Electric variable pitch propeller

Abstract

The invention discloses an electric variable-pitch propeller which comprises a blade assembly, a variable-pitch motor, a variable-pitch mechanism controlled by the variable-pitch motor and a driving device of the blade assembly, the variable-pitch mechanism comprises a sliding block provided with a sliding groove, a variable-pitch block is arranged in the sliding groove, and the variable-pitch block is connected with the blade assembly; wherein the variable-pitch motor is arranged at the end of the driving device. The vibration impact on the variable-pitch motor can be reduced, so that the damage of the variable-pitch motor caused by the vibration impact can be reduced, the service life of the variable-pitch motor is prolonged, and the reliability of the variable-pitch motor is improved; the variable pitch motor can be prevented from being directly exposed in the air, the influence of environmental factors on the variable pitch motor can be reduced, the service life of the variable pitch motor is further prolonged, the reliability of the variable pitch motor is further improved, and therefore the service life of the variable pitch propeller can be prolonged, and the variable pitch reliability of the variable pitch propeller can be improved.

Description

Technical Field

[0001] The invention relates to a variable pitch propeller, in particular to an electric variable pitch propeller for an aerial drone. Background Art

[0002] A variable pitch propeller is a propeller that can automatically (or manually) change the blade angle according to the flight speed and altitude during flight. When the inclination angle of each propeller blade changes, the output torque will also change, thereby changing the propeller thrust. During takeoff, the forward speed is low, and the variable pitch device reduces the propeller blade angle, so that the engine operates at maximum speed and maximum power, thereby allowing the propeller to produce maximum thrust. During level flight, the variable pitch mechanism can change the pitch to a high pitch propeller that is suitable for this flight state. At this time, the propeller can obtain the maximum useful power from the engine at the maximum speed. Therefore, the variable pitch propeller can utilize the maximum effective power of the engine at any flight speed. The electric variable pitch propeller refers to a variable pitch propeller whose blade rotation is driven by an electric motor.

[0003] The Chinese patent document CN116374159A of the prior art 1 discloses a propeller with a pitch-changing mechanism, including a blade assembly and a pitch-changing mechanism, the pitch-changing mechanism including a pitch-changing motor, a lead screw and a slider, the slider being threadedly connected to the lead screw, a first support platform and a second support platform being provided on the slider, a pitch-changing block being slidably provided between the first support platform and the second support platform, an eccentric pin connected to the pitch-changing block being fixedly provided at the end of the blade assembly, the first support platform and the second support platform being integrally formed with the slider, a limit block being connected to the slider, the end of the limit block being protruding from the edge of the slider in a direction parallel to the center line of the pin hole, and the end face of the blade assembly facing one end of the slider being slidably matched with the limit block. This solution solves the problem in the prior art that fixed-wing UAVs are prone to pitch-changing failure or serious deviations in the upper limit of the flight altitude of the UAV.

[0004] The Chinese patent document CN116788513A of prior art 2 discloses a rotor drive device including a turntable, a first drive motor, at least two second drive motors and an automatic tilt device; the drive unit of the first drive motor is connected to the turntable in a transmission manner, driving the turntable to rotate around its own axis, so that the blade clamp rotates synchronously with the turntable, thereby realizing that the blade rotates with the blade, and the blade is directly driven to rotate by the first drive motor, so that the drive device is smaller in size and lighter in weight, and is more suitable for the development needs of miniaturization and intelligence of aircraft. The second drive motor drives the automatic tilt device to move along the axial direction to adjust the total pitch of the propeller. The second drive motor drives the automatic tilt device to perform periodic horizontal tilting movements to adjust the periodic pitch. The aircraft provided in the embodiment of the present application also has the above-mentioned technical effects because it includes the above-mentioned rotor drive device.

[0005] In the prior art 1 and the prior art 2, the propeller pitch can be adjusted by driving the pitch-changing mechanism with a power motor to adapt to different flight altitudes, and the maximum effective power of the engine can also be effectively utilized. However, in actual flight, it is found that the pitch-changing function of the propeller is prone to failure, and the pitch cannot be changed, resulting in a large degree of waste of propeller power. Summary of the invention

[0006] In order to solve the technical problem that the pitch changing function of an electric propeller in the prior art is prone to failure, the present invention provides an electric variable pitch propeller, comprising a blade assembly, a pitch changing motor, a pitch changing mechanism controlled by the pitch changing motor, and a driving device of the blade assembly, wherein the pitch changing mechanism comprises a sliding block provided with a sliding groove, a pitch changing block is provided in the sliding groove, and the pitch changing block is connected to the blade assembly; wherein: the pitch changing motor is arranged at the driving device end.

[0007] In the prior art, there are many reasons for the failure of propeller pitch change, including motor failure, control system problems, mechanical failure, etc. Among them, the causes of motor failure usually include motor damage or overheating. After analyzing the causes of motor damage, it was found that the causes of motor damage currently known include poor motor heat dissipation, propeller blade damage, abnormal pitch motor voltage, etc. After solving the above reasons, it was found that the pitch motor is still prone to damage. After analysis, it was found that the pitch motor is currently installed inside the propeller and will rotate with the propeller. And because the propeller is a cantilever beam structure, and the pitch motor is located at the very end of the cantilever beam structure, the pitch motor is subjected to a large impact during the rotation of the propeller, which causes the pitch motor to be damaged.

[0008] Based on the above reasons, this solution adopts the method of placing the variable pitch motor at the end of the drive device. After the variable pitch motor is placed in the drive device, it is equivalent to placing the variable pitch motor outside the blade assembly, so it will not rotate with the propeller, but will be arranged on the propeller drive device as an external accessory of the propeller. Therefore, during the rotation of the propeller, the impact on the variable pitch motor will be reduced, so the damage to the variable pitch motor due to the impact will also be reduced. In the actual flight process, the probability of failure of the propeller pitch function can be reduced, so that the propeller can change pitch normally to ensure the normal flight of the aviation UAV.

[0009] Preferably, the drive device includes a stator, and the variable pitch motor is connected to the stator. In this solution, after the variable pitch motor is connected to the stator, on the one hand, the variable pitch motor can be set externally to the blade assembly, and on the other hand, the variable pitch motor can be set on the stator instead of the rotor to avoid the variable pitch motor rotating with the rotor, and can also reduce the impact of vibration shock on the variable pitch motor.

[0010] Preferably, the variable pitch motor is connected to the inner side of the stator and is arranged toward the inside of the drive device. In this solution, placing the variable pitch motor inside the drive device can prevent the variable pitch motor from being exposed to the air, reduce the impact of environmental factors on the variable pitch motor, and improve the service life and reliability of the variable pitch motor.

[0011] Preferably, the pitch-changing mechanism includes a first transmission member and a second transmission member, the first transmission member is connected to the output end of the pitch-changing motor, the second transmission member is mounted on the first transmission member and moves along the axial direction of the first transmission member, and the slider is connected to the second transmission member. In this solution, the rotation of the pitch-changing motor can be converted into the movement of the slider through the cooperation of the first transmission member and the second transmission member, thereby realizing the pitch-changing function, the structure is simple, and the manufacturing cost of the propeller can be reduced.

[0012] Preferably, the second transmission member is connected to the third transmission member, and the slider is connected to the second transmission member via the third transmission member. Considering that the distance between the variable pitch motor and the slider in the blade assembly will become longer after the variable pitch motor is externally arranged in the blade assembly, in this solution, after the third transmission member is arranged, a multi-stage transmission method is adopted, which can reduce the load of the variable pitch motor on the one hand, and facilitate the assembly of multiple transmission members on the other hand, and has a simple structure, which can reduce the cost of the variable pitch propeller.

[0013] Preferably, the variable pitch motor includes a motor housing. In this solution, the variable pitch motor can be protected by the motor housing, further reducing the impact of environmental factors on the variable pitch motor, and improving the service life and reliability of the variable pitch motor.

[0014] Preferably, the second transmission member is covered with a sleeve housing, and a limit assembly for limiting the radial rotation of the second transmission member is provided in the sleeve housing. In this solution, after the radial rotation of the second transmission member is limited by the limit assembly, it can be ensured that the second transmission member only moves axially, thereby ensuring the normal pitch change, the structure is simple, and the cost of the variable pitch propeller can be reduced.

[0015] Preferably, the limiting assembly includes a limiting block and a limiting groove that cooperates with the limiting block, the limiting groove is arranged on the inner wall of the sleeve housing, one end of the limiting block is connected to the second transmission member, and the other end of the limiting block is located in the limiting groove. In this solution, the radial rotation of the second transmission member is restricted by the cooperation between the limiting block and the limiting groove, the structure is simple, and the cost of the variable pitch propeller can be reduced.

[0016] Preferably, the blade assembly includes a hub and a guide rod located in the hub, the slider is located in the hub, and the guide rod axially penetrates the slider and is fixed to the inner wall of the hub. In this solution, the setting of the guide rod can make the slider only move axially, thereby ensuring the normal operation of the variable pitch function, with a simple structure, which can reduce the cost of the variable pitch propeller.

[0017] The present invention has the following beneficial effects: 1. The present invention can reduce the vibration impact on the variable pitch motor, thereby reducing the damage caused by the vibration impact on the variable pitch motor and extending the service life and reliability of the variable pitch motor.

[0018] 2. The present invention can prevent the variable pitch motor from being directly exposed to the air, and can also reduce the impact of environmental factors on the variable pitch motor, further improving the service life and reliability of the variable pitch motor, thereby improving the service life and pitch reliability of the variable pitch propeller.

[0019] 3. The present invention has a simple structure and can also reduce the manufacturing cost of the variable pitch propeller. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of an embodiment of an electric variable pitch propeller of the present invention; Figure 2 for Figure 1 A magnified schematic diagram of point B in the middle. DETAILED DESCRIPTION

[0021] The following is further described in detail through specific implementation methods: 1. Definition Variable pitch: refers to adjusting the pitch according to the flight status to ensure that the propeller obtains maximum useful power at maximum speed.

[0022] Pitch: refers to the inclination angle of the blade to the rotating plane when the helicopter rotor or fixed-wing propeller rotates 360 degrees.

[0023] 2. The reference numerals in the drawings of the specification include: cover plate 1, hub 2, slider 3, guide rod 4, rotor 5, motor housing 6, cover 7, stator 8, rolling bearing 9, third transmission member 10, connecting pin 11, second transmission member 12, bushing 13, sealing ring 14, bushing 15, limit block 16, sleeve housing 17, first transmission member 18, bearing 19, variable pitch motor 20.

[0024] The embodiment is basically as shown in the attached Figure 1 and Figure 2 As shown: an electric variable pitch propeller includes a blade assembly, a variable pitch motor 20, a variable pitch mechanism controlled by the variable pitch motor 20, and a driving device of the blade assembly, wherein the blade assembly includes a hub 2, a cover plate 1, and a guide rod 4 built into the hub 2. The variable pitch motor 20 is located on the right side of the hub 2, and an opening is provided on the left side of the hub 2, and the cover plate 1 is connected to the opening. The driving device includes a stator 8 and a rotor 5.

[0025] The pitch-changing mechanism comprises a first transmission member 18, a second transmission member 12, a third transmission member 10, a sleeve housing 17 and a slider 3 provided with a slide groove, a pitch-changing block is provided in the slide groove, the pitch-changing block is connected to the blade assembly, the slider 3 is located in the hub 2, and the guide rod 4 is fixed on the inner wall of the hub 2 after axially penetrating the slider 3. The pitch-changing motor 20 is provided with a motor housing 6 and a cover 7, and the pitch-changing motor 20 is wrapped by the motor housing 6 and the cover 7 and connected as a whole by locking screws. The pitch-changing motor 20 is located inside the drive device and fixed to the stator 8 of the drive device through the cover 7. The left end of the motor housing 6 is connected to the sleeve housing 17. The right end of the sleeve housing 17 is fixed to the hub 2 through the sleeve 15. The first transmission member 18 is connected to the output end of the pitch-changing motor 20, and the first transmission member 18 is supported and fixed inside the motor housing 6 and the sleeve housing 17 through the bearing 19.

[0026] The second transmission member 12 is sleeved on the left end of the first transmission member 18 and moves axially along the first transmission member 18. Specifically, a limit assembly for limiting the radial rotation of the second transmission member 12 is provided in the sleeve housing 17, and the limit assembly includes a limit block 16 and a limit groove matched with the limit block 16, and the limit groove is arranged on the inner wall of the sleeve housing 17, one end of the limit block 16 is connected to the second transmission member 12, and the other end of the limit block 16 is located in the limit groove.

[0027] The right end of the first transmission member 18 is connected to the output end of the variable pitch motor 20, the right end of the second transmission member 12 is covered on the left end of the first transmission member 18 and moves axially along the first transmission member 18, the second transmission member 12 is covered with a sleeve housing 17, and a limit assembly for limiting the radial rotation of the second transmission member 12 is provided in the sleeve housing 17, the limit assembly includes a limit block 16 and a limit groove matched with the limit block 16, the limit groove is provided on the inner wall of the sleeve housing 17, one end of the limit block 16 is connected to the second transmission member 12, and the other end of the limit block 16 is located in the limit groove. A bushing 13 and a sealing ring 14 are also provided on the inner wall of the sleeve housing 17 to support the second transmission member 12.

[0028] The right end of the second transmission member 12 is connected to the third transmission member 10 through the connecting pin 11, and the slider 3 is connected to the second transmission member 12 through the third transmission member 10. The slider 3 is fixed to the third transmission member 10 through the rolling bearing 9. Specifically, the first transmission member 18 is a lead screw, the second transmission member 12 is a threaded sleeve, and the third transmission member 10 is a pitch rod.

[0029] The specific implementation process is as follows: when in use, the DC power supply drives the variable pitch motor 20 to drive the first transmission member 18 to rotate, and since the sleeve housing 17 and the limit block 16 limit the circumferential displacement of the second transmission member 12, the second transmission member 12 moves axially along the first transmission member 18. The third transmission member 10 is connected to the second transmission member 12 through the connecting pin 11, so the movement of the second transmission member 12 drives the third transmission member 10 to move axially.

[0030] Since the third transmission rod is provided with a rolling bearing 9 connected to the slider 3, and the guide rod 4 passes through the slider 3 and is connected to the hub 2, there is no relative movement between the hub 2 and the slider 3 in the circumferential direction, and the guide rod 4 limits the third transmission member 10 to only axial movement. Therefore, the axial movement of the third transmission member 10 drives the slider 3 to move axially along the guide rod 4, thereby driving the blade assembly to achieve pitch change.

[0031] The above is only an embodiment of the present invention. The common sense such as the known specific structure and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field know all the common technical knowledge in the technical field of the invention before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, which will not affect the effect of the implementation of the present invention and the practicality of the patent. The protection scope required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. An electric variable pitch propeller, comprising a blade assembly, a variable pitch motor, a variable pitch mechanism controlled by the variable pitch motor, and a driving device of the blade assembly, wherein the variable pitch mechanism comprises a slider provided with a slide groove, a variable pitch block is provided in the slide groove, and the variable pitch block is connected to the blade assembly; characterized in that: The variable pitch motor is arranged at the end of the driving device.

2. The electric variable pitch propeller according to claim 1, characterized in that: The driving device comprises a stator, and the variable pitch motor is connected to the stator.

3. The electric variable pitch propeller according to claim 2, characterized in that: The variable pitch motor is connected to the inner side of the stator and is arranged toward the inside of the driving device.

4. The electric variable pitch propeller according to any one of claims 1 to 3, characterized in that: The pitch-changing mechanism comprises a first transmission member and a second transmission member, wherein the first transmission member is connected to the output end of the pitch-changing motor, the second transmission member is sleeved on the first transmission member and moves axially along the first transmission member, and the slider is connected to the second transmission member.

5. The electric variable pitch propeller according to claim 4, characterized in that: The second transmission member is connected to a third transmission member, and the slider is connected to the second transmission member through the third transmission member.

6. The electric variable pitch propeller according to claim 5, characterized in that: The variable pitch motor comprises a motor housing.

7. The electric variable pitch propeller according to claim 6, characterized in that: The second transmission member is covered with a sleeve housing, and a limiting component for limiting the radial rotation of the second transmission member is arranged in the sleeve housing.

8. The electric variable pitch propeller according to claim 7, characterized in that: The limiting assembly includes a limiting block and a limiting groove that cooperates with the limiting block, the limiting groove is arranged on the inner wall of the sleeve housing, one end of the limiting block is connected to the second transmission member, and the other end of the limiting block is located in the limiting groove.

9. The electric variable pitch propeller according to claim 8, characterized in that: The blade assembly comprises a hub and a guide rod located in the hub, the slider is located in the hub, and the guide rod axially penetrates the slider and is fixed on the inner wall of the hub.

Images