US 2075583 A
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Description (OCR text may contain errors)
March 30, 1937. G. LANGE 2,075,583
FOOT FOR ARTIFICIAL LIMBS Filed Aug. 51, 1935 Gpb Lieb Lange,
@25% MMM/Imm* Patented Mar. 30, 1937 'f- UNITEDI STATES PATENT oFFlc-E 3 Claims.
My invention relates to improvements in feet for articial limbs, particularly those of the pneumatic type, and it consists in the combination, constructions and arrangements herein described and claimed.
An object of my invention is to provide a foot for an artificial limb which is durable, and which will flex in walking in a manner to simulate that of the natural foot.
A further object is to provide a pneumatic foot which may be easily inflated, but in which the means for ination is concealed. y
A further object is to provide a device of the type described in which there is a central metallic core which takes the main weight of the user, but works in cooperation with a rubber form so as to give stability and exibility.
A further object of the invention is to provide a device of the type described having a metal core which is so disposed that it may have a limitated rotative movement at a point approximating the ankle of the natural foot and also a similar movementJ in connection with the rubber form at a point where the toes of the natural foot flex in the action of walking.
A further object of the invention is to provide a device of the type described which is composed of relatively few parts, and which therefore is not easily liable to get out of order.
My invention is illustrated in the accompanying drawing forming part of this application, in which:
Figure 1 is a central sectional view through the foot and the shoe, and,
Figure 2 is a perspective view of the core.
In carrying out my invention I provide a rubber form like that shown in the drawing. This form, as will be noted, has a base portion 3, a toe portion ffl, an instep portion 5, ankle portions 6 and a heel portion l, all these portions being formed integrally. At the top of the ankle portions are integrally inwardly extending flanges 8. The interior of the form is hollow, as shown. At 9 I have indicated an integral rubber boss above the heel and at Il) a similar smaller boss.
The core is made of metal, preferably aluminum, and is of the shape shown in the drawing. It consists of a body portion I I having a substantially cylindrical extension I2, which is provided with a recess of a shape to conform to' the contour of the boss 9.
An angular extension I3 has an expanded end III provided with a recess to conform with and receive the boss IIJ. The top of this core is flattened, as shown at I5, and is p-rovided with threaded lugs I6, which extend through the flanges 3 and through the bottom I'I of a cupshaped member I9 being held by nuts 20. The core is recessed to receive a valve stem 2I and is provided with an air passage 22 communicating with the hollow form. The member I9 is preferably riveted to a shin plate 23, as shown in the drawing. The pneumatic foot is completed by the shoe 24, which in this instance is shown as oxford type.
From the foregoing description of the various types of the device the operation thereof may be readily understood. Access to the valve stem 2I may be had from an opening (not shown) in the shin guard, or in some other place which is covered. The foot is inflated after the manner of a pneumatic tire until it assumes the proper form. Now in the act of walking it will be 0bserved that if the heel strikes the ground rst, as it does when most people walk, the greater portion of the weight will come on the core body, the boss 9, and the heel of the shoe. There is a slight pivotal movement to bring the foot to the ground and the foot is flexed at the base of the toes as the movement proceeds.
This flexure is taken care of by these two bosses 9 and I0, since they permit a bending movement as the walking proceeds. The flexing of the pneumatic foot is aided by the hollow construction, while at the same time the fact that the foot is distended with the air tends to return the foot to natural form immediately after the flexing action is over.
1. A pneumatic foot for artificial limbs comprising a hollow resilient foot-shaped body, a solid core within said body, said core having a downwardly extending substantially cylindrical portion provided with a recess, and an integral angularly disposed portion provided with a recess at the end thereof, said resilient foot-shaped body having integral bosses exten-ding upwardly from the bottom of said foot-shaped body and arranged to enter the recesses in said core, and means for securing the top of the resilient footshaped body to the top of the core.
2. A pneumatic foot for articial limbs comprising a hollow resilient foot-shaped body, a metal core within said body, said metal core having an air passage and being provided with a substantially cylindrical portion having a recess and an angularly disposed portion provided with a flared end, and a recess in said end, said resilient body having a boss near the heel to enter the recess in the cylindrical portion of the core,
and a second boss near the ball of the foot-shaped body arranged to enter the recess in the angularly extending portion of the core, an air Valve disposed in the air passage of said core at one end of the passage, the opposite end of the passage communicating with the space between the core and the inner Wall of the foot-shaped body, and means for securing the top of the core to the resilient foot-shapedbody.
3. A pneumatic foot for artificial limbs comprising a hollow resilient foot-shaped body having inwardly extending anges, a metal core, a cup-shaped member disposed abo-ve said flanges, means for clamping the flanges between the core and said cup-shaped member, a shin plate secured to said cup-shaped member, said metal core having a central bore, land a laterally extending air passage communicating therewith, a valve stem disposed in the bore in said core, said core having a substantially cylindrical portion, the axis of the cylindrical portion extending through the heel, said core having an angular integral extension provided with a downwardly turned are-d end, the cylindrical portion of the core and said flared end having recesses, and in tegral bosses carried by the foot-shaped body for entering said recesses whereby a slight pivotal movement of the core at each of said bosses is permitted.