Bionic ankle joint and prosthesis

Abstract

The application discloses a bionic ankle joint and a prosthesis. The bionic ankle joint comprises an ankle joint base and a foot mechanism. The ankle joint base is used for connecting with a leg member. The foot mechanism comprises a forefoot member, a hindfoot member and at least one elastic member. The hindfoot member is rotationally connected with the ankle joint base. The forefoot member is rotationally connected with the hindfoot member. One end of the elastic member is connected with the hindfoot member, and the other end of the elastic member is connected with the forefoot member. The elastic member is used for providing an elastic restoring force when the forefoot member rotates relative to the hindfoot member. The application improves the foot fitting degree and enhances the gait stability through multi-joint linkage. The elastic member realizes energy recovery and reuse to reduce energy consumption. Meanwhile, the elastic assistance in the stage of kicking off improves the kicking-off effect, so that the motion characteristics of the bionic ankle joint are closer to the natural state of the human body, and the matching degree of the equipment and the motion characteristics of the human body is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of artificial limbs, in particular to a bionic ankle joint and artificial limb. BACKGROUND

[0002] In the field of rehabilitation aids and bionic machines, the bionic design of the ankle joint is a key link to realize the matching of the device and the human motion characteristics, and to improve the motion stability and flexibility. The human ankle joint, as an important hub connecting the lower leg and the foot, not only needs to bear the weight load of the body, but also needs to realize multi-angle rotation in various motion states such as walking, running and jumping, and provide appropriate cushioning through its biomechanical characteristics to reduce the damage of ground impact force to the limbs, while ensuring the natural fluency of gait.

[0003] In the prior art, the soles of the bionic ankle joint are mostly of a whole structure. Such design often fails to realize self-adaptive fitting when facing uneven ground, and single-point contact phenomenon easily occurs, resulting in a decrease in gait stability, and even an additional burden on the user due to uneven stress. At the same time, in the compression process of the traditional whole sole, most of the energy is directly dissipated, and effective energy recovery and reuse cannot be realized; and in the foot-pushing-off stage, there is not enough energy release to provide active assistance, so that the energy consumption of the whole gait process is high, and the pushing-off effect is poor, which is difficult to match the natural motion characteristics and energy conversion efficiency of the human ankle joint. SUMMARY

[0004] The main purpose of the present application is to provide a bionic ankle joint and artificial limb, which aims to solve the technical problems of poor ground fitting, inability to recover and utilize energy, high gait energy consumption and poor pushing-off effect of the existing bionic ankle joint due to the whole sole design.

[0005] To achieve the above-mentioned purpose, the present application provides a bionic ankle joint, comprising:

[0006] An ankle joint base for connecting with a leg member;

[0007] A sole mechanism comprising a forefoot sole member, a hindfoot sole member and at least one elastic member, the hindfoot sole member being rotationally connected with the ankle joint base, the forefoot sole member being rotationally connected with the hindfoot sole member, one end of the elastic member being connected with the hindfoot sole member and the other end being connected with the forefoot sole member, for providing elastic restoring force when the forefoot sole member rotates relative to the hindfoot sole member.

[0008] In some embodiments, the rear instep member is internally formed with a receiving cavity, and is provided with an opening on a side thereof facing the front instep member, the opening being in communication with the receiving cavity, one end of the front instep member extending into the receiving cavity through the opening, and the portion of the front instep member located in the receiving cavity being pivotally connected to the inner wall of the rear instep member.

[0009] In some embodiments, the front instep member comprises an arc-shaped support portion and a hinged portion protruding from the arc-shaped support portion, the hinged portion extending into the receiving cavity through the opening, and the hinged portion being pivotally connected to the inner wall of the rear instep member via a hinged shaft.

[0010] In some embodiments, the hinged portion is provided with a first limiting protrusion on a side thereof away from the arc-shaped support portion, and the inner wall of the rear instep member is provided with a corresponding limiting plane corresponding to the rotation path of the first limiting protrusion, the limiting plane being used to abut against the end surface of the first limiting protrusion when the front instep member is pivoted to a preset angle relative to the rear instep member.

[0011] In some embodiments, the rear instep member comprises a foot plate and a housing, the housing being connected to the foot plate and enclosing the receiving cavity, and the two ends of the hinged shaft being fixedly connected to two opposite inner walls of the housing.

[0012] In some embodiments, the foot plate is provided with a boss on an end surface thereof facing the housing, the boss being provided with a first mounting cavity, the hinged portion being provided with a second mounting cavity in communication with the first mounting cavity, one end of the elastic member being accommodated in the first mounting cavity and connected to the foot plate, and the other end of the elastic member being accommodated in the second mounting cavity and connected to the hinged portion.

[0013] In some embodiments, the boss is provided with a second limiting protrusion on an end thereof facing the hinged portion, the second limiting protrusion being used to abut against the hinged portion when the front instep member is pivoted to a preset angle relative to the rear instep member.

[0014] In some embodiments, the bionic ankle joint further comprises a damper arranged between the ankle joint base and the rear instep member, the damper comprising a damping body and a piston rod capable of being telescopically extended relative to the damping body, the damping body being pivotally connected to the ankle joint base, and the piston rod being pivotally connected to the rear instep member, so as to be telescopically extended relative to the damping body when the rear instep member is subjected to a force, thereby generating a damping effect on the pivoting of the rear instep member.

[0015] In some embodiments, the hinge point of the damping body and the ankle joint base is a first hinge point, the hinge point of the piston rod and the rear instep member is a second hinge point, the rotation connection point of the front instep member and the rear instep member is a first rotation center, and the rotation connection point of the rear instep member and the ankle joint base is a second rotation center.

[0016] The second rotation center is located at the connection edge of the ankle joint base and the rear instep member, the first hinge point is located on the side of the ankle joint base away from the second rotation center, the second hinge point is located on the side of the rear instep member away from the second rotation center, and the line connecting the first hinge point, the second hinge point, the first rotation center and the second rotation center forms a quadrilateral structure.

[0017] The application also provides a prosthesis, which comprises a leg member and a bionic ankle joint, and the leg member is connected to the end of the ankle joint base away from the rear instep member.

[0018] The bionic ankle joint provided by the application is connected to the leg member through the ankle joint base, the rear instep member in the instep mechanism is rotationally connected to the ankle joint base, the front instep member is rotationally connected to the rear instep member, and the two are connected by an elastic member to form a multi-joint linkage structure. When contacting an uneven ground, the front instep member rotates independently relative to the rear instep member, and the rear instep member rotates independently relative to the ankle joint base, so that the instep and the ground are adaptively fitted through the coordinated movement of the multi-joints to avoid single-point contact. In the gait compression stage, the rotation of the front instep member relative to the rear instep member causes the elastic member to deform and store energy to reduce dissipation. In the foot-pushing-off stage, the elastic member releases energy to provide active assistance to the front instep member through elastic restoring force to assist in completing the pushing-off action. The application improves the instep fitting degree and enhances the gait stability through the multi-joint linkage to avoid the additional burden caused by uneven stress. The elastic member realizes energy recycling and reuse to reduce energy consumption. Meanwhile, the elastic assistance in the foot-pushing-off stage improves the pushing-off effect, so that the motion characteristics of the bionic ankle joint are closer to the natural state of the human body, and the matching degree of the equipment and the motion characteristics of the human body is improved. BRIEF DESCRIPTION OF DRAWINGS

[0019] Fig. 1 FIG. 1 is a structural schematic diagram of an embodiment of the bionic ankle joint of the application;

[0020] Fig. 2 FIG. 2 is an exploded schematic diagram of an embodiment of the bionic ankle joint of the application;

[0021] Fig. 3 FIG. 3 is a cross-sectional schematic diagram of an embodiment of the bionic ankle joint of the application.

[0022] The implementation, functional characteristics and advantages of the application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0023] The embodiments of the present application will be described below in detail with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative efforts belong to the scope of the present application.

[0024] It should be noted that all the directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative position relationship, movement condition, etc. between the components in a certain posture (as shown in the drawings), and the directional indications will change accordingly if the certain posture changes.

[0025] It should also be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or can have a middle element therebetween. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or can have a middle element therebetween.

[0026] In addition, the description of "first", "second", etc. in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can explicitly or implicitly include at least one of the features. In addition, the technical solutions of various embodiments can be combined with each other, but it must be based on the fact that a person skilled in the art can realize it, and when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, and is not within the scope of protection required by the present application.

[0027] Please refer to Figs. 1 to 3 The embodiment of the present application provides a bionic ankle joint 100, which comprises an ankle joint base 10 and a sole mechanism 20. The ankle joint base 10 is used to be connected with a leg member. The sole mechanism 20 comprises a forefoot sole member 21, a hindfoot sole member 22 and at least one elastic member 23. The hindfoot sole member 22 is rotationally connected with the ankle joint base 10. The forefoot sole member 21 is rotationally connected with the hindfoot sole member 22. One end of the elastic member 23 is connected with the hindfoot sole member 22, and the other end is connected with the forefoot sole member 21, which is used to provide elastic restoring force when the forefoot sole member 21 rotates relative to the hindfoot sole member 22.

[0028] The ankle joint base 10 can be detachably or fixedly connected with the leg member through bolt connection, buckle fixing or customized interface design, so as to ensure the coaxiality and stability of the whole bionic ankle joint 100 and the leg structure, and avoid deviation or looseness during movement.

[0029] The forefoot member 21 can adopt an arc-shaped contact surface design to simulate the physiological curve of the human forefoot, and can realize multi-point contact with uneven ground during walking, running and other movements, thereby reducing the gait instability problem caused by single-point contact and improving the adaptability of the device in unstructured environments. The forefoot member 21 is rotationally connected to the ankle joint base 10 at one end and rotationally connected to the rear foot member 22 at the other end, thereby realizing the plantar flexion, dorsiflexion and slight lateral turning movement of the ankle joint, matching the multi-degree-of-freedom movement requirement of the human ankle joint.

[0030] The rear foot member 22 is rotationally connected to the ankle joint base 10 at one end and rotationally connected to the forefoot member 21 at the other end, thereby realizing the plantar flexion, dorsiflexion and slight lateral turning movement of the ankle joint, matching the multi-degree-of-freedom movement requirement of the human ankle joint.

[0031] The elastic member 23 can be made of a high-elasticity coefficient alloy spring, a silica gel material or a memory cotton component. When the forefoot member 21 is pressed and rotated, the elastic member 23 absorbs the ground impact energy through its own deformation, reduces the transmission of ground impact force to the leg, and reduces the damage to the user's limbs, especially for users with weak lower limb function in the rehabilitation assistive device scene.

[0032] Unlike the energy dissipation problem of traditional whole footpads, the elastic member 23 can store the energy absorbed during the landing stage in the form of elastic potential energy and actively release it during the take-off stage, thereby providing a restoring force for the forefoot member 21, reducing the energy consumption of the leg driving mechanism, and improving the take-off force, so that the gait is closer to the natural movement state of the human body. When the footpad contacts an inclined road surface, the relative rotation angle between the forefoot member 21 and the rear foot member 22 changes, and the deformation degree of the elastic member 23 adjusts accordingly. Through the differential elastic restoring force, the footpad posture is corrected in real time to ensure that the foot always maintains stable contact with the ground, thereby improving the traffic ability of the device in unstructured environments such as slope road surfaces and gravel road surfaces.

[0033] During the actual gait cycle, during the landing stage, the ground impact force first acts on the forefoot member 21, pushing the forefoot member 21 to rotate downward relative to the rear foot member 22 around the rotation connection. At this time, the elastic member 23 is stretched or compressed, absorbs the impact energy and converts it into elastic potential energy, thereby avoiding direct transmission of the impact force to the leg. During the take-off stage, the elastic member 23 releases the stored elastic potential energy, generates an elastic restoring force to drive the forefoot member 21 to reset, provides active assistance for the foot to take off the ground, restores the energy conversion process of the natural gait of the human body, and realizes the integration of buffering, energy storage and assistance.

[0034] Compared with the single-point contact problem of the whole sole in the prior art, the bionic ankle joint 100 is connected with the leg member through the ankle joint base 10, the rear sole member 22 in the sole mechanism 20 is rotationally connected with the ankle joint base 10, the front sole member 21 is rotationally connected with the rear sole member 22, and the two are connected by the elastic member 23 to form a multi-joint linkage structure. When contacting the uneven ground, the front sole member 21 rotates independently relative to the rear sole member 22, and the rear sole member 22 rotates independently relative to the ankle joint base 10, so that the sole and the ground are adaptively fitted through the coordinated movement of the multiple joints to avoid single-point contact. In the gait compression stage, the rotation of the front sole member 21 relative to the rear sole member 22 deforms the elastic member 23 to store energy, thereby reducing dissipation. In the foot kick-off stage, the elastic member 23 releases energy to provide active assistance to the front sole member 21 through elastic restoring force to assist in completing the kick-off action.

[0035] The application improves the sole fitting degree through the multi-joint linkage to enhance the gait stability and avoid the additional burden caused by uneven stress. The elastic member 23 realizes energy recycling and reuse to reduce energy consumption. At the same time, the elastic assistance in the kick-off stage improves the kick-off effect, so that the motion characteristics of the bionic ankle joint 100 are closer to the natural state of the human body, and the matching degree of the equipment and the motion characteristics of the human body is improved.

[0036] In some embodiments, the rear sole member 22 is internally formed with an accommodating cavity 221, and the side of the rear sole member 22 facing the front sole member 21 is provided with an opening in communication with the accommodating cavity 221. One end of the front sole member 21 extends into the accommodating cavity 221 through the opening, and the part of the front sole member 21 located in the accommodating cavity 221 is rotationally connected with the inner wall of the rear sole member 22.

[0037] In the embodiment, one end of the front sole member 21 extends into the accommodating cavity 221 of the rear sole member 22 through the opening and is rotationally connected with the inner wall of the accommodating cavity 221. This structure hides the rotation axes of the two members inside the accommodating cavity 221, forming an embedded rotational connection.

[0038] In the gait movement, when the ground impact force acts on the front sole member 21, the part of the front sole member 21 extending into the accommodating cavity 221 can stably rotate around the rotation point of the inner wall. The inner wall of the accommodating cavity 221 limits and guides the rotation track of the front sole member 21, avoiding lateral deviation during rotation. At the same time, the accommodating cavity 221 can protect the connection part of the front sole member 21 and the rear sole member 22, reducing the erosion of the rotating structure by external dust and impurities, ensuring the long-term stability of the rotational connection, and further ensuring the accuracy of the motion transmission.

[0039] Compared with the lateral deviation problem prone to occur in the traditional external rotary connection, the rotary structure embedded in the accommodating cavity 221 is guided and limited by the inner wall, so that the rotary track of the front and rear instep members 22 can be accurately controlled, the motion deviation is avoided, the gait action is more in line with the natural motion law of human body, and especially when walking fast or turning, the unstable shaking of the foot posture can be reduced, and the balance feeling of the user during use is improved.

[0040] In some embodiments, the forefoot member 21 includes an arc-shaped support portion 211 and a hinged portion 212 protruding from the arc-shaped support portion 211, the hinged portion 212 extends into the accommodating cavity 221 through an opening, and the hinged portion 212 is rotatably connected to the inner wall of the rear instep member 22 through a hinge shaft 213.

[0041] The arc-shaped support portion 211 is designed in an arc-shaped curved surface, which is consistent with the natural arc of the metatarsal region of the human forefoot, and can form a surface contact with the ground instead of a point contact when landing, so that the ground impact force is evenly distributed to multiple stress points along the arc-shaped surface, reducing the pressure load of the local area and the wear of the forefoot member 21, while improving the fit with the uneven ground and avoiding the deviation of the foot posture caused by the ground protrusions.

[0042] The outer surface of the hinged portion 212 is gap-fitted with the hinge hole of the inner wall of the rear instep accommodating cavity 221, and the hinge shaft 213 penetrates the hinged portion 212 and the inner wall of the accommodating cavity 221, so that the hinged portion 212 can realize fixed-axis rotation around the hinge shaft 213, avoiding radial deviation during rotation and ensuring that the rotation angle of the forefoot member 21 is highly matched with the motion track of the human foot. Moreover, the hinged portion 212 serves as an intermediary for force transmission between the forefoot member 21 and the rear instep member 22, and can stably conduct the impact force dispersed by the arc-shaped support portion 211 to the rear instep member 22, while reversely transmitting the restoring force of the elastic member 23 to the arc-shaped support portion 211, realizing bidirectional and efficient force transmission and reducing energy loss during transmission.

[0043] The arc-shaped support portion 211 is used to realize the dispersion and transmission of impact force, avoiding component damage caused by local stress concentration; and the precise fit of the hinged portion 212 and the hinge shaft 213 makes the rotary track of the forefoot member 21 more stable, reduces the motion deviation, especially in complex gait scenarios such as going up and down stairs and crossing obstacles, the controllability of foot movement can be improved, and the operation difficulty of the user is reduced.

[0044] Further, the arc-shaped support portion 211 is attached to the physiological arc of the human forefoot, and the hinge portion 212 simulates the rotation structure of the human metatarsophalangeal joint, so that the shape and movement mode of the entire forefoot member 21 are closer to the natural human foot, improving the comfort and adaptability of the user during use. Especially in the application of rehabilitation aids, the structure that conforms to the ergonomic design can reduce the pressure and discomfort on the user's foot, reduce the risk of muscle fatigue or skeletal deformation caused by long-term use, and improve the effect of rehabilitation training.

[0045] In some embodiments, the hinge portion 212 is provided with a first limiting protrusion 214 on the side away from the arc-shaped support portion 211, and the inner wall of the rear foot member 22 is provided with a corresponding limiting plane 223 corresponding to the rotation path of the first limiting protrusion 214, and the limiting plane 223 is used to abut the end face of the first limiting protrusion 214 when the forefoot member 21 rotates to a preset angle relative to the rear foot member 22.

[0046] In this embodiment, the first limiting protrusion 214 can be integrally formed on the side of the hinge portion 212 away from the arc-shaped support portion 211, and the end face thereof is designed as a smooth plane to ensure uniform stress when abutting the limiting plane 223, avoiding local stress concentration. The size (height, width) of the first limiting protrusion 214 is accurately designed according to the preset rotation angle, and can be adjusted to adapt to the foot movement angle requirements of different groups of people (such as adults and children).

[0047] The limiting plane 223 is arranged on the inner wall of the accommodating cavity 221 corresponding to the rotation path of the first limiting protrusion 214, and can abut the end face of the first limiting protrusion 214. When the forefoot member 21 rotates relative to the rear foot member 22 around the hinge shaft 213, the first limiting protrusion 214 on the side of the hinge portion 212 away from the arc-shaped support portion 211 rotates synchronously with the hinge portion 212, and its movement trajectory is accurately constrained by the limiting plane 223 of the inner wall of the rear foot member 22; when the rotation angle reaches the preset value (such as the maximum plantar flexion / dorsal flexion angle of the human foot), the end face of the first limiting protrusion 214 abuts the limiting plane 223 tightly, forming a mechanical hard limit, forcibly stopping the further rotation of the forefoot member 21, avoiding excessive deformation of the elastic member 23, damage to the hinge structure or abnormal gait posture due to excessive rotation angle.

[0048] In this embodiment, the cooperation of the first limiting protrusion 214 and the limiting plane 223 can forcibly constrain the rotation range of the forefoot member 21, avoiding excessive plantar flexion / dorsal flexion of the foot due to sudden impact force (such as stepping on empty, stumbling), reducing the risk of secondary injury to the ankle joint and knee joint of the user. Moreover, through mechanical limiting, the over-deformation of the elastic member 23 (such as permanent deformation caused by the spring exceeding the elastic limit) is avoided, and the abnormal wear of the hinge shaft 213 and the shaft hole due to excessive rotation is prevented, reducing the damage probability of the core components. In addition, the limiting structure can avoid the stress imbalance of the overall device caused by abnormal gait posture, reduce the load of the leg member and the ankle joint base 10, prolong the service life of the bionic ankle joint 100 as a whole, and reduce the maintenance cost and replacement frequency.

[0049] In some embodiments, the rear foot member 22 includes a foot plate 224 and a shell 225, the shell 225 is connected with the foot plate 224 and encloses to form a containing cavity 221, and the two ends of the hinge shaft 213 are fixedly connected with the two opposite inner side walls of the shell 225.

[0050] In this embodiment, the foot plate 224 can be made of high-strength wear-resistant material and directly contacts the ground, which can bear the weight of the human body or the load of the equipment and uniformly transmit the load to the shell 225, avoiding deformation of the shell 225 due to direct stress; at the same time, the bottom of the foot plate 224 can be provided with anti-skid lines and pressure dispersion protrusions, further enhancing the friction force with the ground and improving the gait stability.

[0051] The shell 225 and the foot plate 224 are connected to enclose the containing cavity 221 with better sealing, providing an independent and highly protective movement space for the hinge part 212 of the forefoot member 21; at the same time, the two ends of the hinge shaft 213 are fixed with the two opposite inner side walls of the shell 225, forming a rotation shaft structure with rigid support at both ends, which can avoid bending or deviation of the hinge shaft 213 under stress compared with a single support point, ensuring the coaxiality and stability of the forefoot member 21 rotating around the hinge shaft 213.

[0052] In the gait motion, the ground impact force in the landing stage is transmitted to the shell 225 through the foot plate 224, and the shell 225 uniformly disperses the force to the inner wall of the containing cavity 221 and the hinge shaft 213 through the rigid structure, avoiding local stress concentration; the restoring force of the elastic member 23 in the take-off stage is transmitted to the hinge shaft 213 through the hinge part 212, and the fixed hinge shaft 213 at both ends can stably bear the force, preventing the shaft body from loosening during rotation, further ensuring the continuity of motion transmission and the reliability of the coordinated work of each component in the gait cycle.

[0053] In some embodiments, the foot plate 224 is provided with a boss 2241 on the end surface thereof facing the shell 225, the boss 2241 is provided with a first mounting cavity 2242, the hinge part 212 is provided with a second mounting cavity 2121 communicating with the first mounting cavity 2242, one end of the elastic member 23 is accommodated in the first mounting cavity 2242 and connected with the foot plate 224, and the other end is accommodated in the second mounting cavity 2121 and connected with the hinge part 212.

[0054] The boss 2241 is provided on the end surface of the foot plate 224 facing the shell 225, the height and position thereof are accurately designed according to the installation requirement of the elastic member 23, the first mounting cavity 2242 and the second mounting cavity 2121 of the hinge part 212 are coaxially aligned, the force direction of the elastic member 23 after installation is consistent with the preset deformation direction, and the elastic member 23 is prevented from being damaged due to eccentric loading caused by axis deviation.

[0055] The two ends of the elastic member 23 are accommodated in the first mounting cavity 2242 and the second mounting cavity 2121 respectively, forming an installation state of fixed at both ends and suspended in the middle, when the forefoot member 21 rotates around the hinge shaft 213, the elastic member 23 can be stably stretched or compressed along the axis direction of the mounting cavity, avoiding lateral distortion of the elastic member 23 caused by installation deviation; at the same time, the mounting cavity forms a wrapping protection for the elastic member 23, reducing the influence of external interference on the deformation track of the elastic member 23, ensuring that the elastic member 23 always realizes energy storage and release conversion according to the preset path.

[0056] In the gait cycle, the forefoot member 21 rotates downward in the stance phase, driving the second mounting cavity 2121 away from the first mounting cavity 2242, the elastic member 23 is stretched and stores elastic potential energy in the mounting cavity, and the inner wall of the mounting cavity can limit the excessive stretching of the elastic member 23; in the swing phase, the elastic member 23 releases potential energy, pushes the second mounting cavity 2121 close to the first mounting cavity 2242, and drives the forefoot member 21 to reset.

[0057] In the embodiment, the accurate positioning of the first mounting cavity 2242 and the second mounting cavity 2121 can prevent the elastic member 23 from appearing lateral distortion, axial movement and other problems, ensure that the elastic member 23 always deforms in the preset direction, reduce the early damage of the elastic member 23 caused by improper installation, and prolong the service life of the elastic member 23; at the same time, the wrapping protection of the mounting cavity can reduce the influence of external environment on the performance of the elastic member 23, ensure that the elastic member 23 maintains a stable elastic coefficient for a long time, and avoid the decline of gait stability caused by the performance degradation of the elastic member 23.

[0058] Further, the first mounting cavity 2242 and the second mounting cavity 2121 hide the elastic member 23 inside the foot plate 224 and the hinge part 212, avoiding the structure protrusion caused by the external placement of the elastic member 23, making the forefoot mechanism 20 more simple and compact as a whole, and reducing the risk of collision and interference between the elastic member 23 and the inner wall of the shell 225 and the accommodating cavity 221 in the movement process.

[0059] In some embodiments, the boss 2241 is provided with a second limiting protrusion 2243 at one end thereof facing the hinge portion 212, which is used to abut against the hinge portion 212 when the forefoot member 21 is rotated to a preset angle relative to the rear foot member 22.

[0060] The second limiting protrusion 2243 is provided at one end of the boss 2241 facing the hinge portion 212, and the height and width thereof are accurately designed according to the preset limiting angle, which can form a bidirectional limiting cooperation with the first limiting protrusion 214, avoiding the risk of out-of-control rotation angle when the single limiting structure fails.

[0061] When the forefoot member 21 is rotated relative to the rear foot member 22 around the hinge shaft 213, the hinge portion 212 moves synchronously with the forefoot member 21, and the movement track thereof is real-time constrained by the second limiting protrusion 2243; when the rotation angle reaches another preset value, the end surface of the hinge portion 212 abuts against the second limiting protrusion 2243 closely, forming secondary hard limiting, which cooperates with the original first limiting structure to limit the rotation range of the forefoot member 21 in a more accurate and safer interval.

[0062] In the gait cycle, when the forefoot member 21 is downward rotated in the landing stage, the hinge portion 212 gradually approaches the boss 2241 until abutting against the second limiting protrusion 2243, avoiding excessive forefoot plantar flexion leading to the elastic member 23 exceeding the safe deformation range; when the forefoot member 21 is upward rotated in the take-off stage, the hinge portion 212 moves away from the boss 2241, and the second limiting protrusion 2243 can serve as an auxiliary guide for the rotation track in this process, ensuring the stable movement direction of the hinge portion 212, while forming bidirectional limiting complementation with the first limiting protrusion 214, further guaranteeing the standardization of gait movement and the safety of the equipment.

[0063] In the present embodiment, the double limiting mechanism formed by the second limiting protrusion 2243 and the first limiting protrusion 214 can effectively avoid the safety hazards caused by the failure of single limiting, such as excessive deformation of the elastic member 23, damage of the forefoot mechanism 20, etc.; at the same time, the double limiting can widen the control accuracy of the limiting angle, ensuring that the rotation of the forefoot member 21 is always within the safe range.

[0064] In some embodiments, the bionic ankle joint 100 further comprises a damper 30 arranged between the ankle joint base 10 and the rear foot member 22, the damper 30 comprising a damping body 31 and a piston rod 32 capable of extending and retracting relative to the damping body 31, the damping body 31 being hinged to the ankle joint base 10, and the piston rod 32 being hinged to the rear foot member 22, for extending and retracting relative to the damping body 31 when the rear foot member 22 is stressed, so as to generate damping effect on the rotation of the rear foot member 22.

[0065] The damping body 31 is internally provided with a closed damping cavity filled with damping medium and a throttling structure. When the piston rod 32 is extended or retracted, the damping medium is forced to pass through the throttling hole to generate a pressure difference, thereby forming an adjustable damping force. The plug rod is hingedly connected to the rear instep component 22 at one end and extends into the damping body 31 and contacts the damping medium at the other end, so as to convert the rotating force of the rear instep component 22 into an extension and retraction action, and simultaneously transmit the damping force generated by the damping body 31.

[0066] When the rear instep component 22 is rotated relative to the ankle joint base 10 under the impact of the ground impact force or the gait driving force, the piston rod 32 hingedly connected to the rear instep component 22 is extended or retracted relative to the damping body 31 according to the rotating action; the damping medium (such as hydraulic oil or viscous material) in the damping body 31 generates resistance through the throttling hole or the friction structure, thereby forming a damping force for the extension and retraction of the piston rod 32. The damping force acts on the rear instep component 22 in the opposite direction, thereby slowing down the rotation speed of the rear instep component 22 and avoiding gait impact or posture imbalance caused by excessive rotation.

[0067] During the gait cycle, the rear instep component 22 is quickly rotated downward after landing, and the damper 30 generates a damping force through the retraction of the piston rod 32, thereby buffering the rapid rotation trend caused by the impact of the ground and enabling the instep to stably contact the ground. During the take-off stage, the rear instep component 22 is rotated upward, and the damper 30 generates a damping force through the extension of the piston rod 32, thereby avoiding excessive force caused by excessive rotation speed and, in cooperation with the restoring force of the elastic member 23, achieving a gait rhythm of stable acceleration, uniform force, and slow resetting. This further conforms to the motion characteristics of the natural ankle joint of the human body and improves the continuity of the gait.

[0068] Compared with the buffering mode relying only on the elastic member 23, the damper 30 slows down the rotation speed of the rear instep component 22 through the damping force, thereby avoiding hard impact during landing and rapid acceleration during take-off, and enabling the gait action to be more gentle. Especially in the scenarios of going up and down stairs and uneven road surfaces, the damper 30 can reduce the rapid rotation of the instep caused by sudden changes in the road surface, reduce the stress impact on the ankle and knee joints of the user, improve the comfort of long-term use, and is suitable for people sensitive to impact, such as the elderly and rehabilitation patients.

[0069] In some embodiments, the hinge point of the damping body 31 and the ankle joint base 10 is a first hinge point 101, the hinge point of the piston rod 32 and the rear instep component 22 is a second hinge point 102, the rotating connection point of the front instep component 21 and the rear instep component 22 is a first rotating center 103, and the rotating connection point of the rear instep component 22 and the ankle joint base 10 is a second rotating center 104.

[0070] The second rotation center 104 is located at the connecting edge of the ankle joint base 10 and the rear instep member 22, the first hinge point 101 is located on the side of the ankle joint base 10 away from the second rotation center 104, the second hinge point 102 is located on the side of the rear instep member 22 away from the second rotation center 104, and the line connecting the first hinge point 101, the second hinge point 102, the first rotation center 103 and the second rotation center 104 forms a quadrilateral structure.

[0071] In this embodiment, the second rotation center 104 serves as the core rotation fulcrum of the rear instep member 22 and the ankle joint base 10, and is located at the connecting edge to ensure that the rotation range of the rear instep member 22 conforms to the human ankle movement trajectory; the first hinge point 101 (damping body 31-ankle joint base 10) and the second hinge point 102 (piston rod 32-rear instep member 22) are respectively located on the two sides away from the second rotation center 104, so that the quadrilateral structure forms a force transmission path with lateral force and central rotation.

[0072] When the rear instep member 22 rotates around the second rotation center 104, the second hinge point 102 moves in an arc with it, and pulls or pushes the damping body 31 to rotate around the first hinge point 101 through the piston rod 32. The length and angle of each side of the quadrilateral change in real time with the movement, ensuring that the damping force is always transmitted in the tangent direction opposite to the rotation direction of the rear instep member 22, maximizing the damping speed control effect. At the same time, this layout makes the first rotation center 103 (front instep member 21-rear instep member 22) and the quadrilateral structure form a linkage, so that the front instep member 21 can indirectly adjust the stress state of the damper 30 through the quadrilateral structure when it rotates, realizing the integrated movement of front instep landing buffer, rear instep damping speed control and overall gait coordination, and further fitting the biomechanical characteristics of human foot movement.

[0073] The quadrilateral layout of this embodiment optimizes the positions of each fulcrum, so that the damping force acts on the rear instep member 22 with the optimal force arm. Under the same damping force output, it can achieve stronger speed control effect and reduce the fluctuation of the rotation speed of the rear instep member 22; at the same time, the damping force changes uniformly with the rotation angle, avoiding the discomfort of gait caused by sudden change of damping force, especially in the scene of rapid turning or emergency braking, which can quickly and stably adjust the instep posture and improve the safety of movement.

[0074] Moreover, the quadrilateral structure has geometric stability, which can effectively constrain the movement trajectory of each component and avoid lateral deviation or shaking of the rear instep member 22 and the damper 30 during movement; at the same time, the stress of each fulcrum is evenly dispersed to the ankle joint base 10 and the rear instep member 22 through the quadrilateral structure, reducing local stress concentration and improving the carrying capacity of the overall structure, which is suitable for scenes of bearing large weight or complex road impact.

[0075] The embodiment of the present application also provides a prosthesis, which comprises a leg member and the bionic ankle joint 100 as described above, and the leg member is connected with the ankle joint base 10 at the end away from the rear instep member 22. Since the prosthesis adopts all the technical solutions of all the embodiments of the bionic ankle joint 100 described above, the prosthesis also has all the beneficial effects brought by the technical solutions of the above embodiments, which will not be repeated here.

[0076] The above embodiments of the present application are only examples for clearly illustrating the present application, and are not intended to limit the implementation manners of the present application. Based on the above description, other different forms of changes or variations can be made by those skilled in the art. Here, all the implementation manners cannot be exhausted. Any obvious changes or variations derived from the technical solutions of the present application still fall within the protection scope of the present application.

Claims

1. A bionic ankle joint, characterized in that, include: Ankle joint base for connection to leg components; A foot mechanism, comprising a forefoot component, a rearfoot component, and at least one elastic element, wherein the rearfoot component is rotatably connected to the ankle joint base, the forefoot component is rotatably connected to the rearfoot component, and one end of the elastic element is connected to the rearfoot component and the other end is connected to the forefoot component, for providing elastic restoring force when the forefoot component rotates relative to the rearfoot component; The bionic ankle joint also includes a damper disposed between the ankle joint base and the rearfoot component. The damper includes a damping body and a piston rod that can extend and retract relative to the damping body. The damping body is hinged to the ankle joint base, and the piston rod is hinged to the rearfoot component. The piston rod is used to extend and retract relative to the damping body when the rearfoot component is subjected to force, so as to generate a damping effect on the rotation of the rearfoot component.

2. The bionic ankle joint according to claim 1, characterized in that, The rearfoot component has a cavity inside, and the rearfoot component has an opening on the side facing the forefoot component that communicates with the cavity. One end of the forefoot component extends into the cavity through the opening, and the portion of the forefoot component located in the cavity is rotatably connected to the inner wall of the rearfoot component.

3. The bionic ankle joint according to claim 2, characterized in that, The forefoot component includes an arc-shaped support portion and a hinge portion protruding from the arc-shaped support portion. The hinge portion extends into the receiving cavity through the opening, and the hinge portion is rotatably connected to the inner wall of the rearfoot component through a hinge shaft.

4. The bionic ankle joint according to claim 3, characterized in that, The hinge portion is provided with a first limiting protrusion on the side away from the arc-shaped support portion. The inner wall of the rear foot component is provided with a matching limiting plane corresponding to the rotation path of the first limiting protrusion. The limiting plane is used to abut against the end face of the first limiting protrusion when the forefoot component rotates relative to the rear foot component to a preset angle.

5. The bionic ankle joint according to claim 3, characterized in that, The heel component includes a foot plate and a housing. The housing is connected to the foot plate and encloses the cavity. The two ends of the hinge shaft are fixedly connected to the two opposite inner sidewalls of the housing, respectively.

6. The bionic ankle joint according to claim 5, characterized in that, The foot plate has a boss on its end face facing the housing. The boss has a first mounting cavity. The hinge portion has a second mounting cavity that communicates with the first mounting cavity. One end of the elastic member is housed in the first mounting cavity and connected to the foot plate, and the other end is housed in the second mounting cavity and connected to the hinge portion.

7. The bionic ankle joint according to claim 6, characterized in that, The boss has a second limiting protrusion at one end facing the hinge portion. The second limiting protrusion is used to abut against the hinge portion when the forefoot component rotates relative to the rearfoot component to a preset angle.

8. The bionic ankle joint according to claim 1, characterized in that, The hinge point between the damping body and the ankle joint base is the first hinge point, the hinge point between the piston rod and the rear foot component is the second hinge point, the rotational connection point between the forefoot component and the rear foot component is the first rotation center, and the rotational connection point between the rear foot component and the ankle joint base is the second rotation center. Wherein, the second rotation center is located at the connecting edge of the ankle joint base and the hindfoot component, the first hinge point is located on the side of the ankle joint base away from the second rotation center, the second hinge point is located on the side of the hindfoot component away from the second rotation center, and the line connecting the first hinge point, the second hinge point, the first rotation center and the second rotation center forms a quadrilateral structure.

9. A prosthesis, characterized in that, It includes a leg component and a bionic ankle joint as described in any one of claims 1 to 8, wherein the leg component is connected to the end of the ankle joint base away from the hindfoot component.

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