A two-rotating and one-moving arc-shaped guide rail parallel mechanism with fixed drive

Abstract

The present invention relates to the field of industrial robots. The technical solution is: a parallel mechanism with two rotating and one moving arc guide rails that is fixed in drive, characterized in that: the parallel mechanism includes a frame, a moving platform, and three identical branches connected in parallel between the frame and the moving platform; the branches include arc moving sub-guide rails, moving sub-slide blocks, ball joints, connecting rods, and rotating subs that are sequentially connected between the frame and the moving platform; among the three branches, the center lines of the arc moving sub-guide rails in two branches are coplanar, and the plane where the center line of the arc moving sub-guide rail in the third branch is located is perpendicular to the plane where the center line of the arc moving sub-guide rails of the aforementioned two branches is located; the two arc moving sub-guide rails in the aforementioned two branches are symmetrically arranged about the plane where the center line of the arc moving sub-guide rail of the third branch is located. The parallel mechanism should have the advantages of fixed drive, fast operation speed, and good dynamic performance.

Description

Technical Field

[0001] The invention relates to the field of industrial robots, in particular to a two-rotating and one-moving arc-shaped guide rail parallel mechanism with fixed driving, which can be used for curved surface processing of large parts and the like. Background Art

[0002] In the field of mechanical manufacturing, grinding and other operations of curved surface parts can be achieved by installing a spindle head at the end of a traditional CNC machine tool. However, the serial open-loop structure of traditional machine tools will bring a series of problems, such as the surface processing accuracy cannot meet the requirements, the whole machine has large inertia, poor dynamic performance, and high manufacturing / maintenance costs.

[0003] Different from the open-loop structure of the serial mechanism, the parallel mechanism connects the fixed platform and the moving platform through two or more branches to form a special multi-closed-loop structure, which ensures that the parallel mechanism has the same degree of freedom while also having the advantages of compact structure, small motion inertia, high rigidity, and large load-bearing capacity. At the same time, unlike the structural feature of the serial mechanism where the motor is installed at each joint, the drive motor that realizes the movement of the mechanism in the parallel mechanism can be installed near the frame, and there are many passive joints that do not require the installation of motors. This feature makes the parallel mechanism have a higher operating speed and better dynamic characteristics. Based on the above advantages, parallel mechanisms have been widely studied and applied by researchers and the industrial community in recent years. Among them, the parallel mechanism with two rotations and one movement has been paid more attention and favored. It has been used as the skeleton of many high-end processing equipment and has been successfully applied to industrial fields such as grinding and polishing of complex curved surfaces in space and five-axis linkage processing.

[0004] While some two-rotation-one-movement parallel mechanisms have been successfully applied (WO 2006062466, US 4732525), there is still a problem: the drive motor is not installed on the frame, which will affect the operating speed of the mechanism and the processing accuracy of parts. For processing equipment based on two-rotation-one-movement parallel mechanisms, the ideal drive arrangement scheme should be that all branches in the parallel mechanism are driven by fixed motors, so as to reduce the overall motion mass, improve the dynamic performance and part processing accuracy, and reduce the difficulty of actual control. Therefore, it is necessary to propose a two-rotation-one-movement parallel mechanism with fixed drive, fast operating speed and good dynamic performance. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies in the above-mentioned background technology and to provide a two-rotating and one-moving arc-shaped guide rail parallel mechanism with fixed drive, which should have the advantages of fixed drive, fast operation speed and good dynamic performance.

[0006] The technical solution of the present invention is:

[0007] A drive fixed two rotating one moving arc guide parallel mechanism, characterized in that: the parallel mechanism comprises a frame, a moving platform and three identical branches connected in parallel between the frame and the moving platform;

[0008] The branch includes an arc-shaped moving pair guide rail, a moving pair slider, a ball joint, a connecting rod and a rotating pair which are sequentially connected between the frame and the moving platform;

[0009] Among the three branches, the center lines of the arc-shaped movable sub-guides in two branches are coplanar, and the plane where the center line of the arc-shaped movable sub-guide in the third branch lies is perpendicular to the plane where the center lines of the arc-shaped movable sub-guides in the aforementioned two branches lie; the two arc-shaped movable sub-guides in the aforementioned two branches are symmetrically arranged about the plane where the center line of the arc-shaped movable sub-guide in the third branch lies.

[0010] The center line of the arc-shaped movable secondary guide rail is an arc.

[0011] The moving pair is a driving pair; the driving mechanism of each moving pair is a ball screw mechanism driven by a motor.

[0012] A drive fixed two rotating one moving arc guide parallel mechanism, characterized in that: the parallel mechanism comprises a frame, a moving platform and three identical branches connected in parallel between the frame and the moving platform;

[0013] The branch includes an arc-shaped moving pair guide rail, a moving pair slider, a ball joint, a connecting rod and a rotating pair which are sequentially connected between the frame and the moving platform;

[0014] The planes where the center lines of the three arc-shaped movable auxiliary guide rails are located are perpendicular to each other; the center line of the arc-shaped movable auxiliary guide rail is an arc, and the centers of the center lines of the three arc-shaped movable auxiliary guide rails intersect at one point.

[0015] The moving pair is a driving pair; the driving mechanism of each moving pair is a ball screw mechanism driven by a motor.

[0016] A drive fixed two rotating one moving arc guide parallel mechanism, characterized in that: the parallel mechanism comprises a frame, a moving platform and three identical branches connected in parallel between the frame and the moving platform;

[0017] The branch includes a third arc-shaped moving pair guide rail, a third moving pair slider, a third ball joint, a third connecting rod and a third rotating pair which are sequentially connected between the frame and the moving platform;

[0018] The center lines of the three third arc-shaped movable secondary guide rails are in the same plane and are symmetrically arranged on the plane.

[0019] The center lines of the three third arc-shaped movable auxiliary guide rails are all arcs.

[0020] The centers of the three arcs intersect at one point.

[0021] The moving pair is a driving pair; the driving mechanism of each moving pair is a ball screw mechanism driven by a motor.

[0022] The beneficial effects of the present invention are:

[0023] The parallel mechanism proposed in the present invention can perform two rotations and one movement in space, has the advantages of fixed drive, fast operation speed, good dynamic performance and high rigidity, and can be used in fields such as complex curved surface processing in space. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the three-dimensional structure of the first embodiment of the present invention.

[0025] Figure 2 It is a schematic diagram of the three-dimensional structure of the second embodiment of the present invention.

[0026] Figure 3 for Figure 1 or Figure 2 Schematic diagram of the three-dimensional structure of the middle branch.

[0027] Figure 4 It is a schematic diagram of the three-dimensional structure of embodiment 3 of the present invention.

[0028] Figure 5 for Figure 4 Schematic diagram of the three-dimensional structure of the middle branch. DETAILED DESCRIPTION

[0029] The present invention will be further described below in conjunction with the accompanying drawings, but the present invention is not limited to the following embodiments.

[0030] Embodiment 1

[0031] like Figure 1 , 3 shows a driving fixed two rotating and one moving arc guide parallel mechanism, comprising a frame (omitted in the figure), a moving platform 1 and three identical branches connected in parallel between the frame and the moving platform.

[0032] Each branch includes an arc-shaped moving auxiliary guide rail 11, a moving auxiliary slider 12, a ball joint 13, a connecting rod 14 and a rotating pair 15 which are sequentially connected between the frame and the moving platform.

[0033] In this embodiment, the center lines of the arc-shaped moving sub-guide rails in the two branches are coplanar; the plane where the center line of the arc-shaped moving sub-guide rails in the third branch is located is perpendicular to the plane where the center lines of the arc-shaped moving sub-guide rails in the first two branches are located. The arc-shaped moving sub-guide rails in the first two branches are arranged symmetrically about the plane where the center line of the arc-shaped moving sub-guide rails in the third branch is located. Correspondingly, the rotation sub-axis lines in the first two branches are parallel to each other and perpendicular to the rotation sub-axis line in the third branch.

[0034] Preferably, the center line of the arc-shaped movable auxiliary guide rail is an arc.

[0035] In this embodiment, the driving pair is a moving pair on each branch, and a ball screw (omitted in the figure) can be selected as the driving method; when the driving pair moves, the mechanism performs three-degree-of-freedom motion with two rotations and one movement.

[0036] Embodiment 2

[0037] like Figure 2 , 3 shows a driving fixed two rotating and one moving arc guide parallel mechanism, comprising a frame (omitted in the figure), a moving platform 1 and three identical branches connected in parallel between the frame and the moving platform.

[0038] Each branch includes an arc-shaped moving auxiliary guide rail 11, a moving auxiliary slider 12, a ball joint 13, a connecting rod 14 and a rotating pair 15 which are sequentially connected between the frame and the moving platform.

[0039] In this embodiment, the planes where the center lines of the three arc-shaped moving auxiliary guide rails are located are perpendicular to each other; the center lines of the three arc-shaped moving auxiliary guide rails are all arcs, and the centers of the arcs intersect at one point. Correspondingly, the rotation auxiliary axes in the three branches intersect each other to form an equilateral triangle.

[0040] In this embodiment, the driving pair is a moving pair on each branch, and a ball screw (omitted in the figure) can be selected as the driving method; when the driving pair moves, the mechanism performs three-degree-of-freedom motion with two rotations and one movement.

[0041] Embodiment 3

[0042] like Figure 4 , 5 shows a driving fixed two rotating and one moving arc guide parallel mechanism, comprising a frame (omitted in the figure), a moving platform 1 and three identical branches connected in parallel between the frame and the moving platform.

[0043] Each branch includes a third arc-shaped movable auxiliary guide rail 21, a third movable auxiliary slider 22, a third ball joint 23, a third connecting rod 24 and a third rotating pair 25 which are sequentially connected between the frame and the moving platform.

[0044] In this embodiment, the center lines of the three third arc-shaped moving secondary guide rails are in the same plane; the center lines of the three third arc-shaped moving secondary guide rails are all arcs, and the three arcs are symmetrically arranged in the plane; their centers may intersect at one point, or not. The rotation secondary axes in the three branches also intersect in pairs to form an equilateral triangle.

[0045] In this embodiment, the driving pair is the third arc-shaped moving pair on each branch, and the driving method can be a ball screw (omitted in the figure); when the driving pair moves, the mechanism performs three-degree-of-freedom motion with two rotations and one movement.

Claims

1. A two-rotating and one-moving arc-shaped guide rail parallel mechanism with fixed drive, characterized in that: The parallel mechanism comprises a frame, a moving platform (1), and three identical branches connected in parallel between the auxiliary frame and the moving platform; The branch comprises an arc-shaped moving auxiliary guide rail (11), a moving auxiliary slider (12), a ball joint (13), a connecting rod (14) and a rotating pair (15) which are sequentially connected between the frame and the moving platform; Among the three branches, the center lines of the arc-shaped movable sub-guides in two branches are coplanar, and the plane where the center line of the arc-shaped movable sub-guide in the third branch lies is perpendicular to the plane where the center lines of the arc-shaped movable sub-guides in the aforementioned two branches lie; the two arc-shaped movable sub-guides in the aforementioned two branches are symmetrically arranged about the plane where the center line of the arc-shaped movable sub-guide in the third branch lies.

2. The two-rotating-one-moving arc-shaped guide rail parallel mechanism with fixed drive according to claim 1, characterized in that: The center line of the arc-shaped movable secondary guide rail is an arc.

3. A two-rotating and one-moving arc-shaped guide rail parallel mechanism with fixed drive, characterized in that: The parallel mechanism comprises a frame, a moving platform (1) and three identical branches connected in parallel between the auxiliary frame and the moving platform; The branch comprises an arc-shaped moving auxiliary guide rail (11), a moving auxiliary slider (12), a ball joint (13), a connecting rod (14) and a rotating pair (15) which are sequentially connected between the frame and the moving platform; The planes where the three arc-shaped movable auxiliary guide rails are located are perpendicular to each other; the center line of the arc-shaped movable auxiliary guide rail is an arc, and the centers of the three arc-shaped movable auxiliary guide rails intersect at one point.

4. A two-rotating and one-moving arc-shaped guide rail parallel mechanism with fixed drive, characterized in that: The parallel mechanism comprises a frame, a moving platform (1), and three identical branches connected in parallel between the auxiliary frame and the moving platform; The branch comprises a third arc-shaped movable pair guide rail (21), a third movable pair slider (22), a third ball joint (23), a third connecting rod (24) and a third rotating pair (25) which are sequentially connected between the frame and the movable platform; The center lines of the three third arc-shaped movable secondary guide rails are in the same plane and are symmetrically arranged on the plane.

5. The two-rotating-one-moving arc-shaped guide rail parallel mechanism with fixed drive according to claim 4, characterized in that: The center lines of the three third arc-shaped movable auxiliary guide rails are all arcs.

6. The two-rotating-one-moving arc-shaped guide rail parallel mechanism with fixed drive according to claim 5, characterized in that: The centers of the three arcs intersect at one point.

7. The two-rotating-one-moving arc-shaped guide rail parallel mechanism with fixed drive according to claim 1 or 2 or 3 or 4, characterized in that: The moving pair on each branch is a driving pair; the driving mechanism of each moving pair is a ball screw mechanism driven by a motor.

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