ARTIFICIAL KNEE JOINT WITH A PUSH ROD BIASED TO ROTATE A PROSTHETIC LOWER LEG RAPIDLY TO ALIGN WITH A RESIDUAL THIGH
An artificial knee joint includes a joint seat, a support frame, a hydraulic device, a push rod, and a biasing member. The joint seat has a joint body and a rotatable member connected pivotally to the joint body and connected fixedly to a residual thigh. The support frame is connected rotatably to the joint body, and is connected fixedly to a prosthetic lower leg. The push rod is movable relative to the joint body between an extended position, where a free end of the rotatable member is spaced apart from the joint body to align the lower leg with the thigh, and a retracted position, where the free end of the rotatable member abuts against the joint body. The biasing member biases the push rod to the extended position.
1. Field of the Invention
This invention relates to an artificial knee joint, and more particularly to an artificial knee joint that includes a push rod biased to rotate a prosthetic lower leg rapidly to align with a residual thigh.
2. Description of the Related Art
Referring to
When the thigh 8 is raised to flex the joint 200, as shown in
The object of this invention is to provide an artificial knee joint that includes a push rod biased to rotate a prosthetic lower leg rapidly to align with a residual thigh.
According to this invention, an artificial knee joint includes a joint seat, a support frame, a hydraulic device, a push rod, and a biasing member. The joint seat has a joint body and a rotatable member connected pivotally to the joint body and connected fixedly to a residual thigh of a prosthesis wearer. The support frame is connected rotatably to the joint body, and is connected fixedly to a prosthetic lower leg. The push rod is disposed movably within the joint body, and is movable between an extended position, where the push rod projects from the joint body and where a free end of the rotatable member is spaced apart from the joint body to align the lower leg with the thigh, and a retracted position, where the push rod is retracted into the joint body and where the free end of the rotatable member abuts against the joint body. The biasing member biases the push rod to the extended position so that the free end of the rotatable member turns away from the joint body.
BRIEF DESCRIPTION OF THE DRAWINGSThese and other features and advantages of this invention will become apparent in the following detailed description of the preferred embodiments of this invention, with reference to the accompanying drawings, in which:
Before the present invention is described in greater detail in connection with the preferred embodiments, it should be noted that similar elements and structures are designated by like reference numerals throughout the entire disclosure.
Referring to
The joint seat 1 includes a joint body 11 and a rotatable member 12 that is adapted to be connected fixedly to a residual thigh 8 of a prosthesis wearer and that has a pivot end 121 connected pivotally to the joint body 11, and a free end 122. The rotatable member 12 is configured generally as a horizontal plate. The support frame 2 has a lower end that is adapted to be connected fixedly to a prosthetic lower leg 9. A connecting unit includes a horizontal pivot pin 5 extending into an upper end of the support frame 2 and the joint body 11 so as to connect the upper end of the support frame 2 rotatably to the joint body 11 to thereby permit rotation of the lower leg 9 relative to the thigh 8. The hydraulic device 3 is disposed within the support frame 2, and has a piston rod 31 that is disposed movably in the support frame 2 and that is connected pivotally to a link 6, which is connected pivotally to the joint body 11. The pushing units 40 are located at two sides of the piston rod 31, as shown in
The push rod 41 is disposed movably within a vertical hole 112 in a top surface of the joint body 11, and is movable between an extended position shown in
When the artificial knee joint is flexed to deflect the lower leg 9 from the thigh 8, the free end 122 of the rotatable member 12 turns downward relative to the joint body 11 such that the push rod 41 is pressed by the free end 122 of the rotatable member 12 to move from the extended position shown in
With this invention thus explained, it is apparent that numerous modifications and variations can be made without departing from the scope and spirit of this invention. It is therefore intended that this invention be limited only as indicated by the appended claims.
Claims
1. An artificial knee joint for connecting a residual thigh of a prosthetic wearer to a prosthetic lower leg, said knee joint comprising:
- a joint seat including a joint body and a rotatable member that is adapted to be connected fixedly to the thigh and that has a pivot end connected pivotally to said joint body, and a free end;
- a hollow support frame having an upper end and a lower end that is adapted to be connected fixedly to the lower leg;
- a connecting unit for connecting said upper end of said support frame rotatably to said joint body so as to permit rotation of the lower leg relative to the thigh;
- a hydraulic device disposed within said support frame and having a piston rod that is disposed movably in said support frame and that is connected to said joint body;
- a push rod disposed movably within said joint body and movable between an extended position, where an upper end of said push rod projects from said joint body and where said free end of said rotatable member is spaced apart from said joint body to align the lower leg with the thigh, and a retracted position, where said upper end of said push rod is retracted into said joint body and where said free end of said rotatable member abuts against said joint body; and
- a biasing member for biasing said push rod to said extended position so that said free end of said rotatable member turns away from said joint body, thereby facilitating movement of the lower leg to a full extension position, where the lower leg is aligned with the thigh.
2. The artificial knee joint as claimed in claim 1, wherein said rotatable member is configured generally as a horizontal plate, said joint body having a top surface that is formed with a vertical hole, said push rod being disposed within said vertical hole in said joint body, said biasing member being configured as a coiled compression spring and being disposed within said vertical hole in said joint body so as to press said push rod upward against said free end of said rotatable member.
3. The artificial knee joint as claimed in claim 2, wherein said joint body further has an adjustment bolt that is disposed in said vertical hole and immediately under said coiled compression spring and that is adjustable to change biasing force of said coiled compression spring.
4. The artificial knee joint as claimed in claim 1, wherein said connecting unit includes a horizontal pivot pin extending into said upper end of said support frame and said joint body.
5. The artificial knee joint as claimed in claim 1, wherein said connecting unit includes four upright links, each of which has an upper end that is connected pivotally to said joint body, and a lower end that is connected pivotally to said upper end of said support frame.
Type: Application
Filed: Aug 18, 2003
Publication Date: Feb 24, 2005
Inventors: Chien-Liang Chen (Taipei City), Chien-Chuan Chen (Taipei City), I-Chun Chen (Taipei City)
Application Number: 10/642,220