Composite extrusion oil film damper

Abstract

The application discloses a composite extrusion oil film damper, which comprises a damper inner ring, a damper outer ring, a radial relative movement of the two, an oil storage cavity, a circumferential gap between the damper outer ring and the damper inner ring in the circumferential direction of the two, at least one throttle channel of the Tesla valve type between the outer ring end and the inner ring end, the positive inlet of the throttle channel being communicated with the circumferential gap, and the oil storage cavity comprising the circumferential gap and the at least one throttle channel. The damping coefficient generated by extruding the circumferential oil film and the damping coefficient generated by the positive flow of the oil in the throttle channel are synergistically superimposed to form the overall damping coefficient, the damping effect is better, and the oil between the inner ring end and the outer ring end can flow back to the circumferential gap in the reverse direction from the throttle channel, the cavitation problem of the circumferential oil film is relieved, and internal oil circulation is formed. Therefore, the application does not need to additionally set an external oil supply structure, the structure size is small, and the application range is wider.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of rotary machinery, in particular, to a composite squeeze film damper. BACKGROUND

[0002] Squeeze film dampers are widely used in rotor systems of aviation, marine and chemical production industries, such as aviation turbofan engines, marine gas turbines and centrifugal compressors in chemical industry, and are important vibration reduction and frequency modulation devices for rotor systems. The working mechanism is that the squeeze film damper squeezes the oil film under the driving of the rotor, and the oil film provides damping in the deformation process, thereby producing a damping effect on the rotor system.

[0003] However, in the prior art, the squeeze film damper is mainly designed for installation on a carrier or an aviation system, and has a large structure size and requires a special external oil supply system, which is difficult to apply to rotary machinery in special working environments, such as shaft systems of downhole turbine engines. SUMMARY

[0004] The purpose of the present application is to provide a composite squeeze film damper to solve the technical problem that the current squeeze film damper has a large structure size and requires a special external oil supply system, which is difficult to apply to rotary machinery in special working environments.

[0005] The above-mentioned purpose of the present application can be achieved by using the following technical solutions:

[0006] The present application provides a composite squeeze film damper, comprising: a damper inner ring, one end of which extends inwardly along its radial direction to form an inner ring end portion; a damper outer ring, which is sleeved on the damper inner ring, one end of the damper outer ring extending inwardly along its radial direction to form an outer ring end portion, the damper inner ring and the damper outer ring being arranged to be relatively movable in the radial direction of both; an oil storage cavity, the damper outer ring and the damper inner ring having a circumferential gap in the circumferential direction of both, the outer ring end portion and the inner ring end portion having at least one throttling passage of Tesla valve type, the forward inlet of the throttling passage being in communication with the circumferential gap, the oil storage cavity comprising the circumferential gap and at least one throttling passage.

[0007] In an embodiment of the present application, the inner ring outer end surface of the inner ring end portion is arranged opposite to the outer ring inner end surface of the outer ring end portion, and the inner ring outer end surface and the outer ring inner end surface are in sealing sliding contact.

[0008] In an embodiment of the present application, the throttling passage is arranged on the outer ring inner end surface.

[0009] In an embodiment of the present application, the number of throttle channels is multiple, and the multiple throttle channels are arranged along the circumferential direction of the outer ring end portion.

[0010] In an embodiment of the present application, the throttle channel comprises multiple throttle units arranged in series, and the multiple throttle units are alternately arranged on both sides of an extension direction, and the extension direction is arranged obliquely relative to the radial direction of the circumferential gap.

[0011] In an embodiment of the present application, multiple elastic structures are arranged along the circumferential direction of the circumferential gap, and the multiple elastic structures abut between the inner circumferential surface of the damper outer ring and the outer circumferential surface of the damper inner ring, and the multiple elastic structures divide the circumferential gap into multiple oil cavity units, and the multiple oil cavity units are connected with the multiple throttle channels.

[0012] In an embodiment of the present application, the elastic structure is a spring, and the spring is arranged along the radial direction of the circumferential gap.

[0013] In an embodiment of the present application, the oil storage cavity further comprises an oil storage groove, and the oil storage groove is located between the outer ring end portion and the inner ring end portion and is connected with the reverse inlet of the throttle channel, and the outer ring end portion and the inner ring end portion are further provided with an inner partition structure and an outer partition structure, and the oil storage groove is separated from the external environment by the inner partition structure, and the oil storage groove is separated from the circumferential gap by the outer partition structure.

[0014] In an embodiment of the present application, the composite extrusion oil film damper further comprises an end cover, and the end cover is fixed to one end of the damper outer ring away from the inner ring end portion, and the damper inner ring is limited between the end cover and the outer ring end portion in the axial direction, and the damper inner ring and the end cover, the inner ring end portion and the outer ring end portion, and the end cover and the damper outer ring are all provided with sealing structures.

[0015] In an embodiment of the present application, a sealing ring is arranged between the end cover and the damper outer ring.

[0016] In an embodiment of the present application, a plurality of first sealing grooves are arranged along the circumferential direction of the end of the damper inner ring facing the end cover, and the plurality of first sealing grooves are arranged along the radial direction of the damper inner ring.

[0017] In an embodiment of the present application, a plurality of second sealing grooves are arranged along the circumferential direction of the end of the inner ring end portion facing the outer ring end portion, and the plurality of second sealing grooves are arranged along the radial direction of the damper inner ring.

[0018] The characteristics and advantages of the present application are:

[0019] The composite extrusion oil film damper of the application, when the outer ring and the inner ring of the damper are relatively moved in the radial direction of the two due to the vibration of the rotor system, the circumferential oil film formed by the oil liquid in the circumferential gap is extruded to form a certain damping coefficient; by setting the throttling channel of Tesla type connected with the circumferential gap through the positive inlet between the end of the inner ring and the end of the outer ring, the oil liquid in the circumferential gap flows into the throttling channel from the positive inlet, so that the throttling effect generated by the positive flow of the oil liquid in the throttling channel forms a certain damping coefficient; thereby the damping coefficients of the two are cooperatively superimposed to form the overall damping coefficient, the damping effect is better, and the oil liquid between the end of the inner ring and the end of the outer ring can also flow back to the circumferential gap in the reverse direction from the throttling channel smoothly, the cavitation problem of the circumferential oil film is relieved and the internal oil liquid circulation is formed, therefore, the application does not need to additionally set an external oil supply structure, the structure size is small, and the application range is wider. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions in the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained from these drawings without creative labor.

[0021] Figure 1 It is a longitudinal section view of the composite extrusion oil film damper in the application.

[0022] Figure 2 It is a structure schematic view of the oil storage cavity of the composite extrusion oil film damper in the application.

[0023] Figure 3 It is a structure schematic view of the throttling channel in the application.

[0024] Figure 4 It is a longitudinal section view of the damper outer ring in the application.

[0025] Figure 5 It is a transverse section view of the composite extrusion oil film damper in the application.

[0026] In the drawings:

[0027] 1, inner ring of damper; 11, end of inner ring; 12, first sealing groove; 13, second sealing groove; 14, oil return hole; 15, elastic rubber valve; 16, central hole of inner ring; 17, outer end surface of inner ring; 2, outer ring of damper; 21, end of outer ring; 22, inner partition structure; 23, outer partition structure; 24, annular channel; 25, central hole of outer ring; 26, inner end surface of outer ring; 3, oil storage cavity; 31, circumferential gap; 32, throttling channel; 321, forward inlet; 322, reverse inlet; 323, throttling unit; 324, inclined channel; 325, curved channel; 33, oil storage groove; 4, elastic structure; 41, limiting groove; 5, end cover; 51, sealing ring. DETAILED DESCRIPTION

[0028] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0029] As shown in Figure 1 and Figure 2 The present application provides a composite extrusion oil film damper, comprising: an inner ring of damper 1, one end of which extends inward along its radial direction R to form an end of inner ring 11; an outer ring of damper 2, which is sleeved on the inner ring of damper 1, one end of the outer ring of damper 2 extending inward along its radial direction R to form an end of outer ring 21, the inner ring of damper 1 and the outer ring of damper 2 being arranged to be relatively movable in the radial direction R; an oil storage cavity 3, the outer ring of damper 2 and the inner ring of damper 1 having a circumferential gap 31 in the circumferential direction, the end of outer ring 21 and the end of inner ring 11 having at least one throttling channel 32 of Tesla valve type, the forward inlet 321 of the throttling channel 32 being in communication with the circumferential gap 31, the oil storage cavity 3 comprising the circumferential gap 31 and the at least one throttling channel 32.

[0030] In the composite extrusion oil film damper of the present invention, when the outer ring 2 and the inner ring 1 of the damper move relative to each other in the radial direction R due to the vibration of the rotor system, the circumferential oil film formed by the oil in the circumferential gap 31 is compressed, forming a certain damping coefficient. By setting a Tesla-type throttling channel 32 between the inner ring end 11 and the outer ring end 21 and connecting it to the circumferential gap 31, the oil in the circumferential gap 31 flows into the throttling channel 32 from the positive inlet 321, so that the throttling effect generated by the positive flow of the oil in the throttling channel 32 forms a certain damping coefficient. Thus, the damping coefficient is synergistically superimposed to form the overall damping coefficient, resulting in better damping effect. Furthermore, the oil between the inner ring end 11 and the outer ring end 21 can also flow smoothly back from the throttling channel 32 to the circumferential gap 31 in the reverse direction, alleviating the cavitation problem of the circumferential oil film and forming an internal oil circulation. Therefore, the present invention does not require an additional external oil supply structure, has a small structural size, and a wider range of applications.

[0031] Specifically, the inner ring end 11 is provided with an inner ring center hole 16 for the shaft to pass through, and the outer ring end 21 is provided with an outer ring center hole 25 for the shaft to pass through. The number of throttling channels 32 is not specifically limited, and can be designed according to the required damping coefficient. There can be one, or multiple channels as in this embodiment. Multiple throttling channels 32 are arranged at intervals along the circumference of the outer ring end 21, so that when the rotor system vibrates in different directions and drives the damper outer ring 2 and damper inner ring 1 to move relative to each other in different radial directions R, the oil in the circumferential gap 31 can be squeezed into the corresponding throttling channel 32.

[0032] like Figure 2 As shown, in an embodiment of the present invention, the throttling channel 32 includes a plurality of throttling units 323 connected in series. The plurality of throttling units 323 are alternately arranged on both sides of an extending direction S, which is inclined relative to the radial direction R of the circumferential gap 31. By arranging the plurality of throttling units 323 of the throttling channel 32 inclined relative to the radial direction R of the circumferential gap 31, the oil flowing in the forward direction in the throttling channel 32 can push the oil in front after flowing out from the reverse inlet 322 of the throttling channel 32. This allows the oil in front to flow in better from the reverse inlet 322 of the throttling channel 32 on one side, thereby facilitating the return of oil to the circumferential gap 31 and further alleviating the cavitation problem of the circumferential oil film in the circumferential gap 31.

[0033] Combination Figure 3As shown, specifically, each throttling unit 323 includes a curved passage 325 and an inclined passage 324, two ends of the curved passage 325 are connected with the inclined passage 324, and the plurality of throttling units 323 are connected in series through the plurality of inclined passages 324. Among them, the number of throttling units 323 is not particularly limited, and can be designed according to the required damping coefficient and arrangement space. In the embodiment, the number of throttling units 323 of each throttling passage 32 is four. In addition, the specific shape and size of the curved passage, the angle and size of the inclination of the inclined passage, are not limited to the structure shown in the embodiment, and other size throttling passages of Tesla valve type in the prior art can also be used.

[0034] As shown in Figure 1 and Figure 2 shown, in the embodiment of the application, the oil storage cavity 3 further includes an oil storage groove 33, the oil storage groove 33 is located between the outer ring end portion 21 and the inner ring end portion 11 and is connected with the reverse inlet 322 of the throttling passage 32, and the outer ring end portion 21 and the inner ring end portion 11 are further provided with an inner separation structure 22 and an outer separation structure 23, the oil storage groove 33 is separated from the external environment through the inner separation structure 22, and the oil storage groove 33 is separated from the circumferential gap 31 through the outer separation structure 23. The oil flowing in the forward direction in the throttling passage 32 flows into the oil storage groove 33 from the reverse inlet 322, and the oil in the oil storage groove 33 flows into the throttling passage 32 from the reverse inlet 322 of the throttling passage 32, and finally flows back to the circumferential gap 31 in the reverse direction. By providing the inner separation structure 22, the oil in the oil storage groove 33 is prevented from leaking to the outside, and by providing the outer separation structure 23, the oil in the circumferential gap 31 is prevented from directly entering the oil storage groove 33 without throttling through the throttling passage 32.

[0035] As shown in Figure 1 , the inner ring outer end surface 17 of the inner ring end portion 11 is oppositely arranged with the outer ring inner end surface 26 of the outer ring end portion 21, and the inner ring outer end surface 17 and the outer ring inner end surface 26 are in sliding contact, that is, the inner ring outer end surface 17 and the outer ring inner end surface 26 are in close contact and can simultaneously adapt to the vibration of the rotor system and slide tangentially.

[0036] Specifically, by slotting on the inner ring outer end surface 17 and / or the outer ring inner end surface 26, a throttling passage 32, an oil storage groove 33, and an annular passage 24 for connecting the circumferential gap 31 with the throttling passage 32 are formed, wherein the cross-sectional shape of the annular passage 24 is the same as that of the circumferential gap 31. In the embodiment, in combination with Figure 4 shown, the throttling passage 32, the oil storage groove 33, and the annular passage 24 are all arranged on the outer ring inner end surface 26, the annular passage 24 and the oil storage groove 33 form the outer separation structure 23, and the oil storage groove 33 and the outer ring center hole 16 form the inner separation structure. In addition, in combination with Figure 2 and Figure 3As shown, the two sides of the throttling passage 32 are provided with passage separation structures separated from the oil storage groove 33, and the transition of the outer side of the passage separation structure facing the oil storage groove 33 is smooth, which facilitates the flow of oil in the oil storage groove 33.

[0037] As Figure 1 As shown, in the embodiment of the present application, the composite extrusion oil film damper further comprises an end cover 5 fixed to one end of the damper outer ring 2 away from the inner ring end portion 11, the damper inner ring 1 is limited between the end cover 5 and the outer ring end portion 21 in the axial direction Z, and sealing structures are provided between the damper inner ring 1 and the end cover 5, between the inner ring end portion 11 and the outer ring end portion 21, and between the end cover 5 and the damper outer ring 2. By setting the end cover 5 to close one end of the circumferential gap 31 away from the throttling passage 32, the oil storage cavity 3 is substantially a closed cavity structure, and the damper inner ring 1 is limited in the axial direction Z.

[0038] Specifically, the outer edge portion of the end cover 5 is connected to the outer edge portion of the damper outer ring 2 by laser welding. A sealing ring 51 is provided between the end cover 5 and the damper outer ring 2, and the sealing ring 51 is an O-shaped sealing ring. A plurality of first sealing grooves 12 are provided along the circumference of one end of the damper inner ring 1 facing the end cover 5, and the plurality of first sealing grooves 12 are spaced apart along the radial direction R of the damper inner ring 1. A plurality of second sealing grooves 13 are provided along the circumference of one end of the inner ring end portion 11 facing the outer ring end portion 21, and the plurality of second sealing grooves 13 are spaced apart along the radial direction R of the damper inner ring 1. The plurality of first sealing grooves 12 and the plurality of second sealing grooves 13 are equally spaced, and the number, width and spacing of the two are not specifically limited. In this embodiment, the first sealing groove 12 is two, and the number of the second sealing groove 13 is eight, and the width is 2mm.

[0039] In addition, an elastic rubber valve 15 is provided between the inner edge portion of the end cover 5 and the damper inner ring 1, and the damper inner ring 1 is provided with a return oil hole 14, one end of which is covered by the elastic rubber valve 15, and the other end of which extends to the inner ring outer end face 17 along the axial direction Z of the damper inner ring 1, so that the leaked oil between the end cover 5 and the damper inner ring 1 can be collected by the elastic rubber valve 15 and returned to the oil storage cavity 3 through the return oil hole 14, further ensuring that the oil in the composite extrusion oil film damper always circulates inside and does not leak to the outside environment, and does not need to be supplemented by an external oil supply structure due to oil leakage.

[0040] As Figure 1 and Figure 5As shown, in the embodiment of the present application, a plurality of elastic structures 4 are arranged in the circumferential gap 31 along the circumferential direction, and abut between the inner circumferential surface of the outer ring 2 and the outer circumferential surface of the inner ring 1. The elastic structures 4 elastically limit and support the inner ring 1 and the outer ring 2, provide a certain pre-tightening force when the inner ring 1 and the outer ring 2 are assembled, and divide the circumferential gap 31 into a plurality of oil cavity units, thereby inhibiting the oil film imbalance distribution phenomenon caused by the large amplitude whirling of the rotor in the damper, and further avoiding the nonlinear response of the rotor. The plurality of oil cavity units and the plurality of throttle channels 32 are in one-to-one correspondence and in communication, thereby facilitating the oil in each of the plurality of oil cavity units to flow into the corresponding throttle channel 32.

[0041] Specifically, the circumferential gap 31 and the annular channel 24 are provided with a plurality of limiting grooves 41 corresponding to each other, and the plurality of elastic structures 4 are limited in the plurality of limiting grooves 41. The number of elastic structures 4 is equal to the number of throttle channels 32, and the forward inlet 321 of each throttle channel 32 is located in the middle of the two adjacent elastic structures 4. In this embodiment, the number of elastic structures 4 and the number of throttle channels 32 are both six, and are uniformly arranged along the circumferential direction of the circumferential gap 31. The elastic structure 4 is a spring, and the spring is arranged along the radial direction R of the circumferential gap 31. The cross section of the spring is generally S-shaped. The material of the spring is 55SiMnB. The materials of the inner ring 1, the outer ring 2 and the end cover 5 can all be nodular cast iron.

[0042] The above only describes several embodiments of the present application, and those skilled in the art can make various modifications or changes to the embodiments of the present application according to the disclosed content of the application file without departing from the spirit and scope of the present application.

Claims

1. A compound squeeze film damper, characterized by, The composite squeeze oil film damper comprises: a damper inner ring, one end of which extends radially inward to form an inner ring end; a damper outer ring, which is sleeved on the damper inner ring, one end of the damper outer ring extending radially inward to form an outer ring end, the damper inner ring and the damper outer ring being arranged to be movable relative to each other in the radial direction of the two rings; an oil storage cavity, the damper outer ring and the damper inner ring having a circumferential gap in the circumferential direction of the two rings, the outer ring end and the inner ring end having at least one throttling passage of the Tesla valve type, the positive inlet of the throttling passage being in communication with the circumferential gap, the oil storage cavity comprising the circumferential gap and at least one throttling passage; a plurality of elastic structures are arranged in the circumferential gap in the circumferential direction, the plurality of elastic structures abutting between the inner circumferential surface of the damper outer ring and the outer circumferential surface of the damper inner ring, and the plurality of elastic structures separating the circumferential gap into a plurality of oil cavity units, the plurality of oil cavity units being in communication with the plurality of throttling passages; the oil storage cavity further comprises an oil storage groove, the oil storage groove being located between the outer ring end and the inner ring end and being in communication with the reverse inlet of the throttling passage, the outer ring end and the inner ring end further being provided with an inner separation structure and an outer separation structure, the oil storage groove being separated from the external environment by the inner separation structure, and the oil storage groove being separated from the circumferential gap by the outer separation structure.

2. The composite squeeze oil film damper according to claim 1, wherein the inner ring outer end surface of the inner ring end is arranged opposite the outer ring inner end surface of the outer ring end, and the inner ring outer end surface and the outer ring inner end surface are in sealing sliding contact.

3. The composite squeeze oil film damper according to claim 2, wherein the throttling passage is provided on the outer ring inner end surface.

4. The composite squeeze oil film damper according to claim 1, wherein the number of throttling passages is a plurality, and the plurality of throttling passages are arranged in the circumferential direction of the outer ring end.

5. The composite squeeze oil film damper according to claim 4, wherein the throttling passage comprises a plurality of throttling units connected in series, and the plurality of throttling units are alternately arranged on both sides of an extension direction, and the extension direction is inclined relative to the radial direction of the circumferential gap.

6. The composite squeeze oil film damper according to claim 5, wherein the elastic structure is a spring, and the spring is arranged in the radial direction of the circumferential gap.

7. The composite squeeze oil film damper according to claim 1, wherein the composite squeeze oil film damper further comprises an end cover, the end cover being fixed to one end of the damper outer ring away from the inner ring end, the damper inner ring being limited in the axial direction between the end cover and the outer ring end, and the damper inner ring and the end cover, the inner ring end and the outer ring end, and the end cover and the damper outer ring are all provided with sealing structures.

8. The composite squeeze oil film damper according to claim 7, wherein A sealing ring is arranged between the end cover and the outer ring of the damper.

9. The compound squeeze film damper of claim 7, wherein, A plurality of first sealing grooves are circumferentially arranged on an end of the inner ring of the damper facing the end cover, and the first sealing grooves are radially spaced apart along the inner ring of the damper.

10. The compound squeeze film damper of claim 7, wherein, A plurality of second sealing grooves are circumferentially arranged on an end of the inner ring of the damper facing the end cover, and the second sealing grooves are radially spaced apart along the inner ring of the damper.

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