Polyurethane covered golf ball
AssigneeAcushnet Company
InventorsJohn Calabria, Dean A. Snell, Shenshen Wu
Life of this patent
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Abstract
The invention relates to a golf ball having a polyurethane cover substantially free of surface defects caused by a pin mold. By centering the golf ball core in its cover without the use of a mold having retractable or fixed alignment pins, a golf ball without surface defects in its cover resulting from the pins is achieved. To accomplish this "pinless" centering, a centering apparatus is used to properly position the golf ball core in the first mold half used to form the polyurethane cover.
Claims31
A golf ball comprising a core having a center portion and a polyurethane cover, wherein the ball is formed by:
- a) placing polyurethane into a first mold half and allowing said polyurethane to partially cure to a selected state of gel;
- b) centering the core in the first mold half by
- 1) placing the core into a golf ball core holder mounted on a moveable fixture, said fixture comprising an adjustable mold holding unit adapted for centering the core and receiving the first mold half, said adjustable mold holding unit comprising a frame unit capable of vertical movement and being aligned with the first mold half to permit the core to be centered in the first mold half;
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- 2) lowering the frame unit at a controlled rate toward the polyurethane in the first mold half, to contact the core with the polyurethane in the first mold half and to center the core in the first mold half;
- c) releasing the core from the core holder after a selected period of time;
- d) placing said core with the polyurethane while still in said first mold half against a second mold half having polyurethane at a selected state of gel therein and mating the first mold half with the second mold half;
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- e) curing the polyurethane in the mated mold halves, wherein the golf ball cover is substantially free of defects caused by a pin mold, and wherein the core center is substantially concentrically aligned with the golf ball cover.
A golf ball comprising a core having a center portion and a polyurethane cover, wherein the ball is formed by:
- a) providing a first mold member for molding material around part of a golf ball core wherein said first mold member comprises a first mold cavity;
- b) providing a mold member alignment unit having alignment members for cooperating with two side surfaces on the first mold member to align the mold member in a lateral position;
- c) providing a frame unit mounted for vertical movement relative to the mold member alignment unit for moving a golf ball core into the first mold cavity, comprising:
- i) a core holder for holding the core while it is moved into the first mold cavity;
- and
- ii) a stop for limiting the vertical movement of the frame unit;
- d) positioning the first mold member to a predetermined lateral position with the alignment members such that the core holder will center the golf ball core in the first mold member;
- e) placing a golf ball core in the core holder;
- f) placing a first portion of polyurethane in the first mold cavity;
- g) allowing said polyurethane to partially cure to a selected state of gel in said first mold cavity;
- h) moving the frame unit with the core holder and core continuously at a controlled rate towards the polyurethane in the first mold cavity until the core contacts the polyurethane, when the polyurethane is in said selected state of gel, and the core is centered in the first mold cavity;
- i) disengaging the core from the core holder after a selected period of time;
- j) placing such core with the polyurethane while still in said first mold cavity against a second mold member having a second mold cavity containing polyurethane at a selected state of gel therein and mating the two mold members together;
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- k) curing the polyurethane in the mated mold members, wherein the golf ball cover is substantially free of defects of a type caused by a pin mold, and wherein the core center is substantially concentrically aligned with the golf ball cover.
Dependencies are inferred from the claim text.