Two-degree-of-freedom series elastic drive lower limb rehabilitation instrument

Abstract

The invention relates to a two-degree-of-freedom series elastic drive lower limb rehabilitation apparatus which comprises a left lower limb rehabilitation assembly and a right lower limb rehabilitation assembly which are arranged side by side, and each of the left lower limb rehabilitation assembly and the right lower limb rehabilitation assembly comprises a supporting base and a leg fixing mechanism. The linear series elastic element driving mechanism and the rotary series elastic element driving mechanism are used for driving the knee joints and the ankle joints to bend and stretch respectively, and the airwave pressure air bags are worn on the legs. According to the technical scheme, the rotary series elastic element driving mechanism drives the foot pedal to rotate through gear transmission, and the linear series elastic element driving mechanism drives the leg fixing mechanism to integrally move through a ball screw, so that rehabilitation training of the ankle joint and the knee joint is achieved, and reliable safety is achieved; the rehabilitation time of the patient can be effectively shortened, and the rehabilitation training efficiency of the patient is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of rehabilitation equipment, and in particular to a two-degree-of-freedom series elastically driven lower limb rehabilitation equipment. Background Art

[0002] The lower limbs play a vital role in the daily life of the human body. However, factors such as age or disease may lead to limited or even complete loss of lower limb movement, seriously affecting people's daily life. In recent years, with the improvement of living standards, the demand for lower limb rehabilitation training for people with limited or lost mobility has increased. Due to the large population of my country, the number of rehabilitation physicians cannot meet the growing demand. Therefore, various institutions have begun to research and develop equipment and institutions that can assist or even replace physicians in lower limb rehabilitation training.

[0003] At present, existing lower limb rehabilitation training equipment usually adopts a single training mode. For example, some equipment is purely active and is mainly suitable for mild patients who can actively train. However, for severely disabled patients, these equipment are difficult to achieve effective rehabilitation training. On the contrary, some equipment is purely passive. Although it can be used for rehabilitation training of severely disabled patients, it is completely dependent on the drive of the equipment, which will greatly affect the patient's rehabilitation efficiency in the later stage of rehabilitation.

[0004] At the same time, the design of traditional rehabilitation equipment focuses on achieving functional requirements. They usually adopt a rigid structure mechanical design, which will cause the output end of the rehabilitation equipment to be too rigid. Under such working conditions, the high rigidity of traditional rehabilitation equipment will bring serious safety hazards to the rehabilitation treatment process of human-machine interaction with patients.

[0005] Therefore, there is an urgent need to study a human lower limb rehabilitation device to better solve the problems of the existing technology, such as lack of active and passive fusion mode, lack of safety, and impact on rehabilitation effect. Summary of the invention

[0006] The purpose of the present invention is to overcome the above-mentioned drawbacks and provide a two-degree-of-freedom series elastically driven lower limb rehabilitation device, which can realize active and passive rehabilitation of patients, enhance the safety of rehabilitation training, and improve the rehabilitation efficiency of patients.

[0007] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: comprising a left lower limb rehabilitation component and a right lower limb rehabilitation component arranged in parallel, the left lower limb rehabilitation component and the right lower limb rehabilitation component have the same structure, and each comprises a support base and a leg fixing mechanism, the leg fixing mechanism comprises a thigh fixing bracket, a calf fixing bracket and a foot pedal connected in sequence, one end of the thigh fixing bracket is rotatably connected to the support base, the other end of the thigh fixing bracket is rotatably connected to one end of the calf fixing bracket to form a knee joint, and the other end of the calf fixing bracket is rotatably connected to the foot pedal to form an ankle joint; a bracket connecting the calf fixing bracket and the support base is provided between the calf fixing bracket and the support base, the top of the bracket is rotatably connected to the calf fixing bracket, and the bottom of the bracket is slidably connected to the support base; It also includes a linear series elastic element driving mechanism and a rotary series elastic element driving mechanism for driving the knee joint and the ankle joint to achieve flexion and extension respectively, and an air wave pressure airbag worn on the leg; The linear series elastic element driving mechanism includes a ball screw and a moving rod arranged in parallel, and also includes a moving seat sleeved on the ball screw and the moving rod, the moving seat is connected in sequence by a front plate, a left plate, a rear plate and a right plate to form a frame-shaped whole, and a moving plate is also provided between the front plate and the rear plate, wherein: the front plate and the rear plate are respectively sleeved on the ball screw through a screw sleeve, and the inner diameter of the screw sleeve is larger than the major diameter of the ball screw thread; the moving plate is connected to the ball screw through a screw nut, and the front plate and the moving plate, and the moving plate and the rear plate are connected. The ball screws between the plates are respectively sleeved with first springs, and the two ends of the first springs are respectively abutted against the adjacent plate surfaces, and the moving rods between the front plate and the moving plate and between the moving plate and the rear plate are respectively sleeved with second springs, and the two ends of the second springs are respectively abutted against the adjacent plate surfaces, and the two ends of the ball screw are respectively fixed to the support base through a screw support seat, one end of the moving rod is fixedly connected to the rear plate, and the other end of the moving rod passes through the moving plate and the front plate and is rotatably connected to the bracket through a fourth pin shaft, and the connection is detachable, and the moving rod is slidably matched with the front plate and the moving plate; The rotary series elastic element driving mechanism includes a motor module, an outer shell fixed to the output disk of the motor module, and an end cover fixed to the outer shell, a disc is concentrically arranged in the outer shell, and the disc is connected to the inner wall of the outer shell through a fourth spring; it also includes a transmission module, the transmission module includes an output shaft, a driving bevel gear, an input shaft and a driven bevel gear, one end of the output shaft is fixedly connected to the center of the disc through a flat key, the other end of the output shaft passes through the end cover and is fixedly connected to the driving bevel gear through a flat key, one end of the input shaft is fixedly connected to the second fixed seat on the foot pedal through a flat key, the other end of the input shaft passes through the third fixed seat on the foot pedal and is fixedly connected to the driven bevel gear through a flat key, the driving bevel gear is meshed with the driven bevel gear, and the output shaft and the end cover, and the input shaft and the third fixed seat are respectively connected through deep groove ball bearings.

[0008] A screw bearing is provided between the ball screw and the screw support seat, the ball screw is driven by a servo motor, the servo motor is fixed to the support base through a motor bracket, and the output shaft of the servo motor is connected to one end of the ball screw through a coupling; The linear series elastic element driving mechanism also includes an optical axis that passes through the front plate, the movable plate and the rear plate. The two ends of the optical axis are respectively connected and fixed to the screw support seat through the shaft end covers. The optical axis is slidably matched with the front plate, the movable plate and the rear plate. A third spring is respectively mounted on the optical axis between the front plate and the movable plate and between the movable plate and the rear plate, and the two ends of the third spring are respectively abutted against the adjacent plate surfaces.

[0009] A grating ruler assembly is also provided on the support base, the setting direction of the grating ruler assembly is consistent with the axial direction of the ball screw, and the grating head in the grating ruler assembly is fixedly connected to the left side plate of the moving seat through a connecting bracket.

[0010] A cross-shaped boss is provided at the center of the disk surface on one side of the disk close to the end cover, and the boss includes a columnar through hole at the center and a first spring seat evenly distributed along the circumference of the columnar through hole; the outer shell is evenly distributed with a second spring seat along the circumference of its inner wall, the second spring seat corresponds to the position of the first spring seat, and the first spring seat and the second spring seat corresponding to each other are connected by a fourth spring, and the first spring seat and the second spring seat are respectively provided with four groups; The motor module is connected to the outer side of the calf fixing bracket through a module fixing bracket.

[0011] The foot pedal includes a pedal body and a strap fixed on the pedal body for easy wearing of the foot. The pedal body is provided with a first fixing seat on the board surface close to the ankle joint side. The first fixing seat is arranged perpendicular to the board surface. The calf fixing bracket is rotatably connected to the first fixing seat through a first pin shaft.

[0012] The thigh fixing bracket comprises thigh connecting rod fixing rails symmetrically arranged on both sides of the supporting base in the left-right direction, the bottoms of the two sets of thigh connecting rod fixing rails are connected into one body through an arc-shaped thigh supporting plate, and the tops of the two sets of thigh connecting rod fixing rails are provided with thigh straps connecting the two sets; the two sets of thigh connecting rod fixing rails are respectively provided with thigh connecting rods with adjustable lengths; The thigh connecting rod comprises a first connecting rod rotatably connected to the support base via a second pin shaft and a second connecting rod rotatably connected to the calf fixing bracket, the end of the first connecting rod hinged to the support base is bent, the first connecting rod and the second connecting rod are respectively provided with screw fixing holes with equal spacing, and the first connecting rod and the second connecting rod are fixed to the thigh connecting rod fixing rail by screws; The second connecting rod is rotatably connected to the third connecting rod on the calf fixing bracket through a connecting transition piece. The connecting transition piece includes a sleeve and a connecting ear seat. The sleeve is arranged on the end of the second connecting rod and fixed by a screw. The connecting ear seat is rotatably connected to the calf fixing bracket through a third pin shaft to form a knee joint.

[0013] The calf fixing bracket comprises calf connecting rod fixing rails symmetrically arranged along the left and right directions, the bottoms of two sets of calf connecting rod fixing rails are connected into one body through an arc-shaped calf supporting plate, and the tops of the two sets of calf connecting rod fixing rails are provided with calf straps connecting the two sets; and the two sets of calf connecting rod fixing rails are respectively provided with calf connecting rods with adjustable lengths; The calf connecting rod includes a third connecting rod rotatably connected to the connecting transition piece through a third pin shaft and a fourth connecting rod rotatably connected to the first fixing seat on the foot pedal through a first pin shaft. The end of the third connecting rod hinged to the connecting transition piece is disc-shaped. The third connecting rod and the fourth connecting rod are respectively provided with screw fixing holes with equal spacing. The third connecting rod and the fourth connecting rod are fixed to the calf connecting rod fixing rail by screws.

[0014] The cross-section of the thigh connecting rod fixing rail is C-shaped, including an upper wing plate, a lower wing plate and a web plate. The upper wing plate and the lower wing plate are respectively provided with a first convex strip and a second convex strip on the adjacent plate surfaces. The top and bottom surfaces of the first connecting rod are respectively provided with a first groove matching the first convex strip. The top and bottom surfaces of the second connecting rod are respectively provided with a second groove matching the second convex strip. The first connecting rod and the second connecting rod are fixed to the web plate by screws, and the web plate is provided with fixing holes with equal spacing.

[0015] The bracket includes a fifth connecting rod arranged in parallel in the left and right directions. The two fifth connecting rods are connected as a whole through a sixth connecting rod. The top ends of the fifth connecting rods are rotatably connected to the first fixed seats on the foot pedals. The bottoms of the fifth connecting rods are respectively provided with sliders, and the sliders are slidably connected to the slide rails arranged on the support base.

[0016] A frame body is arranged above the left lower limb rehabilitation component and the right lower limb rehabilitation component. A left gravity suspension foot restraint mechanism A matched with the left lower limb rehabilitation component and a right gravity suspension foot restraint mechanism B matched with the right lower limb rehabilitation component are arranged in the frame body. The left gravity suspension foot restraint mechanism A and the right gravity suspension foot restraint mechanism B have the same structure and respectively include a hook, a foot restraint device, a weight and a flexible rope. The foot restraint device includes a foot restraint strap worn on the calf and a lifting ring connected to the two ends of the foot restraint strap. One end of the flexible rope is fixed to the weight, and the other end of the flexible rope is fixedly connected to the cover body of the hook after winding through the guide wheel and the traction rotating pulley group on the frame body in sequence. The hook body of the hook is connected to the lifting ring. The flexible rope, guide wheel, traction rotating pulley group and weight are all arranged in two groups, the guide wheel is respectively fixed on the upright column of the frame body, and the traction rotating pulley group is respectively fixed on the two corresponding top beams of the frame body.

[0017] It can be seen from the above technical solution that the rotary series elastic element driving mechanism of the present invention drives the foot pedal to rotate through gear transmission, and the linear series elastic element driving mechanism drives the overall movement of the leg fixing mechanism through a ball screw, thereby realizing the rehabilitation training of the ankle joint and the knee joint. During the training, the air wave pressure airbag wraps the lower limbs and exerts a squeezing effect on the lower limbs. At the same time, the present invention can adjust the corresponding active and passive rehabilitation training modes according to the patient's rehabilitation situation, and can also adjust the length of the leg fixing mechanism according to the user's leg size. The present invention has reliable safety and good adaptability, can effectively shorten the patient's rehabilitation time, and improve the patient's rehabilitation training efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a three-dimensional structural schematic diagram of the present invention.

[0019] Figure 2 It is a schematic diagram of the three-dimensional structure of the left lower limb rehabilitation component of the present invention.

[0020] Figure 3 It is a three-dimensional structural schematic diagram of the leg fixing mechanism of the present invention.

[0021] Figure 4 It is a partial structural diagram of the thigh connecting rod fixing rail of the present invention.

[0022] Figure 5 It is a schematic diagram of the exploded structure of the leg fixing mechanism of the present invention.

[0023] Figure 6 It is a structural schematic diagram of the thigh connecting rod of the present invention.

[0024] Figure 7 It is a structural schematic diagram of a foot pedal of the present invention.

[0025] Figure 8 It is a structural schematic diagram of the base, grating assembly and bracket of the present invention.

[0026] Fig. 9 It is a schematic diagram of the overall structure of the linear series elastic element driving mechanism of the present invention.

[0027] Fig.10 It is a schematic diagram of the exploded structure of the linear series elastic element driving mechanism of the present invention.

[0028] Fig.11 It is a structural schematic diagram of the traction rotating pulley block of the present invention.

[0029] Fig.12 It is a structural schematic diagram of the hook of the present invention.

[0030] Fig.13 It is a schematic diagram of the overall structure of the rotary series elastic element driving mechanism of the present invention.

[0031] Fig.14 It is a structural schematic diagram of the disc of the present invention.

[0032] Fig.15 It is a schematic diagram of the exploded structure of the rotary series elastic element driving mechanism of the present invention.

[0033] Fig.16 It is a structural schematic diagram of the gravity suspension foot restraining mechanism of the present invention.

[0034] Fig.17 It is a schematic diagram of three positions during rehabilitation training of the present invention.

[0035] The symbols in the above drawings are: support base 1, thigh fixing bracket 2, thigh connecting rod fixing rail 21, upper wing plate 211, lower wing plate 212, belly plate 213, first convex strip 214, second convex strip 215, thigh supporting plate 22, thigh strap 23, first connecting rod 24, first groove 241, second connecting rod 25, second groove 251, connecting transition piece 26, ferrule 261, connecting ear seat 262, air wave pressure airbag 27, calf fixing bracket 3, calf connecting rod fixing Rail 31, calf support plate 32, calf strap 33, third connecting rod 34, fourth connecting rod 35, foot pedal 4, first fixing seat 41, second fixing seat 42, third fixing seat 43, pedal body 44, strap 45, linear series elastic element driving mechanism 5, ball screw 51, first spring 511, screw support seat 512, screw bearing 513, moving rod 52, second spring 521, moving seat 53, front plate 531, left side plate 532, rear plate 533 , right side plate 534, moving plate 54, lead screw sleeve 55, lead screw nut 56, servo motor 57, motor bracket 571, coupling 572, optical axis 58, third spring 581, shaft end cover 582, rotary series elastic element driving mechanism 6, motor module 61, module fixing bracket 611, outer shell 62, second spring seat 621, disc 63, boss 631, columnar through hole 6311, first spring seat 6312, fourth spring 64, output shaft 65, main Moving bevel gear 66, input shaft 67, driven bevel gear 68, end cover 69, grating scale assembly 7, connecting bracket 71, bracket 8, fifth connecting rod 81, sixth connecting rod 82, slide rail 83, slider 84, left gravity suspension foot restraining mechanism 9A, right gravity suspension foot restraining mechanism 9B, hook 91, cover body 911, hook body 912, foot restraining device 92, foot restraining belt 921, lifting ring 922, weight 93, flexible rope 94, guide wheel 95, traction rotating pulley group 96, frame body 10. DETAILED DESCRIPTION

[0036] The present invention will be further described below in conjunction with the accompanying drawings: like Figure 1 , Figure 2The two-degree-of-freedom series elastic drive lower limb rehabilitation device shown in the figure includes a left lower limb rehabilitation component and a right lower limb rehabilitation component arranged in parallel. The left lower limb rehabilitation component and the right lower limb rehabilitation component have the same structure and each includes a support base 1 and a leg fixing mechanism. The leg fixing mechanism includes a thigh fixing bracket 2, a calf fixing bracket 3 and a foot pedal 4 connected in sequence. One end of the thigh fixing bracket 2 is rotatably connected to the support base 1, and the other end of the thigh fixing bracket 2 is rotatably connected to one end of the calf fixing bracket 3 to form a knee joint. The other end of the calf fixing bracket 3 is rotatably connected to the foot pedal 4 to form an ankle joint. It also includes a linear series elastic element driving mechanism 5 and a rotary series elastic element driving mechanism 6 that respectively drive the knee joint and the ankle joint to achieve flexion and extension, and an air wave pressure airbag 27 worn on the leg. The air wave pressure airbag 27 can achieve leg recovery by orderly and repeatedly inflating and deflating each chamber. The specific structure of the air wave pressure airbag 27 can refer to the prior art.

[0037] Further, such as Fig. 9 , Fig.10 As shown, the linear series elastic element driving mechanism 5 includes a ball screw 51 and a moving rod 52 arranged in parallel. The ball screw 51 is arranged along the length direction of the support base 1, that is, consistent with the length direction of the human body's legs. The two ends of the ball screw 51 are fixed to the support base 1 through a screw support seat 512, and a screw bearing 513 is arranged between the ball screw 51 and the screw support seat 512. The ball screw 51 is driven by a servo motor 57, and the servo motor 57 is fixed to the support base 1 through a motor bracket 571. The output shaft of the servo motor 57 is connected to one end of the ball screw 51 through a coupling 572.

[0038] The linear series elastic element driving mechanism 5 also includes a moving seat 53 sleeved on the ball screw 51 and the moving rod 52. The moving seat 53 is connected in sequence by a front plate 531, a left plate 532, a rear plate 533 and a right plate 534 to form a frame-shaped whole. A moving plate 54 is also provided between the front plate 531 and the rear plate 533, wherein: the front plate 531 and the rear plate 533 are sleeved on the ball screw 51 through a screw sleeve 55 respectively, and the inner diameter of the screw sleeve 55 is larger than the major diameter of the thread of the ball screw 51, and the moving plate 54 is connected to the ball screw 51 through a screw nut 56. One end of the moving rod 52 is fixedly connected to the rear plate 533, and the other end of the moving rod 52 passes through the moving plate 54 and the front plate 531 and is rotatably connected to the bracket 8 through a fourth pin shaft, and the connection is detachable, and the moving rod 52 is slidably matched with the front plate 531 and the moving plate 54.

[0039] The linear series elastic element driving mechanism 5 also includes an optical axis 58 that penetrates the front plate 531, the movable plate 54 and the rear plate 533. The two ends of the optical axis 58 are respectively connected and fixed to the screw support seat 512 through the shaft end cover 582, and the optical axis 58 is slidably matched with the front plate 531, the movable plate 54 and the rear plate 533.

[0040] A first spring 511 is sleeved on the ball screw 51 between the front plate 531 and the moving plate 54 and between the moving plate 54 and the rear plate 533, respectively, and the two ends of the first spring 511 are respectively against the adjacent plate surface. A second spring 521 is sleeved on the moving rod 52 between the front plate 531 and the moving plate 54 and between the moving plate 54 and the rear plate 533, respectively, and the two ends of the second spring 521 are respectively against the adjacent plate surface. A third spring 581 is sleeved on the optical axis 58 between the front plate 531 and the moving plate 54 and between the moving plate 54 and the rear plate 533, respectively, and the two ends of the third spring 581 are respectively against the adjacent plate surface.

[0041] In this embodiment, the front plate 531, the rear plate 533 and the movable plate 54 are in a "convex" shape as a whole. The movable plate 54 is an independent plate and has no fixed relationship with the movable seat 53. The front plate 531, the rear plate 533 and the movable plate 54 are respectively provided with through holes that match the ball screw 51, the movable rod 52 and the optical axis 58, wherein: the movable plate 54 is fixed with a screw nut 56 at the through hole that matches the ball screw 51, and the movable plate 54 forms a screw nut movement with the ball screw 51 through the screw nut 56, and the front plate 531 and the rear plate 533 are fixed with a screw sleeve 55 at the through hole that matches the ball screw 51, and the inner wall of the screw sleeve 55 is a smooth surface, which can slide smoothly on the ball screw 51. One end of the movable rod 52 is interference fit with the through hole on the rear plate 533, and the through holes on the front plate 531 and the movable plate 54 form a sliding fit with the movable rod 52. The optical axis 58 is slidably matched with the through holes on the front plate 531 , the rear plate 533 and the movable plate 54 .

[0042] Further, such as Figure 8 As shown, a grating ruler assembly 7 is also provided on the support base 1, and the setting direction of the grating ruler assembly 7 coincides with the axial direction of the ball screw 51. The grating head in the grating ruler assembly 7 is fixedly connected to the left side plate 532 of the moving seat 53 through the connecting bracket 71. The grating ruler assembly 7 measures the position of the moving rod 52 in the linear series elastic element driving mechanism 5, and provides high-precision and reliable position information to achieve high-precision movement of the knee joint.

[0043] Further, such as Fig.13 , Fig.14 , Fig.15As shown, the rotary series elastic element driving mechanism 6 includes a motor module 61, an outer shell 62 fixed to the output disk of the motor module 61, and an end cover 69 fixed to the outer shell 62. The motor module 61 is connected to the outer side of the calf fixing bracket 3 through a module fixing bracket 611. A disc 63 is concentrically arranged in the outer shell 62, and the disc 63 is connected to the inner wall of the outer shell 62 through a fourth spring 64. Specifically, a cross-shaped boss 631 is provided at the center of the disk surface of the disk 63 on one side close to the end cover 69, and the boss 631 includes a columnar through hole 6311 at the center and a first spring seat 6312 uniformly distributed along the circumference of the columnar through hole 6311; the outer shell 62 is uniformly distributed with second spring seats 621 along the circumference of its inner wall, and the second spring seats 621 correspond to the positions of the first spring seats 6312, and the corresponding first spring seats 6312 and the second spring seats 621 are connected by a fourth spring 64, and four groups of first spring seats 6312 and second spring seats 621 are respectively provided.

[0044] The rotary series elastic element driving mechanism 6 also includes a transmission module, which includes an output shaft 65, a driving bevel gear 66, an input shaft 67 and a driven bevel gear 68. One end of the output shaft 65 is fixedly connected to the center of the disk 63 through a flat key, and the other end of the output shaft 65 passes through the end cover 69 and is fixedly connected to the driving bevel gear 66 through a flat key. One end of the input shaft 67 is fixedly connected to the second fixed seat 42 on the foot pedal 4 through a flat key, and the other end of the input shaft 67 passes through the third fixed seat 43 on the foot pedal 4 and is fixedly connected to the driven bevel gear 68 through a flat key. The driving bevel gear 66 is meshed with the driven bevel gear 68, and the output shaft 65 and the end cover 69, and the input shaft 67 and the third fixed seat 43 are respectively connected through deep groove ball bearings.

[0045] Further, such as Figure 3 , Figure 5 As shown, the thigh fixing bracket 2 includes thigh connecting rod fixing rails 21 symmetrically arranged on both sides of the supporting base 1 along the left-right direction, the bottoms of the two sets of thigh connecting rod fixing rails 21 are connected into one by an arc-shaped thigh supporting plate 22, and the tops of the two sets of thigh connecting rod fixing rails 21 are provided with thigh straps 23 connecting the two; the two sets of thigh connecting rod fixing rails 21 are respectively provided with thigh connecting rods with adjustable lengths.

[0046] In this embodiment, the thigh connecting rod includes a first connecting rod 24 rotatably connected to the support base 1 through a second pin shaft and a second connecting rod 25 rotatably connected to the calf fixing bracket 3. The end of the first connecting rod 24 hinged to the support base 1 is bent, and the second connecting rod 25 is rotatably connected to the third connecting rod on the calf fixing bracket 3 through a connecting transition piece 26. The connecting transition piece 26 includes a ferrule 261 and a connecting ear seat 262. The ferrule 261 is sleeved on the end of the second connecting rod 25 and fixed by screws. The connecting ear seat 262 is rotatably connected to the calf fixing bracket 3 through the third pin shaft to form a knee joint. The first connecting rod 24 and the second connecting rod 25 are respectively provided with screw fixing holes with equal spacing, and the first connecting rod 24 and the second connecting rod 25 are fixed to the thigh connecting rod fixing rail 21 by screws.

[0047] Furthermore, if Figure 4 , Figure 6 As shown, the cross-section of the thigh link fixing rail 21 is C-shaped, including an upper wing plate 211, a lower wing plate 212 and a web 213. The upper wing plate 211 and the lower wing plate 212 are respectively provided with a first convex strip 214 and a second convex strip 215 on the plate surfaces close to each other. The top and bottom surfaces of the first connecting rod 24 are respectively provided with a first groove 241 matching with the first convex strip 214, and the top and bottom surfaces of the second connecting rod 25 are respectively provided with a second groove 251 matching with the second convex strip 215. The first connecting rod 24 and the second connecting rod 25 are fixed to the web 213 by screws, and the web 213 is provided with fixing holes with equal spacing.

[0048] Further, such as Figure 3 As shown, the calf fixing bracket 3 includes calf connecting rod fixing rails 31 symmetrically arranged along the left-right direction, the bottoms of the two groups of calf connecting rod fixing rails 31 are connected into one body through an arc-shaped calf supporting plate 32, and the tops of the two groups of calf connecting rod fixing rails 31 are provided with calf straps 33 connecting the two; the two groups of calf connecting rod fixing rails 31 are respectively provided with calf connecting rods with adjustable lengths.

[0049] In this embodiment, the calf link includes a third link 34 rotatably connected to the connecting transition piece 26 via a third pin and a fourth link 35 rotatably connected to the first fixing seat 41 on the foot pedal 4 via a first pin. The end of the third link 34 hinged to the connecting transition piece 26 is disc-shaped. The third link 34 and the fourth link 35 are respectively provided with screw fixing holes with equal spacing. The third link 34 and the fourth link 35 are fixed to the calf link fixing rail 31 via screws. The calf link fixing rail 31 in this embodiment has the same structure as the thigh link fixing rail 21, which will not be repeated here.

[0050] Further, such as Figure 7As shown, the foot pedal 4 includes a pedal body 44 and a strap 45 fixed on the pedal body 44 for easy wearing of the foot. The pedal body 44 is provided with a first fixing seat 41 on the board surface near the ankle joint side. The first fixing seat 41 is arranged perpendicular to the board surface, and the calf fixing bracket 3 is rotatably connected to the first fixing seat 41 through a first pin. In this embodiment, the first fixing seat 41 is connected to the fourth connecting rod 35 in the calf fixing bracket 3 and the fifth connecting rod 81 in the bracket 8 through a first pin. The second fixing seat 42 and the third fixing seat 43 on the foot pedal 4 are both arranged parallel to the first fixing seat 41.

[0051] Further, such as Figure 8 As shown, a bracket 8 is provided between the calf fixing bracket 3 and the support base 1 to connect the two, the top of the bracket 8 is rotatably connected to the calf fixing bracket 3, and the bottom of the bracket 8 is slidably connected to the support base 1. Specifically, the bracket 8 includes a fifth connecting rod 81 arranged in parallel in the left and right directions, and the two fifth connecting rods 81 are connected as a whole through a sixth connecting rod 82, the top of the fifth connecting rod 81 is respectively rotatably connected to the first fixing seat 41 on the foot pedal 4, and the bottom of the fifth connecting rod 81 is respectively provided with a slider 84, and the slider 84 is slidably connected to the slide rail 83 arranged on the support base 1.

[0052] Further, such as Fig.16 As shown, a frame body 10 is arranged above the left lower limb rehabilitation component and the right lower limb rehabilitation component, and a left gravity suspension foot restraint mechanism 9A matched with the left lower limb rehabilitation component and a right gravity suspension foot restraint mechanism 9B matched with the right lower limb rehabilitation component are arranged in the frame body 10. The left gravity suspension foot restraint mechanism 9A and the right gravity suspension foot restraint mechanism 9B have the same structure, and each includes a hook 91, a foot restraint device 92, a weight 93 and a flexible rope 94. The foot restraint device 92 includes a foot restraint belt 921 worn on the calf and a ring 922 connected to the two ends of the foot restraint belt 921. One end of the flexible rope 94 is fixed to the weight 93, and the other end of the flexible rope 94 is fixedly connected to the cover body 911 of the hook 91 after passing through the guide wheel 95 and the traction rotating pulley group 96 on the frame body 10 in turn. The hook body 912 of the hook 91 is connected to the ring 922. Fig.11 , Fig.12 In this embodiment, two groups of flexible ropes 94, guide wheels 95, traction rotating pulley groups 96, and weights 93 are provided, the guide wheels 95 are respectively fixed on the columns of the frame body 10, and the traction rotating pulley groups 96 are respectively fixed on the two corresponding top beams of the frame body 10. The structure of the traction rotating pulley group 96 can refer to the prior art.

[0053] The purpose of setting the left gravity suspension foot restraint mechanism 9A and the right gravity suspension foot restraint mechanism 9B is to achieve the lifting force of the gravity suspension foot restraint mechanism on the legs of patients with different weights by adaptively adjusting the mass of the weight 93. During active rehabilitation training, the gravity suspension foot restraint mechanism reduces the load of knee flexion and extension by lifting the legs, which is beneficial to knee rehabilitation; during passive rehabilitation training, the gravity suspension foot restraint mechanism reduces the load of the motor by lifting the legs to protect the motor. The working principle of the present invention is as follows: 1. The working principle of the linear series elastic element driving mechanism 5 is: like Fig.17 As shown, when the servo motor 57 rotates forward, the ball screw 51 is driven to rotate through the coupling 572, and the screw nut 56 on the ball screw 51 drives the moving plate 54 to move forward. The forward movement of the moving plate 54 will synchronously squeeze the first spring 511, the second spring 521 and the third spring 581 between the moving plate 54 and the front plate 531, thereby pushing the entire moving seat 53 forward, driving the moving rod 52 to move forward synchronously, and the moving rod 52 pushes the bracket 8 to move forward along the direction defined by the slide rail 83 on the support base 1, thereby allowing the knee joint to perform an extension movement; conversely, the servo motor 57 is reversed, the moving plate 54 moves backward, synchronously squeezing the first spring 511, the second spring 521 and the third spring 581 between the moving plate 54 and the rear plate 533, driving the moving seat 53 to move backward, and at this time the knee joint performs a flexion movement.

[0054] 2. The working principle of the rotary series elastic element driving mechanism 6 is: When the motor module 61 is working, the output disk of the motor module 61 will drive the outer shell 62 to rotate synchronously, and the outer shell 62 will drive the disk 63 to rotate through the fourth spring 64, so that the driving bevel gear 66 will rotate, and the driven bevel gear 68 meshing with the driving bevel gear 66 will drive the foot pedal 4 to rotate. The clockwise rotation of the foot pedal 4 forms the flexion movement of the ankle joint, and vice versa, it forms the extension movement of the ankle joint.

[0055] The working process of the present invention is as follows: When the present invention is used for the first time, it is necessary to adjust the connection positions of the corresponding connecting rods in the thigh fixing bracket and the calf fixing bracket according to the patient's leg size; after the adjustment is completed, the patient puts on the air wave pressure airbag, then passes through the foot strap, and fixes the legs with the thigh strap and the calf strap.

[0056] When the patient needs passive rehabilitation, a certain mass of weight is placed according to the patient's adaptability. The weight only needs to make the ankle straps feel lifted when connected to the lower limbs, so as to reduce the burden on the motor. At this time, the servo motor of the linear series elastic element drive mechanism works, driving the moving rod to move, and realizing the flexion and extension of the knee joint. At the same time, the motor module of the rotary series elastic element drive mechanism works, driving the foot pedal to rotate through a pair of bevel gears, and realizing the flexion and extension of the ankle joint.

[0057] When the patient needs active rehabilitation, the connection between the movable rod and the bracket is first disassembled, and then a certain mass of weights is placed according to the patient's adaptability. The weights must enable the patient's lower limbs to be significantly lifted. At this time, the patient's lower limbs are connected to the ankle straps, and the knee joint can be actively flexed and extended with the assistance of the weights. Then the patient can overcome the weight of the weights to achieve extension of the knee joint.

[0058] 1. The present invention provides two lower limb rehabilitation training exercises including knee flexion and extension and ankle flexion and extension, and joint training exercises and air wave pressure therapy are performed simultaneously, which shortens the rehabilitation training time to a certain extent and reduces the rehabilitation cost.

[0059] 2. The present invention adopts a rotary series elastic element driving mechanism to achieve ankle flexion and extension, and a linear series elastic element driving mechanism to achieve knee flexion and extension. This enables the series elastic element to absorb and alleviate uncertain forces and impacts from lower limb rehabilitation training, thereby providing better safety and comfort. At the same time, the series elastic element can adapt to load changes and environmental disturbances, providing more flexible and reliable execution capabilities.

[0060] 3. The present invention provides two lower limb rehabilitation training modes, active and passive, which overcomes the shortcomings of traditional lower limb rehabilitation devices that only provide passive or active training. Patients adopt passive rehabilitation training in the early stage of rehabilitation and active rehabilitation training in the late stage of rehabilitation. This rehabilitation strategy can effectively shorten the patient's rehabilitation time and improve the patient's rehabilitation training efficiency.

[0061] 4. The lengths of the thigh fixing bracket and the calf fixing bracket of the present invention are adjustable, which is conducive to adjusting the component sizes of the device according to different user needs.

[0062] 5. The present invention uses a grating ruler to measure the position of the moving rod in the linear series elastic element driving mechanism, which can achieve high-precision movement of the knee joint.

[0063] The embodiments described above are merely descriptions of preferred implementations of the present invention and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A two-degree-of-freedom series elastic drive lower limb rehabilitation device, characterized in that: The invention comprises a left lower limb rehabilitation component and a right lower limb rehabilitation component which are arranged in parallel. The left lower limb rehabilitation component and the right lower limb rehabilitation component have the same structure and respectively comprise a support base (1) and a leg fixing mechanism. The leg fixing mechanism comprises a thigh fixing bracket (2), a calf fixing bracket (3) and a foot pedal (4) which are connected in sequence. One end of the thigh fixing bracket (2) is rotatably connected to the support base (1), the other end of the thigh fixing bracket (2) is rotatably connected to one end of the calf fixing bracket (3) to form a knee joint, and the other end of the calf fixing bracket (3) is rotatably connected to the foot pedal (4) to form an ankle joint. A bracket (8) is provided between the calf fixing bracket (3) and the support base (1) to connect the two. The top of the bracket (8) is rotatably connected to the calf fixing bracket (3), and the bottom of the bracket (8) is slidably connected to the support base (1). It also includes a linear series elastic element driving mechanism (5) and a rotary series elastic element driving mechanism (6) for driving the knee joint and the ankle joint to achieve flexion and extension respectively, and an air wave pressure airbag (27) worn on the leg; The linear series elastic element driving mechanism (5) comprises a ball screw (51) and a moving rod (52) arranged in parallel, and also comprises a moving seat (53) sleeved on the ball screw (51) and the moving rod (52), wherein the moving seat (53) is formed by a front plate (531), a left plate (532), a rear plate (533) and a right plate (534) connected in sequence to form a frame-shaped whole, and a moving plate (54) is further provided between the front plate (531) and the rear plate (533), wherein: the front plate (531) and the rear plate (533) are respectively sleeved on the ball screw (51) through a screw sleeve (55), and the inner diameter of the screw sleeve (55) is larger than the major diameter of the thread of the ball screw (51); the moving plate (54) is connected to the ball screw (51) through a screw nut (56), and between the front plate (531) and the moving plate (54), the moving plate (54) A first spring (511) is sleeved on the ball screw (51) between the front plate (531) and the movable plate (54) and the rear plate (533), and two ends of the first spring (511) are respectively abutted against the adjacent plate surface; a second spring (521) is sleeved on the movable rod (52) between the front plate (531) and the movable plate (54) and between the movable plate (54) and the rear plate (533), and two ends of the second spring (521) are respectively abutted against the adjacent plate surface; two ends of the ball screw (51) are respectively fixed to the support base (1) through a screw support seat (512); one end of the movable rod (52) is fixedly connected to the rear plate (533); the other end of the movable rod (52) passes through the movable plate (54) and the front plate (531), and is rotatably connected to the bracket (8) through a fourth pin shaft, and the connection is detachable; the movable rod (52) is slidably matched with the front plate (531) and the movable plate (54); The rotary series elastic element drive mechanism (6) comprises a motor module (61), an outer shell (62) fixed to an output disk of the motor module (61), and an end cover (69) fixed to the outer shell (62); a disk (63) is coaxially arranged inside the outer shell (62); the disk (63) is connected to the inner wall of the outer shell (62) via a fourth spring (64); and a transmission module is also included, the transmission module comprising an output shaft (65), a driving bevel gear (66), an input shaft (67) and a driven bevel gear (68); one end of the output shaft (65) is fixedly connected to the center of the disk (63) via a flat key. The other end of the output shaft (65) passes through the end cover (69) and is fixedly connected to the driving bevel gear (66) by a flat key. One end of the input shaft (67) is fixedly connected to the second fixing seat (42) on the foot pedal (4) by a flat key. The other end of the input shaft (67) passes through the third fixing seat (43) on the foot pedal (4) and is fixedly connected to the driven bevel gear (68) by a flat key. The driving bevel gear (66) is meshed with the driven bevel gear (68). The output shaft (65) and the end cover (69) and the input shaft (67) and the third fixing seat (43) are respectively connected by deep groove ball bearings.

2. The two-degree-of-freedom series elastic drive lower limb rehabilitation device according to claim 1, characterized in that: A screw bearing (513) is provided between the ball screw (51) and the screw support seat (512); the ball screw (51) is driven by a servo motor (57); the servo motor (57) is fixed to the support base (1) via a motor bracket (571); and the output shaft of the servo motor (57) is connected to one end of the ball screw (51) via a coupling (572); The linear series elastic element driving mechanism (5) further comprises an optical axis (58) penetrating the front plate (531), the movable plate (54) and the rear plate (533); two ends of the optical axis (58) are respectively connected and fixed to the lead screw support seat (512) via shaft end covers (582); the optical axis (58) is slidably matched with the front plate (531), the movable plate (54) and the rear plate (533); a third spring (581) is respectively sleeved on the optical axis (58) between the front plate (531) and the movable plate (54) and between the movable plate (54) and the rear plate (533); and two ends of the third spring (581) are respectively in contact with adjacent plate surfaces.

3. The two-degree-of-freedom series elastic drive lower limb rehabilitation device according to claim 1, characterized in that: The support base (1) is also provided with a grating ruler assembly (7), the setting direction of the grating ruler assembly (7) coincides with the axial direction of the ball screw (51), and the grating head in the grating ruler assembly (7) is fixedly connected to the left side plate (532) of the movable seat (53) via a connecting bracket (71).

4. The two-degree-of-freedom series elastic drive lower limb rehabilitation device according to claim 1, characterized in that: A cross-shaped boss (631) is provided at the center of the disk surface on one side of the disk (63) close to the end cover (69), and the boss (631) includes a columnar through hole (6311) at the center and first spring seats (6312) uniformly distributed along the circumference of the columnar through hole (6311); the outer shell (62) is uniformly distributed along the circumference of its inner wall with second spring seats (621), the second spring seats (621) correspond to the positions of the first spring seats (6312), and the first spring seats (6312) and the second spring seats (621) corresponding to each other are connected via a fourth spring (64), and four groups of the first spring seats (6312) and the second spring seats (621) are provided respectively; The motor module (61) is connected to the outer side of the calf fixing bracket (3) via a module fixing bracket (611).

5. The two-degree-of-freedom series elastic drive lower limb rehabilitation device according to claim 1, characterized in that: The foot pedal (4) comprises a pedal body (44) and a strap (45) fixed to the pedal body (44) for easy wearing of the foot. The pedal body (44) is provided with a first fixing seat (41) on the board surface close to the ankle joint side. The first fixing seat (41) is arranged perpendicular to the board surface. The calf fixing bracket (3) is rotatably connected to the first fixing seat (41) via a first pin shaft.

6. The two-degree-of-freedom series elastic drive lower limb rehabilitation device according to claim 1, characterized in that: The thigh fixing bracket (2) comprises thigh connecting rod fixing rails (21) symmetrically arranged on both sides of the supporting base (1) in the left-right direction, the bottoms of the two sets of thigh connecting rod fixing rails (21) are connected into one body through an arc-shaped thigh supporting plate (22), and the tops of the two sets of thigh connecting rod fixing rails (21) are provided with thigh straps (23) connecting the two sets; and the two sets of thigh connecting rod fixing rails (21) are respectively provided with thigh connecting rods with adjustable lengths; The thigh connecting rod comprises a first connecting rod (24) rotatably connected to the support base (1) via a second pin shaft, and a second connecting rod (25) rotatably connected to the calf fixing bracket (3), the end of the first connecting rod (24) hinged to the support base (1) is bent, the first connecting rod (24) and the second connecting rod (25) are respectively provided with screw fixing holes with equal spacing, and the first connecting rod (24) and the second connecting rod (25) are fixed to the thigh connecting rod fixing rail (21) via screws; The second connecting rod (25) is rotatably connected to the third connecting rod on the calf fixing bracket (3) via a connecting transition piece (26); the connecting transition piece (26) comprises a clamping sleeve (261) and a connecting ear seat (262); the clamping sleeve (261) is sleeved on the end of the second connecting rod (25) and fixed by a screw; the connecting ear seat (262) is rotatably connected to the calf fixing bracket (3) via a third pin shaft to form a knee joint.

7. The two-degree-of-freedom series elastic drive lower limb rehabilitation device according to claim 1, characterized in that: The calf fixing bracket (3) comprises calf connecting rod fixing rails (31) symmetrically arranged in the left-right direction, the bottoms of the two sets of calf connecting rod fixing rails (31) are connected into one body via an arc-shaped calf supporting plate (32), and the tops of the two sets of calf connecting rod fixing rails (31) are provided with calf straps (33) connecting the two sets; and the two sets of calf connecting rod fixing rails (31) are respectively provided with calf connecting rods with adjustable lengths; The calf connecting rod comprises a third connecting rod (34) rotatably connected to the connecting transition piece (26) via a third pin shaft, and a fourth connecting rod (35) rotatably connected to the first fixing seat (41) on the foot pedal (4) via a first pin shaft, the end of the third connecting rod (34) hinged to the connecting transition piece (26) is disc-shaped, and the third connecting rod (34) and the fourth connecting rod (35) are respectively provided with screw fixing holes with equal spacing, and the third connecting rod (34) and the fourth connecting rod (35) are fixed to the calf connecting rod fixing rail (31) via screws.

8. The two-degree-of-freedom series elastic drive lower limb rehabilitation device according to claim 6, characterized in that: The thigh connecting rod fixing rail (21) has a C-shaped cross section and comprises an upper wing plate (211), a lower wing plate (212) and a web plate (213). The upper wing plate (211) and the lower wing plate (212) are provided with a first convex strip (214) and a second convex strip (215) on the adjacent plate surfaces. The top and bottom surfaces of the first connecting rod (24) are provided with a first groove (241) matching with the first convex strip (214). The top and bottom surfaces of the second connecting rod (25) are provided with a second groove (251) matching with the second convex strip (215). The first connecting rod (24) and the second connecting rod (25) are fixed to the web plate (213) by screws. The web plate (213) is provided with fixing holes with equal spacing.

9. The two-degree-of-freedom series elastic drive lower limb rehabilitation device according to claim 1, characterized in that: The bracket (8) comprises a fifth connecting rod (81) arranged in parallel in the left-right direction, the two fifth connecting rods (81) are connected to each other via a sixth connecting rod (82), the top ends of the fifth connecting rods (81) are rotatably connected to the first fixing seats (41) on the foot pedal (4), and the bottom ends of the fifth connecting rods (81) are provided with sliding blocks (84), and the sliding blocks (84) are slidably connected to the sliding rails (83) provided on the support base (1).

10. The two-degree-of-freedom series elastic drive lower limb rehabilitation device according to claim 1, characterized in that: A frame body (10) is arranged above the left lower limb rehabilitation component and the right lower limb rehabilitation component. A left gravity suspension foot restraint mechanism (9A) matched with the left lower limb rehabilitation component and a right gravity suspension foot restraint mechanism (9B) matched with the right lower limb rehabilitation component are arranged inside the frame body (10). The left gravity suspension foot restraint mechanism (9A) and the right gravity suspension foot restraint mechanism (9B) have the same structure and respectively comprise a hook (91), a foot restraint device (92), a weight (93) and a flexible rope (94). The foot restraint device (92) comprises a foot restraint strap (921) worn on the calf and a lifting ring connected to the two ends of the foot restraint strap (921). (922), one end of the flexible rope (94) is fixed to the weight (93), the other end of the flexible rope (94) is successively wound around the guide wheel (95) and the traction rotating pulley group (96) on the frame body (10) and then fixedly connected to the cover body (911) of the hook (91), and the hook body (912) of the hook (91) is connected to the lifting ring (922); the flexible rope (94), the guide wheel (95), the traction rotating pulley group (96), and the weight (93) are each provided in two groups, the guide wheel (95) is respectively fixed to the column of the frame body (10), and the traction rotating pulley group (96) is respectively fixed to the two corresponding top beams of the frame body (10).

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