Metal shell golf club head, with keel

Claim 1

A golf club head, comprising (a) a metallic shell having the exterior form of said head, (b) the head having a front face adapted to strike a golf ball, and upper and lower surfaces, said lower surface defining a downwardly projecting keel which extends rearwardly relative to said front face, the keel having a downwardly convex surface which is forwardly and rearwardly elongated, said lower surface of the head having underside faces at opposite sides of the keel with each such face having downwardly concavity, (c) said keel defining a portion of said shell, (d) the shell defining a hollow interior, a portion of which lies adjacent an upwardly concave inner surface of the keel, (e) foamed synthetic plastic material filling said hollow interior including said portion adjacent said inner concave surface of the keel, and (f) a metallic weight structure attached to the shell at the inner side thereof and projecting to substantial extent into said hollow interior to be sidewardly surrounded and engaged by said foamed synthetic plastic material, said weight structure being everywhere offset from said inner concave surface of the keel, the keel also having upwardly convex inner surface extent, and the weight structure also extending closer to said keel upwardly convex inner surface extent than to said keel upwardly concave inner surface extent, (g) the shell having an integral metallic plate portion peripherally weld connected to the remainder of the shell, said integral plate portion forming said keel and also defining said concave underside faces whereby said plate portion has butterfly V-shape, said plate portion having forward edges extending forwardly sufficiently to be welded to downwardly V-shaped extent of said front face, and having rearward edges located at the rearward periphery of said keel and welded to rearward extent of the head, (h) the shell having a toe and a heel at opposite sides of a vertical plane passing forwardly through the keel, said weight structure located between said plane and said toe and carried by the plate portion intermediate said forward and rearward edges thereof.