Lower artificial limb applying magneto-rheological damper

Abstract

The utility model relates to a lower artificial limb applying a magnetorheological damper. The lower artificial limb comprises a receiving cavity, a four-bar mechanism, a single-rod single-cylinder type magnetorheological damper, a disc type magnetorheological damper and an ankle joint, the receiving cavity is connected to the connecting disc through threads, the connecting disc is installed on the upper end face of the four-connecting-rod mechanism, the four-connecting-rod mechanism comprises a front pivot joint rod, an upper pivot joint rod, a telescopic rear pivot joint rod and a shank top end face, and the telescopic rear pivot joint rod is composed of a spring and a sleeve. The upper lifting lug and the lower lifting lug are connected and fixed through bolts, the disc type magnetorheological damper is connected through a stepping motor in a matched mode through a coupler, the ankle joint is matched with the shank connecting piece through a transmission shaft, and a pressure sensor is installed at the side end of the ankle joint. The utility model aims to provide the lower artificial limb applying the magneto-rheological damper, the buffer performance of the artificial limb is better when the artificial limb is bent and the foot touches the ground, and the ankle can rotate.

Description

Technical Field

[0001] The utility model belongs to the technical field of artificial limbs, and in particular relates to a lower artificial limb using a magnetorheological damper. Background Art

[0002] As traffic accidents, natural disasters, diseases, or wars increase the number of disabled people, the demand for prosthetic limbs has also increased significantly. For lower limb amputees, the loss of the ability to walk has brought a lot of inconvenience to their daily lives. Currently, the most effective way to restore the ability to walk is to use prosthetic limbs. In existing designs, most knee joints with magnetorheological dampers use a four-bar linkage with a fixed length to connect to the damper, which still has the problem of large vibration and small cushioning. In most current designs, the ankle joint is integrated in the overall structure of most prosthetic limbs and cannot rotate. It cannot bend when walking on different road surfaces, and its adaptability is even worse.

[0003] Therefore, to address the above problems, it is necessary to design a new lower prosthesis using magnetorheological dampers. Utility Model Content

[0004] The purpose of the utility model is to provide a lower prosthesis using a magnetorheological damper. By adding a spring to the telescopic rear pivot rod in the four-bar linkage, and adding a disc-type magnetorheological damper and a bevel gear to adjust the ankle joint, the problems of poor cushioning performance of the prosthesis when bending and when the foot touches the ground and the integrated knee-ankle structure are solved.

[0005] The utility model is achieved through the following technical solutions:

[0006] The utility model relates to a lower prosthesis using a magnetorheological damper, comprising: a receiving cavity, a four-bar linkage, a single-rod single-tube magnetorheological damper, a disc-type magnetorheological damper, and an ankle joint. The utility model is characterized in that the receiving cavity is tightly connected by a connecting disk through threaded fit, the four-bar linkage is composed of a front pivot rod, an upper pivot rod, a telescopic rear pivot rod and the top of the calf, wherein the telescopic rear pivot rod is composed of a spring and its sleeve that cooperate with each other, the calf is equipped with a microcontroller and a battery, the single-rod The single-tube magnetorheological damper is connected to the upper hanging ear and the lower hanging ear of the calf by an intermediate connecting rod bolt. The disc-type magnetorheological damper is connected to the damper input shaft by a stepper motor in the calf and a coupling. A pair of bevel gears are installed at one end of the damper output shaft. The bevel gears are installed on the rotating shaft of its output shaft and the connecting plate. The connecting plate is fixed to the lower end of the calf by bolts. The ankle joint includes an ankle joint connecting plate and the sole of the foot. There is a pressure measuring device connected by screws and a side-mounted pressure sensor at the heel.

[0007] Preferably, the receiving cavity is connected to the connecting plate at the lower portion thereof by a thread, and then is mounted on the upper end surface of the four-bar linkage using a countersunk hole.

[0008] Preferably, the four-bar linkage is connected by a front pivot rod, an upper pivot rod, a telescopic rear pivot rod and the upper end of the calf via a hinge.

[0009] Preferably, there is a threaded hole at the bottom of the rotating bracket on the telescopic rear pivot rod, the locking sleeve is fixed to its bottom by a screw, the spring is installed in the locking sleeve to fix its upper end, the bottom is fixed to the support device, and one side of the locking sleeve is connected to the middle connecting rod by a locking screw.

[0010] Preferably, the single-rod single-tube magnetorheological damper is interference fit with the inside of the calf, the upper lifting ear of the single-rod single-tube magnetorheological damper is tightly connected to the middle connecting rod through bolts, and the lower lifting ear is fixed to the calf using bolts.

[0011] Preferably, the disc-type magnetorheological damper is composed of a stepper motor fixed in the calf, which is connected to the damper input shaft through a key to form an interference fit. One end of the damper output shaft is equipped with a pair of bevel gears with an intersection angle of 90° that cooperate with the rotating shaft. The bevel gears are fixed on the rotating shaft of the connecting plate through deep groove ball bearings. Both sides of the rotating shaft and the connecting plate are fixed with elastic retaining rings. An angle sensor is installed on the side end of the rotating shaft, and the angle sensor is connected to the microcontroller.

[0012] Preferably, the ankle joint connecting plate is provided with a threaded hole, the sole of the foot is threadedly connected to the hole, and the heel is connected to a pressure measuring device via screws and a pressure sensor is installed on its side.

[0013] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0014] 1. This utility model uses a retractable rear pivot rod instead of a conventional rear connecting rod. By adding a spring, the connecting rod length can be changed. This, in turn, works together with a single-rod, single-tube magnetorheological damper to increase the damping force, thereby further improving the cushioning performance of the patient's knee joint.

[0015] 2. The utility model uses a disc-type magnetorheological damper at the lower end of the calf to drive a bevel gear to adjust the rotation of the ankle joint, thereby achieving a 0-25° bend of the ankle joint of the lower prosthesis.

[0016] 3. The utility model has a simple structure and is easy to repair and replace parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments recorded in this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0018] Figure 1 A three-dimensional schematic diagram of an embodiment of the present invention;

[0019] Figure 2 This is another perspective schematic diagram of an embodiment of the present utility model;

[0020] Figure 3 A side view of a retractable rear pivot rod according to an embodiment of the present invention;

[0021] Figure 4 This is a cross-sectional view of a single-rod, single-tube magnetorheological damper according to an embodiment of the present invention;

[0022] Figure 5 This is a cross-sectional view of the lower end of the calf according to an embodiment of the present invention;

[0023] Figure 6 A partial cross-sectional view of a disc-type magnetorheological damper according to an embodiment of the present invention;

[0024] Figure 7 A side view of an ankle joint according to an embodiment of the present invention;

[0025] Figure: 1, receiving cavity; 2, connecting plate; 3, four-bar linkage; 31, upper pivot rod; 32, telescopic rear pivot rod; 321, rotating bracket; 322, locking sleeve; 323, spring; 324, supporting device; 33, front pivot rod; 4, intermediate connecting rod; 5, single-rod single-tube magnetorheological damper; 51, piston rod; 52, upper end cover; 53, damper housing; 54, excitation coil; 55, magnetorheological fluid; 56, floating piston; 57, nitrogen; 58, lower end cover; 5 9. Lower connecting rod; 6. Lower leg; 7. Stepper motor; 8. Coupling; 9. Disc-type magnetorheological damper; 91. Damper input shaft; 92. Right end cover; 93. Left end cover; 94. Damper output shaft; 10. Bevel gear; 11. Rotating shaft; 12. Ankle joint; 121. Ankle joint connecting plate; 122. Sole of foot; 13. Pressure measuring device; 14. Pressure sensor; 15. Angle sensor; 16. Elastic retaining ring; 17. Connecting plate; 18. Microcontroller; 19. Battery. DETAILED DESCRIPTION

[0026] In order to describe the structural features, technical solutions and functional characteristics of the present invention in detail, the present invention will be further described with reference to the accompanying drawings and embodiments:

[0027] See also Figure 1-7The utility model is a lower prosthesis using a magnetorheological damper, comprising: a receiving cavity (1), a four-bar linkage (3), a single-rod single-tube magnetorheological damper (5), a disc-type magnetorheological damper (9), and an ankle joint (12), characterized in that the receiving cavity (1) is tightly connected by a connecting disk (2) through threaded fitting, the four-bar linkage (3) is composed of a front pivot rod (33), an upper pivot rod (31), a telescopic rear pivot rod (32) and the top of a calf (6), wherein the telescopic rear pivot rod (32) is composed of a spring (323) and its sleeve that cooperate with each other, the calf (6) is equipped with a microcontroller (18) and a battery (19), the single-rod single-tube magnetorheological damper The damper (5) is bolted to an upper hanging ear fixed to the lower hanging ear of the calf (6) by an intermediate connecting rod (4); the disc-type magnetorheological damper (9) is connected to the damper input shaft (91) by a stepping motor (7) in the calf (6) in conjunction with a coupling (8); a pair of bevel gears (10) are installed at one end of the damper output shaft (94); the bevel gears (10) are installed on the output shaft and the rotating shaft (11) of the connecting plate (17); the connecting plate (17) is fixed to the lower end of the calf (6) by bolts; the ankle joint (12) includes an ankle joint connecting plate (121) and a sole (122); a pressure measuring device (13) connected by screws and a side-mounted pressure sensor (14) are provided at the heel.

[0028] The receiving cavity (1) is connected to the connecting plate (2) at its lower portion by a threaded connection, and then mounted on the upper end surface of the four-bar linkage (3) using a countersunk hole, thereby fixing the connecting plate (2) and the four-bar linkage (3), thereby achieving the connection between the patient's thigh and the receiving cavity (1).

[0029] The four-bar linkage (3) is connected by a front pivot rod (33), an upper pivot rod (31), a telescopic rear pivot rod (32) and the upper end of the calf (6) through a hinge, simulating a normal human knee joint and achieving 0-100° flexion and rotation.

[0030] The bottom of the rotating bracket (321) on the telescopic rear pivot rod (32) has a threaded hole, the locking sleeve (322) is fixed to the bottom thereof by screws, the spring (323) is installed in the locking sleeve (322) to fix the upper end thereof, and the bottom is fixed to the supporting device (324), and one side of the locking sleeve (322) is connected to the middle connecting rod (4) by a locking screw, so that the spring (323) will not be twisted and deformed during the compression process, ensuring that it is compressed and deformed in the locking sleeve (322).

[0031] Among them, the single-rod single-tube magnetorheological damper (5) is interference-fitted with the inside of the calf (6), the upper hanging ear of the single-rod single-tube magnetorheological damper (5) is tightly connected to the middle connecting rod (4) through bolts, and the lower hanging ear is fixed to the calf (6) using bolts, so that the damper and the spring (323) can be used in parallel to generate a greater damping force, and the buffering performance is improved.

[0032] The disc-type magnetorheological damper (9) is formed by a stepper motor (7) fixed in the shank (6) and a coupling (8) connected to the damper input shaft (91) through a key connection to form an interference fit. One end of the damper output shaft (94) is equipped with a pair of bevel gears (10) with an intersection angle of 90 degrees that match the rotating shaft (11). The bevel gears (10) are fixedly mounted on the rotating shaft (11) of the connecting plate (17) through deep groove ball bearings. The rotating shaft (11) and the connecting plate (17) are matched. Both sides are fixed with elastic retaining rings (16), and an angle sensor (15) is installed on the side end of the rotating shaft (11). The angle sensor (15) is connected to a microcontroller (18). The problem of excessive rotation speed of the rotating shaft of the stepping motor (7) is changed through a disc-type magnetorheological damper (9). The damping force generated by the magnetorheological fluid (55) after power is applied in the damper is adjusted and transmitted to the damper output shaft (94), thereby driving the rotating shaft (11) to rotate, thereby achieving bending of the ankle joint (12).

[0033] The ankle joint connecting plate (121) is provided with a threaded hole, the sole (122) is threadedly connected to the hole, the heel is connected to a pressure measuring device (13) and a pressure sensor (14) installed on its side via screws, and the pressure measuring device (13), the pressure sensor (14) and the angle sensor (15) transmit signals to a microcontroller (18) to thereby change the magnitude of the current of the excitation coil (54).

[0034] The working process of the utility model device:

[0035] After the patient places the thigh in the receiving cavity (1), when the thigh flexes, the receiving cavity (1) drives the upper pivot rod (31) connected to the connecting plate (2) to rotate downward and bend, thereby causing the telescopic rear pivot rod (32) to rotate forward, and the spring (323) to bend and deform. At the same time, the excitation coil (54) of the single-rod single-tube magnetorheological damper (5) and the disc-type magnetorheological damper (9) has been energized. As the telescopic rear pivot rod (32) bends forward, the middle connecting rod (4) drives the upper hanging ear of the single-rod single-tube magnetorheological damper (5) connected thereto downward, and at this time, the single-rod single-tube magnetorheological damper (5) and the spring (323) jointly increase the damping force. When the ankle joint (12) bends, the stepper motor (7) transmits the rotation to the damper input shaft (91) of the disc-type magnetorheological damper (9) through the coupling (8). The damper input shaft (91) is driven by the magnetorheological fluid (55) after being energized to rotate the damper output shaft (94). The damper output shaft (94) drives the bevel gear (10) on the rotating shaft (11) to rotate, thereby achieving the bending of the ankle joint (12). The angle sensor (15) at the side end of the rotating shaft (11) transmits the rotation angle to the microcontroller (18). When a certain current is reached, the stepper motor (7) reaches the reset rotation, thereby also driving the ankle joint (12) to reset. When the pressure measuring device (13) receives pressure and undergoes elastic deformation, its pressure change is transmitted to the connected pressure sensor (14). Subsequently, the pressure signal is transmitted to the signal receiving port of the microcontroller (18). The battery (19) is connected to the microcontroller (18), which dynamically adjusts the current intensity output to the specific excitation coil (54) based on the pressure value fed back by the pressure sensor (14). Ultimately, this series of controls interacts with the physical effects to achieve the purpose of buffering and ankle flexion.

[0036] It should be understood that the above embodiments of the present invention are merely examples for illustrating the present invention in detail and are not intended to limit the embodiments of the present invention. A person skilled in the art would be able to make various modifications or variations based on the above description. Any modifications or variations of the technical solution of the present invention are also considered to be within the scope of protection of the appended claims.

Claims

1. A lower prosthesis using a magnetorheological damper, comprising: A receiving cavity (1), a four-bar linkage (3), a single-rod single-tube magnetorheological damper (5), a disc-type magnetorheological damper (9), and an ankle joint (12), characterized in that the receiving cavity (1) is tightly connected by a connecting disk (2) through threaded fitting, the four-bar linkage (3) is composed of a front pivot rod (33), an upper pivot rod (31), a telescopic rear pivot rod (32) and the top of a calf (6), wherein the telescopic rear pivot rod (32) is composed of a spring (323) and its sleeve that cooperate with each other, the calf (6) is equipped with a microcontroller (18) and a battery (19), the single-rod single-tube magnetorheological damper (5) is composed of an intermediate link rod (4 ) bolts are connected to fix the upper hanging ear and the lower hanging ear of the calf (6); the disc-type magnetorheological damper (9) is connected to the damper input shaft (91) by a stepping motor (7) in the calf (6) in conjunction with a coupling (8); a pair of bevel gears (10) are installed at one end of the damper output shaft (94); the bevel gears (10) are installed on the output shaft and the rotating shaft (11) of the connecting plate (17); the connecting plate (17) is fixed to the lower end of the calf (6) by bolts; the ankle joint (12) includes an ankle joint connecting plate (121) and a sole (122); a pressure measuring device (13) connected by screws and a side-mounted pressure sensor (14) are provided at the heel.

2. The lower prosthesis using a magnetorheological damper according to claim 1, characterized in that: The receiving cavity (1) is connected to the connecting plate (2) at its lower portion via a threaded connection, and is then mounted on the upper end surface of the four-bar linkage (3) using a countersunk hole.

3. The lower prosthesis using a magnetorheological damper according to claim 1, characterized in that: The four-link mechanism (3) is connected by a front pivot rod (33), an upper pivot rod (31), a telescopic rear pivot rod (32) and the upper end of the calf (6) through a hinge.

4. The lower prosthesis using a magnetorheological damper according to claim 3, characterized in that: The bottom of the rotating bracket (321) on the telescopic rear pivot rod (32) is provided with a threaded hole, the locking sleeve (322) is fixed to the bottom thereof by screws, the spring (323) is installed in the locking sleeve (322) to fix the upper end thereof, and the bottom is fixed to the supporting device (324).

5. The lower prosthesis using a magnetorheological damper according to claim 4, characterized in that: The single-rod single-tube magnetorheological damper (5) is interference-fitted with the inside of the shank (6); the upper hanging ear of the single-rod single-tube magnetorheological damper (5) is tightly connected to the middle connecting rod (4) through bolts, and the lower hanging ear is fixed to the shank (6) using bolts.

6. The lower prosthesis using a magnetorheological damper according to claim 1, characterized in that: The disc-type magnetorheological damper (9) is formed by a stepper motor (7) fixed in the shank (6) and a coupling (8) connected to the damper input shaft (91) through a key to form an interference fit. One end of the damper output shaft (94) is equipped with a pair of bevel gears (10) with an intersection angle of 90 degrees that match the rotating shaft (11). The bevel gears (10) are fixedly mounted on the rotating shaft (11) of the connecting plate (17) through deep groove ball bearings. Both sides of the rotating shaft (11) and the connecting plate (17) are fixed with elastic retaining rings (16). An angle sensor (15) is installed on the side end of the rotating shaft (11), and the angle sensor (15) is connected to a microcontroller (18).

7. The lower prosthesis using a magnetorheological damper according to claim 1, characterized in that: The ankle joint connecting plate (121) is provided with a threaded hole, the sole (122) is threadedly connected to the hole, and the heel is connected to a pressure measuring device (13) through screws and a pressure sensor (14) is installed on the side thereof.

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