Flexible grip with intermediate member

Abstract

A flexible tubular implement grip with a first section formed of elastomeric material having a first set of properties and a second section having a second different set of properties. An annular interface member is disposed between and abutted and bonded to the first and second section on opposite sides of the interface member. The interface member is fitted on a core bar and inserted therewith in a mold. The materials of different properties are then disposed concurrently in the mold, either for compression molding or by injection and cured in a single molding operation. The interface member may have grooves on the inner or outer periphery to provide positive interlocking engagement of the elastomeric material with the interface member.

1 . A flexible grip for a golf club shaft comprising:
 (a) a first tubular section formed of elastomeric material having a first set of properties;   (b) a second tubular section formed of elastomeric material having a second set of properties different from the first set;   (c) an annular interface member formed of elastomeric material disposed intermediate the first and second tubular sections wherein the material of the first section is bonded to the annular interface member on one side thereof and the material of the second tubular section is bonded to the annular interface on a side opposite the one side; and,   (d) wherein the annular interface member includes certain surfaces thereon engaging corresponding surfaces on the first and second tubular sections in positive interlocking relationship.   
     
     
         2 . The flexible grip of  claim 1 , wherein the certain surfaces include one of (i) axially extending grooves, and (ii) circumferentially extending grooves, wherein the grooves are formed on one of (i) an inner periphery, and (ii) an outer periphery of the annular member. 
     
     
         3 . The flexible grip of  claim 1 , wherein the annular member extends one of (i) partially, and (ii) completely through a thickness in a radial direction of the first and second tubular section. 
     
     
         4 . The flexible grip of  claim 1 , further comprising an end cap disposed on the second tubular section with a second annular interface member disposed between the end cap and the second tubular section. 
     
     
         5 . The flexible grip of  claim 1 , wherein the annular interface member is formed of one of (i) cured thermoplastic, (ii) partially cured thermoplastic, and (iii) thermosetting elastomer. 
     
     
         6 . The flexible grip of  claim 1 , wherein the first and second set of properties have a different including one of (i) durometer hardness, (ii) color, (iii) composition, and (iv) density. 
     
     
         7 . A method of making a flexible tubular grip for the handle of an implement of the type to be moved with speed and force comprising:
 (a) disposing an annular interface member on a core bar;   (b) inserting the core bar with the annular interface member thereon in a mold;   (c) concurrently injecting elastomeric material having a first set of properties on one side of the interface member and elastomeric material having a second set of properties into the mold on the side of the annular interface member opposite the one side and forming the grip;   (d) curing the grip in the mold; and,   (e) removing the grip from the mold and removing the core bar from the grip.   
     
     
         8 . The method of  claim 7 , wherein concurrently injecting includes one of (i) simultaneously injecting into the mold, and (ii) serially injecting into the mold. 
     
     
         9 . The method of  claim 7 , wherein disposing an annular interface member includes forming certain positive interlocking surfaces on the annular interface member on one of (i) the inner, and (ii) the outer periphery thereof. 
     
     
         10 . The method of  claim 7 , wherein concurrently injecting includes injecting elastomeric material with one of the first and second set of properties having a Mooney viscosity less than 38.