초록 ▼

An integral stainless steel golf club head having a lead insert positioned directly behind the center of the intended striking surface of the club head is provided by using a “lost wax”procedure to mold an internally screwthreaded recess in the rear surface of the club head, into which a correspondi

An integral stainless steel golf club head having a lead insert positioned directly behind the center of the intended striking surface of the club head is provided by using a “lost wax”procedure to mold an internally screwthreaded recess in the rear surface of the club head, into which a correspondingly threaded lead insert of selected weight and length is inserted.

대표청구항 ▼

In a method of making a golf club head having a lead insert positioned therein directly behind the center of the intended striking surface of said head, comprising: providing a split mold assembly which, when assembled for casting, defines a first mold cavity of the same configuration as said golf c

In a method of making a golf club head having a lead insert positioned therein directly behind the center of the intended striking surface of said head, comprising: providing a split mold assembly which, when assembled for casting, defines a first mold cavity of the same configuration as said golf club head; filling said cavity with a molten wax-like material, and thereafter cooling said mold assembly to solidify said wax-like material in the form of a wax-like image of said golf club head; separating said split mold assembly to release said wax-like image from said split mold assembly, and then forming on said removed wax-like image a frangible coating of material; thereafter, melting said wax-like material within said coating and withdrawing it from within said coating to leave a second mold cavity in said coating of the same configuration as said golf club head; filling said second mold cavity with molten metal; cooling said molten metal in said second mold cavity to permit it to solidify and form said golf club head; and thereafter removing said frangible coating from said formed golf club head. the improvement comprising: during said forming of said wax-like image, providing an externally-threaded protrusion on said split mold assembly in a postion such that the threaded portion of said protrusion extends into said first mold cavity forwardly from the rear side thereof, thereby to form an internally-threaded recess extending into the rear surface of said wax-like image when it has solidified; after said solidifying of said wax-like image and before covering it with said coating material, unscrewing said threaded protrusion from said wax-like image to leave exposed said internal threads in said recess in said wax-like image, whereby said internal threads are replicated in said golf club head; and after said cooling of said molten metal to form said club head and after said frangible coating is removed, screwing an insert comprising lead into said internal threads thereof.