An auxiliary starting device for helicopter engine

Abstract

The present invention is an engine auxiliary starting device, which is used to assist in starting an engine that is difficult to start with a load. The auxiliary starting device is connected to the rotor main shaft through a synchronous belt. The auxiliary starting device includes an inspiration integrated motor, a motor pulley, and a composite pulley. The output shaft of the inspiration integrated motor is provided with a motor pulley, and the motor pulley and the composite pulley are connected through a wedge belt; the composite pulley is provided on the output shaft of the engine, and an overrunning clutch is provided between the output shaft of the engine and the composite pulley. Compared with the prior art, the present invention first uses the inspiration integrated motor to start the rotor main shaft first, and then the engine joins the drive. For the engine, it omits the step of using the engine to start the rotor main shaft, so there is no need to install a clutch device, thereby firstly reducing the overall curb weight of the aircraft, and secondly, the device has a very low requirement for installation space and strong adaptability.

Description

Technical Field

[0001] The invention discloses a method for assisting the starting of an engine, which is used for assisting the starting of an engine that cannot be started with a load, and is particularly suitable for assisting the starting of a piston or rotor engine mounted on a helicopter, and includes its principle and mechanical structure. Background Art

[0002] Due to the fuel economy advantage, piston or rotary engines are widely used in the field of light and small helicopters. Due to the engine's own reasons, it is difficult to directly drive the helicopter rotor to rotate at the same time as starting, so a clutch device is designed between the engine and the rotor. This clutch device may be a mature clutch (such as a centrifugal clutch, electromagnetic clutch, hydraulic clutch, etc.), or it may be a belt tension drive device, such as a device that drives the tensioning steering wheel to change its position to achieve the tension of the drive belt, or directly changes the wheelbase between the engine output pulley and the driven pulley.

[0003] It can be assumed that piston or rotary engines will still be widely used in light and small helicopters for a long time in the future, and the need to achieve clutch between the engine and the load will exist for a long time. The current various clutch solutions all have some disadvantages.

[0004] Directly changing the wheelbase between the engine output pulley and the driven pulley can reduce the structural weight of the clutch device, but it has disadvantages such as complex engine hoisting and reliability risks of the driving servo. What's worse is that this solution causes a long period of relative slip between the belt and the pulley, causing serious wear of the belt or pulley, greatly increasing the risk of use and the burden of inspection and maintenance. The device that drives the tensioning steering wheel to change its position to achieve the tension of the drive belt can effectively simplify the installation of the engine, but the reliability risk of the tensioning drive motor has not been reduced at all, and the long period of relative slip also makes the risk of use and the burden of inspection and maintenance have not been improved. What's worse is that the device will increase the structural weight and have higher requirements for installation space.

[0005] Using a clutch to achieve clutching of the engine and load can fundamentally solve the problem of belt and pulley wear, but it seems to cause more problems than it solves. Centrifugal clutch is the most attractive option in this solution, but due to the low rotor speed of the helicopter, the centrifugal clutch is heavy, which invisibly increases the curb weight of the helicopter and affects the overall flight efficiency of the aircraft. Summary of the invention

[0006] The present invention aims to consider the helicopter as a whole, integrate the requirements, and assist the engine starting in a light, simple, reliable and safe manner.

[0007] The present invention is realized by the following technical means: an engine auxiliary starting device for a helicopter, the auxiliary starting device is connected to the rotor main shaft through a synchronous belt, the auxiliary starting device comprises an inspiration integrated motor, a motor pulley, and a composite pulley, a motor pulley is arranged on the output shaft of the inspiration integrated motor, and the motor pulley and the composite pulley are connected through a wedge belt;

[0008] The composite pulley is arranged on the output shaft of the engine, and an overrunning clutch is arranged between the output shaft of the engine and the composite pulley.

[0009] The auxiliary starting device is arranged on a bracket, and the bracket includes a support frame and an inspiration motor mounting frame. The support frame and the inspiration motor mounting frame are arranged perpendicular to each other. A synchronous pulley is arranged on the top of the support frame, and the synchronous pulley is connected to the rotor main shaft. A synchronous belt is arranged on the synchronous pulley and the motor pulley to connect and drive.

[0010] The initiating motor mounting frame is provided with mounting grooves for mounting the initiating integrated motor and the composite pulley.

[0011] It also includes a main reducer, the synchronous pulley is arranged on the input shaft of the main reducer, and the output part of the main reducer is connected to the rotor main shaft.

[0012] Compared with the prior art, the present invention first uses an integrated motor to start the rotor main shaft, and then the engine is used to drive it. For the engine, it eliminates the step of using the engine to start the rotor main shaft, so there is no need to install a clutch device, which firstly reduces the overall curb weight of the aircraft. Secondly, the device has low requirements for installation space and strong adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the application mode of the present invention on a helicopter;

[0014] Figure 2 Detailed schematic diagram of the engine auxiliary starting device;

[0015] Figure 3 It is a partial cross-sectional view of the engine auxiliary starting device.

[0016] Numbers in the figure: 1. Auxiliary starting device, 2. Synchronous belt, 3. Driven synchronous pulley, 4. Support frame, 5. Main reducer, 6. Rotor main shaft, 7. Engine output shaft interface, 8. Inspiration motor mounting frame, 9. Inspiration integrated motor, 10. Motor pulley, 11. Wedge belt, 12. Composite pulley, 13. Overrunning clutch. DETAILED DESCRIPTION

[0017] The present invention and its application in helicopter are further described in detail below:

[0018] The present invention relates to an auxiliary starting device for an engine, specifically, a device for auxiliary starting of a piston or rotor engine used on a light helicopter. The device is arranged on a set of conventional driving devices, that is, a bracket is arranged, a pulley and a driven synchronous pulley 3 are arranged on the bracket, the driven synchronous pulley 3 directly drives the rotor main shaft 6 of the helicopter, an engine output shaft interface 7 is arranged on the pulley, the pulley and the driven synchronous pulley 3 are connected by a synchronous belt 2, the engine directly drives the pulley to rotate, and then drives the driven synchronous pulley 3 to operate, the operation of the synchronous pulley drives the rotor main shaft 6 to operate, thereby realizing the operation of the helicopter.

[0019] The present invention is based on the original driving device, and provides a set of auxiliary starting device, and at the same time makes some improvements to the original conventional driving device. The auxiliary starting device is arranged at the same height as the pulley. Specifically, the auxiliary starting device includes an inspiration integrated motor 9, a motor pulley 10, and the motor pulley 10 is arranged on the output shaft of the inspiration integrated motor 9. The motor pulley and the pulley are connected by a wedge belt 11;

[0020] In the present invention, the pulley is a composite pulley 12, which is arranged on the output shaft of the engine, and an overrunning clutch is arranged between the output shaft of the engine and the composite pulley.

[0021] Furthermore, the bracket includes a support frame 4 and an inspiration motor mounting frame, and the support frame 4 and the inspiration motor mounting frame are arranged perpendicular to each other. A synchronous pulley 3 is arranged on the top of the support frame 4, and an installation groove for installing an inspiration integrated motor 9 and an installation groove for installing a composite pulley 12 is arranged on the inspiration motor mounting frame.

[0022] It also includes a main reducer 5 , the synchronous pulley 3 is arranged on the input shaft of the main reducer 5 , and the output part of the main reducer 5 is connected to the rotor main shaft 6 .

[0023] The present invention is described in detail below through specific examples:

[0024] Piston or rotor engines are usually difficult to drive the helicopter rotor to start. The present invention uses an inspiration motor 9 to drive the composite pulley 12 through a wedge belt 11, and then drives the driven synchronous pulley 3 to rotate through a synchronous belt 2, so as to pre-drive the rotor to rotate, and keep the rotor speed slightly higher than the rotor speed when the engine is idling, so as to achieve no-load starting of the engine driven by its own starting motor. After the engine is kept at the idle speed for a few seconds, it can enter the working speed according to the established procedure, and drive the inspiration motor 9 to switch to the generator mode in time. When the inspiration motor 9 drives the composite pulley 12, it will not drive the engine to rotate due to the action of the overrunning clutch 13.

[0025] The engine auxiliary starting device has high reliability. First, because the inspiration integrated motor 9 is used to slowly start the belt to rotate the rotor to a predetermined speed, and then the engine gradually drives the rotor, the whole process has little impact on the blades and the main reducer; secondly, the load is transmitted in a way without relative friction in the whole transmission path, so the wear is smaller; thirdly, the support frame 4 offsets the tension of the synchronous belt 2, so the tension of the synchronous belt 2 does not produce additional load on the body; in addition, the installation method of the engine is simpler after the auxiliary starting device is applied, which further improves the reliability of the system to a certain extent; finally, because the engine still retains the original starting motor, it can be completely changed to another inspiration integrated motor due to the small starting load, as a backup of the inspiration integrated motor 9, effectively ensuring that the power supply of the whole machine is more reliable.

[0026] The engine auxiliary starting device also has high safety. First, the system has high reliability. Second, if the engine stops due to a fault at high altitude, the system can use auto-glide to continue to generate electricity, ensuring the normal operation of the necessary onboard systems, and even allowing multiple attempts to start the engine.

[0027] The engine auxiliary starting device also has a lighter structural weight. This is because the clutch or steering wheel and its driving mechanism are eliminated, saving a part of the weight; secondly, after one speed increase, the rotation speed of the inspiration integrated motor 9 is greatly improved, which is beneficial to significantly reduce its weight; thirdly, since this scheme reduces the load on part of the body structure, it is beneficial to reduce the structural weight of the body; finally, two independent inspiration integrated motors are used to ensure the safety of the whole machine's electricity use, and even if the engine stops, the inspiration integrated motor 9 still has a certain power generation capacity, which can appropriately reduce the capacity of the helicopter's backup battery and effectively reduce the weight of the backup battery.

Claims

1. An engine auxiliary starting device for a helicopter, wherein the auxiliary starting device is connected to a rotor main shaft via a synchronous belt, and wherein: The auxiliary starting device comprises an inspiration integrated motor, a motor pulley, a composite pulley and a synchronous pulley. The motor pulley is arranged on the output shaft of the inspiration integrated motor, and the motor pulley and the composite pulley are connected by a wedge belt. The inspiration integrated motor, the motor pulley and the composite pulley are arranged at the same height. The composite pulley is arranged on the output shaft of the engine, and an overrunning clutch is arranged between the output shaft of the engine and the composite pulley; It also includes a main reducer, the synchronous belt pulley is arranged on the input shaft of the main reducer, the output part of the main reducer is connected to the rotor main shaft, and a synchronous belt is arranged on the synchronous belt pulley and the composite belt pulley for connection and driving.

2. The engine starting aid device according to claim 1, characterized in that: The auxiliary starting device is arranged on a bracket, and the bracket includes a supporting frame and an initiating motor mounting frame. The supporting frame and the initiating motor mounting frame are arranged perpendicular to each other, and a synchronous pulley is arranged on the top of the supporting frame; The initiating motor mounting frame is provided with mounting grooves for mounting the initiating integrated motor and the composite pulley.

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