Prosthetic leg with knee braking function
First Claim
1. A prosthetic limb comprising a knee joint, a joint upper member located above said knee joint and a joint lower member located below said knee joint and both the joint upper member and joint lower member being pivotably connected to one another about said knee joint such that the limb can be bent about said knee joint;
- a foot attached to the joint lower member;
wherein said joint lower member includes a component which comprises part of said knee joint and a main body part connected to said component by a connection and said component moves only several mm or less in stroke, or several degrees or less in a pivotal angle in comparison with the bending motion of the main body partsaid prosthetic limb having the following constitutional features X and Y in order to brake the bending motion of said knee flexibly,X. a hydraulic brake circuit for producing a braking force with respect to the bending motion of the knee by flow resistance generated when a working fluid passes through a throttle said hydraulic brake circuit comprises said throttle which generates flow resistance, and a switch valve which switches the throttling function of the throttle between effective state and ineffective state, andY. sensing control means for detecting which part of the foot attached to said prosthetic limb the weight of the wearer is imposed on and generating a detection signal to control the switch valve in said hydraulic brake circuit in accordance with the detection signal; and
said sensing control means has the following features y1 and y2,y1. a link mechanism for connecting said component and said main body part to each other in said joint lower member and having an instantaneous center between a toe and a heel of said foot of said prosthetic limb, wherein a first link in said link mechanism is an operating member to switch the switch valve; and
y2. motion of said first link constituting said link mechanism moves said switch valve to switch the throttling function of said throttle between effective state and ineffective state.
1 Assignment
0 Petitions
Accused Products
Abstract
There is provided a prosthetic limb having a flexible knee brake function, which is designed such that it can be mechanically detected which part of the foot the load of the wearer is imposed on. In a thigh prosthetic limb (10), a joint upper member (12) including a knee plate (120) and a joint lower member (14) including a base bracket (22) integral with the frame (140) are operated to bend the knee. In the housing member (24), there are provided not only a knee axis but also a hydraulic brake circuit. There is a link mechanism (50) which allows a small relative motion between the housing member (24) and the base bracket (22) on the main body part side. The link mechanism (50) has an instantaneous center between the toe and the heel part of the prosthetic limb. This instantaneous center serves as a sensing point and detects which part of the foot the load of the wearer is imposed on by distinguishing a first case in which the wearer'"'"'s load is imposed on the heel and a second case in which the wearer'"'"'s load is imposed on the toe. Based on the detection result made by the link mechanism (50), the hydraulic brake circuit is controlled so that a flexible knee braking operation can be made.
48 Citations
15 Claims
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1. A prosthetic limb comprising a knee joint, a joint upper member located above said knee joint and a joint lower member located below said knee joint and both the joint upper member and joint lower member being pivotably connected to one another about said knee joint such that the limb can be bent about said knee joint;
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a foot attached to the joint lower member; wherein said joint lower member includes a component which comprises part of said knee joint and a main body part connected to said component by a connection and said component moves only several mm or less in stroke, or several degrees or less in a pivotal angle in comparison with the bending motion of the main body part said prosthetic limb having the following constitutional features X and Y in order to brake the bending motion of said knee flexibly, X. a hydraulic brake circuit for producing a braking force with respect to the bending motion of the knee by flow resistance generated when a working fluid passes through a throttle said hydraulic brake circuit comprises said throttle which generates flow resistance, and a switch valve which switches the throttling function of the throttle between effective state and ineffective state, and Y. sensing control means for detecting which part of the foot attached to said prosthetic limb the weight of the wearer is imposed on and generating a detection signal to control the switch valve in said hydraulic brake circuit in accordance with the detection signal; and said sensing control means has the following features y1 and y2, y1. a link mechanism for connecting said component and said main body part to each other in said joint lower member and having an instantaneous center between a toe and a heel of said foot of said prosthetic limb, wherein a first link in said link mechanism is an operating member to switch the switch valve; and y2. motion of said first link constituting said link mechanism moves said switch valve to switch the throttling function of said throttle between effective state and ineffective state. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
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Specification