WO2022036732A1

WO2022036732A1 - Telescopic device and unmanned aerial vehicle applying telescopic device

Info

Publication number: WO2022036732A1
Application number: PCT/CN2020/111107
Authority: WO
Inventors: 李鹏; 杨陶; 刘云辉
Original assignee: 哈尔滨工业大学（深圳）
Priority date: 2020-08-17
Filing date: 2020-08-25
Publication date: 2022-02-24
Also published as: CN111874207A

Abstract

A telescopic device (10) and an unmanned aerial vehicle (100) applying the telescopic device. The telescopic device comprises a driving mechanism (1), a linkage mechanism (2) and a plurality of telescopic arms (3); the plurality of telescopic arms are respectively hinged to one end of the linkage mechanism, the driving mechanism is hinged to the end of the linkage mechanism away from the telescopic arms, and the driving mechanism drives the linkage mechanism to rotate, so that the linkage mechanism drives the plurality of telescopic arms to extend or retract synchronously. As the linkage mechanism has a linkage property, the driving mechanism drives the linkage mechanism to rotate, so that the linkage mechanism can drive the plurality of telescopic arms to extend or retract synchronously, thereby improving the linkage property of the telescopic device. As one linkage mechanism can simultaneously drive the plurality of telescopic arms to extend or retract synchronously, only one driving mechanism needs to be used for driving the linkage mechanism to rotate, thereby reducing the number of driving mechanisms and reducing the cost of the telescopic device.

Description

Telescopic device and UAV using the telescopic device

technical field

The invention relates to the technical field of industrial machinery, in particular to a telescopic device and an unmanned aerial vehicle using the telescopic device.

Background technique

In the prior art, a scissor-type telescopic device includes a telescopic mechanism and a driving mechanism, and the driving mechanism is used to drive the telescopic mechanism to expand and contract. The scissor-type telescopic device is widely used in the support or connection occasions where the load position is changed. Because of the flexible expansion and contraction ability and the huge difference between the extreme values of the occupied space, the scissor-type telescopic device is favored by users. However, in the case of higher linkage, the existing scissor-type telescopic device cannot meet the requirements of users.

SUMMARY OF THE INVENTION

The main purpose of the present invention is to provide a telescopic device and an unmanned aerial vehicle using the same, aiming to solve the technical problem of poor linkage of scissor-type telescopic devices in the prior art.

In order to solve the above-mentioned technical problems, the technical scheme provided by the present invention is:

A telescopic device, comprising a drive mechanism, a linkage mechanism and a plurality of telescopic arms, the plurality of telescopic arms are respectively hinged with one end of the linkage mechanism, and the drive mechanism is hinged with an end of the linkage mechanism away from the telescopic arms , the drive mechanism drives the linkage mechanism to rotate, so that the linkage mechanism drives a plurality of the telescopic arms to synchronously expand and contract.

Optionally, the telescopic arm includes a plurality of scissor-type units, one end of two adjacent scissor-type units is hinged with each other, and one of the scissor-type units in the telescopic arm is connected to the linkage mechanism. One end is hinged to each other, and the linkage mechanism synchronously drives the two adjacent scissor-type units to rotate with each other, so that the telescopic arm can be extended and retracted.

Optionally, the scissor-type unit includes a plurality of straight rods, the middle parts of the plurality of straight rods of each of the scissor-type units are hinged with each other, and the plurality of the straight rods of the two adjacent scissor-type units are hinged to each other. One ends of the rods are hinged to each other.

Optionally, the telescopic arm further includes a semi-scissor-type unit, the linkage mechanism is hinged with one end of the scissor-type unit, and the semi-scissor-type unit and the scissor-type unit are far from the linkage One end of the mechanism is hinged to each other.

Optionally, the semi-scissor-type unit includes a plurality of semi-straight rods, one end of the plurality of semi-straight rods of each semi-scissor-type unit is hinged with each other, and the other end is hinged with the scissor-type unit. .

Optionally, the linkage mechanism includes a plurality of linkage units, and one ends of two adjacent linkage units are hinged to each other to form a linked chain together.

Optionally, each linkage unit includes a plurality of obtuse-angle links and a plurality of acute-angle links, a plurality of the obtuse-angle links and a plurality of the acute-angle links are hinged to each other, and a plurality of the adjacent two linkage units The obtuse-angle link and a plurality of acute-angle links are hinged with each other to form a linked chain; a plurality of the telescopic arms are respectively hinged with a plurality of the obtuse-angle links, and the drive mechanism is respectively connected with a plurality of acute-angle links The drive mechanism drives a plurality of the acute-angle links to rotate, the acute-angle links drive the obtuse-angle links to rotate, and the obtuse-angle links drive the telescopic arms to synchronously expand and contract.

Optionally, the obtuse-angle link includes a first straight rod and a second straight rod connected to the first straight rod, the angle formed by the first straight rod and the second straight rod is an obtuse angle θ, and the The first straight rod is provided with a first hinge hole and a second hinge hole, the connection between the first straight rod and the second straight rod is provided with a third hinge hole, and the second straight rod is provided with a first hinge hole. Four hinge holes, wherein the distance between any two adjacent ones of the second hinge hole, the third hinge hole and the fourth hinge hole is 1, and a rotation axis passes between the plurality of obtuse-angle links The hinge is realized through the respective second hinge holes;

The acute angle connecting rod includes a third straight rod, a fourth straight rod, a fifth straight rod and a sixth straight rod that are connected end to end, and the angle formed by the third straight rod and the fourth straight rod is an acute angle φ, so The angle formed by the fifth straight rod and the sixth straight rod is an acute angle β, the connection between the third straight rod and the fourth straight rod is provided with a fifth hinge hole, and the third straight rod and the The connection of the sixth straight rod is provided with a sixth hinge hole, the connection of the fourth straight rod and the fifth straight rod is provided with a seventh hinge hole, and the fifth straight rod and the sixth straight rod are provided with a seventh hinge hole. An eighth hinge hole is provided at the connection of the rod, wherein the distance from the fifth hinge hole to the sixth hinge hole is equal to the distance from the fifth hinge hole to the seventh hinge hole and the distance from the fifth hinge hole to the sixth hinge hole is equal to the distance from the fifth hinge hole to the seventh hinge hole. The distance between the hinge holes is 1, the distance from the eighth hinge hole to the sixth hinge hole is equal to the distance from the eighth hinge hole to the seventh hinge hole, and the distance from the eighth hinge hole to the sixth hinge hole is equal to the distance from the eighth hinge hole to the seventh hinge hole. The distance of the hinge hole is m; the m satisfies the formula 1, and the β satisfies the formula 2:

β=2α=(θ-φ)=2π/n (two);

where n is the number of telescopic arms and π is 180 degrees.

Optionally, the telescopic device further includes a connecting assembly, a plurality of the telescopic arms are respectively hinged with one end of the linkage mechanism, the connecting assembly is hinged with an end of the linkage mechanism away from the telescopic arm, the drive The mechanism is connected with the connecting assembly; the driving mechanism drives the connecting assembly to rotate, the connecting assembly drives the linkage mechanism to rotate, and the linkage mechanism drives a plurality of the telescopic arms to extend and retract synchronously.

Optionally, the linkage mechanism is at least two layers, the connection assembly includes a first connector and a second connector, the first connector is hinged with the linkage mechanism on one layer, and the second connector It is hinged with another layer of the linkage mechanism, the driving mechanism is drivingly connected with the first connecting piece, the second connecting piece is fixedly connected with the driving mechanism; the driving mechanism drives the first connecting piece to rotate , the first connecting piece drives the linkage mechanism to rotate, and the linkage mechanism drives the second connecting piece to rotate.

Another technical scheme provided by the present invention is:

An unmanned aerial vehicle is characterized in that it includes a rotor mechanism and a telescopic device, the rotor mechanism is arranged on the end of the telescopic arm away from the drive mechanism, and the rotor mechanism is used to generate flight power.

Optionally, the rotor mechanism includes a motor and a propeller connected to the motor, the motor is disposed on the telescopic arm, and the motor is used to drive the propeller to rotate.

Optionally, the rotor mechanism further includes a rotor base, the rotor base is arranged on the telescopic arm, and the motor is arranged on the rotor base.

Optionally, the rotor base is provided with a first cavity and a second cavity, the rotor mechanism further includes a propeller shaft, the motor is arranged in the first cavity, and the propeller shaft is arranged In the second cavity, the motor is drivingly connected with one end of the propeller shaft, and the propeller is fixedly connected with the end of the propeller shaft away from the motor, wherein the propeller is located at the end of the rotor base. Above, the motor drives the propeller shaft to rotate, and the propeller shaft drives the propeller to rotate.

Optionally, the rotor mechanism further includes a limiter, and the limiter is used to limit the rotation of the rotor base relative to the telescopic arm.

Optionally, a limit slot is provided on the limit member, and the telescopic device further includes a hinge shaft, the hinge shaft is arranged on the telescopic arm and located in the limit slot to limit the rotor. The base rotates relative to the telescopic arm.

Optionally, the rotor mechanism further includes a support rod for supporting the rotor base.

Optionally, the unmanned aerial vehicle further includes a support mechanism, the support mechanism includes a rack bottom plate and a rack cover plate covered on the rack bottom plate, and the linkage mechanism is located between the rack bottom plate and the rack bottom plate. between the rack covers.

Optionally, a limiting portion is provided on the frame cover, and the limiting portion is used to limit the movement of the center position of the linkage mechanism relative to the frame cover.

Optionally, the limiting portion is provided with at least three limiting grooves, the telescopic device further includes at least three hinge shafts, and the hinge shafts are arranged on the linkage mechanism and located in the corresponding limiter. The center position of the linkage mechanism is restricted from moving relative to the frame cover, wherein the hinge shaft can slide along the corresponding limit slot.

Compared with the prior art, the present invention has the following beneficial effects:

Since the linkage mechanism has linkage, the linkage mechanism can be driven to rotate by the drive mechanism, so that the linkage mechanism can drive a plurality of telescopic arms to expand and contract synchronously, thereby improving the linkage of the telescopic device. Since one linkage mechanism can simultaneously drive multiple telescopic arms to synchronously expand and contract, only one driving mechanism is needed to drive the linkage mechanism to rotate, thereby reducing the number of driving mechanisms and reducing the cost of the telescopic device.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can also be obtained according to the structures shown in these drawings without creative efforts.

1 is a schematic diagram of a telescopic device according to an embodiment of the present application;

2 is a schematic diagram of a telescopic boom according to an embodiment of the present application;

3 is a schematic diagram of a scissor unit according to an embodiment of the present application;

FIG. 4 is a schematic diagram of a semi-scissor unit according to an embodiment of the present application;

5 is a schematic diagram of a linkage mechanism according to an embodiment of the present application;

6 is a schematic diagram of a linkage unit according to an embodiment of the present application;

7 is a schematic diagram of a combination of a telescopic arm and a linkage mechanism according to an embodiment of the present application;

8 is a schematic diagram of an obtuse-angle connecting rod according to an embodiment of the present application;

9 is a schematic diagram of an acute-angle connecting rod according to an embodiment of the present application;

10 is a schematic diagram of a combination of different angles of an obtuse-angle connecting rod and an acute-angle connecting rod according to an embodiment of the present application;

11 is a schematic diagram of an acute-angle connecting rod according to another embodiment of the present application;

12 is a schematic diagram of a connection assembly of an embodiment of the present application;

FIG. 13 is a schematic diagram of a first connector according to an embodiment of the present application;

14 is a schematic diagram of a combination of a first connector and an acute-angle connecting rod according to an embodiment of the present application;

FIG. 15 is a schematic diagram of a second connector according to an embodiment of the present application;

16 is a schematic diagram of the combination of the second connecting member and the acute-angle connecting rod according to an embodiment of the present application;

17 is a schematic diagram of a drone according to an embodiment of the present application;

18 is a cross-sectional view of a rotor mechanism according to an embodiment of the present application;

19 is a perspective view of a rotor mechanism according to an embodiment of the present application;

20 is a schematic diagram of a support mechanism of an embodiment of the present application;

FIG. 21 is a schematic diagram of a combination of a support mechanism and a telescopic device according to an embodiment of the present application;

FIG. 22 is a schematic diagram of the maximum deployed state of the drone according to an embodiment of the present application;

23 is a schematic diagram of a semi-deployed state of the drone according to an embodiment of the present application;

FIG. 24 is a schematic diagram of the minimum retracted state of the drone according to an embodiment of the present application;

10. Telescopic device; 1. Drive mechanism; 2. Linkage mechanism; 21. Linkage unit; 211, Obtuse link; 2111, First straight rod; 2112, Second straight rod; 2113, First hinge hole; 2114, No. Second hinge hole; 2115, third hinge hole; 2116, fourth hinge hole; 212, acute angle link; 2121, third straight rod; 2122, fourth straight rod; 2123, fifth straight rod; 2124, sixth straight rod Rod; 2125, the fifth hinge hole; 2126, the sixth hinge hole; 2127, the seventh hinge hole; 2128, the eighth hinge hole; 213, the upper obtuse link; 214, the middle obtuse link; 215, the lower obtuse link ; 216, upper acute angle link; 217, middle acute angle link; 218, lower acute angle link; 219, upper obtuse link; 220, middle acute link; 221, lower obtuse link; 3, telescopic arm; 31, Scissor unit; 311, upper straight rod; 312, middle straight rod; 313, lower straight rod; 314, upper straight rod; 315, middle straight rod; 316, lower straight rod; 32, semi-scissor unit; 321 , upper semi-straight rod; 322, middle semi-straight rod; 323, lower semi-straight rod; 4, connecting assembly; 41, first connecting piece; 411, first connecting rod; 412, second connecting rod; 413, ninth 414, the tenth hinge hole; 415, the eleventh hinge hole; 416, the twelfth hinge hole; 42, the second connecting piece; 421, the third connecting rod; 422, the fourth connecting rod; 423, the first Five connecting rods; 424, the sixth connecting rod; 425, the thirteenth hinge hole; 426, the fourteenth hinge hole; 427, the fifteenth hinge hole; 428, the sixteenth hinge hole; 43, the third connecting piece; 100, unmanned aerial vehicle; 50, rotor mechanism; 51, propeller; 511, propeller hub; 512, blade; 52, motor; 521, first gear; 53, rotor base; 531, first cavity; 532, second cavity; 54, propeller shaft; 541, second gear; 55, first bearing; 56, second bearing; 57, propeller adapter; 58, limit piece; 581, limit slot; 582, hinge shaft; 59, support rod; 60, support mechanism; 61, frame bottom plate; 62, frame cover plate; 621, limit part; 6211, limit slot; 6212, hinge shaft; 70, flight control; 80, inertial measurement unit ; 90, lithium battery; 110, sensor.

detailed description

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, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relationship between various components under a certain posture (as shown in the accompanying drawings). The relative positional relationship, the movement situation, etc., if the specific posture changes, the directional indication also changes accordingly.

In addition, the descriptions involving "first", "second", etc. in the present invention are only for descriptive purposes, and should not be understood as indicating or implying their relative importance or implying the number of indicated technical features. Thus, a feature delimited with "first", "second" may expressly or implicitly include at least one of that feature. In addition, "and/or" in the full text includes three solutions, taking A and/or B as an example, including the technical solution of A, the technical solution of B, and the technical solution that A and B satisfy at the same time; in addition, between the various embodiments The technical solutions can be combined with each other, but must be based on the realization of those of ordinary skill in the art. When the combination of technical solutions is contradictory or cannot be realized, it should be considered that the combination of technical solutions does not exist, nor is it required by the present invention. within the scope of protection.

As shown in FIG. 1 , this embodiment provides a telescopic device 10 . The telescopic device 10 may have a drive mechanism 1 , a linkage mechanism 2 and a plurality of telescopic arms 3 , and the plurality of telescopic arms 3 are respectively hinged to one end of the linkage mechanism 2 . The drive mechanism 1 is hinged with the end of the linkage mechanism 2 away from the telescopic arm 3 , and the drive mechanism 1 drives the linkage mechanism 2 to rotate, so that the linkage mechanism 2 drives the multiple telescopic arms 3 to expand and contract synchronously.

In this embodiment, since the linkage mechanism 2 has linkage, the linkage mechanism 2 drives the linkage mechanism 2 to rotate, so that the linkage mechanism 2 can drive the telescopic arms 3 to expand and contract synchronously, thereby improving the linkage of the telescopic device 10 . Since one linkage mechanism 2 can simultaneously drive multiple telescopic arms 3 to expand and contract synchronously, only one driving mechanism 1 is needed to drive the linkage mechanism 2 to rotate, thereby reducing the number of driving mechanisms 1 and the cost of the telescopic device 10 .

In this embodiment, the driving mechanism 1 is a steering gear.

In this embodiment, the number of the telescopic arms 3 is four, and the four telescopic arms 3 can improve the reliability of the telescopic device 10 . It can be understood that, in an optional embodiment, the number of the telescopic arms 3 is not limited to four, and can be determined according to actual requirements.

As shown in FIG. 2 , the telescopic arm 3 includes a plurality of scissor-type units 31 , one end of two adjacent scissor-type units 31 are hinged to each other, and one scissor-type unit 31 in the telescopic arm 3 is mutually connected with one end of the linkage mechanism 2 . Hinged, the linkage mechanism 2 synchronously drives the two adjacent scissor units 31 to rotate with each other, so that the telescopic arm 3 is telescopic. Through mutual rotation between two adjacent scissor units 31 , the telescopic ability of the telescopic arm 3 is improved.

As shown in FIG. 3 , the scissor-type unit 31 includes a plurality of straight rods (311, 312, 313), and the middle parts of the plurality of straight rods (311, 312, 313) of each scissor-type unit 31 are hinged to each other and are adjacent to each other. One ends of the plurality of straight rods ( 311 , 312 , 313 ) of the two scissor-type units 31 are hinged to each other.

In this embodiment, each scissor-type unit 31 includes three straight rods (311, 312, 313), and the three straight rods (311, 312, 313) are hinged from top to bottom in sequence, and the three straight rods (311, 312, 313) 311, 312, 313) can improve the stability of the scissor unit 31 during the expansion and contraction. It can be understood that, in an optional embodiment, the number of straight bars of each scissor-type unit 31 is not limited to three, and may be determined according to actual requirements.

The scissor unit 31 includes an upper straight rod 311 , a middle straight rod 312 and a lower straight rod 313 . The upper straight rod 311 , the middle straight rod 312 and the lower straight rod 313 are hinged to each other through the hinge shaft.

As shown in FIG. 2 , the telescopic arm 3 further includes a semi-scissor-type unit 32 , the linkage mechanism 2 is hinged with one end of the scissor-type unit 31 , and the semi-scissor-type unit 32 is hinged with the end of the scissor-type unit 31 away from the linkage mechanism 2 . . Through the mutual rotation between the semi-scissor unit 32 and the scissor unit 31 , the telescopic ability of the telescopic arm 3 is improved.

As shown in FIG. 4 , the semi-scissor-type unit 32 includes a plurality of semi-straight rods (321, 322, 323), and one end of the plurality of semi-straight rods (321, 322, 323) of each semi-scissor-type unit 32 is hinged to each other , and the other end is hinged with the scissor unit 31.

In this embodiment, each semi-scissor-type unit 32 includes three semi-straight rods (321, 322, 323), and the three semi-straight rods (321, 322, 323) are hinged from top to bottom in sequence, through three semi-straight rods (321, 322, 323) The semi-straight rods ( 321 , 322 , 323 ) can improve the stability of the semi-scissor unit 32 during expansion and contraction. It can be understood that, in an optional embodiment, the number of semi-straight rods of each semi-scissor-type unit 32 is not limited to three, and may be determined according to actual requirements.

As shown in FIG. 4 , the semi-scissor unit 32 includes an upper semi-straight rod 321 , a middle semi-straight rod 322 and a lower semi-straight rod 323 , an upper semi-straight rod 321 , a lower semi-straight rod 323 and One end of the lower semi-straight rod 323 is hinged to each other through a hinge shaft.

As shown in FIG. 2, one end of the upper straight rod 311, the middle straight rod 315 and the lower straight rod 313 are hinged to each other through the hinge shaft, and one end of the upper straight rod 314, the middle straight rod 312 and the lower straight rod 316 are hinged to each other through the hinge shaft, Therefore, two adjacent scissor-type units 31 are hinged to each other. The corresponding ends of the upper layer semi-straight rod 321, the middle layer straight rod 312 and the lower layer semi-straight rod 323 are hinged to each other through the hinge shaft, and the corresponding ends of the upper layer straight rod 311, the middle layer semi-straight rod 322 and the lower layer straight rod 313 are hinged to each other through the hinge shaft, thereby The half scissor unit 32 and the scissor unit 31 are hinged.

As shown in FIG. 5 , the linkage mechanism 2 includes a plurality of linkage units 21 , and one end of two adjacent linkage units 21 are hinged to each other to form a linked chain together. A plurality of linkage units 21 together form a linked chain, thereby improving the reliability of the linkage mechanism 2 .

Each linkage unit 21 includes a plurality of obtuse-angle links 211 and a plurality of acute-angle links 212 , the plurality of obtuse-angle links 211 and the plurality of acute-angle links 212 are hinged to each other, and the plurality of obtuse-angle links 211 of two adjacent linkage units 21 It is hinged with a plurality of acute-angle links 212 to form a linked chain; a plurality of telescopic arms 3 are respectively hinged with a plurality of obtuse-angle links 211, and the drive mechanism 1 is respectively connected with a plurality of acute-angle links 212; the drive mechanism 1 The multiple acute-angle links 212 are driven to rotate, the multiple acute-angle links 212 drive the multiple obtuse-angle links 211 to rotate, and the multiple obtuse-angle links 211 drive the multiple telescopic arms 3 to expand and contract synchronously. A plurality of obtuse-angle links 211 and a plurality of acute-angle links 212 are hinged to each other to form a linked chain, thereby improving the reliability of the linkage mechanism 2 .

As shown in FIG. 6 , the upper obtuse-angle connecting rod 213 , the middle-layer obtuse-angle connecting rod 214 and the lower-layer obtuse-angle connecting rod 215 are hinged to each other through a hinge shaft, and the upper-layer obtuse-angle connecting rod 213 , the middle layer acute-angle connecting rod 217 , and the lower obtuse-angle connecting rod 215 are mutually connected through a hinge shaft In hinged connection, the upper acute-angle connecting rod 216 , the middle-layer obtuse-angle connecting rod 214 and the lower acute-angle connecting rod 218 are hinged to each other through a hinge shaft, thereby forming a linkage unit 21 . As shown in FIG. 7 , the upper obtuse link 219 , the middle obtuse link 214 and the lower obtuse link 221 are hinged to each other through the hinge shaft, and the upper acute link 216 , the middle acute link 220 and the lower acute link 218 are mutually connected through the hinge shaft hinged, so that two adjacent linkage units 21 are hinged to each other. The upper obtuse-angle connecting rod 213, the middle-layer straight rod 315 and the lower-layer obtuse-angle connecting rod 215 are hinged to each other through a hinge shaft, and the upper-layer straight rod 314, the middle-layer obtuse-angle connecting rod 214 and the lower layer straight rod 316 are hinged to each other through the hinge shaft, so that a plurality of obtuse-angle connecting rods are hinged to each other. (213, 214, 215) and the second scissor unit 31 are hinged to each other.

As shown in FIG. 8 , the obtuse-angle link 211 includes a first straight rod 2111 and a second straight rod 2112 connected to the first straight rod 2111 . The angle formed by the first straight rod 2111 and the second straight rod 2112 is an obtuse angle θ. The straight rod 2111 is provided with a first hinge hole 2113 and a second hinge hole 2114, the connection between the first straight rod 2111 and the second straight rod 2112 is provided with a third hinge hole 2115, and the second straight rod 2112 is provided with a fourth hinge hole 2115. The hinge hole 2116, wherein the distance between any two adjacent second hinge holes 2114, the third hinge hole 2115 and the fourth hinge hole 2116 is 1, and the plurality of obtuse-angle links 211 pass through the respective The second hinge hole 2114 realizes the hinge.

As shown in FIG. 9 , the acute-angle link 212 includes a third straight rod 2121 , a fourth straight rod 2122 , a fifth straight rod 2123 and a sixth straight rod 2124 that are connected end to end, and the third straight rod 2121 and the fourth straight rod 2122 form The angle formed by the fifth straight rod 2123 and the sixth straight rod 2124 is an acute angle β, the connection of the third straight rod 2121 and the fourth straight rod 2122 is provided with a fifth hinge hole 2125, and the third straight rod 2121 and the sixth straight rod 2124 are connected with a sixth hinge hole 2126, the fourth straight rod 2122 and the fifth straight rod 2123 are connected with a seventh hinge hole 2127, the fifth straight rod 2123 and the sixth straight rod An eighth hinge hole 2128 is provided at the connection of 2124, wherein the distance from the fifth hinge hole 2125 to the sixth hinge hole 2126 is equal to the distance from the fifth hinge hole 2125 to the seventh hinge hole 2127 and the distance from the fifth hinge hole 2125 to the sixth hinge hole 2125 The distance of the hinge hole 2126 is 1, the distance from the eighth hinge hole 2128 to the sixth hinge hole 2126 is equal to the distance from the eighth hinge hole 2128 to the seventh hinge hole 2127, and the distance from the eighth hinge hole 2128 to the sixth hinge hole 2126 is m;

m satisfies formula 1, and β satisfies formula 2:

β=2α=(θ-φ)=2π/n (two);

Among them, n is the number of telescopic arms 3, and π is 180 degrees.

As shown in FIG. 10 , the fifth hinge hole 2125 is B, the sixth hinge hole 2126 is A, the seventh hinge hole 2127 is C, and the eighth hinge hole 2128 is G. When formula 1 is established, take G as the center and m as the radius, draw a circle through A, and we know that the circle must pass through C. Since the central angle corresponding to the chord AC is ∠AGC=β, according to the circular angle theorem, the circular angle of ∠AGC is β/2. When formula 1 and formula 2 are both established, it can be known that α=β/2, and ∠AOC=α is deduced, where α is the circumference angle corresponding to the chord AC, that is to say, the center O is on the circle, and regardless of the obtuse angle link How to rotate 211 and acute angle link 212, the above conclusion is always established. Under the condition that Formula 1 and Formula 2 are established at the same time, when the driving mechanism 1 drives the linkage mechanism 2 to rotate, the linkage mechanism 2 can drive the multiple telescopic arms 3 to always expand and contract in a preset direction, thereby improving the controllability of the telescopic device 10 . As shown in FIG. 7 , the preset direction is a linear direction formed by the mutually hinged positions of the middle portions of the plurality of straight rods of each scissor-type unit 31 .

As shown in FIG. 11 , in this embodiment, the upper acute-angle connecting rod may also include a third straight rod 2121 and a fourth straight rod 2122 , and a third straight rod 2121 and a fourth straight rod 2122 are provided at the connection of the third straight rod 2121 and the fourth straight rod 2122 Five hinge holes 2125 , the end of the third straight rod 2121 away from the fifth hinge hole 2125 is provided with a sixth hinge hole 2126 , and the end of the fourth straight rod 2122 away from the fifth hinge hole 2125 is provided with a seventh hinge hole 2127 . By not including the upper acute angle link 216 of the fifth straight rod 2123 and the sixth straight rod 2124 , the interference between the upper acute angle link and other components can be avoided, thereby ensuring the normal operation of the linkage mechanism 2 . It can be understood that, in an optional embodiment, the upper acute-angle connecting rod may also include a fifth straight rod 2123 and a sixth straight rod 2124, and it is only necessary to ensure that the upper acute-angle connecting rod does not interfere with other components during the rotation process. Can.

As shown in FIG. 12 , the telescopic device 10 further includes a connecting assembly 4, a plurality of telescopic arms 3 are respectively hinged with one end of the linkage mechanism 2, the connecting assembly 4 is hinged with one end of the linkage mechanism 2 away from the telescopic arm 3, the driving mechanism 1 and the connecting assembly 4 connection; the driving mechanism 1 drives the connecting assembly 4 to rotate, the connecting assembly 4 drives the linkage mechanism 2 to rotate, and the linkage mechanism 2 drives the multiple telescopic arms 3 to synchronously expand and contract. When the connecting assembly 4 is damaged, only the more damaged connecting assembly 4 is needed, and the entire driving mechanism 1 does not need to be replaced, thereby reducing the replacement cost of the telescopic device 10 .

The linkage mechanism 2 has at least two layers. The connecting assembly 4 includes a first connecting member 41 and a second connecting member 42. The first connecting member 41 is hinged with one layer of the linkage mechanism 2, and the second connecting member 42 is connected with the other layer of the linkage mechanism 2. Hinged, the driving mechanism 1 is drivingly connected with the first connecting member 41, and the second connecting member 42 is fixedly connected with the driving mechanism 1; the driving mechanism 1 drives the first connecting member 41 to rotate, the first connecting member 41 drives the linkage mechanism 2 to rotate, and the linkage mechanism 2 to drive the second connecting piece 42 to rotate. The first connecting member 41 is drivingly connected with the driving mechanism 1 , and the second connecting member 42 is fixedly connected with the driving mechanism 1 , so that the driving mechanism 1 can reliably drive the linkage mechanism 2 to rotate, thereby improving the reliability of the telescopic device 10 . In this embodiment, the linkage mechanism 2 has three layers. It can be understood that, in an optional embodiment, the linkage mechanism 2 is not limited to three layers, and may be determined according to actual needs.

As shown in FIGS. 13 and 14 , the first connecting member 41 is provided with a ninth hinge hole 413 , a tenth hinge hole 414 , an eleventh hinge hole 415 and a twelfth hinge hole 416 . The ten hinge holes 414 , the eleventh hinge holes 415 and the twelfth hinge holes 416 are respectively connected with the eighth hinge holes 2128 corresponding to the acute-angle link of the middle layer to realize hinge connection. In this embodiment, since the distance from the center O to the eighth hinge hole 2128 is always m, the distance from the ninth hinge hole 413 to the center O is equal to the distance from the tenth hinge hole 414 to the center O is equal to the distance from the eleventh hinge hole 415 The distance from the center O is equal to the distance from the twelfth hinge hole 416 to the center O and the distance from the ninth hinge hole 413 to the center O is equal to m, so that the hinge holes on the first connecting piece 41 correspond to the middle linkage mechanism 2 respectively The eighth hinge hole 2128 realizes hinge.

In this embodiment, the first connecting member 41 includes a first connecting rod 411 and a second connecting rod 412 vertically connected to the first connecting rod 411 , wherein the connection between the first connecting rod 411 and the second connecting rod 412 is set as In the center O, both ends of the first connecting rod 411 are provided with a ninth hinge hole 413 and a tenth hinge hole 414 , and both ends of the second connecting rod 412 are provided with an eleventh hinge hole 415 and a twelfth hinge hole 416 .

As shown in FIGS. 15 and 16 , the second connecting member 42 is provided with a thirteenth hinge hole 425 , a fourteenth hinge hole 426 , a fifteenth hinge hole 427 and a sixteenth hinge hole 428 . The thirteenth hinge hole 425 , the fourteenth hinge hole 426 , the fifteenth hinge hole 427 , and the sixteenth hinge hole 428 are respectively connected with the eighth hinge hole 2128 corresponding to the lower acute-angle connecting rod. In this embodiment, since the distance from the center O to the eighth hinge hole 2128 is always m, the distance from the thirteenth hinge hole 425 to the center O is equal to the distance from the fourteenth hinge hole 426 to the center O is equal to the fifteenth hinge hole The distance from the center O is equal to the distance from the sixteenth hinge hole 428 to the center O and the distance from the thirteenth hinge hole 425 to the center O is m, so that the hinge holes on the second connecting piece 42 are respectively corresponding to the lower chain links. The eighth hinge hole 2128 realizes hinge.

In this embodiment, the second connecting member 42 includes a third connecting rod 421 , a fourth connecting rod 422 , a fifth connecting rod 423 and a sixth connecting rod 424 connected end to end, wherein the third connecting rod 421 and the fifth connecting rod 423 are arranged in parallel, the fourth connecting rod 422 and the sixth connecting rod 424 are arranged in parallel, the fourth connecting rod 422 is provided with a thirteenth hinge hole 425 and a fourteenth hinge hole 426, and the sixth connecting rod 424 is provided with a tenth The center point of the fifth hinge hole 427 and the sixteenth hinge hole 428, the center point of the thirteenth hinge hole 425, the fourteenth hinge hole 426, the fifteenth hinge hole 427 and the sixteenth hinge hole 428 is set as the center O.

As shown in FIG. 1 , the connecting assembly 4 further includes a third connecting piece, the output shaft of the driving mechanism 1 is fixedly connected with the third connecting piece, and the third connecting piece is fixedly connected with the first connecting piece 41 . The driving mechanism 1 drives the third connecting piece to rotate, the third connecting piece drives the first connecting piece 41 to rotate, the first connecting piece 41 drives the linkage mechanism 2 to rotate, and the linkage mechanism 2 drives the telescopic arm 3 to expand and contract, and simultaneously drives the second connecting piece 42 Rotating, the second connecting member 42 rotates to drive the driving mechanism 1 to rotate. In this embodiment, the third connecting member is a swing arm.

At present, most of the research on multi-rotor UAVs is focused on the rack platform with a fixed wheelbase, combined with perception technology and optimized control algorithms to enhance the ability to adapt to the environment. When the large multi-rotor UAV is disturbed by unstable airflow during flight, due to its large rotational inertia, the large multi-rotor UAV can still maintain good stability; but when the small multi-rotor UAV is flying When disturbed by unstable airflow during the process, due to its small moment of inertia, it is easily disturbed by airflow and becomes very unstable, resulting in limited use of small multi-rotor UAVs. When a small multi-rotor UAV encounters a narrow passage during flight, the small multi-rotor UAV can easily pass through the passage due to its small wheelbase; The inability to traverse the aisle easily has limited the use of large multi-rotor drones.

As shown in FIG. 17 , this embodiment provides an unmanned aerial vehicle 100. The unmanned aerial vehicle 100 may have a rotor mechanism 50 and the telescopic device 10 in any of the above embodiments. The rotor mechanism 50 is arranged on the telescopic arm 3 away from the drive mechanism. At one end of 1, a rotor mechanism 50 is used to generate flight power.

In this embodiment, the linkage mechanism 2 is driven by the drive mechanism 1 to rotate, and the linkage mechanism 2 drives the multiple telescopic arms 3 to expand and contract synchronously, so that the UAV 100 can change the wheelbase of the rotor mechanism 50 to make its own in different scenarios. The volume of the UAV 100 changes, so that the UAV 100 can fly in different scenarios, thereby improving the applicability of the UAV 100 .

As shown in FIG. 18 , the rotor mechanism 50 includes a propeller 51 and a motor 52 , the motor 52 is arranged on the telescopic arm 3 , and the motor 52 is used to drive the propeller 51 to rotate.

The propeller 51 includes a propeller hub 511 and a plurality of propeller blades 512. The plurality of propeller blades 512 are evenly arranged along the circumferential direction of the propeller hub. The motor 52 is fixedly connected to the propeller hub 511. The motor 52 drives the propeller hub 511 to rotate, and the propeller hub 511 drives the propeller blades. 512 turns.

The rotor mechanism 50 further includes a rotor base 53 , the motor 52 is arranged on the rotor base 53 , and the rotor base 53 is arranged on the telescopic arm 3 .

The rotor base 53 is provided with a first cavity 531 and a second cavity 532, the rotor mechanism 50 further includes a propeller shaft 54, the motor 52 is arranged in the first cavity 531, and the propeller shaft 54 is arranged in the second cavity In 532, the motor 52 is drivingly connected with one end of the propeller shaft 54, the propeller 51 is fixedly connected with one end of the propeller shaft 54 away from the motor 52, wherein the propeller 51 is located above the rotor base 53, the motor 52 drives the propeller shaft 54 to rotate, and the propeller shaft 54 drives the propeller 51 to rotate.

The rotor mechanism 50 further includes a first bearing 55 , a second bearing 56 and a propeller adapter 57 , the propeller shaft 54 is arranged in the second cavity 532 through the first bearing 55 and the second bearing 56 , and the motor 52 is provided with a first gear 521 , the propeller shaft 54 is provided with a second gear 541 adapted to the first gear 521, the motor 52 is connected with one end of the propeller shaft 54 through the first gear 521 and the second gear 541, and the propeller hub 511 and one end of the propeller shaft 54 pass through The propeller adapter 57 is fixedly connected. The first gear 521 and the second gear 541 are located below the rotor base 53, the propeller hub 511 and the blades 512 are located above the rotor base 53, the motor 52 drives the first gear 521 to rotate, and the first gear 521 drives the second gear 521. The gear 541 rotates, the second gear 541 drives the propeller shaft 54 to rotate, the propeller shaft 54 drives the propeller adapter 57 to rotate, the propeller adapter 57 drives the propeller hub 511 to rotate, and the propeller hub 511 drives the propeller blade 512 to rotate.

As shown in FIG. 19 , the rotor mechanism 50 further includes a limiter 58, which is used to limit the rotation of the rotor base 53 relative to the telescopic arm 3, so as to ensure that the rotor base 53 will not rotate during the flight of the UAV 100. The position relative to the telescopic arm 3 is always kept unchanged, thereby improving the reliability of the UAV 100 during flight. In this embodiment, the limiting member 58 is disposed on the rotor base 53 .

As shown in FIG. 7 , FIG. 19 and FIG. 21 , the limiting member 58 is provided with a limiting groove 581 , and the telescopic device 10 further includes a hinge shaft 582 . The hinge shaft 582 is arranged on the telescopic arm 3 and is located in the limiting groove 581 . In order to limit the rotation of the rotor base 53 relative to the telescopic arm 3 . Through the cooperation between the limiting groove 581 and the hinge shaft 582, the reliability of the limiting member 58 can be improved.

As shown in FIG. 19 , the rotor mechanism 50 further includes a support rod 59 for supporting the rotor base 53 . Supporting the rotor base 53 by the support rod 59 can prevent the UAV 100 from tipping over during the landing process, so that a certain distance is always maintained between the propeller 51 and the ground, thereby ensuring the service life of the rotor mechanism 50 . In this embodiment, the support rod 59 is arranged at the bottom of the rotor base 53 .

As shown in FIG. 20 , the UAV 100 further includes a support mechanism 60 . The support mechanism 60 includes a rack bottom plate 61 and a rack cover plate 62 covered on the rack bottom plate 61 . The linkage mechanism 2 is located between the rack bottom plate 61 and the machine. between the frame cover 62 .

The frame cover 62 is provided with a limit portion 621, and the limit portion 621 is used to limit the movement of the center position of the linkage mechanism 2 (that is, the center O) relative to the frame cover 62, so that the telescopic device 10 is in the process of expanding and contracting. , the central position of the linkage mechanism 2 remains unchanged relative to the frame cover 62 , thereby improving the reliability of the UAV 100 during flight.

As shown in FIG. 7 and FIG. 21 , the limiting portion 621 is provided with at least three limiting slots 6211 , and the telescopic device 10 further includes at least three hinge shafts 6212 . The hinge shafts 6212 are provided on the linkage mechanism 2 and are located in the corresponding In the limiting slot 6211 , the central position of the linkage mechanism 2 is restricted from moving relative to the frame cover 62 , wherein the hinge shaft can slide along the corresponding limiting slot 6211 . Through the cooperation of the three limiting grooves 6211 and the three hinge shafts 6212, the reliability of the limiting portion 621 can be improved. The hinge shaft 6212 can slide along the corresponding limiting groove 6211 , which can prevent the linkage mechanism 2 from interfering with the frame cover 62 during the expansion and contraction process, thereby ensuring the normal operation of the expansion device 10 .

As shown in FIG. 20 , the number of limit slots 581 is four, and the included angle between two adjacent limit slots 581 is 2π/n, where n is the number of telescopic arms 3 . In this embodiment, the number of telescopic arms 3 is 4, and the included angle between two adjacent guide grooves is 90 degrees.

As shown in FIG. 17 , the UAV 100 further includes a flight controller 70 , an inertial measurement unit 80 , a lithium battery 90 and a sensor 110 arranged on the support mechanism 60 . The flight controller 70 is connected to the inertial measurement unit 80 , the lithium battery 90 and the sensor respectively. 110 connections.

In this embodiment, the flight controller 70 is arranged on the frame cover 62 , the inertial measurement unit 80 is arranged on the flight controller 70 , the lithium battery 90 is arranged on the inertial measurement unit 80 , and the sensor 110 is arranged at the bottom of the frame bottom plate 61 . superior.

In this embodiment, the inertial measurement unit 80 is an IMU inertial measurement unit 80 . The sensor 110 is an optical flow sensor 110 .

Figure 22 shows the drone 100 reaching the maximum deployed state; Figure 23 shows the drone 100 reaching the semi-deployed state; Figure 24 shows the drone 100 reaching the minimum retracted state.

The above descriptions are only the preferred embodiments of the present invention, and are not intended to limit the scope of the present invention. Under the inventive concept of the present invention, the equivalent structural transformations made by the contents of the description and drawings of the present invention, or the direct/indirect application Other related technical fields are included in the scope of patent protection of the present invention.

Claims

A telescopic device, characterized in that it includes a driving mechanism, a linkage mechanism and a plurality of telescopic arms, the plurality of telescopic arms are respectively hinged with one end of the linkage mechanism, and the driving mechanism and the linkage mechanism are far away from the telescopic arms One end of the arm is hinged, and the drive mechanism drives the linkage mechanism to rotate, so that the linkage mechanism drives a plurality of the telescopic arms to extend and retract synchronously.
The telescopic device according to claim 1, wherein the telescopic arm comprises a plurality of scissor-type units, one end of two adjacent scissor-type units is hinged to each other, and one of the telescopic arms is The scissor-type unit is hinged with one end of the linkage mechanism, and the linkage mechanism synchronously drives the two adjacent scissor-type units to rotate with each other, so that the telescopic arm can be extended and retracted.
The telescopic device according to claim 2, wherein the scissor-type unit includes a plurality of straight rods, and the middle parts of the plurality of straight rods of each of the scissor-type units are hinged with each other, and two adjacent ones One ends of the plurality of straight rods of the scissor-type unit are hinged with each other.
The telescopic device according to claim 2, wherein the telescopic arm further comprises a semi-scissor-type unit, the linkage mechanism is hinged with one end of the scissor-type unit, and the semi-scissor-type unit is connected to One ends of the scissor-type units away from the linkage mechanism are hinged to each other.
The telescopic device according to claim 4, wherein the semi-scissor-type unit comprises a plurality of semi-straight rods, and one end of the plurality of semi-straight rods of each of the semi-scissor-type units is hinged with each other, and the other side is hinged with each other. One end is mutually hinged with the scissor unit.
The telescopic device according to claim 1, wherein the linkage mechanism comprises a plurality of linkage units, and one end of two adjacent linkage units are hinged to each other to form a linked chain together.
The telescopic device according to claim 6, wherein each linkage unit comprises a plurality of obtuse-angle links and a plurality of acute-angle links, and the plurality of the obtuse-angle links and the plurality of the acute-angle links are hinged with each other, A plurality of obtuse-angle links and a plurality of acute-angle links of two adjacent linkage units are hinged with each other to form a linked chain; a plurality of the telescopic arms are respectively hinged with a plurality of the obtuse-angle links, and the The driving mechanism is respectively connected with a plurality of acute-angle connecting rods; the driving mechanism drives a plurality of the acute-angle connecting rods to rotate, a plurality of the acute-angle connecting rods drive a plurality of the obtuse-angle connecting rods to rotate, and a plurality of the obtuse-angle connecting rods drive a plurality of the obtuse-angle connecting rods to rotate A plurality of the telescopic arms are synchronously telescopic.
The telescopic device according to claim 7, wherein:

The obtuse-angle link includes a first straight rod and a second straight rod connected to the first straight rod, the angle formed by the first straight rod and the second straight rod is an obtuse angle θ, and the first straight rod A first hinge hole and a second hinge hole are provided on the top, a third hinge hole is provided at the connection between the first straight rod and the second straight rod, and a fourth hinge hole is provided on the second straight rod, Wherein, the distance between any two adjacent ones of the second hinge hole, the third hinge hole and the fourth hinge hole is 1, and the plurality of obtuse-angle links pass through the respective The second hinge hole realizes hinge;

The acute angle connecting rod includes a third straight rod, a fourth straight rod, a fifth straight rod and a sixth straight rod that are connected end to end, and the angle formed by the third straight rod and the fourth straight rod is an acute angle φ, so The angle formed by the fifth straight rod and the sixth straight rod is an acute angle β, the connection between the third straight rod and the fourth straight rod is provided with a fifth hinge hole, and the third straight rod and the The connection of the sixth straight rod is provided with a sixth hinge hole, the connection of the fourth straight rod and the fifth straight rod is provided with a seventh hinge hole, and the fifth straight rod and the sixth straight rod are provided with a seventh hinge hole. An eighth hinge hole is provided at the connection of the rod, wherein the distance from the fifth hinge hole to the sixth hinge hole is equal to the distance from the fifth hinge hole to the seventh hinge hole and the distance from the fifth hinge hole to the sixth hinge hole is equal to the distance from the fifth hinge hole to the seventh hinge hole. The distance between the hinge holes is 1, the distance from the eighth hinge hole to the sixth hinge hole is equal to the distance from the eighth hinge hole to the seventh hinge hole, and the distance from the eighth hinge hole to the sixth hinge hole is equal to the distance from the eighth hinge hole to the seventh hinge hole. The distance of the hinge hole is m; the m satisfies the formula 1, and the β satisfies the formula 2:

β=2α=(θ-φ)=2π/n (two);

where n is the number of telescopic arms and π is 180 degrees.
The telescopic device according to claim 1, wherein the telescopic device further comprises a connecting assembly, a plurality of the telescopic arms are respectively hinged with one end of the linkage mechanism, and the connecting assembly and the linkage mechanism are far away from the One end of the telescopic arm is hinged, and the drive mechanism is connected with the connection assembly; the drive mechanism drives the connection assembly to rotate, the connection assembly drives the linkage mechanism to rotate, and the linkage mechanism drives a plurality of the telescopic arms The arms extend and retract synchronously.
The telescopic device according to claim 9, wherein the linkage mechanism is at least two layers, the connecting component comprises a first connecting member and a second connecting member, the first connecting member is connected to the one layer of the The linkage mechanism is hinged, the second connecting piece is hinged with another layer of the linkage mechanism, the driving mechanism is drivingly connected with the first connecting piece, and the second connecting piece is fixedly connected with the driving mechanism; the The driving mechanism drives the first connecting piece to rotate, the first connecting piece drives the linkage mechanism to rotate, and the linkage mechanism drives the second connecting piece to rotate.
An unmanned aerial vehicle, characterized in that it comprises a rotor mechanism and the telescopic device according to any one of claims 1-10, the rotor mechanism is arranged on one end of the telescopic arm away from the drive mechanism, the rotor Mechanisms are used to generate flight power.
The drone according to claim 11, wherein the rotor mechanism comprises a motor and a propeller connected to the motor, the motor is arranged on the telescopic arm, and the motor is used to drive the propeller to rotate .
The drone according to claim 12, wherein the rotor mechanism further comprises a rotor base, the rotor base is arranged on the telescopic arm, and the motor is arranged on the rotor base.
The unmanned aerial vehicle according to claim 13, wherein the rotor base is provided with a first cavity and a second cavity passing through, the rotor mechanism further comprises a propeller shaft, and the motor is arranged on the rotor base. In the first cavity, the propeller shaft is arranged in the second cavity, the motor is in driving connection with one end of the propeller shaft, and the propeller is fixedly connected with the end of the propeller shaft away from the motor, wherein , the propeller is located above the rotor base, the motor drives the propeller shaft to rotate, and the propeller shaft drives the propeller to rotate.
The unmanned aerial vehicle according to claim 13, wherein the rotor mechanism further comprises a limiter, and the limiter is used to limit the rotation of the rotor base relative to the telescopic arm.
The unmanned aerial vehicle according to claim 15, wherein a limit groove is provided on the limit member, and the telescopic device further comprises a hinge shaft, and the hinge shaft is provided on the telescopic arm and located at the into the limiting groove to limit the rotation of the rotor base relative to the telescopic arm.
The drone according to claim 13, wherein the rotor mechanism further comprises a support rod for supporting the rotor base.
The unmanned aerial vehicle according to claim 11, wherein the unmanned aerial vehicle further comprises a support mechanism, the support mechanism comprises a rack bottom plate and a rack cover plate covered on the rack bottom plate, the The linkage mechanism is located between the rack bottom plate and the rack cover.
The unmanned aerial vehicle according to claim 18, wherein the frame cover is provided with a limit portion, and the limit portion is used to limit the occurrence of the central position of the linkage mechanism relative to the frame cover. move.
The unmanned aerial vehicle according to claim 19, wherein at least three limiting grooves are provided on the limiting portion, and the telescopic device further comprises at least three hinge shafts, and the hinge shafts are arranged on the on the linkage mechanism, and is located in the corresponding limit slot, so as to restrict the central position of the linkage mechanism from moving relative to the frame cover, wherein the hinge shaft can slide along the corresponding limit slot .