CN204209685U - A kind of novel two one-rotation parallel mechanisms - Google Patents

Abstract

The utility model discloses a novel two-rotation parallel mechanism, which is composed of a static platform, a dynamic platform and a first branch chain connecting the dynamic and static platforms, a second branch chain and a third branch chain, the first branch chain, The second branch chain and the third branch chain are symmetrically distributed in a space of 120 degrees. A novel two-rotation parallel mechanism of the utility model is composed of a connecting rod, a Hooke hinge and a revolving pair. Each branch chain is completely composed of an ordinary simple hinge. Excellent stiffness performance, can be used in satellite tracking and positioning, robot shoulder/wrist joint attitude adjustment and other occasions.

Description

A New Two-rotation Parallel Mechanism

technical field

The utility model relates to a two-rotation parallel mechanism, in particular to a two-rotation parallel mechanism with asymmetric branch chains.

Background technique

The two-rotation parallel mechanism has broad application prospects in the industrial field. It can be used in positioning and tracking devices for inter-satellite link satellites, robot shoulder/wrist joints, minimally invasive surgical robotic hands, etc. The above-mentioned application fields require that the two-rotation parallel mechanism is easy to assemble and Has a certain stiffness performance.

At present, the proposed parallel mechanism mainly has the following deficiencies: 1) The proposed two-rotation parallel mechanism has a complex structure and contains complex hinges. As described in patents CN102079090A and CN102294693A, the mechanism is composed of multiple branch chains, and the structure is complex; Contains complex hinges and is difficult to assemble; 2) The existing mechanism cannot provide sufficient rigidity to complete the required operations. The structural features of the mechanism described in patents CN102126212A and CN103624559A can be equivalent to a type of planar mechanism, which cannot be normal to the mechanism The direction provides sufficient support stiffness, so it cannot support satellites, robot arms, etc. to complete the required tracking and positioning operations.

In summary, the existing two-rotation parallel mechanism cannot meet the requirements of the above application fields.

Contents of the invention

The purpose of the utility model is to overcome the shortcomings of the prior art and provide a novel two-rotation parallel mechanism with a simple hinge structure and superior rigidity performance.

In order to achieve the above object, the technical scheme that the utility model adopts is:

A novel two-rotation parallel mechanism of the utility model is composed of a static platform, a dynamic platform, and a first branch chain connecting the dynamic and static platforms, a second branch chain and a third branch chain. The first branch chain, the The second branch chain and the third branch chain are distributed symmetrically in a space of 120 degrees;

The first branch chain includes a first static platform revolving pair installed on the static platform, the rotating shaft of the first static platform revolving pair is rotatably connected to one end of the lower arc-shaped rod, and the other end of the lower arc-shaped rod passes through the second An intermediate rotating pair is rotatably connected to one end of the upper arc-shaped rod, and the other end of the upper arc-shaped rod is rotatably connected to the moving platform through the first moving platform rotating pair. The first static platform rotating pair, the first intermediate rotating pair and the second A moving platform rotating auxiliary axes meet at the center point of the moving platform;

The second branch chain includes a second static platform Hooke hinge installed on the static platform, and the static platform is rotationally connected to one end of the first lower link through the second static platform Hooke hinge, and the first lower link The other end of the rod is rotatably connected to one end of the first upper link through the second intermediate rotating pair, and the other end of the first upper link is rotatably connected to the moving platform through the second moving platform Hooke hinge, and the second static platform Hooke The axis of the near frame of the hinge and the axis of the near frame of the Hooke hinge of the second moving platform meet at the center point of the moving platform, and the axis of the far frame of the Hooke hinge of the second static platform, the axis of the second intermediate rotating pair and the axis of the second moving platform The axes of the Hooke hinges are parallel to each other;

The third branch chain includes a third static platform rotating pair installed on the static platform, and the static platform is rotationally connected with one end of the second lower connecting rod through the third static platform rotating pair, and the second lower connecting rod is One end is rotatably connected to one end of the second upper link through the third intermediate rotating pair, and the other end of the second upper link is rotatably connected to the moving platform through the Hooke hinge of the third moving platform. The axis of rotation of the third static platform, The axis of the third intermediate rotating pair and the axis of the far frame of the Hooke hinge of the third moving platform are parallel to each other, and the axis of the near frame of the Hooke hinge of the third moving platform passes through the center point of the moving platform;

The axes of the revolving pair of the first moving platform, the near-frame axis of the Hooke hinge of the second moving platform and the near-frame axis of the Hooke hinge of the third moving platform are coplanar and symmetrically distributed at 120 degrees.

The utility model has the advantages of:

A novel two-rotation parallel mechanism of the utility model is composed of a connecting rod, a Hooke hinge and a revolving pair. Each branch chain is completely composed of an ordinary simple hinge. Excellent stiffness performance, can be used in satellite tracking and positioning, robot shoulder/wrist joint attitude adjustment and other occasions.

Description of drawings

Fig. 1 is a structural representation of a novel two-rotation parallel mechanism of the utility model;

Fig. 2 is the structural representation of the first branch chain in the mechanism shown in Fig. 1;

Fig. 3 is the structural representation of the second branch chain in the mechanism shown in Fig. 1;

Fig. 4 is the structural representation of the 3rd branch chain in the mechanism shown in Fig. 1;

Reference signs: static platform 1 first branch chain 2 second branch chain 3 third branch chain 4 moving platform 5 first static platform revolving pair 6 lower arc rod 7 first middle revolving pair 8 upper arc rod 9 first Moving platform revolving pair 10 Second static platform Hooke hinge 11 First lower link 12 Second intermediate revolving pair 13 First upper link 14 Second moving platform Hooke hinge 15 Third static platform revolving pair 16 Second lower link Rod 17 The third intermediate rotating pair 18 The second upper link 19 The third moving platform Hooke hinge 20 The center point of the moving platform P The first static platform rotating auxiliary axis a The first intermediate rotating auxiliary axis b The first moving platform rotating auxiliary axis c The second static platform Hooke hinge near frame axis d the second static platform Hooke hinge far frame axis e the second intermediate rotation axis f the second moving platform Hooke hinge far frame axis g the second dynamic platform Hooke hinge near frame axis h Axis of the third static platform rotating pair i Axis of the third intermediate rotating pair j Axis of the far frame of the third moving platform Hooke hinge k Axis of the near frame of the third moving platform Hooke hinge m

Detailed ways

The utility model is described in detail below in conjunction with specific embodiments.

As shown in the accompanying drawings, a novel two-rotation parallel mechanism of the present utility model consists of a static platform 1, a dynamic platform 5 and a first branch chain 2, a second branch chain 3 and a third branch chain 4 connecting the dynamic and static platforms. Composition, the first branch chain, the second branch chain and the third branch chain are distributed symmetrically in a space of 120 degrees;

The first branch chain 2 includes the first static platform rotating pair 6 installed on the static platform 1, the rotating shaft of the first static platform rotating pair is rotationally connected with one end of the lower arc rod 7, and the lower arc rod 7 The other end is rotationally connected to one end of the upper arc-shaped rod 9 through the first intermediate rotating pair 8, and the other end of the upper arc-shaped rod 9 is rotationally connected to the moving platform 5 through the first moving platform rotating pair 10, and the first static platform The rotating pair axis a, the first intermediate rotating pair axis b and the first moving platform rotating pair axis c converge at the center point P of the moving platform;

The second branch chain 3 includes a second static platform Hooke hinge 11 installed on the static platform 1, and the static platform 1 is rotationally connected with one end of the first lower link 12 through the second static platform Hooke hinge 11, The other end of the first lower link 12 is rotatably connected to one end of the first upper link 14 through the second intermediate rotating pair 13, and the other end of the first upper link 14 is connected to the moving platform through the second moving platform Hooke hinge 15. 5 Rotational connection, the second static platform Hooke hinge near-frame axis d and the second moving platform Hooke hinge near-frame axis h meet at the center point P of the moving platform, and the second static platform Hooke hinge The axis e of the far frame, the axis f of the second intermediate rotating pair and the axis g of the far frame of the second moving platform Hooke hinge are parallel to each other;

The third branch chain 4 includes a third static platform revolving pair 16 installed on the static platform 1, and the static platform 1 is rotatably connected to one end of the second lower link 17 through the third static platform revolving pair 16. The other end of the second lower link 17 is rotationally connected to one end of the second upper link 19 through the third intermediate rotating pair 18, and the other end of the second upper link 19 is rotated with the moving platform 5 through the third moving platform Hooke hinge 20 connection, the axis i of the third static platform revolving pair, the axis j of the third intermediate revolving pair and the axis k of the far frame of the Hooke hinge of the third moving platform are parallel to each other, and the axis m of the near frame of the Hooke hinge of the third moving platform passes through the The center point P of the moving platform;

The revolving pair axis c of the first moving platform, the hooke hinge proximal axis h of the second moving platform, and the hooke hinge proximal axis m of the third moving platform are coplanar and symmetrically distributed at 120 degrees.

The utility model is described in detail below again in conjunction with each figure.

As shown in Figure 1, a novel two-rotation parallel mechanism of the present invention consists of a static platform 1, a dynamic platform 5 and a first branch chain 2, a second branch chain 3 and a third branch chain 4 connecting the dynamic and static platforms. constitute. The first branch chain 2 , the second branch chain 3 and the third branch chain 4 are distributed symmetrically in a space of 120 degrees, and have inconsistent mechanical structure composition.

As shown in FIG. 2 , the first branch chain 2 is composed of the first static platform rotating pair 6 , the lower arc-shaped rod 7 , the first middle rotating pair 8 , the upper arc-shaped rod 9 and the first moving platform rotating pair 10 . The static platform 1 is rotationally connected to one end of the lower arc rod 7 through the first static platform rotating pair 6, and the other end of the lower arc rod 7 is connected to the upper arc rod 7 through the first intermediate rotating pair 8. One end of the shaped rod 9 is rotatably connected, and the other end of the upper arc-shaped rod 9 is rotatably connected with the moving platform 5 through the first moving platform rotating pair 10 . The first static platform rotation axis a, the first intermediate rotation axis b and the first moving platform rotation axis c converge at the center point P of the moving platform.

As shown in Figure 3, the second branch chain 3 is composed of the second static platform Hooke hinge 11, the first lower link 12, the second intermediate rotating pair 13, the first upper link 14 and the second dynamic platform Hooke Hinge 15 forms. The static platform 1 is rotationally connected to one end of the first lower link 12 through the second static platform Hooke hinge 11, and the other end of the first lower link 12 is connected to the second intermediate rotating pair 13. One end of the first upper link 14 is rotatably connected, and the other end of the first upper link 14 is rotatably connected to the moving platform 5 through the second moving platform Hooke hinge 15 . The near-frame axis d of the Hookee hinge on the second static platform and the near-frame axis h of the Hookee hinge on the second moving platform meet at the central point P of the moving platform, and the far-frame axis of the Hookee hinge on the second static platform e. The axis f of the second intermediate rotating pair and the axis g of the remote frame of the Hooke hinge of the second moving platform are parallel to each other.

As shown in Figure 4, the third branch chain 4 includes the third static platform rotating pair 16, the second lower connecting rod 17, the third intermediate rotating pair 18, the second upper connecting rod 19 and the third moving platform Hooke hinge 20. The static platform 1 is rotationally connected to one end of the second lower connecting rod 17 through the third static platform rotating pair 16, and the other end of the second lower connecting rod 17 is connected to the second lower connecting rod 17 through the third intermediate rotating pair 18. One end of the second upper link 19 is rotatably connected, and the other end of the second upper link 19 is rotatably connected to the moving platform 5 through the third moving platform Hooke hinge 20 . The axis i of the rotating pair of the third static platform, the axis j of the third intermediate rotating pair and the axis k of the far frame of the Hooke hinge of the third moving platform are parallel to each other, and the axis m of the near frame of the Hooke hinge of the third moving platform Pass through the center point P of the moving platform.

The axis c of the revolving pair of the first moving platform, the axis h of the Hooke hinge near the second moving platform, and the axis m of the Hooke hinge near the third moving platform are coplanar and symmetrically distributed at 120 degrees.

Under the action of the first static platform revolving pair 6 , the first intermediate revolving pair 8 and the first moving platform revolving pair 10 , the first branch chain has the ability to rotate in three degrees of freedom in space. Since the first static platform rotation axis a, the first intermediate rotation axis b, and the first moving platform rotation axis c converge at the center point P of the moving platform, the first branch chain The three-degree-of-freedom rotation center of 2 is the center point P of the moving platform, and its three rotation axes are respectively connected to the first static platform rotation axis a, the first intermediate rotation axis b, and the first moving platform rotation axis c coincides.

Under the action of the second static platform Hooke hinge 11, the second intermediate revolving pair 13 and the second moving platform Hooke hinge 15, the second branch chain has three degrees of freedom in space and two degrees of freedom in space. degree of mobility. The near-frame axis d of the Hookee hinge on the second static platform and the near-frame axis h of the Hookee hinge on the second moving platform meet at the central point P of the moving platform, and the far-frame axis of the Hookee hinge on the second static platform e. The axis f of the second intermediate rotating pair and the axis g of the far frame of the Hooke hinge of the second moving platform are parallel to each other and perpendicular to the axis d of the proximal frame of the Hooke hinge of the second static platform and the second moving platform The Hooke hinge is near the frame axis h, so the three rotation centers of the second branch chain are the center point P of the moving platform, and its three rotation axes are respectively connected to the second static platform Hooke hinge near the frame axis d and the second moving platform. The axis h of the near frame of the Hooke hinge coincides with the axis e of the far frame of the second static platform Hooke hinge. non-parallel straight lines.

Under the action of the third static platform revolving pair 16, the third intermediate revolving pair 18 and the third moving platform Hooke hinge 20, the third branch chain has the ability to rotate with two degrees of freedom in space and two degrees of freedom in space. degree of mobility. The hooke hinge near frame axis m of the third moving platform passes through the center point P of the moving platform, the rotation axis i of the third static platform, the third intermediate rotation axis j and the axis j of the third moving platform The axis k of the far frame of the Hooke hinge is parallel to each other and perpendicular to the axis m of the near frame of the Hooke hinge of the third moving platform, so the two rotation centers of the third branch chain 4 are the center point P of the moving platform, and the two rotation axes are respectively connected to The near-frame axis m of the Hooke hinge of the third moving platform is parallel to the far-frame axis k of the Hooke hinge of the third moving platform. non-parallel straight lines. (The definition of the center point of rotation and the moving plane can be found in the literature "Hervé JM. The Lie group of rigid body displacements, afundamental tool for mechanism design. Mech Mach Theory 1999; 34:719-730." (Hervé JM. Rigid body displacement Li Ziqun, Basic tools for mechanical design. Mechanics 1999; 34:719-730.")

Since the three rotation centers of the first branch chain 2, the three rotation centers of the second branch chain 3 and the two rotation centers of the third branch chain 4 are the center point P of the moving platform, in the first Under the joint action of the branch chain 2, the second branch chain 3 and the third branch chain 4, the moving platform 5 can realize the two-degree-of-freedom rotation whose center point of rotation is the center point P of the moving platform, and its rotation axis is respectively in line with The axis m of the near frame of the Hooke hinge of the third moving platform is parallel to the axis k of the far frame of the Hooke hinge of the third moving platform. Simultaneously, since the first branch chain 2 does not have the ability to move in space, the two-degree-of-freedom movement capabilities of the second branch chain 3 and the third branch chain 4 are limited by the first branch chain 2, and the moving platform 5 Only two rotational movements in space can be realized.

When the first static platform revolving pair 6, the second static platform Hooke hinge 11 and the third static platform revolving pair 16 are selected as drives, the mechanism of the present utility model is a new type of two-stage redundant drive. Rotating parallel mechanism; when two kinematic pairs in the first static platform revolving pair 6, the second static platform Hooke hinge 11 and the third static platform revolving pair 16 are randomly selected as drives, the utility model The mechanism is a new type of two-rotation parallel mechanism with non-redundant drive.

A new two-rotation parallel mechanism of the utility model is composed of three branch chains with different structures, each branch chain is completely composed of ordinary hinges, that is, revolving pairs and Hooke hinges, and each branch chain is completely composed of ordinary simple hinges. Simple and easy to assemble; because there is no special complex hinge inside the mechanism, the mechanism has a certain rigidity performance, so a new type of two-rotation parallel mechanism of the utility model can meet the requirements of satellite positioning tracking, robot arm attitude adjustment, etc. for the rotation parallel mechanism .

The above description of the utility model is only illustrative rather than restrictive, so the implementation of the utility model is not limited to the above specific implementation. If a person of ordinary skill in the art is inspired by it and makes other changes or modifications without departing from the gist of the utility model and the protection scope of the claims, all of them belong to the protection scope of the utility model.

Claims (1)

1. A novel two-rotation parallel mechanism is characterized in that: it consists of a static platform, a dynamic platform and the first branch chain connecting the dynamic and static platforms, the second branch chain and the third branch chain, the first branch chain , the second branch chain and the third branch chain are distributed symmetrically in a space of 120 degrees; The first branch chain includes a first static platform revolving pair installed on the static platform, the rotating shaft of the first static platform revolving pair is rotatably connected to one end of the lower arc-shaped rod, and the other end of the lower arc-shaped rod passes through the second An intermediate rotating pair is rotatably connected to one end of the upper arc-shaped rod, and the other end of the upper arc-shaped rod is rotatably connected to the moving platform through the first moving platform rotating pair. The first static platform rotating pair, the first intermediate rotating pair and the second The axes of the rotary axes of a moving platform meet at the center point of the moving platform; The second branch chain includes a second static platform Hooke hinge installed on the static platform, and the static platform is rotationally connected to one end of the first lower link through the second static platform Hooke hinge, and the first lower link The other end of the rod is rotatably connected to one end of the first upper link through the second intermediate rotating pair, and the other end of the first upper link is rotatably connected to the moving platform through the second moving platform Hooke hinge, and the second static platform Hooke The axis of the near frame of the hinge and the axis of the near frame of the Hooke hinge of the second moving platform meet at the center point of the moving platform, and the axis of the far frame of the Hooke hinge of the second static platform, the axis of the second intermediate rotating pair and the axis of the second moving platform The axes of the Hooke hinges are parallel to each other; The third branch chain includes a third static platform rotating pair installed on the static platform, and the static platform is rotationally connected with one end of the second lower connecting rod through the third static platform rotating pair, and the second lower connecting rod is One end is rotatably connected to one end of the second upper link through the third intermediate rotating pair, and the other end of the second upper link is rotatably connected to the moving platform through the Hooke hinge of the third moving platform. The axis of rotation of the third static platform, The axis of the third intermediate rotating pair and the axis of the far frame of the Hooke hinge of the third moving platform are parallel to each other, and the axis of the near frame of the Hooke hinge of the third moving platform passes through the center point of the moving platform; The axes of the revolving pair of the first moving platform, the near-frame axis of the Hooke hinge of the second moving platform and the near-frame axis of the Hooke hinge of the third moving platform are coplanar and symmetrically distributed at 120 degrees.