A propeller for a drone

Abstract

The present invention discloses a propeller for a drone, which comprises a hub and blades symmetrically arranged at both ends of the hub. The hub includes a hub main frame and a sleeve located inside the hub main frame. The hub main frame is connected to the sleeve through a rotating joint, and the rotating joint is arranged along the transverse axis of the propeller. The rotating joint includes a bushing and a pin. The axis of the bushing is arranged along the transverse axis of the propeller, and the pin is inserted into the bushing and can rotate around the axis of the bushing. The sleeve is coaxially and fixedly connected to the propeller rotating shaft. Variable pitch tie rods symmetrically arranged with respect to the transverse axis of the propeller are provided on the hub main frame. The variable pitch tie rods and the hub main frame are hinged through a first hinge shaft, and the first hinge shaft is parallel to the transverse axis of the propeller. For this propeller, the pitch of the blades at both ends of the hub main frame can be adjusted simultaneously only by the up-and-down floating of the variable pitch tie rods. The adjustment method is simple and easy to implement, and the driving structure only needs to drive the variable pitch tie rods, so the driving mechanism is greatly simplified.

Description

Technical Field

[0001] The present invention relates to the field of aviation technology, and particularly to a propeller for an unmanned aerial vehicle (UAV). Background Art

[0002] An unmanned aerial vehicle, abbreviated as UAV, is an unpiloted aircraft that is controlled by a radio remote control device and a self - contained program control device. In fact, UAVs are a general term for unpiloted aircraft. From a technical perspective, they can be classified into: unmanned fixed - wing aircraft, unmanned vertical take - off and landing aircraft, unmanned airships, unmanned helicopters, unmanned multi - rotor aircraft, unmanned parafoil aircraft, etc. Compared with manned aircraft, it has the advantages of small size, low cost, convenient use, low requirements for the combat environment, and strong battlefield survivability.

[0003] For a rotorcraft, in order to achieve flexible movement in the air, it is necessary to adjust the lift at various positions within the propeller rotation plane, that is, to adjust the pitch of the propeller. Subsequently, the propeller can generate driving forces in different directions for the aircraft. However, most of the current propeller pitch adjustment methods use separate drive mechanisms to individually adjust the propeller blades. This structural form not only has a complex structure and requires heavy drive mechanisms, but also it is not easy to control the combined torque matching between the blades.

[0004] In summary, how to solve the problems of inconvenient propeller pitch adjustment and the complex structure of the required drive mechanism has become a technical problem that needs to be urgently solved by those skilled in the art. Summary of the Invention

[0005] The purpose of the present invention is to provide a propeller for an unmanned aerial vehicle to solve the problems of inconvenient propeller pitch adjustment and the complex structure of the required drive mechanism.

[0006] To achieve the above purpose, the present invention provides a propeller for an unmanned aerial vehicle, which includes a hub and blades symmetrically arranged at both ends of the hub. The hub includes a main hub frame and a sleeve located inside the main hub frame. The main hub frame and the sleeve are connected by a rotating joint, and the rotating joint is arranged along the transverse axis of the propeller. The rotating joint includes bushings respectively fixedly arranged on both sides of the sleeve and two pin shafts arranged inside the main hub frame. The axis of the bushing is arranged along the transverse axis of the propeller, and the pin shaft is inserted into the bushing and can rotate around the axis of the bushing. The sleeve is coaxially and fixedly connected to the propeller shaft. The main hub frame is provided with variable - pitch tie rods symmetrically arranged about the transverse axis of the propeller. The variable - pitch tie rod and the main hub frame are hinged by a first hinge shaft, and the first hinge shaft is parallel to the transverse axis of the propeller.

[0007] Preferably, the blades of the propeller are respectively installed at both ends of the hub in a hinged manner.

[0008] Preferably, a blade mounting seat is further provided between the hub and the blade. One end of the blade mounting seat is hinged to the hub through a second hinge shaft, and the other end of the blade mounting seat is hinged to the blade through a third hinge shaft. Both the second hinge shaft and the third hinge shaft are perpendicular to the transverse axis of the propeller, and the second hinge shaft and the third hinge shaft are perpendicular to each other.

[0009] Preferably, the second hinge shaft is perpendicular to the plane where the main frame of the hub is located.

[0010] Preferably, the third hinge shaft is perpendicular to the plane where the main frame of the hub is located.

[0011] Preferably, the pin column includes a fixed column section and an insertion column section arranged coaxially with the fixed column section. Both sides of the fixed column section are connected to the inner side surface of the main frame of the hub through reinforcing rib plates; the insertion column section is inserted into the inner side of the sleeve and is rotatably connected to the sleeve.

[0012] Preferably, the pin column and the sleeve are connected through a bearing.

[0013] Preferably, the number of bearings provided between each pin column and the sleeve on its corresponding side is not less than 2.

[0014] Preferably, the pitch-changing pull rod includes a connecting column and hinge seats provided at both ends of the connecting column.

[0015] Preferably, the connecting column is threadedly connected to at least one of the hinge seats, and the depth of the connecting column screwed into the hinge seat is adjustable.

[0016] Compared with the content of the background art introduction, the above-mentioned propeller for a drone includes a hub and blades symmetrically arranged at both ends of the hub. The hub includes a main hub frame and a sleeve located inside the main hub frame. The main hub frame is connected to the sleeve through a rotating joint, and the rotating joint is arranged along the transverse axis of the propeller. The rotating joint includes bushings fixedly arranged on both sides of the sleeve and two pin columns arranged inside the main hub frame. The axis of the bushing is arranged along the transverse axis of the propeller, and the pin column is inserted into the bushing and can rotate around the axis of the bushing. The sleeve is fixedly connected coaxially with the propeller shaft. The main hub frame is provided with variable pitch tie rods symmetrically arranged with respect to the transverse axis of the propeller. The variable pitch tie rods and the main hub frame are hinged through a first hinge shaft, and the first hinge shaft is parallel to the transverse axis of the propeller. During the actual application of this propeller, by arranging a rotating joint between the main hub frame and the sleeve, and the rotating joint adopts the structural form of a pin column inserted into a bushing, therefore, the main hub frame can rotate relative to the sleeve around the transverse axis of the propeller. At the same time, since the sleeve is fixedly connected coaxially with the propeller shaft, the sleeve can also drive the main hub body to rotate together with the propeller shaft. When the propeller needs to change pitch, only need to drive the variable pitch tie rods symmetrically arranged on the main hub frame with respect to the transverse axis of the propeller, and the pitch of the blades at both ends of the main hub frame can be adjusted simultaneously by the up and down floating of the variable pitch tie rods. The adjustment method is simple and easy to implement, and the driving structure only needs to drive the variable pitch tie rods, so the driving mechanism is greatly simplified. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only 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.

[0018] Figure 1 Overall structural schematic diagram of the propeller for a drone provided by an embodiment of the present invention;

[0019] Figure 2 Structural schematic diagram of the propeller with a part of the blade removed provided by an embodiment of the present invention;

[0020] Figure 3 Top view structural schematic diagram of the propeller with a part of the blade removed provided by an embodiment of the present invention;

[0021] Figure 4 For Figure 3 A - A cross-sectional structural schematic diagram;

[0022] Figure 5 Structural schematic diagram of the reinforcing rib plate on one side of the pin column provided by an embodiment of the present invention;

[0023] Figure 6 Structural schematic diagram of the reinforcing rib plate on the other side of the pin column provided by the embodiment of the present invention;

[0024] Figure 7 Schematic diagram of the pitch change principle when the transverse axis of the propeller provided by the embodiment of the present invention is parallel to the X-axis;

[0025] Figure 8 Schematic diagram of the pitch change principle when the transverse axis of the propeller provided by the embodiment of the present invention is parallel to the Y-axis.

[0026] Upper Figures 1-8 In

[0027] Propeller hub 1, propeller hub main frame 1a, sleeve 1b, rotating joint 1c, bushing 1c1, pin column 1c2, bearing 1c3, propeller blade 2, propeller shaft 3, pitch change pull rod 4, connecting column 4a, hinge seat 4b, first hinge shaft 5, propeller blade mounting seat 6, second hinge shaft 7, third hinge shaft 8, reinforcing rib plate 9. Specific embodiments

[0028] The core of the present invention is to provide a propeller for an unmanned aerial vehicle to solve the problems that the pitch adjustment of the propeller is inconvenient and the required driving mechanism has a complex structure.

[0029] In order to enable those skilled in the art to better understand the technical solutions provided by the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0030] In the description of the present invention, it should be understood that if terms such as "upper", "lower", "front", "rear", "left" and "right" are involved to indicate the orientation or positional relationship, it 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 indicated position or element must have a specific orientation, be constructed and operated in a specific orientation, so it cannot be understood as a limitation of the present invention. In addition, if terms such as "first" and "second" are involved, they are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0031] Such as Figures 1-8As shown in the figure, a propeller for a drone provided by an embodiment of the present invention includes a hub 1 and blades 2 symmetrically arranged at both ends of the hub 1. The hub 1 includes a main hub frame 1a and a sleeve 1b located inside the main hub frame 1a. The main hub frame 1a and the sleeve 1b are connected by a rotating joint 1c, and the rotating joint 1c is arranged along the transverse axis of the propeller. The rotating joint 1c includes a bushing 1c1 fixedly arranged on both sides of the sleeve 1b and two pin posts 1c2 arranged inside the main hub frame 1a. The axis of the bushing 1c1 is arranged along the transverse axis of the propeller, and the pin post 1c2 is inserted into the bushing 1c1 and can rotate around the axis of the bushing 1c1. The sleeve 1a is fixedly connected coaxially with the propeller shaft 3. The main hub frame 1a is provided with pitch-changing tie rods 4 symmetrically arranged with respect to the transverse axis of the propeller. The pitch-changing tie rods 4 and the main hub frame 1a are hinged by a first hinge shaft 5, and the first hinge shaft 5 is parallel to the transverse axis of the propeller.

[0032] During the actual application process of this propeller, by arranging a rotating joint between the main hub frame and the sleeve, and the rotating joint adopts a structure form of a pin post inserted into a bushing. Therefore, the main hub frame can rotate relative to the sleeve around the transverse axis of the propeller. At the same time, since the sleeve is fixedly connected coaxially with the propeller shaft, the sleeve can also drive the main hub body to rotate together with the propeller shaft. When the propeller needs to change pitch, only need to drive the pitch-changing tie rods symmetrically arranged on the main hub frame with respect to the transverse axis of the propeller. By floating the pitch-changing tie rods up and down, the pitch of the blades at both ends of the main hub frame can be adjusted simultaneously. The adjustment method is simple and easy to implement, and the driving structure only needs to drive the pitch-changing tie rods, so the driving mechanism is greatly simplified.

[0033] For those skilled in the art to better understand the technical solution of the present invention, the following combines Figure 7 and Figure 8 to briefly describe the pitch-changing process of the propeller of the present invention:

[0034] The propeller shaft 3 drives the sleeve 1b, the main hub frame 1a and the blades 2 to rotate clockwise around the Z axis together. The control system performs periodic pitch-changing of the propeller through the pitch-changing tie rods 4. When the transverse axis of the propeller points in the Y-axis direction, the pitch-changing tie rods are in the initial position. When the transverse axis of the propeller points in the X-axis direction, one of the pitch-changing tie rods is pulled down and the other pitch-changing tie rod is pushed up, so that the leading edge of the blade at one end of the hub rises and the pitch angle increases; the trailing edge of the blade at the other end of the hub rises and the pitch angle decreases. This causes a lift difference between the two blades, and then generates a turning moment around the Y axis to realize the control of the drone.

[0035] In some specific embodiments, the blades 2 of the above-mentioned propeller are preferably installed at both ends of the hub 1 in a hinged manner respectively. Through the structural form of hinged connection, when the propeller rotates, the blades will be pulled until the transverse axis direction under the action of centrifugal force; when not flying, the propeller can be folded by folding the blades, so as to be able to reduce the overall occupied space of the aircraft and make storage more convenient.

[0036] In a further embodiment, a blade mounting seat 6 is further provided between the hub 1 and the blade 2. One end of the blade mounting seat 6 is hinged to the hub 1 through a second hinge shaft 7, and the other end of the blade mounting seat 6 is hinged to the blade 2 through a third hinge shaft 8. Both the second hinge shaft 7 and the third hinge shaft 8 are perpendicular to the transverse axis of the propeller, and the second hinge shaft 7 and the third hinge shaft 8 are perpendicular to each other. Through the arrangement of the above-mentioned blade mounting seat 6, the blades can swing and fold relative to the hub in two perpendicular planes, and then when the hub is inclined, the blades can also close to the propeller shaft for folding, which helps to reduce the volume after folding.

[0037] It should be noted here that in the actual application process, the second hinge shaft 7 can be designed to be perpendicular to the plane where the main frame 1a of the hub is located; the third hinge shaft 8 can also be designed to be perpendicular to the plane where the main frame 1a of the hub is located, which does not affect the normal storage and centrifugal expansion of the blades. In the actual application process, it can be selected according to actual needs.

[0038] In some more specific embodiments, the specific structure of the pin column 1c2 can include a fixed column section and an insertion column section arranged coaxially with the fixed column section. Both sides of the fixed column section can be connected to the inner side surface of the main frame 1a of the hub through a reinforcing rib plate 9; the insertion column section is inserted into the inner side of the bushing 1c1 and is rotatably connected to the bushing 1c1. By designing a segmented pin column structure, and the fixed column section is connected to the inner side surface of the main frame of the hub by a reinforcing rib plate, and the insertion column section is matched with the bushing, it helps to enhance the structural stability of the rotating joint. Holes for weight reduction can also be designed on the reinforcing rib plate. Of course, in order to ensure the uniform weight distribution of the whole hub, the holes for weight reduction generally need to be symmetrically arranged about the transverse axis of the propeller. In addition, the connection method between the reinforcing rib plate and the main frame of the hub can be selected as a welding connection method or an integrally injection-molded method, which can be selected according to actual needs in the actual application process.

[0039] In a further embodiment, in order to reduce the frictional resistance between the rotating joints, a bearing 1c3 is generally preferably used to connect the above-mentioned insertion column section 1c2 and the bushing 1c1. And in the actual application process, the number of bearings 1c3 provided between each pin column 1c2 and the bushing 1c1 on its corresponding side can be one or more, and is generally designed in a structural form of not less than 2. In the actual application process, the corresponding number of bearings can be selected according to actual needs, and no more specific limitations are made here.

[0040] In some more specific embodiments, the specific structure of the above-mentioned variable pitch tie rod 4 may include a connecting column 4a and hinge seats 4b provided at both ends of the connecting column 4a. By designing it into a double-hinge seat structure form, the installation and connection of the variable pitch tie rod are made more convenient.

[0041] In a further embodiment, in order to enhance the matching during the assembly of the variable pitch tie rod and avoid inaccurate variable pitch adjustment caused by processing errors, etc., at least one of the connecting column 4a and the hinge seat 4b is in threaded connection, and the depth of the connecting column 4a screwed into the hinge seat 4b is adjustable. Of course, it can also be designed that both ends of the connecting column are in threaded connection with the hinge seat. By means of threaded connection, the total length of the variable pitch tie rod can be adjusted by adjusting the depth of the connecting column screwed into the hinge seat, and then the assembly and debugging are made more convenient.

[0042] The above has introduced in detail the propeller for an unmanned aerial vehicle provided by the present invention. It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0043] It should also be noted that in this article, terms such as "including", "comprising" or any other variant thereof are intended to cover non-exclusive inclusion, so that an article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such article or device. Without more limitations, an element defined by the statement "including one..." does not exclude the existence of another identical element in the article or device including the above element.

[0044] Specific examples are used in this article to elaborate on the principles and implementation manners of the present invention. The description of the above embodiments is only used to help understand the core idea of the present invention. It should be pointed out that for those of ordinary skill in the art in this technical field, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A propeller for a drone, comprising a hub (1) and blades (2) symmetrically arranged at both ends of the hub (1), characterized in that, The hub (1) includes a main hub frame (1a) and a sleeve (1b) located inside the main hub frame (1a); the main hub frame (1a) is connected to the sleeve (1b) through a rotating joint (1c), and the rotating joint (1c) is arranged along the transverse axis of the propeller. The rotating joint (1c) includes bushings (1c1) respectively fixed on both sides of the sleeve (1b) and two pin posts (1c2) arranged inside the main hub frame (1a). The axis of the bushing (1c1) is arranged along the transverse axis of the propeller, and the pin post (1c2) is inserted into the bushing (1c1) and can rotate around the axis of the bushing (1c1); the sleeve (1b) is fixedly connected coaxially with the propeller shaft (3); a pitch-changing pull rod (4) symmetrically arranged about the transverse axis of the propeller is provided on the main hub frame (1a). The pitch-changing pull rod (4) and the main hub frame (1a) are hinged through a first hinge shaft (5), and the first hinge shaft (5) is parallel to the transverse axis of the propeller. The pin post (1c2) includes a fixed column section and an insertion column section arranged coaxially with the fixed column section. Both sides of the fixed column section are connected to the inner side surface of the main hub frame (1a) through reinforcing rib plates (9); the insertion column section is inserted inside the bushing (1c1) and is rotationally connected to the bushing (1c1). A bearing (1c3) is provided between the insertion column section and the bushing (1c1). The number of bearings (1c3) provided between each pin post (1c2) and the bushing (1c1) on its corresponding side is not less than 2. The pitch-changing pull rod (4) includes a connecting column (4a) and hinge seats (4b) arranged at both ends of the connecting column (4a). The connecting column (4a) is threadedly connected to at least one of the hinge seats (4b), and the depth of the connecting column (4a) screwed into the hinge seat (4b) is adjustable.

2. The propeller for a drone according to claim 1, characterized in that, The blades (2) of the propeller are respectively installed at both ends of the hub (1) in a hinged manner.

3. The propeller for a drone according to claim 2, wherein, A blade mounting seat (6) is further provided between the hub (1) and the blade (2). One end of the blade mounting seat (6) is hinged to the hub (1) through a second hinge shaft (7), and the other end of the blade mounting seat (6) is hinged to the blade (2) through a third hinge shaft (8). Both the second hinge shaft (7) and the third hinge shaft (8) are perpendicular to the transverse axis of the propeller, and the second hinge shaft (7) and the third hinge shaft (8) are perpendicular to each other.

4. The propeller for a drone according to claim 3, characterized in that, The second hinge shaft (7) is perpendicular to the plane where the main hub frame (1a) is located.

5. The propeller for a drone according to claim 3, wherein, The third hinge shaft (8) is perpendicular to the plane where the main hub frame (1a) is located.

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