A propeller with a pitch-changing mechanism

Abstract

The present invention relates to a propeller, specifically a propeller with a pitch-changing mechanism, comprising a blade assembly and a pitch-changing mechanism, the pitch-changing mechanism comprising 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 slidingly provided between the first support platform and the second support platform, an eccentric pin connected to the pitch-changing block being fixed 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 centerline of the pin hole, the end face of the blade assembly facing one end of the slider being in sliding engagement 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.

Description

Technical Field

[0001] The invention relates to a propeller, in particular to a propeller with a pitch-changing mechanism. Background Art

[0002] The propeller with a pitch-variable mechanism controls the rotation angle of the blades by setting a pitch-variable mechanism on the propeller. Specifically, the propeller includes a hub, a blade assembly and a pitch-variable mechanism. The blade assembly is rotatably mounted on the hub, and the pitch-variable mechanism is mounted on the hub. Figure 1 As shown, the pitch-changing mechanism generally includes a pitch-changing motor (not shown), a lead screw 6, and a slider. The lead screw 6 is connected to the pitch-changing motor, and the slider is threaded onto the lead screw 6. A pitch-changing block 3 is mounted on the slider in a direction perpendicular to the lead screw. The conventional slider includes a first block 1 and a second block 5. The first and second blocks 1 and 5 are separately mounted and fixed to each other by bolts 7. A first support platform 2 is fixed to the side of the first block 1 facing the blade assembly, which is used to transmit the force between the slider and the pitch-changing block 3. A second support platform 4 is fixed to the second block 5, which is opposite to the first support platform 2. The second support platform 4 is integrally formed with the second block 5. When the first and second blocks 1 and 5 are connected, the first and second support platforms 2 and 4 form a sliding groove on the side of the slider for the pitch-changing block 3 to slide. When the slider moves axially along the lead screw 6, the pitch-changing block 3 moves axially along the lead screw 6 under the action of the first and second support platforms 2 and 4. An eccentric pin is fixed to one end of the blade assembly, and a pin hole 31 that cooperates with the eccentric pin is provided on the pitch block 3. The blade assembly is inserted into the pin hole 31 of the pitch block through the eccentric pin, and the end of the blade assembly is clearance-matched with the slider. The blade assembly is used to limit the slider from rotating with the screw, and the pitch motor drives the screw to rotate, so that the slider and the screw rotate relative to each other and the slider slides along the axial direction of the screw. When the slider slides, the pitch block and the slider slide relative to each other, so that the pitch block drives the blade assembly and the hub to rotate relative to each other through the eccentric pin, thereby realizing the rotation of the blade assembly to a certain angle.

[0003] After mass production of such propellers, it was found that when used on fixed-wing drones, the drones were prone to pitch failure or serious deviations in the upper limit of the drone's flight altitude. Summary of the Invention

[0004] The purpose of the present invention is to provide a propeller with a pitch-changing mechanism to solve the problem in the prior art that fixed-wing UAVs are prone to pitch-changing failure or serious deviation in the upper limit of the flight altitude of the UAV.

[0005] In order to achieve the above-mentioned purpose, the basic scheme of the present invention provides a propeller with a pitch variable mechanism, including a blade assembly and a pitch variable mechanism, the pitch variable mechanism including a pitch variable motor, a screw and a slider, the slider is threadedly connected to the screw, a first support platform and a second support platform are provided on the slider, a pitch variable block is slidably arranged between the first support platform and the second support platform, an eccentric pin connected to the pitch variable block is fixed at the end of the blade assembly, the first support platform and the second support platform are both integrally formed with the slider, a limiting block is connected to the slider, the end of the limiting block is 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 slides with the limiting block.

[0006] The beneficial effect of this basic solution is that the first support platform and the second support platform are both integrally formed with the slider, eliminating the need for prior machining and subsequent assembly and connection between the first and second support platforms. Consequently, after the slider, first and second support platforms are machined, the size of the space between the first and second support platforms for the pitch-changing block to slide will no longer change. At the same time, the sliding fit between the stop block and the end face of the blade assembly reduces wear between the pitch-changing block and the slider. Compared to the prior art, this arrangement significantly reduces the incidence of pitch-changing failure or severe deviations in the upper limit of flight altitude in fixed-wing drones using the propeller of this solution.

[0007] Furthermore, the contact position between the stop block and the end face of the blade assembly is located on the side of the end face center away from the eccentric pin. This arrangement is beneficial to further extend the service life of the variable pitch motor and improve the working stability of the propeller.

[0008] Furthermore, the first support platform and the second support platform form a semi-through groove extending perpendicular to the direction of the lead screw on the side of the slider. This arrangement facilitates the assembly operation of the slider and surrounding related parts, thereby improving assembly convenience.

[0009] Furthermore, the pitch-changing block is provided with a pin hole for connecting with the eccentric pin of the blade assembly. Such a configuration facilitates the assembly and connection of the pitch-changing block and the eccentric pin. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 Schematic diagram of the cooperation structure of the slider and the lead screw in the pitch-changing mechanism of the propeller in the prior art;

[0011] Figure 2 A schematic diagram of an embodiment of a propeller with a pitch-changing mechanism according to the present invention;

[0012] Figure 3 for Figure 2 Schematic diagram of the matching structure between the middle slider and the lead screw. DETAILED DESCRIPTION

[0013] The following is further described in detail through specific implementation methods:

[0014] The reference numerals in the drawings of the specification include: slider 11, half-through slot 111, first support platform 12, second support platform 13, pitch change block 14, pin hole 141, limit block 15, screw 16, pitch change motor 17, blade assembly 18, and end face 181.

[0015] The embodiment is basically as shown in the attached Figure 2 and Figure 3 Figure 1 shows a propeller with a pitch-changing mechanism, comprising a hub (not shown), a blade assembly 18, and a pitch-changing mechanism. The blade assembly 18 is rotatably mounted on the hub, and the pitch-changing mechanism is mounted on the hub. The pitch-changing mechanism comprises a pitch-changing motor 17, a lead screw 16, and a slider 11. The pitch-changing motor 17 is fixedly mounted on the hub, and the lead screw 16 is in transmission connection with the pitch-changing motor 17. The slider 11 is fitted over the lead screw 16 and threadedly connected to the lead screw 16. A pitch-changing block 14 is slidably connected to the slider 11 in a direction perpendicular to the lead screw 16. An eccentric pin is connected to the end surface 181 of the blade assembly 18 facing the slider, which rotates with the pitch-changing block 14. Specifically, the pitch-changing block 14 is provided with a pin hole 141 that rotates with the eccentric pin. The eccentric pin is inserted into the pin hole 141, enabling relative rotation with the pitch-changing block 14. The end surface 181 of the blade assembly 18 is a circular plane.

[0016] The slider 11 is provided with a first support platform 12 and a second support platform 13. Both the first support platform 12 and the second support platform 13 are integrally formed with the slider 11. The first support platform 12 and the second support platform 13 form a semi-through groove 111 on the side of the slider 11, extending perpendicularly to the lead screw 16, so that the pitch-changing block 14 slides within the semi-through groove 111. The slider 11, the first support platform 12, and the second support platform 13 can be integrally formed by, for example, casting molten metal; of course, they can also be formed by removing material from a single piece of material, so that the first support platform 12 and the second support platform 13 are formed together with the slider 11. A limit block 15 is connected to the slider 11, and the limit block 15 is embedded in the slider 11. The end of the limit block 15 protrudes from the edge of the slider 11 in a direction parallel to the center line of the pin hole 141 and slides with the end face 181 of the blade assembly. The contact position between the limit block 15 and the end face 181 is located on the side of the center of the end face 181 away from the eccentric pin, so that the end of the blade assembly 18 will not contact the slider 11 under the support of the limit block 15, thereby avoiding mutual wear between the blade assembly 18 and the slider 11.

[0017] By adopting the solution of the present invention, the phenomenon of pitch change failure or serious deviation of the upper limit of flight altitude of fixed-wing UAVs using the propeller of this solution is greatly reduced, and the problems of pitch change failure or serious deviation of the upper limit of flight altitude of fixed-wing UAVs that often occur in the prior art are solved at the same time, thereby improving the quality stability of propellers with pitch change mechanisms produced in batches.

[0018] The above description is merely an embodiment of the present invention. Common knowledge regarding the specific structure and characteristics of the solution is not described in detail herein. It should be noted that those skilled in the art may make various modifications and improvements without departing from the structure of the present invention. These modifications and improvements should also be considered within the scope of protection of the present invention and will not affect the effectiveness of the implementation of the present invention or the practical application of the patent.

Claims

1. A propeller with a pitch-changing mechanism, comprising a blade assembly and a pitch-changing mechanism, wherein the pitch-changing mechanism comprises a pitch-changing motor, a lead screw, and a slider, wherein the slider is threadedly connected to the lead screw, a first support platform and a second support platform are provided on the slider, a pitch-changing block is slidably provided between the first and second support platforms, and an eccentric pin connected to the pitch-changing block is fixedly provided at the end of the blade assembly, characterized in that: The first support platform and the second support platform are both integrally formed with the slider, and a limit block is connected to the slider. The end of the limit block protrudes 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 slides with the limit block.

2. A propeller with a pitch-variable mechanism according to claim 1, characterized in that: The contact position between the limit block and the end face of the blade assembly is located on the side of the end face center away from the eccentric pin.

3. A propeller with a pitch-changing mechanism according to claim 1 or 2, characterized in that: The first support platform and the second support platform form a semi-through groove extending perpendicular to the direction of the lead screw on the side of the slider.

4. The propeller with a pitch-variable mechanism according to claim 3, characterized in that: The pitch-changing block is provided with a pin hole for connecting with the eccentric pin of the blade assembly.

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