Device for testing and calibrating pretightening force of folding paddle assembly

Abstract

The invention discloses a pretightening force testing and calibrating device for a folding paddle assembly. The pretightening force testing and calibrating device comprises the folding paddle assembly, a positive and negative rotation motor assembly, a testing base assembly and a force measuring assembly. The range of the pre-tightening force between the Teflon gasket of the folding paddle assembly and the folding paddle is tested and calibrated through the positive and negative rotation motor assembly and the force measuring assembly, so that the pre-tightening force generated by transition fit of the Teflon gasket and the folding paddle is moderate, and then when the folding paddle assembly works, the folding paddle can be normally unfolded under the action of centrifugal force; the initial vibration during unfolding can be reduced, and the abrasion of the Teflon gasket can be reduced when the paddle assembly works. According to the invention, the torsion range of the half-tooth screw is calibrated by adopting the electric inner hexagonal screwdriver capable of adjusting torsion, so that the batch production and installation of the folding paddle assembly are ensured, when the upper paddle clamp and the lower paddle clamp are tightened on the half-tooth screw, the pretightening force generated by the Teflon gasket and the folding paddle has better consistency, and the production efficiency is well improved.

Description

Technical Field

[0001] The present invention relates to the technical field of unmanned aerial vehicles, and specifically to a pre-tightening force testing and calibration device for a folding propeller assembly. Background Art

[0002] In recent years, unmanned aerial vehicles have achieved rapid development in various application fields such as aerial photography and entertainment, agricultural and forestry plant protection, inspection and surveying and mapping, emergency response, security, and material transportation and delivery. Folding propeller blades have the benefit of being easily stored and reducing the storage size space, and are often used in the power components of unmanned aerial vehicles. Among them, the Teflon gasket of the folding propeller blade assembly is used to reduce the frictional damage between the folding propeller blade and the upper propeller clamp and the lower propeller clamp. When the half-threaded screw of the folding propeller blade assembly tightens the upper propeller clamp and the lower propeller clamp, it is very difficult to ensure the consistency of the pre-tightening force between the Teflon gasket and the folding propeller blade.

[0003] For example: Propeller Clamp and Folding Propeller Structure (CN209553487U), this patent describes a propeller clamp structure that fixes the folding propeller blade through a double connecting shaft and uses a Teflon gasket to reduce friction, but does not involve pre-tightening force testing or calibration, and this patent only focuses on the mechanical structure design of the folding propeller.

[0004] Pre-tightening Force Calibration Device for High-strength Wind Power Bolts (CN117030094A), measures the axial pre-tightening force of the bolt through a transmission mechanism and a force-displacement sensor, and supports the calibration of bolts of different specifications. It is similar to the pre-tightening force calibration target of the present invention, but the application scenario is wind power bolts and the technical means are different (the user's patent triggers the pressure sensor by driving the propeller blade to rotate through a motor, rather than detecting the bolt deformation).

[0005] Therefore, it is necessary to design a device to measure and calibrate this pre-tightening force within a certain range, so that the pre-tightening force generated by the transitional fit between the Teflon gasket and the folding propeller blade is appropriate. At the same time, it is necessary to calibrate the tightening torque of the half-threaded screw to ensure that when the folding propeller blade assembly is mass-produced and installed, and the half-threaded screw tightens the upper propeller clamp and the lower propeller clamp, the pre-tightening force generated between the Teflon gasket and the folding propeller blade has good consistency, thereby improving production efficiency. Summary of the Invention

[0006] Based on the technical problems existing in the background art, the present invention proposes a pre-tightening force testing and calibration device for a folding propeller blade assembly.

[0007] A pre-tightening force testing and calibration device for a folding propeller blade assembly proposed by the present invention includes a folding propeller blade assembly, a forward and reverse rotation motor assembly, a test base assembly, and a force measuring assembly. The folding propeller blade assembly is connected to the forward and reverse rotation motor assembly, and the folding propeller blade assembly and the forward and reverse rotation motor assembly are installed on the test base assembly. The force measuring assembly is connected to the forward and reverse rotation motor assembly, and the forward and reverse rotation motor assembly drives the folding propeller blade assembly to rotate, thereby realizing the dynamic testing and calibration of the pre-tightening force through the force measuring assembly.

[0008] The folding paddle assembly includes folding blades, Teflon gaskets, half-thread screws, upper paddle clamps, and lower paddle clamps. There are four Teflon gaskets in total, which are respectively placed between the folding blades and the upper paddle clamps, and between the folding blades and the lower paddle clamps. The half-thread screws pass through the hole positions of the upper paddle clamps, the hole positions of the Teflon gaskets, the hole positions of the folding blades, then pass through the hole positions of the lower Teflon gaskets, and are connected to the threaded hole positions of the lower paddle clamps;

[0009] The forward and reverse motor assembly includes an adapter, mounting adapter screws, and a forward and reverse motor. The adapter is provided with guide posts, which are used for quickly guiding and placing the folding paddle assembly during the pre-tightening force test.

[0010] The test base assembly includes a base, brackets, and a storage housing. There are four brackets symmetrically distributed horizontally and two storage shelves symmetrically distributed vertically. The brackets and the storage housing are both installed on the base by screws.

[0011] The force measuring assembly includes pressure sensors and a pressure gauge display. The pressure sensors are installed on the brackets by screws and are symmetrically distributed four horizontally. The pressure gauge display is placed on the storage housing and is symmetrically distributed two vertically.

[0012] Preferably, the Teflon gaskets are used to buffer the frictional damage between the folding blades and the upper and lower paddle clamps when the folding blades rotate.

[0013] Preferably, when the upper and lower paddle clamps are tightened by the half-thread screws, the tolerance fit between the Teflon gaskets and the folding blades should be a transition fit, thereby generating a certain pre-tightening force.

[0014] Preferably, the forward and reverse motor is set with a forward and reverse angle range of -45° to 45°, and is set to rotate at a constant speed of 15 rpm in both forward and reverse directions.

[0015] Preferably, the forward and reverse motor drives the folding paddle assembly to rotate through the guide posts provided on the adapter, and then drives the folding blades to rotate around the smooth rod part of the half-thread screws. When the tip of the folding blade touches the pressure sensor, the pressure gauge display shows the pre-tightening force generated by the transition fit between the Teflon gasket and the folding blade.

[0016] Preferably, an electric hexagon screwdriver with adjustable torque is used to adjust the tightening degree of the half-thread screws, and the folding paddle assembly is driven to rotate forward and backward by the forward and reverse motor, so that the pressure gauge display shows that the test display pre-tightening force range between the Teflon gasket and the folding blade is 40 - 60 g, and the difference in pre-tightening force between the two blades should be less than 10 g, so that the pre-tightening force generated by the transition fit between the Teflon gasket and the folding blade is appropriate. Thus, when the folding blade assembly works, the folding blades can be normally unfolded by the action of centrifugal force, and the initial vibration during unfolding can be reduced, and the wear of the Teflon gasket during the operation of the blade assembly can also be reduced.

[0017] Preferably, after adjusting the tightening degree of the half-thread screw with an electric hexagon screwdriver with adjustable torque, calibrate the torque of the electric hexagon screwdriver. The calibrated torque range is 0.18 ± 0.02 N·m, so as to ensure that when mass-producing and installing the folding paddle assembly, when tightening the upper paddle clamp and the lower paddle clamp with the half-thread screw, the pre-tightening force generated between the Teflon gasket and the folding paddle blade is basically the same.

[0018] Preferably, a high-strength thread sealant needs to be applied to the threaded part of the half-thread screw to prevent the half-thread screw from falling off due to the vibration generated during the operation of the folding paddle assembly. Then, use an electric hexagon screwdriver with a calibrated torque range of 0.18 ± 0.02 N·m to tighten the half-thread screw with the high-strength thread sealant together with the upper paddle clamp, the Teflon gasket, the folding paddle blade and the lower paddle clamp.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0020] 1. The present invention tests and calibrates the pre-tightening force range between the Teflon gasket and the folding paddle blade of the folding paddle assembly through the forward and reverse rotation motor assembly and the force measuring assembly. The specific range is 40-60 g, and the difference in the pre-tightening force between the two paddle blades needs to be less than 10 g, so that the pre-tightening force generated by the transitional fit between the Teflon gasket and the folding paddle blade is moderate. When the folding paddle blade assembly is working, the folding paddle blade can be normally unfolded by the action of centrifugal force, the initial vibration during unfolding can be reduced, and the wear of the Teflon gasket during the operation of the paddle blade assembly can also be reduced.

[0021] 2. By using an electric hexagon screwdriver with adjustable torque to calibrate the torque range of the half-thread screw, specifically in the range of 0.18 ± 0.02 N·m, it is ensured that when mass-producing and installing the folding paddle assembly, when tightening the upper paddle clamp and the lower paddle clamp with the half-thread screw, the pre-tightening force generated between the Teflon gasket and the folding paddle blade has good consistency, which greatly improves the production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is the overall assembly drawing of the embodiment of the present invention;

[0023] Figure 2 It is the overall explosion drawing of the embodiment of the present invention;

[0024] Figure 3 It is the folding paddle assembly and the forward and reverse rotation motor assembly drawing of the embodiment of the present invention;

[0025] Figure 4 It is the forward and reverse rotation motor assembly and the test base assembly drawing of the embodiment of the present invention;

[0026] Figure 5 It is the schematic diagram of the forward and reverse rotation motor angle range and the pre-tightening force test of the embodiment of the present invention;

[0027] Figure 6 Schematic diagram of the force measuring component according to an embodiment of the present invention.

[0028] Description of the reference numerals: 1, folding paddle assembly; 2, forward and reverse motor assembly; 3, test base assembly; 4, force measuring component; 11, folding paddle blade; 12, Teflon gasket; 13, half-threaded screw; 14, upper paddle clamp; 15, lower paddle clamp; 21, adapter; 22, screw for installing the adapter; 23, forward and reverse motor; 31, base; 32, bracket; 33, storage housing; 41, pressure sensor; 42, pressure gauge display. Detailed implementation manners

[0029] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. 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 protection scope of the present invention.

[0030] This embodiment provides a device for testing and calibrating the pre-tightening force of a folding paddle assembly. Refer to Figure 1-6 , including: a folding paddle assembly 1, a forward and reverse motor assembly 2, a test base assembly 3, and a force measuring component 4.

[0031] The folding paddle assembly 1 includes a folding paddle blade 11, a Teflon gasket 12, a half-threaded screw 13, an upper paddle clamp 14, and a lower paddle clamp 15. Among them, there are four Teflon gaskets 12, which are respectively placed between the folding paddle blade 11 and the upper paddle clamp 14, and between the folding paddle blade 11 and the lower paddle clamp 15. The half-threaded screw 13 passes through the hole positions of the upper paddle clamp 14, the hole positions of the Teflon gasket 12, the hole positions of the folding paddle blade 11, and then passes through the hole positions of the lower Teflon gasket 12, and is connected to the threaded hole positions of the lower paddle clamp 15;

[0032] The forward and reverse motor assembly 2 includes an adapter 21, a screw 22 for installing the adapter, and a forward and reverse motor 23. Among them, the adapter 21 is provided with a guide post, which quickly guides and places the folding paddle assembly 1 during the pre-tightening force test;

[0033] The test base assembly 3 includes a base 31, brackets 32, and a storage housing 33. Among them, four brackets 32 are symmetrically distributed horizontally, and two storage racks 33 are symmetrically distributed vertically. The brackets 32 and the storage housing 33 are both installed on the base 31 by screws.

[0034] The force measuring component 4 includes a pressure sensor 41 and a pressure gauge display 42. The pressure sensor 41 is installed on the brackets 32 by screws and is symmetrically distributed four horizontally. The pressure gauge display 42 is placed on the storage housing 33 and is symmetrically distributed two vertically.

[0035] In this embodiment, referring to Figure 3 , the Teflon gasket 12 is used to buffer the frictional damage between the folding blade 11 and the upper blade clip 14 and the lower blade clip 15 when the folding blade 11 rotates.

[0036] In this embodiment, referring to Figure 3 , when the half-threaded screw 13 tightens the upper blade clip 14 and the lower blade clip 15, the tolerance fit between the Teflon gasket 12 and the folding blade 11 needs to be an interference fit, so as to generate a certain pre-tightening force.

[0037] In this embodiment, referring to Figure 5 , the forward and reverse motor 23 is set with a forward and reverse angle range of -45° to 45°, and is set to rotate at a constant speed of 15 rpm in both forward and reverse directions.

[0038] In this embodiment, referring to Figure 2 and 5 , the forward and reverse motor 23 drives the folding blade assembly 1 to rotate through the guide post set by the adapter 21, and then drives the folding blade 11 to rotate around the smooth rod part of the half-threaded screw 13. When the tip of the folding blade 11 touches the pressure sensor 41, the pressure gauge display 42 displays the pre-tightening force generated by the interference fit between the Teflon gasket 12 and the folding blade 11.

[0039] In this embodiment, referring to Figure 2 and 5 , an electric hexagon screwdriver with adjustable torque is used to adjust the tightening degree of the half-threaded screw 13, and the folding blade assembly is driven to rotate forward and backward by the forward and reverse motor, so that the pressure gauge display shows that the pre-tightening force range of the Teflon gasket and the folding blade in the test is 40 - 60 g, and the difference in pre-tightening force between the two blades needs to be less than 10 g, so that the pre-tightening force generated by the interference fit between the Teflon gasket 12 and the folding blade 11 is appropriate. Thus, when the folding blade assembly 1 works, the folding blade 11 can be normally unfolded by the action of centrifugal force, and the initial vibration during unfolding can be reduced, and the wear of the Teflon gasket 12 during the operation of the blade assembly 1 can also be reduced.

[0040] In this embodiment, referring to Figure 2 and 5 , after using an electric hexagon screwdriver with adjustable torque to adjust the tightening degree of the half-threaded screw 13, the torque of the electric hexagon screwdriver is calibrated, and the calibrated torque range is 0.18 ± 0.02 N·m, so as to ensure that when the folding blade assembly 1 is mass-produced and installed, and the half-threaded screw 13 tightens the upper blade clip 14 and the lower blade clip 15, the pre-tightening force generated between the Teflon gasket 12 and the folding blade 11 is basically the same.

[0041] In this embodiment, referring to Figure 2 and 5, the threaded part of the half-threaded screw needs to be applied with high-strength thread glue to prevent the half-threaded screw from falling off due to the vibration generated during the operation of the folding propeller assembly. An electric hexagon screwdriver with a calibrated torque range of 0.18 ± 0.02 N·m is used to tighten the half-threaded screw 13 applied with high-strength thread glue together with the upper propeller clamp 14, the Teflon gasket 12, the folding propeller blade 11 and the lower propeller clamp 15.

[0042] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A folding paddle assembly preload test and calibration device, characterized in that: The invention comprises a folding paddle assembly (1), a forward and reverse motor assembly (2), a test base assembly (3) and a force measuring assembly (4); the folding paddle assembly (1) is connected to the forward and reverse motor assembly (2), and the folding paddle assembly (1) and the forward and reverse motor assembly (2) are mounted on the test base assembly (3); the force measuring assembly (4) is connected to the forward and reverse motor assembly (2); the forward and reverse motor assembly (2) drives the folding paddle assembly (1) to rotate, and then the dynamic test and calibration of the preload force are realized through the force measuring assembly (4).

2. A folding paddle assembly preload testing and calibration device according to claim 1, characterized in that: The folding paddle assembly (1) comprises a folding paddle (11), a Teflon gasket (12), a half-thread screw (13), an upper paddle clamp (14) and a lower paddle clamp (15), wherein the Teflon gasket (12) has four pieces in total, and the Teflon gasket (12) is respectively placed between the folding paddle (11) and the upper paddle clamp (14) and between the folding paddle (11) and the lower paddle clamp (15), and the half-thread screw (13) passes through the hole of the upper paddle clamp (14), the hole of the Teflon gasket (12) and the hole of the folding paddle (11). The folding blade (11) is provided with a screw threaded hole, and then passes through the hole of the Teflon gasket (12) below and is connected with the threaded hole of the lower paddle clamp (15); the Teflon gasket (12) is used to buffer the friction damage between the folding blade (11) and the upper paddle clamp (14) and the lower paddle clamp (15) when the folding blade (11) rotates; when the half-thread screw (13) is tightened on the upper paddle clamp (14) and the lower paddle clamp (15), the tolerance of the Teflon gasket (12) and the folding blade (11) needs to be a transition fit, thereby generating a certain pre-tightening force.

3. A folding paddle assembly preload testing and calibration device according to claim 1, characterized in that: The forward and reverse motor assembly (2) comprises an adapter (21), an adapter screw (22) and a forward and reverse motor (23), wherein the adapter (21) is provided with a guide column, and during a preload test, the folding paddle assembly (1) is quickly guided and placed, the output shaft of the forward and reverse motor (23) is fixed to the adapter (21) by the adapter screw (22), and the adapter (21) is connected to the folding paddle assembly (1); the forward and reverse motor (23) is set to have a forward and reverse angle range of -45° to 45°, and a rotation speed of 15 rpm for uniform forward and reverse rotation.

4. A folding paddle assembly preload testing and calibration device according to claim 3, characterized in that: The forward and reverse motor (23) drives the folding propeller assembly (1) to rotate via the guide column provided on the adapter (21), thereby driving the folding propeller blade (11) to rotate around the bare rod portion of the half-thread screw (13). When the tip of the folding propeller blade (11) touches the pressure sensor (41), the pressure gauge display (42) displays the preload force generated by the transition fit between the Teflon gasket (12) and the folding propeller blade (11).

5. A folding paddle assembly preload testing and calibration device according to claim 1, characterized in that: The test base assembly (3) comprises a base (31), a bracket (32) and a storage shell (33), wherein four brackets (32) are symmetrically distributed in the transverse direction, and two storage racks (33) are symmetrically distributed in the longitudinal direction, and the brackets (32) and the storage shell (33) are both mounted on the base (31) by screws.

6. A folding paddle assembly preload testing and calibration device according to claim 1, characterized in that: The force measuring assembly (4) comprises a pressure sensor (41) and a pressure gauge display (42). The pressure sensors (41) are mounted on the bracket (32) by screws, and four of them are symmetrically distributed in the transverse direction. The pressure gauge display (42) is placed on the storage shell (33), and two of them are symmetrically distributed in the longitudinal direction. The pressure sensor (41) and the pressure gauge display (42) are connected to provide real-time feedback of preload force data.

7. A folding paddle assembly preload testing and calibration device according to claim 4, characterized in that: An electric hexagon screwdriver with adjustable torque is used to adjust the tightening degree of the half-thread screw (13), and the folding paddle assembly (1) is driven to rotate forward and reversely by a forward and reverse motor, so that the pressure gauge display (42) shows that the test display preload force of the Teflon gasket (12) and the folding paddle (11) is in the range of 40 to 60 g, and the difference in preload force of the two paddles is required to be less than 10 g, so that the preload force generated by the transitional fit of the Teflon gasket (12) and the folding paddle (11) is moderate, so that when the folding paddle assembly (1) is working, the folding paddle (11) is normally unfolded by the action of centrifugal force, and the initial vibration during the unfolding can be reduced, and the wear of the Teflon gasket (12) can be reduced when the paddle assembly (1) is working.

8. A folding paddle assembly preload testing and calibration device according to claim 5, characterized in that: After adjusting the tightening degree of the half-thread screw (13) by using an electric hexagon socket screwdriver with adjustable torque, the torque of the electric hexagon socket screwdriver is calibrated, and the torque range after calibration is 0.18±0.02N·m, thereby ensuring that the folding propeller assembly (1) is installed in batch production, and when the half-thread screw (13) is tightened on the upper propeller clamp (14) and the lower propeller clamp (15), the pre-tightening force generated by the Teflon gasket (12) and the folding propeller blade (11) is basically the same.

9. A folding paddle assembly preload testing and calibration device according to claim 6, characterized in that: The threaded portion of the half-thread screw (13) needs to be coated with high-strength thread glue to prevent the half-thread screw (13) from falling off due to vibration generated when the folding propeller assembly (1) is in operation, and an electric hexagonal screwdriver with a calibrated torque range of 0.18±0.02N·m is used to tighten the half-thread screw (13) coated with high-strength thread glue together with the upper propeller clamp (14), the Teflon gasket (12), the folding propeller blade (11) and the lower propeller clamp (15).

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