Space 6R multiple metamorphic mechanism

Abstract

A space 6R multiple metamorphic mechanism comprises two connecting rods and motion branch chains used for connecting the front ends and the rear ends of the two connecting rods. The two motion branch chains are respectively two triangular rods which are connected through a revolute pair B and a revolute pair E; the two ends of the front side movement branch chain are connected with the front ends of the two connecting rods through rotating pairs D and F correspondingly. The two ends of the rear side movement branch chain are connected with the rear ends of the two connecting rods through rotating pairs A and C correspondingly. And two sides of the revolute pairs B, E, D and F are provided with mechanical limiters. When the mechanism is unfolded and folded to the mechanical limiting fit of the two sides of the revolute pairs B, E and D, the mechanism moves to the first configuration bifurcation point, and at the moment, the mechanism has the two movement tendencies of unfolding and folding and translation at the same time. When the theta is continuously driven to rotate anticlockwise, the mechanism enters a translational motion mode; and when the rotating pair A anticlockwise rotates to theta = 180 degrees, the mechanism has two movement tendencies of translation and rotation at the same time. Therefore, three different motion modes of unfolding and folding, translation and rotation and mode switching can be achieved through one mechanism.

Description

Technical Field

[0001] The invention belongs to the field of mechanical technology and relates to a spatial 6R multiple cell-metamorphosis mechanism. Background Art

[0002] Metamorphic mechanisms can achieve different motion modes through their own structural reorganization without changing the constituent components, so as to achieve multi-functionality. Compared with traditional mechanisms with a single and fixed operating mode, metamorphic mechanisms have significant advantages in application scenarios with variable operating environments and limited number of constituent components due to their variable motion characteristics. Therefore, the research on reconfigurable mechanisms and reconfigurable robot technology, with metamorphic mechanism research as the main research content, has gradually become a hot topic in mechanism and robotics research. Compared with general metamorphic mechanisms, multiple metamorphic mechanisms can achieve multiple structural reorganizations and realize three or more different motion modes through a set of mechanisms. Therefore, they have richer motion switching capabilities than general metamorphic mechanisms. Compared with traditional metamorphic mechanisms that can only achieve single structural and kinematic mode switching, multiple metamorphic mechanisms can achieve multiple structural reorganizations and motion mode switching, and can be applied to more complex working scenes and more variable working tasks. It is a research branch in metamorphic mechanisms with great research prospects. Summary of the invention

[0003] In order to realize multi-mode operation of mechanical equipment in complex and changeable environments, the present invention proposes a spatial 6R multi-cell mechanism that can realize three different motion modes: extension and retraction, translation and rotation.

[0004] The spatial 6R multiple cell-metamorphosis mechanism of the present invention comprises a connecting rod A, a connecting rod B, and four branched connecting rods;

[0005] The front and rear ends of the connecting rod A are respectively designed with a front joint A and a rear joint A, and connecting holes are coaxially opened on the two joints, and the axes are parallel and perpendicular to the axis of the connecting rod A; a rectangular limiting protrusion is designed on the front side wall surface of the front joint A, and a limiting matching surface is designed on the limiting protrusion.

[0006] The connecting rod B is designed with a rear joint B at the rear end and a front joint B at the front end; the axes of the two cylindrical joints are parallel and perpendicular to the axis of the connecting rod B; a rectangular limiting boss is designed on the side of the front joint B, and a limiting mating surface is provided on the limiting boss;

[0007] Among the four branch chain links, a cylindrical joint A is designed on the rear end face of the branch chain link A, and a connecting hole is coaxially opened on the cylindrical joint A, and the axis of the connecting hole is perpendicular to the axis of the branch chain link A; a cylindrical joint B is designed on the front end face of the branch chain link A, and a connecting hole is opened on the cylindrical joint B, and the angle between the axis of the connecting hole and the axis of the cylindrical joint A is 60°; the front end face of the above-mentioned branch chain link A serves as a limit fitting surface.

[0008] A cylindrical joint C is designed on the rear end face of the branch link B, and a connecting hole is coaxially opened on the cylindrical joint C, and the axis of the connecting hole is perpendicular to the axis of the branch link B; a cylindrical joint D is designed on the front end face of the branch link B; a connecting hole is opened on the cylindrical joint D, and the angle between the axis of the connecting hole and the axis of the cylindrical joint C is 60°; the front end face of the branch link B serves as a limit fitting surface.

[0009] A cylindrical joint E is designed at the rear end of the branch chain link C, and a connecting hole is coaxially opened on the cylindrical joint E, and the axis of the connecting hole is perpendicular to the axis of the branch chain link C; a cylindrical joint F is designed at the rear end face of the branch chain link C; a connecting hole is opened on the cylindrical joint F, and the angle between the axis of the connecting hole and the axis of the cylindrical joint E is 60°; the rear end face and the front end face of the branch chain link C are both used as limit fitting surfaces.

[0010] A cylindrical joint F is designed on the front end face of the branch link D, and a connecting hole is opened on the axis of the cylindrical joint F, and the axis of the connecting hole is perpendicular to the branch link D; a limit piece is designed on the side of the rear end of the branch link D, and a connecting hole is opened on the limit piece, and the angle between the axis of the connecting hole and the axis of the cylindrical joint F is 60°; the front end face of the branch link D is used as a limit fitting surface; at the same time, a plane is designed on the circular boss as a limit fitting surface.

[0011] The rear end connecting hole of the cylindrical connecting rod A and the rear end connecting hole of the branch link A are hinged by a pin to form a revolute pair A; the front end connecting hole of the branch link A and the front end connecting hole of the branch link B are hinged by a pin to form a revolute pair B; the rear end connecting hole of the branch link B4 and the rear end connecting hole of the cylindrical connecting rod B are hinged to form a revolute pair C; the connection between the cylindrical connecting rod A and the left side moving branch of the cylindrical connecting rod B is completed; the front end connecting hole of the circular connecting rod A and the rear end connecting hole of the branch link C are hinged by a pin to form a revolute pair D; the front end connecting hole of the branch link C and the front end connecting hole of the branch link D are hinged by a pin to form a revolute pair E; the rear end connecting hole of the branch link D and the front end connecting hole of the cylindrical connecting rod B are hinged to form a revolute pair F, and the connection between the cylindrical connecting rod A and the right side moving branch of the cylindrical connecting rod B is completed.

[0012] The lengths of the branch chain links A, B, C and D are all equal, the lengths of the cylindrical links A and B are equal, and the length of the cylindrical links is twice the length of the branch chain links.

[0013] The above scheme obtains three motion modes: the expansion and contraction motion mode, the translation motion mode and the rotation motion mode, which are specifically:

[0014] In the expansion and contraction motion mode, the axes of each rotation pair meet the following requirements: the axes of motion of rotation pair A and rotation pair C intersect at O1, the axes of motion of rotation pair B and rotation pair E intersect, and the axes of motion of rotation pair D and rotation pair F intersect; the motion pair A is used as the motion input, and its included angle is θ. When the driving angle θ rotates counterclockwise, the mechanism gradually expands from the contracted position;

[0015] When the driving angle θ rotates counterclockwise to θ=90°, the whole mechanism unfolds into a square outline. At this time, the axes of the kinematic pairs satisfy: the axes of the revolute pairs A, C, D and F are parallel to each other, and the limit matching surfaces on both sides of the revolute pairs B, E and D are in contact. At this time, the mechanism moves to the first bifurcation position, and the mechanism has both expansion and contraction and translational movement tendencies; when θ is driven to rotate counterclockwise, the mechanism enters the translational movement mode;

[0016] When the revolute pair A is continuously driven to make θ>90°, the mechanism still performs the translational motion mode. During the translational motion, the axes of the revolute pairs A, C, D and F are parallel to each other, the limit matching surfaces on both sides of the revolute pairs B and E always keep in contact, the cylindrical connecting rod B always keeps parallel to the cylindrical connecting rod A, and the mechanism performs single-degree-of-freedom translational motion;

[0017] When the rotating pair A is continued to be driven to rotate counterclockwise to θ=180°, the geometric relationship of each moving pair is satisfied at this time: the axes of the rotating pair A, the rotating pair C, the rotating pair D and the rotating pair F are parallel to each other, the limit matching surfaces on both sides of the rotating pair B and the rotating pair C are in contact, and the movement axes of the rotating pair A and the rotating pair F coincide; at this time, the mechanism moves to the second bifurcation position, and has both translation and rotation movement tendencies; when the rotating pair A is continued to be driven to rotate counterclockwise so that θ>180°, the circular connecting rod B will rotate counterclockwise around the common straight line of the rotating pair A and the rotating pair F; continue to drive the rotating pair A to rotate counterclockwise, and the movement axes of the rotating pair A and the rotating pair F always remain coincident during the rotation of the cylindrical connecting rod B2.

[0018] Through the above method, six connecting rods are hinged by six revolute pairs AF to finally form a spatial 6R mechanism, and the rod lengths of the triangular rods A, B, C and D are equal, the rod lengths of the cylindrical connecting rods A and B are equal, and the rod length of the cylindrical connecting rod is twice the length of the triangular rod; the overall mechanism has three different motion modes: extension and retraction motion mode, translation motion mode and rotation motion mode.

[0019] The advantages of the present invention are:

[0020] 1. The spatial 6R multiple cell-metamorphosis mechanism of the present invention has three different motion modes: expansion and contraction, translation and rotation. A set of mechanisms can be used to realize a variety of different motion modes and their mutual conversion.

[0021] 2. The driving and switching of the three different motion modes of the spatial 6R multiple metamorphic mechanism of the present invention only require a single drive input and joint limit to be realized, without redundant drive, with a simple and compact structure and high driving efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is an overall structural diagram of a spatial 6R multiple cell mechanism of the present invention.

[0023] Figure 2 This is a diagram showing the composition of a circular connecting rod A of a spatial 6R multiple metamorphic mechanism of the present invention.

[0024] Figure 3 This is a diagram showing the structure of a circular connecting rod B of a spatial 6R multiple metamorphic mechanism of the present invention.

[0025] Figure 4 This is a diagram showing the structure of a triangular rod A of a spatial 6R multiple metamorphic mechanism of the present invention.

[0026] Figure 5 This is a diagram showing the structure of a triangular rod B of a spatial 6R multiple metamorphic mechanism of the present invention.

[0027] Figure 6 This is a diagram showing the structure of a triangular rod C of a spatial 6R multiple metamorphic mechanism of the present invention.

[0028] Figure 7 This is a diagram showing the structure of a triangular rod D of a spatial 6R multiple metamorphic mechanism of the present invention.

[0029] Figure 8 This is a diagram of a fully folded state of a spatial 6R multiple cell mechanism of the present invention.

[0030] Fig. 9 This is a diagram of the initial unfolding state of a spatial 6R multiple metamorphosis mechanism of the present invention.

[0031] Fig.10 This is a motion state diagram of a spatial 6R multiple metamorphosis mechanism of the present invention.

[0032] Fig.11 This is the first bifurcation configuration diagram of a spatial 6R multiple metamorphosis mechanism of the present invention.

[0033] Fig.12 This is a translational motion state diagram of a spatial 6R multiple metamorphic mechanism of the present invention.

[0034] Fig.13 This is the second bifurcation configuration diagram of a spatial 6R multiple metamorphosis mechanism of the present invention.

[0035] Fig.14 This is a rotational motion state diagram of a spatial 6R multiple metamorphic mechanism of the present invention.

[0036] In the figure:

[0037] 1-Cylindrical connecting rod A 2-Cylindrical connecting rod B 3-Triangular rod A

[0038] 4-Triangle rod B 5-Triangle rod C 6-Triangle rod D

[0039] 101-Front cylindrical joint A 102-Rear cylindrical joint A 103-Rectangular protrusion A

[0040] 201-Front cylindrical joint B 202-Rear cylindrical joint B 203-Rectangular protrusion B

[0041] 301-Triangle cylindrical joint A 302-Triangle rod cylindrical joint B 401-Triangle rod cylindrical joint C

[0042] 402-triangular rod cylindrical joint D 501-triangular rod cylindrical joint E 502-triangular rod cylindrical joint F

[0043] 601-Triangular rod cylindrical joint F 602-Circular boss DETAILED DESCRIPTION

[0044] The present invention is further described in detail below with reference to the accompanying drawings.

[0045] like Figure 1 As shown, a spatial 6R multiple cell-metamorphosis mechanism of the present invention is hinged by six motion links, including a cylindrical link A1, a cylindrical link B2, and four triangular bars, which are triangular bar A3, triangular bar B4, triangular bar C5 and triangular bar D6 respectively. The triangular bar A3 and triangular bar B4 form a rear branch chain, and the triangular bar C5 and triangular bar D6 form a front branch chain, which respectively realize the connection between the rear end and the front end of the cylindrical link A1 and the cylindrical link B2.

[0046] like Figure 2 As shown, the front and rear ends of the cylindrical connecting rod A1 are respectively designed with a front cylindrical joint A101 and a rear cylindrical joint A102; the two cylindrical joints are coaxially provided with connecting holes, and the axes are parallel and perpendicular to the axis of the cylindrical connecting rod A1, and are coplanar with the axis of the cylindrical connecting rod A1. Among them, a rectangular protrusion A103 is designed on the front side wall surface of the front cylindrical joint A101 for joint limit; one side of the rectangular protrusion A103 is located inside the surface A, serving as a limit matching surface.

[0047] like Figure 3 As shown, the rear end of the cylindrical connecting rod B2 is designed with a rear cylindrical joint B202, and the front end is designed with a front cylindrical joint B201; the axes of the two cylindrical joints are parallel and perpendicular to the axis of the cylindrical connecting rod B2, and are coplanar with the axis of the cylindrical connecting rod B2. A rectangular protrusion B203 is designed on the side of the front cylindrical joint B201 for joint limit; one side of the rectangular protrusion B203 is perpendicular to the axis of the cylindrical connecting rod B2, and passes through the axis of the front cylindrical joint B201, serving as a limit matching surface.

[0048] The structures of the triangular rods A3, B4, C5 and D6 are respectively as follows: Figure 4 to Figure 7The cross-sections of the four triangular rods are all regular triangles, and the specific structures of the four triangular rods are as follows:

[0049] like Figure 4 As shown, a triangular rod cylindrical joint A301 is designed at an edge of the rear end face of triangular rod A3, and the edge coincides with the axis of triangular rod cylindrical joint A301; a connecting hole is coaxially opened on triangular rod cylindrical joint A301. A triangular rod cylindrical joint B302 is designed at an edge of the front end face of triangular rod A3, and the axis of triangular rod cylindrical joint B302 coincides with the edge, and the angle between the axis of triangular rod cylindrical joint B302 and triangular rod cylindrical joint A301 is 60°; a connecting hole is coaxially opened on triangular rod cylindrical joint B302. The front end face of triangular rod A in the above structure serves as a limit fitting surface, which is parallel to the cross section of triangular rod A3.

[0050] like Figure 5 As shown, the rear end face of triangular rod B4 is designed with triangular rod cylindrical joint C401, the axis of triangular rod cylindrical joint C401 coincides with an edge of the rear end face of triangular rod B4; a connecting hole is coaxially opened on triangular rod cylindrical joint C401. The front end face of triangular rod B4 is designed with triangular rod cylindrical joint D402; the axis of triangular rod cylindrical joint D402 coincides with an edge of the front end face of triangular rod B4; and the angle between triangular rod cylindrical joint D402 and the axis of triangular rod cylindrical joint C401 is 60°; a connecting hole is coaxially opened on triangular cylindrical joint D402. The front end face of triangular rod B4 serves as a limit fitting surface and is parallel to the cross section of triangular rod B4.

[0051] like Figure 6 As shown, the rear end of triangular rod C5 is designed with triangular rod cylindrical joint E501, the axis of triangular rod cylindrical joint E501 coincides with an edge of the rear end face of triangular rod C5; a connecting hole is coaxially opened on triangular rod cylindrical joint E501. The front end face of triangular rod C5 is designed with triangular rod cylindrical joint F502; the axis of triangular rod cylindrical joint F502 coincides with an edge of the front end face of triangular rod C5; and the angle between triangular rod cylindrical joint F502 and the axis of triangular rod cylindrical joint E501 is 60°; a connecting hole is coaxially opened on triangular cylindrical joint F502. The rear end face and the front end face of triangular rod C5 are both used as limit fitting surfaces, parallel to the cross section of triangular rod C5.

[0052] like Figure 7As shown, the front end face of triangular rod D6 is designed with triangular rod cylindrical joint G601, and the axis of triangular rod cylindrical joint G601 coincides with an edge of the front end face of triangular rod D6; a connecting hole is coaxially opened on triangular rod cylindrical joint G601. A circular boss 602 is designed on the side of the rear end of triangular rod D6, and one side of the circular boss 602 is connected to triangular rod D6; a connecting hole is opened axially on the circular boss 602, so that the connecting hole is located outside the front end face of triangular rod D6, and the axis of the connecting hole is parallel to an edge of the rear end face of triangular rod D6, and the angle between the connecting hole and the axis of triangular rod cylindrical joint G601 is 60°. The front end face of the above-mentioned triangular rod D6 is used as a limit matching surface; at the same time, a plane is designed on the circular boss 602 as a limit matching surface; both limit matching surfaces are parallel to the cross section of triangular rod D6.

[0053] The cylindrical connecting rod A1, the cylindrical connecting rod B2, and the four triangular rods are connected to each other to form the spatial 6R multiple cell-metamorphosis mechanism of the present invention. The specific connection method is:

[0054] The rear connection hole of the cylindrical connecting rod A1 and the rear connection hole of the triangular rod A3 are hinged by a pin to form a revolute pair A; the front connection hole 302 of the triangular rod A3 and the front connection hole of the triangular rod B4 are hinged by a pin to form a revolute pair B, and the rotation of the revolute pair B is limited by the matching surfaces at the front ends of the two. The rear connection hole of the triangular rod B4 is hinged with the rear connection hole of the cylindrical connecting rod B2 to form a revolute pair C; thus, the connection between the cylindrical connecting rod A1 and the cylindrical connecting rod B2 and the rear motion branch chain is completed. The front end connecting hole of the circular connecting rod A1 and the rear end connecting hole of the triangular rod C5 are hinged by a pin to form a revolving pair D, and the rotation of the revolving pair D is limited by the cooperation of the limiting matching surface at the rear end of the triangular rod C5 and the front end of the circular connecting rod A1; the front end connecting hole of the triangular rod C5 and the front end connecting hole of the triangular rod D6 are hinged by a pin to form a revolving pair E, and the cooperation of the revolving pair E is limited by the cooperation of the limiting matching surfaces at the front ends of the two; the rear end connecting hole of the triangular rod D6 and the front end connecting hole of the cylindrical connecting rod B2 are hinged to form a revolving pair F, and the rotation of the revolving pair F is limited by the cooperation of the limiting matching surfaces at the front end of the cylindrical connecting rod B2 and the rear end of the triangular rod D6; at this point, the connection between the front side motion branches of the cylindrical connecting rod A1 and the cylindrical connecting rod B2 is completed. Therefore, the entire mechanism is a spatial 6R mechanism formed by six connecting rods hinged by six revolute pairs AF, and the rod lengths of the triangular rods A3, B4, C5 and D6 are equal, the rod lengths of the cylindrical connecting rods A1 and B2 are equal, and the rod length of the cylindrical connecting rod is twice the length of the triangular rod.

[0055] The spatial 6R multi-metamorphosis mechanism of the above structure has three different motion modes, namely, the expansion and contraction motion mode, the translation motion mode and the rotation motion mode. The motion modes of each mode are as follows:

[0056] A. Expand and contract movement pattern.

[0057] like Figure 8 As shown in FIG. 1 , the spatial 6R multiple metamorphic mechanism of the present invention is in a fully folded state. At this time, the mechanism is fully folded. When the mechanism is gradually unfolded from the fully folded state, the geometric relationship between the motion sub-axes in the mechanism is as follows: Fig. 9 As shown.

[0058] Under this configuration, each rotation in the mechanism

[0059] The axis of the moving pair meets the intersection of the motion axes of the rotating pair A and the rotating pair C at O1, the motion axes of the rotating pair B and the rotating pair E intersect at O2, and the motion axes of the rotating pair D and the rotating pair F intersect at O3. In addition, since the lengths of the rods meet the above relationship, the configuration of the spatial 6R multi-cell mechanism is a plane-symmetrical Bricard mechanism configuration, and the mechanism as a whole has the characteristics of expansion and contraction. The moving pair A is used as the motion input of the mechanism, and its angle is set to θ, that is, the angle between the axis of the cylindrical connecting rod A1 and the axis of the triangular rod A3. When the driving angle θ rotates counterclockwise, the entire mechanism will move from Figure 8 The folded configuration shown gradually expands, as Fig.10 shown.

[0060] like Fig.11 As shown in the figure, when the driving angle θ rotates counterclockwise to θ = 90°, the mechanism unfolds into a square outline. At this time, the axes of the kinematic pairs in the mechanism satisfy that the axes of the revolute pairs A, C, D, and F are parallel to each other, and the limit mating surfaces on both sides of the revolute pairs B, E, and D are all fitted, and the mechanism will move to the first bifurcation point. Fig.11 As shown in , when the mechanism is in this configuration, the instantaneous degree of freedom of the mechanism changes from a single degree of freedom expansion and contraction motion to 2, and the mechanism has both expansion and contraction and translation motion tendencies. Fig.11 In the configuration shown, since the limit mating surfaces of triangular rod A3 and triangular rod B4 fit together, the limit mating surfaces of triangular rod C5 and triangular rod D6 fit together, and the limit mating surfaces of cylindrical connecting rod A1 and triangular rod C fit together, when θ continues to be driven to rotate counterclockwise, due to the fit between the above-mentioned mechanical limits, the mechanism cannot continue to maintain the Bricard configuration and continue to expand and retract, and the mechanism will enter the translation motion mode.

[0061] like Fig.12As shown, when the revolving pair A continues to be driven so that θ>90°, the mechanism still performs the translational motion mode. As shown in the figure, during the translational motion, the axes of the revolving pairs A, C, D and F are parallel to each other, and the mechanical limits on both sides of the revolving pairs B and E always remain in close contact, that is, the revolving pairs B and E never rotate in this motion mode. Since the size of the mechanism satisfies that the rod lengths of the triangular rods AD are equal, the rod lengths of the cylindrical connecting rods A and B are equal, and the rod length of the cylindrical connecting rod is twice the length of the triangular rod, the axes of the four revolving pairs A, C, D, and F are parallel to each other. At this time, the mechanism is equivalent to a planar screw mechanism with four rods of equal length. During the movement of the mechanism, the cylindrical connecting rod B2 will always remain parallel to the cylindrical connecting rod A1, and the mechanism performs a single-degree-of-freedom translational motion.

[0062] like Fig.13 As shown, when the rotating pair A is continued to be driven to rotate counterclockwise to θ=180°, the geometric relationship of the kinematic pairs in the mechanism satisfies that the axes of the rotating pair A, rotating pair C, rotating pair D and rotating pair F are parallel to each other, the limiting mating surfaces on both sides of the rotating pair B and the rotating pair C are in contact, and the motion axes of the rotating pair A and the rotating pair F will coincide. At this time, the mechanism moves to the second configuration bifurcation point. The instantaneous degree of freedom of the mechanism suddenly changes from single degree of freedom translation motion to 2 again, and it has both translational and rotational motion tendencies. Fig.13 In the second bifurcation configuration shown in , when the revolute pair A is driven to rotate counterclockwise so that θ>180°, the mechanism cannot continue to achieve translational motion due to the fit between the limiting mating surfaces of the circular link B and the triangular rod D. Therefore, the circular link B will rotate counterclockwise around the common straight line of the revolute pair A and the revolute pair F. Fig.14 As shown, as the revolving pair A continues to be driven to rotate counterclockwise, the motion axes of the revolving pair A and the revolving pair F always remain coincident during the rotation of the cylindrical connecting rod B2.

[0063] The above process is a spatial 6R multiple metamorphosis mechanism from Figures 8 to 14 To achieve the process of expansion and contraction movement, translation movement and rotation movement, when the opposite movement is needed, that is, from Figure 14 to Figure 8 To realize the mechanism from rotational motion to translational motion and then to extension and retraction motion mode, it is only necessary to Fig.14 In the position shown, the rotating pair 7 is driven clockwise to rotate, so that the mechanism passes through Fig.13 The second configuration bifurcation point and Fig.11 The first configuration bifurcation point. At both configuration bifurcation points, the revolving pair A is driven clockwise. Fig.13 The second bifurcation point in the configuration utilizes the limit matching surface on the cylindrical connecting rod B2 and the triangular rod F6 to realize the transition of the mechanism from rotational motion to translational motion, while Fig.11At the first bifurcation point, the transition from translational motion to extension and retraction motion can be achieved by using the matching surfaces of the cylindrical connecting rod A1 and the triangular rod E5.

Claims

1. A spatial 6R multiple metamorphosis mechanism, characterized in that: It includes connecting rod A, connecting rod B, and four branch chain connecting rods; The front and rear ends of the connecting rod A are respectively designed with a front joint A and a rear joint A; the two joints are coaxially provided with connecting holes, and the axes are parallel and perpendicular to the axis of the connecting rod A; wherein a rectangular limiting protrusion is designed on the front side wall surface of the front joint A, and a limiting mating surface is designed on the limiting protrusion; The connecting rod B is designed with a rear joint B at the rear end and a front joint B at the front end; the axes of the two cylindrical joints are parallel and perpendicular to the axis of the connecting rod B; a rectangular limiting boss is designed on the side of the front joint B, and a limiting mating surface is provided on the limiting boss; Among the four branched chain links, a cylindrical joint A is designed on the rear end face of the branched chain link A, a connecting hole is coaxially opened on the cylindrical joint A, and the axis of the connecting hole is perpendicular to the axis of the branched chain link A; a cylindrical joint B is designed on the front end face of the branched chain link A, a connecting hole is opened on the cylindrical joint B, and the angle between the axis of the connecting hole and the axis of the cylindrical joint A is 60°; the front end face of the branched chain link A is used as a limit matching surface; The rear end face of the branch link B is designed with a cylindrical joint C, on which a connecting hole is coaxially opened, and the axis of the connecting hole is perpendicular to the axis of the branch link B; the front end face of the branch link B is designed with a cylindrical joint D; a connecting hole is opened on the cylindrical joint D, and the angle between the axis of the connecting hole and the axis of the cylindrical joint C is 60°; the front end face of the branch link B is used as a limit fitting surface; A cylindrical joint E is designed at the rear end of the branch link C, and a connecting hole is coaxially opened on the cylindrical joint E, and the axis of the connecting hole is perpendicular to the axis of the branch link C; a cylindrical joint F is designed at the rear end face of the branch link C; a connecting hole is opened on the cylindrical joint F, and the angle between the axis of the connecting hole and the axis of the cylindrical joint E is 60°; the rear end face and the front end face of the branch link C are both used as limit matching surfaces; A cylindrical joint F is designed on the front end face of the branch link D, and a connecting hole is opened on the axis of the cylindrical joint F, and the axis of the connecting hole is perpendicular to the branch link D; a limit piece is designed on the side of the rear end of the branch link D, and a connecting hole is opened on the limit piece, and the angle between the axis of the connecting hole and the axis of the cylindrical joint F is 60°; the front end face of the branch link D is used as a limit matching surface; at the same time, a plane is designed on the circular boss as a limit matching surface; The rear end connection hole of the cylindrical connecting rod A and the rear end connection hole of the branch chain connecting rod A are hinged by a pin to form a revolute pair A; the front end connection hole of the branch chain connecting rod A and the front end connection hole of the branch chain connecting rod B are hinged by a pin to form a revolute pair B; the rear end connection hole of the branch chain connecting rod B4 is hinged with the rear end connection hole of the cylindrical connecting rod B to form a revolute pair C; the connection between the cylindrical connecting rod A and the left side motion branch of the cylindrical connecting rod B is completed; the front end connection hole of the circular connecting rod A and the rear end connection hole of the branch chain connecting rod C are hinged by a pin to form a revolute pair D; the front end connection hole of the branch chain connecting rod C and the front end connection hole of the branch chain connecting rod D are hinged by a pin to form a revolute pair E; the rear end connection hole of the branch chain connecting rod D and the front end connection hole of the cylindrical connecting rod B are hinged to form a revolute pair F, and the connection between the cylindrical connecting rod A and the right side motion branch of the cylindrical connecting rod B is completed; The lengths of the branch chain links A, B, C and D are all equal, the lengths of the cylindrical links A and B are equal, and the length of the cylindrical links is twice the length of the branch chain links.

2. A spatial 6R multiple metamorphosis mechanism as claimed in claim 1, characterized in that: The cross-sections of the four branch links are all equilateral triangles; in the branch link A, the axis of the cylindrical joint A coincides with an edge of the rear end face of the branch link; the axis of the cylindrical joint B coincides with an edge of the front end face of the branch link; the limit fitting surface is parallel to the cross-section of the branch link A; In the branch link B, the axis of the cylindrical joint C coincides with an edge of the rear end face of the branch link B; the axis of the cylindrical joint D coincides with an edge of the rear end face of the branch link; the limit fitting surface is parallel to the cross section of the branch link B; In the branch link C, the axis of the cylindrical joint E coincides with an edge of the rear end face of the branch link C; the axis of the cylindrical joint F coincides with an edge of the rear end face of the branch link C; the limit fitting surface is parallel to the cross section of the branch link C; In the branch link D, the axis of the cylindrical joint F coincides with an edge of the front end surface of the branch link D; the limiter, the limiter has a connecting hole whose axis is parallel to an edge of the rear end surface of the branch link D; the two limit mating surfaces are parallel to the cross section of the branch link D.

3. A spatial 6R multiple metamorphosis mechanism as claimed in claim 1, characterized in that: It has three motion modes: extension and retraction motion mode, translation motion mode and rotation motion mode, specifically: In the expansion and contraction motion mode, the axes of each rotation pair meet the following requirements: the axes of motion of rotation pair A and rotation pair C intersect at O1, the axes of motion of rotation pair B and rotation pair E intersect, and the axes of motion of rotation pair D and rotation pair F intersect; the motion pair A is used as the motion input, and its included angle is θ. When the driving angle θ rotates counterclockwise, the mechanism gradually expands from the contracted position; When the driving angle θ rotates counterclockwise to θ=90°, the whole mechanism unfolds into a square outline. At this time, the axes of the kinematic pairs satisfy: the axes of the revolute pairs A, C, D and F are parallel to each other, and the limit matching surfaces on both sides of the revolute pairs B, E and D are in contact. At this time, the mechanism moves to the first bifurcation position, and the mechanism has both expansion and contraction and translational movement tendencies; when θ is driven to rotate counterclockwise, the mechanism enters the translational movement mode; When the revolute pair A is continuously driven to make θ>90°, the mechanism still performs the translational motion mode. During the translational motion, the axes of the revolute pairs A, C, D and F are parallel to each other, the limit matching surfaces on both sides of the revolute pairs B and E always keep in contact, the cylindrical connecting rod B always keeps parallel to the cylindrical connecting rod A, and the mechanism performs single-degree-of-freedom translational motion; When the rotating pair A is continued to be driven to rotate counterclockwise to θ=180°, the geometric relationship of each moving pair is satisfied at this time: the axes of the rotating pair A, the rotating pair C, the rotating pair D and the rotating pair F are parallel to each other, the limit matching surfaces on both sides of the rotating pair B and the rotating pair C are in contact, and the movement axes of the rotating pair A and the rotating pair F coincide; at this time, the mechanism moves to the second bifurcation position, and has both translation and rotation movement tendencies; when the rotating pair A is continued to be driven to rotate counterclockwise so that θ>180°, the circular connecting rod B will rotate counterclockwise around the common straight line of the rotating pair A and the rotating pair F; continue to drive the rotating pair A to rotate counterclockwise, and the movement axes of the rotating pair A and the rotating pair F always remain coincident during the rotation of the cylindrical connecting rod B2.

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