, high defective rate, low reliability, uneven force, and slow heat dissipation, and the technical problem of high precision in the manufacturing and installation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings forming a part of this application are used to provide a further understanding of this application, making other features, objects, and advantages of this application more obvious. The schematic embodiments and descriptions of the drawings of this application are used to explain this application and do not constitute an improper limitation of this application. In the drawings:

[0018] Figure 1 It is a top view of a device adopted by the new method for installing a foil hydrodynamic gas thrust bearing provided by an embodiment of the present invention;

[0019] Figure 2 It is a schematic structural diagram of each component of a device adopted by the new method for installing a foil hydrodynamic gas thrust bearing provided by an embodiment of the present invention;

[0020] Figure 3 It is a schematic diagram of the pad, elastic support bottom foil and top foil of a device adopted by the new method for installing a foil hydrodynamic gas thrust bearing provided by an embodiment of the present invention being fastened and positioned through flat head screws;

[0021] Figure 4 It is a schematic structural diagram of the bearing housing of a device adopted by the new method for installing a foil hydrodynamic gas thrust bearing provided by an embodiment of the present invention;

[0022] Figure 5 It is a schematic diagram of the bearing housing and the pad being fastened and positioned by screws of a device adopted by the new method for installing a foil hydrodynamic gas thrust bearing provided by an embodiment of the present invention.

[0023] Schematic structural diagram of the bearing piece of a device adopted by the new method for installing a foil hydrodynamic gas thrust bearing according to an embodiment of this application, description of reference numerals:

[0024] 1. Bearing housing; 11. Fixed groove; 12. Countersunk screw hole; 2. Countersunk screw; 3. Pad; 31. Countersunk screw hole (blind hole); 32. Flat head screw hole (blind hole); 4. Elastic support bottom foil; 41. Elastic support bottom foil duty section; 42. Elastic support bottom foil working section; 43. Elastic support bottom foil duty section screw hole (through hole); 5. Top foil; 51. Top foil duty section; 52. Top foil working section; 53. Top foil duty section screw hole (through hole); 6. Flat head screw. Detailed implementation mode

[0025] In order to enable the personnel in the technical field to better understand the purpose, technical solution and advantages of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the scope of protection of this application.

[0026] As Figure 1 shown, the present invention provides a foil hydrodynamic gas thrust bearing, including a bearing housing 1, a countersunk screw 2, a pad 3, an elastic support bottom foil 4, a top foil 5 and a flat head screw 6. The elastic support bottom foil 4 and the top foil 5 are superposed and sequentially connected to the pad 3, and are fastened and positioned by the flat head screw 6; the bearing housing 1 and the pad 3 are fastened and positioned by the countersunk screw 2, and the pads 3 are evenly distributed on the bearing housing 1.

[0027] As Figures 2-3 shown, the elastic support bottom foil 4 and the top foil 5 are installed in the flat head screw blind hole 32 on the side of the pad 3 through the flat head screw hole 43 in the elastic support bottom foil duty section 41, the flat head screw hole 53 in the top foil duty section 51 and the flat head screw 6; the matching installation method of the pad 3, the elastic support bottom foil 4 and the top foil 5 can realize multiple uses and series replacement, so as to achieve the effects of simplifying the processing technology, improving the processing efficiency, reducing the defective rate and the processing and assembly difficulty; the even distribution of the pads 3 on the bearing housing 1 can realize uniform force; the elastic support bottom foil working section 42 and the top foil working section 52 form a wedge-shaped space with the shaft shoulder of the rotating shaft to form a hydrodynamic gas film, making the cooperation between the top foil and the rotating shaft smoother, so that the bearing has a higher load-carrying capacity.

[0028] As Figure 4 shown, the bearing housing 1 refers to the base of the bearing, and is circumferentially fixed through the fixed groove 11, which can realize the fixation and support of the main shaft; a plurality of countersunk screw holes 12 are evenly distributed at the bottom of the bearing housing 1, which are used for fastening and positioning between the bearing housing 1 and the pad 3 through the countersunk screw 2, and can realize the fixation of the pad 3 on the upper side of the bearing housing 1.

[0029] As Figure 5 shown, the bearing housing 1 and the pad 3 are fastened and positioned by the countersunk head screws 2. The countersunk head screw holes 31 at the bottom of the pad 3 are blind holes, which will not affect the formation of the hydrodynamic gas film. When the threaded holes on the back of the pad 3 are through holes, gaskets need to be added at the bottom of the bearing housing to prevent air leakage, thus affecting the formation of the hydrodynamic gas film.

[0030] Although the present invention has been described in detail with general descriptions and specific embodiments above, the present application is not limited to the details shown. For those skilled in the art, they can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. Therefore, these modifications or improvements made without departing from the spirit of the present invention all fall within the scope of protection required by the present invention.

Claims

1. A method for installing a foil hydrodynamic gas thrust bearing, characterized in that, The bearing includes a bearing housing, pad, countersunk screw, flat head screw, elastic support bottom foil and top foil; the elastic support bottom foil and top foil are both fan-shaped, and each consists of a straight section on the working plane and a duty section perpendicular to the straight section for fastening and positioning with flat head screws. The duty section is provided with screw through holes; the pad is fan-shaped, and threaded holes are respectively opened at the bottom and side. The elastic support bottom foil and top foil are connected to the side of the pad through flat head screws; countersunk screw holes are evenly distributed along the circumference on the bearing housing. The pads are evenly distributed on the bearing housing and are fastened and positioned by countersunk screws; in the installed bearing, the bearing housing, pad, elastic support bottom foil and top foil are stacked in sequence; The elastic foil is of wave foil type, metal wire mesh type or bubble type; screw holes are provided in the duty section, and the screw holes are through holes; The bottom of the pad is provided with a threaded hole, which can be a blind hole or a through hole, and the two bottom surfaces of the pad are parallel; the side of the pad is provided with threaded holes, which are blind holes and the number is multiple; After being installed with flat head screws, the inner circles of the elastic bottom foil and flat foil coincide with the inner cylindrical surface of the pad, and the edge side surfaces coincide with each other; The foil and the pad are fixed by flat head screws. The pads are evenly distributed on the bearing housing and are fastened and positioned by countersunk screws. The pads divide the bearing housing into multiple parts along the circumferential direction; The bearing housing is circumferentially fixed through a fixing groove; The manufacturing steps are as follows: (1) Design and manufacture the elastic support bottom foil and top foil, and bend the duty section by 90° to make it perpendicular to the straight section. The outer contour of the formed elastic support bottom foil and top foil coincides; (2) Stack the elastic support bottom foil and top foil, ensure that the inner circles of the elastic support bottom foil and top foil coincide with the inner circle of the pad, and the duty section of the bent foil coincides with the side of the pad, and fasten and position with flat head screws; (3) Place the installed pad on the bearing housing, align the threaded hole on the back of the pad with a certain countersunk hole on the bearing housing, and connect the pad to the bearing housing through a countersunk screw; after installation, appropriately adjust the positions of the pads to ensure the uniformity of the circumferential distribution of the pads, and then tighten the countersunk screws.

2. The method for installing a foil hydrodynamic gas thrust bearing according to claim 1, characterized in that, The pads are evenly distributed on the bearing housing, and there is a micro-gap between the flat head screws on adjacent pads to ensure uniform centering of the pad installation.

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