Pivot joint adapter

Abstract

An adapter for permitting insertion of a pivot joint at the ankle of an artificial leg has a body provided with a protuberant part arranged for attachment to a pivot joint connected to the lower portion of an artificial leg. An aperture provided in a planar base of the body receives an insert that has an opening arranged for engaging a fastener and connecting the adapter body to a foot portion of the artificial leg. In this manner a pivot joint intended for insertion in an artificial leg between, for example, the knee and ankle portions can be arranged in the ankle region of the artificial leg without necessitating modification of the foot portion of the leg.

Parent Case Text

CROSS REFERENCE TO RELATED APPLICATION

This application is a continuation-in-part of my application Ser. No. 284,974, filed Aug. 30, 1972 and entitled "Pivot Joint" which issued as U.S. Pat. No. 3,842,443, on Oct. 22, 1974.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to prosthetic devices, and particularly to a pivot joint adapter for use with an artificial leg, and the like.

2. Description of the Prior Art

My application, Ser. No. 284,974, filed Aug. 30, 1972, discloses a pivot joint specifically intended for insertion between the knee and ankle regions of conventional artificial limbs. This pivot joint is attached to adjacent sections of the artificial limb in a suitable manner, such as screw threads and/or retaining pins. While such devices are readily attachable to artificial limbs of standard construction, they are not matable to a foot portion of the conventional artificial limbs if it is desired to use such a pivot joint as an ankle joint.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an adapter permitting a pivot joint to be connected to the foot portion of an artificial leg.

It is another object of the present invention to provide an adapter specifically intended for connecting to a foot portion of an artificial leg a pivot joint as disclosed in my copending application Ser. No. 284,974, filed Aug. 30, 1972.

These and other objects are achieved according to the present invention by providing an adapter having a body provided with an arrangement permitting attachment of the body to a pivot joint, and a further arrangement permitting connection of the body to a foot portion of an artificial leg. The pivot joint itself is connected to a lower portion of the artificial leg.

According to a preferred embodiment of an adapter according to the present invention, the body includes a planar base and a protuberant part extending from the base. A recess provided in the protuberant part permits attachment of the body to a mating pivot joint. The recess is partially defined by a substantially circular wall, and internal screw threads are provided on the wall and arranged for receiving a threaded portion of a pivot joint.

The body further includes an aperture provided in the planar base and arranged substantially equidistant from all portions of the circular wall. An insert is disposed in the aperture and arranged for receiving a fastener which attaches the insert, and therefore the body of the adapter, to the foot portion of an artificial limb.

A preferred insert according to the present invention has a shank arranged for mating with the aperture, a flange attached to the shank and arranged for abutting the planar base in the manner of a shoulder, and an opening provided in the shank and arranged passing therethrough. The opening may be provided with internal screw threads arranged for threadingly engaging the screw threads of a bolt passing through the associated foot portion to which the adapter is attached.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a partly schematic, perspective view showing an adapter according to the present inventon connecting a pivot joint to the foot portion of an artificial leg.

FIG. 2 is a fragmentary, sectional view taken generally along the line 2--2 of FIG. 1.

FIG. 3 is a sectional view, with some parts removed, taken generally along the line 3--3 of FIG. 2.

FIG. 4 is an exploded, perspective view showing an adapter according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now more particularly to FIG. 1 of the drawings, an ankle joint 10 for an artificial leg has a pivot joint 12 connectable to a lower leg portion 14 of the artificial leg, and an adapter 16 according to the present invention attached to pivot joint 12 and connectable to a foot portion 18 of the artificial leg. In this manner, pivot joint 12 is connected to foot portion 18 by adapter 16 without necessitating modification of foot portion 18.

Referring now to FIGS. 2 and 3 of the drawings, pivot joint 12 is constructed from first and second joint segments 20 and 22 connected together for pivotal movement relative to one another about a pivot axis A--A as by a bolt 24 passing through bores 26 and 28 provided in segments 20 and 22, and a nut 30 threaded onto bolt 24. A sleeve 32 constructed from a suitable, known bearing material may be inserted into bores 26 and 28, with only bore 28 being shown as so provided. Suitable, conventional thrust bearings 34 and 35 may be arranged between segments 20 and 22 and in the recess of segment 22 communicating with adapter 16 to facilitate the pivotal movement of joint 12. A recess 36 is advantageously provided in at least one of segments 20, 22, segment 22 being so provided in FIG. 2, for receiving bearing 34, with bearing 34 being arranged in recess 36. A resilient sleeve 38 is arranged around segments 20, 22 for restoring same to a predetermined relationship with respect to one another following the application of a torsional force to the segments. Conventional clamps 40 and 42 including respective bands 44 and 46 are arranged about sleeve 38 for clamping same to segments 20 and 22, respectively. The torque exerted by sleeve 38 may be decreased by moving clamps 40, 42 further apart, and increased by arranging them closer together. This adjustment can be useful for providing a different degree of torque for persons of, for example, different weights.

Although a pivot joint 12 has been found especially suitable for use with an adapter 16 according to the present invention, it is to be understood that other suitable pivot joints may be similarly employed. Accordingly, the pivot joints disclosed in my copending application Ser. No. 284,974, filed Aug. 30, 1972, are incorporated herein, and it is to be understood that these other pivot joints may be suitably used with an adapter according to the present invention. For example, apertures could be provided in the adapter for receiving a retaining pin passing transversely through the associated pivot joint segment.

Pivot joint 12 is specifically provided with threaded portions 48 and 50 for attachment to portions 14 and 18, respectively. Threaded portion 48 is threaded into the internal screw threads of a hollowed-out section 52 of segment 20, while portion 50 is connected to adapter 16 in a manner to be described below.

Adapter 16 has a body 54 including a planar, elongated base 56 and a protuberant part 58 in the form of a boss extending from base 56. Although an elongated base 56 is illustrated in FIGS. 1 and 4 of the drawings, it is to be understood that the base may take other configurations as desired. A recess 60 is provided in protuberant part 58, and is partially defined by a substantially circular wall 62 having internal screw threads arranged for receiving a threaded portion 50 of pivot joint 12. An aperture 64 is provided in base 56, which cooperates with wall 62 to define recess 60, and is arranged substantially equidistant from all portions of wall 62. An insert 66 is disposed in aperture 64 for a purpose which will be made clear below.

Insert 66 includes a shank 68 arranged for mating with aperture 64. A flange 70 is attached to shank 68, and is arranged for abutting the recess forming surface of base 56 in the manner of a shoulder for limiting movement of insert 66 in aperture 64. An opening 72, furnished with internal screw threads, is provided in shank 68 and arranged passing therethrough so as to pass from recess 60 through base 58. A conventional fastener such as bolt 72 may be arranged with the screw threads thereof threadingly engaging the threads of opening 72 for connecting insert 66, and therefore adapter body 54, to foot portion 18 by passing the shank of bolt 74 through a hole 66 conventionally provided extending through portion 18 from a counterbore 78 thereof. A nut 80 may be threaded onto the end threads of bolt 74 if desired to provide additional strength and rigidity of the connection.

A plurality of threaded bores 82 may be provided in the cylindrical boss formed by protuberant part 58. These bores 82 are arranged radially to wall 62 and parallel to base 56 for receiving setscrews 84, and the like, and clamping a portion of a pivot joint segment received in a socket-forming recess equivalent to recess 60. In this manner, the segment portion received in the recess may be clamped in place, either solely by the setscrews 84 or in addition to the illustrated screw threads on the segment portion and wall 62.

Although it is to be understood that any suitable, known materials may be used to construct the various elements described above, a high grade aluminum has been found satisfactory for adapter body 54, while a steel may be used for insert 66. In this manner article weight and fabrication costs can be minimized while achieving the requisite strength and rigidity of the resulting structure. A block 86 constructed from, for example, a suitable synthetic such as a phenolic, is advantageously attached to the lower end of portion 14 for facilitating attachment of threaded portion 48 to the leg portion.

Alternatively to the attachment of an adapter according to the present invention to an associated segment of a pivot joint, other suitable attachment techniques such as a tapered screw thread provided joint segment and cooperating jamnut or a transversely extending pin passing through the joint segment, as set out in my aforementioned copending application incorporated herein by reference, may be employed. In the former alternative, either the adapter itself would form a jamnut, or a jamnut would be fitted within the socket-forming recess of the adapter body, while in the latter alternative, diagonally opposed holes parallel to the planar base would be formed in protuberant part 58.

As can be appreciated from the above description and from the drawings, an adapter according to the present invention permits a pivot joint intended for insertion into an artificial leg to be connected to the foot portion of the artificial leg quickly and easily without modification of the foot portion.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention.

Claims

What is claimed as new is as follows:

1. An adapter for permitting attachment of a pivot joint to the foot portion of an artificial leg, comprising a body provided with means for attaching the body to a pivot joint, and with means for connecting the body to a foot portion of an artificial leg, the body including a planar base and a protuberant part extending from the base, and the means for attaching including a recess provided in the protuberant part and partially defined by a substantially circular wall, and internal screw threads provided on the wall and arranged for receiving a threaded portion of a pivot joint, and the body further including an aperture provided in the base and arranged substantially equidistant from all portions of the circular wall, and the means for connecting including an insert disposed in the aperture, the insert including a shank arranged for mating with the aperture, a flange attached to the shank and arranged for abutting the base in the manner of a shoulder, the shank arranged for abutting the foot portion, and an opening provided in the shank and arranged passing therethrough, retaining means including internal screw threads for threadingly engaging with the screw threads of a bolt arranged passing through the foot portion and securing the foot portion to the adaptor.

2. A structure as defined in claim 1, wherein the protuberant part is a cylindrical boss, and the means for attaching further includes bores having internal screw threads provided in the boss and arranged radially to the circular wall and parallel to the base for receiving setscrews that clamp a portion of a pivot joint received in the recess.

3. A structure as defined in claim 2, wherein the base is elongated.

4. An ankle joint for an artificial leg, comprising, in combination:

a. a pivot joint connectable to a lower leg portion of an artificial leg; and

b. an adapter attached to the pivot joint and connectable to a foot portion of the artificial leg, whereby the pivot joint is connected to the foot portion; wherein

c. the pivot joint includes:

i. first and second joint segments;

ii. means connecting the first and second joint segments together for pivotal movement relative to one another about a pivot axis;

iii. a bearing member;

iv. a recess provided in one of the first and second joint members and arranged for receiving the bearing member, the bearing member being arranged in the recess;

v. resilient means including a sleeve arranged around the first and second joint segments for restoring same to a predetermined relationship with respect to one another following the application of a torsional force to the segments; and

vi. means for attaching the first and second joint segments to the lower leg portion and foot portion, respectively; and

d. the adapter includes a body provided with means for attaching the body to a pivot joint, and with means for connecting the body to a foot portion of an artificial leg, the body including a planar base and a protuberant part extending from the base, and the means for attaching including a recess provided in the protuberant part and partially defined by a substantially circular wall, and internal screw threads provided on the wall and arranged for receiving a threaded portion of a pivot joint, the body further including an aperture provided in the base and arranged substantially equidistant from all portions of the circular wall, and the means for connecting including an insert disposed in the aperture, the insert including a shank arranged for mating with the aperture, a flange attached to the shank and arranged for abutting the base in the manner of a shoulder, and an opening provided in the shank and arranged passing therethrough, the opening provided with internal screw threads, a bolt arranged passing through the foot portion, and the internal screw threads of the opening arranged for threadingly engaging with the screw threads of the bolt.

5. A structure as defined in claim 4, wherein the protuberant part is a cylindrical boss, and the means for attaching further includes bores having internal screw threads provided in the boss and arranged radially to the circular wall and parallel to the base for receiving setscrews that clamp a portion of a pivot joint received in the recess.

6. A structure as defined in claim 4, wherein the base is elongated.

7. A pivot joint for an artificial leg, comprising, in combination:

a. first and second joint segments;

b. means connecting the first and second joint segments together for pivotal movement relative to one another about a pivot axis;

c. a bearing member;

d. a recess provided in one of the first and second joint members and arranged for receiving the bearing member, the bearing member being arranged in the recess;

e. resilient means including a sleeve arranged around the first and second joint segments for restoring same to a predetermined relationship with respect to one another following the application of a torsional force to the segments; and

f. means for attaching the first and second joint segments to portions of a member to be pivotally connected together, the means for pivotal movement including a bolt arranged passing through coaxial bores provided in the first and second joint segments and engaging a nut threaded onto the bolt, a sleeve constructed from a bearing material and inserted into the bore of one of the joint segments, and a further bearing being arranged between the nut and surface of the joint segment arranged adjacent the nut.