A propeller centrifugal pitch device and pitch method

Abstract

The present invention discloses a centrifugal pitch device and pitch method for a propeller, comprising a housing, the housing being fixedly installed inside a propeller; a spring seat being in an inverted U shape and fixed at an inner hole on the housing; a bushing and a sealing ring being fixedly installed in the inner hole of the housing; a centrifugal pitch valve cooperating with the inner hole of the bushing; an inner ring of the spring penetrating the outer diameter of the centrifugal pitch valve, and the other end of the adjusting washer contacting with the spring seat; an oil circuit A and an oil circuit D being provided on the housing, an oil circuit hole B being provided on the bushing, a vertical through hole being provided in the middle of the centrifugal pitch valve to form an oil circuit G, and being communicated with a propeller oil return chamber; the centrifugal pitch valve being provided with a horizontal through hole, the horizontal through hole being cross-intersected and penetrating with the oil circuit G to form an oil circuit F; the centrifugal pitch valve cooperating with the inner hole of the bushing to form an oil circuit C. The centrifugal pitch device for a propeller provided by the present invention can complete oil circuit switching through the centrifugal force generated by its own parts, and realize the functions of pitching and releasing the pitch of the propeller, and has a simple structure.

Description

Technical Field

[0001] The present invention relates to the technical field of flight equipment, and more particularly to a propeller centrifugal pitch-fixing device and a pitch-fixing method. Background Art

[0002] At present, during the normal operation of a propeller aircraft, the propeller torque needs to be balanced with the output torque of the engine, and the propeller maintains a balanced speed.

[0003] However, when external conditions (such as flight altitude, flight speed) and the engine's output torque (change in fuel supply) change, the original torque balance is broken, which is directly manifested as a change in the propeller speed. The propeller changes the propeller pitch by switching the oil circuit through the control system to rebalance the torque and maintain the propeller's balanced speed. When the propeller pitch abnormally decreases, the speed exceeds the limit and cannot provide the thrust required for normal flight of the aircraft. At the same time, as the speed increases, the centrifugal force generated by the propeller rotation increases, which may exceed the strength limit of the propeller itself, causing accidents such as blade disengagement. The above two situations will directly affect the flight safety of the aircraft.

[0004] Therefore, how to provide a propeller centrifugal pitch device and pitch method is a problem that technical personnel in this field urgently need to solve. Summary of the invention

[0005] In view of this, the present invention provides a propeller centrifugal pitch device and method, which does not require a speed sensor to be set outside the propeller to measure the propeller speed, has low cost, is safe and reliable, and can achieve the effects of propeller pitch and release by generating centrifugal force through its own parts.

[0006] In order to achieve the above object, the present invention adopts the following technical solution:

[0007] A propeller centrifugal spacing device comprises a housing, a spring seat, a bushing, a sealing ring, an adjusting washer, a spring and a centrifugal spacing valve. The housing is fixedly installed inside the propeller and has an inner hole. The spring seat is in an inverted U shape and is fixed to the inner hole of the housing. The bushing and the sealing ring are fixedly installed in the inner hole of the housing. The centrifugal spacing valve cooperates with the inner hole of the bushing. The inner ring of the spring passes through the outer diameter of the centrifugal spacing valve, and one end of the spring abuts against the shaft shoulder of the centrifugal spacing valve, and the other end abuts against the end face of the adjusting washer. The other end of the adjusting washer contacts with the spring seat. There are oil circuit A and oil circuit D, an oil circuit hole B is opened on the bushing, a first annular groove is provided on the upper part of the bushing, and an oil circuit E is formed with the outer diameter of the centrifugal fixed-distance valve, a second annular groove is provided on the lower part of the bushing, and an oil circuit B is formed with the shell, a vertical through hole is provided in the middle part of the centrifugal fixed-distance valve, and an oil circuit G is formed, and is communicated with the propeller return oil chamber; the centrifugal fixed-distance valve has a horizontal through hole, and the horizontal through hole crosses and penetrates the oil circuit G to form an oil circuit F; the outer diameter of the centrifugal fixed-distance valve has an annular groove, and cooperates with the inner hole of the bushing to form an oil circuit C; the oil circuit C and the oil circuit E are separated by the shaft shoulder of the centrifugal fixed-distance valve.

[0008] Preferably, the shell is divided into an outer shell and an inner shell, the outer shell is a cylindrical steel part with a hollow interior, and the inner shell passes through the inner hole of the outer shell and is interference fit.

[0009] Preferably, the sealing ring includes a first sealing ring, a second sealing ring and a third sealing ring, and the first sealing ring, the second sealing ring and the third sealing ring are all fixedly installed in the inner hole of the inner shell; and the first sealing ring and the second sealing ring are provided with a first oil circuit ring groove and an oil circuit hole, and a second oil circuit ring groove and an oil circuit hole are provided between the second sealing ring and the third sealing ring.

[0010] Preferably, the first oil circuit ring groove oil circuit hole and the outer diameter of the centrifugal fixed-distance valve form an oil circuit E; the second oil circuit ring groove oil circuit hole and the inner shell form an oil circuit B.

[0011] The present invention also discloses a centrifugal pitch-fixing method for a propeller, which utilizes the centrifugal pitch-fixing device for a propeller, including an oil circuit A for high-pressure lubricating oil from an engine, which passes through an oil circuit B of a bushing, passes through an annular groove C formed by a centrifugal pitch-fixing valve and a bushing, and enters an oil circuit D. The high-pressure lubricating oil enters the interior of the propeller through the oil circuit D, and the propeller pitch-fixing clutch is opened, so that the normal pitch change of the propeller can be achieved; when the speed of the propeller exceeds a specified speed, the centrifugal pitch-fixing valve increases with centrifugal force, overcomes the elastic force of a spring, and moves upward, so that the oil circuit D is connected to the return oil circuit E in the centrifugal pitch-fixing valve. At this time, the propeller pitch-fixing clutch is closed because the high-pressure lubricating oil is connected to the return oil, and the propeller cannot continue to change the pitch, and the speed cannot continue to increase; when the speed decreases, the centrifugal pitch-fixing valve decreases with centrifugal force, and moves downward under the action of the spring elastic force, so that the oil circuit D is connected to the high-pressure lubricating oil A of the engine. At this time, the propeller pitch-fixing clutch is connected to the high-pressure lubricating oil, and the propeller can change the pitch normally.

[0012] It can be seen from the above technical solution that, compared with the prior art, the present invention discloses a propeller centrifugal pitch device, which is installed inside the propeller, and as the propeller rotates, the centrifugal force generated by the speed of the centrifugal pitch valve is balanced with the initial adjustment spring force of the spring, and the adjusting gasket can ensure the initial adjustment spring force of the spring, break the original balance state through the change of speed, and switch the oil circuit to achieve the function of propeller pitch and release. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0014] Figure 1 The accompanying drawing is a schematic structural diagram of the propeller centrifugal spacing device provided by the present invention.

[0015] Figure 2 The attached drawing shows the oil passage hole positions of the propeller centrifugal spacing device provided by the present invention.

[0016] Among them, the numbers in the figure are:

[0017] 1-spring seat, 2-adjusting washer, 3-spring, 4-centrifugal fixed distance valve, 5-bushing, 6-first sealing ring, 7-second sealing ring, 8-third sealing ring, 9-inner housing, 10-outer housing. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] like Figure 1 As shown, the embodiment of the present invention discloses a centrifugal distance device for a propeller, comprising a spring seat 1, an adjusting washer 2, a spring 3, a centrifugal distance valve 4, a bushing 5, a first sealing ring 6, a second sealing ring 7, a third sealing ring 8, an inner shell 9, and an outer shell 10. The device is located inside the propeller and rotates with the propeller.

[0020] The shell 9 is made of aluminum alloy, and the oil passage hole A and the oil passage hole D are pre-drilled inside. The shell 10 is a cylindrical steel part with a hollow interior. The outer diameter of the shell 9 passes through the inner hole of the shell 10 and forms an interference fit. After the interference fit installation of the shell 9 and the shell 10 is completed, the matching drilling is performed to form the inner hole for installing the bushing 5. The bushing 5, the first sealing ring 6, the second sealing ring 7, and the third sealing ring 8 are installed in the inner hole of the inner shell 9. The centrifugal spacing valve 4 is matched with the inner hole of the bushing 5 and is equipped with a spring 3. The inner diameter of the spring 3 passes through the outer diameter of the centrifugal spacing valve 4, one end of which rests on the shoulder of the centrifugal spacing valve 4, and the other end of which rests on the end face of the adjusting washer 2. The other end of the adjusting washer 2 contacts the spring seat 1. The spring seat 1 is connected to the outer shell 10 by bolts and compresses the spring 3.

[0021] like Figure 2 As shown, the first sealing ring 6, the second sealing ring 7, and the third sealing ring 8 are installed on the outside of the bushing 5, and are installed together in the inner shell 9. The middle part of the bushing 5 is a through hole, and the position between the first sealing ring 6 and the second sealing ring 7 is designed with a first oil circuit annular groove and an oil circuit hole, and the first oil circuit annular groove and the oil circuit hole form an oil circuit E with the outer diameter of the centrifugal fixed distance valve 4. The position between the second sealing ring 7 and the third sealing ring 8 of the bushing 5 is provided with a second oil circuit annular groove and an oil circuit hole, and the second oil circuit annular groove and the oil circuit hole cooperate with the shell 9 to form an oil circuit B. There is an elongated hole in the middle of the centrifugal fixed distance valve 4, which runs through the entire centrifugal fixed distance valve 4, forming an oil circuit G, and communicating with the propeller oil return chamber. The centrifugal fixed distance valve 4 has a through hole that crosses and runs through the oil circuit G in a "cross" shape, forming an oil circuit F. There is an annular groove on the outer diameter of the centrifugal fixed distance valve 4, which cooperates with the inner hole of the bushing 5 to form an oil circuit C. Oil circuit C and oil circuit E are separated by the shaft shoulder of the centrifugal fixed-distance valve 4.

[0022] The embodiment of the present invention also discloses a centrifugal pitch method for a propeller, wherein the oil circuit A is the high-pressure lubricating oil of the engine, which passes through the oil circuit hole B of the bushing 5, passes through the annular groove C formed by the centrifugal pitch valve 4 and the bushing 5, and enters the oil circuit D. The high-pressure lubricating oil enters the interior of the propeller through the oil circuit D, opens the propeller pitch clutch, and realizes normal pitch change of the propeller.

[0023] When the propeller speed exceeds the limited speed, the centrifugal fixed-pitch valve 4 moves upward under the centrifugal force, overcomes the spring force, and connects the oil circuit D with the oil return circuit E in the centrifugal fixed-pitch valve 4. At this time, the propeller fixed-pitch clutch is closed because the high-pressure lubricating oil is connected to the return oil, and the propeller cannot continue to change the pitch, and the speed cannot continue to increase. When the speed decreases, the centrifugal fixed-pitch valve 4 moves downward under the action of the spring 3 under the centrifugal force decreases, so that the oil circuit D is connected to the engine high-pressure lubricating oil A. At this time, the propeller fixed-pitch clutch is connected to the high-pressure lubricating oil, and the propeller can change the pitch normally.

[0024] The centrifugal force generated by the rotational speed of the centrifugal pitch valve 4 of the device is balanced with the initial adjustment spring force of the spring 3. The adjustment washer 2 can ensure the initial adjustment spring force of the spring 3. By changing the rotational speed, the original balance state is broken, the oil circuit is switched, and the propeller pitch is fixed and released.

[0025] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0026] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A propeller centrifugal pitch device, It is characterized in that The invention comprises a housing, a spring seat (1), a bushing (5), a sealing ring, an adjusting washer (2), a spring (3), and a centrifugal distance valve (4); the housing is fixedly installed inside the propeller and has an inner hole; the spring seat (1) is in an inverted U shape and is fixed to the inner hole of the housing; the bushing (5) and the sealing ring are fixedly installed in the inner hole of the housing; the centrifugal distance valve (4) is matched with the inner hole of the bushing (5); the inner ring of the spring (3) passes through the outer diameter of the centrifugal distance valve (4), and one end of the spring (3) abuts against the shaft shoulder of the centrifugal distance valve (4), and the other end abuts against the end face of the adjusting washer (2); the other end of the adjusting washer (2) contacts the spring seat (1); The shell is provided with an oil passage A and an oil passage D, the bushing (5) is provided with an oil passage hole B, the upper part of the bushing is provided with a first annular groove, and the oil passage E is formed with the outer diameter of the centrifugal fixed-distance valve (4), the lower part of the bushing (5) is provided with a second annular groove, and the oil passage B is formed with the shell, the middle part of the centrifugal fixed-distance valve (4) is provided with a vertical through hole, and the oil passage G is formed, and the oil passage G is communicated with the propeller oil return chamber; the centrifugal fixed-distance valve (4) is provided with a horizontal through hole, and the horizontal through hole and the oil passage G are cross-intersected and penetrated, and the oil passage F is formed; the outer diameter of the centrifugal fixed-distance valve (4) is provided with an annular groove, and the oil passage C is formed with the inner hole of the bushing; the oil passage C is separated from the oil passage E by the shaft shoulder of the centrifugal fixed-distance valve (4); The shell is divided into an outer shell (10) and an inner shell (9), the outer shell (10) is a cylindrical steel part with a hollow interior, and the inner shell (9) passes through the inner hole of the outer shell (10) and is interference fit; The sealing ring comprises a first sealing ring (6), a second sealing ring (7) and a third sealing ring (8), and the first sealing ring (6), the second sealing ring (7) and the third sealing ring (8) are all fixedly installed in the inner hole of the inner shell (9); and the first sealing ring (6) and the second sealing ring (7) are provided with a first oil path ring groove, and a second oil path ring groove is provided between the second sealing ring (7) and the third sealing ring (8).

2. A propeller centrifugal spacing device according to claim 1, It is characterized in that The first oil circuit annular groove and the outer diameter of the centrifugal fixed-distance valve (4) form an oil circuit E; the second oil circuit annular groove and the inner housing (9) form an oil circuit B.

3. A method for centrifugal pitch determination of a propeller, It is characterized in that The centrifugal pitch device of a propeller according to any one of claims 1 to 2 comprises an oil circuit A for high-pressure lubricating oil from the engine, which passes through an oil circuit B of a bushing (5), passes through an annular groove C formed by a centrifugal pitch valve (4) and a bushing (5), and enters an oil circuit D. The high-pressure lubricating oil enters the interior of the propeller through the oil circuit D, and the propeller pitch clutch is opened, so that normal pitch change of the propeller can be achieved; When the propeller speed exceeds the limited speed, the centrifugal pitch valve (4) moves upwards as the centrifugal force increases, overcoming the elastic force of the spring (3), so that the oil circuit D is connected to the oil return circuit E in the centrifugal pitch valve (4). At this time, the propeller pitch clutch is closed because the high-pressure lubricating oil is connected to the return oil, and the propeller cannot continue to change the pitch, and the speed cannot continue to increase; when the speed decreases, the centrifugal pitch valve (4) moves downwards under the action of the spring elastic force as the centrifugal force decreases, so that the oil circuit D is connected to the engine high-pressure lubricating oil A. At this time, the propeller pitch clutch is connected to the high-pressure lubricating oil, and the propeller can change the pitch normally.

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