CN212662036U - Four-bar linkage ankle joint - Google Patents

Abstract

A four-bar ankle joint comprises a first component, a second component, a third component and a fourth component, wherein the first component, the second component, the third component and the fourth component are pivoted to form a four-bar structure, the first component is used for connecting the sole of an artificial limb, and the fourth component is used for connecting the lower leg of the artificial limb; when the first component is in a horizontal state and the four-bar linkage structure is in a standing state of the ankle, an angle is formed between the lower surface of the seat body of the fourth component and the horizontal plane of the base, so that an artificial limb user provided with the ankle joint can swing and stand more smoothly when walking.

Description

Four-bar linkage ankle joint

Technical Field

The utility model relates to an ankle joint used for artificial limb, in particular to an ankle joint structure which can provide all smooth running when swinging, walking and standing.

Background

The ankle joint for a typical prosthetic limb is cumbersome and does not provide a range of motion that mimics a normal foot during walking. During the actual walking process of a human, each foot and ankle goes through the stance and swing phases. During the stance phase, the feet are in contact with the ground and the person's weight is supported on the feet.

During the swing phase, the foot leaves the ground and the entire leg and foot move from a rearward position to a forward position relative to the center of gravity of the body. The stance phase is a phase that starts after the swing phase ends and the heel starts to strike the ground, wherein the feet are lowered to the ground when the body moves forward from the position behind the center of gravity of the human body.

Immediately after the heel strikes the ground, the foot moves from a dorsiflexed position (position with the toe up) to a plantar flexed position, in which the bottom of the foot or shoe remains flat on the ground, which has greater stability throughout its weight. The swing phase then begins after the heel of the other foot strikes the ground, in which the foot leaves the ground and the foot and leg swing forward in preparation for going to the stance phase, bringing the foot in the dorsiflexed position again.

Dorsiflexion is important for normal human movement because the toes must be dorsiflexed to empty the floor. If the foot is not dorsiflexed during the swing phase, it is likely to get stuck on the walking surface and cause the person to fall and fall, possibly causing serious injury.

For amputees, a prosthesis is typically used that is about 3/8 to 1/2 inches shorter than the natural limb in order to provide sufficient ground clearance for the prosthesis during the swing phase. Therefore, the amputee may take an unnatural posture, which may cause problems with the hip, pelvis, knee and back, resulting in a side shift while walking.

In addition, the foot and ankle system of most prostheses is fixed at 90 degrees. When the heel of the prosthetic strikes the ground, the momentum of the human body causes the foot to spin forward to a more stable flat position on the walking surface, but because of the lack of flexibility of the ankle, the human body leans forward. When the center of gravity of the human body crosses the centerline of the foot, the knee is forced to bend to compensate for the unnatural motion. For above-knee amputees, the prosthetic knee joint may become unstable and cause unnecessary or accidental knee flexion and may cause the person to fall.

SUMMERY OF THE UTILITY MODEL

The present invention is directed to a four-bar linkage ankle joint to simulate the natural ankle joint movement during walking, thereby overcoming many of the disadvantages of the prior art.

The utility model provides a four-bar linkage ankle joint, which preferably comprises a first component and a second component, wherein the first component is provided with two first side walls which are symmetrical with each other; the second component is provided with two symmetrical second side walls, and the lower sides of the two second side walls are pivoted with the front side between the two first side walls; the third component is provided with two third side walls which are symmetrical with each other, and the upper side of the second side wall is pivoted with the front side between the third side walls; and a fourth component, which is provided with a connecting rod, wherein different positions of the connecting rod are respectively pivoted on the rear side between the first side walls and the rear side between the third side walls, the first component, the second component, the third component and the fourth component are pivoted to form a four-connecting-rod structure, the first component is used for connecting the sole of the artificial limb, and the fourth component is used for connecting the calf of the artificial limb, therefore, when a user who installs the artificial limb with the ankle joint walks, swings and stands, the walking is smoother and has more natural postures through the natural linkage of the four-connecting-rod structure, and the problems of the buttocks, the pelvis, the knees and the back are avoided.

Preferably, the first member may have a base, and the first sidewall may be integrally formed on an upper surface of the base, whereby the first member can be securely and smoothly mounted on the sole of the prosthetic limb.

Preferably, the second member may be integrally formed in a U shape to form the second sidewall.

Preferably, a gap may be formed between the third sidewalls of the third assembly, and the gap may accommodate the movement of the connecting rod therein.

Preferably, the fourth component may have a seat body, the connecting rod extending eccentrically a length from below the seat body, the seat body being configured to connect to the lower leg portion of the prosthetic.

Preferably, a buffer component is arranged under the seat body of the fourth component corresponding to the position of the connecting rod, and the buffer component protrudes out of the lower surface of the seat body, so that when the foot sole impacts the ground or the ankle joint is in a standing state due to walking, the buffer component can provide a buffer effect between the third component and the fourth component, noise generated by excessive impact force is avoided, and discomfort of a user is avoided.

Preferably, the ankle joint of the present invention forms an angle between the lower surface of the seat body of the fourth component and the horizontal plane of the seat body when the first component is in the horizontal state and the four-bar linkage structure is in the standing state of the ankle, so that the user can lift the foot more easily and more easily in the next stage.

Preferably, when the first assembly is in a horizontal state and the four-bar linkage structure is in a standing state of the ankle, an angle between a lower surface of the seat body of the fourth assembly and a horizontal plane of the base is 3 °.

The utility model provides an aforementioned four-bar linkage ankle joint can borrow and close by natural connecting rod interlock and provide swing, walking and all very smooth-going effect when standing to have more natural posture when the walking, in order to avoid buttock, pelvis, knee and back to go wrong.

Drawings

FIG. 1 is a schematic perspective view showing the overall structure of a four-bar linkage ankle joint of the present invention;

FIG. 2 is an exploded perspective view showing the combination of the main components of the four-bar linkage ankle joint of the present invention;

FIG. 3 is a schematic plan view showing the overall structure of the four-bar linkage ankle joint of the present invention;

FIG. 4 is a schematic view showing the four-bar ankle joint of the present invention used in combination with the calf portion and the sole portion of an artificial limb; and

fig. 5 is a simple schematic diagram showing a four-bar linkage structure formed by the ankle joint of the present invention.

Description of the reference numerals

1 first Assembly

10: base

11 first side wall

111 first pivot hole

2 second Assembly

21 second side wall

211 second pivot hole

3 third Assembly

31 third side wall

311 third pivoting hole

32: notch

4 the fourth component

41: seat body

42 connecting rod

421 the fourth lower pivot hole

422 the fourth upper pivot hole

43 buffer assembly

44 screw hole

5A is the pivot

5B cap head

6, artificial limb shank part

7, the bottom of the artificial limb foot

Angle of theta

Detailed Description

The embodiments of the present invention will be described in more detail with reference to the drawings and the reference numerals, so that those skilled in the art can read the description to implement the embodiments.

As shown in fig. 1 to 3, the present invention provides a four-bar ankle joint, which preferably comprises: a first component 1, a second component 2, a third component 3 and a fourth component 4; the first to fourth members are preferably made of aluminum alloy metal and are pivotally connected to form a four-bar linkage.

Wherein, the first component 1 is integrally formed with a flat base 10 with a proper thickness, the two opposite sides of the upper surface of the base 10 form first sidewalls 11 extending upward with a proper height and being symmetrical to each other, a pair of first pivot holes 111 is correspondingly arranged on the front side straight lines of the two first sidewalls 11, and another pair of first pivot holes 111 is correspondingly arranged on the rear side straight lines of the two first sidewalls 11, the first component 1 can be firmly and stably installed on the bottom 7 of the prosthetic foot by the base 10 (as shown in fig. 4).

The second member 2 is formed to have two second side walls 21 symmetrical to each other; preferably, the second assembly 2 may be integrally formed in a U shape to form the two second side walls 21, a pair of second pivot holes 211 is linearly and correspondingly formed on the upper sides of the two second side walls 21, and another pair of second pivot holes 211 is linearly and correspondingly formed on the lower sides of the two second side walls 21. The second member 2 can rotate relative to the first member 1 in this state by passing a pivot shaft 5A through a pair of first pivot holes 111 on the front side of the first member 1 and a pair of second pivot holes 211 on the lower side of the second member 2 to pivot the lower end of the second member 2 on the front side between the two first side walls 11 of the first member 1, and passing the pivot shaft 5A through the first pivot holes 111 and then combining a cap 5B to fix the pivot shaft 5A.

The third component 3 is integrally formed with two third side walls 31 which are symmetrical to each other; more specifically, a gap 32 is formed between two third sidewalls 31 on the rear side of the third component 3, the two third sidewalls 31 extend downward from the third component 3, the upper end of the second component 2 is pivoted to the front side between the two third sidewalls 31 of the third component 3 by passing another pivot 5A through a pair of third pivot holes 311 on the front side of the third component 3 and a pair of second pivot holes 211 on the upper side of the second component 2, and the pivot 5A passes through the third pivot holes 311 and then is combined with a cap 5B to fix the pivot 5A, in which state, the third component 3 can rotate relative to the second component 2.

The fourth component 4 is integrally formed with a seat 41, and a link 42 with a suitable length extends downward from an eccentric position below the seat 41, and different positions of the link 42 are respectively used for pivotally connecting the rear side between the first side walls 11 of the first component 1 and the rear side between the third side walls 31 of the third component 3. More specifically, the connecting rod 42 is provided with a fourth lower pivot hole 421 and a fourth upper pivot hole 422 passing through transversely respectively at the upper and lower sides thereof, and the upper side of the fourth component 4 is pivoted at the rear side between the two third side walls 31 of the third component 3 by passing another pivot 5A through the pair of third pivot holes 311 at the rear side of the third component 3 and the fourth upper pivot hole 422 at the upper side of the fourth component 4; another pivot 5A is further inserted through the pair of first pivot holes 111 at the rear side of the first side wall 11 of the first component 1 and the fourth lower pivot hole 421 of the connecting rod 42, so as to pivot the lower end of the connecting rod 42 to the first component 1, and the connecting rod 42 is accommodated in the notch 32 of the third component 3; the pivot 5A is connected to a cap 5B after completing the pivotal connection between the link 42 and the first and third modules 1 and 3 to fix the pivot 5A, and in this state, the fourth module 4 can rotate relative to the first and third modules 1 and 3 through the link 42.

In addition, the utility model can also arrange a buffer component 43 under the seat body 41 of the fourth component 4 relative to the position of the connecting rod 42, and make the buffer component 43 protrude out of the lower surface of the seat body 41; more specifically, a slot may be formed on the lower surface of the base 41, the buffer member 43 may be formed in a rod shape by using an elastic PU material, and the rod-shaped buffer member 43 is inserted into the slot to fix the buffer member 43 to the base 41. On the other hand, a fixing base having a screw hole 44 can be formed on the upper surface of the base body 41, and a bolt as the artificial limb shank 6 can be locked into the screw hole 44 to connect the artificial limb shank 6 to the ankle joint of the present invention (as shown in fig. 4).

The ankle joint of the present invention formed by the components shown in fig. 1 to 3 constitutes a four-bar linkage structure as shown in fig. 5. The first component 1 is used for connecting the bottom part 7 of the artificial limb foot, and the fourth component 4 is used for connecting the shank 6 of the artificial limb, therefore, when a user who installs the artificial limb with the ankle joint walks, swings and stands, the walking is smoother through the natural linkage of the four-bar structure, and the artificial limb has a more natural posture, so that the problems of the hip, the pelvis, the knee and the back can be avoided. When the sole of the foot hits the ground or the ankle is in a standing state due to walking, the buffer member 43 absorbs the force between the third member 3 and the fourth member 4, thereby preventing excessive impact from generating noise and preventing the user from feeling uncomfortable.

On the other hand, in order to make it easier and more labor-saving for the user to lift the foot or to lift the foot in the next stage when walking in the standing state, the ankle joint of the present invention is designed such that when the first assembly 1 is in the horizontal state and the four-bar linkage structure is in the standing state of the ankle, an angle is formed between the lower surface of the seat body 41 of the fourth assembly 4 and the horizontal plane of the base 10, and the angle is preferably 3 ° (as shown in fig. 3).

The utility model provides an aforementioned four-bar linkage ankle joint can borrow to close by natural connecting rod interlock and provide swing, walking and all very smooth-going effect when standing (as shown in fig. 4) to have more natural posture when the walking, can avoid buttock, pelvis, knee and back to go wrong.

The foregoing is illustrative of the preferred embodiments of the present invention and is not intended to limit the invention in any way, and therefore any modifications or variations of the invention that fall within the spirit of the invention are intended to be included within the scope of the invention.

Claims (8)

1. A four-bar ankle joint, comprising:

a first assembly having two first sidewalls symmetrical to each other;

the second component is provided with two symmetrical second side walls, and the lower sides of the two second side walls are pivoted with the front side between the two first side walls;

the third component is provided with two third side walls which are symmetrical with each other, and the upper side of the second side wall is pivoted with the front side between the third side walls; and

a fourth component having a connecting rod, different positions of the connecting rod are respectively pivoted on the rear side between the first side walls and the rear side between the third side walls,

the first assembly, the second assembly, the third assembly and the fourth assembly are pivoted to form a four-bar linkage structure, the first assembly is used for connecting the foot bottom of the artificial limb, and the fourth assembly is used for connecting the shank of the artificial limb.

2. The four-bar ankle joint according to claim 1, wherein the first member has a base, and the first sidewall is integrally formed on an upper surface of the base.

3. The four-bar ankle joint according to claim 1 or 2, wherein the second member is integrally formed in a U-shape to form the second side wall.

4. The four-bar ankle joint of claim 3, wherein a gap is formed between the third sidewalls of the third element, the gap accommodating movement of the bar therethrough.

5. The four-bar ankle joint of claim 4, wherein the fourth component has a seat, the connecting rod extending eccentrically a length from below the seat, the seat for connecting to the lower leg of the prosthetic.

6. The four-bar ankle joint according to claim 5, wherein a cushion is provided under the seat at a position opposite to the position of the connecting rods, and the cushion protrudes from under the seat.

7. The four-bar linkage ankle joint of claim 6, wherein an angle is formed between the lower surface of the base of the fourth member and the horizontal plane of the base when the first member is in a horizontal position and the four-bar linkage is in a standing position on the ankle.

8. The four-bar ankle joint according to claim 7, wherein the angle is 3^°。

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