An interface structure between a centrifugal compressor and a diffuser

Abstract

The present invention discloses an interface structure between a centrifugal compressor and a diffuser, which relates to the technical field of centrifugal compressors. It includes a diffuser and an impeller rotatably arranged on its axis. There is a connecting piece located between the diffuser and the impeller, on which a plurality of contact rollers are arranged in a circumferential array. The connecting piece includes: an outer wall surface for guiding air flow towards the diffuser; an inner wall surface opposite to the impeller, and the inner wall surface and the outer periphery of the impeller enclose an annular oil passage for accommodating lubricating oil. In the interface structure between the centrifugal compressor and the diffuser, when the impeller rotates at a high speed, the flow rate of the lubricating oil increases, and a lubricating oil film with a certain thickness is formed between the impeller and the inner wall surface, which has a buffering effect on the oscillation of the impeller. When the speed of the impeller is too fast, the lubricating oil in the supply cavity is squeezed into the annular oil passage for automatic replenishment to maintain the thickness of the oil film.

Description

Technical Field

[0001] The present invention relates to the technical field of centrifugal compressors, and more particularly to an interface structure between a centrifugal compressor and a diffuser. Background Art

[0002] The outlet of a centrifugal compressor is usually connected to the inlet of a diffuser. Generally, an impeller operating as a rotor is coaxially sleeved inside the diffuser. Since the impeller rotates relative to the diffuser, high-frequency oscillations generated during the high-speed rotation of the impeller will cause friction with the diffuser. At this time, it is necessary to inject a part of lubricating liquid to reduce the friction force.

[0003] Combined with the authorized (announcement) number CN104895807B and the authorized (announcement) date April 3, 2018, a centrifugal compressor is disclosed, including: a motor, a support housing, a second transmission shaft, and a diffuser. The motor has a motor housing and a first transmission shaft. A sliding bearing is sleeved outside the part of the first transmission shaft located inside the support housing. A roller bearing is sleeved outside the part of the second transmission shaft located inside the support housing. The diffuser includes a diffuser housing, a partition plate, and an impeller. The peripheral wall of the part of the second transmission shaft extending into the diffuser is formed as a non-circular shape, the central hole of the impeller is formed as a non-circular hole, and a floating seal is provided on the impeller.

[0004] However, in the prior art including the above patent, the part of the second transmission shaft located inside the support housing can be sequentially sleeved with two roller bearings along the length direction. In this way, compared with the existing sliding bearing, the amount of lubricating oil required for the bearing can be effectively reduced. However, after the amount of lubricating oil is reduced, the oil film thickness decreases, and the roller is prone to further thinning of the oil film during high-speed rotation, affecting the lubrication effect. Summary of the Invention

[0005] The purpose of the present invention is to provide an interface structure between a centrifugal compressor and a diffuser to solve the above problems.

[0006] To achieve the above purpose, the present invention provides the following technical solution: An interface structure between a centrifugal compressor and a diffuser, including a diffuser and an impeller rotatably provided on its axis, including a connecting member located between the diffuser and the impeller, on which a plurality of contact rollers are circumferentially and arrayedly provided;

[0007] The connecting member includes:

[0008] An outer wall surface for guiding the air flow towards the diffuser;

[0009] An inner wall surface opposite to the impeller, and the inner wall surface and the outer periphery of the impeller enclose an annular oil passage for accommodating lubricating oil;

[0010] Wherein, the connecting member has a contracted state in which the distance between the inner wall surface and the outer wall surface is shortened.

[0011] Preferably, a predetermined gap is maintained between the side surface of the contact roller and the outer side of the impeller, and the contact roller rotates with the impeller to form a vortex of the lubricating oil.

[0012] Preferably, it further includes a stabilizing roller rotatably arranged on the connecting piece and synchronously moving with the contact roller.

[0013] Preferably, it further includes a sealing ring fixedly arranged on the impeller and a memory metal arranged in a circumferential array and movably arranged in the interval of the sealing ring, and the included angle between the memory metal and the annular oil passage is adjustable.

[0014] Preferably, a cutting piece pointing in the oil flow direction is fixedly arranged on the memory metal.

[0015] Preferably, a folding part is arranged on the inner wall surface of the connecting piece, and the included angle of the memory metal is the smallest when the distance between the folding parts is the smallest.

[0016] Preferably, the outer wall surface of the connecting piece and the end surface of the impeller are of a stepped structure, and a dial plate is arranged on the connecting piece.

[0017] Preferably, an arc surface is arranged on the outer wall surface of the connecting piece, and a channel with a decreasing inner diameter is formed between the arc surface and the dial plate.

[0018] Preferably, a heat-sensitive block is arranged at the first end of the dial plate close to the diffuser, and a protrusion for guiding the condensation is arranged at the second end opposite thereto.

[0019] Preferably, it further includes a transmission shaft for driving the impeller, and an adjustment unit for controlling the connecting piece is arranged thereon, and the adjustment unit includes an extension rod that moves radially along with the temperature change.

[0020] In the above technical solution, an interface structure between a centrifugal compressor and a diffuser provided by the present invention has the following beneficial effects: When the impeller rotates at a high speed, the flow rate of the lubricating oil increases, and a certain thickness of oil film formed between the impeller and the inner wall surface buffers the oscillation of the impeller. When the speed of the impeller is too fast, the lubricating oil in the supply cavity is squeezed into the annular oil passage for automatic replenishment to maintain the oil film thickness. Description of the Drawings

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required in the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

[0022] Figure 1Overall three - dimensional schematic diagram provided by the embodiment of the present invention;

[0023] Figure 2 Overall sectional structure schematic diagram provided by the embodiment of the present invention;

[0024] Figure 3 Schematic diagram of the connecting piece and the adjusting unit structure provided by the embodiment of the present invention;

[0025] Figure 4 Internal explosion structure schematic diagram provided by the embodiment of the present invention;

[0026] Figure 5 Schematic diagram of the diffuser chamber, impeller and transmission shaft structure provided by the embodiment of the present invention;

[0027] Figure 6 Provided by the embodiment of the present invention Figure 3 Enlarged schematic diagram of structure A in

[0028] Figure 7 Schematic diagram of the connecting piece and the contact roller structure provided by the embodiment of the present invention;

[0029] Figure 8 Schematic diagram of the folding part and the shape memory alloy structure provided by the embodiment of the present invention;

[0030] Figure 9 Schematic diagram of the shape memory alloy structure provided by the embodiment of the present invention;

[0031] Figure 10 Provided by the embodiment of the present invention Figure 2 Enlarged schematic diagram of structure B in

[0032] Explanation of reference numerals:

[0033] 1. Air inlet; 11. Impeller; 12. Contact roller; 13. Stabilizing roller; 14. Guide groove; 15. Limit block; 16. Transmission belt; 2. Diffuser chamber; 21. Diffuser; 22. Sealing ring; 23. Throat; 3. Housing; 4. Cooling channel; 5. Transmission shaft; 51. Heat conducting rod; 52. Sealed cavity; 53. Extension rod; 6. Oil inlet channel; 61. Control cavity; 62. Oil delivery channel; 63. Piston; 64. Spring; 7. Oil outlet channel; 8. Thrust bearing; 9. Connecting piece; 91. Dial plate; 92. Heat - sensitive block; 93. Protrusion; 94. Air port; 95. Arc surface; 96. Supply cavity; 97. Folding part; 98. Shape memory alloy; 981. Cutting piece; 982. Movable plate. Detailed implementation manners

[0034] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further introduced in detail below with reference to the accompanying drawings.

[0035] As shown Figures 1 - 10 in the figure, an interface structure between a centrifugal compressor and a diffuser includes a diffuser 21 and an impeller 11 rotatably arranged on its axis. It includes a connecting member 9 located between the diffuser 21 and the impeller 11, on which a plurality of contact rollers 12 are arranged in a circumferential array;

[0036] The connecting member 9 includes:

[0037] An outer wall surface for guiding the air flow towards the diffuser 21;

[0038] An inner wall surface opposite to the impeller 11, and an annular oil passage for accommodating lubricating oil is formed by enclosing the outside of the impeller 11;

[0039] Wherein, the connecting member 9 has a contracted state in which the distance between the inner wall surface and the outer wall surface is shortened.

[0040] Specifically, it further includes an air inlet 1 and a diffuser chamber 2 arranged at a corresponding position of the diffuser 21, and the diffuser chamber 2 is communicated with a cooling channel 4 to cool the air flow in the diffuser chamber 2. An oil inlet passage 6 and a control chamber 61 communicated with the oil inlet passage 6 are formed in the impeller 11. Among them, a piston 63 is movably arranged in the control chamber 61, and a spring 64 is arranged between the piston 63 and the port of the oil inlet passage 6 to maintain a predetermined distance.

[0041] Furthermore, taking Figure 5 the direction shown as a reference, during the assembly process, the connecting member 9 is first assembled into the diffuser 21, and then the impeller 11 is sleeved along the connecting member 9. The direction of sleeving the impeller 11 is opposite to the air inlet direction, so that the outer side surface of the impeller 11 is opposite to the inner wall surface of the connecting member 9.

[0042] Further, the impeller 11 rotates and sucks the gas from the air inlet 1, and diffuses the gas radially by the centrifugal force generated during high-speed rotation. During the gas diffusion process, the gas enters the diffuser 21 along the outer wall surface of the connecting member 9. During the rotation of the impeller 11, a centrifugal force is generated on the piston 63, so that the piston 63 moves radially and away from the port of the oil inlet passage 6, and the spring 64 contracts. Since the distance between the piston 63 and the port of the oil inlet passage 6 increases, the flow rate of the lubricating oil increases and enters the annular oil passage through the oil delivery passage 62. Automatically enter the annular oil passage under the state of high-speed rotation of the impeller 11. An oil film with a certain thickness formed by the lubricating oil between the impeller 11 and the inner wall surface relieves the oscillation generated under the high-speed rotation of the impeller 11, and the inner wall surface of the connecting member 9 will be washed by the lubricating oil with centrifugal force, so that the inner wall surface of the connecting member 9 approaches the outer wall surface. There is a supply chamber 96 filled with part of the lubricating oil between the inner wall surface and the outer wall surface of the connecting member 9, and the lubricating oil in the supply chamber 96 is squeezed into the annular oil passage for automatic replenishment to maintain the thickness of the oil film.

[0043] In the above-mentioned technology, when the impeller 11 rotates at a high speed, the flow rate of the lubricating oil increases, and a lubricating oil film with a certain thickness is formed between the impeller 11 and the inner wall surface, which buffers the oscillation of the impeller 11. When the speed of the impeller 11 is too fast, the lubricating oil in the supply chamber 96 is squeezed into the annular oil passage for automatic replenishment to maintain the thickness of the oil film.

[0044] As a further embodiment provided by the present invention, a predetermined gap is maintained between the side surface of the contact roller 12 and the outside of the impeller 11, and the contact roller 12 rotates with the impeller 11 to form a vortex of the lubricating oil.

[0045] Specifically, the end of the contact roller 12 facing the annular oil passage is a wide part, and the opposite end is a narrow part. The side surface of the contact roller 12 is an inclined surface parallel to the impeller 11, and the predetermined gap between the contact roller 12 and the impeller 11 is not greater than 1 mm to avoid oil leakage. When the impeller 11 rotates, the contact roller 12 is driven to rotate by the oil film. Since the contact roller 12 has a frustum-shaped structure, as Figure 7 shown in the structure, the side surface of the contact roller 12 will generate a shearing force on the oil film. Combining with the centrifugal force generated by the contact roller 12 on the attached oil film during rotation, the two act together to generate a vortex. A threaded guiding groove 14 is provided on the contact roller 12 to guide the oil flow. The vortex spreads in a spiral path away from the contact roller 12, that is, it flows from the narrow part to the wide part of the contact roller 12. Through this vortex, the leakage of the oil film at the narrow part of the contact roller 12 can be effectively reduced.

[0046] As still another embodiment provided by the present invention, it further includes a stabilizing roller 13 rotatably arranged on the connecting member 9 and synchronously moving with the contact roller 12.

[0047] Specifically, the stabilizing roller 13 is located at the outer periphery of the contact roller 12 in the radial direction, and the stabilizing roller 13 is vertically arranged at the contact part between the outer wall surface and the impeller 11. The contact surfaces of the stabilizing roller 13 and the contact roller 12 are parallel to each other, so that the stabilizing roller 13 can provide a supporting force perpendicular to the contact roller 12 to the contact roller 12.

[0048] Furthermore, a limit block 15 is fixedly arranged on the contact roller 12, and the limit block 15 is drivingly connected to the rotating shaft of the stabilizing roller 13 through a transmission belt 16, so that when the contact roller 12 rotates, it drives the stabilizing roller 13 to rotate synchronously in the same direction. At the closest point between the contact roller 12 and the stabilizing roller 13, the rotation directions of the contact roller 12 and the stabilizing roller 13 are opposite, and the oil flow moves from the vortex generated by the contact roller 12 to the stabilizing roller 13. Due to the opposite rotation directions and the narrow gap between the contact roller 12 and the stabilizing roller 13, the oil flow mainly flows along the wall surface at the above-mentioned closest point, and the deceleration of the wall surface near the viscous force is obvious. The wall surface close to the contact roller 12 and the stabilizing roller 13 is the inner layer. The fluid microgroups in the inner layer can obtain more momentum supplement from the outer layer through additional turbulent eddy viscosity force, so as to maintain non-backflow at a farther distance, further prevent leakage, and reduce the oil flow speed in the annular oil passage through the deceleration effect, offsetting part of the acceleration effect of the centrifugal force on the oil flow and avoiding the problem of oil film oscillation in the annular oil passage.

[0049] As yet another embodiment further provided by the present invention, it further includes a sealing ring 22 fixedly arranged on the impeller 11 and a shape memory alloy 98 arranged in a circumferential array and movably arranged in the intervals of the sealing ring 22, and the included angle between the shape memory alloy 98 and the annular oil passage is adjustable.

[0050] Specifically, the sealing ring 22 is a labyrinth sealing structure with a plurality of linearly arranged fixed intervals, and the shape memory alloy 98 is rotatably arranged in the intervals. When the oil speed in the annular oil passage is too fast, the shape memory alloy 98 is impacted by the oil flow and swings to form an included angle with the oil flow direction, so that the oil flow generates turbulence in the intervals, reducing the oil flow speed and providing support through the acting force of the turbulence on the sealing ring 22, further avoiding the problem of oil film oscillation. The impeller 11 rotates relative to the shape memory alloy 98, and the shape memory alloy 98 generates a breaking effect on the oil flow in the annular oil passage during the swinging process, avoiding the aggregation of coking residues in the oil flow.

[0051] As yet another embodiment further provided by the present invention, a cutting piece 981 pointing in the oil flow direction is fixedly arranged on the shape memory alloy 98.

[0052] Specifically, a folding part 97 is arranged on the inner wall surface of the connecting piece 9, and the included angle of the shape memory alloy 98 is the smallest when the distance between the folding parts 97 is the smallest. The shape memory alloy 98 further includes a movable plate 982. The two ends of the shape memory alloy 98 are respectively arranged on both sides of the folding part 97. When the distance between the folding parts 97 is the smallest, a plurality of shape memory alloys 98 are in a state of being connected end to end and overlapping each other, as Figure 8As shown in the figure. A distance is maintained between the inner wall surface and the outer wall surface of the folding part 97 through an inclined side wall. When the distance is shortened, the side wall swings from an inclined state to a horizontal state, and the outer wall moves away from the impeller 11, causing the folding part 97 to unfold. The shape memory metal 98 is pulled, and the shape memory metals 98 switch to a parallel state with each other, and the included angle with the annular oil passage increases. The movable plate 982 is driven and the bending angle between the movable plate 982 and the shape memory metal 98 becomes larger, causing the cutting piece 981 to extend along the bending direction and cut the coke deposits in the oil passage.

[0053] As yet another embodiment further provided by the present invention, the outer wall surface of the connecting member 9 and the end surface of the impeller 11 are of a stepped structure, and a deflector plate 91 is provided on the connecting member 9.

[0054] Specifically, the stepped structure is as Figure 5 shown, making the air flow direction consistent with the guiding direction of the connecting member 9, preventing the air flow from flowing back during the diffusion process in the diffuser chamber 2. And the deflector plate 91 is of an arc-shaped structure. The connecting part between the air inlet 1 and the diffuser chamber 2 is a pharyngeal orifice 23. The deflector plate 91 is located at the pharyngeal orifice 23 and divides the pharyngeal orifice 23 into a first channel close to the inner wall of the air inlet 1 and a second channel close to the connecting member 9. During the ventilation process, the air flow flows along the inner wall of the air inlet 1. Due to the shear force of the inner wall on the air flow, the speed of this part of the air flow is slower, and it enters the diffuser chamber 2 through the first channel along the inner wall. And the air flow in this part has a slower speed due to the lack of acceleration by the impeller 11, while the air flow in the second channel has a faster speed after being centrifugally accelerated by the impeller 11, resulting in a lower air pressure in the second channel. The end of the deflector plate 91 swings into the second channel, so that the air flow flowing along the inner wall is guided to the first channel and accelerated under the push of the air flow in the original first channel, further improving the diffusing effect and preventing the air flow at the boundary position from entering the diffuser chamber 2 without being fully accelerated.

[0055] As yet another embodiment further provided by the present invention, an arc surface 95 is provided on the outer wall surface of the connecting member 9, and a channel with a decreasing inner diameter is formed between the arc surface 95 and the deflector plate 91.

[0056] Specifically, a plurality of air ports 94 corresponding to the arc surface 95 are opened on the connecting member 9 for communicating the channel and the diffuser chamber 2. The air flow accelerates when flowing along the arc surface 95, generating a local low-pressure area on the arc surface 95. Combined with the end of the deflector plate 91 swinging into the second channel, the air flow flowing along the inner wall is guided to the first channel, so that a pushing force for pushing the connecting member 9 is provided when the air flow passes through the connecting member 9, preventing the connecting member 9 from slipping off under the action of the oil film during high-speed rotation.

[0057] As yet another embodiment further provided by the present invention, a heat-sensitive block 92 is provided at the first end of the deflector plate 91 close to the diffuser 21, and a protrusion 93 for guiding condensate is provided at the second end opposite thereto.

[0058] Specifically, since the inner diameter of the diffuser chamber 2 increases, the velocity of the air flow decreases within the diffuser chamber 2. The mechanical energy provided to the air flow by the operation of the impeller 11 is converted into heat energy, and the temperature within the diffuser chamber 2 rises. The throat 23 is directly connected to the diffuser chamber 2, causing the temperature of the heat-sensitive block 92 to rise under the influence of the temperature within the diffuser chamber 2. However, since a channel with a decreasing inner diameter is formed between the arc surface 95 and the baffle 91, the air flow within this channel maintains a high velocity under the action of the impeller 11. Therefore, the temperature inside this channel is relatively low, and there is a temperature difference on both sides of the baffle 91. As a result, the air flow passing through the arc surface 95 will come into contact with the baffle 91 at a higher temperature, and the water vapor within the air flow will condense on the side surface of the baffle 91 and slide down along the baffle 91 to the protrusion 93, where it condenses due to the protrusion 93 and forms dew. Then, it is weathered by the high-speed air flow and forms a cycle in the throat, reducing the probability of water vapor directly entering the diffuser chamber 2 and preventing the expansion of water vapor in the high-temperature diffuser chamber 2 from affecting the pressure stability within the diffuser chamber 2.

[0059] As yet another embodiment further provided by the present invention, it further includes a transmission shaft 5 for driving the impeller 11, and an adjustment unit for controlling the connecting member 9 is provided thereon. The adjustment unit includes an extension rod 53 that moves radially along with temperature changes.

[0060] Specifically, a thrust bearing 8 is provided on the transmission shaft 5, and an oil outlet channel 7 is provided on the thrust bearing 8. A plurality of sealed cavities 52 are arranged in a circumferential array on the transmission shaft 5. The sealed cavities 52 are filled with a gas that is significantly affected by thermal expansion and contraction. The extension rod 53 is slidably arranged within the sealed cavity 52. When the operating speed of the transmission shaft 5 is too fast and generates high heat, at this time, the temperature is transmitted to the sealed cavity 52 through the heat conduction rod 51 provided on the transmission shaft 5, causing the gas within the sealed cavity 52 to expand and push the extension rod 53. The extension rod 53 moves radially and presses against the inner wall surface of the connecting member 9, shortening the distance between the inner wall surface and the outer wall surface.

[0061] Working principle: During use, the impeller 11 rotates and sucks in gas from the air inlet 1, and diffuses the gas radially through the centrifugal force generated during high-speed rotation. During the diffusion process of the gas, it enters the diffuser 21 along the outer wall surface of the connecting member 9. During the rotation of the impeller 11, a centrifugal force is generated on the piston 63, causing the piston 63 to move radially and away from the port of the oil inlet passage 6. The spring 64 contracts. Since the distance between the piston 63 and the port of the oil inlet passage 6 increases, the flow rate of the lubricating oil increases and enters the annular oil passage through the oil delivery passage 62.

[0062] As the rotational speed of the impeller 11 increases, when the transmission shaft 5 runs too fast and generates high heat, at this time, the temperature is transmitted into the sealed cavity 52 through the heat conducting rod 51 provided on the transmission shaft 5, causing the gas in the sealed cavity 52 to expand and push against the extension rod 53. The extension rod 53 moves radially and presses against the inner wall surface of the connecting member 9, causing the distance between the inner wall surface and the outer wall surface to shorten. There is a supply cavity 96 with some lubricating oil between the inner wall surface and the outer wall surface of the connecting member 9. The lubricating oil in the supply cavity 96 is squeezed into the annular oil passage for automatic replenishment to maintain the oil film thickness.

[0063] When the impeller 11 rotates, the contact roller 12 is driven to rotate by the oil film. Since the contact roller 12 has a frustum-shaped structure, as Figure 7 shown in the structure, the side surface of the contact roller 12 will generate a shear force on the oil film. Combining with the centrifugal force generated by the contact roller 12 on the attached oil film during rotation, the two act together to generate a vortex. The contact roller 12 is provided with a spiral-shaped guiding groove 14 for guiding the oil flow. The vortex spreads along a spiral path away from the contact roller 12, that is, it flows from the narrow part to the wide part of the contact roller 12. Through this vortex, the leakage of the oil film at the narrow part of the contact roller 12 can be effectively reduced. Since the rotation directions are opposite and the gap between the contact roller 12 and the stable roller 13 is narrow, the oil flow mainly flows along the wall surface at the nearest point. The deceleration of the wall surface near the wall surface due to the viscous force is obvious, further preventing leakage. And through the deceleration effect, the oil flow speed in the annular oil passage is reduced, offsetting part of the acceleration effect of the centrifugal force on the oil flow, and avoiding the problem of oil film oscillation in the annular oil passage.

[0064] The distance between the inner wall surface and the outer wall surface of the folding part 97 is maintained by an inclined side wall. When the distance shortens, the side wall swings from an inclined state to a horizontal state, and the outer wall moves away from the impeller 11, causing the folding part 97 to unfold. The shape memory metal 98 is pulled, and the shape memory metals 98 switch to a parallel state with each other, and the included angle with the annular oil passage increases. The movable plate 982 is driven and the bending angle between the movable plate 982 and the shape memory metal 98 becomes larger, causing the cutting piece 981 to extend along the bending direction and cut the coke in the oil passage.

[0065] During the ventilation process, the air flow flows along the inner wall of the air inlet 1. Due to the shear force of the inner wall on the air flow, the air flow velocity in this part is relatively slow. It enters the diffuser chamber 2 through the first channel along the inner wall. The air flow accelerates when flowing along the arc surface 95, resulting in a local low-pressure area on the arc surface 95. Combined with the end of the baffle 91 swinging into the second channel, the air flow flowing along the inner wall is guided towards the first channel, so that the air flow provides a pushing force against the connecting member 9 when passing through the connecting member 9. There is a temperature difference on both sides of the baffle 91, so that the air flow flowing through the arc surface 95 will contact the baffle 91 with a higher temperature. The water vapor in the air flow will condense on the side surface of the baffle 91 and will slide down along the baffle 91 to the protrusion 93, where it is condensed by the protrusion 93 to form condensate, and then weathered by the high-speed air flow to form a cycle in the pharynx, reducing the probability of water vapor directly entering the diffuser chamber 2.

[0066] Only some exemplary embodiments of the present invention have been described above by way of illustration. Without doubt, for those of ordinary skill in the art, the described embodiments can be modified in various different ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A centrifugal compressor and diffuser interface structure, comprising a diffuser (21) and an impeller (11) rotatably arranged on its axis, characterized in that: It comprises a connecting member (9) located between a diffuser (21) and an impeller (11), on which a plurality of contact rollers (12) are arranged in a circumferential array; The connecting member (9) comprises: for guiding the airflow toward the outer wall surface of the diffuser (21); An inner wall surface opposite to the impeller (11), wherein the inner wall surface and the outer side of the impeller (11) enclose an annular oil passage for containing lubricating oil; Wherein, the connecting member (9) has a contracted state that shortens the distance between the inner wall surface and the outer wall surface; The outer wall surface of the connecting member (9) and the end surface of the impeller (11) are in a stepped structure, and a shifting plate (91) is provided on the connecting member (9); The outer wall surface of the connecting member (9) is provided with a curved surface (95), and a channel with a decreasing inner diameter is formed between the curved surface (95) and the shifting plate (91).

2. The centrifugal compressor and diffuser interface structure according to claim 1, characterized in that: A predetermined gap is maintained between the side surface of the contact roller (12) and the outer side of the impeller (11), and the contact roller (12) rotates with the impeller (11) to form a vortex of lubricating oil.

3. The centrifugal compressor and diffuser interface structure according to claim 1, characterized in that: It also includes a stabilizing roller (13) which is rotatably arranged on the connecting member (9) and keeps synchronous movement with the contact roller (12).

4. The centrifugal compressor and diffuser interface structure according to claim 1, characterized in that: It also includes a sealing ring (22) fixedly arranged on the impeller (11) and a memory metal (98) in a circumferential array and movably arranged in the interval of the sealing ring (22); the angle between the memory metal (98) and the annular oil passage is adjustable.

5. The centrifugal compressor and diffuser interface structure according to claim 4, characterized in that: A cutting blade (981) pointing in the direction of oil flow is fixedly arranged on the memory metal (98).

6. The centrifugal compressor and diffuser interface structure according to claim 5, characterized in that: The inner wall surface of the connecting piece (9) is provided with a folded portion (97), and the angle of the memory metal (98) is the smallest when the spacing between the folded portions (97) is the smallest.

7. The centrifugal compressor and diffuser interface structure according to claim 1, characterized in that: A heat-sensitive block (92) is arranged at a first end of the dial plate (91) close to the diffuser (21), and a protrusion (93) for guiding condensation is arranged at a second end opposite thereto.

8. The centrifugal compressor and diffuser interface structure according to claim 1, characterized in that: It also comprises a transmission shaft (5) for driving the impeller (11), on which an adjustment unit for controlling the connecting member (9) is arranged, and the adjustment unit comprises an extension rod (53) that moves in the radial direction as the temperature changes.

Images