CN112228225B

CN112228225B - Turbojet engine lubricating system

Info

Publication number: CN112228225B
Application number: CN202011094942.2A
Authority: CN
Inventors: 高华; 黄啸; 陈波
Original assignee: Shanghai Shangshi Energy Technology Co ltd
Current assignee: Shanghai Shangshi Aeroengine Co ltd
Priority date: 2020-10-14
Filing date: 2020-10-14
Publication date: 2021-04-13
Anticipated expiration: 2040-10-14
Also published as: CN112228225A

Abstract

The invention belongs to the technical field of manufacturing of aero-engines, and particularly relates to a turbojet engine lubricating system which comprises a lubricating oil tank, a main shaft, a bearing support, a bearing and a valve component, wherein the bearing support is provided with an oil inlet and an oil outlet; an end cover is arranged at the end part of the bearing support, and an annular air gap is arranged between the inner ring surface of the end cover and the main shaft; the oil inlet hole is communicated with the valve component, the valve component is communicated with the lubricating oil tank, the valve component is communicated with a high-pressure air duct of the turbojet engine, and the oil discharge hole is communicated with the lubricating oil tank; when the turbojet engine is started and the air pressure in the high-pressure air duct is smaller than the designated pressure, the valve assembly can convey lubricating oil to the oil inlet at a constant pressure, and when the turbojet engine is started and the air pressure in the high-pressure air duct is larger than or equal to the designated pressure, the valve assembly can convey lubricating oil to the oil inlet at a floating pressure. The invention realizes the follow-up regulation of the lubricating oil supply pressure by utilizing the valve component, avoids the over-low lubricating oil pressure and ensures the reliable operation of the bearing.

Description

Turbojet engine lubricating system

Technical Field

The invention belongs to the technical field of manufacturing of aero-engines, and particularly relates to a turbojet engine lubricating system.

Background

The aircraft engine mainly comprises a main shaft, a gas compressor, a turbine, a casing, a fuel system, a lubricating oil system and the like, wherein the main shaft is rotatably arranged in a duct of the casing through a bearing, the gas compressor is arranged at the front end of the main shaft, the turbine is arranged at the rear end of the main shaft, a high-pressure air duct is formed between the gas compressor and the turbine, a nozzle and an ignition mechanism of the fuel system are generally positioned in the air duct, and a bearing support mechanism of the main shaft is also generally arranged at the position. The engine need constantly provide lubricating oil in order to guarantee bearing normal operating to the bearing chamber at high-speed operation in-process, and still need set up the device of obturating at the tip of bearing chamber in order to prevent that lubricating oil from revealing, prior art generally adopts the slip sealing washer to obturate, has relative friction between sealing washer and the main shaft, and this one side has increased the rotational resistance of main shaft, and on the other hand main shaft high-speed rotation makes the sealing washer wearing and tearing speed very fast, and life is low. The prior art also provides a wind pressure sealing mechanism, which introduces high-pressure airflow in a high-pressure air duct into a gap between a bearing cavity and a main shaft to form a high-pressure air gap so as to achieve the purpose of sealing; in addition, the air pressure in the bearing cavity fluctuates, and the conventional lubricating oil supply system cannot adjust the oil supply pressure according to the air pressure fluctuation of the bearing cavity, so that the oil supply pressure of the lubricating oil system is possibly insufficient when the pressure of the bearing cavity is increased.

Disclosure of Invention

The invention aims to provide a turbojet engine lubricating system, which can realize the follow-up change of lubricating oil pressure along with the air pressure change of a bearing cavity and avoid the over-low oil supply pressure.

The technical scheme adopted by the invention is as follows:

a turbojet engine lubricating system comprises a lubricating oil tank, a main shaft, a bearing support, a bearing and a valve component, wherein the bearing support is sleeved outside the main shaft and is fixedly connected with a casing of an engine; the bearing is arranged between the main shaft and the bearing support, an annular clamping cavity is arranged between the main shaft and the bearing support, and the bearing support is provided with an oil inlet hole and an oil discharge hole; an end cover is arranged at the end part of the bearing support, an annular air gap is arranged between the inner annular surface of the end cover and the main shaft, one end of the annular air gap is communicated with the annular clamping cavity, and the other end of the annular air gap is communicated with a high-pressure air duct of the turbojet engine; the oil inlet hole is communicated with the valve component, the valve component is communicated with the lubricating oil tank, a lubricating oil pump is arranged between the valve component and the lubricating oil tank, the valve component is communicated with a high-pressure air duct of the turbojet engine, and the oil discharge hole is communicated with the lubricating oil tank; the valve component is assembled to be capable of conveying lubricating oil to the oil inlet hole at constant pressure when the turbojet engine is started and the air pressure in the high-pressure air duct is smaller than the specified pressure, capable of conveying lubricating oil to the oil inlet hole at floating pressure when the turbojet engine is started and the air pressure in the high-pressure air duct is larger than or equal to the specified pressure, capable of synchronously lifting along with the lifting of the air pressure in the high-pressure air duct, and capable of stopping conveying the lubricating oil to the oil inlet hole when the turbojet engine is stopped.

The valve assembly comprises a valve casing, a first valve core and a second valve core, wherein a first valve cavity and a second valve cavity which are perpendicular to each other and communicated are arranged in the valve casing; a second annular groove is formed in the first valve core, the second annular groove is communicated with a second valve cavity, a first air passage is formed in the first valve core, one end of the first air passage is communicated with a first air inlet hole, the other end of the first air passage is communicated with a second annular groove, a first pressure spring is arranged at one end, away from the second annular groove, of the second valve core, a valve pin is arranged at one end, facing the second annular groove, of the second valve core, a pin groove is formed in the second annular groove, and the valve pin and the pin groove are plugged; the third valve core is also arranged in the first valve cavity in a sliding mode, the third valve core is of a hollow tubular structure, one end, far away from the first air inlet hole, of the first valve core is arranged in a center hole of the third valve core in a sliding mode, an oil inlet flow channel and an oil outlet flow channel are arranged on the side wall of the first valve cavity, the oil inlet flow channel is communicated with the lubricating oil pump, the oil outlet flow channel is communicated with the oil inlet hole, a third annular groove is formed in the outer annular surface of the third valve core, the third valve core is connected with the electromagnetic telescopic element, the third valve core is provided with a first station and a second station, the oil inlet flow channel and the oil outlet flow channel are communicated through the third annular groove when the third valve core is located at the first station, and the third annular groove is staggered with the oil inlet flow channel or the oil outlet flow channel to enable the oil inlet flow channel; two radial flow passages penetrating to the central hole of the third valve core are formed in the third ring groove, when the third valve core is positioned at a first station, the two radial flow passages are respectively collinear with the oil inlet flow passage and the oil outlet flow passage, a fourth ring groove is formed in the part, positioned in the third valve core, of the first valve core, a second pressure spring is further arranged in the first valve cavity, the second pressure spring is assembled to enable the first valve core to slide towards the direction close to the first air inlet hole under the action of the elastic force of the second pressure spring, when the valve pin is inserted into the pin groove, the fourth ring groove is staggered with the two radial flow passages, when the air pressure of the first air inlet hole is larger than the specified pressure, the second valve core can be driven to move towards the direction far away from the first valve core, and the valve pin is drawn out from the pin groove, at the moment, the first valve core slides towards the square far away from the first air inlet hole under the action of the air pressure, and the fourth ring groove is communicated with the two radial flow passages, and the first valve core slides in a reciprocating manner along with the change of the air pressure of the first air inlet hole, so that the flow area between the fourth annular groove and the two radial holes is changed.

The bearing support is further provided with an exhaust hole communicated with the annular clamping cavity, the first valve cavity is further provided with a second air inlet hole, a second air outlet hole and an air inlet and outlet hole, a fifth annular groove is formed in the outer annular surface of the third valve core, the exhaust hole is communicated with the air inlet and outlet hole, the second air inlet hole is communicated with an energy accumulator, the second air outlet hole is communicated with air in the lubricating oil tank, the air inlet and outlet hole is communicated with the second air outlet hole through the fifth annular groove when the third valve core is located at a first station, the air inlet and outlet hole is communicated with the second air inlet hole through the fifth annular groove when the third valve core is located at a second station, the energy accumulator is communicated with the high-pressure air duct through a pipeline, a one-way valve is arranged on the pipeline, and the one-way valve is assembled.

And the air in the lubricating oil tank is communicated with the atmosphere.

The oil inlet is evenly arranged along the circumference of the bearing support at intervals, and the inner end of each oil inlet is arranged towards the end face of the bearing.

A movable sealing ring is arranged in the annular air gap and is assembled to close or open the circulator.

The movable sealing ring is configured to open the annular air gap when the third spool is in the first position and to close the annular air gap when the third spool is in the second position.

The main shaft is further provided with a wind shield disc, the wind shield disc and the outer end of the end cover are arranged at intervals, and a gap between the wind shield disc and the end cover is communicated with the annular air gap.

The outer end of the wind shield disc is provided with an induced draft cover fixedly connected with the casing, the induced draft cover comprises an annular end plate parallel to the wind shield disc and an annular side plate parallel to the outer annular surface of the end cover, the annular end plate and the wind shield disc are arranged at intervals, the inner annular surface of the annular end plate and the axial surface of the main shaft are arranged at intervals, the annular side plate and the outer annular surface of the end cover are arranged at intervals, an annular induced draft groove is formed in the position, corresponding to the end portion of the annular side plate, of the outer wall of the bearing support, the notch of the annular induced draft groove is arranged opposite to the direction of the gas compressor, and the annular side plate extends into the induced draft groove and is arranged at a distance from the bottom of the induced draft groove to enable a U.

A high-power gas turbine engine comprises the turbojet engine lubricating system.

The invention has the technical effects that: the invention realizes the follow-up regulation of the lubricating oil supply pressure by utilizing the valve component, improves the oil supply pressure when the air pressure of the bearing cavity is increased, reduces the oil supply pressure when the air pressure of the bearing cavity is reduced, avoids the overlow lubricating oil pressure and ensures the reliable operation of the bearing.

Drawings

FIG. 1 is a cross-sectional view of a sealing mechanism provided by an embodiment of the present invention;

FIG. 2 is a schematic perspective cut-away view of a valve assembly provided in accordance with an embodiment of the present invention, with the valve housing cut in half and the third valve spool cut in one third;

FIG. 3 is a cross-sectional view of a valve assembly provided by an embodiment of the present invention;

FIG. 4 is a schematic diagram of a lubrication system provided by an embodiment of the present invention;

FIG. 5 is a perspective view of a movable seal ring provided by an embodiment of the present invention and an enlarged view of a portion thereof;

FIG. 6 is a half-sectional view of a movable seal ring provided in accordance with an embodiment of the present invention prior to installation;

FIG. 7 is a half-sectional view of a movable seal ring provided in accordance with an embodiment of the present invention after installation;

FIG. 8 is an exploded view and partially enlarged view of a movable seal ring provided by an embodiment of the present invention;

fig. 9 is a perspective view of an annular piston provided by an embodiment of the present invention.

Detailed Description

In order that the objects and advantages of the invention will be more clearly understood, the following description is given in conjunction with the accompanying examples. It is to be understood that the following text is merely illustrative of one or more specific embodiments of the invention and does not strictly limit the scope of the invention as specifically claimed.

As shown in fig. 1 and 4, a high-power gas turbine engine comprises a casing, a bearing support 20 is fixedly arranged in the casing, a main shaft 10 is rotatably connected with the bearing support 20 through a bearing 60, a compressor impeller is connected to the front end of the main shaft 10, a turbine is connected to the rear end of the main shaft 10, and the bearing support 20 is located in a high-pressure air duct 1 between the compressor and the turbine; an annular clamping cavity 21 is formed between the main shaft 10 and the bearing support 20, and an oil inlet hole 22 and an oil discharge hole 23 are formed in the bearing support 20; the end part of the bearing support 20 is provided with an end cover 30, a sealing mechanism is arranged between the inner annular surface of the end cover 30 and the main shaft 10, the sealing mechanism comprises an annular air gap 34 formed between the inner annular surface of the end cover 30 and the outer annular surface of the main shaft 10 at intervals, and a movable sealing ring 33 arranged on the through-flow section of the annular air gap 34, one end of the annular air gap 34 is communicated with the annular clamping cavity 21, the other end of the annular air gap is communicated with the high-pressure air duct 1 outside the bearing support 20, the movable sealing ring 33 is assembled in a way that the annular air gap 34 can be sealed by the movable sealing ring 33 when the air pressure in the high-pressure air duct 1 is smaller than a specified pressure, and the annular air gap 34 can be opened by the movable sealing ring.

According to the invention, the movable sealing ring 33 is arranged in the annular air gap 34, when the air pressure in the high-pressure air duct 1 is lower than the preset pressure, the movable sealing ring 33 can seal the annular air gap 34, so that the lubricating oil is prevented from seeping out of the annular air gap 34 under the condition of low rotating speed, and when the air pressure in the high-pressure air duct 1 is greater than or equal to the preset pressure, the movable sealing ring 33 can open the annular air gap 34, and at the moment, the movable sealing ring 33 is separated from the main shaft 10, so that the abrasion speed of the sealing ring under the condition of high rotating speed is effectively reduced, the service.

Further, as shown in fig. 4, the oil inlet 22 is communicated with the valve assembly 70, the valve assembly 70 is communicated with the lubricating oil tank 80, a lubricating oil pump 81 is arranged between the valve assembly 70 and the lubricating oil tank 80, the valve assembly 70 is communicated with the high-pressure air duct 1 of the turbojet engine, and the oil outlet 23 is communicated with the lubricating oil tank 80; the valve assembly 70 is assembled such that the valve assembly 70 can deliver the lubricating oil to the oil inlet 22 at a constant pressure when the turbojet engine is started and the air pressure in the high-pressure air duct 1 is less than a designated pressure, the valve assembly 70 can deliver the lubricating oil to the oil inlet 22 at a floating pressure when the turbojet engine is started and the air pressure in the high-pressure air duct 1 is greater than or equal to the designated pressure, the oil pressure is synchronously raised and lowered with the rise and fall of the air pressure in the high-pressure air duct 1, and the valve assembly 70 can stop delivering the lubricating oil to the oil inlet 22 when the turbojet engine is stopped. The invention utilizes the valve component 70 to realize the follow-up regulation of the lubricating oil supply pressure, the lubricating oil supply pressure is improved when the air pressure of the bearing cavity is increased, the lubricating oil supply pressure is reduced when the air pressure of the bearing cavity is reduced, the lubricating oil pressure is prevented from being too low, and the reliable operation of the bearing 60 is ensured.

Preferably, as shown in fig. 1, an annular piston 31 is provided at the inner end of the end cap 30, the annular piston 31 and a piston cavity 32 provided at the inner end of the end cap 30 form a sliding fit, a step portion 311 protruding radially inward is provided on the annular piston 31, an inner annular surface of the step portion 311 is flush with an inner annular surface of the end cap 30, the movable sealing ring 33 includes a rubber ring 331 having a U-shaped cross section, two ends of the rubber ring 331 are respectively fixedly connected with the end cap 30 and the step portion 311, when the step portion 311 approaches the end surface of the end cap 30, the rubber ring 331 can be pressed to arch the rubber ring 331 into the annular air gap 34 to close the annular air gap 34, and when the step portion 311 leaves the end surface of the end cap 30, the rubber ring 331 can be stretched to move out from the annular air gap 34 to open the; the valve assembly 70 is assembled to disconnect the piston cavity 32 from the high-pressure air duct 1 when the air pressure in the high-pressure air duct 1 is less than a specified pressure, and connect the piston cavity 32 with the high-pressure air duct 1 when the air pressure in the high-pressure flow passage is greater than or equal to the specified pressure; when the piston chamber 32 is inflated, the annular piston 31 can be driven to slide and move the step part 311 away from the end cover 30. According to the invention, the expansion and contraction of the movable sealing ring 33 are controlled by the annular piston 31, and then the annular piston 31 is driven to act by high-pressure airflow in the high-pressure air duct 1, so that the follow-up change of the air pressure of the movable sealing ring 33 and the high-pressure air duct 1 is skillfully realized.

Specifically, as shown in fig. 2 and 3, the valve assembly 70 includes a valve housing 74, a first valve spool 71 and a second valve spool 72, a first valve cavity and a second valve cavity which are perpendicular to each other and communicated with each other are arranged in the valve shell 74, the first valve core 71 is arranged in the first valve cavity in a sliding mode, the second valve core 72 is arranged in the second valve cavity in a sliding mode, a first annular groove 743 is arranged in the first valve cavity, a first air outlet hole 742 penetrating to the outer wall of the valve casing 74 is arranged on the first annular groove 743, the first air outlet hole 742 is communicated with the piston cavity 32, a first air inlet hole 741 is arranged at one end of the first valve cavity, the first air inlet hole 741 is communicated with the high-pressure air duct 1, when one end of the first spool 71 facing the first suction hole 741 is positioned in the first annular groove 743, the first suction hole 741 can communicate with the first discharge hole 742, when one end of the first spool 71 facing the first suction hole 741 is positioned between the first annular groove 743 and the first suction hole 741, the first suction hole 741 can be disconnected from the first discharge hole 742; the first valve core 71 is provided with a second annular groove 712, the second annular groove 712 is communicated with a second valve cavity, a first air channel 711 is arranged in the first valve core 71, one end of the first air channel 711 is communicated with a first air inlet hole 741, the other end of the first air channel 711 is communicated with the second annular groove 712, one end of the second valve core 72, which is far away from the second annular groove 712, is provided with a first pressure spring 75, one end of the second valve core 72, which faces the second annular groove 712, is provided with a valve pin 721, a pin groove 713 is arranged in the second annular groove 712, the valve pin 721 is inserted into the pin groove 713, when the air pressure of the first air inlet hole 741 is higher than a specified pressure, the second valve core 72 can be driven to move in a direction far away from the first valve core 71 and be drawn out from the pin groove 713, and the first air inlet hole 741 and the first air outlet hole 742 are communicated with each other by sliding the first valve core; a second pressure spring 76 is also arranged in the first valve cavity, and the second pressure spring 76 is assembled to enable the elastic force of the second pressure spring to drive the first valve core 71 to slide towards the direction close to the first air inlet hole 741; the third valve core 73 is also arranged in the first valve cavity in a sliding mode, the third valve core 73 is of a hollow tubular structure, one end, far away from the first air inlet hole 741, of the first valve core 71 is arranged in a center hole of the third valve core 73 in a sliding mode, an oil inlet flow passage 744 and an oil outlet flow passage 745 are arranged on the side wall of the first valve cavity, the oil inlet flow passage 744 is communicated with the lubricating oil pump 81, the oil outlet flow passage 745 is communicated with the oil inlet hole 22, a third annular groove 731 is arranged on the outer annular surface of the third valve core 73, the third valve core 73 is connected with an electromagnetic telescopic element, the third valve core 73 is provided with a first station and a second station, the oil inlet flow passage 744 and the oil outlet flow passage 745 are communicated through the third annular groove 731 when the third valve core 73 is located at the first station, and the third annular groove 731 and the oil inlet flow passage 744 or the oil outlet flow passage 745 are staggered to disconnect the oil inlet flow passage 744 and the; two radial flow passages 732 penetrating through the central hole of the third valve spool 73 are formed in the third annular groove 731, when the third valve spool 73 is in the first position, the two radial flow passages 732 are respectively collinear with the oil inlet flow passage 744 and the oil outlet flow passage 745, a fourth annular groove 714 is formed in the portion, located in the third valve spool 73, of the first valve spool 71, a second pressure spring 76 is further arranged in the first valve cavity, the second pressure spring 76 is assembled to enable the first valve spool 71 to slide in the direction close to the first air inlet hole 741 due to the elastic force of the second pressure spring 76, when the valve pin 721 is inserted into the pin groove 713, the fourth annular groove 714 is staggered with the two radial flow passages 732, when the air pressure of the first air inlet hole 741 is higher than a specified pressure, the second valve spool 72 can be driven to move in the direction away from the first valve spool 71 and the valve pin 721 is drawn out of the pin groove 713, at this time, the first valve spool 71 slides in the square away from the first air inlet hole 741 due to enable, and the first valve spool 71 slides back and forth with the change of the air pressure of the first air inlet hole 741 so that the flow area between the fourth groove 714 and the two radial holes is changed. According to the invention, the delayed start of the first valve core 71 is realized by using the second valve core 72, the first valve core 71 can be instantly opened only when the air pressure reaches the specified pressure, and the first valve core 71 is prevented from floating when the air pressure does not reach the specified air pressure, so that the situation of poor sealing in a closed state of the movable sealing ring 33 is avoided.

Preferably, as shown in fig. 5, 6, 7, and 8, two ends of the rubber ring 331 are respectively provided with a quick-connect ring, the two quick-connect rings are respectively connected with the end cover 30 and the step portion 311 in a snap-fit manner, and the two quick-connect rings are identical in structure and are symmetrically arranged; the quick-connecting ring comprises a ring seat 332, wherein a plurality of first elastic clamping protrusions 333 are arranged on the outer ring surface of the ring seat 332 at intervals along the circumferential direction, a first axial sliding groove 3321 is formed in the inner side of each first elastic clamping protrusion 333, when the first elastic clamping protrusions 333 are pressed, the first elastic clamping protrusions can elastically contract towards the inner side of the first axial sliding groove 3321, a locking plate 334 is arranged in each first axial sliding groove 3321, the locking plate 334 is in sliding fit with the first axial sliding groove 3321, and when the locking plate 334 slides to the inner side of each first elastic clamping protrusion 333, the first elastic clamping protrusions 333 can be prevented from contracting towards the inner side of the axial sliding groove; a second axial sliding groove 3322 with the width smaller than that of the first axial sliding groove 3321 is arranged on the inner side of the first axial sliding groove 3321; a second elastic clamping protrusion 335 is arranged in the second axial sliding groove 3322, the second elastic clamping protrusion 335 protrudes into the first axial sliding groove 3321 to prevent the locking plate 334 from sliding towards the inner region of the first elastic clamping protrusion 333, a movable pressing plate 336 which is arranged in an axial sliding manner is also arranged in the second axial sliding groove 3322, and when the movable pressing plate 336 covers the second elastic clamping protrusion 335, the second elastic clamping protrusion 335 can be moved out of the first axial sliding groove 3321; the movable pressing plate 336 and the locking plate 334 respectively protrude out of two ends of the ring seat 332, the locking plates 334 of the two quick-connecting rings protrude in opposite directions, and the movable pressing plates 336 of the two quick-connecting rings protrude in opposite directions; the end surfaces of the end cover 30 and the step portion 311 which are opposite to each other are respectively provided with a step groove, the side wall of each step groove is provided with an annular clamping groove, and when the quick-connection ring is arranged in the step groove, the first clamping protrusion is clamped in the annular clamping groove. The invention provides an integrated movable sealing structure which can effectively reduce the installation difficulty of a movable sealing ring 33, and the specific installation method comprises the following steps: the movable sealing ring 33 is initially placed between the end cap 30 and the annular piston 31, the end cap 30 and the annular piston 31 are used to press the quick-connect rings at two sides, respectively, the locking plates 334 on the two quick-connect rings are in mutual interference during the pressing process, but are not immediately inserted below the first elastic clamping protrusion 333 due to the blocking of the second elastic clamping protrusion 335, at the moment, the first elastic clamping protrusion 333 is pressed by the side wall of the stepped groove to contract inwards, when the quick-connect rings are close to the end surface of the stepped groove, the end surface of the stepped groove presses the movable pressing plate 336, so that the second elastic clamping protrusion 335 is staggered with respect to the locking plate 334, when the quick-connect rings are in contact with the end surface of the stepped groove, the first elastic clamping protrusion 333 rebounds into the annular clamping groove, and the locking plate 334 slides below the first elastic clamping protrusion 333 due to the blocking of the second elastic clamping protrusion 335 being lost, thereby sealing the deformation path of the first elastic clamping protrusion 333, thereby effectively connecting the quick-connecting ring with the step groove.

Furthermore, an elastic element for driving the two quick-connection rings to approach each other is arranged between the two quick-connection rings; the elastic element comprises a plurality of V-shaped reeds 337 arranged at intervals along the circumferential direction of the quick-connection ring, and two ends of each V-shaped reed 337 are fixedly connected with the two quick-connection rings respectively. The elastic element is used to effect the return of the annular piston 31.

Further, as shown in fig. 1, a wind shielding disc 40 is further disposed on the main shaft 10, the wind shielding disc 40 is disposed at an interval from an outer end of the end cover 30, a gap between the wind shielding disc 40 and the end cover 30 is communicated with the annular air gap 34, an induced draft cover 50 fixedly connected with the casing is arranged at the outer end of the wind shield disc 40, the induced draft cover 50 comprises an annular end plate parallel to the wind shield disc 40 and an annular side plate parallel to the outer annular surface of the end cover 30, the annular end plate and the wind shield disc 40 are arranged at intervals, the inner annular surface of the annular end plate and the axial surface of the main shaft 10 are arranged at intervals, the annular side plate and the outer annular surface of the end cover 30 are arranged at intervals, an annular air guide groove 26 is arranged at the position of the outer wall of the bearing bracket 20 corresponding to the end part of the annular side plate, the notch of the annular air guide groove 26 is opposite to the direction of the compressor, and the annular side plate protrudes into the air guide groove 26 and is arranged at a certain distance from the bottom of the air guide groove 26, so that a U-shaped air channel is formed between the air guide groove 26 and the annular side plate.

Further, as shown in fig. 1 and 9, an annular wind-blocking ring 312 is disposed between the end cover 30 and the wind-blocking disc 40, the annular wind-blocking ring 312 is slidably connected to the end cover 30, the annular wind-blocking ring 312 is fixedly connected to the annular piston 31, an annular shallow groove opposite to the annular wind-blocking ring 312 is disposed on the wind-blocking disc 40, when the step portion 311 is close to the end cover 30, the annular wind-blocking ring 312 is inserted into the annular shallow groove, and the annular shallow groove are in clearance fit to reduce a through-flow cross section of a gap between the wind-blocking disc 40 and the end cover 30, and when the step portion 311 is far away from the end cover 30, the annular wind-blocking ring 312 contracts and the end cover 30 to; the end cover 30 comprises an inner ring and an outer ring, the annular wind blocking ring 312 penetrates through an annular gap between the inner ring and the outer ring, a kidney-shaped hole 313 is formed in the annular wind blocking ring 312, the inner ring and the outer ring are fixedly connected through a pin 35 which is radially arranged, and the pin 35 penetrates through the kidney-shaped hole 313. The annular wind deflector 312, when closed, prevents the high pressure gas flow from forcing the movable sealing ring 33 open in the closed position.

Further, as shown in fig. 1, 2, 3 and 4, the bearing support 20 is further provided with an exhaust hole 25 communicated with the annular clamping cavity 21, the first valve cavity is also provided with a second air inlet hole 748, a second air outlet hole 747 and an air inlet and outlet hole 746, a fifth annular groove 733 is formed on the outer annular surface of the third valve core 73, the exhaust hole 25 is communicated with the air inlet/outlet hole 746, the second air inlet hole 748 is communicated with the accumulator 90, the second air outlet hole 747 is communicated with the air in the lubricating oil tank 80, when the third valve core 73 is at the first position, the air inlet/outlet hole 746 is communicated with the second air outlet hole 747 through the fifth ring groove 733, when the third valve core 73 is at the second position, the air inlet/outlet hole 746 is communicated with the second air inlet hole 748 through the fifth ring groove 733, the energy accumulator 90 is communicated with the high-pressure air duct 1 through a pipeline, a one-way valve 91 is arranged on the pipeline, and the one-way valve 91 is assembled to enable air flow to flow from the high-pressure air duct 1 to the energy accumulator 90. The exhaust hole 25 can release pressure to the bearing cavity in an oil supply state, reliable pressure difference between the bearing cavity and the high-pressure air duct 1 is ensured, the energy accumulator 90 can collect a certain amount of high-pressure air in the running process of the engine, the energy accumulator 90 is communicated with the exhaust hole 25 when the engine is stopped, and the bearing cavity is in a closed environment at the moment, so that the high-pressure air in the energy accumulator 90 enters the bearing cavity and can quickly discharge lubricating oil in the bearing cavity.

Preferably, the air in the oil tank 80 is connected to the atmosphere. The oil inlet holes 22 are uniformly arranged along the circumferential direction of the bearing bracket 20 at intervals, and the inner end of each oil inlet hole 22 faces the end face of the bearing 60.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that those skilled in the art can make various improvements and modifications without departing from the principle of the present invention, and these improvements and modifications should also be construed as the protection scope of the present invention. Structures, devices, and methods of operation not specifically described or illustrated herein are generally practiced in the art without specific recitation or limitation.

Claims

1. A turbojet engine lubrication system characterized in that: the lubricating oil pump comprises a lubricating oil tank (80), a main shaft (10), a bearing support (20), a bearing (60) and a valve component (70), wherein the bearing support (20) is sleeved outside the main shaft (10), and the bearing support (20) is fixedly connected with a casing of an engine; the bearing (60) is arranged between the main shaft (10) and the bearing support (20), an annular clamping cavity (21) is arranged between the main shaft (10) and the bearing support (20), and the bearing support (20) is provided with an oil inlet hole (22) and an oil discharge hole (23); an end cover (30) is arranged at the end part of the bearing support (20), an annular air gap (34) is arranged between the inner annular surface of the end cover (30) and the main shaft (10), one end of the annular air gap (34) is communicated with the annular clamping cavity (21), and the other end of the annular air gap is communicated with a high-pressure air duct (1) of the turbojet engine; the oil inlet hole (22) is communicated with the valve assembly (70), the valve assembly (70) is communicated with the lubricating oil tank (80), a lubricating oil pump (81) is arranged between the valve assembly (70) and the lubricating oil tank (80), the valve assembly (70) is communicated with a high-pressure air duct (1) of the turbojet engine, and the oil discharge hole (23) is communicated with the lubricating oil tank (80); the valve assembly (70) is assembled to convey lubricating oil to the oil inlet (22) at a constant pressure when the turbojet engine is started and the air pressure in the high-pressure air duct (1) is less than a specified pressure, the valve assembly (70) can convey lubricating oil to the oil inlet (22) at a floating pressure when the turbojet engine is started and the air pressure in the high-pressure air duct (1) is greater than or equal to the specified pressure, the oil pressure synchronously rises and falls along with the rise and fall of the air pressure in the high-pressure air duct (1), and the valve assembly (70) can stop conveying the lubricating oil to the oil inlet (22) when the turbojet engine is stopped; the valve assembly (70) comprises a valve casing (74), a first valve core (71) and a second valve core (72), a first valve cavity and a second valve cavity which are perpendicular to each other and communicated are arranged in the valve casing (74), the first valve core (71) is arranged in the first valve cavity in a sliding mode, the second valve core (72) is arranged in the second valve cavity in a sliding mode, one end of the first valve cavity is a first air inlet hole (741), and the first air inlet hole (741) is communicated with the high-pressure air duct (1); a second annular groove (712) is formed in the first valve core (71), the second annular groove (712) is communicated with the second valve cavity, a first air channel (711) is arranged in the first valve core (71), one end of the first air channel (711) is communicated with a first air inlet hole (741), the other end of the first air channel is communicated with the second annular groove (712), a first pressure spring (75) is arranged at one end, away from the second annular groove (712), of the second valve core (72), a valve pin (721) is arranged at one end, facing the second annular groove (712), of the second valve core (72), a pin groove (713) is formed in the second annular groove (712), and the valve pin (721) is inserted into the pin groove (713); the oil inlet valve further comprises a third valve core (73), the third valve core (73) is also arranged in the first valve cavity in a sliding mode, the third valve core (73) is of a hollow tubular structure, one end, far away from the first air inlet hole (741), of the first valve core (71) is arranged in a center hole of the third valve core (73) in a sliding mode, an oil inlet flow passage (744) and an oil outlet flow passage (745) are arranged on the side wall of the first valve cavity, the oil inlet flow passage (744) is communicated with the lubricating oil pump (81), the oil outlet flow passage (745) is communicated with the oil inlet hole (22), a third annular groove (731) is formed in the outer annular surface of the third valve core (73), the third valve core (73) is connected with the electromagnetic telescopic element, the third valve core (73) is provided with a first station and a second station, the oil inlet flow passage (744) and the oil outlet flow passage (745) are communicated through the third annular groove (731) when the third valve core (73) is located at the first station, and the third annular groove (731) is staggered with the oil inlet flow passage (744) or The flow passage (744) is disconnected from the oil outlet flow passage (745); two radial flow passages (732) penetrating to a central hole of the third valve core (73) are formed in the third annular groove (731), when the third valve core (73) is positioned at a first station, the two radial flow passages (732) are respectively collinear with the oil inlet flow passage (744) and the oil outlet flow passage (745), a fourth annular groove (714) is formed in the part, positioned in the third valve core (73), of the first valve core (71), a second pressure spring (76) is further arranged in the first valve cavity, the second pressure spring (76) is assembled to enable the first valve core (71) to slide towards the direction close to the first air inlet hole (741) under the action of the elastic force of the second pressure spring, when the valve pin (721) is inserted into the pin groove (713), the fourth annular groove (714) is staggered with the two radial flow passages (732), and when the air pressure of the first air inlet hole (741) is greater than a designated pressure, the second valve core (72) can be driven to move towards the direction far away from the first valve core (71) and the valve pin (721) can be, at the moment, the first valve core (71) slides towards the square far away from the first air inlet hole (741) under the action of air pressure, the fourth annular groove (714) is communicated with the two radial flow channels (732), and the first valve core (71) slides in a reciprocating mode along with the change of the air pressure of the first air inlet hole (741) so that the flow area between the fourth annular groove (714) and the two radial flow holes is changed.

2. The turbojet engine lubrication system of claim 1, wherein: the bearing support (20) is further provided with an exhaust hole (25) communicated with the annular clamping cavity (21), the first valve cavity is further provided with a second air inlet hole (748), a second air outlet hole (747) and an air inlet and outlet hole (746), a fifth ring groove (733) is arranged on the outer ring surface of the third valve core (73), the exhaust hole (25) is communicated with the air inlet and outlet hole (746), the second air inlet hole (748) is communicated with the energy accumulator (90), the second air outlet hole (747) is communicated with air in the lubricating oil tank (80), the air inlet and outlet hole (746) is communicated with the second air outlet hole (747) through the fifth ring groove (733) when the third valve core (73) is positioned at a first station, the air inlet and outlet hole (746) is communicated with the second air inlet hole (733) through the fifth ring groove (733) when the third valve core (73) is positioned at a second station, the energy accumulator (90) is communicated with the high-pressure air duct (1) through a pipeline, and a one-way valve (, the check valve (91) is configured to allow only air flow from the high pressure stack (1) to the accumulator (90).

3. The turbojet engine lubrication system of claim 2, wherein: the air in the lubricating oil tank (80) is communicated with the atmosphere.

4. The turbojet engine lubrication system of claim 3, wherein: the oil inlet holes (22) are uniformly arranged along the circumferential direction of the bearing support (20) at intervals, and the inner end of each oil inlet hole (22) faces the end face of the bearing (60).

5. The turbojet engine lubrication system of claim 2, wherein: a movable sealing ring (33) is arranged in the annular air gap (34), and the movable sealing ring (33) is assembled to close or open the circulator.

6. The turbojet engine lubrication system of claim 5, wherein: the movable sealing ring (33) is assembled to open the annular air gap (34) by the movable sealing ring (33) when the third valve core (73) is in the first position, and to close the annular air gap (34) by the movable sealing ring (33) when the third valve core (73) is in the second position.

7. The turbojet engine lubrication system of claim 2, wherein: the main shaft (10) is further provided with a wind shield disc (40), the wind shield disc (40) and the outer end of the end cover (30) are arranged at intervals, and a gap between the wind shield disc (40) and the end cover (30) is communicated with the annular air gap (34).

8. The turbojet engine lubrication system of claim 7, wherein: the outer end of the wind shield disc (40) is provided with a wind guide cover (50) fixedly connected with the casing, the wind guide cover (50) comprises an annular end plate parallel to the wind shield disc (40) and an annular side plate parallel to the outer annular surface of the end cover (30), the annular end plate and the wind shield disc (40) are arranged at intervals, the inner annular surface of the annular end plate and the axial surface of the main shaft (10) are arranged at intervals, the annular side plate and the outer annular surface of the end cover (30) are arranged at intervals, an annular wind guide groove (26) is arranged at the position, corresponding to the end part of the annular side plate, of the outer wall of the bearing support (20), the notch of the annular wind guide groove (26) is arranged opposite to the direction of the air compressor, and the annular side plate protrudes into the wind guide groove (26) and is arranged at a distance from the bottom of the wind guide groove (26) to enable a U-shaped.

9. A high power gas turbine engine, characterized by: including the turbojet engine lubrication system of any one of claims 1 to 8.