Spatial three-translation and one-rotation parallel mechanism

Abstract

The invention relates to a spatial parallel mechanism, in particular to a spatial three-translation and one-rotation parallel mechanism which comprises a base, a moving platform and at least three branch chains, the moving platform is arranged above the base, and the at least three branch chains are connected between the moving platform and the base in parallel; each branch chain comprises a parallel four-connecting-rod support arm and a tail-end connecting rod, the lower end of the parallel four-connecting-rod support arm is hinged to the base, the upper end of the parallel four-connecting-rod support arm is hinged to one end of the tail-end connecting rod, the other end of the tail-end connecting rod is hinged to the movable platform, and the swing direction of the tail-end connecting rod is perpendicular to the swing direction of the parallel four-connecting-rod support arm and is parallel to the plane of the base; all the branch chains act synchronously, so that the movable platform can achieve three-degree-of-freedom translational motion and rotary motion around the vertical axis. The multi-branch parallel mechanism has the characteristics that the moving branch chains are simple in movement and can be decoupled in movement, and the multi-branch parallel mechanism is small in degree of freedom and high in rigidity, and the precision and quality of the mechanism in the operation process are easily guaranteed.

Description

Technical Field

[0001] The invention relates to a spatial parallel mechanism, in particular to a spatial three-translation-one-rotation parallel mechanism. Background Art

[0002] At present, spatial parallel mechanisms are widely used in industrial fields such as handling, sorting, gluing, packaging and welding due to their compact structure, few degrees of freedom, easy integration and high movement speed. With the complex and changeable working conditions in modern production, more flexible or multi-degree-of-freedom parallel mechanisms are needed to meet work requirements. However, the current SCARA robot has low rigidity, the H4 parallel mechanism is prone to singular configurations, and the three-translation-one-rotation parallel mechanisms such as I4, Par4, Heli4, and X4 still have problems such as complex structure, large size, high kinematic coupling and complex control, which makes it difficult to meet the application requirements of lightweight, large load, simple control and working in unstructured environments. Summary of the invention

[0003] In view of the above problems, the purpose of the present invention is to provide a spatial three-translation and one-rotation parallel mechanism to solve the problems that the existing parallel mechanism has a complex structure, a large volume, and is difficult to apply in unstructured environments.

[0004] In order to achieve the above object, the present invention adopts the following technical solutions:

[0005] The present invention provides a spatial three-translation one-rotation spatial parallel mechanism, comprising a base, a moving platform and at least three branch chains, wherein the moving platform is arranged above the base, and at least three branch chains are connected in parallel between the moving platform and the base;

[0006] The branch chain includes a parallel four-link support arm and an end link, the lower end of the parallel four-link support arm is hinged to the base, the upper end is hinged to one end of the end link, the other end of the end link is hinged to the moving platform, and the swing direction of the end link is perpendicular to the swing direction of the parallel four-link support arm and parallel to the upper plane of the base;

[0007] The branches move synchronously, which can realize the three-degree-of-freedom translation movement of the moving platform and one rotation movement around the vertical axis.

[0008] The branch chains are arranged along the circumferential direction, and the parallel four-bar linkage arms in each of the branch chains are not coplanar.

[0009] The parallel four-link support arm comprises at least two parallel four-link units connected in series.

[0010] The parallel four-link support arm comprises a first parallel four-link unit and a second parallel four-link unit connected in series in sequence;

[0011] The first parallel four-bar linkage unit includes a branch link I, a branch link II and a branch link III, wherein the branch link I and the branch link II are arranged in parallel, and the lower ends of the branch links are hinged to the base, the upper ends of the branch links I and the branch links II are respectively hinged to the two ends of the branch link III, and the branch link III is parallel to the base.

[0012] The second parallel four-bar linkage unit includes a branch link IV, a branch link V and a branch link VI, wherein the branch link IV and the branch link VI are arranged in parallel, and the lower ends are respectively hinged to the two ends of the branch link III, the upper ends of the branch link IV and the branch link VI are respectively hinged to the two ends of the branch link V, the branch link V is parallel to the branch link III, the end link is parallel to the base, and one end is hinged to the branch link V.

[0013] A driving component for driving the branch chain to move is arranged on the rotating joint of each branch chain.

[0014] The advantages and beneficial effects of the present invention are as follows: a spatial three-translation and one-rotation parallel mechanism provided by the present invention utilizes the parallel transmission principle of a spatial linkage mechanism to realize translational motion in the x, y, and z directions of space and rotational motion around the z direction, and has the advantages of small structural size, simple mechanism, simple control, strong load capacity, high rigidity and fast response speed. The present invention is suitable for unstructured environments, is easy to implement, and has a wide range of uses. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of a spatial three-translation-one-rotation parallel mechanism of the present invention;

[0016] Figure 2 It is a schematic diagram of the structure of the branched chain in the present invention.

[0017] In the figure: 1-base, 2-branch chain, 3-moving platform, 201-branch chain link I, 202-branch chain link II, 203-branch chain link III, 204-branch chain link IV, 205-branch chain link V, 206-branch chain link VI, 207-end link, S1-parallelogram mechanism rotation axis direction, S2-end link outer side rotation axis direction, S3-end link inner side rotation axis direction. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0019] like Figure 1 to Figure 2As shown, the present invention provides a spatial three-translation-one-rotation parallel mechanism, comprising a base 1, a moving platform 3 and at least three branch chains 2, wherein the moving platform 3 is arranged above the base 1, and at least three branch chains 2 are connected in parallel between the moving platform 3 and the base 1; the branch chain 2 comprises a parallelogram arm and an end link 207, the lower end of the parallelogram arm is hinged to the base 1, the upper end is hinged to one end of the end link 207, the other end of the end link 207 is hinged to the moving platform 3, and the swing direction of the end link 207 is perpendicular to the swing direction of the parallelogram arm and parallel to the upper plane of the base 1. Each branch chain 2 swings synchronously, which can realize three-degree-of-freedom translation and one rotation around the vertical axis.

[0020] In the embodiment of the present invention, the branches 2 are arranged along the circumferential direction, and the parallel four-bar linkage arms in each branch chain 2 are not coplanar, so as to ensure that each parallel four-bar linkage arm can swing simultaneously. The number of branches 2 can be greater than three, forming a redundant constraint parallel mechanism, and multiple branches 2 are connected in parallel to realize the translational motion of the dynamic platform 3 in three directions and the rotational motion around the vertical axis.

[0021] Specifically, the parallel four-link support arm includes at least two parallel four-link units connected in series.

[0022] like Figure 2 As shown, in an embodiment of the present invention, the parallel four-bar linkage arm includes a first parallel four-bar linkage unit and a second parallel four-bar linkage unit connected in series in sequence; the first parallel four-bar linkage unit includes a branch link Ⅰ201, a branch link Ⅱ202 and a branch link Ⅲ203, wherein the branch link Ⅰ201 and the branch link Ⅱ202 are arranged in parallel, and the lower ends of the branch links Ⅰ201 and the branch link Ⅱ202 are hinged to the base 1, the upper ends of the branch links Ⅰ201 and the branch links Ⅱ202 are respectively hinged to the two ends of the branch link Ⅲ203, and the branch link Ⅲ203 is parallel to the base 1, and the base 1, the branch links Ⅰ201, the branch links Ⅱ202 and the branch links Ⅲ203 form a first parallel four-bar linkage unit.

[0023] The second parallel four-bar linkage unit includes a branch link IV204, a branch link V205 and a branch link VI206, wherein the branch link IV204 and the branch link VI206 are arranged in parallel, and the lower ends are respectively hinged to the two ends of the branch link III203, the upper ends of the branch link IV204 and the branch link VI206 are respectively hinged to the two ends of the branch link V205, the branch link V205 is parallel to the branch link III203, and the branch link III203, the branch link IV204, the branch link V205 and the branch link VI206 form the second parallel four-bar linkage unit. One end of the terminal link 207 is hinged to the branch link V205, and the terminal link 207 rotates horizontally in a direction perpendicular to the parallelogram arm, that is, the outer rotation axis direction S2 of the terminal link is the same as the inner rotation axis direction S3 of the terminal link, and is parallel to the z-axis. The rotation axis direction S1 of the parallelogram mechanism is parallel to the x-axis.

[0024] Furthermore, a driving component for driving the movement of the branch chain 2 is disposed on the rotating joint of each branch chain 2. In this embodiment, the lower end joint of each branch chain 2 is connected to a motor disposed on the base 1, and the motor is used to drive the branch chain 2 to swing.

[0025] In this embodiment, three branch chains 2 are connected in parallel between the base 1 and the moving platform 3. The three branch chains 2 are arranged along the circumferential direction but are not parallel, forming a spatial parallel mechanism with high rigidity, thereby improving the stability of the moving platform 3 during movement and the reliability of operation.

[0026] The present invention provides a spatial three-translation one-rotation parallel mechanism, whose working principle is:

[0027] Through two parallel four-link arms connected in series, two degrees of freedom translational motion along the y and z directions are formed, and after the end link 207 with two rotating pairs in the same direction is connected in series, the degrees of freedom of translational motion in the y and z directions and rotational motion in the z direction are obtained. By distributing the three branches 2 along the circumferential direction, the translational motion of the moving platform 3 in the x, y, and z directions and the rotational motion around the z direction can be realized after multiple branches are connected in parallel. The three driving motors are arranged on the rotation joints of the three branches 2 respectively, and the driving mechanism can realize the three-degree-of-freedom motion in space.

[0028] The present invention provides a spatial three-translation and one-rotation parallel mechanism, which realizes three-translation and one-rotation motion by utilizing the parallel transmission principle of a spatial linkage mechanism. The mechanism has the advantages of compact size, few degrees of freedom, high rigidity, simple control, strong load capacity, simple motion, low coupling degree and decoupling motion, and can easily ensure the accuracy and quality of the mechanism during operation, meet the application requirements of lightweight, large load, simple control and working in unstructured environments, and can be used in packaging production lines, loading and unloading production lines, high-precision position adjustment platforms, etc., to improve operating efficiency and safety.

[0029] The above description is only an embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, expansion, etc. made within the spirit and principle of the present invention are included in the protection scope of the present invention.

Claims

1. A spatial three-translation-one-rotation parallel mechanism, characterized in that: It comprises a base (1), a moving platform (3) and at least three branch chains (2), wherein the moving platform (3) is arranged above the base (1), and the at least three branch chains (2) are connected in parallel between the moving platform (3) and the base (1); The branch chain (2) comprises a parallelogram support arm and an end link (207), wherein the lower end of the parallelogram support arm is hinged to the base (1), the upper end is hinged to one end of the end link (207), the other end of the end link (207) is hinged to the moving platform (3), and the swing direction of the end link (207) is perpendicular to the swing direction of the parallelogram support arm and parallel to the upper plane of the base (1); The branch chains (2) move synchronously, so that the moving platform (3) can realize three-degree-of-freedom translation movement and one rotation movement around a vertical axis.

2. The spatial three-translation-one-rotation parallel mechanism according to claim 1, characterized in that: The branch chains (2) are arranged along the circumferential direction, and the parallel four-link support arms in each branch chain (2) are not coplanar.

3. The spatial three-translation-one-rotation parallel mechanism according to claim 1, characterized in that: The parallel four-link support arm comprises at least two parallel four-link units connected in series.

4. The spatial three-translation-one-rotation parallel mechanism according to claim 3, characterized in that: The parallel four-link support arm comprises a first parallel four-link unit and a second parallel four-link unit connected in series in sequence; The first parallel four-bar linkage unit comprises a branch link I (201), a branch link II (202) and a branch link III (203), wherein the branch link I (201) and the branch link II (202) are arranged in parallel, and the lower ends of the branch links I (201) and the branch link II (202) are hinged to the base (1), the upper ends of the branch links I (201) and the branch link II (202) are respectively hinged to the two ends of the branch link III (203), and the branch link III (203) is parallel to the base (1).

5. The spatial three-translation-one-rotation parallel mechanism according to claim 4, characterized in that: The second parallel four-bar linkage unit comprises a branch link IV (204), a branch link V (205) and a branch link VI (206), wherein the branch link IV (204) and the branch link VI (206) are arranged in parallel, and the lower ends of the branch link IV (204) and the branch link VI (206) are respectively hinged to the two ends of the branch link III (203), the upper ends of the branch link IV (204) and the branch link VI (206) are respectively hinged to the two ends of the branch link V (205), the branch link V (205) is parallel to the branch link III (203), and the end link (207) is parallel to the base (1), and one end is hinged to the branch link V (205).

6. The spatial three-translation-one-rotation parallel mechanism according to claim 1, characterized in that: A driving component for driving the branch chain (2) to move is arranged on the rotating joint of each branch chain (2).

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