JP2540184B2 - Knee break prevention device for thigh prosthesis - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a prosthesis of a femoral amputator, and more particularly to a femoral prosthesis having a function capable of reliably preventing knee bending that tends to occur during the walking process.

(Prior Art) FIG. 7 shows changes in posture of the right half of the body when a healthy person is walking in order. (A) heel, (b)
Is a knee, (c) is a crotch, (d) is a neck, (e) is a lower leg,
(F) shows the mutual relationship of each part of the thigh during each walking period.

FIG. 8 shows an example of a general femoral prosthesis of the type using an air cylinder (g) (see Japanese Examined Patent Publication No. 52-47638). Figure 9 shows the walking phases of this type of thigh prosthesis in the upward direction,
The piston (h) position of the air cylinder is shown below in a corresponding relationship.

In this type of thigh prosthesis, the lower leg (e) under the knee (b)
Since it becomes one kind of pendulum in the swing phase, it compensates for the action of muscle by utilizing the flow resistance and compressed air reaction force obtained by the air cylinder (g). In the Japanese Patent Publication, due to the internal structure of the air cylinder (g), the swing-up of the heel (a) at the time of leaving the bed in the swing phase is suppressed, and the lower leg (e) following this is suppressed.
The starting point is lightened and the impact is dampened by braking in the latter period. In the final stance phase, the upper leg (f) and the lower leg (e) are abutted by the stopper (i) at the stroke end to prevent knee bending.

FIG. 10 shows an example of a femoral prosthesis of the kind in which the knee has a braking function. 10 (a) and (b) show the disassembled lower leg (e) and thigh (f), and FIGS. 10 (c) and (d) show the standing phase and swing phase of both parts. Show. In the free leg phase, the friction braking force is relaxed, and in the stance phase, the braking function acts only when the weight is under certain balance to prevent knee bending.

(Problems to be Solved by the Invention) In any of the above-described conventional thigh prostheses, a stopper or a weight is applied only in a state where the weight is leaned forward in the stance phase and a balance is maintained with the help of the wedge effect of the ankle. The brake acts to prevent knee bending. If the weight is not well balanced before or after that, the knee-bending prevention effect cannot be obtained. For example, 9th
During the transition from the 3rd to 4th swing phase from the left in the figure to the stance phase, at the time of trying to land, the knee breaks due to irregularities in the floor, etc., even though the stopper has not hit yet. At that time, since the pressure in the piston lower chamber (j) is low with respect to the downward movement of the piston in the raised position, sufficient knee bending resistance cannot be obtained, and knee bending occurs. It is unstable when standing, because it only puts weight on the frame.

Even in the conventional technique shown in FIG. 10, when the center of gravity shifts and the weight is not sufficiently applied, the braking force is insufficient and the knee bending that is about to actually occur does not exhibit the same satisfactory effect.

The present invention has been made in view of the above-mentioned problems of the conventional art, and an object of the present invention is to provide a femoral prosthesis capable of reliably preventing knee bending during transition from the swing phase to the stance phase. .

Another object of the present invention is to provide a femoral prosthesis capable of cushioning the lower leg frame portion when it is swung up or swung out.

(Means for Solving Problems) The invention according to claim 1 for achieving the above object is
The thigh frame part and the crus frame part are pivotally connected by a knee axis, and the thigh frame part and the crus frame part are expanded and contracted by changing the relative angle between the thigh frame part and the crus frame part to extend in the stance phase. In the thigh artificial leg provided with the cylinder as described above, the knee shaft is provided with a brake unit for controlling the rotation of the knee shaft, the brake unit is connected to the energy storage actuating unit for operating the brake unit, the piston upper chamber of the cylinder, The accumulator and the piston lower chamber of the cylinder are connected by a circulation path that allows only the flow of air in this order, and the air in the piston upper chamber passes through the circulation path during the transition from the free leg phase to the stance phase. The femoral prosthesis is characterized in that the brake portion is actuated by being circulated in the energy storage actuating body to actuate the energy storage actuating body to prevent knee bending.

In the invention according to claim 2, the brake part of the invention of claim 1 comprises a pair of upper and lower brake shoes that sandwich the knee shaft from above and below, and a return spring that urges the pair of upper and lower brake shoes in the opening direction. At the same time, the accumulator is composed of a rubber tube that contracts due to the inflow of air, and one of the rubber tube and the brake shoe is connected by a wire, and the pair of upper and lower brake shoes is contracted by the contraction of the rubber tube. It is configured to be closed.

(Operation) In the invention according to claim 1, even if knee bending occurs in a state where the lower leg frame portion extends and the piston is above the air cylinder in order to shift from the swing phase to the stance phase, at this time, Since the air in the upper chamber of the piston is compressed and sent into the energy storage actuating body, the energy storage actuating body operates and the braking force acts on the brake portion of the knee shaft, so that knee bending is prevented.

The air of increasing pressure in the energy storage actuating body gradually leaks into the lower chamber of the piston, and the braking force disappears after a certain period of time.

Therefore, the braking force can be obtained for a certain period of time without adding weight during the stance phase, and the knee bending prevention effect is exerted.

At the same time, the amount of rise of the heel at the time of leaving the bed is suppressed, the resistance at the time of swinging out the lower leg frame portion is absorbed by the addition of the energy storage actuating body, and the last impact is alleviated as compared with the conventional function.

These series of most desirable operations are automatically performed according to the wearer's willingness to walk independently of a separate control source and control device.

According to the invention of claim 2, the invention of claim 1 can be easily implemented in a small size and a light weight.

(Example) Hereinafter, the present invention will be specifically described in detail with reference to FIGS.

FIG. 1 is a vertical sectional front view of a femoral prosthesis according to the present invention, showing a standing state of a lower leg frame portion, FIG. 2 is a side view thereof, and FIG. 3 is a plan view thereof.

In the thigh prosthesis of this embodiment, the bracket of the thigh frame portion (1) attached to the stump of the thigh amputee and the crus frame portion (2) are pivotally supported by the knee portion (3) to be jointly connected. Both parts can be folded back, but a rubber stopper (4) (see FIG. 2) is provided between the two parts on the opposite side so as not to bend forward due to the contact. The knee shaft (3) is fixed to the side of the thigh frame portion (1) in this example.

Both parts have an interlocking system consisting of an knee cylinder (3) and an air cylinder (5) that expands and contracts according to the bending angle,
In this example, the cylinder (6) is the lower leg frame (2).
A rod (8) mounted vertically in the cavity of the and extending upward from its piston (7) is connected to the thigh frame part (1) via a link (9). The internal structure of the piston (7) will be described later. The air cylinder (5) may be changed to another mounting type as shown in FIG.

A brake unit (10) is provided on the knee shaft (3). In the brake part (10) of this example, a brake disc (11) is attached and fixed on the knee shaft (3). A lower brake shoe (12) is attached to the lower leg frame (2) side so as to sandwich it, and an upper brake shoe (13) is pivotally supported by a pin (14) so as to be movable above. The brake shoe (13) is a return spring (1) stretched between the brake shoe (12) and the lower brake shoe (12).
By 5), it retreats upward and releases the braking action due to the engagement with the brake disc (11).

In order to perform a brake operation by pulling down the upper brake shoe (13) and engaging the brake disk (11), a force accumulator (16) made of a rubber tube or the like is provided in the cavity of the lower leg frame portion (2), (17) (18) penetrates the lower brake shoe (12) and connects to the movable upper brake shoe (13). The accumulator (16) has only to have a characteristic of shortening the length by accumulating the amount of received air. For example, the state shown in FIG. 4 (a) bulges due to the reception of air as shown in FIG. 4 (b). A rubber tube that shrinks in length can be used.

Then, as an air flow path between the accumulator (16) and the piston upper chamber (19) and the piston lower chamber (20) of the air cylinder (5), the accumulation is performed from the piston upper chamber (19) through the check valve (21). A distribution path (22) is provided to reach the force actuator (16),
Variable accumulator (23), check valve (2)
One-way flow path (2) to the piston lower chamber (20) via (4)
5), and further, from the piston lower chamber (20) to the variable throttle valve (26) provided in the piston (7) and the check valve (27) to the piston upper chamber (19), the one-way flow path ( 28) is provided. The details of this path (28) provided in the piston are shown in FIG. 5, but this path (28) may be an external pipe outside the cylinder (6).

In the device of the present invention having the above configuration, when the lower leg frame portion (2) is swung out from the raised position, the piston (7) rises in the cylinder (6) as it extends, and the check valve (27). Is a closed valve, but the check valve (21) is opened, and the air in the piston upper chamber (19) flows into the force-storing actuating body (16). The flow rate is adjusted by the throttle valve (26) so that appropriate buffering is performed.
The air that flows into and accumulates in the energy storage effector (16) shortens the energy storage effector (16) as it accumulates, so the wire (17) is pulled down by the amount of contraction and the upper brake shoe (13) is lowered. Generates a braking force by pressing on the brake disc (11). Therefore, knee fractures will not occur before and after landing.

In the latter half of the stance phase, the accumulated air in the energy storage actuating body (16) opens the check valve (24) and gradually flows into the piston lower chamber (20) at a flow rate limited by the throttle valve (23), and As the pressure in (16) drops, the upper brake shoe (13) is gradually restored by the spring (15) and the braking force is lost. The braking timing is adjusted by the throttle valve (23).

Furthermore, when the legs get out of bed and the heel goes up and bends,
The piston (7) descends in the cylinder (6), and the air in the piston lower chamber (20) opens the check valve (27) and moves to the piston upper chamber (19), so the heel rises lightly and its flow rate increases. Is restricted by the throttle valve (26), and the amount of heel rise is suppressed to a predetermined amount by the adjustment.

FIG. 6 shows a modified portion of the above-described embodiment of the present invention. The related equivalent portions are designated by the same reference numerals and the description thereof will be omitted. In this embodiment, an air cylinder (30) incorporating a return spring (29) is used instead of the rubber tube. The knee axis brake part (10) can also be changed to other well-known brake mechanisms.

(Effects of the Invention) According to the present invention, unexpected knee bending during the transition from the swing phase to the stance phase is reliably prevented and is stable, and the lower leg frame portion is swung up, and the impact is mitigated when straightening out. It is possible to provide a femoral prosthesis capable of satisfactorily exhibiting the exercise function that should be provided.

Therefore, by preventing the knee fracture of the femoral prosthesis that occurs when the femoral prosthesis wearer walks on rough terrain, etc., it is possible to prevent the femoral prosthesis wearer from falling due to knee fracture, and to provide a safe and comfortable thigh prosthesis. be able to.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional front view of a femoral prosthesis according to an embodiment of the present invention in a standing state of a lower leg frame, FIG. 2 is a side view thereof, FIG. 3 is a plan view thereof, and FIG. FIG. 4 (b) is a side view of the force actuating rubber tube before air reception, FIG. 4 (b) is a side view thereof after air reception, FIG. 5 is a sectional view showing a configuration of a passage in the piston, and FIG. The schematic diagram which shows the structure of the deformation | transformation part of an example, FIG. 7 is a diagram which shows the change of a walking posture of a healthy person in order from the left, FIG. 8 is a side view of one example of a femoral prosthesis using an air cylinder of a prior art, FIG. 9 is a diagram showing the changes in each phase of walking of the thigh prosthesis in the upward direction and the condition of the cylinder in the downward direction in order from the left, and FIG. 10 (a) shows the knee axis brake type of the prior art. A perspective view of the lower leg of the thigh prosthesis, FIG. 10 (b) is a perspective view of the thigh, and FIG. 10 (c) is a combination thereof. Side view in stance phase of FIG. 10 (d) is a side view in the swing phase. (1) …… Thigh frame part, (2) …… Lower thigh frame part, (3) …… Knee axis, (4) …… Stopper, (5) ……
Air cylinder, (6) …… Cylinder, (7) …… Piston, (8) …… Rod, (9) …… Link, (10)…
… Knee Axis Brake, (11) …… Brake Disc, (1
2) …… Lower brake shoe, (13) …… Upper brake shoe, (14) …… Pin, (15) (29) …… Return spring,
(16) …… Accumulator, (17) (18) …… Wire, (1
9) …… Piston upper chamber, (20) …… Piston lower chamber, (2
1) (24) (27) …… Check valve, (23) (26) …… Throttle valve, (22) (25) (28) …… Path, (30) …… Air cylinder, (a)… … Heels, (b) …… Knees, (c) ……
Crotch, (d) ... neck, (e) ... lower leg, (f) ... thigh, (g) ... air cylinder, (h) ... piston,
(I) …… Stopper, (j) …… Lower chamber.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kunio Amamori 2-25-204 Kariguchidai, Tarumi-ku, Kobe-shi, Hyogo (72) Inventor Hironori Matsuda 1264-16 Okubo, Okubo-cho, Akashi-shi, Hyogo (72) Inventor Oku Hidehisa 2-2-16-208 Nishishinmachi, Akashi-shi, Hyogo (72) Inventor Akio Nakagawa 4-5-13 Umenoki, Itami-shi, Hyogo (72) Inventor Ichiro Kitayama 18-3-, Deai, Tamazu-cho, Nishi-ku, Kobe-shi, Hyogo 303 (72) Inventor Katsuhiko Yoshida 933-27 Yoneda, Yoneda-cho, Takasago-shi, Hyogo Prefecture (72) Inventor Masaru Takeda 2-1-1-15 Otaki, Tarumi-ku, Kobe-shi, Hyogo Prefecture

Claims (2)

(57) [Claims] 1. A thigh frame part and a crus frame part are pivotally connected by a knee axis, and the thigh frame part and the crus frame part are expanded and contracted by changing the relative angle of the both thigh frame parts in a stance phase. In a femoral prosthesis in which a cylinder is installed so as to be in an extended state, a knee shaft is provided with a brake unit for controlling the rotation of the knee shaft, and a storage unit for operating the brake unit is connected to the brake unit. The piston upper chamber, the accumulator and the piston lower chamber of the cylinder are connected by a circulation path that allows only the flow of air in this order, and the air in the piston upper chamber is changed during the transition from the free-leg phase to the stance phase. A femoral prosthesis characterized in that the brake portion is actuated to prevent knee breakage by circulating the fluid through the circulation path into the energy storage actuating body and operating the energy storage actuating body. 2. The brake unit comprises a pair of upper and lower brake shoes that sandwich the knee shaft from above and below, and a return spring that urges the pair of upper and lower brake shoes in an opening direction, and the accumulator operates by the inflow of air. 2. A shrinkable rubber tube, wherein one of the rubber tube and the brake shoe is connected by a wire, and the pair of upper and lower brake shoes are closed by contraction of the rubber tube. Thigh prosthesis.