Iron-type golf club head

Abstract

Disclosed herein is an iron-type golf club head comprising a body comprising a heel portion, a sole portion, a toe portion, and a topline portion. The topline portion has a mass per unit length of between 0.09 g/mm and 0.40 g/mm. The golf club head also comprises a strike plate coupled to the body at a front portion of the golf club head and a cavity defined between the topline portion, the sole portion, and the strike plate. The golf club head further comprises a bridge bar at a rear portion of the golf club head. The bridge bar spans the cavity, is spaced apart from the strike plate, and is rigidly fixed to and extends uprightly between the sole portion and the topline portion. The bridge bar has a mass per unit length of between 0.09 g/mm and 0.40 g/mm.

1 . An iron-type golf club head, comprising:
 a body comprising a heel portion, a sole portion, a toe portion, and a topline portion, wherein the topline portion has a mass per unit length of between 0.09 g/mm and 0.40 g/mm;   a strike plate coupled to the body at a front portion of the golf club head;   a cavity defined between the topline portion, the sole portion, and the strike plate; and   a bridge bar at a rear portion of the golf club head, the bridge bar spanning the cavity, spaced apart from the strike plate, and rigidly fixed to and extending uprightly between the sole portion and the topline portion, wherein the bridge bar has a mass per unit length of between 0.09 g/mm and 0.40 g/mm.   
     
     
         2 . The iron-type golf club head according to  claim 1 , wherein:
 a Z-up of the golf club head is below about 20 mm;   the topline portion comprises weight reducing features that shift a Z-up of the golf club head downward by at least 0.4 mm; and   the bridge bar shifts the Z-up of the golf club head upward by less than 2.0 mm.   
     
     
         3 . The iron-type golf club head according to  claim 2 , wherein the weight reducing features shift the Z-up of the golf club head downward by at least 1.0 mm. 
     
     
         4 . The iron-type golf club head according to  claim 1 , wherein the topline portion comprises weight reducing and stiffening features comprising:
 a rearwardly and downwardly directed overhang; and   a plurality of ribs coupled to an underside of the overhang.   
     
     
         5 . The iron-type golf club head according to  claim 4 , wherein the bridge bar is fixed to one rib of the plurality of ribs. 
     
     
         6 . The iron-type golf club head according to  claim 1 , wherein the bridge bar is hollow. 
     
     
         7 . The iron-type golf club head according to  claim 1 , wherein the bridge bar comprises at least one web and at least one flange angled relative to the at least one web. 
     
     
         8 . The iron-type golf club head according to  claim 1 , wherein a cross-section of the bridge bar is T-shaped. 
     
     
         9 . The iron-type golf club head according to  claim 1 , wherein the bridge bar has a mass per unit length of between 0.09 g/mm and 0.25 g/mm. 
     
     
         10 . The iron-type golf club head according to  claim 1 , wherein the golf club head has a coefficient of restitution (COR) greater than 0.79. 
     
     
         11 . The iron-type golf club head according to  claim 1 , wherein a Z-up of the golf club head is below about 20 mm. 
     
     
         12 . The iron-type golf club head according to  claim 11 , wherein a Z-up of the golf club head is below about 18 mm. 
     
     
         13 . The iron-type golf club head according to  claim 1 , further comprising a channel formed in the sole portion and extending substantially parallel to the strike plate. 
     
     
         14 . The iron-type golf club head according to  claim 1 , wherein the strike plate has a minimum thickness less than or equal to 2 mm. 
     
     
         15 . The iron-type golf club head according to  claim 1 , further comprising a rear panel adjacent the bridge bar and covering the cavity, wherein the rear panel is made of a material different than the bridge bar. 
     
     
         16 . The iron-type golf club head according to  claim 15 , wherein the bridge bar is made of a metal alloy and the rear panel is made of a non-metal material having a density between 1 g/cc and 2 g/cc. 
     
     
         17 . The iron-type golf club head according to  claim 16 , wherein the non-metal material is a fiber-reinforced polymer. 
     
     
         18 . The iron-type golf club head according to  claim 1 , wherein an areal mass of the rear portion of the golf club head between the topline portion, the sole portion, the toe portion, and the heel portion is between 0.0005 g/mm 2  and 0.00925 g/mm 2 . 
     
     
         19 . An iron-type golf club head, comprising:
 a body comprising a heel portion, a sole portion, a toe portion, and a topline portion;   a strike plate coupled to the body at a front portion of the golf club head;   a cavity defined between the topline portion, the sole portion, and the strike plate; and   a bridge bar at a rear portion of the golf club head, the bridge bar spanning the cavity, spaced apart from the strike plate, and rigidly fixed to and extending uprightly between the sole portion and the topline portion, wherein:
 the bridge bar has a mass per unit length of between 0.09 g/mm and 0.40 g/mm; and 
 the bridge bar increases a frequency, at which a maximum displacement of at least one location of a plurality of locations along the topline portion occurs, by at least 100 Hz. 
   
     
     
         20 . The iron-type golf club head according to  claim 19 , wherein the bridge bar increases the frequency by at least 400 Hz. 
     
     
         21 - 23 . (canceled)