Centrifugal self-actuated flow aviation friction clutch

Abstract

This invention belongs to the field of mechanical transmission technology, specifically relating to a centrifugal self-driven flow-controlled aviation friction clutch, including an input shaft, a friction assembly, a piston cylinder, and a lubrication mechanism. The lubrication mechanism includes an oil supply shaft and a flow channel control assembly. The oil supply shaft has a lubrication oil passage extending to the inner ring of the friction assembly. The flow channel control assembly includes a control sleeve fitted onto the oil supply shaft and a linear drive component driven by the control sleeve. The linear drive component is controlled by the piston cylinder. The control sleeve has a through hole, and the linear drive component drives the control sleeve to misalign or align the through hole with the port of the lubrication oil passage. By linking the piston cylinder and the flow channel control assembly, and utilizing existing drive components, the automatic switching of the oil supply logic is achieved without the need for an additional control system. While ensuring heat dissipation performance during engagement, it fundamentally alleviates the energy loss, dynamic interference, and heat accumulation problems caused by continuous oil supply in the disengaged state of traditional wet clutches.

Description

Technical Field

[0001] This invention belongs to the field of mechanical transmission technology, specifically relating to a centrifugal self-driven flow-controlled aviation friction clutch. Background Technology

[0002] Friction clutches are key components in aerospace power transmission systems, high-performance vehicle transmission systems, and heavy industrial machinery, and their performance directly affects the reliability and efficiency of the entire propulsion system. Friction clutches use lubricating oil to cool and lubricate the friction pair, thus suppressing problems such as material thermal exhaustion, surface ablation, and degradation of frictional properties caused by frictional heat generation during engagement.

[0003] However, existing friction clutches generally employ a fixed oil supply structure or a continuous oil supply strategy, meaning that regardless of whether the clutch is engaged or disengaged, lubricating oil is continuously supplied to the friction pair area through a fixed oil passage within the housing or input shaft. While this design effectively controls temperature rise during engagement, it introduces a series of technical problems during disengagement: First, the lubricating oil remaining between the friction plates and the mating steel plates forms a stable oil film structure under the action of centrifugal force at high speed, generating a significant hydrodynamic pressure effect and viscous shear resistance, thus forming a drag torque (also known as belt torque) that cannot be ignored. This drag torque not only causes unnecessary energy loss and reduces the overall efficiency of the system, but may also interfere with the dynamic stability of the transmission system, especially under conditions of multiple clutches in parallel or high-speed switching.

[0004] Secondly, due to the lack of an oil drainage mechanism, the lubricating oil in the friction interface is difficult to drain quickly, which hinders the separation process of the friction pair, prolongs the clutch response time, and reduces control precision and dynamic performance. This problem is particularly critical in applications with frequent start-stop or rapid gear shifting.

[0005] Furthermore, under high-speed conditions, the aforementioned oil film effect is further amplified: the increased centrifugal force makes it more difficult for the oil film to detach from the friction interface, the dragging torque increases nonlinearly, and at the same time, heat accumulation may form in local areas due to oil retention, which weakens the cooling efficiency of the lubrication system and forms a vicious cycle between "lubrication - heat generation - dragging". Summary of the Invention

[0006] The technical problem to be solved by this application is to provide a centrifugal self-driven flow-controlled aviation friction clutch that can dynamically adjust the lubricating oil supply path according to the clutch working state, so as to ensure sufficient lubrication and cooling during the engagement stage, effectively suppress the drag torque during the disengagement stage, and improve system efficiency, response speed and operational stability.

[0007] This application provides a centrifugal self-driven flow-controlled aircraft friction clutch, including an input shaft, a housing connected to the input shaft, a friction assembly disposed within the housing, a piston cylinder for pressing or releasing the friction assembly, an output shaft cooperating with the friction assembly, and a lubrication mechanism; the lubrication mechanism includes: An oil supply shaft is connected to the input shaft and has a lubrication oil passage, which is connected to the input shaft and extends to the inner ring of the friction assembly; The flow channel control assembly includes a control sleeve movably sleeved on the oil supply shaft and a linear drive member drivenly connected to the control sleeve; the linear drive member is controlled by the piston cylinder, the control sleeve is provided with a through hole, and the linear drive member drives the control sleeve to misalign or align the through hole with the port of the lubricating oil passage, so as to block or open the lubricating oil passage.

[0008] Optionally, the piston cylinder includes a cylinder body disposed at one end of the friction assembly, a first piston disposed in the cylinder body and attached to the friction assembly, and a first elastic reset structure for resetting the first piston. The linear drive includes a second piston disposed in the cylinder and arranged opposite to the first piston, and a second elastic reset structure for resetting the second piston; the second piston is connected to the control sleeve via a piston rod.

[0009] Optionally, the force required to push the second piston is less than the force required to push the first piston, and the response speed of the control sleeve is faster than the response speed of the friction assembly.

[0010] Optionally, the oil supply shaft has a central hole, a plurality of circumferentially distributed oil inlets communicating with the oil inlet of the input shaft, and a plurality of circumferentially distributed first oil-throwing holes radially toward the inner ring of the friction assembly. The lubrication circuit includes a central hole, oil inlets, and first oil-throwing holes, and the first oil-throwing holes correspond to the through holes on the control sleeve.

[0011] Optionally, an annular groove is provided between the oil inlet of the input shaft and the oil inlet hole.

[0012] Optionally, the number of oil inlet holes is 4 to 8, and the diameter is 4 mm to 8 mm; the first oil slinger holes are distributed in 3 rows along the axial direction of the oil supply shaft, with 4 to 8 holes in each row and a diameter of 1.2 mm to 1.8 mm.

[0013] Optionally, a sealing cap is provided at the end of the oil supply shaft away from the first oil slinger hole, and an elastic retaining ring is embedded in the input shaft abutting against the end of the oil supply shaft. The oil supply shaft and the input shaft are axially stepped together, and sealing rings are provided between the two sides of the oil supply shaft near the annular groove and the input shaft.

[0014] Optionally, one end of the oil supply shaft is provided with a plurality of second oil-throwing holes inclined toward the inner wall of the output shaft, and the inner wall of the output shaft is provided with a plurality of third oil-throwing holes distributed circumferentially.

[0015] Optionally, the output shaft has a plurality of circumferentially distributed grooves on the surface of the inner ring of the friction assembly. Each groove has a plurality of oil guide holes that penetrate the output shaft and are distributed along the axial direction. The inner wall of the output shaft has a spacer between the oil guide holes and the third oil slinger hole to prevent the lubricating oil from flowing back. The inner wall of the output shaft and the outer wall of the oil supply shaft have an annular gap to form an oil inlet cavity.

[0016] Optionally, the friction assembly includes a steel sheet, a friction plate, and a diaphragm spring, wherein the steel sheet and the friction plate are stacked, and the diaphragm spring is disposed between two adjacent steel sheets.

[0017] Optionally, the diaphragm spring has an overall ring structure and a wave-shaped elastic structure along its circumference.

[0018] The beneficial effects of this application are that, by setting a flow channel control component linked to the piston cylinder, the lubrication mechanism can dynamically adjust the flow of lubricating oil according to the working state of the clutch (engaged or disengaged): when the clutch is engaged, the through hole of the control sleeve is aligned with the lubricating oil passage to ensure that the friction pair receives sufficient lubrication and cooling; when the clutch is disengaged, the through hole is misaligned with the oil passage to cut off the lubricating oil supply, effectively reducing the formation of residual oil film between the friction plates and the mating steel plates, thereby significantly reducing drag torque, improving system efficiency, accelerating the lubricating oil discharge speed, shortening response time, and improving control accuracy. Thus, by utilizing the existing drive component—the piston cylinder—automatic switching of the oil supply logic is achieved without the need for an additional control system. While ensuring heat dissipation performance during engagement, it fundamentally alleviates the energy loss, dynamic interference, and heat accumulation problems caused by continuous oil supply in the disengaged state of traditional wet clutches, thereby improving the overall operational stability and adaptability of the clutch over a wide range of operating conditions. Attached Figure Description

[0019] Figure 1 A three-dimensional structural schematic diagram of a centrifugal self-driven flow-controlled aviation friction clutch provided in an embodiment of this application; Figure 2 A schematic axial cross-sectional view of a centrifugal self-driven flow-controlled aviation friction clutch provided in an embodiment of this application; Figure 3 A schematic diagram of the engagement state of the friction assembly of a centrifugal self-driven flow-controlled aviation friction clutch provided in an embodiment of this application; Figure 4 A schematic diagram of the disengaged state of the friction assembly of a centrifugal self-driven flow-controlled aviation friction clutch provided in an embodiment of this application; Figure 5 This is a schematic diagram of the structure of the oil supply shaft provided in an embodiment of this application; Figure 6 This is a schematic diagram of the output shaft provided in an embodiment of this application; Figure 7 (a) is a three-dimensional structural schematic diagram of a plurality of diaphragm springs provided in an embodiment of this application; Figure 7 (b) is a schematic diagram of the axial surface of the diaphragm spring provided in the embodiments of this application; Figure 7 (c) is a side view of a plurality of diaphragm springs provided in an embodiment of this application.

[0020] In the diagram: 100, input shaft; 110, oil inlet; 120, elastic retaining ring; 130, sealing ring; 200, housing; 210, oil outlet; 300, friction assembly; 310, steel plate; 320, friction plate; 330, diaphragm spring; 340, end retaining ring; 400, piston cylinder; 410, cylinder body; 411, hydraulic oil inlet; 420, first piston; 430, first elastic reset structure; 500, output shaft; 5 10. Third oil slinger hole; 520. Groove; 530. Oil guide hole; 540. Oil inlet cavity; 550. Spacer ring; 610. Oil supply shaft; 611. Center hole; 612. Oil inlet hole; 613. First oil slinger hole; 614. Second oil slinger hole; 615. Annular groove; 616. Sealing cap; 620. Flow channel control assembly; 621. Control sleeve; 6211. Through hole; 622. Second piston; 623. Second elastic reset structure. Detailed Implementation

[0021] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0022] To better understand this application, the background technology of this application will be introduced first.

[0023] Centrifugal self-driven flow-controlled aerospace friction clutches are key components in aerospace power transmission systems, high-performance vehicle transmission systems, and heavy industrial machinery, and their performance directly affects the reliability and efficiency of the entire propulsion system. Centrifugal self-driven flow-controlled aerospace friction clutches use lubricating oil to cool and lubricate the friction pairs, thus suppressing problems such as material thermal exhaustion, surface ablation, and degradation of frictional performance caused by frictional heat generation during engagement.

[0024] However, traditional centrifugal self-driven flow-controlled aviation friction clutches generally employ a fixed oil supply structure or a continuous oil supply strategy. This means that regardless of whether the clutch is engaged or disengaged, lubricating oil is continuously supplied to the friction pair area through a fixed oil passage within the housing or input shaft. While this design effectively controls temperature rise during engagement, it introduces a series of technical problems during disengagement: First, the lubricating oil remaining between the friction plates and the mating steel plates forms a stable oil film structure under the action of centrifugal force at high speed, generating a significant hydrodynamic pressure effect and viscous shear resistance, thus forming a drag torque (also known as belt torque) that cannot be ignored. This drag torque not only causes unnecessary energy loss and reduces the overall efficiency of the system, but may also interfere with the dynamic stability of the transmission system, especially under conditions of multiple clutches in parallel or high-speed switching.

[0025] Secondly, due to the lack of an oil drainage mechanism, the lubricating oil in the friction interface is difficult to drain quickly, which hinders the separation process of the friction pair, prolongs the clutch response time, and reduces control precision and dynamic performance. This problem is particularly critical in applications with frequent start-stop or rapid gear shifting.

[0026] Furthermore, under high-speed conditions, the aforementioned oil film effect is further amplified: the increased centrifugal force makes it more difficult for the oil film to detach from the friction interface, the dragging torque increases nonlinearly, and at the same time, heat accumulation may form in local areas due to oil retention, which weakens the cooling efficiency of the lubrication system and forms a vicious cycle between "lubrication - heat generation - dragging".

[0027] To address the aforementioned issues, traditional possible solutions include: reducing the oil supply to decrease the oil film thickness during disengagement; adding oil drain grooves or centrifugal oil-throwing structures to the friction plates; and controlling the opening and closing of the lubrication circuit according to the clutch's operating state by setting up a lubrication control valve or spool valve structure, thereby reducing drag losses when the clutch is not in operation. However, these solutions still have significant drawbacks: reducing the oil supply sacrifices heat dissipation capacity during engagement, increasing the risk of thermal failure; passive oil drain structures are limited by geometric space and hydrodynamic characteristics, resulting in limited oil drain efficiency and difficulty in adapting to a wide speed range; while external lubrication control valves or spool valve structures increase system complexity, occupy space, and have a low degree of coupling between lubrication control and the clutch actuator, potentially introducing new reliability problems due to response delays or seal failures.

[0028] Furthermore, traditional shaft-driven oil supply structures typically employ axial oil passages near the outer wall of the input shaft or crankshaft to ensure sufficient mechanical strength for delivering lubricating oil to the friction pair area, which then enters the friction interface through small holes or gaps at the ends. However, due to the elongated oil passages and high flow resistance, this type of structure results in limited oil supply at the ends, making it difficult to achieve sufficient and uniform lubrication of all contact surfaces of the friction pair, which can easily lead to localized overheating and wear problems.

[0029] To solve the above problems, such as Figures 1-7 As shown, this application provides a centrifugal self-driven flow-controlled aviation friction clutch, including an input shaft 100, a housing 200 connected to the input shaft 100, a friction assembly 300 disposed within the housing 200, a piston cylinder 400 for pressing or releasing the friction assembly 300, an output shaft 500 cooperating with the friction assembly 300, and a lubrication mechanism; the lubrication mechanism includes: The oil supply shaft 610 is connected to the input shaft 100 and is provided with a lubrication oil passage. The lubrication oil passage is connected to the input shaft 100 and extends to the inner ring of the friction assembly 300. The flow channel control assembly 620 includes a control sleeve 621 movably sleeved on the oil supply shaft 610 and a linear drive member drivenly connected to the control sleeve 621. The linear drive member is controlled by the piston cylinder 400. The control sleeve 621 is provided with a through hole 6211. The linear drive member drives the control sleeve 621 to misalign or align the through hole 6211 with the port of the lubricating oil passage, so as to block or open the lubricating oil passage.

[0030] Compared with existing technologies, the centrifugal self-driven flow-controlled aviation friction clutch provided in this application, through the setting of a flow channel control component 620 linked with the piston cylinder 400, enables the lubrication mechanism to dynamically adjust the on / off state of the lubrication oil circuit according to the working state (engaged or disengaged) of the clutch: when the clutch is engaged, the through hole 6211 of the control sleeve 621 is aligned with the lubrication oil circuit to ensure that the friction pair receives sufficient lubrication and cooling; when the clutch is disengaged, the through hole 6211 is misaligned with the oil circuit, cutting off the lubrication oil supply, effectively reducing the formation of residual oil film between the friction plate 320 and the mating steel plate 310, thereby significantly reducing the drag torque, improving system efficiency, accelerating the lubrication oil discharge speed, shortening the response time, and enhancing control accuracy. Thus, by utilizing the existing drive component—piston cylinder 400—automatic switching of the oil supply logic is achieved without the need for an additional control system. While ensuring heat dissipation performance during engagement, it fundamentally alleviates the energy loss, dynamic interference, and heat accumulation problems caused by continuous oil supply in the disengaged state of traditional wet clutches, and comprehensively improves the operating stability and adaptability of the clutch in a wide range of operating conditions.

[0031] It should be noted that this application achieves linkage between lubrication supply and clutch operation. The lubrication mechanism does not provide continuous oil supply, but rather supplies oil on demand through a clever mechanical linkage design. Specifically, the oil supply shaft 610, connected to the input shaft 100, has an internal lubrication oil passage. The lubrication oil is primarily guided to the inner ring of the friction assembly 300 by the centrifugal force generated by the rotation of the oil supply shaft 610. The key control component is a control sleeve 621 fitted onto the oil supply shaft 610, which has a through hole 6211. This control sleeve 621 is driven by a linear drive, which is directly controlled by the piston cylinder 400 responsible for pressing the friction assembly 300.

[0032] When the clutch needs to engage to transmit power, the piston cylinder 400 is pushed by hydraulic oil to perform a clamping action. At the same time, the piston cylinder 400 drives the control sleeve 621 to move via a linear drive component, so that its through hole 6211 is precisely aligned with the port of the lubrication oil passage of the oil supply shaft 610, thereby opening the oil passage and allowing the lubricating oil to enter the friction pair for cooling and lubrication.

[0033] Conversely, when the clutch needs to disengage, the oil pressure in the piston cylinder 400 is released, causing the linear drive component to move the control sleeve 621 in the opposite direction. Its through-hole 6211 is misaligned with the lubrication oil circuit port, thus blocking the oil circuit. This cuts off the lubrication oil supply at its source, effectively preventing the generation of a large drag torque (pulling torque) due to lubrication oil stagnation between the friction pairs in the disengaged state. This significantly improves transmission efficiency and accelerates the separation process. It ensures sufficient lubrication when the clutch engages and timely oil cut-off when disengaging, perfectly resolving the contradictory needs of traditional wet clutches under different operating conditions.

[0034] In some possible implementations, the piston cylinder 400 includes a cylinder body 410 disposed at one end of the friction assembly 300, a first piston 420 disposed within the cylinder body 410 and attached to the friction assembly 300, and a first elastic reset structure 430 for resetting the first piston 420; the linear drive includes a second piston 622 disposed within the cylinder body 410 and arranged opposite to the first piston 420, and a second elastic reset structure 623 for resetting the second piston 622; the second piston 622 is connected to the control sleeve 621 via a piston rod.

[0035] Specifically, by integrating the piston cylinder 400 and the linear drive component into the same cylinder body 410, a highly compact structure and precise control linkage are achieved. Specifically, the cylinder body 410 has multiple circumferentially distributed hydraulic inlet holes 411. The first piston 420 is directly driven by hydraulic oil to press against the friction assembly 300, while the oppositely arranged second piston 622 serves as the drive source for the flow channel control assembly 620 and is directly connected to the control sleeve 621 via its piston rod. The two pistons are respectively reset by their independent first elastic reset structure 430 and second elastic reset structure 623. This system achieves fully mechanized synchronization between the clutch's operating state and lubrication supply: when hydraulic oil pushes the first piston 420 to engage the friction assembly 300, the oil pressure simultaneously acts on the second piston 622, overcoming its return spring force and driving the control sleeve 621 to move, aligning the through hole 6211 with the lubrication oil passage, thus initiating lubrication; conversely, when the system depressurizes, the first piston 420 and the second piston 622 reset under the action of their respective elastic return elements. The first piston 420 releases the friction assembly 300, while the second piston 622 pulls the control sleeve 621, causing its through hole 6211 to misalign with the port of the lubrication oil passage, quickly cutting off the lubrication oil supply. This not only eliminates the need for additional control mechanisms and simplifies the system, but more importantly, it ensures "on-demand" lubrication, eliminating the dragging torque caused by lubricating oil stagnation when the clutch is disengaged, significantly improving transmission efficiency and separation response speed.

[0036] It should be noted that during the engagement of the friction assembly 300, the through hole 6211 partially overlaps with the port of the lubrication oil passage to ensure the lubrication oil passage is open, allowing the lubricating oil to enter the engagement surface of the friction assembly 300 first, thus avoiding insufficient lubrication of the friction assembly 300. The second piston 622 pulling the control sleeve 621 to reset can quickly cut off the oil supply to the friction assembly 300, reduce the torque, and allow the friction assembly 300 to disengage more quickly and completely.

[0037] In this embodiment, the cylinder body 410 and the input shaft 100 are an integral structure. The cylinder body 410 serves as the end of the input shaft 100 closest to the housing 200. The cylinder body 410 and the housing 200 are fixedly connected by flanges and bolts. This detachable design of the cylinder body 410 and the housing 200 facilitates the installation and maintenance of the friction assembly 300. Furthermore, the piston chamber of the cylinder body 410 is annular. Both the first piston 420 and the second piston 622 are annular structures. The first elastic reset structure 430 can be composed of multiple circumferentially distributed springs or a single spring. The two ends of the spring are respectively positioned and engaged with the first end of the cylinder body 410 and the first piston 420. The second elastic reset structure 623 can also be composed of multiple circumferentially distributed springs or a single spring. The two ends of the spring are respectively positioned and engaged with the second end of the cylinder body 410 and the second piston 622.

[0038] In some possible implementations, the force required to push the second piston 622 is less than the force required to push the first piston 420, and the response speed of the control sleeve 621 is faster than the response speed of the friction assembly 300.

[0039] In one specific implementation, the effective pressure-bearing area of ​​the second piston 622 of the drive control sleeve 621 is designed to be significantly smaller than the effective pressure-bearing area of ​​the first piston 420 of the drive friction assembly 300. Since the hydraulic force F is equal to the system oil pressure P multiplied by the effective piston area A (F=P×A), under the same system control oil pressure, the smaller-area second piston 622 experiences less thrust, but its own mass is also generally lighter. More importantly, the stiffness of its matching second elastic reset structure 623 is designed to be lower than that of the first elastic reset structure 430 of the first piston 420. Therefore, when the system is pressurized, a smaller force can overcome the softer second elastic reset structure 623 to make the second piston 622 move quickly, causing the control sleeve 621 to open the oil circuit first; when the system is depressurized, the softer second elastic reset structure 623 can push the second piston 622 back more quickly, causing the control sleeve 621 to close the oil circuit first, thereby ensuring that lubrication control always precedes the physical engagement or disengagement of the friction pair.

[0040] In another specific implementation, through independent chambers and differentiated oil circuit damping design, the control sleeve 621 is made to act before the friction assembly 300 when the clutch engages and disengages. Specifically, the first piston 420 and the second piston 622 are placed in two independent hydraulic chambers controlled by the same oil source, and the oil circuit leading to the second piston 622 chamber is optimized. The inlet and outlet oil channels leading to the second piston 622 chamber are designed to be shorter and wider, with lower flow resistance; while the oil circuit leading to the first piston 420 chamber is relatively longer or has a throttling structure. Thus, at the moment the system is pressurized, the hydraulic oil can fill the second piston 622 chamber with less resistance and a faster speed, causing it to respond quickly and move the control sleeve 621; similarly, when the system is depressurized, the oil in the second piston 622 chamber can also be discharged more quickly, allowing it to return to its original position rapidly under the action of the return spring. This differentiated design through fluid dynamics paths ensures the action priority of the control sleeve 621 in the time dimension.

[0041] In other specific implementations, a lightweight and low-friction guiding structure ensures that the control sleeve 621 actuates before the friction assembly 300 during clutch engagement and disengagement. Specifically, the control sleeve 621 and its connected second piston 622 are designed as a lightweight structure, employing high-precision, low-friction guide seals, such as the PTFE composite sealing ring 130. Simultaneously, its stroke is designed to be shorter than that of the first piston 420. These measures collectively reduce the moment of inertia and frictional resistance of the second piston 622-control sleeve 621 assembly. Therefore, whether in hydraulic drive or elastic reset, the control sleeve 621 can complete its action with higher acceleration. During clutch engagement, the control sleeve 621 is the first to open the lubrication circuit; after the clutch disengagement command is issued, it is the first to cut off the oil circuit, perfectly achieving precise timing control of "lubrication first, oil cut-off priority," effectively solving the drag torque problem.

[0042] In some possible implementations, such as Figure 5 As shown, the oil supply shaft 610 has a central hole 611, a plurality of circumferentially distributed oil inlets 612 communicating with the oil inlet 110 of the input shaft 100, and a plurality of circumferentially distributed first oil-throwing holes 613 radially toward the inner ring of the friction assembly 300. The lubrication oil circuit includes the central hole 611, the oil inlets 612 and the first oil-throwing holes 613. The first oil-throwing holes 613 correspond to the through holes 6211 on the control sleeve 621.

[0043] Specifically, by integrating a central hole 611, a circumferential oil inlet hole 612, and a radial first oil slinger hole 613 on the oil supply shaft 610, a high-efficiency, short-range centrifugal force-driven lubrication path is constructed, effectively solving the lubrication problem of the aircraft tail thrust clutch under high power density and lightweight constraints. Specifically, on the one hand, it completely abandons the traditional oil bath immersion lubrication, significantly reducing the amount of lubricating oil used and the system weight, while eliminating the severe oil churning losses at high speeds; on the other hand, the input shaft and the oil supply shaft 610 rotate synchronously. When the clutch is engaged, the input shaft 100, output shaft 500, and oil supply shaft 610 rotate synchronously. Traditional clutches are also affected by centrifugal force when supplying oil, making it difficult for lubricating oil to enter the lubrication circuit. This application uses an oil supply shaft 610 with a large central hole 611 and multiple radially distributed oil inlets 612 on it. It is this structure that enlarges the lubrication circuit within a limited structural size, thereby solving the problem of insufficient oil volume in the lubrication circuit; furthermore, compared with the slender pipe oil supply method, this structure directly integrates the oil supply source into the rotating shaft, mainly using centrifugal force to actively throw the lubricating oil from the central hole 611 through the oil inlets 612 to the inner ring of the friction component 300. This not only significantly shortens the oil supply path and reduces flow resistance, but also achieves low dependence on external high-pressure oil sources. With the optimized design of the oil slinger shaft diameter and the number and distribution of oil slinger holes, it is further ensured that the lubricating oil can stably, evenly and sufficiently cover the entire friction pair under high speed conditions, fundamentally avoiding the risk of local lubrication failure and thermal decay, thus achieving the goal of high efficiency and high reliability lubrication within a limited space.

[0044] In this embodiment, lubricating oil enters the central hole 611 of the oil supply shaft 610 from the oil inlet 110 of the input shaft 100, and is then diverted through multiple circumferentially distributed oil inlets 612. It is then radially sprayed onto the inner ring of the friction assembly 300 through multiple circumferentially arranged first oil-throwing holes 613. The lubricating oil that has undergone heat exchange is discharged from the waist-shaped oil outlet 210 located on the outer side of the friction assembly 300 on the housing 200. Therefore, the centrifugal force generated by its own rotation facilitates lubrication circulation, ensuring uniform lubrication in the circumferential direction of the friction pair and effectively improving heat dissipation and wear conditions. Crucially, each first oil-throwing hole 613 corresponds one-to-one with a through hole 6211 on the control sleeve 621; when the control sleeve 621 moves under the drive of the second piston 622, its through holes 6211 can synchronously align with or offset all the first oil-throwing holes 613. This multi-hole collaborative design not only increases the flow area and reduces flow resistance, making lubrication supply more sufficient, but also, because the mating surfaces of the through hole 6211 and the oil slinger hole are cylindrical, the sealing and opening actions are more sensitive and reliable. This ensures that the lubrication circuit is fully open before the clutch engages and is completely cut off at the moment of disengagement, thereby achieving high-precision, low-hysteresis, and all-round on-demand lubrication control, further optimizing the transmission efficiency and service life of the clutch.

[0045] In some possible implementations, such as Figure 2 As shown in the figure, the arrows indicate the flow direction of the lubricating oil, and an annular groove 615 is provided between the oil inlet 110 and the oil inlet hole 612 of the input shaft 100.

[0046] Specifically, the annular groove 615 forms an annular pressure equalization cavity around the axis, which effectively buffers the fluctuation of external oil supply pressure, allowing the lubricating oil to be more evenly distributed to the multiple circumferentially distributed oil inlets 612, avoiding the failure of friction pair lubrication due to uneven local oil supply, and significantly improving the oil supply stability and adaptability of the lubrication system.

[0047] In some possible implementations, such as Figure 5 As shown, there are 4 to 8 oil inlet holes 612, with a diameter of 4 mm to 8 mm; the first oil slinger holes 613 are distributed in 3 rows along the axial direction of the oil supply shaft 610, with 4 to 8 holes in each row and a diameter of 1.2 mm to 1.8 mm.

[0048] Specifically, the design of the oil inlet hole 612 ensures sufficient lubricating oil flow into the central hole 611 while avoiding weakening the shaft strength due to excessively large openings. The design of the first oil-throwing hole 613 significantly increases the density of oil outlet points within a limited axial space, allowing the lubricating oil to more evenly cover the entire working area of ​​the inner ring of the friction assembly 300. The smaller diameter of the oil-throwing hole, combined with the strong centrifugal force generated by high speed, can form a high-speed micro-jet, enhancing the oil film formation capability and improving the cooling effect. At the same time, the multi-row, multi-hole structure effectively disperses local heat loads, preventing heat accumulation or lubrication blind spots caused by concentrated oil supply.

[0049] In some possible implementations, a sealing cap 616 is provided at the end of the oil supply shaft 610 away from the first oil slinger hole 613, and an elastic retaining ring 120 is embedded in the input shaft 100 abutting against the end of the oil supply shaft 610. The oil supply shaft 610 and the input shaft 100 are axially stepped. Sealing rings 130 are provided on both sides of the oil supply shaft 610 near the annular groove 615 and between the oil supply shaft 610 and the input shaft 100. The oil supply shaft 610 and the input shaft 100 are connected by spline drive or can be fixed by bolts.

[0050] Specifically, a sealing cap 616 is provided at the end of the oil supply shaft 610 away from the oil slinger hole to seal the end of the central hole 611 and prevent axial leakage of lubricating oil; the elastic retaining ring 120 embedded in the input shaft 100 abuts against the end of the oil supply shaft 610, providing axial preload while allowing slight thermal expansion displacement, avoiding structural jamming or seal failure due to thermal deformation; the oil supply shaft 610 and the input shaft 100 achieve precise axial positioning through axial steps to ensure accurate alignment of each oil hole with the annular groove 615; and the sealing rings 130 located on both sides of the annular groove 615 form a double sealing barrier to effectively prevent lubricating oil from flowing from the high-pressure oil inlet area to the non-working area.

[0051] In some possible implementations, such as Figure 5 As shown, one end of the oil supply shaft 610 is provided with a plurality of second oil-throwing holes 614 inclined toward the inner wall of the output shaft 500, and the inner wall of the output shaft 500 is provided with a plurality of third oil-throwing holes 510 distributed circumferentially.

[0052] Specifically, the second oil-throwing hole 614 is arranged at an angle along the axial end, so that the lubricating oil is sprayed at a certain angle onto the inner wall of the output shaft 500 under the action of centrifugal force. The lubricating oil is sprayed out through the third oil-throwing hole 510 to lubricate other components, and then enters the circulation.

[0053] In some possible implementations, such as Figure 6 As shown, the output shaft 500 has multiple circumferentially distributed grooves 520 on the surface of the inner ring of the friction assembly 300. Each groove 520 has multiple oil guide holes 530 that penetrate the output shaft 500 and are distributed along the axial direction. The inner wall of the output shaft 500 has a spacer 550 between the oil guide holes 530 and the third oil slinger hole 510 to prevent the lubricating oil from flowing back. The inner wall of the output shaft 500 and the outer wall of the oil supply shaft 610 have an annular gap to form an oil inlet cavity 540.

[0054] Specifically, the output shaft 500 has circumferentially distributed grooves 520 on the inner surface of the friction assembly 300. Each groove 520 contains multiple axially arranged oil guide holes 530, which effectively collect the centrifugally ejected lubricating oil and inject it into the friction area at multiple points along the axial direction. A spacer 550 is set between the oil guide holes 530 and the third oil ejection hole 510 to form a physical barrier, effectively preventing the ejected lubricating oil from flowing back to the oil supply chamber due to pressure difference or rotational disturbance, ensuring unidirectional flow of oil. At the same time, the output shaft 500 is connected to the inner side of the friction assembly 300 via a spline. The grooves 520 cleverly avoid the spline structure from obstructing the oil path, guiding the lubricating oil smoothly and evenly covering the mating surface of each friction plate 320 along a predetermined path. This not only solves the problem of lubrication blind spots caused by structural obstruction at high speeds, but also achieves further control of oil film distribution through the synergistic effect of multiple rows of oil guide holes 530 and grooves 520, significantly improving the cooling efficiency, anti-ablation ability, and engagement stability of the friction pair. The oil inlet chamber 540 and the spacer 550 work together to provide a stable and uniform circumferential flow channel for lubricating oil, and also effectively avoid the problem of uneven oil supply caused by the interference of rotational centrifugal force in traditional radial oil supply holes.

[0055] In one specific implementation, six rows of seven 2mm diameter oil guide holes 530 are opened at the position of the output shaft 500 corresponding to the friction component 300.

[0056] In some possible implementations, such as Figure 3 As shown, the friction assembly 300 includes a steel sheet 310, a friction plate 320, and a diaphragm spring 330. The steel sheet 310 and the friction plate 320 are stacked together, and the diaphragm spring 330 is disposed between two adjacent steel sheets 310 and surrounds the outer ring of the friction plate 320.

[0057] Specifically, the steel plate 310 is a ring-shaped steel structure, with its outer ring connected to the housing 200 via a spline, and rotates synchronously with the housing 200 under the drive of the input shaft 100; the friction plate 320 is a ring-shaped composite structure, with its main body being a steel structure and its surface covered with paper-based or copper-based materials, and its inner ring connected to the output shaft 500 via a spline, serving as the connection carrier for the output shaft 500; the main function of the diaphragm spring 330 is that when the clutch is disengaged, its preset elastic restoring force can actively push the adjacent steel plates 310 to separate, accelerating the disengagement action between the friction plate 320 and the steel plate 310, effectively avoiding dragging caused by residual friction or oil film adsorption; in addition, the diaphragm spring 330 also has the ability to buffer vibration and compensate for thermal deformation, maintaining the consistency of the friction pair clearance under high speed and high slip conditions, preventing local overheating or jamming. In some cases, the diaphragm spring 330 can replace the first elastic reset structure 430, or it can serve as a supplement to the first elastic reset structure 430.

[0058] In some possible implementations, such as Figure 7 As shown, the diaphragm spring 330 has an overall ring structure and a wave-shaped elastic structure along its circumference.

[0059] Specifically, the diaphragm spring 330 adopts an integral ring structure with a wavy elastic structure along the circumference. This not only ensures continuous support and uniform force distribution in the circumferential direction but also endows it with excellent axial elasticity and radial flexibility through its wavy profile. This structure enables the diaphragm spring 330 to generate stable and predictable elastic reaction force during axial compression, effectively assisting the friction plate 320 and the steel plate 310 to disengage quickly and synchronously. At the same time, the wavy elastic section can absorb impact loads and buffer torque fluctuations during clutch engagement, and maintain a constant clamping force even under minor axial displacements caused by thermal expansion or manufacturing tolerances, avoiding insufficient or excessive clamping. In addition, the continuous ring design eliminates the risk of off-center loading or misalignment that may occur with traditional split springs, improving dynamic balance performance and structural reliability under high-speed rotation.

[0060] In some possible implementations, the friction assembly 300 also includes an end retaining ring 340 for limiting the steel plate 310 located away from the first piston 420. The steel plate 310 located at the end is always in contact with the end retaining ring 340, effectively preventing axial movement or misalignment of the steel plate 310 due to inertia, oil pressure fluctuations, or the rebound of the elastic element during high-speed rotation of the clutch or frequent engagement / disengagement.

[0061] Those skilled in the art should understand that the discussion of any of the above embodiments is merely exemplary and is not intended to imply that the scope of protection of this application is limited to these examples; within the framework of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of one or more embodiments of this application as described above, which are not provided in detail for the sake of brevity.

[0062] One or more embodiments in this application are intended to cover all such substitutions, modifications, and variations that fall within the broad scope of this application. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of one or more embodiments in this application should be included within the protection scope of this application.

Claims

1. A centrifugal self-driven flow-controlled aircraft friction clutch, comprising an input shaft (100), a housing (200) connected to the input shaft (100), a friction assembly (300) disposed within the housing (200), a piston cylinder (400) for pressing or releasing the friction assembly (300), an output shaft (500) cooperating with the friction assembly (300), and a lubrication mechanism; characterized in that, The lubrication mechanism includes: The oil supply shaft (610) is connected to the input shaft (100) and has a lubrication oil passage. The lubrication oil passage is connected to the input shaft (100) and extends to the inner ring of the friction assembly (300). The flow channel control assembly (620) includes a control sleeve (621) movably sleeved on the oil supply shaft (610) and a linear drive member drivenly connected to the control sleeve (621). The linear drive member is controlled by the piston cylinder (400). The control sleeve (621) is provided with a through hole (6211). The linear drive member drives the control sleeve (621) to misalign or align the through hole (6211) with the port of the lubricating oil passage, so as to block or open the lubricating oil passage.

2. The centrifugal self-driven flow-controlled aviation friction clutch according to claim 1, characterized in that, The piston cylinder (400) includes a cylinder body (410) disposed at one end of the friction assembly (300), a first piston (420) disposed in the cylinder body (410) and attached to the friction assembly (300), and a first elastic reset structure (430) for resetting the first piston (420). The linear drive includes a second piston (622) disposed in the cylinder (410) and arranged opposite to the first piston (420), and a second elastic reset structure (623) for resetting the second piston (622); the second piston (622) is connected to the control sleeve (621) via a piston rod.

3. The centrifugal self-driven flow-controlled aviation friction clutch according to claim 2, characterized in that, The force required to push the second piston (622) is less than the force required to push the first piston (420), and the response speed of the control sleeve (621) is faster than the response speed of the friction assembly (300).

4. The centrifugal self-driven flow-controlled aircraft friction clutch according to any one of claims 1 to 3, characterized in that, The oil supply shaft (610) has a central hole (611), a plurality of circumferentially distributed oil inlets (612) communicating with the oil inlet (110) of the input shaft (100), and a plurality of circumferentially distributed first oil slingers (613) radially toward the inner ring of the friction assembly (300). The lubrication circuit includes the central hole (611), the oil inlets (612) and the first oil slingers (613), and the first oil slingers (613) correspond to the through hole (6211) on the control sleeve (621).

5. The centrifugal self-driven flow-controlled aviation friction clutch according to claim 4, characterized in that, An annular groove (615) is provided between the oil inlet (110) of the input shaft (100) and the oil inlet hole (612). And / or, the number of oil inlet holes (612) is 4 to 8, and the diameter is 4 mm to 8 mm; the first oil slinger holes (613) are distributed in 3 rows along the axial direction of the oil supply shaft (610), with 4 to 8 holes distributed circumferentially in each row, and the diameter is 1.2 mm to 1.8 mm.

6. The centrifugal self-driven flow-controlled aviation friction clutch according to claim 5, characterized in that, A sealing cap (616) is provided at the end of the oil supply shaft (610) away from the first oil throwing hole (613). An elastic retaining ring (120) is embedded in the input shaft (100) and abuts against the end of the oil supply shaft (610). The oil supply shaft (610) and the input shaft (100) are axially stepped together. Sealing rings (130) are provided between the two sides of the oil supply shaft (610) near the annular groove (615) and the input shaft (100).

7. The centrifugal self-driven flow-controlled aviation friction clutch according to claim 6, characterized in that, One end of the oil supply shaft (610) is provided with a plurality of second oil-throwing holes (614) inclined toward the inner wall of the output shaft (500), and the inner wall of the output shaft (500) is provided with a plurality of third oil-throwing holes (510) distributed circumferentially. The second oil-throwing holes (614) guide lubricating oil to be sprayed out to the inner cavity area of ​​the output shaft (500) where the third oil-throwing holes (510) are located.

8. The centrifugal self-driven flow-controlled aviation friction clutch according to claim 7, characterized in that, The output shaft (500) has a plurality of circumferentially distributed grooves (520) on the surface of the inner ring of the friction assembly (300). Each groove (520) has a plurality of oil guide holes (530) that penetrate the output shaft (500) and are distributed along the axial direction. The inner wall of the output shaft (500) has a spacer (550) between the oil guide holes (530) and the third oil sling hole (510) to prevent the backflow of lubricating oil. The inner wall of the output shaft (500) and the outer wall of the oil supply shaft (610) have an annular gap to form an oil inlet cavity (540).

9. The centrifugal self-driven flow-controlled aircraft friction clutch according to any one of claims 1-3 or 5-8, characterized in that, The friction assembly (300) includes a steel sheet (310), a friction plate (320), and a diaphragm spring (330). The steel sheet (310) and the friction plate (320) are stacked together, and the diaphragm spring (330) is disposed between two adjacent steel sheets (310).

10. The centrifugal self-driven flow-controlled aviation friction clutch according to claim 9, characterized in that, The diaphragm spring (330) has an overall ring structure and a wave-shaped elastic structure along its circumference.

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