JPH0330763A - Knee joint in skeleton artificial leg - Google Patents

Abstract

PURPOSE:To make a troublesome operation unnecessary and to make a cross- legged swing possible by taking off a pin hooking between a rotating plate and an upper part of a joint based on an angle-adjusting type fixed cam set on a drum shaft and when a knee is bent larger than a specified angle. CONSTITUTION:A knee joint in a skeleton artificial leg can take a normal walking state for walking by making a hooking pin 11 fitted on a rotating plate 10 placed on the upper face of an upper part 6 of a joint freely-fittable in the follower 12 side vertically fitted on an upper part 6 of the joint and making the follower 12 to slide on a fixed cam 13 of an end of a drum shaft 5 of a knee drum 4 set on a lower part 1 of the joint. In this case, a smooth and safe walking is possible by providing an extending lever 16 on the knee joint 4 and making the release compulsory after the knee is bent. In addition, when sat with one's legs crossed or cross-legged, only by bending this knee joint larger than the max. bending angle for walking, the follower 12 at the upper part 6 side of the joint follows the displacement of the fixed cam 13 to retreat upward the hooking pin 11 and a hooking between the upper part 6 of the joint and the pin 11 of the rotating plate 10 is automatically taken off and the lower limb side can be swung transversely.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a knee joint in a skeletal prosthesis that combines a uniaxial interjoint mechanism and a cross-legged mechanism.

<Prior art> In general, in the knee joint of a skeletal prosthetic leg that is fitted with an exterior member that is a urethane cover that has the same shape and color as a normal limb, a simple brake drum-shaped hollow drum is installed at the upper end of the lower part of the joint. The upper part of the joint is connected to the front end of the drum to form a joint structure, and an elastic band for knee extension is stretched between the front surface of the upper part of the joint and the front surface of the lower leg bone connected to the lower part of the joint. . In this case, conventional knee joint mechanisms of this type were aimed only at bending during walking;
Sit on a chair or on the floor.

I was unable to do the so-called cross-legged swing, which involves rotating your legs in the yellow direction, such as when you sit down on a tatami mat.

<Problems to be Solved by the Invention> For this reason, in recent years, the knee joint has been improved to allow not only forward and backward flexion during walking but also lateral rotation (cross-legged movement) at the request of patients. It's coming. In this case, the rotation mechanism is such that a push button is horizontally protruded from a socket-side outer shell member connected to the upper part of the joint, and faces the core shaft part of the upper joint that fits into the outer shell member attached to the rear end of the push button. The click mechanism is used horizontally to press the locking pin, and this push button is pressed from the outside across the urethane cover each time to release the double engagement between the socket outer shell member and the upper part of the joint.
The lower leg side, which is below the upper part of this joint, is swung laterally. That is, in the conventional cross-legged swinging mechanism, each pushbutton operation is performed manually from the outside, making it cumbersome to handle.

Furthermore, since the extension mechanism for returning the knee from bending during walking is performed using elastic bands disposed on the outer surfaces of the upper and lower parts of the joint, it has the defect of digging into the urethane cover. Also, inside this urethane cover is the elastic band.

The part corresponding to the push button had to be cut a little, making it troublesome to manufacture.

In view of the above-mentioned circumstances, the present invention solves the above-mentioned problems by using an extension lever that is inserted into the prosthetic leg body to restore knee flexion, and by using a cam that automatically disengages the upper part of the joint when the angle exceeds a predetermined original bending angle. The object is to provide a knee joint in a skeletal prosthesis that solves the above problems.

<Means for Solving the Problems> The present invention includes a knee drum having a rear end provided with an extension lever controlled by an elastic mechanism in the lower part of the joint, which is pivotally mounted on the upper end of the lower part of the joint by a drum axis; A support arm for the upper part of the joint is attached to the front part of the knee drum, and a rotary plate for cross-legged sitting is rotatably placed on the upper surface of the upper joint, and the pin engagement between the rotary plate and the upper part of the joint is controlled by the drum. Due to the angle-adjustable fixed cam provided on the shaft, it comes off when the knee is bent over a predetermined angle.

Due to the structure described above, during normal walking, this knee joint is bent forward at a predetermined angle when transitioning from the kicking position to the swing leg, and at the end of the swing leg, the knee joint is folded forward by a predetermined angle. Forced push back allows for extension and smooth walking. In addition, if the seat is bent deeper than the maximum knee flexion during a prescribed walk, the pin-shaped follower that hangs down from the top of the joint will move against the cam surface of the fixed cam at the end of the drum shaft at the bottom of the joint. The driven body moves back the click shaft which is a pin engagement between the upper part of the joint and the rotary plate, and the rotary plate side becomes freely rotatable in the lateral direction.

This means that the lower leg side, which is the lower part of the joint, swings into the groove when the socket side rotating plate is used as a reference. That is, if the knee is bent at a predetermined angle or more, the click axis is automatically disengaged and a so-called cross-legged swing is possible.

<Example> Hereinafter, an example of the present invention will be described based on the drawings.

Reference numeral 1 designates a lower part of the joint that connects the lower leg pipe 2 to the lower part of the joint, and a knee drum in which a brake slit 3, which is inclined upward in the front part, is formed in the supporting pieces 1a protruding from both sides of the rear upper end of the lower part of the joint 1. 4 is supported by a fixed drum shaft 5 passing therethrough, and a support arm 6a protruding from the lower front end of the joint upper part 6 is fitted into a fitting part 4b provided at the front end of the knee drum 4. They are connected through the support shaft 7 to form a knee joint body 8, and a horizontal socket-side cross-legged rotary plate 10 is installed to overlap the upper surface of this joint upper part 6, and is planted in the center of this joint upper part 6. The core shaft 9 of the rotary plate 10 is inserted into the central hole 10a of the rotary plate 10, and a locking pin 11 with a spring lla disposed inside is protruded downward from the peripheral edge of the rotary plate 10.
is a click mechanism that faces onto a pin-type driven body 12 installed at the peripheral edge of the upper joint 6, and the angle of this driven body 12 is adjusted by a tightening shaft 32 provided at the side end of the drum shaft 5. The fixed cam 13 is movable up and down according to the displacement of the cam surface 13a, and constitutes a cross-legged swinging mechanism 14. Further, a bendable extension lever 16 is connected to the lever receiving branch 15 integrally provided at the rear end of the knee drum 4, and the lower end of the extension lever 16 is
The knee joint 20 is connected to one sliding piece with a spring 18 serving as a resilient mechanism mounted on a support tube 17 projecting from the inner lower end of the lower joint 1, and the knee joint 20 as a whole is of a safe walking type.

In this case, the lever part 6 installed on the lower center surface of the upper joint 6
b is the tightening piece portion 4C which becomes the upper part of the slit of the knee drum 4;
contact with. Further, an alignment adjustment means 22 is installed on the upper part of the rotary plate 10. This alignment adjustment means 22 includes a bowl-shaped ring 21 placed on the upper surface of the rotary plate 10.
The curved surface 23a of the lower surface of the annular socket base 23 is overlapped with the curved surface 21a of the socket base 23, and the inside of the ring frame 23b of the socket base 23 is
The alignment of the tapered piece 24 installed in the frame is determined by the amount of insertion of four regulating bolts 25 inserted laterally from the outer periphery on all sides. This tapered piece body 2 installed in the opposite direction
4 is a fixing bolt 26 inserted through the center of the rotating plate 10.
It is screwed onto the nut body 27 disposed on the core shaft 9 of the upper part 6 of the joint passing through, and is tightened and fixed. Further, this tapered piece body 24 has a bearing 2 between the tightening shaft portion 24a and the outer tapered portion 24b.
Even if the outer taper part 2 is fixed to the upper part 6 of the joint with the
4b is configured to be movable as the rotating plate 10 rotates.

Reference numeral 29 denotes a socket into which the stump is inserted, and the socket 29 is integrated by screwing the tip of a mounting bolt 30 inserted through a screw hole 31 drilled in the socket pedestal 23 installed on the lower surface. Further, the angle-adjustable fixed cam 13 is fixed by tightening the end of the tightening shaft 32 that passes through the drum shaft 5 from the opposite side, and by screwing the end of the clamping shaft 32 into contact with the supporting piece 1a. A set screw 33 is provided. This fixed cam 13 is connected to the tightening shaft portion 32.
The separation position (angle) of the locking pin 11 can be freely adjusted by changing the cam displacement in advance by setting the tightening position.

Next, to explain this function, first, when using this knee joint 20, the lower leg vibrator 2 is inserted into the connecting cylinder part 1b of the joint lower part 1, fixed with the tightening screw 34, and the socket attached to the upper surface of the joint upper part 6 is inserted. The thigh socket 29 is fixed to the pedestal 23.

In this state, the stump of the patient is fitted into the socket 29 and set. In this case, the alignment (axial position) is adjusted by appropriately screwing in the regulation bolts 25 inserted into the four sides of the socket pedestal 23, and pressing the tips of the bolts against the tapered surface 24a of the tapered piece body 24. The body 24 is moved to substantially shift the socket pedestal 23 left and right and back and forth to adjust the axial position on the knee joint side. At this time, the bowl-shaped ring 21 at the intermediate position can be shifted and inclined with respect to the curved surface 23a of the socket base 23. Further, the exterior member A of the urethane cover is attached to the entire skeletal prosthesis.

Here, it is sufficient to perform a predetermined walk. That is, when the weight is applied to the knee joint during the transition from the end of the kick-off phase, which is the end of the stance phase, to the swing phase, the joint lower part 1, which is the ground contact side, is used as a reference, and the joint lower part 1 and the knee drum 4 (See FIG. 8). In this case, the knee drum 4, which inclines as it bends, is free to push down the extension lever 16 connected to the support piece 15 at the rear end against the elasticity of the spring 18 attached to the support cylinder 17 on the lower side of the joint. When the foot is moved off the ground, the spring 18 pushes up the extension lever 16 and the knee drum 4 returns to its original position and rotates. That is, it is possible to forcibly and quickly release the leg when shifting to the free leg position.

Also, while walking, if you want to do IL at the specified knee bending position,
When the weight is shifted to the thigh side, the lever part 6b on the lower surface of the joint upper part 6, which has a lever effect, suppresses and turns the tightening piece part 4c, which is the upper part of the slit of the knee drum 4, so that this drum part 4a is pinched and the drum shaft is 5, the brake is quickly applied, and the bent state is maintained. In addition, in the knee flexion range associated with normal walking, even if the driven body 12 hanging down from the joint upper part 6 side slides on the cam surface 13a of the fixed cam 13, it does not reach the predetermined cam displacement position. The locking pin 11 in contact with the driven body 12 has not yet been pushed back into the rotating plate 10, and the rotating plate 10 is still immobile (fixed).

Next, when you want to swing your lower legs to the side when you sit with your legs crossed, etc., bend the upper part 6 of the joint using the drum shaft 5 as a fulcrum from a standing position. by sliding the cam surface 13a of the
°), the cam surface 13a reaches the maximum displacement position a, so the driven body 12 that can slide on the cam surface 13a is pushed up, and the rotating plate 1-0 in contact with it is locked. pin 11
is moved backward against spring lla, and this rotary plate 10
The rotating plate 10 is disengaged and becomes free. After this, if the lower leg side below the joint upper part 6 is turned laterally, the lower leg side is swung laterally and the legs are crossed. This also applies to sitting cross-legged when sitting in a tatami room.

In addition, when returning to the original walking state, rotate the lower leg side in the opposite direction to the above, align the locking pin 11 that has retreated into the rotary plate 10 with the axis of the driven body 12 of the upper joint 6, and then After that, when you stand up with your lower leg on the ground (straighten your knee joint), the driven body 12 moves back from the maximum displacement position a of the cam surface 13a of the fixed cam 13, so the driven body 12 moves upward. The spring pressure of the locking pin 11 pushes out and follows the downward movement, and the tip of the locking pin 11 is pushed into the shaft hole 3 of the upper part 6 of the joint.
5 is inserted into pin engagement, and the upper part of the joint 6 and the rotary plate 10
become one. After this, just walk normally as described above.

<Effects of the Invention> As described above, in the knee joint of the skeletal prosthesis of the present invention, the locking pin attached to the rotary plate disposed on the upper surface of the upper joint can be freely fitted to the driven body side mounted vertically on the upper joint. By making the driven body slide on a fixed cam at the end of the drum shaft of the knee drum provided at the bottom of the joint, a normal gait can be achieved when walking. In this case, an extension lever is provided on the knee drum to forcibly release the knee after it is flexed, allowing smooth and safe walking. Also, when crossing your legs when sitting down or sitting cross-legged, simply bend this knee joint to a greater degree than the maximum bending angle while walking, and the driven body on the upper side of the joint will follow the displacement of the fixed cam and move the locking pin upward. The pin engagement between the upper part of the joint and the rotary plate is automatically released, allowing the lower leg to be swung sideways. When walking again, simply return the lower leg to its original position and rotate it to stand up, and the cam displacement restriction of the locking pin that becomes the click mechanism is released, and the cross-legged swing mechanism is automatically locked.
No complicated operations required. Further, in this case, depending on the setting of the tightening and fixing position of the fixed cam, horizontal swinging is possible even when the knee is deeply bent or shallowly bent. Furthermore, the advantage of the present invention is that it is a cross-legged machine (cleaner) without the conventional push button, and the extension mechanism is built inside the skeleton instead of an externally mounted structure, so there is no digging in of the outer member of the urethane cover. , it can withstand long-term use and is easy to manufacture.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a side view, FIG. 2 is a front view, FIG. 3 is a side view seen from the opposite side, FIG. 4 is a longitudinal sectional side view of the main part, and FIG. Separated slope view, Figure 6 is a side view of the state in use, Figures 7 and 8 are illustrations of normal walking,
FIG. 9 is an explanatory diagram of the locking bottle being separated, and FIG. 10 is an explanatory diagram of the horizontally swinging state. DESCRIPTION OF SYMBOLS 1... Lower part of the joint, 4... Knee drum, 5... Drum shaft, 6... Upper part of the joint, 10... Rotating plate for cross-legged position, 1
DESCRIPTION OF SYMBOLS 1... Locking pin, 12... Follower, 13... Angle adjustable fixed cam, 13a... Cam surface, 16... Extension lever 18... Spring, 19... Sliding pieces. Figure 6 Figure 8

Claims (1)

[Claims] 1. A knee drum whose rear end is provided with an extension lever controlled by an elastic mechanism in the lower part of the joint is pivotally attached to the upper end of the lower part of the joint, and a support arm of the upper part of the joint is attached to the front part of this knee drum. and a rotary plate for cross-legged rotation is placed on the upper surface of the upper part of the joint, and the pin engagement between the rotary plate and the upper part of the joint is caused by an angle-adjustable fixed cam provided on the drum shaft,
A knee joint in a skeletal prosthesis that is characterized by being disengaged when the knee is bent over a predetermined angle.