Composite extrusion oil film damper for vertical rotor overspeed tester
By combining particle damping and squeeze film technology in a vertical rotor overspeed tester, the vibration problem of the squeeze film damper at high frequency and large amplitude is solved, achieving better vibration reduction effect and convenient installation.
Patent Information
- Application Number
- CN202423011931.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-06
- Publication Date
- 2025-09-16
- Estimated Expiration
- 2034-12-06
AI Technical Summary
Existing squeeze film dampers are prone to "bistable jump" and "locking" problems caused by excessive inner ring vibration amplitude under high-frequency and large-amplitude working conditions. They are also inconvenient to install and are limited by the space at the bearing and the oil supply system.
A composite squeeze film damper is used, combining particle damping and squeeze film vibration reduction technologies. By filling damping particles in the bearing sleeve and designing independent oil supply and return oil circuits, a composite squeeze film damper is formed, which utilizes the dual energy consumption of particle collision and oil film extrusion to reduce the vibration amplitude.
It effectively solves the "bistable jump" and "locking" problems under high-frequency and large-amplitude working conditions, improves the vibration reduction effect, and realizes standardized design and convenient installation.
Smart Images
Figure CN223344571U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of high-speed rotation test equipment, in particular to a composite squeeze film damper for a vertical rotor overspeed tester. Background Art
[0002] Squeeze film dampers are widely used in the field of aviation engines for high and low pressure rotor vibration reduction. Their structure is that a sleeve is interference-fitted on the outer ring of the bearing as the inner ring of the damper. There is a gap fit between the sleeve and the bearing seat. The gap is filled with flowing lubricating oil to limit the rotation of the inner ring so that it can only move horizontally. The vibration of the shaft system is transmitted to the inner ring through the bearing, thereby squeezing the lubricating oil in the gap to form an oil film reaction force, which consumes the vibration energy and plays a vibration reduction role.
[0003] The overspeed tester adopts a vertical structure. The top of its rotating shaft is fixed to the drive unit, and the rotor test piece is suspended at its bottom. The shaft is driven by the drive unit to achieve high-speed rotation. The vibration damper is located in the lower center of the rotating shaft and fixed to the drive unit. They share the same oil supply line. Its structure is similar to the squeeze film damper used in aircraft engines.
[0004] Commonly used squeeze film dampers are limited by the installation space at the bearing and the oil supply system. Their designs are specifically designed for different structures, have certain limitations, and are not convenient to install.
[0005] The squeeze film damper is a nonlinear damper. When the test rotor is at high speed and has a large imbalance (referring to the imbalance of the rotor test piece suspended at the lower end of the rotating shaft 1), the oil film stiffness increases highly nonlinearly with the increase of the inner ring vibration amplitude. In addition, the two parts forming the oil film are clearance-fitted, which can easily lead to serious consequences such as "bistable jump" and "locking", thereby causing the rotor system to vibrate excessively or even collide, rub, and fatigue failure. Utility Model Content
[0006] In response to the problems existing in the use of squeeze film dampers under high-frequency and large-amplitude working conditions, the utility model provides a composite squeeze film damper for a vertical rotor overspeed tester, which introduces squeeze film vibration reduction technology and particle damping vibration reduction technology, organically combines particle damping vibration reduction and squeeze film vibration reduction to form a composite squeeze film damper, and solves the problems of "bistable jump" and "locking" caused by excessive inner ring vibration amplitude of the squeeze film damper under high-frequency and large-amplitude working conditions.
[0007] To achieve the above objectives, the present invention provides the following technical solutions:
[0008] A composite squeeze film damper for a vertical rotor overspeed tester, comprising a bearing gland, a damping seat, a bearing sleeve, damping particles, a bearing, a retaining ring, and an oil supply and return oil passage;
[0009] The two bearings in the bearing sleeve are respectively placed at the upper and lower ends of the retaining ring and connected to the bearing sleeve; the bearing sleeve has a cavity structure, and the inner cavity is used to fill the damping particles; the bearing sleeve is installed in the damping seat with a large clearance fit; an oil film is formed between the damping seat and the bearing sleeve after oil is filled;
[0010] The bearing cover is fixed on the damping seat to press the bearing; and countersunk holes are respectively provided at the center of the bottom surface of the bearing cover and the center of the inner side of the bottom end of the damping seat, and skeleton oil seals are respectively installed in the countersunk holes; the oil supply and return oil circuits provide lubricating oil to the bearing and the oil film.
[0011] Furthermore, the squeeze film damper also includes a limit member; a plurality of sink holes are provided at intervals on the inner surface of the bottom end of the damping seat below the bearing sleeve, and an upper sink hole opposite to the sink hole is provided on the bottom surface of the bearing sleeve, and the two ends of the limit member are respectively installed on the upper sink hole and the lower sink hole.
[0012] Furthermore, the limiting member is a spring, a pin or a stop.
[0013] Furthermore, the pressure cover is fixed on the damping seat and presses the bearing pressure cover.
[0014] Furthermore, the squeeze film damper also includes a sealing ring; a first sealing groove is provided on the bottom surface of the pressure cover above the bearing pressure cover, and second sealing grooves are respectively provided at the upper and lower ends of the outer circle of the bearing sleeve; the sealing rings are respectively installed in the first sealing groove and the second sealing groove.
[0015] Furthermore, the oil supply and return oil circuit includes a first oil supply port, a second oil supply port, a third oil supply port, a first oil return port, a second oil return port and a third oil return port; the first oil supply port is arranged on the bearing cover for supplying oil to the upper bearing; the second oil supply port is arranged in the middle of the outer circle of the damping seat, for supplying oil to between the damping seat and the bearing sleeve to form the oil film; the third oil supply port and the first oil return port are respectively arranged at the bottom end of the damping seat, the third oil supply port is used to supply oil to the bearing below, and the first oil return port is used to return oil to the upper and lower bearings; the second oil return port and the third oil return port are arranged in the upper and lower parts of the outer circle of the damping seat, and the two second sealing grooves are located between the second oil return port and the third oil return port for returning oil to the oil film.
[0016] Furthermore, the damping seat is an integrated structure in the shape of a hollow cylinder, or a split structure consisting of an outer circular structure and a bottom mounting seat.
[0017] Furthermore, the bearing sleeve is a multi-layer cavity structure or a single-layer cavity structure.
[0018] Furthermore, the damping particles of different diameters and materials are filled in different cavities of the bearing sleeve.
[0019] Furthermore, the inner center of the bottom end of the damping seat has a countersunk hole, and the lower part of the skeleton oil seal is installed in the countersunk hole to seal the bottom end of the damping seat; the center of the lower end face of the bearing pressure cover has a countersunk hole to install the skeleton oil seal to seal the top end of the squeeze oil film damper.
[0020] Beneficial effects of the utility model:
[0021] The vertical rotor overspeed tester of the utility model uses a composite squeeze film damper that combines particle damping vibration reduction and squeeze film vibration reduction. Through the dual energy consumption effects of particle collision energy consumption and squeeze film energy consumption, the vibration reduction effect can be greatly improved, thereby solving the problems of "bistable jump" and "locking" caused by excessive inner ring vibration amplitude of the squeeze film damper under high frequency and large amplitude working conditions.
[0022] The utility model uses damping particles filled in the bearing sleeve to reduce the amplitude of the bearing sleeve after consuming energy through particle collision when the amplitude of the inner ring is too large, thereby effectively preventing the squeeze film damper from causing "bistable jump" and "locking" problems due to excessive vibration amplitude of the inner ring.
[0023] The utility model ensures that the squeeze film damper can be designed independently through the upper and lower skeleton oil seals and the oil supply ports and the oil return ports, is not restricted by the structure of the bearings at the shaft support, and can be designed into a standardized series of products.
[0024] The squeeze film damper of the utility model can be separated from the lubrication structure in the drive device of the vertical rotor overspeed tester through an independent sealing structure and oil supply and return oil circuits, thereby avoiding oil leakage during installation and removal of the squeeze film damper and facilitating installation and removal. BRIEF DESCRIPTION OF THE DRAWINGS
[0025] Figure 1 The utility model is a structural schematic diagram of a composite squeeze film damper for a vertical rotor overspeed tester.
[0026] Among them: 1-rotating shaft, 2-bearing pressure cover, 2.1-first oil supply port, 3-pressure cover, 4-damping seat, 4.1-second oil supply port, 4.2-third oil supply port, 4.3-first oil return port, 4.4-second oil return port, 4.5-third oil return port, 5-bearing sleeve, 6-damping particles, 7-sealing ring, 8-spring, 9-skeleton oil seal, 10-bearing, 11-retaining ring. DETAILED DESCRIPTION
[0027] The following embodiments are used to further describe the specific embodiments of the present invention in conjunction with the accompanying drawings and examples. The following embodiments are only used to illustrate the present invention, but are not intended to limit the scope of the present invention.
[0028] Terms such as "upper," "lower," "left," "right," "inner," "outer," "front," "back," "head," and "tail" in this application are based on the directions or positions shown in the accompanying drawings. The corresponding positions may vary depending on the drawings, and should not be construed as limiting the scope of protection.
[0029] In this utility model, the terms "installed," "connected," "connected," "connected," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, integral connection, mechanical connection, electrical connection, or mutual communication. They can also refer to direct connection or indirect connection through an intermediate medium. They can also refer to internal communication between two components or interaction between two components. For those skilled in the art, the specific meanings of the above terms in this utility model can be understood according to specific circumstances.
[0030] This embodiment describes a composite squeeze film damper for a vertical rotor overspeed tester, which organically combines particle damping vibration reduction and squeeze film vibration reduction to form a composite squeeze film damper.
[0031] like Figure 1 As shown, the squeeze film damper is mounted on the rotating shaft 1 of the vertical rotor overspeed tester, and includes a bearing gland 2, a gland 3, a damping seat 4, a bearing sleeve 5, damping particles 6, a spring 8, a skeleton oil seal 9, a bearing 10, and a retaining ring 11.
[0032] In the bearing sleeve 5, two bearings 10 are mounted on the upper and lower ends of a retaining ring 11 through a transition fit with the bearing sleeve 5. The bearing sleeve 5 is a circular ring structure with either a multi-layer or single-layer cavity structure, which is used to fill damping particles 6. Different cavities can be filled with damping particles 6 of different diameters and materials. Damping particles 6 can be metallic or non-metallic particles. The size and filling rate of damping particles 6 are determined by the natural frequency and mass distribution of the shaft system.
[0033] The bearing sleeve 5 is installed in the damping seat 4 through a large clearance fit. The bearing sleeve 5 serves as the inner ring of the damper and an oil film is formed between the inner hole of the damping seat 4 and the oil is filled.
[0034] The damping seat 4 of this embodiment is an integrated structure in the shape of a hollow cylinder, with an open top and a stepped bottom, and a center hole in the center that matches the rotating shaft 1. A countersunk hole is provided at the center of the inner side of the bottom end of the damping seat 4, and the lower part of the skeleton oil seal 9 is installed in this countersunk hole to seal the gap between the rotating shaft 1 and the damping seat 4, thereby sealing the bottom end of the damping seat 4 to prevent lubricating oil from leaking from the bottom end of the damping seat 4 when the rotating shaft 1 rotates. The damping seat 4 can also adopt a split structure, that is, it consists of an outer cylindrical structure and a bottom mounting seat. The skeleton oil seal 9 and spring 8 are installed through the bottom mounting seat, and the skeleton oil seal 9 and spring 8 are connected to the bottom of the damping seat 4 by screws. The bearing 10 below is placed on the skeleton oil seal 9. The damping seat 4, below the bearing sleeve 5, has multiple spaced-apart countersunk holes on its bottom inner surface. Opposite to these holes is an upper countersunk hole on the bottom surface of the bearing sleeve 5. The upper and lower ends of a spring 8 are mounted in the upper and lower countersunk holes, respectively, to restrict circumferential rotation of the bearing sleeve 5, forcing it to move only in translation to squeeze the oil film. Alternatively, the spring 8 can be replaced with a pin or stop to limit circumferential rotation of the bearing sleeve 5. Mounting interfaces can be provided on the upper and lower end surfaces or outer circumference of the damping seat 4 for connecting it to the drive unit of the vertical rotor overspeed tester.
[0035] The bearing gland 2 is pressed against the bearing 10, the bearing sleeve 5, and the upper end surface of the damping seat 4. It is fixed to the bearing sleeve 5 with screws. When the bearing sleeve 5 vibrates, the bearing gland 2 vibrates with it. The bearing 10 is fixed to the bearing sleeve 5 by the retaining ring 11 and the bearing gland 2. The gland 3 is fixed to the damping seat 4 with screws and presses the bearing gland 2 tightly to prevent it from moving up and down.
[0036] The outer circle of the bearing cover 2 of this embodiment has an outwardly extending pressure plate for pressing the bearing sleeve 5 and the damping seat 4. The bottom end of the outer circle presses the upper bearing 10. The center of the inner side of the bearing cover 2 has a center hole that matches the rotating shaft 1. The center of the lower end surface of the bearing cover 2 is also provided with a countersunk hole for installing a skeleton oil seal 9. The oil seal closes the gap between the rotating shaft 1 and the bearing cover 2 to achieve sealing at the top of the damper to prevent lubricating oil from leaking from the top of the damping seat 4 when the rotating shaft 1 rotates. The bearing cover 2 with the skeleton oil seal 9 axially positions the bearing 10. The cover 3 of this embodiment can be a hollow circle with an L-shaped cross-section.
[0037] The squeeze film damper of this embodiment has separate oil supply and return oil circuits and seals, and can be installed independently of the tester drive device.
[0038] The oil supply and return oil circuit of the squeeze film damper: a first oil supply port 2.1 is provided on the bearing cover 2, which is used to supply lubricating oil to the upper bearing 10. A second oil supply port 4.1 is provided in the middle of the outer circle of the damping seat 4, which is used to supply lubricating oil between the damping seat 4 and the bearing sleeve 5 to form an oil film. A third oil supply port 4.2 and a first oil return port 4.3 are provided at the bottom end of the damping seat 4. The third oil supply port 4.2 is used to supply lubricating oil to the lower bearing 10, and the first oil return port 4.3 is used for returning oil to the two bearings 10. It is an L-shaped oil return port, and its horizontal opening is located on the side of the damping seat 4, which can slow down the oil return speed of the bearing 10 to ensure the lubrication of the bearing 10. A second oil return port 4.4 and a third oil return port 4.5 are provided on the upper and lower parts of the outer circle of the damping seat 4 respectively, which are used for oil film return.
[0039] The squeeze film damper's sealing structure includes a first sealing groove on the bottom surface of the gland 3 above the bearing gland 2, with a sealing ring 7 placed in the first sealing groove to prevent lubricating oil leakage from the squeeze film damper. Second sealing grooves are provided at the upper and lower ends of the outer circumference of the bearing sleeve 5, respectively, and the two second sealing grooves are located between the second oil return port 4.4 and the third oil return port 4.5. The sealing ring 7 is placed in the second sealing groove. When the bearing sleeve 5 is stationary, the oil film is sealed by the sealing ring 7. When the bearing sleeve 5 (i.e., the damper inner ring) vibrates, the oil film is squeezed and can flow out of the sealing ring 7 to form a flowing oil film. Preferably, the sealing ring 7 is an O-ring to meet both dynamic and static sealing requirements.
[0040] When the squeeze film damper is installed and in use, the rotating shaft 1 of the vertical rotor overspeed tester passes directly through the inner bore of the bearing 10. When the rotating shaft 1 rotates at high speed, the bearing sleeve 5 vibrates. This vibration squeezes the oil film, dissipating the oil film's reaction force. Under this squeeze, the oil film overflows from the sealing ring 7 and returns to the second and third oil return ports 4.4 and 4.5. Simultaneously, inelastic collisions and frictional motions between the damping particles 6 within the bearing sleeve 5 and between the damping particles 6 and the cavity wall dissipate energy, significantly reducing the vibration amplitude of the bearing sleeve 5, i.e., the inner ring of the squeeze film damper. When the rotating shaft 1 rotates at high speed, oil is supplied to the upper and lower bearings 10 through the first oil supply port 2.1 on the bearing gland 2 and the third oil supply port 4.2 on the damping seat 4, and oil is returned through the first oil return port 4.3 on the damping seat 4. This embodiment significantly improves the vibration damping effect of the entire squeeze film damper by dissipating the energy of high-frequency particle collisions and the squeeze film's reaction force, reducing the vibration amplitude of the rotating shaft 1.
[0041] Although the principles of the present invention have been described in detail above in conjunction with the preferred embodiments of the present invention, those skilled in the art should understand that the above embodiments are merely illustrative of the implementation of the present invention and are not intended to limit the scope of the present invention. The details in the embodiments do not constitute a limitation on the scope of the present invention. Without departing from the spirit and scope of the present invention, any obvious changes such as equivalent transformations and simple substitutions based on the technical solutions of the present invention fall within the scope of protection of the present invention.
Claims
1. A composite squeeze film damper for a vertical rotor overspeed tester, characterized in that: The squeeze film damper comprises a bearing gland (2), a damping seat (4), a bearing sleeve (5), damping particles (6), a bearing (10), a retaining ring (11) and an oil supply and return oil passage; The two bearings (10) in the bearing sleeve (5) are respectively placed at the upper and lower ends of the retaining ring (11) and connected to the bearing sleeve (5); the bearing sleeve (5) is a cavity structure, and the inner cavity is used to fill the damping particles (6); the bearing sleeve (5) is installed in the damping seat (4) through a large clearance fit; an oil film is formed between the damping seat (4) and the bearing sleeve (5) after oil is filled; The bearing pressure cover (2) is fixed on the damping seat (4) to press the bearing (10); and countersunk holes are respectively provided at the center of the bottom surface of the bearing pressure cover (2) and the center of the inner side of the bottom end of the damping seat (4), and skeleton oil seals (9) are respectively installed in the countersunk holes; the oil supply and return oil circuit provides lubricating oil to the bearing (10) and the oil film.
2. The composite squeeze film damper for a vertical rotor overspeed tester according to claim 1, characterized in that: The squeeze film damper also includes a limiting member; a plurality of sink holes are provided at intervals on the inner surface of the bottom end of the damping seat (4) below the bearing sleeve (5); an upper sink hole opposite to the sink hole is provided on the bottom surface of the bearing sleeve (5); and two ends of the limiting member are respectively installed in the upper sink hole and the lower sink hole.
3. The composite squeeze film damper for a vertical rotor overspeed tester according to claim 2, characterized in that: The limiting member is a spring (8) or a pin or a stop.
4. The composite squeeze film damper for a vertical rotor overspeed tester according to claim 1, characterized in that: The pressure cover (3) is fixed on the damping seat (4) and presses the bearing pressure cover (2).
5. The composite squeeze film damper for a vertical rotor overspeed tester according to claim 4, characterized in that: The squeeze film damper further comprises a sealing ring (7); a first sealing groove is provided on the bottom surface of the pressure cover (3) above the bearing pressure cover (2); and second sealing grooves are respectively provided at the upper and lower ends of the outer circle of the bearing sleeve (5); and the sealing ring (7) is respectively installed in the first sealing groove and the second sealing groove.
6. The composite squeeze film damper for a vertical rotor overspeed tester according to claim 5, characterized in that: The oil supply and return oil circuit comprises a first oil supply port (2.1), a second oil supply port (4.1), a third oil supply port (4.2), a first oil return port (4.3), a second oil return port (4.4) and a third oil return port (4.5); the first oil supply port (2.1) is arranged on the bearing cover (2) and is used to supply oil to the upper bearing (10); the second oil supply port (4.1) is arranged in the middle of the outer circle of the damping seat (4) and is used to supply oil between the damping seat (4) and the bearing sleeve (5) to form the oil film; the third oil supply port (4.2) is provided on the bearing cover (2) and is used to supply oil to the upper bearing (10); the second oil supply port (4.1) is provided in the middle of the outer circle of the damping seat (4) and is used to supply oil to the space between the damping seat (4) and the bearing sleeve (5) to form the oil film; the third oil supply port (4.3) is provided on the bearing cover (2) and is used to supply oil to the upper bearing (10); the second oil supply port (4.1) is provided in the middle of the outer circle of the damping seat (4) and is used to supply oil to the space between the damping seat (4) and the bearing sleeve (5) to form the oil film; the third oil supply port (4.2) is provided on the bearing cover (2) and is used to supply oil to the upper bearing (10); the third oil supply port (4.3) is provided on the bearing cover (2) and is used to supply oil to the upper bearing (10); the third oil supply port (4.1 ... The third oil supply port (4.2) and the first oil return port (4.3) are respectively arranged at the bottom end of the damping seat (4); the third oil supply port (4.2) is used to supply oil to the bearing (10) below, and the first oil return port (4.3) is used to return oil to the upper and lower bearings (10); the second oil return port (4.4) and the third oil return port (4.5) are arranged at the upper and lower parts of the outer circle of the damping seat (4), and the two second sealing grooves are located between the second oil return port (4.4) and the third oil return port (4.5) for the oil film return.
7. The composite squeeze film damper for a vertical rotor overspeed tester according to claim 1, characterized in that: The damping seat (4) is an integral structure in the shape of a hollow cylinder, or a split structure consisting of an outer circular structure and a bottom mounting seat.
8. The composite squeeze film damper for a vertical rotor overspeed tester according to claim 1, characterized in that: The bearing sleeve (5) is a multi-layer cavity structure or a single-layer cavity structure.
9. The composite squeeze film damper for a vertical rotor overspeed tester according to claim 8, characterized in that: The damping particles (6) of different diameters and different materials are filled in different cavities of the bearing sleeve (5).
10. The composite squeeze film damper for a vertical rotor overspeed tester according to claim 1, characterized in that: The damping seat (4) has a countersunk hole at the inner center of the bottom end, and the lower part of the skeleton oil seal (9) is installed in the countersunk hole to seal the bottom end of the damping seat (4); the bearing pressure cover (2) has a countersunk hole at the center of the lower end surface to install the skeleton oil seal (9) to seal the top end of the squeeze film damper.