System for molding a jointed linkage support system

• US 20030205842A1
• Filed: 06/11/2003
• Published: 11/06/2003
• Est. Priority Date: 09/19/2000
• Status: Active Grant

• Current Assignee: CJ Associates Ltd.
• Original Assignee: CJ Associates Ltd.
• Inventors: Kwan, Chiu-Keung, Lee, James S. W.
• Granted Patent: US 6,932,669 B2
• Time in Patent Office: Days
• US Class Current: 264/242
• CPC Class Codes: A63H 3/46 Connections for limbs
• CPC Class Codes: B29C 2045/002 using shrinkage
• CPC Class Codes: B29C 45/0017 moulding interconnected elements which are movable with respect to one another, e.g. chains or hinges
• CPC Class Codes: B29C 45/14467 Joining articles or parts of a single article B29C45/14377, B29C45/14385, B29C45/14581, B29C45/14614 and B29C45/006 take precedence
• CPC Class Codes: B29C 65/665 using shrinking during cooling
• CPC Class Codes: B29L 2031/5218 Dolls, puppets
• CPC Class Codes: Y10T 403/32631 Universal ball and socket

Abstract

A system for molding a jointed linkage support system with joints that allow movement and bending in many directions and degrees of freedom. A chain-like linkage system made up of a series of joints is molded in a single step from materials having different melting temperatures in a series of alternating communicating mold cavities. The jointed linkage support system emerges from the mold fully assembled. An electrical switch may be provided within one of the joints between sleeves and rods whereby movement of the rod relative to the sleeve actuates the switch.

Claims

1. A system for molding a jointed linkage, the system comprising:

a mold having a first set of cavities with contours corresponding to a first part and a second set of cavities with contours corresponding to a second part, wherein the first and second sets of cavities are in communication and are positioned such that a plurality of individual cavities of the first set of cavities alternate with a plurality of individual cavities of the second set of cavities, and wherein at least one of the first set of cavities is bisected by a plane of symmetry between two identical socket part mold cavities;

a plurality of first parts each having a first melting point, wherein the first parts are placed into the first set of cavities with portions of the first parts extending into the second set of cavities;

means for introducing a material having a second melting point which is lower than the first melting point into the second set of cavities at a temperature which is equal to or higher than the second melting point and lower than the first melting point to form a plurality of second parts that alternate with the plurality of first parts in the jointed linkage; and

wherein the second parts capture the portions of the first parts which extend into the second set of cavities to form movable joints between the first and second alternating parts.

2. The system of claim 1 wherein each of the plurality of first parts comprises at least two balls and each of the plurality of second parts has sockets to capture the balls of the first parts to form the movable joints.

3. A jointed linkage support system made by a method comprising the steps of:

providing a mold with a series of individual communicating cavities, a first set of the individual cavities configured to receive a first part, each of the first parts having a first contour, and a second set of the individual cavities configured to form a second part, each of the second parts having a second contour, with the individual cavities of the first set positioned such that a plurality of individual cavities of the first set alternate with a plurality of individual cavities of the second set;

making a plurality of the first parts from a first material having a first melting point;

placing the first parts in the first set of cavities with portions of the first parts extending into the second set of cavities;

introducing into the second set of cavities a second material having a second melting point which is lower than the first melting point to form the second part, wherein the second material is introduced into the second set of cavities at a temperature that is equal to or higher than the second melting point and lower than the first melting point;

allowing the second material to cool in the second cavities to form a movable joint with the portions of the first parts which extend into the second set of cavities, thereby molding a jointed linkage support system in which the first parts pivot with respect to the second parts without any of the second parts engaging an adjacent one of the second parts.

4. The jointed linkage support system made by the method of claim 3 wherein the second material has a shrink characteristic for gripping the first part.

5. The jointed linkage support system made by the method of claim 3 wherein the movable joint is a ball and socket joint.

6. The jointed linkage support system made by the method of claim 3 further comprising the steps of providing the mold with a third set of cavities;

making a switch assembly from a material having a melting point greater than the second melting point;

placing the switch assembly in a cavity of the third set of cavities with a portion of the switch assembly extending into a cavity of the second set of cavities before the second material is introduced into the second set of cavities; and

introducing the second material into the second set of cavities to form movable joints with the first parts and the switch assembly.

7. The jointed linkage support system made by the method of claim 6 wherein the switch assembly comprises a first contact element associated with a first switch assembly part;

and

a second contact element associated with a second switch assembly part, wherein angular movement of the first switch assembly part relative to the second switch assembly part causes the second contact element to engage the first contact element.

8. The jointed linkage support system made by the method of claim 7 wherein the second switch assembly part further comprises a sleeve with a socket formed at one end and the second contact element comprises a conductive annular ring within the sleeve and adjacent the socket.

9. The jointed linkage support system made by the method of claim 8 further comprising a conductive shaft extending axially through the first switch assembly part, the shaft having a first and second ends;

and

a spring mounted to and extending from the first end of the shaft, the first contact element being mounted on a distal end of the spring.

10. The jointed linkage support system made by the method of claim 9 further comprising a first electrical lead extending from the second end of the conductive shaft, the first electrical lead being in electrical contact with the first contact element through the shaft and spring;

and

a second electrical lead extending from the sleeve, the second electrical lead connected to the second contact element.