WO2022122048A1

WO2022122048A1 - Split-type five-degrees-of-freedom parallel mechanism

Info

Publication number: WO2022122048A1
Application number: PCT/CN2021/142598
Authority: WO
Inventors: 吴孟丽; 李明宇; 林玉飞; 李德祚; 王旭浩; 唐杰; 张军
Original assignee: 中国民航大学
Priority date: 2020-12-07
Filing date: 2021-12-29
Publication date: 2022-06-16
Also published as: CN112454336A; CN112454336B

Abstract

A split-type five-degrees-of-freedom parallel mechanism, comprising a fixed platform (1), a moving platform (2), a first branch chain (I), a second branch chain (II), and a third branch chain (III), and having three translational degrees of freedom and two rotational degrees of freedom. The fixed platform (1) comprises a base (101) fixed to the ground, two first guide rails (102), two first hinged supports (103), two first telescopic rods (4), a sub-platform (3), and a third hinged support (301). The fixed platform (1) is of a split structure, and three active pairs are arranged on the sub-platform (3).

Description

A split-type five-degree-of-freedom parallel mechanism

technical field

The invention belongs to the technical field of parallel mechanisms, in particular to a split-type five-degree-of-freedom parallel mechanism.

Background technique

The parallel mechanism has been widely used in various fields in recent years. It has the advantages of high precision, stable operation and high work efficiency, so the parallel mechanism has high application value.

The five-degree-of-freedom parallel mechanism has also been widely used in recent years, because it has one less degree of freedom, so the structure is simpler, and at the same time has good stability, it can complete some processing processes that cannot be completed by the six-degree-of-freedom mechanism; such as China Patent Publication No. CN201821923752.5 discloses a novel five-degree-of-freedom parallel mechanism, which has a very simple mechanism and strong bearing capacity, but has a small working space and is easily interfered with in motion; the split structure can increase the mechanism space and reduce interference, so the use of split-type mechanism on the basis of the five-degree-of-freedom parallel mechanism has a good prospect.

SUMMARY OF THE INVENTION

In order to solve the above problems, the purpose of the present invention is to provide a split-type five-degree-of-freedom parallel mechanism.

In order to achieve the above object, the split-type five-degree-of-freedom parallel mechanism provided by the present invention includes a fixed platform, a moving platform, a first branch, a second branch and a third branch;

The fixed platform includes a base fixed on the ground, two first guide rails, two first hinged supports, two first telescopic rods, a sub-platform and a third hinged support; the two first guide rails are symmetrical The two first hinge supports are fixed on both ends of one side of the fixed platform, and the rotation axis is perpendicular to the upper surface of the base; Both ends are respectively fixed with a fourth hinged support, each fourth hinged support is respectively connected with one end of a first telescopic rod to form a first rotation pair, and the other end of the first telescopic rod is connected with a first hinged support The second rotating pair is connected to form a second rotating pair, and the rotation axes of the first rotating pair and the second rotating pair are parallel to each other; the two first telescopic rods on the fixed platform are active pairs, which can realize the movement of the sub-platform relative to the fixed platform, so that the mechanism is divided into two parts. body structure;

The moving platform includes a platen, a second hinged support and two first spherical hinge supports; the second hinged support and the two first spherical hinged supports are fixed on the bottom surface of the platen in the shape of a zigzag, and the second The rotation axis of the hinged support is parallel to the center line of the two first spherical hinge supports;

The structure of the first branch chain and the second branch chain are completely identical and symmetrical, and both include a first connecting rod, a first sliding block, a first spherical hinge and a second spherical hinge; one end of the first connecting rod passes through the first ball The hinge is connected with a first spherical hinge support fixed on the moving platform, and the other end is connected with the second spherical hinge support fixed on the first slider through the second spherical hinge, and the second spherical hinge support is fixedly connected On the surface of the first sliding block; the first sliding block is mounted on the first guide rail in a way that can move up and down to form a first moving pair;

The third branch is the second connecting rod; one end of the second connecting rod is connected with the second hinged support on the moving platform to form the fourth rotating pair, and the other end is connected with the third hinged support on the fixed platform to form the fourth rotating pair. Three rotation pairs.

The base adopts a rectangular plate-like structure.

The sub-platform adopts a triangular plate-like structure.

The split-type five-degree-of-freedom parallel mechanism provided by the present invention has the following advantages:

1. The fixed platform adopts a split structure, and there are three active pairs on the sub-platform, which ensures the motion characteristics of the moving platform, makes the driving system centralized, reduces the influence of the control system on the moving platform, makes the parallel mechanism modular, and reduces the batch maintenance of the mechanism. difficulty.

2. The mechanism is symmetrical as a whole and adopts multiple ball joints, which increases the flexibility and isotropy of the mechanism and increases the movement performance of the mechanism.

3. The split structure is adopted, which increases the working space of the moving platform.

Description of drawings

FIG. 1 is a schematic structural diagram of a split-type five-degree-of-freedom parallel mechanism provided by the present invention.

FIG. 2 is a schematic structural diagram of a fixed platform in a split-type five-degree-of-freedom parallel mechanism provided by the present invention.

FIG. 3 is a schematic structural diagram of the intermediate moving platform of the split-type five-degree-of-freedom parallel mechanism provided by the present invention.

FIG. 4 is a schematic structural diagram of the first branch chain and the second branch chain in the split-type five-degree-of-freedom parallel mechanism provided by the present invention.

In the figure: 1, fixed platform; 101, base; 102, first guide rail; 103, first hinged support; 2, movable platform; 201, platen; 202, first ball hinge support; 203, second hinge Support; 3. Sub-platform; 301, Third hinged support; 302, Fourth hinged support; 4. First telescopic rod; 5. First rotating pair; 6. Second rotating pair; 7. First connecting Rod; 8, the first ball joint; 9, the second ball joint; 10, the first slider; 1001, the second ball joint support; 11, the first moving pair; 12, the second link; 13, the third Rotating pair; 14. The fourth rotating pair; I, the first branch; II, the second branch; III, the third branch.

Detailed ways

The split-type five-degree-of-freedom parallel mechanism provided by the present invention will be described in detail below with reference to the accompanying drawings.

As shown in Figure 1-Figure 4, the split-type five-degree-of-freedom parallel mechanism provided by the present invention includes a fixed platform 1, a moving platform 2, a first branch I, a second branch II and a third branch III;

The fixed platform 1 includes a base 101 fixed on the ground, two first guide rails 102, two first hinged supports 103, two first telescopic rods 4, a sub-platform 3 and a third hinged support 301; The two first guide rails 102 are fixed on both ends of the upper surface of the fixed platform 1 in a symmetrical manner, and are perpendicular to the fixed platform 1; the two first hinge supports 103 are fixed on both ends of one side of the fixed platform 1, and The rotation axis is perpendicular to the upper surface of the base 101; the two ends of the sub-platform 3 are respectively fixed with a fourth hinged support 302, and each fourth hinged support 302 is respectively connected with one end of a first telescopic rod 4 to form a first Rotating pair 5, the other end of the first telescopic rod 4 is connected with a first hinged support 103 to form a second rotating pair 6, and the rotation axes of the first rotating pair 5 and the second rotating pair 6 are parallel to each other; the fixed platform 1 The upper two first telescopic rods 4 are active pairs, which can realize the movement of the sub-platform 3 relative to the fixed platform 1, so that the mechanism has a split structure;

The moving platform 2 includes a platen 201, a second hinged support 203 and two first spherical hinge supports 202; the second hinged support 203 and the two first spherical hinge supports 202 are fixed on the platen 201 in a shape of a and the rotation axis of the second hinge support 203 is parallel to the center line of the two first spherical hinge supports 202;

The structures of the first branch I and the second branch II are identical and symmetrical, and both include a first connecting rod 7, a first sliding block 10, a first spherical hinge 8 and a second spherical hinge 9; the first connecting rod One end of 7 is connected to a first spherical hinge support 202 fixed on the moving platform 2 through the first spherical hinge 8, and the other end is supported by the second spherical hinge 9 fixed on the first slider 10. The seats 1001 are connected, and the second spherical hinge support 1001 is fixedly connected to the surface of the first sliding block 10;

The third branch III is the second connecting rod 12; The hinge supports 301 are connected to form the third rotating pair 13 .

The base 101 adopts a rectangular plate-like structure.

The sub-platform 3 adopts a triangular plate-like structure.

Now, the axis direction of the first guide rail 102 fixed on the base 101 is taken as the z-axis direction, the long side direction of the base 101 is taken as the y-axis direction, and the short side direction of the base 101 is taken as the x-axis direction. The working principle of the parallel mechanism with degrees of freedom is described as follows:

The split-type five-degree-of-freedom parallel mechanism provided by the present invention selects two first moving pairs 11, two first telescopic rods 4 and a third rotating pair 13 as active pairs, and the two first telescopic rods 4 expand and contract in opposite directions, and cooperate with other The active pair can realize the freedom of movement of the moving platform 2 along the y-axis; the two first telescopic rods 4 can be extended and retracted in the same direction, and cooperate with the two first moving pairs 11 to realize the freedom of movement of the moving platform 2 along the x-axis; The first moving pair 11 moves in the same direction along the two first guide rails 102, and cooperates with other active pairs to realize the freedom of movement of the moving platform 2 along the z-axis; 3. Rotate around the z-axis, thereby enabling the moving platform 2 to obtain the rotational freedom around the z-axis; lock the two first moving pairs 11, and the two first telescopic rods 4 cooperate with the third rotating pair 13, so that the sub-platform can be divided 3 Move along the x-axis, thereby enabling the moving platform 2 to obtain rotational degrees of freedom around the y-axis; finally, the moving platform 2 can achieve a total of five degrees of freedom of movement in three directions and rotational degrees of freedom around the y and z axes .

Claims

A split-type five-degree-of-freedom parallel mechanism, characterized in that the parallel mechanism comprises a fixed platform (1), a moving platform (2), a first branch (I), a second branch (II) and a third branch chain (III);

Wherein, the fixed platform (1) comprises a base (101) fixed on the ground, two first guide rails (102), two first hinge supports (103), two first telescopic rods (4), a sub-platform (3) and a third hinged support (301); two first guide rails (102) are fixed on both ends of the upper surface of the fixed platform (1) in a symmetrical manner, and are perpendicular to the fixed platform (1); two A first hinged support (103) is fixed on both ends of one side of the fixed platform (1), and the rotation axis is perpendicular to the upper surface of the base (101); two ends of the sub-platform (3) are respectively fixed with a first Four hinged supports (302), each fourth hinged support (302) is respectively connected with one end of a first telescopic rod (4) to form a first rotating pair (5), and the other end of the first telescopic rod (4) It is connected with a first hinged support (103) to form a second rotating pair (6), and the rotation axes of the first rotating pair (5) and the second rotating pair (6) are parallel to each other; The first telescopic rod (4) is an active pair, which can realize the movement of the sub-platform (3) relative to the fixed platform (1), so that the mechanism has a split structure;

The moving platform (2) includes a platen (201), a second hinged support (203) and two first spherical hinge supports (202); a second hinged support (203) and two first spherical hinge supports The seat (202) is fixed on the bottom surface of the platen (201) in the shape of a zigzag, and the rotation axis of the second hinge support (203) is parallel to the center line of the two first spherical hinge supports (202);

The structures of the first branch (I) and the second branch (II) are identical and symmetrical, and both include a first connecting rod (7), a first sliding block (10), a first spherical hinge (8) and a first Two spherical hinges (9); wherein one end of the first connecting rod (7) is connected with a first spherical hinge support (202) fixed on the moving platform (2) through the first spherical hinge (8), and the other end is connected by The second spherical hinge (9) is connected to the second spherical hinge support (1001) fixed on the first sliding block (10), and the second spherical hinge support (1001) is fixedly connected to the first sliding block (10) the surface; the first sliding block (10) is installed on the first guide rail (102) in a way that can move up and down to form a first moving pair (11);

The third branch chain (III) is the second connecting rod (12); one end of the second connecting rod (12) is connected with the second hinge support (203) on the moving platform (2) to form a fourth rotating pair (14). ), and the other end is connected with the third hinged support (301) on the fixed platform (1) to form a third rotating pair (13).
The split-type five-degree-of-freedom parallel mechanism according to claim 1, wherein the base (101) adopts a rectangular plate-like structure.
The split-type five-degree-of-freedom parallel mechanism according to claim 1, characterized in that: the sub-platform (3) adopts a triangular plate-like structure.