Golf club head

Abstract

A golf club head having a planar strike face formed of oxidizable metal substrate including an unplated portion of the oxidizable metal substrate that is not plated and defines an oxidizable strike face surface area. A first oxidation-prevention coating permanently covers at least a portion of the body including at least a portion of the rear portion and the heel portion, and a temporary user-removable cover is located over at least a portion of the oxidizable strike face surface area and may temporarily regulate oxidation. The club head has performance and confidence inspiring ratios of the oxidizable strike face surface area divided by the total volume, as well as the oxidizable strike face surface area divided by the total planar strike face surface area, and the oxidizable strike face surface area divided by the total surface area.

We claim: 
     
         1 . A wedge-type golf club head, comprising:
 a body having a sole portion, a top portion, a heel portion, a toe portion, a rear portion, a front portion, a loft of 45 degrees or more, and a center of gravity located vertically 16-23 mm above a horizontal ground plane with the golf club head resting on the horizontal ground plane in a proper address position, wherein:   the front portion includes a planar strike face having a plurality of primary grooves, with each of the plurality of primary grooves having a most-toeward end and a most-heelward end;   the planar strike face is formed of oxidizable metal substrate including an unplated portion of the oxidizable metal substrate that is not plated, and the unplated portion includes (a) each of the primary grooves, (b) all portions of each primary groove, and (c) all of the area between adjacent primary grooves, thereby defining an oxidizable strike face surface area;   the planar strike face has a total planar strike face surface area;   an imaginary par line on the front portion along a transition from the planar strike face to a curved transition region;   the body has a total volume, measured using a water-displacement method, that excludes the portion of the heel portion that is heelward of the imaginary par line;   the body has a total surface area that excludes the portion of the heel portion that is heelward of the imaginary par line;   a first oxidation-prevention coating permanently covers at least a portion of the body including at least a portion of the rear portion and the heel portion;   a temporary user-removable cover over at least a portion of the oxidizable strike face surface area and the most-toeward end and most-heelward end of at least two of the plurality of primary grooves that temporarily regulates oxidation;   a ratio of the oxidizable strike face surface area divided by the total volume is 0.08-0.12 per mm;   a ratio of the oxidizable strike face surface area divided by the total planar strike face surface area is at least 0.70; and   a ratio of the oxidizable strike face surface area divided by the total surface area is 0.25-0.40.   
     
     
         2 . The wedge-type golf club head of  claim 1 , wherein the temporary user-removable cover has an external periphery and is formed to display within the external periphery a displayed portion of the planar strike face and a displayed portion of the at least two of the plurality of primary grooves whose most-toeward end and most-heelward end are covered. 
     
     
         3 . The wedge-type golf club head of  claim 1 , wherein the first oxidation-prevention coating permanently covers the hosel and the curved transition region, and the unplated portion of the oxidizable metal substrate of the planar strike face extends to a bottom edge of the planar strike face. 
     
     
         4 . The wedge-type golf club head of  claim 3 , wherein the first oxidation-prevention coating permanently covers a portion of the front portion located between the curved transition region and the most-heelward end of each of the plurality of primary grooves, and the unplated portion of the oxidizable metal substrate of the planar strike face extends to a top edge of the planar strike face. 
     
     
         5 . The wedge-type golf club head of  claim 4 , wherein the unplated portion of the oxidizable metal substrate of the planar strike face extends to a toe edge of the planar strike face, and the total surface area is no more than 9,292 mm{circumflex over ( )}2. 
     
     
         6 . The wedge-type golf club head of  claim 5 , further including a plurality of auxiliary grooves located between the primary grooves, and wherein the temporary user-removable cover extends over at least a portion of the plurality of auxiliary grooves and does not extend into the plurality of primary grooves. 
     
     
         7 . The wedge-type golf club head of  claim 6 , wherein the plurality of auxiliary grooves includes auxiliary grooves located a first vertical distance above the horizontal ground plane that is greater than a second vertical distance above the horizontal ground plane to a highest primary groove. 
     
     
         8 . The wedge-type golf club head of  claim 7 , wherein the plurality of auxiliary grooves includes auxiliary grooves located between a most-toeward point on the planar strike face and the most-toeward end of each primary groove. 
     
     
         9 . The wedge-type golf club head of  claim 8 , wherein a portion of the planar strike face has a thickness of at least 4.8 mm, and the ratio of the oxidizable strike face surface area divided by the total planar strike face surface area is at least 0.75. 
     
     
         10 . The wedge-type golf club head of  claim 9 , wherein the ratio of the oxidizable strike face surface area divided by the total planar strike face surface area is 1.00. 
     
     
         11 . The wedge-type golf club head of  claim 2 , further including a plurality of auxiliary grooves located between the primary grooves, wherein the temporary user-removable cover is formed to display within the external periphery a displayed portion of the auxiliary grooves and cover a portion of the auxiliary grooves. 
     
     
         12 . The wedge-type golf club head of  claim 11 , wherein the plurality of auxiliary grooves includes auxiliary grooves located a first vertical distance above the horizontal ground plane that is greater than a second vertical distance above the horizontal ground plane to a highest primary groove. 
     
     
         13 . The wedge-type golf club head of  claim 12 , wherein the plurality of auxiliary grooves includes auxiliary grooves located between a most-toeward point on the planar strike face and the most-toeward end of each primary groove. 
     
     
         14 . The wedge-type golf club head of  claim 2 , wherein the temporary user-removable cover has a percent elongation between 110% and 170%. 
     
     
         15 . The wedge-type golf club head of  claim 2 , wherein the temporary user-removable cover includes a non-stick tab coupled to an external periphery of the temporary user-removable cover. 
     
     
         16 . The wedge-type golf club head of  claim 1 , wherein the temporary user-removable cover includes an adhesive to adhesively attach to the planar strike face and seal an underlying area of the planar strike face from environmental exposure and inhibit oxidation. 
     
     
         17 . The wedge-type golf club head of  claim 2 , wherein temporary user-removable cover is formed with an opening to reveal and expose a portion of the planar strike face and a portion of the plurality of primary grooves, thereby defining a region of oxidation-defined indicia created by a contrast of differing stages of oxidation on the planar strike face. 
     
     
         18 . The wedge-type golf club head of  claim 1 , wherein the temporary user-removable cover is configured to display a first portion of the planar strike face including the at least two of the plurality of primary grooves whose most-toeward end and most-heelward end are covered, wherein the first portion is within an external periphery of the temporary user-removable cover and the first portion is surrounded by the temporary user-removable cover. 
     
     
         19 . A wedge-type golf club head, comprising:
 a body having a sole portion, a top portion, a heel portion, a toe portion, a rear portion, a front portion, a loft of 45 degrees or more, and a center of gravity located vertically 16-23 mm above a horizontal ground plane with the golf club head resting on the horizontal ground plane in a proper address position, wherein:   the front portion includes a planar strike face having a plurality of primary grooves, with each of the plurality of primary grooves having a most-toeward end and a most-heelward end, and a plurality of auxiliary grooves located between the primary grooves, wherein the plurality of auxiliary grooves includes auxiliary grooves located a first vertical distance above the horizontal ground plane that is greater than a second vertical distance above the horizontal ground plane to a highest primary groove, and the plurality of auxiliary grooves includes auxiliary grooves located between a most-toeward point on the planar strike face and the most-toeward end of each primary groove;   the planar strike face is formed of oxidizable metal substrate including an unplated portion of the oxidizable metal substrate that is not plated, and the unplated portion includes (a) each of the primary grooves, (b) all portions of each primary groove, and (c) all of the area between adjacent primary grooves including a portion of the plurality of auxiliary grooves, thereby defining an oxidizable strike face surface area, and the unplated portion of the oxidizable metal substrate of the planar strike face extends from a bottom edge of the planar strike face to a top edge of the planar strike face and to a toe edge of the planar strike face;   the planar strike face has a total planar strike face surface area;   an imaginary par line on the front portion along a transition from the planar strike face to a curved transition region;   the body has a total volume, measured using a water-displacement method, that excludes the portion of the heel portion that is heelward of the imaginary par line;   the body has a total surface area that excludes the portion of the heel portion that is heelward of the imaginary par line, wherein the total surface area is no more than 9,292 mm{circumflex over ( )}2;   a first oxidation-prevention coating permanently covers at least a portion of the body including at least a portion of the rear portion, the hosel, the curved transition region, and a portion of the front portion located between the curved transition region and the most-heelward end of each of the plurality of primary grooves;   a temporary user-removable cover over at least a portion of the oxidizable strike face surface area and the most-toeward end and most-heelward end of at least two of the plurality of primary grooves that temporarily regulates oxidation, wherein the temporary user-removable cover extends over at least a portion of the plurality of auxiliary grooves and does not extend into the plurality of primary grooves;   a ratio of the oxidizable strike face surface area divided by the total volume is 0.08-0.12 per mm;   a ratio of the oxidizable strike face surface area divided by the total planar strike face surface area is at least 0.70;   a ratio of the oxidizable strike face surface area divided by the total surface area is 0.25-0.40; and   wherein the first oxidation-prevention coating permanently covers the hosel and the curved transition region.   
     
     
         20 . The wedge-type golf club head of  claim 19 , wherein the temporary user-removable cover is formed to display within an external periphery a displayed portion of the auxiliary grooves and cover a portion of the auxiliary grooves.