Pin support and mold for foaming and curing resin exterior over ball core

• US 4,436,276 A
• Filed: 09/20/1982
• Issued: 03/13/1984
• Est. Priority Date: 01/22/1982
• Status: Expired due to Fees

• Current Assignee: Cambridge Engineering Incorporated
• Original Assignee: Voplex Corporation
• Inventors: Donahue, Gordon J.
• Primary Examiner(s): Anderson, Philip E.
• Application Number:
  US06/419,904
• Time in Patent Office: 540 Days
• Field of Search: 249/91, 249/96, 249/97, 264/275, 264/278, 264/46.4, 264/46.9, 273/65 R, 425/817 R
• US Class Current: 249/91
• CPC Class Codes: B29C 33/123 for centering the inserts
• CPC Class Codes: B29C 44/1266 the preformed part being completely encapsulated, e.g. for packaging purposes or as reinforcement
• CPC Class Codes: B29L 2031/54 Balls

Abstract

Molding apparatus 10 or 11 supports a tough, resin ball core 15 in the center of a spherical mold cavity having upper and lower mold parts 12 and 13. Core 15 is about half the diameter of the mold cavity allowing room for foamed resin exterior 16 to form over and around core 15 filling the mold cavity and completing the spherical ball. A pin support 20 formed as a single pin 21 or a pair of identical pins 31 holds core 15 in the center of the mold cavity and is withdrawn after the ball is molded. The pin support is arranged at the mold parting plane and extends through the parts to the mold exterior thus providing full support and accurate location of the core within the mold cavity. A coupling element on pin support 20 is formed as a hook 28 or other engageable element outside the mold and is used for placing the core in the mold and also for supporting the ball for curing after molding.

Claims

1. A pin support and mold for foaming and curing a spherical resin exterior over a spherical ball core that is about one-half the diameter of said resin exterior, said pin support and mold comprising:

a. a two-part mold having a spherical cavity and a mold parting plane intersecting the center of said spherical cavity;

b. a bore hole extending through said mold parts at said mold parting plane, the axis of said bore hole being oriented to pass through said center of said spherical cavity;

c. a pin support including a straight shaft extending through a diameter of said core;

d. said shaft fitting snugly within said bore hole and extending for the length of said bore hole from one exterior side of said mold to an opposite exterior side of said mold to support said core within said spherical cavity;

e. said shaft having a locator abutment arranged to engage one of said exterior sides of said mold to locate said shaft axially relative to said mold exterior and thus locate said core within said spherical cavity;

f. said pin support extending outward beyond said locator abutment away from said engaged exterior side of said mold;

g. said outward extension of said pin support being formed as a coupling element disposed outside said mold;

h. said pin support being arranged so that, without moving said pin support, said mold parts can be separated when said foamed spherical resin exterior is partly cured, and said pin support can be moved clear of said mold to move said ball clear of said spherical cavity; and

i. said coupling element being shaped for hanging up said shaft to support said ball for curing in air out of contact with other surfaces for a curing time following molding of said resin exterior over said core.

2. The pin support and mold of claim 1 wherein said coupling element is formed as a hook.

3. The pin support and mold of claim 1 including a locator mark on said shaft for determining the position of said core on said shaft.