Golf club heads with slits and flexure inserts

Abstract

Described herein are embodiments of golf club heads with slits and flexure inserts. The slit comprises an opening through the club head body communicating between the exterior of the club head and the hollow interior cavity. The flexure insert can comprise a spring component and a cap. The spring component creates a spring effect within the flexure insert that increases the internal energy of the club head at impact, leading to improvements in ball speed and other golf ball performance characteristics.

1 . A golf club head comprising:
 a strike face comprising a striking surface for impacting a golf ball;   a body comprising a crown, a sole, a heel, a toe, and a rear end;   wherein the strike face and body are configured to be secured together to enclose a hollow interior cavity;   the sole defines a slit proximate the strike face, wherein the slit provides an opening communicating between the hollow interior cavity and an exterior of the golf club head;   the slit comprising a front surface and a rear surface;   a flexure insert disposed within the slit, the flexure insert comprising:
 a spring component formed of a first material having a first modulus of elasticity; and 
 a cap formed of a second material having a second modulus of elasticity that is less than the first modulus of elasticity; 
   wherein the spring component comprises:
 a front arm configured to engage the front surface of the slit and has a front arm top end and a front arm bottom end; 
 a rear arm configured to the engage the rear surface of the slit having a rear arm top end and a rear arm bottom end; and 
 a cross arm extending diagonally between the front arm top end and the rear arm bottom end to form an N-shaped configuration. 
   
     
     
         2 . The golf club head of  claim 1 , wherein the first material is selected from the group consisting of plastic, composite thermoset, steel, stainless steel, spring steel, titanium, and aluminum. 
     
     
         3 . The golf club head of  claim 1 , wherein the first modulus of elasticity is between 20 GPa and 210 GPa. 
     
     
         4 . The golf club head of  claim 1 , wherein the second material is an injection molded polymer. 
     
     
         5 . The golf club head of  claim 1 , wherein the second modulus of elasticity is between 0.1 GPa and 30 GPa. 
     
     
         6 . The golf club head of  claim 1 , wherein the cross arm and the front arm form a front joint angle, and the cross arm and the rear arm form a rear joint angle; the front joint angle and the rear joint angle are between 25 and 65 degrees. 
     
     
         7 . The golf club head of  claim 6 , wherein the spring component is located within a central portion of the slit, and the heel and toe portions of the slit are devoid of the spring component. 
     
     
         8 . The golf club head of  claim 1 , wherein:
 the slit comprises a slit length measured as a heel-to-toe distance between a heel most point of the slit to a toe most point of the slit;   the spring component comprises a spring component length that is a heel-to-toe distance from a heel most point of the spring component to a toe most point of the spring component;   wherein the spring component length is between 10% and 50% of the slit length.   
     
     
         9 . The golf club head of  claim 8 , wherein the cap comprises a thickness greater in the heel and the toe than in a central portion. 
     
     
         10 . The golf club head of  claim 1 , wherein the cap comprises an injection molded polymer selected from the group consisting of TPE, TPU, silicone, and butyl rubber. 
     
     
         11 . A golf club head comprising:
 a strike face comprising a striking surface for impacting a golf ball;   a body comprising a crown, a sole, a heel, a toe, and a rear end;   wherein the strike face and body are configured to be secured together to enclose a hollow interior cavity;   the sole defines a slit proximate the strike face, wherein the slit provides an opening communicating between the hollow interior cavity and an exterior of the golf club head;   the slit comprising a front surface and a rear surface;   a flexure insert disposed within the slit, the flexure insert comprising:
 a spring component formed of a first material having a first modulus of elasticity; and 
 a cap formed of a second material having a second modulus of elasticity that is less than the first modulus of elasticity; 
   wherein the spring component comprises:
 a front arm configured to engage the front surface of the slit and has a front arm top end and a front arm bottom end; 
 a rear arm configured to the engage the rear surface of the slit having a rear arm top end and a rear arm bottom end; and
 a cross arm extending diagonally between the front arm bottom end and the rear arm top end. 
 
   
     
     
         12 . The golf club head of  claim 11 , wherein the first material is selected from the group consisting of plastic, composite thermoset, steel, stainless steel, spring steel, titanium, and aluminum. 
     
     
         13 . The golf club head of  claim 11 , wherein the first modulus of elasticity is between 20 GPa and 210 GPa. 
     
     
         14 . The golf club head of  claim 11 , wherein the second material is an injection molded polymer. 
     
     
         15 . The golf club head of  claim 11 , wherein the second modulus of elasticity is between 0.1 GPa and 30 GPa. 
     
     
         16 . The golf club head of  claim 11 , wherein the cross arm and the front arm form a front joint angle, and the cross arm and the rear arm form a rear joint angle; the front joint angle and the rear joint angle are between 25 and 65 degrees. 
     
     
         17 . The golf club head of  claim 16 , wherein the spring component is located within a central portion of the slit, and the heel and toe portions of the slit are devoid of the spring component. 
     
     
         18 . The golf club head of  claim 11 , wherein:
 the slit comprises a slit length measured as a heel-to-toe distance between a heel most point of the slit to a toe most point of the slit;   the spring component comprises a spring component length that is a heel-to-toe distance from a heel most point of the spring component to a toe most point of the spring component;   wherein the spring component length is between 10% and 50% of the slit length.   
     
     
         19 . The golf club head of  claim 18 , wherein the cap comprises a thickness greater in the heel and the toe than in a central portion. 
     
     
         20 . The golf club head of  claim 11 , wherein the cap comprises an injection molded polymer selected from the group consisting of TPE, TPU, silicone, and butyl rubber.