A speed reduction device for an engine power turbine

Abstract

The present invention relates to the technical field of engines, and particularly to a speed reduction device for a power turbine of an engine. The power turbine includes a turbine shaft, and the speed reduction device includes: a static friction mechanism fixedly arranged inside the engine; a dynamic friction mechanism sleeved on the turbine shaft and rotating synchronously with the turbine shaft, and the dynamic friction mechanism is slidably matched with the turbine shaft along the axial direction of the turbine shaft; an actuating mechanism movably arranged inside the dynamic friction mechanism. When the turbine shaft is within a preset rotational speed, the actuating mechanism has a fixed state fixed inside the dynamic friction mechanism; when the turbine shaft reaches the preset rotational speed, the actuating mechanism has a movable state of sliding radially outward along the turbine shaft to trigger the contact and friction between the dynamic friction mechanism and the static friction mechanism; a separating mechanism connected to the turbine shaft and adapted to separate the dynamic friction mechanism and the static friction mechanism when the actuating mechanism is in the fixed state. It solves the technical problems of causing irreversible damage to the engine in the prior art and increasing the risk of secondary faults in the engine.

Description

Technical Field

[0001] The invention relates to the technical field of engines, and in particular to a speed reducer of an engine power turbine. Background Art

[0002] The aircraft engine power turbine shaft is an important component that outputs engine power to the outside and transmits power to the low-pressure compressor. Once a fault occurs or a break occurs, the engine will lose its ability to work and may even cause a serious safety accident. Therefore, turbine shaft speed or even breakage is a fatal fault and should be avoided as much as possible.

[0003] There are usually two types of solutions to the problem of the power turbine shaft speed surging, breaking the shaft and causing runaway. The first type is that the blades break automatically at the set speed. When the power turbine reaches the set critical breaking speed, the power turbine blades break under the action of strong centrifugal force, the structural integrity of the power turbine rotor is damaged, the working capacity decreases, and the speed automatically decreases. The second type is that the power turbine rotor and stator collide and wear, consuming the speed. After the power turbine shaft breaks, the turbine rotor moves toward the rear of the gas outlet under the action of the gas, and the rotor and stator come into contact to form intense friction, which decelerates under the action of collision and friction, preventing the rotor from running away. The above solutions will cause irreversible damage to the engine, increase the risk of secondary engine failures, and affect flight safety. Summary of the invention

[0004] The invention provides a deceleration device for an engine power turbine, which solves the technical problem that the prior art solution of decelerating a surge in turbine shaft speed will cause irreversible damage to the engine, increase the risk of secondary failure of the engine, and affect flight safety.

[0005] In view of this, the present invention provides a speed reducer for an engine power turbine, wherein the power turbine comprises a turbine shaft, and the speed reducer comprises:

[0006] A static friction mechanism, fixedly arranged inside the engine;

[0007] A dynamic friction mechanism is sleeved on the turbine shaft and rotates synchronously with the turbine shaft, and the dynamic friction mechanism is slidably matched with the turbine shaft along the axial direction of the turbine shaft;

[0008] an actuating mechanism, movably disposed in the dynamic friction mechanism, wherein when the turbine shaft is within a preset speed, the actuating mechanism has a fixed state in the dynamic friction mechanism; when the turbine shaft reaches the preset speed, the actuating mechanism has an active state in which it slides radially outwardly along the turbine shaft to trigger the dynamic friction mechanism to contact and rub with the static friction mechanism;

[0009] A separating mechanism, connected to the turbine shaft, is adapted to separate the dynamic friction mechanism from the static friction mechanism when the actuating mechanism is in the fixed state.

[0010] Optionally, the dynamic friction mechanism includes two friction discs;

[0011] The friction discs are sleeved on the turbine shaft, rotate synchronously with the turbine shaft, and are slidably connected to the turbine shaft;

[0012] The actuating mechanism is movably arranged between the two friction discs, and the actuating mechanism has the fixed state fixed between the two friction discs and the moving state for triggering the two friction discs to separate from each other;

[0013] The separating mechanism is adapted to drive the two friction discs to approach each other when the actuating mechanism is in the fixed state;

[0014] The static friction mechanism is sleeved on the outer peripheral edges of the two friction discs.

[0015] Optionally, the actuating mechanism includes a plurality of first sliding blocks;

[0016] On the opposite sides of the two friction discs, a plurality of reciprocating grooves are respectively recessed in the circumferential direction, and the reciprocating grooves on the two friction discs are correspondingly combined into a reciprocating cavity. The depth of the reciprocating grooves gradually becomes shallower from the inside to the outside along the radial direction of the friction discs;

[0017] The first sliding blocks are slidably arranged in the reciprocating cavity, and the two sides are respectively slidably matched with the bottoms of the two reciprocating grooves.

[0018] Optionally, a limiting mechanism is further included, arranged in the dynamic friction mechanism, for limiting the radial movement of the actuating mechanism when the turbine shaft is within the preset rotational speed.

[0019] Optionally, the limiting mechanism includes a plurality of limiting structures, and the limiting structures correspond to the first sliding blocks and are arranged in the friction discs;

[0020] The limiting structure includes a second sliding block, a third elastic member, and a retaining pin;

[0021] A first chute is arranged in the friction disc in the radial direction, and a second chute is arranged in the axial direction; the second chute is communicated with both the reciprocating groove and one end of the first chute close to the turbine shaft;

[0022] The second sliding block is slidably connected in the first chute, and a third elastic member is arranged between the second sliding block and the other end of the first chute;

[0023] One end of the second sliding block close to the turbine shaft is provided with an inclined member at a preset angle. A retaining pin is slidably connected in the second chute. The retaining pin is provided with a first locking hole adapted to the inclined member. Wherein, the inclined member inclines from the outside to the inside along the radial direction of the friction disc to the side away from the first sliding block;

[0024] A second locking hole corresponding to the retaining pin is provided on the first sliding block.

[0025] Optionally, a limiting projection for limiting the first sliding block is provided in the reciprocating groove. The limiting projection protrudes on the side of the reciprocating groove close to the turbine shaft.

[0026] Optionally, the separating mechanism includes a first separating structure and a second separating structure. The first separating structure and the second separating structure are respectively arranged on the opposite sides of the two friction discs. The first separating structure and the second separating structure are fixedly arranged on the turbine shaft and are used to drive the two friction discs to approach each other.

[0027] Optionally, the first separating structure includes a first elastic member and a first limiting member. The first limiting member protrudes on the turbine shaft. One end of the first elastic member abuts against the first limiting member, and the other end abuts against one of the friction discs;

[0028] The second separating structure includes a second elastic member and a second limiting member. The second limiting member is sleeved on the turbine shaft. One end of the second elastic member abuts against the second limiting member, and the other end abuts against the other friction disc.

[0029] Optionally, the first limiting member is an integrally formed annular protrusion;

[0030] And / or, the second limiting member is a nut. The nut is sleeved on the turbine shaft and is threadedly connected to the turbine shaft;

[0031] And / or, both the first elastic member and the second elastic member are corrugated springs. The corrugated springs are sleeved on the turbine shaft.

[0032] Optionally, the static friction mechanism includes a friction stator ring and a friction stator ring cover plate;

[0033] The friction stator ring cover plate is fixedly arranged inside the engine;

[0034] The friction stator ring is coaxially and fixedly connected to the friction stator ring cover plate. The friction stator ring and the friction stator ring cover plate cooperate to circumferentially wrap the two friction discs;

[0035] And / or, the friction disc is splined to the turbine shaft.

[0036] The technical solution of the present invention has the following advantages:

[0037] In the present invention, when the turbine shaft rotates within the preset speed, the actuating mechanism is in a fixed state, and the dynamic friction mechanism is separated from the static friction mechanism under the action of the separating mechanism. The dynamic friction mechanism rotates with the turbine shaft and does not affect the rotation of the turbine shaft. When the turbine shaft reaches the preset speed, under the action of centrifugal force, the actuating mechanism slides radially along the turbine shaft to trigger the movement of the dynamic friction mechanism. The dynamic friction mechanism overcomes the action of the separating mechanism and contacts the static friction mechanism. Since the static friction mechanism is fixed in the engine, the dynamic friction mechanism contacts the static friction mechanism in the rotating state to generate frictional force, which plays a role in decelerating, thereby reducing the speed of the turbine shaft and avoiding the risk of fracture due to excessive speed of the turbine shaft. When the speed of the turbine shaft drops below the preset speed, under the action of the separating mechanism, the dynamic friction mechanism is separated from the static friction mechanism, without affecting the rotation of the turbine shaft. The present invention decelerates the turbine shaft by triggering the contact between the dynamic friction mechanism and the static friction mechanism when the actuating mechanism reaches the preset speed, and can act repeatedly without causing irreversible damage to the engine, reducing the risk of secondary faults in the engine and improving the service life of the engine. Description of the Drawings

[0038] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0039] Figure 1 It is a schematic structural diagram of a deceleration device for an engine power turbine provided by the present invention;

[0040] Figure 2 is Figure 1 the A-A cross-sectional view in

[0041] Figure 3 is Figure 1 the partial enlarged view in

[0042] Explanation of the Reference Numerals:

[0043] 1. Turbine shaft; 2. Friction disc; 3. First limiting member; 4. First elastic member; 5. First sliding block; 6. Reciprocating groove; 7. Second sliding block; 8. Third elastic member; 9. Stop pin; 10. Inclined member; 11. First clamping hole; 12. Second clamping hole; 13. Limiting protrusion; 14. Friction stator ring; 15. Friction stator ring cover plate; 16. Spline; 17. Second limiting member; 18. First sliding groove; 19. Second sliding groove. Detailed Embodiments

[0044] The technical solution of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work shall fall within the protection scope of the present invention.

[0045] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0046] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0047] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0048] Embodiment 1

[0049] Please refer to Figures 1 to 3 , a deceleration device for an engine power turbine provided in this embodiment. The power turbine includes a turbine shaft 1. The deceleration device includes: a static friction mechanism fixedly arranged inside the engine; a dynamic friction mechanism sleeved on the turbine shaft 1 and rotating synchronously with the turbine shaft 1, and the dynamic friction mechanism is slidably matched with the turbine shaft 1 along the axial direction of the turbine shaft 1; an actuating mechanism movably arranged inside the dynamic friction mechanism. When the turbine shaft 1 is within a preset rotational speed, the actuating mechanism has a fixed state fixed inside the dynamic friction mechanism; when the turbine shaft 1 reaches the preset rotational speed, the actuating mechanism has a moving state of sliding radially outward along the turbine shaft 1 to trigger the contact and friction between the dynamic friction mechanism and the static friction mechanism; a separation mechanism connected to the turbine shaft 1 and adapted to separate the dynamic friction mechanism and the static friction mechanism when the actuating mechanism is in the fixed state.

[0050] The actuating mechanism refers to a mechanism that generates an action to cause other associated mechanisms to generate actions.

[0051] It should be noted that when the actuating mechanism is in a fixed state, the dynamic friction mechanism and the static friction mechanism are in clearance fit.

[0052] In this embodiment, when the turbine shaft 1 rotates within the preset speed, the actuating mechanism is in a fixed state. The dynamic friction mechanism is separated from the static friction mechanism under the action of the separating mechanism, and the dynamic friction mechanism rotates with the turbine shaft 1 without affecting the rotation of the turbine shaft 1. When the turbine shaft 1 reaches the preset speed, under the action of centrifugal force, the actuating mechanism slides radially along the turbine shaft 1 to trigger the movement of the dynamic friction mechanism. The dynamic friction mechanism overcomes the action of the separating mechanism and contacts the static friction mechanism. Since the static friction mechanism is fixed in the engine, the dynamic friction mechanism generates frictional force when contacting the static friction mechanism in the rotating state to play a decelerating role, thereby reducing the speed of the turbine shaft 1 and avoiding the risk of fracture due to excessive speed of the turbine shaft 1. When the speed of the turbine shaft 1 drops below the preset speed, under the action of the separating mechanism, the dynamic friction mechanism is separated from the static friction mechanism without affecting the rotation of the turbine shaft 1. By triggering the contact between the dynamic friction mechanism and the static friction mechanism at the preset speed by the actuating mechanism, the turbine shaft 1 is decelerated, and the action can be repeated multiple times without causing irreversible damage to the engine, reducing the risk of secondary faults of the engine, and improving the service life of the engine.

[0053] Embodiment 2

[0054] As a further improvement to Embodiment 1, as Figures 1 to 3 shown, the dynamic friction mechanism includes two friction discs 2; the friction discs 2 are sleeved on the turbine shaft 1, rotate synchronously with the turbine shaft 1, and are slidably connected to the turbine shaft 1; the actuating mechanism is movably arranged between the two friction discs 2, and the actuating mechanism has a fixed state fixed between the two friction discs 2 and an active state that triggers the two friction discs 2 to separate from each other; the separating mechanism is adapted to drive the two friction discs 2 to approach each other when the actuating mechanism is in a fixed state; the static friction mechanism is sleeved on the outer peripheral edge of the two friction discs 2.

[0055] In this embodiment, when the turbine shaft 1 is within the preset rotational speed, the two friction discs 2 approach each other under the action of the separating mechanism, and the actuating mechanism is fixed between the two friction discs 2. As the rotational speed of the turbine shaft 1 changes; when the preset rotational speed is reached, the centrifugal force increases, and under the action of the centrifugal force, the actuating mechanism slides radially along the friction disc 2, triggering the two friction discs 2 to slide axially along the turbine shaft 1. Furthermore, the two friction discs 2 come into contact with the static friction mechanism sleeved on the outer peripheral edges of the two friction discs 2, thereby generating frictional force to play a decelerating role. When the speed of the turbine shaft 1 drops to the preset rotational speed, the two friction discs 2 approach each other and separate from the static friction mechanism under the action of the separating mechanism. At the same time, the actuating mechanism returns to the fixed state by overcoming the centrifugal force under the action of the separating mechanism.

[0056] As an alternative embodiment, it can also be that the dynamic friction mechanism includes two friction discs 2; the friction discs 2 are sleeved on the turbine shaft 1, rotate synchronously with the turbine shaft 1, and are slidably connected to the turbine shaft 1; the actuating mechanism is movably arranged between the two friction discs 2, and the actuating mechanism has a fixed state fixed between the two friction discs 2 and a movable state that triggers the two friction discs 2 to separate from each other; the separating mechanism is adapted to drive the two friction discs 2 to approach each other when the actuating mechanism is in the fixed state; the static friction mechanism is arranged on one side where the two friction discs 2 face away from each other; wherein, the static friction mechanism includes a static friction disc, the static friction disc is fixedly arranged inside the engine, and the static friction disc rotates relative to the turbine shaft 1.

[0057] It should be noted that the static friction disc has a clearance fit with the friction disc 2 when the actuating mechanism is in the fixed state, and the static friction disc can be arranged on one side of any one of the friction discs 2.

[0058] In this embodiment, when the two friction discs 2 move away from each other under the action of the actuating mechanism, one of the friction discs 2 will come into contact with the static friction disc, thereby generating frictional force to decelerate.

[0059] On the basis of the above embodiment, in a specific embodiment, the actuating mechanism includes a plurality of first sliding blocks 5; a plurality of reciprocating grooves 6 are respectively recessed along the circumferential direction on one side where the two friction discs 2 face each other, and the reciprocating grooves 6 on the two friction discs 2 are correspondingly combined into a reciprocating cavity. The depth of the reciprocating groove 6 gradually becomes shallower from the inside to the outside along the radial direction of the friction disc 2; the first sliding blocks 5 are slidably arranged in the reciprocating cavity, and both sides are slidably matched with the bottoms of the two reciprocating grooves 6 respectively.

[0060] In this embodiment, since the depth of the reciprocating groove 6 gradually becomes shallower from the inside to the outside along the radial direction of the friction disk 2, the shape of the reciprocating cavity formed by the two reciprocating grooves 6 is narrower on the outside and wider on the inside along the radial direction of the friction disk 2. Therefore, when in the active state, when the first sliding block 5 slides outward in the reciprocating cavity along the radial direction of the friction disk 2 under the action of centrifugal force, it generates a force on the two reciprocating grooves 6 on both sides, causing the two friction disks 2 to tend to separate. When the preset rotational speed is reached, the force generated by the first sliding block 5 on the two friction disks 2 under the action of centrifugal force can overcome the force of the separation mechanism to drive the two friction disks 2 to slide and separate on the turbine shaft 1 and contact the static friction mechanism to decelerate.

[0061] On the basis of the above embodiment, in a specific embodiment, the first sliding block 5 is a wedge-shaped slider, and the reciprocating groove 6 is adapted to the inclined surface of the wedge-shaped slider.

[0062] It should be noted that the cross-section of the reciprocating groove 6 corresponding to the wedge-shaped slider is triangular.

[0063] In this embodiment, the wedge-shaped slider cooperates with the reciprocating groove 6 to slide, which is convenient for pushing the two friction disks 2 to separate in the active state and restoring to the fixed state under the action of the separation mechanism.

[0064] On the basis of the above embodiment, in a specific embodiment, a limiting mechanism is further included, which is arranged in the dynamic friction mechanism and is used to limit the movement of the actuating mechanism along the radial direction when the turbine shaft 1 is within the preset rotational speed.

[0065] In this embodiment, when the turbine shaft 1 is within the preset rotational speed (that is, when the actuating mechanism is in the fixed state), the limiting mechanism limits the movement of the actuating mechanism along the radial direction, avoiding the actuating mechanism generating a force on the two friction disks 2 under the action of centrifugal force and having a tendency to push the two friction disks 2 to separate within the preset rotational speed. At the same time, it avoids the actuating mechanism sliding along the radial direction due to the change in centrifugal force caused by the change in the rotational speed of the turbine shaft 1, improving the stability of the turbine shaft 1 when rotating within the preset rotational speed.

[0066] On the basis of the above embodiments, in a specific embodiment, the limiting mechanism includes a plurality of limiting structures, and the limiting structures correspond to the first sliding block 5 and are arranged in the friction disk 2; the limiting structure includes a second sliding block 7, a third elastic member 8 and a retaining pin; a first sliding groove 18 is provided in the friction disk 2 along the radial direction, and a second sliding groove 19 is provided along the axial direction; the second sliding groove 19 communicates with both the reciprocating groove 6 and one end of the first sliding groove 18 close to the turbine shaft 1; a second sliding block 7 is slidably connected in the first sliding groove 18, and a third elastic member 8 is provided between the second sliding block 7 and the other end of the first sliding groove 18; an inclined member 10 with a preset angle is provided at one end of the second sliding block 7 close to the turbine shaft 1, a retaining pin 9 is slidably connected in the second sliding groove 19, and a first clamping hole 11 adapted to the inclined member 10 is provided on the retaining pin 9, wherein the inclined member 10 is inclined from the outside to the inside along the radial direction of the friction disk 2 to the side away from the first sliding block 5; a second clamping hole 12 corresponding to the retaining pin 9 is provided on the first sliding block 5.

[0067] It should be noted that the elastic resistance of the preset third elastic member 8 corresponds to the acting force of the second sliding block 7 on the third elastic member 8 after being subjected to centrifugal force when the turbine shaft 1 reaches the preset rotational speed.

[0068] In this embodiment, when the first sliding block 5 is in a fixed state, the retaining pin 9 is clamped in the second clamping hole 12, and the inclined member 10 is clamped in the first clamping hole 11. When the turbine shaft 1 reaches the preset rotational speed, the second sliding block 7 slides along the first sliding groove 18 by overcoming the elastic resistance of the third elastic member 8 under the action of centrifugal force. At the same time, since the inclined member 10 is in contact with the first clamping hole 11, while the inclined member 10 moves with the second sliding block 7, it applies a force to the side of the first clamping hole 11 away from the first sliding block 5, causing the retaining pin 9 to move along the second sliding groove 19 to the side away from the first sliding block 5. Thus, the retaining pin 9 is disengaged from the first sliding block 5. After the first sliding block 5 is disengaged from the restriction of the retaining pin 9, it slides along the radial direction of the friction disk 2 under the action of centrifugal force. Furthermore, the first sliding block 5 pushes the two friction disks 2 to separate and contact the static friction mechanism to achieve deceleration. On the contrary, when the turbine shaft 1 decelerates to within the preset rotational speed, the centrifugal force received by the second sliding block 7 is less than the elastic resistance of the third elastic member 8. Then, under the elastic resistance of the third elastic member 8, the second sliding block 7 is pushed to move towards the turbine shaft 1 direction. Since the second clamping hole 12 on the first sliding block 5 is aligned with the retaining pin 9, when the inclined member 10 generates a force on the side of the first clamping hole 11 close to the first sliding block 5, it pushes the retaining pin 9 to move towards the first sliding block 5 direction, causing the retaining pin 9 to be clamped into the second clamping hole 12 of the first sliding block 5, restricting the radial sliding of the first sliding block 5 along the turbine shaft 1, and the first sliding block 5 returns to the fixed state, improving stability.

[0069] Specifically, limiting structures are arranged in both of the two friction disks 2 to further improve stability.

[0070] Specifically, the third elastic member 8 is a compression spring. One end of the compression spring abuts against the second sliding block 7, and the other end abuts against the bottom of the first sliding groove 18 away from one end of the turbine shaft 1, so as to drive the second sliding block 7 to move towards the turbine shaft 1 side.

[0071] Based on the above embodiment, in a specific embodiment, a limiting protrusion 13 for limiting the first sliding block 5 is arranged in the reciprocating groove 6. The limiting protrusion 13 protrudes on one side of the reciprocating groove 6 close to the turbine shaft 1.

[0072] In this embodiment, by arranging the limiting protrusion 13 in the reciprocating groove 6, when the first sliding block 5 moves radially towards the turbine shaft 1 to return to the fixed state, the movement of the first sliding block 5 is limited, so that when the first sliding block 5 moves to contact the limiting protrusion 13, the second engaging hole 12 is aligned with the second sliding groove 19, which is convenient for the retaining pin 9 to be engaged with the second engaging hole 12 for limiting.

[0073] Based on the above embodiment, in a specific embodiment, the separating mechanism includes a first separating structure and a second separating structure. The first separating structure and the second separating structure are respectively arranged on two opposite sides of the two friction discs 2. The first separating structure and the second separating structure are fixedly arranged on the turbine shaft 1 and are used to drive the two friction discs 2 to approach each other.

[0074] It should be noted that the driving forces of the first separating structure and the second separating structure on the friction disc 2 correspond to the acting forces applied to the friction disc 2 by the acting structure when it is subjected to centrifugal force. When the turbine shaft 1 reaches the preset rotational speed, the acting forces generated by the acting mechanism on the two friction discs 2 are respectively greater than the driving forces of the first separating structure and the second separating structure on the friction disc 2, so as to drive the two friction discs 2 to separate and slide on the turbine shaft 1.

[0075] In this embodiment, the first separating structure and the second separating structure are respectively arranged on two opposite sides of the two friction discs 2 and are used to drive the two friction discs 2 to approach each other. When the turbine shaft 1 is within the preset rotational speed, the first separating structure and the second separating structure located on both sides of the two friction discs 2 overcome the acting force of the acting mechanism on the friction disc 2, so as to drive the friction disc 2 to separate from the static friction mechanism and make the acting mechanism return to the fixed state.

[0076] Based on the above embodiment, in a specific embodiment, the first separating structure includes a first elastic member 4 and a first limiting member 3. The first limiting member 3 protrudes on the turbine shaft 1. One end of the first elastic member 4 abuts against the first limiting member 3, and the other end abuts against one friction disc 2; the second separating structure includes a second elastic member and a second limiting member 17. The second limiting member 17 is sleeved on the turbine shaft 1. One end of the second elastic member abuts against the second limiting member 17, and the other end abuts against the other friction disc 2.

[0077] It should be noted that the elastic forces of the first elastic member 4 and the second elastic member on the friction disc 2 correspond to the acting forces exerted on the friction disc 2 by the acting structure when subjected to centrifugal force. When the turbine shaft 1 reaches the preset rotational speed, the acting forces generated by the acting mechanism on the two friction discs 2 due to centrifugal force are respectively greater than the elastic forces of the first elastic member 4 and the second elastic member on the friction disc 2, so as to drive the two friction discs 2 to separate and slide on the turbine shaft 1.

[0078] In this embodiment, the first limiting member 3 and the second limiting member 17 are used as support points, and the first elastic member 4 and the second elastic member respectively abut against the two friction discs 2 to drive the two friction discs 2 to approach each other by using the elastic force as the driving force.

[0079] On the basis of the above embodiment, in a specific embodiment, the first limiting member 3 is an integrally formed annular protrusion.

[0080] In this embodiment, the annular protrusion is integrally formed with the turbine shaft 1, which has stronger rigidity and improves the service life.

[0081] On the basis of the above embodiment, in a specific embodiment, the second limiting member 17 is a nut, and the nut is sleeved on the turbine shaft 1 and is threadedly connected to the turbine shaft 1.

[0082] In this embodiment, by threadedly connecting the nut to the turbine shaft 1, it is convenient for disassembly and installation.

[0083] On the basis of the above embodiment, in a specific embodiment, both the first elastic member 4 and the second elastic member are corrugated springs, and the corrugated springs are sleeved on the turbine shaft 1.

[0084] In this embodiment, by using the corrugated spring as the driving force, the two friction discs 2 are driven to approach each other, and the corrugated spring is convenient for installation and disassembly.

[0085] As an alternative embodiment, it may also be that the separation mechanism includes a third separation structure. The third separation structure is arranged between the two friction discs 2, the third separation structure is fixedly arranged on the turbine shaft 1, and is used to drive the two friction discs 2 to approach each other; the third separation structure includes a third limiting member and a plurality of fourth elastic members. The third limiting member is fixedly arranged on the turbine shaft 1, and the fourth elastic members are symmetrically arranged on both sides of the third limiting member. One end of the fourth elastic member is connected to the third limiting member, and the other end is connected to the opposite sides of the two friction discs 2 (not shown in the figure).

[0086] It should be noted that the elastic force of the fourth elastic member on the friction disc 2 corresponds to the acting force exerted on the friction disc 2 by the acting structure when it is subjected to centrifugal force. When the turbine shaft 1 reaches the preset rotational speed, the acting mechanism is subjected to centrifugal force and the acting forces generated on the two friction discs 2 are respectively greater than the pulling force of the fourth elastic member on the friction disc 2, so as to drive the two friction discs 2 to separate and slide on the turbine shaft 1.

[0087] In this embodiment, the third limiting member is used as a support point, and the fourth elastic members on both sides of the third limiting member are respectively connected to the two friction discs 2 to drive the two friction discs 2 to approach each other by means of elastic pulling force as the driving force.

[0088] Specifically, the fourth elastic member is a tension spring.

[0089] On the basis of the above-mentioned implementation manner, in a specific implementation manner, the static friction mechanism includes a friction stator ring 14 and a friction stator ring cover plate 15; the friction stator ring cover plate 15 is fixedly arranged inside the engine; the friction stator ring 14 is coaxially and fixedly connected with the friction stator ring cover plate 15, and the friction stator ring 14 and the friction stator ring cover plate 15 cooperate to circumferentially cover the two friction discs 2.

[0090] It should be noted that when the first sliding block 5 is in a fixed state, both the friction stator ring 14 and the friction stator ring cover plate 15 are in clearance fit with the friction disc 2.

[0091] In this embodiment, when the two friction discs 2 slide along the turbine shaft 1 in opposite directions under the action of the acting mechanism, the two friction discs 2 respectively contact the inner side walls of the friction stator ring 14 and the friction stator ring cover plate 15 to generate frictional force for deceleration.

[0092] On the basis of the above-mentioned implementation manner, in a specific implementation manner, the friction disc 2 is connected to the turbine shaft 1 through a spline 16.

[0093] The spline 16 is divided into an internal spline (spline hole) and an external spline (spline shaft), and is a connecting member that connects the key and the shaft, and the keyway and the wheel into a whole, and can be either a fixed connection or a sliding connection.

[0094] In this embodiment, the turbine shaft 1 and the friction disc 2 are connected through the spline 16, so that the friction disc 2 can not only rotate with the turbine shaft 1, but also slide on the turbine shaft 1 to achieve deceleration.

[0095] Specifically, an external spline is provided on the turbine shaft 1, and an internal spline matching the external spline is provided at the axis center of the friction disc 2, and the external spline and the internal spline are connected in a matching manner.

[0096] In this embodiment, the specific working principle of the speed reduction device is as follows: When the turbine shaft 1 is within the preset rotational speed, at this time, the centrifugal force received by the second sliding block 7 is less than the elastic resistance of the third elastic member 8. The third elastic member 8 pushes the second sliding block 7 so that the inclined member 10 is clamped in the first clamping hole 11. The first sliding block 5 is fixed between the two friction discs 2 and the retaining pin 9 is clamped in the second clamping hole 12, and the first sliding block 5 does not slide. As the rotational speed of the turbine shaft 1 changes, when it reaches the preset rotational speed, the centrifugal force increases. Under the action of the centrifugal force, the second sliding block 7 overcomes the elastic resistance of the third elastic member 8 and slides along the first sliding groove 18. At the same time, since the inclined member 10 is in contact with the first clamping hole 11, when the inclined member 10 moves with the second sliding block 7, it exerts an action on the side of the first clamping hole 11 away from the first sliding block 5, causing the retaining pin 9 to move along the second sliding groove 19 away from the first sliding block 5. Thus, the retaining pin 9 disengages from the first sliding block 5. After the first sliding block 5 is released from the restriction of the retaining pin 9 and slides outward along the radial direction of the friction disc 2 in the reciprocating cavity under the action of the centrifugal force, it exerts a force on the reciprocating grooves 6 on both sides. At this time, the force exerted by the first sliding block 5 on the two friction discs 2 under the action of the centrifugal force can overcome the elastic forces of the first elastic member 4 and the second elastic member in the separation mechanism to drive the two friction discs 2 to slide on the turbine shaft 1 and separate in opposite directions. Then, the two friction discs 2 slide and respectively contact the inner side walls of the friction stator ring 14 and the friction stator ring cover plate 15 to generate frictional force, thereby reducing the speed of the turbine shaft 1. When the speed of the turbine shaft 1 decreases to within the preset rotational speed, the forces exerted by the first sliding block 5 on the reciprocating grooves 6 on both sides under the action of the centrifugal force are respectively less than the elastic forces exerted by the first elastic member 4 and the second elastic member on the two friction discs 2. Therefore, under the action of the first elastic member 4 and the second elastic member, the two friction discs 2 are driven to approach each other. The two friction discs 2 are separated from the inner side walls of the friction stator ring 14 and the friction stator ring cover plate 15 respectively. During the process of the two friction discs 2 approaching each other, the forces exerted by the reciprocating grooves 6 on both sides on the first sliding block 5 cause the first sliding block 5 to overcome the centrifugal force and slide along the reciprocating groove 6 towards the turbine shaft 1 until the first sliding block 5 abuts against the limiting protrusion 13. At this time, the second clamping hole 12 on the first sliding block 5 is aligned with the second sliding groove 19. At the same time, the centrifugal force received by the second sliding block 7 is less than the elastic resistance of the third elastic member 8. Then, under the elastic resistance of the third elastic member 8, the second sliding block 7 is pushed towards the turbine shaft 1. At this time, the inclined member 10 exerts an action on the side of the first clamping hole 11 close to the first sliding block 5, thereby pushing the retaining pin 9 to move along the second sliding groove 19 towards the first sliding block 5, causing the retaining pin 9 to be clamped into the second clamping hole 12 of the first sliding block 5 to restrict the radial sliding of the first sliding block 5 along the turbine shaft 1, and the first sliding block 5 returns to the fixed state. This solves the technical problem that the existing solution for reducing the speed of the sudden increase in the rotational speed of the turbine shaft 1 will cause irreversible damage to the engine, increase the risk of secondary failures of the engine, and affect the flight safety.

[0097] Obviously, the above embodiments are merely examples for clear illustration and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation manners here. And the obvious changes or modifications derived therefrom still fall within the protection scope of the present invention.

Claims

1. A speed reduction device for an engine power turbine, characterized in that, The power turbine includes a turbine shaft (1), and the reduction gear includes: A static friction mechanism fixedly arranged inside the engine; A dynamic friction mechanism sleeved on the turbine shaft (1), synchronously rotating with the turbine shaft (1), and the dynamic friction mechanism is slidably engaged with the turbine shaft (1) along the axial direction of the turbine shaft (1); An actuating mechanism movably arranged inside the dynamic friction mechanism. When the turbine shaft (1) is within a preset rotational speed, the actuating mechanism has a fixed state fixed inside the dynamic friction mechanism; when the turbine shaft (1) reaches the preset rotational speed, the actuating mechanism has a movable state of sliding radially outward along the turbine shaft (1) to trigger the dynamic friction mechanism to contact and friction with the static friction mechanism; A separating mechanism connected to the turbine shaft (1), adapted to separate the dynamic friction mechanism from the static friction mechanism when the actuating mechanism is in the fixed state; The dynamic friction mechanism includes two friction discs (2); The friction discs (2) are sleeved on the turbine shaft (1), synchronously rotate with the turbine shaft (1), and are slidably connected to the turbine shaft (1); The actuating mechanism is movably arranged between the two friction discs (2), and the actuating mechanism has the fixed state fixed between the two friction discs (2), and the movable state of triggering the two friction discs (2) to separate from each other; The separating mechanism is adapted to drive the two friction discs (2) to approach each other when the actuating mechanism is in the fixed state; The static friction mechanism is sleeved on the outer peripheral edge of the two friction discs (2); The actuating mechanism includes a plurality of first sliding blocks (5); On the opposite sides of the two friction discs (2) along the circumferential direction, a plurality of reciprocating grooves (6) are respectively recessed. The reciprocating grooves (6) on the two friction discs (2) correspond to form a reciprocating cavity, and the depth of the reciprocating grooves (6) gradually becomes shallower from the inside to the outside along the radial direction of the friction disc (2); The first sliding blocks (5) are slidably arranged in the reciprocating cavity, and the two sides are respectively slidably engaged with the bottoms of the two reciprocating grooves (6).

2. The speed reduction device for an engine power turbine according to claim 1, characterized in that, It further includes a limiting mechanism arranged inside the dynamic friction mechanism, used to limit the radial movement of the actuating mechanism when the turbine shaft (1) is within the preset rotational speed.

3. The speed reduction device for an engine power turbine according to claim 2, characterized in that, The limiting mechanism includes a plurality of limiting structures, and the limiting structures correspond to the first sliding blocks (5) and are arranged inside the friction disc (2); The limiting structure includes a second sliding block (7), a third elastic member (8) and a retaining pin (9); Inside the friction disc (2), a first sliding groove (18) is arranged radially, and a second sliding groove (19) is arranged axially; the second sliding groove (19) communicates with both the reciprocating groove (6) and the end of the first sliding groove (18) close to the turbine shaft (1); The second sliding block (7) is slidably connected in the first sliding groove (18), and a third elastic member (8) is arranged between the second sliding block (7) and the other end of the first sliding groove (18); One end of the second sliding block (7) close to the turbine shaft (1) is provided with an inclined member (10) at a preset angle. A retaining pin (9) is slidably connected in the second chute (19). A first clamping hole (11) adapted to the inclined member (10) is provided on the retaining pin (9). Wherein, the inclined member (10) is inclined from the outside to the inside along the radial direction of the friction disc (2) to the side away from the first sliding block (5); A second clamping hole (12) corresponding to the retaining pin (9) is provided on the first sliding block (5).

4. The speed reduction device for an engine power turbine according to claim 3, characterized in that, A limiting protrusion (13) for limiting the first sliding block (5) is provided in the reciprocating groove (6). The limiting protrusion (13) protrudes on the side of the reciprocating groove (6) close to the turbine shaft (1).

5. The speed reduction device for an engine power turbine according to any one of claims 1-4, characterized in that, The separating mechanism includes a first separating structure and a second separating structure. The first separating structure and the second separating structure are respectively arranged on two opposite sides of the two friction discs (2). The first separating structure and the second separating structure are fixedly arranged on the turbine shaft (1) and are used to drive the two friction discs (2) to approach each other.

6. The speed reduction device for an engine power turbine according to claim 5, characterized in that, The first separating structure includes a first elastic member (4) and a first limiting member (3). The first limiting member (3) protrudes on the turbine shaft (1). One end of the first elastic member (4) abuts against the first limiting member (3), and the other end abuts against one of the friction discs (2); The second separating structure includes a second elastic member and a second limiting member (17). The second limiting member (17) is sleeved on the turbine shaft (1). One end of the second elastic member abuts against the second limiting member (17), and the other end abuts against the other friction disc (2).

7. The speed reduction device for an engine power turbine according to claim 6, characterized in that, The first limiting member (3) is an integrally formed annular protrusion; The second limiting member (17) is a nut. The nut is sleeved on the turbine shaft (1) and is threadedly connected to the turbine shaft (1); Both the first elastic member (4) and the second elastic member are corrugated springs. The corrugated springs are sleeved on the turbine shaft (1).

8. The speed reduction device for an engine power turbine according to any one of claims 1-4, 6-7, characterized in that, The static friction mechanism includes a friction stator ring (14) and a friction stator ring cover plate (15); The friction stator ring cover plate (15) is fixedly arranged inside the engine; The friction stator ring (14) is coaxially and fixedly connected to the friction stator ring cover plate (15). The friction stator ring (14) and the friction stator ring cover plate (15) cooperate to circumferentially cover the two friction discs (2); The friction disc (2) is connected to the turbine shaft (1) through a spline (16).

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