Limb rehabilitation training device with variable stiffness function

Abstract

The utility model relates to the technical field of rehabilitation instruments, and discloses a limb rehabilitation training device with a variable stiffness function, which comprises a casing, a support frame is fixedly mounted in the casing, two pairs of bearing seats are fixedly mounted in the support frame, and rotating shafts are rotatably mounted in the bearing seats; a guide shaft support is rotationally mounted in the center of the supporting frame through a rotating seat, one end of a guide shaft is fixedly mounted in the guide shaft support, and the guide shaft is sleeved with a sliding block; the ends, away from each other, of the two rotating shafts on the upper side are each rotationally provided with one end of a swing rod, the other ends of the swing rods are fixedly provided with the same cross rod, the sliding blocks are provided with elastic pieces, and the supporting frame is provided with an adjusting assembly used for lifting the sliding blocks. The limb training rigidity of a patient can be changed, the structure is simple, work is stable, and therefore on the premise that man-machine interaction safety is guaranteed, the control accuracy of the training device can be kept accurate for a long time, and the device is more reliable in overall operation, longer in service life and better in durability.

Description

Technical Field

[0001] This utility model relates to the field of rehabilitation equipment technology, specifically a limb rehabilitation training device with variable stiffness function. Background Technology

[0002] Limb motor dysfunction can lead to a decline in patients' quality of life. However, with active rehabilitation treatment, most limb motor dysfunctions caused by disease can be reversed and patients can regain their ability to live independently. Limb motor dysfunctions caused by natural aging can also be alleviated and improved to some extent.

[0003] Limb rehabilitation training for patients includes active training and passive training. Passive training is suitable for patients in the early stage of rehabilitation, when they cannot effectively control their muscles, their limbs are weak, and they do not have the ability to move actively. They need external force to complete flexion and extension movements of their limbs. When patients have recovered to a certain level, or can complete movements partially or completely without the help of external force, active training can be carried out, in which patients actively use their own limb strength to achieve flexion and extension movements.

[0004] In the prior art, for example, the invention patent with publication number CN113440376A discloses a human upper limb rehabilitation training device with variable stiffness function. It is equipped with independently driven variable stiffness joints to achieve stiffness adjustment that is independently decoupled from rehabilitation movements. While ensuring the working stability of the rehabilitation training device, it improves the safety of the rehabilitation training device and avoids rigid impact from the rehabilitation training device, which could cause secondary injury to the patient. Another example is the invention patent with publication number CN117338567A, which discloses a variable stiffness exoskeleton rehabilitation robot system. The exoskeleton rehabilitation robot is driven by a variable stiffness drive system. By controlling the rotational position of two drive motors in the system, the position and stiffness of the exoskeleton joints can be controlled simultaneously.

[0005] The above variable stiffness working mode can provide a variable stiffness training mode, and also has the safety of human-computer interaction. However, the method of centrally adjusting stiffness and providing drive at the joints requires miniaturization of the parts. Correspondingly, the strength requirements of the parts will increase, resulting in greater manufacturing difficulty and higher cost. In the long run, this will lead to a shortened service life of the training device, reduced control accuracy, and poor durability.

[0006] Therefore, in order to provide a more reliable stiffness adjustment structure and improve overall durability, a limb rehabilitation training device with variable stiffness function is proposed. Utility Model Content

[0007] The purpose of this invention is to provide a limb rehabilitation training device with variable stiffness function, which solves the problems mentioned in the background art by means of a more reliable stiffness adjustment method and a simplified and durable structure.

[0008] To achieve the above objectives, this utility model provides the following technical solution: a limb rehabilitation training device with variable stiffness function, comprising a housing, a support frame fixedly installed inside the housing, two pairs of bearing seats fixedly installed inside the support frame, and a rotating shaft rotatably installed in each bearing seat; a guide shaft support is rotatably installed at the center of the support frame via a rotating seat, one end of a guide shaft is fixedly installed inside the guide shaft support, and a slider is sleeved on the guide shaft; one end of a swing rod is rotatably installed at each of the two mutually distant ends of the upper rotating shaft, the other end of the swing rod is fixedly installed with the same crossbar, the slider is equipped with an elastic element, the crossbar is located inside the elastic element, and the support frame is provided with an adjustment component for raising and lowering the slider.

[0009] Specifically, the adjustment assembly includes a driven gear and a crank. Two lower rotating shafts are fixedly mounted with drive gears, and two upper rotating shafts are fixedly mounted with driven gears. A pair of servo motors are fixedly mounted on the support frame. The output ends of the servo motors are respectively connected to the lower rotating shafts via couplings. The drive gears and driven gears on the same side are meshed and assembled. The ends of the driven gears that are close to each other are eccentrically mounted with one end of a crank. The other end of the crank is rotatably assembled with the left and right sides of the slider respectively.

[0010] Furthermore, the diameter of the driving gear is smaller than the diameter of the driven gear.

[0011] Furthermore, the axis of the upper rotating shaft coincides with the axis of the pin in the rotating seat.

[0012] The elastic element can be configured in the following ways:

[0013] In the first form, the elastic element consists of two straight-plate springs, with the same end of each spring mounted on the front and rear sides of the slider, respectively.

[0014] In the second form, the elastic element is a U-shaped spring sheet, with its two ends respectively installed on the front and rear sides of the slider.

[0015] Furthermore, a linear bearing is fixedly installed inside the slider, and the guide shaft is slidably assembled with the linear bearing.

[0016] Furthermore, the crossbar is rotatably mounted with a sleeve, which is located inside the elastic element.

[0017] Specifically, the housing has clearance grooves for the passage of the swing arm, elastic element and crank, and a controller is installed on the outside of the housing via a cable.

[0018] Specifically, a handle or strap is installed at the end of the crossbar, and straps are installed on the side wall of the housing.

[0019] Compared with the prior art, the beneficial effects of this utility model are:

[0020] By combining structures such as crossbar, swing bar, elastic element and adjustment component, the distance between the slider and crossbar can be adjusted, thereby changing the stiffness of the elastic element acting on the crossbar, meeting the needs of patients for active and passive training. This variable stiffness adjustment method is convenient to adjust and can maintain a precise force over a long period of time.

[0021] The use of more stable gear transmission, rotary connection and sliding assembly in various parts makes the structure simple and the operation stable. Thus, while meeting the requirements of variable stiffness adjustment and human-machine interaction safety, the control accuracy of the training device can be maintained for a long time, the overall operation of the device is more reliable, the service life is longer and the durability is better. Attached Figure Description

[0022] Figure 1 This is a schematic front view of one usage form of the present utility model;

[0023] Figure 2 This is a schematic front view of another usage form of the present utility model;

[0024] Figure 3 This is a three-dimensional schematic diagram of the internal structure of the casing of this utility model;

[0025] Figure 4 This is a three-dimensional schematic diagram of the structure of the elastic element of this utility model (Form 1).

[0026] Figure 5 This is a three-dimensional schematic diagram of the second type of elastic element of this utility model.

[0027] In the diagram: 1 Support frame, 2 Servo motor, 3 Coupling, 4 Crank, 5 Shaft, 6 Drive gear, 7 Driven gear, 8 Guide shaft support, 9 Slider, 10 Elastic element, 11 Sleeve, 12 Crossbar, 13 Swing rod, 14 Guide shaft, 15 Linear bearing, 16 Rotary seat, 17 Housing, 18 Controller, 19 Strap, 20 Handle, 21 Clearance groove. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] Please see Figure 1 and Figure 3This utility model provides a limb rehabilitation training device with variable stiffness function, including a housing 17. A support frame 1 is fixedly installed inside the housing 17. The support frame 1 is used to provide mounting support for the components. Two pairs of bearing seats are fixedly installed inside the support frame 1. A rotating shaft 5 is rotatably installed in each bearing seat, which can reduce the rotational resistance of the rotating shaft 5. A guide shaft support 8 is rotatably installed at the center of the support frame 1 via a rotating seat 16. One end of a guide shaft 14 is fixedly installed inside the guide shaft support 8. A slider 9 is sleeved on the guide shaft 14. The slider 9 can slide along the axial direction of the guide shaft 14. The rotating seat 16 is composed of two bases rotatably installed by a pin, so that the guide shaft support 8 can drive the components on it to complete the swinging action.

[0030] Two rotating shafts 5 on the upper side are rotatably mounted with one end of a swing rod 13 at their far ends. The other end of the swing rod 13 is fixedly mounted with the same crossbar 12. The slider 9 is equipped with an elastic element 10, and the crossbar 12 is located inside the elastic element 10. The support frame 1 is provided with an adjustment component for raising and lowering the slider 9. When the adjustment component is in the adjustment mode, it can raise and lower the slider 9 along the guide shaft 14 and position it, changing the distance between the slider 9 and the crossbar 12. This changes the stiffness of the elastic element 10 acting on the crossbar 12 and changes the effective length of the elastic element 10, thereby matching the limb rehabilitation needs of different patients.

[0031] Specifically, such as Figure 3 As shown, the adjustment assembly includes a driven gear 7 and a crank 4. Two lower rotating shafts 5 are fixedly mounted with drive gears 6, and two upper rotating shafts 5 are fixedly mounted with driven gears 7. A pair of servo motors 2 are fixedly mounted on the support frame 1. The output ends of the servo motors 2 are connected to the lower rotating shafts 5 via couplings 3. Couplings 3 have the function of absorbing vibration and improving transmission quality. In addition, couplings 3 can prevent the working end from bearing excessive load, and have the function of overload protection, avoiding accidental damage to the patient's limbs and parts. The drive gears 6 and driven gears 7 on the same side are meshed and assembled, and the diameter of the drive gear 6 is smaller than the diameter of the driven gear 7, which plays the role of speed reduction and torque increase, which is beneficial to transmission and force application. The ends of the driven gears 7 that are close to each other are eccentrically mounted with one end of the crank 4. The other end of the crank 4 is rotatably assembled with the left and right sides of the slider 9 respectively. The rotation method here can be that the driven gears 7 and the side walls of the slider 9 are fixedly mounted with pins, and the two ends of the crank 4 are mounted on the pins through bearings, thereby realizing smooth rotation.

[0032] Two servo motors 2 can simultaneously rotate two drive gears 6 in opposite directions, thereby causing two driven gears 7 to rotate in opposite directions. For example, the left driven gear 7 rotates clockwise and the right driven gear 7 rotates counterclockwise, which can lift the slider 9 upward along the guide shaft 14 via the crank 4, and conversely, pull the slider 9 downward along the guide shaft 14 to complete the lifting and lowering movement of the slider 9. When the two driven gears 7 are relatively stationary, the position of the slider 9 can be fixed, and the slider 9 will not move freely.

[0033] In addition, the two servo motors 2 can also rotate the two drive gears 6 in the same direction at the same time. At this time, the slider 9 is stationary, and the guide shaft support 8, slider 9 and elastic element 10 are oscillating directly with the upper rotating shaft 5 as the center, thereby applying an oscillating force to the crossbar 12, and finally making the crossbar 12 and the swing rod 13 realize the oscillating action.

[0034] Furthermore, the axis of the upper rotating shaft 5 and the axis of the pin in the rotating seat 16 are set to coincide, which can ensure that the swing center of the guide shaft support 8 and the swing rod 13 are the same and there will be no motion interference.

[0035] The elastic element 10 can be configured in the following ways:

[0036] Form 1, such as Figure 4 As shown, the elastic element 10 consists of two straight-plate springs, with the same end of each straight-plate spring connected by screws and installed on the front and rear sides of the slider 9 respectively. During passive training, the straight-plate springs on the front and rear sides apply force to the crossbar 12 to drive the crossbar 12 to swing. During active training, the crossbar 12 applies force to the straight-plate springs on the front and rear sides respectively, and the straight-plate springs can provide swing resistance respectively.

[0037] Form two, such as Figure 5 As shown, the elastic element 10 is a U-shaped spring sheet, and the two ends of the U-shaped spring sheet are respectively installed on the front and rear sides of the slider 9 by means of screw connection. When the patient is passively trained, the front and rear sides of the U-shaped spring sheet apply force to the crossbar 12 to complete the swing drive of the crossbar 12. When the patient is actively trained, the crossbar 12 applies force to the front and rear sides of the U-shaped spring sheet, and the U-shaped spring sheet can provide a uniform swing resistance as a whole.

[0038] Whether the elastic force is provided by two straight spring plates or by a uniform elastic force provided by a single U-shaped spring plate, it will not affect the achievement of this action. The appropriate method can be chosen flexibly according to the patient's rehabilitation needs and the application of the device.

[0039] Specifically, such as Figure 4As shown, a linear bearing 15 is fixedly installed inside the slider 9, and the guide shaft 14 is slidably assembled with the linear bearing 15. The linear bearing 15 is an existing component, which can reduce the resistance to the movement of the slider 9.

[0040] A sleeve 11 is rotatably mounted on the crossbar 12. The sleeve 11 is located inside the elastic element 10. For example, when the patient is actively training, the slider 9 does not swing. The patient actively applies force to the crossbar 12. At this time, the swing of the swing rod 13 will cause a small relative displacement between the elastic element 10 and the crossbar 12, resulting in friction. The sleeve 11 can avoid this friction by rolling, making the movement smoother.

[0041] Specifically, the housing 17 has a clearance groove 21 for the swing arm 13, the elastic element 10 and the crank 4 to avoid obstructing the completion of the swinging motion; a controller 18 is installed on the outside of the housing 17 via a cable, and two servo motors 2 are electrically connected to the controller 18 via cables. The controller 18 and the servo motors 2 are powered by a battery installed inside the housing 17 or by an external power supply, and the working mode is set by the controller 18. In this way, the external controller 18 can be easily set and operated by patients or nursing staff no matter how the housing 17 is placed.

[0042] The following are the available usage options:

[0043] A handle 20 or a strap 19 is installed at the end of the crossbar 12 (either the left or right end, depending on the patient's side of use). A strap 19 is installed on the side wall of the housing 17 (either the left or right side, depending on the patient's side of use). The strap 19 installed on the housing 17 is installed by screw connection to bind the thigh or upper arm. The handle 20 and strap 19 installed on the crossbar 12 are provided with screws, and the end of the crossbar 12 has a screw hole. The handle 20 or strap 19 can be quickly installed and removed by screwing the screws and screw holes, which is convenient to match according to the patient's needs. For example, if the patient has sufficient hand grip strength, the handle 20 can be used, which is more conducive to self-exertion and rehabilitation training. If the patient has insufficient hand grip strength, or if it is used for lower leg fixation, the strap 19 can be used to bind the wrist or lower leg.

[0044] In addition, the side wall of the housing 17 without the strap 19 can be installed on the existing adjustment frame (which has the functions of lifting and swinging) by means of screw connection, so as to make it convenient to adapt and adjust the position of the device to accommodate the height and angle of different limbs.

[0045] The working principle of this embodiment:

[0046] Before use, according to the flexion and extension angle requirements of the limb, first operate the controller 18 to make the two drive gears 6 rotate counterclockwise at the same time, and swing the horizontal bar 12 forward to adjust to the appropriate initial angle; then in the adjustment mode, adjust the lifting slider 9 of the adjustment component to change the stiffness of the elastic element 10 acting on the horizontal bar 12.

[0047] When in use, the housing 17 can be placed on a table or chair or installed on an adjustment frame. One side of the limb is fixed by the straps 19 on the housing 17, and the other side of the limb is fixed by the handles 20 or straps 19 on the crossbar 12.

[0048] In Mode 1, the patient can perform passive training. At this time, the two drive gears 6 rotate clockwise and counterclockwise repeatedly, and the horizontal bar 12 on the swing rod 13 swings back and forth through the elastic element 10 to assist in completing the flexion and extension movements of the limb.

[0049] In Mode 2, when the patient performs active training with small-range swinging, the two drive gears 6 remain stationary, and the patient can flex and extend their limbs independently, applying force to the elastic element 10 via the crossbar 12. At this time, the slider 9 can also be raised and lowered again by adjusting the component to change the stiffness of the elastic element 10 acting on the crossbar 12 to match the needs of rehabilitation training.

[0050] In mode three, when the patient performs active training with a wide range of swinging motions, the patient can flex and extend their limbs on their own, applying force to the elastic element 10 via the crossbar 12, while simultaneously swinging the swing rod 13, the slider 9, and the two driven gears 7. At this time, the two servo motors 2 will also rotate clockwise and counterclockwise in sync with the limb swinging motion. However, the servo motors 2 will maintain a certain lag response, and together with the elastic element 10, they can ensure that there is always swinging resistance on the crossbar 12.

[0051] The patient's limb spasms are absorbed by the elastic element 10, which provides excellent human-computer interaction safety for both the patient and the device. The stable structure can maintain the accuracy of stiffness adjustment for a long time, making the overall device more stable and durable.

[0052] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0053] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A limb rehabilitation training device with variable stiffness function, comprising a casing (17), characterized in that: The inside of the shell (17) is fixedly installed with a support frame (1), the inside of the support frame (1) is fixedly installed with two pairs of bearing seats, the bearing seats are all rotationally installed with rotating shafts (5); the center of the support frame (1) is rotationally installed with a guide shaft support (8) through a rotating seat (16), one end of the guide shaft support (8) is fixedly installed with a guide shaft (14), the guide shaft (14) is sleeved with a sliding block (9); the ends of the upper two rotating shafts (5) are all rotationally installed with one end of an oscillating rod (13), the other end of the oscillating rod (13) is fixedly installed with a same cross rod (12), the sliding block (9) is installed with an elastic element (10), the cross rod (12) is located in the elastic element (10), the support frame (1) is provided with an adjusting assembly for lifting the sliding block (9).

2. The limb rehabilitation training device with variable rigidity function according to claim 1, characterized in that: The adjusting assembly comprises a driven gear (7) and a crank (4), the lower two rotating shafts (5) are fixedly installed with driving gears (6), the upper two rotating shafts (5) are fixedly installed with driven gears (7), the support frame (1) is fixedly installed with a pair of servo motors (2), the output ends of the servo motors (2) are respectively connected with the lower rotating shafts (5) through couplings (3), the driving gears (6) and the driven gears (7) on the same side are engaged and assembled, the ends of the driven gears (7) close to each other are all rotationally installed with one end of a crank (4) at an eccentric position, the other end of the crank (4) is rotationally assembled with the left and right sides of the sliding block (9).

3. The limb rehabilitation training device with variable rigidity function according to claim 2, characterized in that: The diameter of the driving gear (6) is smaller than the diameter of the driven gear (7).

4. The limb rehabilitation training device with variable rigidity function according to claim 1, characterized in that: The axis of the upper rotating shaft (5) and the axis of the pin in the rotating seat (16) are arranged in coincidence.

5. The limb rehabilitation training device with variable rigidity function according to claim 1, characterized in that: The elastic element (10) is composed of two straight plate type elastic sheets, the same ends of the straight plate type elastic sheets are respectively installed on the front and back sides of the sliding block (9).

6. The limb rehabilitation training device with variable rigidity function according to claim 1, characterized in that: The elastic element (10) is a U-shaped elastic sheet, the two ends of the U-shaped elastic sheet are respectively installed on the front and back sides of the sliding block (9).

7. The limb rehabilitation training device with variable rigidity function according to claim 1, characterized in that: The inside of the sliding block (9) is fixedly installed with a linear bearing (15), the guide shaft (14) is slidingly assembled with the linear bearing (15).

8. The limb rehabilitation training device with variable rigidity function according to claim 1, characterized in that: The cross rod (12) is rotationally installed with a sleeve (11), the sleeve (11) is located in the elastic element (10).

9. The limb rehabilitation training device with variable rigidity function according to claim 1, characterized in that: The shell (17) is provided with an avoiding groove (21) for the oscillating rod (13), the elastic element (10) and the crank (4), the outside of the shell (17) is installed with a controller (18) through a cable.

10. The limb rehabilitation training device with variable rigidity function according to claim 1, characterized in that: The end of the cross rod (12) is installed with a handle (20) or a binding band (19), the sidewall of the shell (17) is installed with the binding band (19). The end of the cross rod (12) is installed with a handle (20) or a binding band (19), the sidewall of the shell (17) is installed with the binding band (19).

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