Golf club head having a stress reducing feature with aperture
A golf club incorporating a stress reducing feature, including an aperture, located at least partially on the sole of the club head. The location and size of the stress reducing feature and aperture, and their relationship to one another, play a significant role in selectively improving the performance of the golf club.
1. A hollow golf club having a stress reducing feature with aperture comprising:
(A) a shaft ( 200 ) having a proximal end ( 210 ) and a distal end ( 220 );
(B) a grip ( 300 ) attached to the shaft proximal end ( 210 ); and
(C) a golf club head ( 400 ) attached to the shaft distal end ( 220 ) and having:
(i) a face ( 500 ) positioned at a front portion ( 402 ) of the golf club head ( 400 ) where the golf club head ( 400 ) impacts a golf ball, and wherein the face ( 400 ) includes a top edge height (TEH) and a lower edge height (LEH);
(ii) a sole ( 700 ) positioned at a bottom portion of the golf club head ( 400 );
(iii) a crown ( 600 ) positioned at a top portion of the golf club head ( 400 );
(iv) a skirt ( 800 ) positioned around a portion of a periphery of the golf club head ( 400 ) between the sole ( 700 ) and the crown ( 600 ), wherein the face ( 500 ), sole ( 700 ), crown ( 600 ), and skirt ( 800 ) define an outer shell that further defines a head volume, and wherein the golf club head ( 400 ) has a rear portion ( 404 ) opposite the face ( 500 );
(v) a bore having a center that defines a shaft axis (SA) which intersects with a horizontal ground plane (GP) to define an origin point, wherein the bore is located at a heel side ( 406 ) of the golf club head ( 400 ) and receives the shaft distal end ( 220 ) for attachment to the golf club head ( 400 ), and wherein a toe side ( 408 ) of the golf club head ( 400 ) is located opposite of the heel side ( 406 );
(vi) a center of gravity (CG) of the golf club head ( 400 ) located:
(a) vertically toward the crown ( 600 ) of the golf club head ( 400 ) from the origin point a distance Ycg;
(b) horizontally from the origin point toward the toe side ( 408 ) of the golf club head ( 400 ) a distance Xcg that is generally parallel to the face ( 500 ) and the ground plane (GP); and
(c) a distance Zcg from the origin toward the rear portion ( 404 ) in a direction generally orthogonal to the vertical direction used to measure Ycg and generally orthogonal to the horizontal direction used to measure Xcg;
(vii) a stress reducing feature ( 1000 ) including a sole located SRF ( 1300 ) located at least partially on the sole ( 700 ), wherein:
(a) the sole located SRF ( 1300 ) has a SSRF length ( 1310 ) between a SSRF toe-most point ( 1312 ) and a SSRF heel-most point ( 1316 ), a SSRF leading edge ( 1320 ) having a SSRF leading edge offset ( 1322 ), a SSRF trailing edge ( 1330 ), a SSRF volume, a SSRF width ( 1340 ), and a SSRF depth ( 1350 ), wherein the sole located SRF ( 1300 ) has at least one of (a) a portion of the SSRF width ( 1340 ) is at least ten percent of the Zcg distance, and (b) a portion of the SSRF depth ( 1350 ) is at least ten percent of the Ycg distance; and
(b) the sole located SRF ( 1300 ) has a SSRF aperture ( 1400 ) recessed from the sole ( 700 ) and extending through the outer shell, wherein the SSRF aperture ( 1400 ) has a SSRF aperture length ( 1410 ) between a SSRF aperture toe-most point ( 1412 ) and a SSRF aperture heel-most point ( 1416 ), and a SSRF aperture width ( 1440 ), wherein the SSRF aperture length ( 1410 ) is at least fifty percent of the Xcg distance; and
(c) the golf club head ( 400 ) has a characteristic time of at least 220 microseconds.
2. The golf club of claim 1 , wherein the golf club head ( 400 ) includes a blade length (BL) measured horizontally from the origin point toward the toe side ( 408 ) of the golf club head ( 400 ) to the most distant point on the golf club head in this direction, wherein the blade length (BL) includes:
(a) a heel blade length section (Abl) measured in the same direction as the blade length (BL) from the origin point to an engineered impact point (EIP);
(b) a toe blade length section (Bbl); wherein
(c) the SSRF length ( 1310 ) and the SSRF aperture length ( 1410 ) are at least as great as the heel blade length section (Abl).
3. The golf club of claim 2 , wherein the SSRF length ( 1310 ) and the SSRF aperture length ( 1410 ) are at least 50% of the blade length (BL).
4. The golf club of claim 2 , wherein the face ( 400 ) has a face thickness that varies from a minimum thickness of at least 0.050″ to a maximum thickness that is at least 25% greater than the minimum thickness.
5. The golf club of claim 4 , wherein the SSRF aperture width ( 1440 ) of the SSRF aperture ( 1400 ) is less than the maximum face thickness.
6. The golf club of claim 5 , wherein the SSRF aperture width ( 1440 ) of at least a portion of the SSRF aperture ( 1400 ) is at least fifty percent of the minimum face thickness.
7. The golf club of claim 2 , wherein at least a portion of the SSRF aperture ( 1400 ) is horizontally separated from the SSRF trailing edge ( 1330 ) by a separation distance that is at least ten percent of the Zcg distance.
8. The golf club of claim 2 , wherein the SSRF volume is at least 1% of the head volume.
9. The golf club of claim 8 , wherein the SSRF volume is no more than 5% of the head volume.
10. The golf club of claim 2 , wherein a portion of the outer shell has a density of less than 5 g/cm 3 .
11. The golf club of claim 10 , wherein the portion of the outer shell has the density of less than 5 g/cm 3 is a nonmetallic composite.
12. The golf club of claim 10 , wherein the Ycg distance is less than 0.65″.
13. The golf club of claim 1 , wherein the head volume is less than 300 cubic centimeters, the face ( 500 ) has a loft of at least 12 degrees and a face height between the maximum top edge height (TEH) and the minimum lower edge (LEH) is less than 1.50″.
14. The golf club of claim 13 , wherein a club moment arm (CMA) from the CG to an engineered impact point (EIP) is less than 1.1″, and a transfer distance (TD) is least 10 percent greater than the club moment arm (CMA).
15. The golf club of claim 14 , wherein the transfer distance (TD) is no more than 40 percent greater than the club moment arm (CMA).
16. The golf club of claim 1 , wherein at least a portion of the SSRF aperture ( 1400 ) is located above the lower edge height (LEH).
17. The golf club of claim 16 , wherein the SSRF aperture ( 1400 ) is located at a SSRF aperture depth ( 1450 ) measured vertically from the lower edge height (LEH) toward the center of gravity (CG), and the SSRF aperture depth ( 1450 ) of at least a portion of the SSRF aperture ( 1400 ) is greater than zero.
18. A hollow golf club having a stress reducing feature with aperture comprising:
(A) a shaft ( 200 ) having a proximal end ( 210 ) and a distal end ( 220 );
(B) a grip ( 300 ) attached to the shaft proximal end ( 210 ); and
(C) a golf club head ( 400 ) attached to the shaft distal end ( 220 ) and having:
(i) a face ( 500 ) positioned at a front portion ( 402 ) of the golf club head ( 400 ) where the golf club head ( 400 ) impacts a golf ball, and wherein the face ( 400 ) includes a top edge height (TEH) and a lower edge height (LEH), and the face ( 400 ) has a face thickness that varies from a minimum thickness of at least 0.050″ to a maximum thickness;
(ii) a sole ( 700 ) positioned at a bottom portion of the golf club head ( 400 );
(iii) a crown ( 600 ) positioned at a top portion of the golf club head ( 400 );
(iv) a skirt ( 800 ) positioned around a portion of a periphery of the golf club head ( 400 ) between the sole ( 700 ) and the crown ( 600 ), wherein the face ( 500 ), sole ( 700 ), crown ( 600 ), and skirt ( 800 ) define an outer shell that further defines a head volume, and wherein the golf club head ( 400 ) has a rear portion ( 404 ) opposite the face ( 500 );
(v) a bore having a center that defines a shaft axis (SA) which intersects with a horizontal ground plane (GP) to define an origin point, wherein the bore is located at a heel side ( 406 ) of the golf club head ( 400 ) and receives the shaft distal end ( 220 ) for attachment to the golf club head ( 400 ), and wherein a toe side ( 408 ) of the golf club head ( 400 ) is located opposite of the heel side ( 406 );
(vi) a center of gravity (CG) of the golf club head ( 400 ) located:
(a) vertically toward the crown ( 600 ) of the golf club head ( 400 ) from the origin point a distance Ycg;
(b) horizontally from the origin point toward the toe side ( 408 ) of the golf club head ( 400 ) a distance Xcg that is generally parallel to the face ( 500 ) and the ground plane (GP); and
(c) a distance Zcg from the origin toward the rear portion ( 404 ) in a direction generally orthogonal to the vertical direction used to measure Ycg and generally orthogonal to the horizontal direction used to measure Xcg;
(vii) a stress reducing feature ( 1000 ) including a sole located SRF ( 1300 ) located at least partially on the sole ( 700 ), wherein:
(a) the sole located SRF ( 1300 ) has a SSRF length ( 1310 ) between a SSRF toe-most point ( 1312 ) and a SSRF heel-most point ( 1316 ), a SSRF leading edge ( 1320 ) having a SSRF leading edge offset ( 1322 ), a SSRF trailing edge ( 1330 ), a SSRF volume, a SSRF width ( 1340 ), and a SSRF depth ( 1350 ), wherein the sole located SRF ( 1300 ) has at least one of (a) a portion of the SSRF width ( 1340 ) is at least ten percent of the Zcg distance, and (b) a portion of the SSRF depth ( 1350 ) is at least ten percent of the Ycg distance; and
(b) the sole located SRF ( 1300 ) has a SSRF aperture ( 1400 ) recessed from the sole ( 700 ) and extending through the outer shell, wherein the SSRF aperture ( 1400 ) has a SSRF aperture length ( 1410 ) between a SSRF aperture toe-most point ( 1412 ) and a SSRF aperture heel-most point ( 1416 ), and a SSRF aperture width ( 1440 ) that is less than the maximum face thickness, wherein the SSRF aperture length ( 1410 ) is at least fifty percent of the Xcg distance; and
(c) the golf club head ( 400 ) has a characteristic time of at least 220 microseconds.
19. The golf club of claim 18 , wherein at least a portion of the SSRF aperture ( 1400 ) is horizontally separated from the SSRF trailing edge ( 1330 ) by a separation distance that is at least ten percent of the Zcg distance.
20. The golf club of claim 18 , wherein the head volume is less than 300 cubic centimeters, the face ( 500 ) has a loft of at least 12 degrees and a face height between the maximum top edge height (TEH) and the minimum lower edge (LEH) is less than 1.50″.