Bionic ankle joint and artificial limb

Abstract

The invention discloses a bionic ankle joint and an artificial limb, the bionic ankle joint comprises an ankle joint base and a sole mechanism, and the ankle joint base is used for being connected with a leg component; the sole mechanism comprises a front sole component, a rear sole component and at least one elastic piece, the rear sole component is rotationally connected with the ankle joint base, the front sole component is rotationally connected with the rear sole component, one end of the elastic piece is connected with the rear sole component, and the other end of the elastic piece is connected with the front sole component; the elastic component is used for providing elastic restoring force when the front sole component rotates relative to the rear sole component. The sole fitting degree is improved through multi-joint linkage, the gait stability is enhanced, the additional burden caused by uneven stress is avoided, energy recycling is achieved through the elastic piece, energy consumption is reduced, meanwhile, the pedaling effect is improved through elastic assistance in the pedaling stage, the motion characteristic of the bionic ankle joint is closer to the natural state of the human body, and the mechanical performance of the bionic ankle joint is improved. And the matching degree of equipment and human motion characteristics is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of prostheses, and in particular to a bionic ankle joint and a prosthesis. Background Art

[0002] In the field of rehabilitation assistive devices and bionic robotics, bionic ankle design is crucial for matching devices with human motion characteristics and improving stability and flexibility. As the crucial link between the lower leg and foot, the ankle joint not only bears the body's weight but also rotates at multiple angles during various motions, such as walking, running, and jumping. Its biomechanical properties also provide appropriate cushioning to reduce damage to the limbs from ground impact forces while ensuring a natural and smooth gait.

[0003] Existing bionic ankle joints often utilize a monolithic sole structure. This design often struggles to achieve adaptive conformity on uneven surfaces, prone to single-point contact, resulting in reduced gait stability and potentially placing additional strain on the user due to uneven force distribution. Furthermore, during compression, most of the energy in these monolithic soles is directly dissipated, preventing effective energy recovery and reuse. Furthermore, during push-off, sufficient energy is not released to provide active assistance, resulting in high energy consumption throughout the gait process and poor push-off performance. This makes it difficult to match the natural motion characteristics and energy conversion efficiency of the human ankle joint. Summary of the Invention

[0004] The main purpose of the present invention is to propose a bionic ankle joint and prosthesis, aiming to solve the technical problems of the existing bionic ankle joint caused by the integral sole design, such as poor ground adhesion, inability to recycle energy, high gait energy consumption and poor push-off effect.

[0005] To achieve the above objectives, the present invention provides a bionic ankle joint, comprising: An ankle joint base, the ankle joint base is used to connect with the leg member; The sole mechanism includes a forefoot member, a rear foot member and at least one elastic member, the rear foot member is rotatably connected to the ankle joint base, the forefoot member is rotatably connected to the rear foot member, one end of the elastic member is connected to the rear foot member, and the other end is connected to the forefoot member, for providing elastic restoring force when the forefoot member rotates relative to the rear foot member.

[0006] In some embodiments, a accommodating cavity is formed inside the rear sole member, and an opening connected to the accommodating cavity is provided on the side of the rear sole member facing the forefoot member. One end of the forefoot member extends into the accommodating cavity through the opening, and the part of the forefoot member located in the accommodating cavity is rotatably connected to the inner wall of the rear sole member.

[0007] In some embodiments, the forefoot component includes an arcuate support portion and a hinge portion protruding from the arcuate support portion, the hinge portion extends into the accommodating cavity through the opening, and the hinge portion is rotatably connected to the inner wall of the rear foot component through a hinge shaft.

[0008] In some embodiments, a first limiting protrusion is provided on the side of the hinge portion away from the arc-shaped support portion, and a corresponding limiting plane is provided on the inner wall of the rear sole component corresponding to the rotation path of the first limiting protrusion, and the limiting plane is used to abut against the end face of the first limiting protrusion when the forefoot component rotates to a preset angle relative to the rear sole component.

[0009] In some embodiments, the rear sole component includes a foot plate and a shell, the shell is connected to the foot plate and encloses the accommodating cavity, and the two ends of the hinge shaft are respectively fixedly connected to the two opposite inner walls of the shell.

[0010] In some embodiments, the end surface of the foot plate facing the shell is provided with a boss, the boss is provided with a first mounting cavity, the hinge portion is provided with a second mounting cavity connected to the first mounting cavity, one end of the elastic member is accommodated in the first mounting cavity and connected to the foot plate, and the other end is accommodated in the second mounting cavity and connected to the hinge portion.

[0011] In some embodiments, a second limiting protrusion is provided on one end of the boss toward the hinge portion, and the second limiting protrusion is used to abut against the hinge portion when the forefoot component rotates to a preset angle relative to the rear foot component.

[0012] In some embodiments, the bionic ankle joint also includes a damper, which is arranged between the ankle joint base and the rear sole component. The damper includes a damping body and a piston rod that can be extended and retracted relative to the damping body. The damping body is hinged to the ankle joint base, and the piston rod is hinged to the rear sole component, and is used to extend and retract relative to the damping body when the rear sole component is subjected to force, so as to produce a damping effect on the rotation of the rear sole component.

[0013] In some embodiments, the hinge point between the damping body and the ankle joint base is a first hinge point, the hinge point between the piston rod and the rear sole member is a second hinge point, the rotation connection point between the forefoot member and the rear sole member is a first rotation center, and the rotation connection point between the rear sole member and the ankle joint base is a second rotation center; Among them, the second rotation center is located at the connecting edge of the ankle joint base and the rear sole 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 rear sole component away from the second rotation center, and the lines connecting the first hinge point, the second hinge point, the first rotation center and the second rotation center form a quadrilateral structure.

[0014] The present application also provides a prosthesis, comprising a leg component and a bionic ankle joint, wherein the leg component is connected to one end of the ankle joint base away from the rear sole component.

[0015] The bionic ankle joint provided by the present application is connected to the leg member through the ankle joint base. The rear sole member of the sole mechanism is rotatably connected to the ankle joint base, and the forefoot member is rotatably connected to the rear sole member, and the two are connected by elastic members to form a multi-joint linkage structure. When contacting uneven ground, the forefoot member rotates independently relative to the rear sole member, and the rear sole member rotates independently relative to the ankle joint base. Through the coordinated movement of multiple joints, the sole of the foot and the ground are adaptively fitted to avoid single-point contact. During the gait compression phase, the forefoot member rotates relative to the rear sole member to deform the elastic member and store energy to reduce dissipation. During the push-off phase, the elastic member releases energy and provides active assistance to the forefoot member through elastic restoring force to assist in completing the push-off action. The present application improves the fit of the sole of the foot through multi-joint linkage, enhances gait stability, avoids the additional burden caused by uneven force, and realizes energy recovery and reuse of the elastic member to reduce energy consumption. At the same time, the elastic assistance during the push-off phase improves the push-off effect, making the motion characteristics of the bionic ankle joint closer to the natural state of the human body and improving the matching degree between the device and the human body's motion characteristics. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic structural diagram of an embodiment of a bionic ankle joint of the present invention; Figure 2 This is a disassembled schematic diagram of an embodiment of a bionic ankle joint of the present invention; Figure 3 Schematic cross-section of an embodiment of a bionic ankle joint according to the present invention.

[0017] The purpose, features and advantages of the present invention will be further described with reference to the accompanying drawings and in conjunction with the embodiments. DETAILED DESCRIPTION

[0018] The following will be combined with the accompanying drawings to clearly and completely describe the solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of the present invention.

[0019] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the various components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0020] It should also be noted that when an element is referred to as being "fixed on" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or there may be an intermediate element.

[0021] In addition, the descriptions of "first", "second", etc. in the present invention are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0022] Please refer to Figures 1 to 3 The embodiment of the present application proposes a bionic ankle joint 100, including an ankle joint base 10 and a sole mechanism 20, the ankle joint base 10 is used to connect with the leg member; the sole mechanism 20 includes a forefoot member 21, a rear foot member 22 and at least one elastic member 23, the rear foot member 22 is rotatably connected to the ankle joint base 10, and the forefoot member 21 is rotatably connected to the rear foot member 22, one end of the elastic member 23 is connected to the rear foot member 22, and the other end is connected to the forefoot member 21, for providing elastic restoring force when the forefoot member 21 rotates relative to the rear foot member 22.

[0023] Among them, the ankle joint base 10 can be connected to the leg structure in a detachable or fixed manner through bolt connection, snap fixation or customized interface design, ensuring the coaxiality and stability of the entire bionic ankle joint 100 and the leg structure, and avoiding deviation or loosening during movement.

[0024] The forefoot member 21 features a curved contact surface design, simulating the physiological curve of the human forefoot. This allows for multiple points of contact with uneven surfaces during walking, running, and other activities, reducing gait instability caused by single-point contact and improving the device's adaptability in unstructured environments. The forefoot member 21 rotates relative to the rearfoot member 22, triggering the energy storage and release of the elastic element 23. Its rotation angle also provides real-time feedback on road slope and hardness, providing fundamental data support for gait control.

[0025] One end of the rear sole component 22 is rotatably connected to the ankle joint base 10, and the other end is rotatably connected to the forefoot component 21, realizing plantar flexion, dorsiflexion and slight rollover movements of the ankle joint, matching the multi-degree-of-freedom movement requirements of the human ankle joint.

[0026] The elastic part 23 can be made of an alloy spring with a high elastic coefficient, a silicone material or a memory foam component. When the forefoot component 21 is compressed and rotated, it absorbs the ground impact energy through its own deformation, reduces the transmission of the ground impact force to the legs, and reduces the damage to the user's limbs. It is especially suitable for users with weak lower limb function in rehabilitation assistive device scenarios.

[0027] Unlike traditional, integrated soles that dissipate energy, the elastic element 23 stores the energy absorbed during landing as elastic potential energy, actively releasing it during push-off. This provides restoring force to the forefoot member 21, reducing energy consumption in the leg drive mechanism while increasing push-off force, making the gait more similar to the human body's natural motion. When the sole of the foot contacts an inclined surface, the relative rotation angle between the forefoot member 21 and the rearfoot member 22 changes, and the degree of deformation of the elastic element 23 adjusts accordingly. This differentiated elastic restoring force corrects the sole's posture in real time, ensuring stable contact between the foot and the ground, improving the device's ability to navigate unstructured environments such as sloped and gravel roads.

[0028] In the actual gait cycle, during the landing phase, the ground impact force first acts on the forefoot component 21, pushing the forefoot component 21 to rotate downward relative to the rearfoot component 22 around the rotating connection. At this time, the elastic component 23 is stretched or compressed, absorbing the impact energy and converting it into elastic potential energy, thereby preventing the impact force from being directly transmitted to the leg; during the push-off phase, the elastic component 23 releases the stored elastic potential energy, generating an elastic restoring force to drive the forefoot component 21 to reset, providing active assistance for the foot to push off the ground, restoring the energy conversion process of the human body's natural gait, and realizing the integrated movement of buffering, energy storage, and assistance.

[0029] Compared with the single-point contact problem that is prone to occur in the integral sole of the prior art, the bionic ankle joint 100 provided in the present application is connected to the leg component through the ankle joint base 10. The rear sole component 22 in the sole mechanism 20 is rotatably connected to the ankle joint base 10, and the forefoot component 21 is rotatably connected to the rear sole component 22, and the two are connected by an elastic member 23 to form a multi-joint linkage structure. When contacting uneven ground, the forefoot component 21 rotates independently relative to the rear sole component 22, and the rear sole component 22 rotates independently relative to the ankle joint base 10. Through the coordinated movement of multiple joints, the sole of the foot and the ground are adaptively fitted to avoid single-point contact. During the gait compression phase, the forefoot component 21 rotates relative to the rear sole component 22 to deform the elastic member 23 to store energy to reduce dissipation. During the push-off phase, the elastic member 23 releases energy and provides active assistance to the forefoot component 21 through elastic recovery force to assist in completing the push-off action.

[0030] This application improves the fit of the sole of the foot through multi-joint linkage, enhances gait stability, and avoids the extra burden caused by uneven force. The elastic part 23 realizes energy recovery and reuse to reduce energy consumption. At the same time, the elastic assist in the push-off stage improves the push-off effect, making the movement characteristics of the bionic ankle joint 100 closer to the natural state of the human body, and improving the matching degree between the equipment and the movement characteristics of the human body.

[0031] In some embodiments, a accommodating cavity 221 is formed inside the rear sole member 22, and an opening connected to the accommodating cavity 221 is provided on the side of the rear sole member 22 facing the forefoot member 21. One end of the forefoot member 21 extends into the accommodating cavity 221 through the opening, and the part of the forefoot member 21 located in the accommodating cavity 221 is rotatably connected to the inner wall of the rear sole member 22.

[0032] In this embodiment, one end of the forefoot component 21 extends into the accommodating cavity 221 of the rear foot component 22 through the opening and forms a rotational connection with the inner wall of the accommodating cavity 221. This structure allows the rotation axes of the two to be hidden inside the accommodating cavity 221, forming an embedded rotation fit.

[0033] During gait movement, when the ground impact force acts on the forefoot component 21, the part thereof 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 forms a limiting guide for the rotation trajectory of the forefoot component 21, thereby avoiding lateral deviation during the rotation process. At the same time, the accommodating cavity 221 can form a protection for the connection part between the forefoot component 21 and the rear foot component 22, thereby reducing the erosion of the rotating structure by external dust and impurities, ensuring the long-term stability of the rotation coordination, and further ensuring the accuracy of motion transmission.

[0034] Compared with the lateral offset problem that is prone to occur in traditional external rotating connections, the rotating structure embedded in the accommodating cavity 221 can accurately control the rotation trajectory of the front and rear sole components 22 through inner wall guidance and limitation, avoid movement deviation, and make the gait movement more in line with the natural movement laws of the human body. Especially when walking or turning quickly, it can reduce the unstable shaking of the foot posture and improve the user's sense of balance when using it.

[0035] In some embodiments, the forefoot component 21 includes an arcuate support portion 211 and a hinge portion 212 protruding from the arcuate support portion 211. The hinge portion 212 extends into the accommodating cavity 221 through the opening, and the hinge portion 212 is rotatably connected to the inner wall of the rear foot component 22 through a hinge shaft 213.

[0036] Among them, the arc-shaped support part 211 adopts an arc-shaped curved surface design, which is consistent with the natural curvature of the metatarsal area of ​​the forefoot of the human body. When landing, it can form surface contact with the ground rather than point contact, and evenly disperse the ground impact force to multiple force points along the arc-shaped surface, reducing the pressure load in the local area, reducing the wear of the forefoot component 21, and at the same time improving the fit with uneven ground, avoiding the deviation of the foot posture caused by the protrusion of the ground.

[0037] The outer surface of the hinge portion 212 forms a clearance fit with the hinge hole on the inner wall of the rear sole accommodating chamber 221. The hinge shaft 213 penetrates the hinge portion 212 and the inner wall of the accommodating chamber 221, allowing the hinge portion 212 to rotate around the hinge shaft 213, avoiding radial deviation during rotation and ensuring that the rotation angle of the forefoot member 21 is highly compatible with the movement trajectory of the human foot. Furthermore, the hinge portion 212 acts as a force transmission medium between the forefoot member 21 and the rear sole member 22, stably transmitting the impact force dispersed by the arcuate support portion 211 to the rear sole member 22, while simultaneously transmitting the restoring force of the elastic member 23 in the opposite direction to the arcuate support portion 211, achieving efficient bidirectional force transmission and reducing energy loss during the transmission process.

[0038] This embodiment achieves dispersed transmission of impact force through the arc-shaped support portion 211, avoiding damage to components caused by local stress concentration; at the same time, the precise coordination between the hinge portion 212 and the hinge shaft 213 makes the rotation trajectory of the forefoot component 21 more stable and reduces movement deviation, especially in complex gait scenarios such as going up and down stairs and crossing obstacles, which can improve the controllability of foot movement and reduce the difficulty of operation for users.

[0039] Furthermore, the curved support portion 211 conforms to the physiological curvature of the human forefoot, and the hinged portion 212 simulates the rotational structure of the metatarsophalangeal joint of the human foot. This makes the shape and movement of the entire forefoot member 21 more similar to the natural human foot, improving user comfort and adaptability. In particular, in rehabilitation assistive device applications, the more ergonomically designed structure can reduce pressure and discomfort on the user's foot, reduce the risk of muscle fatigue or bone deformation caused by long-term use, and enhance the effectiveness of rehabilitation training.

[0040] In some embodiments, a first limiting protrusion 214 is provided on the side of the hinge portion 212 away from the arc-shaped support portion 211, and a corresponding limiting plane 223 is provided on the inner wall of the rear sole component 22 corresponding to the rotation path of the first limiting protrusion 214. The limiting plane 223 is used to abut against the end face of the first limiting protrusion 214 when the forefoot component 21 rotates to a preset angle relative to the rear sole component 22.

[0041] In this embodiment, the first limiting protrusion 214 is integrally formed on the side of the hinge portion 212 away from the arcuate support portion 211. Its end surface features a smooth, flat design, ensuring uniform force when abutting against the limiting surface 223 and avoiding localized stress concentration. The dimensions (height and width) of the first limiting protrusion 214 are precisely designed based on the preset rotation angle, allowing the protrusion's size to be adjusted to accommodate the foot movement angle requirements of different groups (e.g., adults and children).

[0042] The limiting plane 223 is located on the inner wall of the accommodating cavity 221 at a position corresponding to the rotation path of the first limiting protrusion 214, and can abut and fit with the end surface of the first limiting protrusion 214. When the forefoot member 21 rotates relative to the rearfoot member 22 about the hinge axis 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 motion trajectory is precisely constrained by the limiting plane 223 on the inner wall of the rearfoot member 22. When the rotation angle reaches a preset value (e.g., matching the maximum plantar flexion / dorsiflexion angle of the human foot), the end surface of the first limiting protrusion 214 tightly abuts the limiting plane 223, forming a mechanical hard limit, forcibly stopping further rotation of the forefoot member 21, and preventing excessive deformation of the elastic member 23, damage to the hinge structure, or abnormal gait posture caused by excessive rotation angle.

[0043] In this embodiment, the cooperation between the first limiting protrusion 214 and the limiting plane 223 can forcibly constrain the rotation range of the forefoot component 21, avoiding excessive plantar flexion / dorsiflexion of the foot due to sudden impact force (such as stepping on air or tripping), and reducing the risk of secondary injury to the user's ankle and knee joints. Moreover, mechanical limiting can prevent excessive deformation of the elastic member 23 (such as permanent deformation caused by the spring exceeding the elastic limit), while preventing abnormal wear of the hinge shaft 213 and the shaft hole due to excessive rotation, thereby reducing the probability of damage to the core components. In addition, the limiting structure can avoid the imbalance of force on the entire device caused by abnormal gait posture, reduce the load on the leg components and the ankle joint base 10, and extend the service life of the bionic ankle joint 100 as a whole, reducing maintenance costs and replacement frequency.

[0044] In some embodiments, the rear sole member 22 includes a foot plate 224 and a shell 225 . The shell 225 is connected to the foot plate 224 and encloses a receiving cavity 221 . Both ends of the hinge shaft 213 are fixedly connected to two opposite inner side walls of the shell 225 .

[0045] In this embodiment, the foot plate 224 can be made of high-strength wear-resistant material, directly in contact with the ground, can bear the weight of the human body or the load of equipment, and evenly transfer the load to the shell 225 to prevent the shell 225 from being deformed due to direct force; at the same time, the bottom of the foot plate 224 can be provided with anti-slip grooves and pressure-dispersing protrusions to further enhance the friction with the ground and improve gait stability.

[0046] The shell 225 is connected to the foot plate 224 to form a more closed accommodating cavity 221, providing an independent and highly protective movement space for the hinge portion 212 of the forefoot component 21; at the same time, the two ends of the hinge shaft 213 are fixed to the two opposite inner walls of the shell 225, forming a rotating shaft structure with rigid support at both ends. Compared with a single support point, the hinge shaft 213 can be prevented from bending or deflecting when subjected to force, thereby ensuring the coaxiality and stability of the forefoot component 21 when rotating around the hinge shaft 213.

[0047] During gait movement, the ground impact force in the landing phase is transmitted to the shell 225 through the foot plate 224. The shell 225 distributes the force evenly to the inner wall of the accommodating cavity 221 and the hinge shaft 213 through the rigid structure to avoid local force concentration; in the push-off phase, the restoring force of the elastic member 23 is transmitted to the hinge shaft 213 through the hinge part 212. The hinge shaft 213 fixed at both ends can stably bear the action of the force, prevent the shaft from loosening during the rotation process, further ensure the continuity of motion transmission, and ensure the reliability of the coordinated work of various components in the gait cycle.

[0048] In some embodiments, a boss 2241 is provided on the end face of the foot plate 224 facing the shell 225, the boss 2241 is provided with a first mounting cavity 2242, the hinge portion 212 is provided with a second mounting cavity 2121 connected to the first mounting cavity 2242, one end of the elastic member 23 is accommodated in the first mounting cavity 2242 and connected to the foot plate 224, and the other end is accommodated in the second mounting cavity 2121 and connected to the hinge portion 212.

[0049] Among them, the boss 2241 is protruded from the end face of the foot plate 224 facing the shell 225, and its height and position are precisely designed according to the installation requirements of the elastic part 23, so that the first installation cavity 2242 and the second installation cavity 2121 of the hinge part 212 can be kept coaxially aligned, ensuring that the force direction of the elastic part 23 after installation is consistent with the preset deformation direction, thereby avoiding damage to the elastic part 23 due to axial offset.

[0050] The two ends of the elastic member 23 are respectively accommodated in the first installation cavity 2242 and the second installation cavity 2121, forming an installation state in which the two ends are fixed and the middle is suspended. When the forefoot component 21 rotates around the hinge shaft 213, the elastic member 23 can be stably stretched or compressed along the axis direction of the installation cavity to avoid lateral distortion of the elastic member 23 due to installation offset; at the same time, the installation cavity forms a wrapping protection for the elastic member 23, reducing the influence of external interference on the deformation trajectory of the elastic member 23, and ensuring that the elastic member 23 always realizes energy storage and release conversion according to the preset path.

[0051] During the gait cycle, during the landing phase, the forefoot component 21 rotates downward, driving the second mounting cavity 2121 away from the first mounting cavity 2242, and the elastic member 23 is stretched and stores elastic potential energy in the mounting cavity. The inner wall of the mounting cavity can limit the excessive stretching of the elastic member 23; during the push-off phase, the elastic member 23 releases the potential energy, pushing the second mounting cavity 2121 close to the first mounting cavity 2242, driving the forefoot component 21 to reset.

[0052] In this embodiment, the precise positioning of the first mounting cavity 2242 and the second mounting cavity 2121 can avoid lateral distortion, axial movement and other problems of the elastic part 23, ensure that the elastic part 23 always deforms along the preset direction, reduce early damage to the elastic part 23 due to improper installation, and extend the service life of the elastic part 23; at the same time, the wrapping protection of the mounting cavity can reduce the impact of the external environment on the performance of the elastic part 23, ensure that the elastic part 23 maintains a stable elastic coefficient for a long time, and avoid the decline in gait stability due to performance degradation of the elastic part 23.

[0053] Furthermore, the first installation cavity 2242 and the second installation cavity 2121 hide the elastic member 23 inside the foot plate 224 and the hinge part 212, avoiding the structural protrusion caused by the external placement of the elastic member 23, making the sole mechanism 20 more simple and compact as a whole, and reducing the risk of collision and interference between the elastic member 23 and the shell 225 and the inner wall of the accommodating cavity 221 during movement.

[0054] In some embodiments, a second limiting protrusion 2243 is provided on one end of the boss 2241 toward the hinge portion 212 , and the second limiting protrusion 2243 is used to abut against the hinge portion 212 when the forefoot member 21 rotates to a preset angle relative to the rear foot member 22 .

[0055] Among them, the second limiting protrusion 2243 is arranged at one end of the boss 2241 facing the hinge part 212. Its height and width are precisely designed according to the preset limiting angle, and can form a two-way limiting cooperation with the first limiting protrusion 214 to avoid the risk of uncontrolled rotation angle when a single limiting structure fails.

[0056] When the front sole component 21 rotates relative to the rear sole component 22 around the hinge shaft 213, the hinge part 212 moves synchronously with the front sole component 21, and its movement trajectory is constrained in real time by the second limiting protrusion 2243; when the rotation angle reaches another preset value, the end face of the hinge part 212 is tightly abutted against the second limiting protrusion 2243, forming a secondary hard limit, which cooperates with the original first limiting structure to limit the rotation range of the forefoot component 21 to a more precise and safer range.

[0057] During the gait cycle, when the forefoot component 21 rotates downward during the landing phase, the hinge part 212 gradually approaches the boss 2241 until it abuts against the second limiting protrusion 2243, preventing excessive plantar flexion of the forefoot from causing the elastic member 23 to exceed the safe deformation range; when the forefoot component 21 rotates upward during the push-off phase, the hinge part 212 moves away from the boss 2241. During this process, the second limiting protrusion 2243 can serve as an auxiliary guide for the rotation trajectory, ensuring that the movement direction of the hinge part 212 is stable, and at the same time forming a two-way limiting complement with the first limiting protrusion 214, further ensuring the standardization of gait movement and the safety of the equipment.

[0058] In this embodiment, the double limiting mechanism formed by the second limiting protrusion 2243 and the first limiting protrusion 214 can effectively avoid safety hazards caused by the failure of a single limit, such as excessive deformation of the elastic member 23, damage to the sole 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 component 21 is always within a safe range.

[0059] In some embodiments, the bionic ankle joint 100 also includes a damper 30, which is arranged between the ankle joint base 10 and the rear sole component 22. The damper 30 includes a damping body 31 and a piston rod 32 that can be extended and retracted relative to the damping body 31. The damping body 31 is hinged to the ankle joint base 10, and the piston rod 32 is hinged to the rear sole component 22, and is used to extend and retract relative to the damping body 31 when the rear sole component 22 is subjected to force, so as to produce a damping effect on the rotation of the rear sole component 22.

[0060] The damping body 31 houses a sealed damping chamber filled with a damping medium and a throttling mechanism. When the piston rod 32 extends or retracts, the damping medium is forced through the throttling mechanism, generating a pressure differential that creates an adjustable damping force. One end of the piston rod is hinged to the rear foot member 22, while the other end extends into the damping body 31, where it comes into contact with the damping medium. This converts the rotational force of the rear foot member 22 into an extension and retraction motion, while simultaneously transmitting the damping force generated by the damping body 31.

[0061] When the rear sole member 22 is rotated relative to the ankle joint base 10 by the impact force of the ground or the gait driving force, the piston rod 32 hinged to the rear sole member 22 expands and contracts relative to the damping body 31 with the rotation movement; the damping medium (such as hydraulic oil, viscous material) inside the damping body 31 generates resistance through the throttle hole or friction structure, forming a damping force on the expansion and contraction of the piston rod 32, and the damping force acts in the opposite direction to the rear sole member 22, slowing down its rotation speed, thereby avoiding gait impact or posture imbalance caused by excessive rotation.

[0062] During the gait cycle, after the landing phase, the sole component 22 rotates downward rapidly, and the damper 30 generates a damping force through the contraction of the piston rod 32, which cushions the rapid rotation trend caused by the impact of the ground and allows the sole of the foot to contact the ground steadily; after the push-off phase, the sole component 22 rotates upward, and the damper 30 uses the damping force when the piston rod 32 is extended to avoid excessive force caused by excessive rotation speed. At the same time, it cooperates with the restoring force of the elastic member 23 to achieve a gait rhythm of smooth acceleration, uniform force, and slow reset, further fitting the movement characteristics of the natural ankle joint of the human body and improving gait continuity.

[0063] Compared with the buffering method that only relies on the elastic part 23, the damper 30 slows down the rotation speed of the rear foot component 22 through the damping force, avoiding hard impact when landing and sudden acceleration when pushing off, making the gait movement smoother; especially in scenes such as going up and down stairs, uneven roads, etc., it can reduce the rapid rotation of the sole of the foot caused by sudden changes in the road surface, reduce the force impact on the user's ankle and knee joints, and improve the comfort of long-term use. It is suitable for people who are sensitive to impact, such as the elderly and rehabilitation patients.

[0064] In some embodiments, the hinge point between the damping body 31 and the ankle joint base 10 is a first hinge point 101, the hinge point between the piston rod 32 and the rear sole member 22 is a second hinge point 102, the rotation connection point between the forefoot member 21 and the rear sole member 22 is a first rotation center 103, and the rotation connection point between the rear sole member 22 and the ankle joint base 10 is a second rotation center 104; Among them, the second rotation center 104 is located at the connecting edge of the ankle joint base 10 and the rear sole component 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 sole component 22 away from the second rotation center 104, and the lines connecting the first hinge point 101, the second hinge point 102, the first rotation center 103 and the second rotation center 104 form a quadrilateral structure.

[0065] In this embodiment, the second rotation center 104 serves as the core rotation fulcrum between the rear sole component 22 and the ankle joint base 10, and is located at the connection edge to ensure that the rotation range of the rear sole component 22 conforms to the movement trajectory of the human ankle joint; the first hinge point 101 (damping body 31-ankle joint base 10) and the second hinge point 102 (piston rod 32-rear sole component 22) are respectively located on both sides away from the second rotation center 104, so that the quadrilateral structure forms a force transmission path with external force and central rotation.

[0066] When the rearfoot member 22 rotates about the second rotation center 104, the second hinge point 102 follows its arc-shaped motion, pulling or pushing the damper body 31 about the first hinge point 101 via the piston rod 32. The length and angle of each side of the quadrilateral change in real time with this motion, ensuring that the damping force is always transmitted in a tangential direction opposite to the rotation direction of the rearfoot member 22, maximizing the damping and speed control effect. Simultaneously, this layout creates a linkage between the first rotation center 103 (forefoot member 21-rearfoot member 22) and the quadrilateral structure. Rotation of the forefoot member 21 allows the force applied to the damper 30 to be indirectly adjusted through the quadrilateral structure, achieving an integrated motion that combines forefoot impact cushioning, rearfoot damping and speed control, and overall gait coordination, further aligning with the biomechanical characteristics of human foot movement.

[0067] The quadrilateral layout of this embodiment optimizes the position of each fulcrum so that the damping force acts on the rear sole component 22 with the optimal lever arm. Under the same damping force output, a stronger speed control effect can be achieved, and the fluctuation of the rotation speed of the rear sole component 22 can be reduced. At the same time, the damping force changes evenly with the rotation angle, avoiding gait discomfort caused by sudden changes in the damping force, especially in fast turning or emergency braking scenarios, which can quickly stabilize the foot posture and improve sports safety.

[0068] Moreover, the quadrilateral structure has geometric stability, which can effectively constrain the movement trajectory of each component and prevent the rear foot component 22 and the damper 30 from lateral displacement or shaking during movement; at the same time, the force of each support point is evenly distributed to the ankle joint base 10 and the rear foot component 22 through the quadrilateral structure, reducing local stress concentration and improving the bearing capacity of the overall structure, which is suitable for scenarios withstanding heavy weight or complex road impact.

[0069] The present application also provides a prosthesis comprising a leg member and the bionic ankle joint 100 described above, wherein the leg member is connected to the end of the ankle joint base 10 remote from the rear foot member 22. Because the prosthesis utilizes all technical solutions of all embodiments of the bionic ankle joint 100 described above, the prosthesis of the present invention also possesses at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be detailed here.

[0070] The above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the embodiments of the present invention. Those skilled in the art will appreciate that other variations or modifications based on the above description are possible. It is not possible to enumerate all embodiments here. Any obvious variations or modifications arising from the technical solutions of the present invention remain within the scope of protection of the present invention.

Claims

1. A bionic ankle joint, characterized in that: include: An ankle joint base, the ankle joint base is used to connect with the leg member; The sole mechanism includes a forefoot member, a rear foot member and at least one elastic member, the rear foot member is rotatably connected to the ankle joint base, the forefoot member is rotatably connected to the rear foot member, one end of the elastic member is connected to the rear foot member, and the other end is connected to the forefoot member, for providing elastic restoring force when the forefoot member rotates relative to the rear foot member.

2. The bionic ankle joint according to claim 1, characterized in that: A accommodating cavity is formed inside the rear sole member, and an opening connected to the accommodating cavity is provided on the side of the rear sole member facing the forefoot member. One end of the forefoot member extends into the accommodating cavity through the opening, and the part of the forefoot member located in the accommodating cavity is rotatably connected to the inner wall of the rear sole member.

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 accommodating cavity through the opening, and the hinge portion is rotatably connected to the inner wall of the rear foot component through a hinge shaft.

4. The bionic ankle joint according to claim 3, characterized in that: A first limiting protrusion is provided on the side of the hinge portion away from the arc-shaped supporting portion, and a corresponding limiting plane is provided on the inner wall of the rear sole component 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 front sole component rotates to a preset angle relative to the rear sole component.

5. The bionic ankle joint according to claim 3, characterized in that: The rear sole component includes a foot plate and a shell, the shell is connected to the foot plate and encloses the accommodating cavity, and the two ends of the hinge shaft are respectively fixedly connected to the two opposite inner side walls of the shell.

6. The bionic ankle joint according to claim 5, characterized in that: The end surface of the foot plate facing the shell is provided with a boss, the boss is provided with a first mounting cavity, the hinge portion is provided with a second mounting cavity connected to the first mounting cavity, one end of the elastic member is accommodated in the first mounting cavity and connected to the foot plate, and the other end is accommodated in the second mounting cavity and connected to the hinge portion.

7. The bionic ankle joint according to claim 6, characterized in that: A second limiting protrusion is protruded from one end of the boss toward the hinge portion, and the second limiting protrusion is used to abut against the hinge portion when the forefoot component rotates to a preset angle relative to the rear foot component.

8. The bionic ankle joint according to any one of claims 1 to 7, characterized in that: The bionic ankle joint also includes a damper, which is arranged between the ankle joint base and the rear sole component. The damper includes a damping body and a piston rod that can be extended and retracted relative to the damping body. The damping body is hinged to the ankle joint base, and the piston rod is hinged to the rear sole component, and is used to extend and retract relative to the damping body when the rear sole component is subjected to force, so as to produce a damping effect on the rotation of the rear sole component.

9. The bionic ankle joint according to claim 8, characterized in that: The hinge point between the damping body and the ankle joint base is a first hinge point, the hinge point between the piston rod and the rear sole member is a second hinge point, the rotation connection point between the forefoot member and the rear sole member is a first rotation center, and the rotation connection point between the rear sole member and the ankle joint base is a second rotation center; Among them, the second rotation center is located at the connecting edge of the ankle joint base and the rear sole 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 rear sole component away from the second rotation center, and the lines connecting the first hinge point, the second hinge point, the first rotation center and the second rotation center form a quadrilateral structure.

10. A prosthesis, characterized in that: The bionic ankle joint comprises a leg member and the bionic ankle joint according to any one of claims 1 to 9, wherein the leg member is connected to an end of the ankle joint base away from the rear sole member.

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