A variable stiffness joint for a magnetic pulley robot

Abstract

A magnetic pulley robot variable stiffness joint comprises an upper arm carrier, an elbow joint carrier, a forearm, a pulley block and a rope winch, wherein the upper arm carrier is connected to the elbow joint carrier, which is connected to the forearm, and the elbow joint carrier is connected to the forearm through a pulley block, and the rope winch is arranged on the upper arm carrier; a flexible permanent magnetic variable stiffness mechanism is arranged on the upper arm carrier; 1. The assembly structure is made more compact. 2. The circuits in the forearm joint can be safely arranged inside it without being affected by the joint movement. 3. The present invention can place the drive unit and the variable stiffness joint at the rear in specific use. Since the parallel structure is selected in the design, when constructing a multi-degree-of-freedom joint, the disadvantage of the series structure that the stiffness change ability is insufficient due to the superposition of the inertia of multiple degrees of freedom is optimized. A dual-structure control is designed, which greatly improves the timeliness of the joint control ability.

Description

Technical Field

[0001] The invention belongs to the technical field of flexible variable stiffness robots, and relates to a variable stiffness joint for a flexible parallel antagonistic robot, and is particularly suitable for the construction of single / multi-degree-of-freedom variable stiffness robot joints. Background Art

[0002] Robot technology has been increasingly used in industrial production, medical services, humanistic entertainment and other fields, and its contact with people has become more frequent and close. Therefore, people are paying more and more attention to the issue of human-machine interaction.

[0003] The main difference between variable stiffness robot joints and traditional rigid joints is that elastic elements with adjustable stiffness are added to the overall structure, which enhances the adaptability to unstructured environments, better meets the needs of structural stability and compliance, and can reduce a large amount of energy consumption, which can enhance human-machine safety and environmental adaptability. Among them, the parallel variable stiffness joint using rope drive is closest to the human muscle drive method. Nonlinear springs are used on both sides of the joint, and the expansion and contraction of the springs are controlled by dual motors to adjust the joint position and output torque to achieve joint stiffness and position control. At present, the main problems that restrict the development of parallel rope-driven variable stiffness joints are that when controlling the joint stiffness, energy needs to be consumed continuously, so its energy utilization efficiency is not high. Therefore, it is of great significance to design a variable stiffness joint with a wide range of stiffness changes, small size, light weight, high joint stiffness adjustment ability and driving ability to solve the problem of high energy consumption of parallel rope-driven robots. Summary of the invention

[0004] Purpose of the invention:

[0005] The purpose of the present invention is to provide a variable stiffness joint that improves the joint stiffness adjustment capability and driving capability and reduces the joint volume. The purpose is to solve the problems that have existed in the past. The variable stiffness joint is convenient for the drive unit and the variable stiffness unit to be rear-mounted, and the magnetic pulley group structure is adopted to further enhance the stiffness adjustment capability and driving capability of the variable stiffness joint.

[0006] Technical solution:

[0007] A flexible permanent magnet variable stiffness robot joint, characterized in that it comprises a boom carrier 2, an elbow joint carrier 3, a forearm, a pulley block 5 and a rope winch, the boom carrier 2 is connected to the elbow joint carrier 3 and the forearm, the elbow joint carrier 3 is connected to the forearm through the pulley block 5, and the rope winch 27 is arranged on the boom carrier 2; a flexible permanent magnet variable stiffness mechanism is arranged on the boom carrier 2;

[0008] There are two rope winches, namely a first rope winch 27-1 and a second rope winch 27-2, and there are two flexible permanent magnet variable stiffness mechanisms, namely a first flexible permanent magnet variable stiffness mechanism and a second flexible permanent magnet variable stiffness mechanism;

[0009] The flexible permanent magnet variable stiffness mechanism comprises a fixed seat 8 and a movable slide seat 16;

[0010] The fixed seat 8 includes two vertical plates 8-1 and a connecting plate 8-2 connecting the two vertical plates 8-1. The movable slide seat 16 is a "↓"-shaped structure composed of a sliding rod 16-2 and a conical base 16-1. The conical base 16-1 is arranged at the lower end of the sliding rod 16-2. The upper end of the sliding rod 16-2 passes through the connecting plate 8-2 and can move up and down relative to the connecting plate 8-2.

[0011] A pulley 12 is disposed at the upper end of the sliding rod 16-2, and a fixed pulley is disposed at the top of each of the two vertical plates 8-1, namely, a first fixed pulley 7 and a second fixed pulley 11;

[0012] A first conical permanent magnet ring 13 is provided at the bottom of the connecting plate 8-2, and a second conical permanent magnet ring 14 corresponding to the first conical permanent magnet ring 13 is provided at the upper end of the conical base 16-1;

[0013] The rope wound on the first rope winch 27-1 is connected to the pulley block 5 after passing through the upper end of the first fixed pulley 7, the lower end of the pulley 12 and the upper end of the second fixed pulley 11 in the first flexible permanent magnet variable stiffness mechanism in sequence;

[0014] The rope wound on the second rope winch 27 - 2 is connected to the pulley block 5 after passing through the upper end of the first fixed pulley 7 , the lower end of the pulley 12 and the upper end of the second fixed pulley 11 in the second flexible permanent magnet variable stiffness mechanism in sequence.

[0015] The inner sides of the two vertical plates 8 - 1 are provided with movable slide grooves 15 or movable slide rails. The left and right ends of the conical base 16 - 1 extend into the movable slide grooves 15 or are provided on the movable slide rails and can move up and down along the movable slide grooves 15 or the movable slide rails.

[0016] The pulley block 5 includes a first joint displacement guide block 30 and a second joint displacement guide block 21, wherein the arcuate edge A of the first joint displacement guide block 30 contacts the arcuate edge B of the second joint displacement guide block 21, so that the arcuate edge B of the second joint displacement guide block 21 can roll on the arcuate edge A of the first joint displacement guide block 30;

[0017] The first guide rod 19-1, the second guide rod 19-2, the fourth guide rod 19-4 and the sixth guide rod 19-6 are vertically arranged on the side of the first joint displacement guide block 30; the first guide rod 19-1, the second guide rod 19-2 and the fourth guide rod 19-4 are arranged in a three-point manner, and the sixth guide rod 19-6 is located at the arc center position of the arc along A of the first joint displacement guide block 30, and the third guide rod 19-3, the fifth guide rod 20 and the seventh guide rod 19 are vertically arranged on the side of the second joint displacement guide block 21; the axes of the third guide rod 19-3, the fifth guide rod 20 and the seventh guide rod 19 are located on the same straight line. The third guide rod 19-3, the fifth guide rod 20 and the seventh guide rod 19 are arranged in a three-point manner, and the seventh guide rod 19 is located at the arc center of the arc B of the second joint displacement guide block 21; the first rope 6-1 led out from the upper end of the second fixed pulley 11 in the first flexible permanent magnet variable stiffness mechanism is passed around the upper end of the first guide rod 19-1, then passed around the lower end of the second guide rod 19-2, and then passed around the lower end of the third guide rod 19-3, and then repeatedly wound between the second guide rod 19-2 and the third guide rod 19-3, and finally the first rope 6-1 is fixed on the second guide rod 19-2 or the third guide rod 19-3;

[0018] The second rope 6-2 led out from the upper end of the second fixed pulley 11 in the second flexible permanent magnet variable stiffness mechanism passes through the lower end of the first guide rod 19-1, then passes through the upper end of the fourth guide rod 19-4, and then passes through the fifth guide rod 20, and then repeatedly wraps around the fourth guide rod 19-4 and the fifth guide rod 20, and finally is fixed on the fourth guide rod 19-4 or the fifth guide rod 20;

[0019] The rear end of the joint positioning block 17 is sleeved on the sixth guide rod 19 - 6 and can rotate around the sixth guide rod 19 - 6 as an axis, and the front end of the joint positioning block 17 is sleeved on the seventh guide rod 19 and can rotate around the seventh guide rod 19 as an axis.

[0020] The first rope winch 27-1 and the first fixed pulley 7 and the second fixed pulley 11 in the first flexible permanent magnet variable stiffness mechanism are circumscribed on the same straight line, and the second rope winch 27-1 and the first fixed pulley 7 and the second fixed pulley 11 in the second flexible permanent magnet variable stiffness mechanism are circumscribed on the same straight line.

[0021] The movable pulley 12 in the flexible permanent magnet variable stiffness mechanism is clamped on the symmetry axis of the fixed pulley 7 and the fixed pulley 11 .

[0022] The first rope 6-1 and the second rope 6-2 are soft steel wire ropes or ropes made of other soft materials that can only bend but cannot axially expand and contract.

[0023] A deep groove ball bearing, a coupling 28 and a reducer 29 are arranged in sequence along the rotation axis of the rope winch 27. One end of the rotating shaft of the rope winch is connected to the output end of the coupling 28 through a deep groove ball bearing, the input end of the coupling 28 is connected to the output end of the reducer 29, and the other end of the rotating shaft of the rope winch is in contact with the boom housing 1 outside the boom carrier 2 to fix its position.

[0024] The input end of the reducer 29 is provided with a coupling 22 and a servo motor 23 in sequence along the axis, and the input end of the reducer 29 is connected to the servo motor 23 through the coupling 22 .

[0025] The servo motor 23 is provided with an encoder 24 . The servo motor 23 is fixedly connected to a servo motor fixing seat 25 . The reducer 29 is fixedly connected to a reducer fixing seat 26 .

[0026] The servo motor fixing seat 25, the reducer fixing seat 26 and the permanent magnet variable stiffness mechanism fixing seat 8 are all fixedly connected to the upper arm carrier 2, the upper arm carrier 2 and the joint carrier 3 are fixedly connected, the joint carrier 3 is fixedly connected to the first joint displacement guide block 30, and the forearm is fixedly connected to the second joint displacement guide block 21.

[0027] Advantages and effects:

[0028] In recent years, with the rapid development of permanent magnetic material research, there have been major technological breakthroughs in the research of rare earth permanent magnetic materials with high magnetic energy per unit volume, so that original elastic elements such as springs are gradually replaced by permanent magnets. Compared with the original elastic elements, the magnetic force generated between permanent magnets has the advantages of low noise, low friction coefficient, smooth response and long life.

[0029] The present invention proposes a permanent magnet variable stiffness joint adopting a dual magnetic pulley group control structure, which comprises: (i) two groups of drive units, each group of drive units comprises: a servo motor, an encoder, a bevel gear reducer, a coupling 1, a coupling 2, a motor fixing seat, a reducer fixing seat, a deep groove ball bearing, and a cable winch; (ii) two groups of variable stiffness elements, each group of variable stiffness units comprises: a fixed pulley 1, a fixed pulley 2, a pulley, an axially magnetized conical permanent magnetic ring 1, an axially magnetized conical permanent magnetic ring 2, a movable slide seat, a movable slide groove, an axial sliding bearing, a fixed seat, and a fixed washer; (iii) an elbow joint motion unit comprises: a guide shaft, a fixed support, a guide body, a pulley group 1, a pulley group 2, a guide wheel, a joint bearing body, an arm carrier, a joint positioning block, a joint fixing block, a rope fixing groove, a joint displacement guide block, and an arm shell.

[0030] The rope winch is a winch shaft in which the winch and the rotating shaft are integrated. Deep groove ball bearings, couplings, bevel gear reducers, couplings, and servo motors are arranged in sequence along the rotating axis of the rope winch. The servo motor and reducer are fixed to the base through a fixing sleeve, and the rope winch is fixed through the upper structure of the arm housing. The rope winch is connected to the reducer through a coupling.

[0031] The movable slide is slidably matched with the movable slide groove, the axial sliding bearing is located at the symmetric center of the crossbeam of the fixed seat, the sliding rod of the movable slide is slidably matched with the sliding bearing, the movable pulley is located at the end of the sliding rod of the movable slide, and the two fixed pulleys are located at the upper end of the fixed seat with the slide groove. The movable pulley and the two fixed pulleys form an isosceles triangle, and the rope is pulled to drive the movable pulley and the movable slide to slide upward;

[0032] The fixed seat is fixed with the conical permanent magnetic ring 1, and the movable slide is fixed with the conical permanent magnetic ring 2. The conical permanent magnetic ring 1 and the conical permanent magnetic ring 2 are arranged coaxially, and the structural parameters of the conical permanent magnetic ring 1 and the conical permanent magnetic ring 2 are the same. The conical permanent magnetic ring 1 and the conical permanent magnetic ring 2 are axially magnetized, and the same-direction magnetic poles are arranged relative to each other. When the movable slide and the fixed seat slide relative to each other, the air gap between the conical permanent magnetic ring 1 and the conical permanent magnetic ring 2 is reduced. The two variable stiffness joints are fixed to the arm carrier on the opposite surfaces through the parts fixed seat.

[0033] The arm carrier is fixed to the joint carrier, the guide shaft is perpendicular to the joint guide part 1, the support part and the positioning part, and is fixed to the two, and the joint guide part and the positioning part are fixed to the joint carrier by bolts. The joint guide part 1 and the joint guide part 2 are tangent.

[0034] Compared with the prior art, the present invention has the following advantages:

[0035] 1. A new variable stiffness joint is designed, which has the following advantages over the existing variable stiffness joint: it can generate a larger joint torque through a smaller motor input and increase the rotation range of the joint. In this design, the permanent magnet variable stiffness mechanism is optimized and improved, and a conical annular permanent magnet ring is selected to replace the horizontal permanent magnet ring, which has the advantage of a larger relative working cross-sectional area of ​​the magnet. In the design of the fixed seat, combined with the actual installation considerations of the joint, the fixed seat is designed as an inclined structure with the same taper as the conical permanent magnet ring. Since the placement position of the pulley block in the variable stiffness module is an isosceles triangle with variable height, the conical design of the fixed seat has the characteristics of saving space, making the assembly structure more compact.

[0036] 2. This design uses a magnetic pulley structure, and the joint position changes depending on the different tension positions of the two pulley groups. The pulley group at the joint applies quaternion theory, and the servo motor input torque can increase the output exponentially. The joint rotation is always tangent to two circular arcs with fixed radius, so the distance between the two center points remains unchanged. The advantage of this design is that the lines in the forearm joint can be safely arranged inside it without being affected by the joint movement.

[0037] 3. The present invention can place the drive unit and the variable stiffness joint at the rear in specific use. Since the parallel structure is used in the design, when constructing a multi-degree-of-freedom joint, the disadvantage of the serial structure, which is insufficient in the ability to change stiffness due to the superposition of inertia of multiple degrees of freedom, is optimized. In addition, a dual-structure control is designed, which greatly improves the timeliness of the joint control ability. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A schematic diagram of the structure of a flexible robot arm of the present invention;

[0039] Figure 2 is a cross-sectional schematic diagram of a variable stiffness unit;

[0040] Figure 3 It is a partial structural diagram of the elbow joint pulley assembly;

[0041] Figure 4 This is an exploded view of the driving structure of the rope winch;

[0042] Figure 5 It is a three-dimensional schematic diagram of a first conical axially magnetized permanent magnetic ring and a second conical axially magnetized permanent magnetic ring;

[0043] Figure 6 A three-dimensional schematic diagram showing a rope fixing groove;

[0044] Figure 7 A schematic diagram showing the structure of the guide wheels within the elbow joint carrier.

[0045] In the figure, 1 is the upper arm housing, 2 is the upper arm carrier, 3 is the elbow joint carrier, 4 is the lower arm housing, 5 is the pulley block, 6 is the rope, 7 is the first fixed pulley, 8 is the fixed seat, 9 is the axial sliding bearing, 10 is the fixed washer, 11 is the second fixed pulley, 12 is the pulley, 13 is the first conical axial magnetized permanent magnet ring, 14 is the second conical axial magnetized permanent magnet ring, 15 is the movable slide, 16 is the movable slide, 17 is the joint positioning block, 18 is the joint fixing block, 19 is the guide rod, 20 is the rope fixing groove, 21 is the joint displacement guide block, 22 is the coupling 1, 23 is the private service motor, 24 is the encoder, 25 is the private service motor fixing seat, 26 is the reducer fixing seat, 27 is the rope winch, 28 is the coupling 2, 29 is the reducer. DETAILED DESCRIPTION

[0046] The present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. This allows the present invention to fully understand and implement how to use technical means to solve technical problems and achieve the technical process of meeting the requirements. It should be noted that as long as there is no conflict, the various embodiments of the present invention and the various features in each embodiment can be used in conjunction with each other, and the technical solutions formed are all within the protection scope of the present invention.

[0047] A flexible permanent magnet variable stiffness robot joint, characterized in that it comprises a boom carrier 2, an elbow joint carrier 3, a forearm, a pulley block 5 and a rope winch, the boom carrier 2 is connected to the elbow joint carrier 3 and the forearm, the elbow joint carrier 3 is connected to the forearm through the pulley block 5 (that is, the pulley block 5 is arranged between the elbow joint carrier 3 and the forearm), and the rope winch 27 is arranged on the boom carrier 2; a flexible permanent magnet variable stiffness mechanism is arranged on the boom carrier 2;

[0048] There are two rope winches, namely a first rope winch 27-1 and a second rope winch 27-2 (such as Figure 1 As shown), the flexible permanent magnet variable stiffness mechanism is two (as shown Figure 1 One of them can be seen in the figure, and the other one cannot be shown in the following figure), which are respectively the first flexible permanent magnet variable stiffness mechanism and the second flexible permanent magnet variable stiffness mechanism;

[0049] The flexible permanent magnet variable stiffness mechanism comprises a fixed seat 8 and a movable slide seat 16;

[0050] The fixed seat 8 includes two vertical plates 8-1 and a connecting plate 8-2 connecting the two vertical plates 8-1. The movable slide seat 16 is a "↓"-shaped structure composed of a sliding rod 16-2 and a conical base 16-1 (like Figure 2 As shown, it is similar to an arrow pointing downward, and the so-called conical base 16-1 is as shown in FIG. Figure 2 The shape shown can also be called V-shaped, and the corresponding connecting plate 8-2 is also V-shaped), the lower end of the sliding rod 16-2 is provided with a conical base 16-1, the upper end of the sliding rod 16-2 passes through the connecting plate 8-2 and can move up and down relative to the connecting plate 8-2 (that is, move along the axial direction of the sliding rod 16-2, that is, as shown in FIG. Figure 2 up and down movement as shown),

[0051] A pulley 12 is disposed at the upper end of the sliding rod 16-2, and the pulley 12 is connected to the sliding rod 16-2 and can move axially with the sliding rod 16-2. Relative to the first fixed pulley 7 and the second fixed pulley 11, the pulley 12 can be equivalent to the function of a movable pulley. A fixed pulley is disposed at the top of each of the two vertical plates 8-1, namely the first fixed pulley 7 and the second fixed pulley 11;

[0052] A first conical permanent magnet ring 13 is provided at the bottom of the connecting plate 8-2 (the first conical permanent magnet ring is magnetized along the outer normal direction of the conical inclined surface, and the outer conical inclined surface is an N pole, such as Figure 2 As shown), a second conical permanent magnet ring 14 corresponding to the first conical permanent magnet ring 13 is provided at the upper end of the conical base 16-1 (the second conical permanent magnet ring is magnetized along the inner normal direction of the conical inclined surface, and the inner conical inclined surface surface is an N pole, as shown in FIG. Figure 2 (shown)

[0053] The rope wound on the first rope winch 27-1 passes through the upper end of the first fixed pulley 7, the lower end of the pulley 12 and the upper end of the second fixed pulley 11 in the first flexible permanent magnet variable stiffness mechanism in sequence (such as Figure 2 As shown) is connected to the pulley block 5;

[0054] The rope wound on the second rope winch 27 - 2 is connected to the pulley block 5 after passing through the upper end of the first fixed pulley 7 , the lower end of the pulley 12 and the upper end of the second fixed pulley 11 in the second flexible permanent magnet variable stiffness mechanism in sequence.

[0055] The inner sides of the two vertical plates 8-1 are provided with movable slide grooves 15 ( Figure 2 The left and right ends of the conical base 16-1 extend into the movable slide groove 15 or are arranged on the movable slide rail and can move up and down along the movable slide groove 15 or the movable slide rail (that is, move axially along the sliding rod 16-2, that is, as shown in the dashed line in the middle) or the movable slide rail, the left and right ends of the conical base 16-1 extend into the movable slide groove 15 or are arranged on the movable slide rail and can move up and down along the movable slide groove 15 or the movable slide rail (that is, move axially along the sliding rod 16-2, that is, as shown in the middle dashed line) or the movable slide rail, Figure 2 As shown in the figure, the movable slide 15 and the movable slide rail are selected.

[0056] The pulley block 5 includes a first joint displacement guide block 30 and a second joint displacement guide block 21. The arc edge A of the first joint displacement guide block 30 contacts the arc edge B of the second joint displacement guide block 21 (i.e., Figure 3 As shown, the first joint displacement guide block 30 and the second joint displacement guide block 21 are both fan-shaped structures with arc-shaped surfaces), so that the arc-shaped edge B of the second joint displacement guide block 21 can roll on the arc-shaped edge A of the first joint displacement guide block 30;

[0057] The first guide rod 19-1, the second guide rod 19-2, the fourth guide rod 19-4 and the sixth guide rod 19-6 are vertically arranged on the side of the first joint displacement guide block 30; (that is, the first guide rod 19-1, the second guide rod 19-2, the fourth guide rod 19-4 and the sixth guide rod 19-6 are perpendicular to the first joint displacement guide block 30, such as Figure 3 As shown in FIG. 1 , the first guide rod 19-1, the second guide rod 19-2 and the fourth guide rod 19-4 are arranged in a three-point arrangement (i.e., the axis connecting the first guide rod 19-1, the second guide rod 19-2 and the fourth guide rod 19-4 forms a triangle, as shown in FIG. Figure 3 As shown in the figure, the sixth guide rod 19-6 is located at the arc center position of the arc along A of the first joint displacement guide block 30, and the third guide rod 19-3, the fifth guide rod 20 and the seventh guide rod 19 are vertically arranged on the side of the second joint displacement guide block 21; the axes of the third guide rod 19-3, the fifth guide rod 20 and the seventh guide rod 19 are located on the same straight line or the third guide rod 19-3, the fifth guide rod 20 and the seventh guide rod 19 are arranged in a three-point manner (that is, the axes of the third guide rod 19-3, the fifth guide rod 20 and the seventh guide rod 19 are arranged in a three-point manner). The seventh guide rod 19 is located at the arc center of the arc B of the second joint displacement guide block 21; the first rope 6-1 led out from the upper end of the second fixed pulley 11 in the first flexible permanent magnet variable stiffness mechanism is passed around the upper end of the first guide rod 19-1, then passed around the lower end of the second guide rod 19-2, and then passed around the lower end of the third guide rod 19-3, and then repeatedly wound between the second guide rod 19-2 and the third guide rod 19-3, and finally the first rope 6-1 is fixed on the second guide rod 19-2 or the third guide rod 19-3;

[0058] (The first rope 6-1 and the second rope 6-2 are collectively referred to as rope 6, that is, Figure 2 Number 6 in the

[0059] The second rope 6-2 led out from the upper end of the second fixed pulley 11 in the second flexible permanent magnet variable stiffness mechanism passes through the lower end of the first guide rod 19-1, then passes through the upper end of the fourth guide rod 19-4, and then passes through the fifth guide rod 20, and then repeatedly wraps around the fourth guide rod 19-4 and the fifth guide rod 20, and finally is fixed on the fourth guide rod 19-4 or the fifth guide rod 20;

[0060] The rear end of the joint positioning block 17 is sleeved on the sixth guide rod 19 - 6 and can rotate around the sixth guide rod 19 - 6 as an axis, and the front end of the joint positioning block 17 is sleeved on the seventh guide rod 19 and can rotate around the seventh guide rod 19 as an axis.

[0061] The first rope winch 27-1 and the first fixed pulley 7 and the second fixed pulley 11 in the first flexible permanent magnet variable stiffness mechanism are circumscribed on the same straight line, and the second rope winch 27-1 and the first fixed pulley 7 and the second fixed pulley 11 in the second flexible permanent magnet variable stiffness mechanism are circumscribed on the same straight line.

[0062] The movable pulley 12 in the flexible permanent magnet variable stiffness mechanism is clamped on the symmetry axis of the fixed pulley 7 and the fixed pulley 11 .

[0063] The first rope 6-1 and the second rope 6-2 are soft steel wire ropes or ropes made of other soft materials that can only bend but cannot axially expand and contract.

[0064] The rope winch is an integral structure in which the rope winch and the rotating shaft are integrated. Deep groove ball bearings, couplings 28 and reducers 29 are arranged in sequence along the rotating axis of the rope winch 27 (the first rope winch 27-1 and the second rope winch 27-2 are collectively referred to as the rope winch 27). One end of the rotating shaft of the rope winch is connected to the output end of the coupling 28 through a deep groove ball bearing, and the input end of the coupling 28 is connected to the output end of the reducer 29. The other end of the rotating shaft of the rope winch is in contact with the boom housing 1 outside the boom carrier 2, and its position is fixed (here, the so-called fixing of the rotating shaft means that it can only realize the function of rotation, but cannot translate in the radial and axial directions, that is, the rotating shaft of the rope winch is in contact with the boom housing 1, which serves as a support to enable the rope winch to rotate stably).

[0065] The input end of the reducer 29 is provided with a coupling 22 and a servo motor 23 in sequence along the axis, and the input end of the reducer 29 is connected to the servo motor 23 through the coupling 22 .

[0066] The servo motor 23 is provided with an encoder 24 . The servo motor 23 is fixedly connected to a servo motor fixing seat 25 . The reducer 29 is fixedly connected to a reducer fixing seat 26 .

[0067] The servo motor fixing seat 25, the reducer fixing seat 26 and the permanent magnet variable stiffness mechanism fixing seat 8 are all fixedly connected to the upper arm carrier 2, the upper arm carrier 2 and the joint carrier 3 are fixedly connected, the joint carrier 3 is fixedly connected to the first joint displacement guide block 30, and the forearm is fixedly connected to the joint fixing block (18) and the second joint displacement guide block 21 (by bolts). (A joint fixing block (18) is respectively arranged at the position corresponding to the first joint displacement guide block 30 and the second joint displacement guide block 21, the joint fixing block (18-A) corresponding to the first joint displacement guide block 30 is connected to the joint carrier 3, and the joint fixing block (18-B) corresponding to the second joint displacement guide block 21 is connected to the forearm, and the first guide rod 19-1, the second guide rod 19-2, the fourth guide rod 19-4 and the sixth guide rod 19-6 are located between the first joint displacement guide block 30 and the joint fixing block (18-A);

[0068] The third guide rod 19-3, the fifth guide rod 20 and the seventh guide rod 19 are located between the second joint displacement guide block 21 and the joint fixing block (18-B)

[0069] The movable slide seat 16 is slidably matched with the fixed seat 8, the sliding rod of the movable slide seat 16 is slidably matched with the sliding bearing (9), and the sliding bearing (9) is located on the axial symmetric center line of the axial sliding bearing fixed seat 8;

[0070] The movable pulley 12, the first fixed pulley 7 and the second fixed pulley 11 are arranged in an isosceles triangle (that is, the axis connecting the movable pulley 12, the first fixed pulley 7 and the second fixed pulley 11 is an isosceles triangle);

[0071] The fixed seat 8 is fixed to the first conical axial magnetized permanent magnet ring 13, and the second conical axial magnetized permanent magnet ring 14 is fixedly placed between the movable slide seat 16 and fixedly fixed. The first conical permanent magnet ring 13 is coaxially arranged with the central axis of the second conical permanent magnet ring 14, and the taper and upper and lower circle radii of the first conical permanent magnet ring 13 and the second conical permanent magnet ring 14 are the same (i.e. Figure 5 As shown, the upper circle radius of the first conical permanent magnet ring 13 is the same as the upper circle radius of the second conical permanent magnet ring 14, and the lower circle radius of the first conical permanent magnet ring 13 is the same as the lower circle radius of the second conical permanent magnet ring 14), and the first conical permanent magnet ring 13 and the second conical permanent magnet ring 14 are arranged opposite to each other with the same magnetic poles (as shown in FIG. Figure 2 As shown in FIG. 1 , when the distance between the movable slide 16 and the connecting plate 8 - 2 is reduced, the air gap between the magnetic rings of the first conical permanent magnet ring 13 and the second conical permanent magnet ring 14 is reduced.

[0072] The movable pulley 12 is located at the upper end of the sliding rod of the movable slide 16, and the first fixed pulley 7 and the second fixed pulley 11 are located at the upper end of the vertical plate 8-1 of the fixed seat 8.

[0073] By pulling the rope 6, the movable pulley 12 and the movable slide 16 are driven to slide upward, and the pulley block 5 includes a rope fixing groove 31 (the rope fixing groove needs to be designed according to the actual situation. Here, it is just to prevent the rope from contacting parts 30, 18-A and 18-B. The first guide rod 19-1, the second guide rod 19-2, the third guide rod 19-3, the fourth guide rod 19-4 and the fifth guide rod 20 are all provided with rope fixing grooves (31) to prevent the rope from being strangled) to ensure that the position of the rope 6 is fixed.

[0074] The motor-controlled joint of the present invention has two sets of components with the same configuration, so the following implementation scheme represents the implementation methods of two sets of controlled joints.

[0075] Combination Figure 1 , Figure 2 , Figure 4This embodiment is described. This embodiment includes: a rope winch 27, a first fixed pulley 7, a pulley 12, a second fixed pulley 11, an elbow joint carrier 3, a guide rod, and a pulley block 5. One end of the rope 6 is fixed on the rope winch 27, and passes through the first fixed pulley 7, the movable pulley 12, the second fixed pulley 11, the guide wheel (32-1) inside the elbow joint carrier 3 in sequence (the guide wheel (32-1) also contains two. It acts on the two ropes 6-1 and 6-2 respectively, and mainly plays a guiding transition role), the pulley block 5, and the other end of the rope 6 is fixed on the pulley block. The rope winch 27, the first fixed pulley 7, and the second fixed pulley 11 are circumscribed on the same straight line, and the pulley 12 is clamped on the symmetry axis of the fixed pulley 7 and the fixed pulley 11. The pulley block 5 includes a rope fixing groove 20 to ensure that the position of the rope 6 is fixed.

[0076] The rope 6 in the present invention is a soft steel wire rope or other soft rope made of materials that can only bend but cannot axially expand and contract.

[0077] The present invention is a permanent magnet variable stiffness flexible robot driving joint with simple movement form, simple manufacturing and simple operation.

[0078] Furthermore, in the present embodiment, the rope winch 27 is a winch shaft in which the rope winch and the rotating shaft are integrated. Deep groove ball bearings, the output end of the coupling 28, and the reducer 29 are arranged in sequence along the rotating axis of the rope winch 27. The other end of the rotating shaft of the rope winch 27 is in contact with the boom housing 1 and fixed in position, so that the rotating shaft of the rope winch 27 can rotate with the rope winch 27 and cannot move in the axial and radial directions. The input end of the reducer 28 has a coupling 22 and a servo motor 23 in sequence along the axis. By pulling the rope 6, the pulley 12 and the movable slide 16 are driven to slide upward. The servo motor 23 is provided with an encoder 24 and is fixedly connected to the servo motor fixing seat 25. The reducer 29 is fixedly connected to the reducer fixing seat 26. The servo motor fixing seat 25, the reducer fixing seat 26, and the permanent magnet variable stiffness mechanism fixing seat 8 are all fixedly connected to the upper arm carrier 2, the upper arm carrier 2 and the joint carrier 3 are fixedly connected, and the joint carrier 3 is respectively fixedly connected to the joint fixing block 18 and the joint displacement guide block 30.

[0079] Further, in this embodiment, the movable slide 16 is slidably matched with the fixed seat 8, the axial sliding bearing is on the axial symmetry center of the fixed seat 8, the sliding rod of the movable slide 16 is slidably matched with the sliding bearing 9, the pulley 12 is located at the end of the sliding rod of the movable slide 16, the first fixed pulley 7 and the second fixed pulley 11 are located at the upper end of the fixed seat 8, and the pulley 12 and the first fixed pulley 7 and the second fixed pulley 11 are arranged in an isosceles triangle;

[0080] Further, the fixed seat 8 is consolidated with the first conical axial magnetized permanent magnet ring 13, a fixed washer 10 is placed between the second conical axial magnetized permanent magnet ring 14 and the movable slide 16 (to prevent the lower magnetic ring from shaking and to adjust the spacing height) and consolidated therewith, the first conical axial magnetized permanent magnet ring 13 and the second conical axial magnetized permanent magnet ring 14 are coaxially arranged with the central axis, the first conical axial magnetized permanent magnet ring 13 and the second conical axial magnetized permanent magnet ring 14 have the same structural parameters, and when the 8-2 spacing between the movable slide 16 and the fixed seat 8 is reduced, the air gap between the magnetic rings is reduced;

[0081] The conical permanent magnet ring in the present invention is axially magnetized, and the first conical axially magnetized permanent magnet ring 13 and the second conical axially magnetized permanent magnet ring 14 are arranged opposite to each other with the same magnetic poles;

[0082] The specific use process of this application is: when you need to lift your forearm upward, Figure 1 In the state described above, at this time, the first rope winch 27-1 gradually loosens the first rope 6-1. At this time, under the mutual repulsion of the first conical axially magnetized permanent magnet ring 13 and the second conical axially magnetized permanent magnet ring 14, the conical base 16-1 in the first flexible permanent magnet variable stiffness mechanism gradually moves downward, and the first rope 6-1 leaves enough margin for the second guide rod 19-2 and the third guide rod 19-3 to separate from each other. At the same time, the second rope winch 27-2 gradually contracts the second rope 6-2. At this time, the conical base 16-1 in the second flexible permanent magnet variable stiffness mechanism gradually moves toward The connecting plate 8-2 moves, and the mutual repulsion between the first conical axially magnetized permanent magnet ring 13 and the second conical axially magnetized permanent magnet ring 14 generates a flexible buffer force. At the same time, as the second rope 6-2 is gradually tightened, the fourth guide rod 19-4 and the fifth guide rod 20 move closer to each other, and the second guide rod 19-2 and the third guide rod 19-3 separate from each other, so that the second joint displacement guide block 21 passes through the arc surface B and rolls along the arc edge A of the first joint displacement guide block 30. Because the second joint displacement guide block 21 is connected to the forearm, it drives the forearm to lift.

[0083] When the forearm needs to be lowered, the first rope winch 27-1 gradually loosens the first rope 6-1 and gradually tightens the first rope 6-1, so that the second guide rod 19-2 and the third guide rod 19-3 move closer to each other, while the fourth guide rod 19-4 and the fifth guide rod 20 move away from each other, completing the lowering action of the forearm.

Claims

1. A variable stiffness joint of a magnetic pulley robot, characterized in that: The invention comprises a boom carrier (2), an elbow joint carrier (3), a forearm, a pulley block (5) and a rope winch, wherein the boom carrier (2) is connected to the forearm via the elbow joint carrier (3), the elbow joint carrier (3) is connected to the forearm via the pulley block (5), and the rope winch (27) is arranged on the boom carrier (2); a flexible permanent magnet variable stiffness mechanism is arranged on the boom carrier (2); There are two rope winches, namely a first rope winch (27-1) and a second rope winch (27-2); there are two flexible permanent magnet variable stiffness mechanisms, namely a first flexible permanent magnet variable stiffness mechanism and a second flexible permanent magnet variable stiffness mechanism; The flexible permanent magnet variable stiffness mechanism comprises a fixed seat (8) and a movable slide seat (16); The fixed seat (8) comprises two vertical plates (8-1) and a connecting plate (8-2) connecting the two vertical plates (8-1); the movable sliding seat (16) is a "↓"-shaped structure composed of a sliding rod (16-2) and a conical base (16-1); the conical base (16-1) is arranged at the lower end of the sliding rod (16-2); the upper end of the sliding rod (16-2) passes through the connecting plate (8-2) and can move up and down relative to the connecting plate (8-2); A pulley (12) is disposed at the upper end of the sliding rod (16-2), and a fixed pulley is disposed at the top ends of the two vertical plates (8-1), namely, a first fixed pulley (7) and a second fixed pulley (11); A first conical permanent magnetic ring (13) is arranged at the bottom of the connecting plate (8-2), and a second conical permanent magnetic ring (14) corresponding to the first conical permanent magnetic ring (13) is arranged at the upper end of the conical base (16-1); The rope wound around the first rope winch (27-1) is connected to the pulley block (5) after passing through the upper end of the first fixed pulley (7), the lower end of the pulley (12) and the upper end of the second fixed pulley (11) in the first flexible permanent magnet variable stiffness mechanism in sequence; The rope wound around the second rope winch (27-2) is connected to the pulley block (5) after passing through the upper end of the first fixed pulley (7), the lower end of the pulley (12) and the upper end of the second fixed pulley (11) in the second flexible permanent magnet variable stiffness mechanism in sequence; A movable slide groove (15) or a movable slide rail is arranged on the inner side of the two vertical plates (8-1), and the left and right ends of the conical base (16-1) extend into the movable slide groove (15) or are arranged on the movable slide rail and can move up and down along the movable slide groove (15) or the movable slide rail; The pulley block (5) comprises a first joint displacement guide block (30) and a second joint displacement guide block (21), wherein an arcuate edge (A) of the first joint displacement guide block (30) contacts an arcuate edge (B) of the second joint displacement guide block (21), so that the arcuate edge (B) of the second joint displacement guide block (21) can roll on the arcuate edge (A) of the first joint displacement guide block (30); A first guide rod (19-1), a second guide rod (19-2), a fourth guide rod (19-4) and a sixth guide rod (19-6) are vertically arranged on the side of the first joint displacement guide block (30); the first guide rod (19-1), the second guide rod (19-2) and the fourth guide rod (19-4) are arranged in a three-point arrangement, the sixth guide rod (19-6) is located at the arc center position of the arc edge (A) of the first joint displacement guide block (30), and a third guide rod (19-3), a fifth guide rod (20) and a seventh guide rod (19) are vertically arranged on the side of the second joint displacement guide block (21); the axes of the third guide rod (19-3), the fifth guide rod (20) and the seventh guide rod (19) are located at the same The third guide rod (19-3), the fifth guide rod (20) and the seventh guide rod (19) are arranged in a three-point manner on a straight line, and the seventh guide rod (19) is located at the arc center of the arc edge (B) of the second joint displacement guide block (21); the first rope (6-1) led out from the upper end of the second fixed pulley (11) in the first flexible permanent magnet variable stiffness mechanism is passed around the upper end of the first guide rod (19-1), then passed around the lower end of the second guide rod (19-2), then passed around the lower end of the third guide rod (19-3), and then repeatedly passed between the second guide rod (19-2) and the third guide rod (19-3); finally, the first rope (6-1) is fixed to the second guide rod (19-2) or the third guide rod (19-3); A second rope (6-2) led out from the upper end of the second fixed pulley (11) in the second flexible permanent magnet variable stiffness mechanism passes around the lower end of the first guide rod (19-1), then passes around the upper end of the fourth guide rod (19-4), then passes around the fifth guide rod (20), then repeatedly wraps around the fourth guide rod (19-4) and the fifth guide rod (20), and finally is fixed to the fourth guide rod (19-4) or the fifth guide rod (20); The rear end of the joint positioning block (17) is sleeved on the sixth guide rod (19-6) and can rotate around the sixth guide rod (19-6) as an axis, and the front end of the joint positioning block (17) is sleeved on the seventh guide rod (19) and can rotate around the seventh guide rod (19) as an axis.

2. A variable stiffness joint of a magnetic pulley robot according to claim 1, characterized in that: The first rope winch (27-1) and the first fixed pulley (7) and the second fixed pulley (11) in the first flexible permanent magnet variable stiffness mechanism are circumscribed on the same straight line, and the second rope winch (27-1) and the first fixed pulley (7) and the second fixed pulley (11) in the second flexible permanent magnet variable stiffness mechanism are circumscribed on the same straight line.

3. The variable stiffness joint of a magnetic pulley robot according to claim 1, characterized in that: The movable pulley (12) in the flexible permanent magnet variable stiffness mechanism is clamped on the symmetry axis of the fixed pulley (7) and the fixed pulley (11).

4. The variable stiffness joint of a magnetic pulley robot according to claim 1, characterized in that: The first rope (6-1) and the second rope (6-2) are soft steel wire ropes or ropes made of other soft materials that can only bend but cannot axially stretch.

5. The variable stiffness joint of a magnetic pulley robot according to claim 1, characterized in that: A deep groove ball bearing, a coupling (28) and a reducer (29) are arranged in sequence along the rotation axis of the rope winch (27); one end of the rotation axis of the rope winch is connected to the output end of the coupling (28) via the deep groove ball bearing; the input end of the coupling (28) is connected to the output end of the reducer (29); the other end of the rotation axis of the rope winch is in contact with a boom housing (1) outside a boom carrier (2) to fix its position.

6. The variable stiffness joint of a magnetic pulley robot according to claim 5, characterized in that: The input end of the reducer (29) is provided with a coupling (22) and a servo motor (23) in sequence along the axis, and the input end of the reducer (29) is connected to the servo motor (23) via the coupling (22).

7. The variable stiffness joint of a magnetic pulley robot according to claim 6, characterized in that: The servo motor (23) is provided with an encoder (24), the servo motor (23) is fixedly connected to a servo motor fixing seat (25), and the reducer (29) is fixedly connected to a reducer fixing seat (26).

8. The variable stiffness joint of a magnetic pulley robot according to claim 7, characterized in that: The servo motor fixing seat (25), the reducer fixing seat (26) and the permanent magnet variable stiffness mechanism fixing seat (8) are all fixedly connected to the upper arm carrier (2), the upper arm carrier (2) and the elbow joint carrier (3) are fixedly connected, the elbow joint carrier (3) is fixedly connected to the first joint displacement guide block (30), and the lower arm is fixedly connected to the second joint displacement guide block (21).

Images