Source: https://patents.google.com/patent/US7018303B2/en
Timestamp: 2019-07-20 11:55:04
Document Index: 406584014

Matched Legal Cases: ['art 9', 'art 9', 'art 9', 'art 9', 'art 9', 'art 10', 'art 9', 'art 9', 'art 10', 'art 9', 'art 9', 'art 10', 'art 9', 'art 10', 'art 10', 'arts 9', 'arts 9', 'arts 10', 'arts 9', 'arts 10', 'arts 9', 'art 10', 'arts 9', 'arts 10', 'art 9', 'art 9', 'art 9', 'arts 9']

US7018303B2 - Golf clubhead - Google Patents
US7018303B2
US7018303B2 US10/246,668 US24666802A US7018303B2 US 7018303 B2 US7018303 B2 US 7018303B2 US 24666802 A US24666802 A US 24666802A US 7018303 B2 US7018303 B2 US 7018303B2
annular thin
US10/246,668
US20030064823A1 (en
2001-09-28 Priority to JP2001-302381 priority Critical
2001-09-28 Priority to JP2001302381A priority patent/JP3895571B2/en
2002-09-19 Application filed by SRI Sports Ltd filed Critical SRI Sports Ltd
2002-09-19 Assigned to SUMITOMO RUBBER INDUSTRIES, LTD. reassignment SUMITOMO RUBBER INDUSTRIES, LTD. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: YAMAMOTO, AKIO
2003-04-03 Publication of US20030064823A1 publication Critical patent/US20030064823A1/en
2006-03-28 Publication of US7018303B2 publication Critical patent/US7018303B2/en
A golf clubhead comprises a face portion having a back surface which is provided around a center region with at least two annular grooves so that the face portion is provided with at least two annular thin parts each being thinner than the center region and at least one rib part between the thin parts, whereby the rebound performance and durability of the face portion can be improved.
The present invention relates to a golf clubhead more particularly to a face portion being capable of improving the rebound performance and durability.
It is therefore, an object of the present invention to provide a golf clubhead in which the face portion is improved in the durability as well as the rebound performance.
FIG. 1 is a front view of a clubhead according to the present invention.
FIG. 3 a is a cross sectional view of the face portion thereof taken along a line A—A in FIG. 1.
FIG. 3 b is a cross sectional view of the same face portion taken along a line B—B in FIG. 1.
FIGS. 5 a and 5 b are cross sectional views of another example of the face portion taken along a line A—A and a line B—B in FIG. 1, respectively.
FIGS. 6 a and 6 b are cross sectional views of another example of the face portion taken along a line A—A and a line B—B in FIG. 1, respectively.
FIGS. 7 a and 7 b are cross sectional views of the face portion of a comparative example taken along a line A—A and a line B—B in FIG. 1, respectively.
FIGS. 8 a and 8 b are cross sectional views of the face portion of another comparative example taken along a line A—A and a line B—B in FIG. 1, respectively.
FIGS. 9 a and 9 b are cross sectional views of the face portion of another comparative example taken along a line A—A and a line B—B in FIG. 1, respectively, and FIG. 9 c shows the thickness distribution thereof.
The face portion 2 is provided on the back surface 7 with annular grooves to provide the face portion with a first annular thin part 9 a having a thickness (ta), a second annular thin part 9 b having a thickness (tb) and a third annular thin part 9 c having a thickness (tc) (hereinafter, generically the “annular thin part 9” and “thickness t”). The thickness (t) is less than the thickness To of a center region Ac which is defined as being surrounded and enclosed by the innermost first annular thin part 9 a. Here, the thickness (t) means the thickness at the thinnest position of the part concerned.
On the other hand, by providing the annular grooves, annular rib parts are formed. In this embodiment, the rib parts include: a first rib part 10 a between the first annular thin part 9 a and second annular thin part 9 b having a thickness Ta more than the thickness (ta); a second rib part 10 b between the second annular thin part 9 b and third annular thin part 9 c having a thickness Tb more than the thickness (tb); and a third rib part 10 c outside the third annular thin part 9 c having a thickness Tc more than the thickness (tc), (hereinafter the “rib part 10” having the “thickness T”.) Here, the thickness T is defined as the thickness at the thickest position of the rib 10. The rib part 10 is continuous and annular.
The center region Ac has a thickness To in a range of from 2.2 to 3.2 mm. More preferably 2.5 to 2.8 mm, in this embodiment, almost constant value of 2.8 mm.
The thickness (ta) is in a range of from 2.1 to 2.8 mm, more preferably 2.4 to 2.6 mm.
The thickness (tb) is not more than, preferably less than the thickness (ta). More specifically, the thickness (tb) is in a range of from 1.8 to 2.5 mm, more preferably 2.1 to 2.3 mm.
The thickness (tc) is not more than, preferably less than the thickness (tb). More specifically, the thickness (tc) is in a range of from 1.5 to 2.2 mm, more preferably 1.8 to 2.0 mm.
Thus, it is preferable that the thickness (t) gradually decreases from the innermost thin part to the outmost thin part.
On the other hand, the thickness T (Ta, Tb, Tc) in this embodiment is the substantially same as the thickness To of the center region Ac, but, it is also possible to gradually change the thickness T from the center towards the periphery of the clubface F such that Ta>Tb>Tc.
If the thickness To is less than 2.2 mm, the center region Ac is liable to be broken by impact force at the time of striking a ball. If the thickness To is more than 3.2 mm, as the face portion becomes rigid in its entirety, it is difficult to improve the rebound performance.
Further, the intervals P between the annular thin parts 9 are set in a range of from 5 to 20 mm, preferably 5 to 15 mm, more preferably 5 to 10 mm. The intervals P are changed around the clubface center Fc such that the intervals P are larger on the toe-side and heel-side (horizontal direction) but smaller on the crown-side and sole-side (vertical direction). As the intervals P vary around the clubface center Fc, the interval P is defined as the distance measured between the centers of the annular thin parts along a straight line S passing the clubface center Fc—the straight line S may extend in every direction (360 deg.). It is preferable that intervals P along each straight line S extending from the clubface center Fc to the clubface edge (E) are substantially constant, although the widths W are not always constant.
In case of short pitch P (in such a direction, for example in the vertical direction), in a cross section of the face portion 2 in such direction, the annular thin parts 9 and rib parts 10 are formed by a curved line like a sine curve as shown in FIG. 3 b. In case of long pitch P (in such a direction, for example in the horizontal direction), in a cross section of the face portion 2 in such direction, the annular thin parts 9 and rib parts 10 are formed by a curved line like a hybrid of a sine wave and a trapezoidal wave as shown in FIG. 3 a. specifically, the annular thin parts 9 is a sine wave and the rib part 10 is a trapezoidal wave.
Further, if the pitch P is more long and the width W is more wide, as shown in FIG. 4, the groove bottom may have a flat part, the groove sidewalls are inclined outside, and the rib part may have a flat part.
FIGS. 5 a and 5 b shows another example of the face portion 2, wherein the change in the thickness of the face portion 2 is stepped contrary to the above-mentioned example. In a cross section of the face portion 2, the annular thin parts 9 and rib parts 10 are formed by a polygonal line like a rectangular wave.
Furthermore, as to the width (W) of the annular thin part 9, each annular thin part 9 in this embodiment is wider on the toe-side and heel-side, but narrower on the crown-side and sole-side. And the width changes smoothly or continuously between the wide parts and narrow parts. As the width (W) of the annular thin part 9 vary around the clubface center Fc, the width is defined as being measured along a straight line S passing the clubface center Fc—the straight line may extend in every direction (360 deg.). Further, in case of the rounded corners as shown in FIG. 4, the width (W1,W2,W3) may be defined as a distance between virtual corners (e) between the back surface 7 and groove sidewall.
If the widths W1, W2 and W3 are less than 1.7 mm, 1.5 mm and 1.3 mm, respectively, it becomes difficult to effectively decrease the rigidity to improve the rebound performance. if the widths W1, W2 and W3 are more than 5.4 mm, 5.4 mm and 5.0 mm, respectively, the face portion 2 is liable to decrease in the durability.
Further, for the purpose of improving the flexibility of the face portion without decreasing the durability, the widths W1, W2 and W3 of the annular thin parts 9 a, 9 b and 9 c may be gradually increased from the center towards the outside (namely, W1<W2<W3). This magnitude relation is mentioned on the widths along the above-mentioned straight line S extending from the clubface center Fc to the edge E of the clubface F.
As specified therein, the golf balls used were “Titleist, PINNACLE GOLD” and the radius of the target circle centered on the sweet spot was 5 mm. The distance between the clubface and the launching device was 55 inches, and the incoming ball velocity was 160±0.5 feet/sec.
Clubhead Ex. 1 Ex. 2 Ex. 3 Ex. 4 Ex. 5 Ex. 6 Ex. 7 Ex. 8 Ref. 1 Ref. 2 Ref. 3
Structure FIG. 3 FIG. 5 FIG. 3 FIG. 3 FIG. 6 FIG. 3 FIG. 3 FIG. 3 FIG. 7 FIG. 8 FIG. 9
Thickness To (mm) 2.8 2.8 2.8 2.8 2.8 2.8 2.8 2.8 2.8
Length x (mm) 10 10 10 8 22 10 10 10 37
Length y (mm) 20 20 20 15 61 20 20 20 76
Number 3 3 3 3 2 3 3 3 1 — —
Thickness ta (mm) 2.5 2.5 2.2 2.5 2.5 2.0 2.4 2.6 2.2
Thickness tb (mm) 2.2 2.2 2.5 2.2 2.5 2.2 2.1 2.3 —
Thickness tc (mm) 2.0 2.0 2.0 2.0 2.0 2.5 1.8 2.0 —
x-direction (mm) 11 7 11 9 11 11 11 11 —
y-direction (mm) 5 5 5 4 5 5 5 5 —
Remarks smooth stepped t2 > t3 smaller t1 < t2 < t3 thinner thicker conven-
thickness thickness center tional
change change region
Restitution coefficient 0.835 0.835 0.832 0.835 0.821 0.825 0.837 0.834 0.810 0.825 0.840
Durability 520 200 390 380 600 150 490 550 520 380 120
US10/246,668 2001-09-28 2002-09-19 Golf clubhead Expired - Fee Related US7018303B2 (en)
JP2001-302381 2001-09-28
JP2001302381A JP3895571B2 (en) 2001-09-28 2001-09-28 Golf club head
US20030064823A1 US20030064823A1 (en) 2003-04-03
US7018303B2 true US7018303B2 (en) 2006-03-28
ID=19122632
US10/246,668 Expired - Fee Related US7018303B2 (en) 2001-09-28 2002-09-19 Golf clubhead
US (1) US7018303B2 (en)
JP (1) JP3895571B2 (en)
JP6095348B2 (en) * 2012-12-07 2017-03-15 ブリヂストンスポーツ株式会社 Golf club head
JP2813969B2 (en) 1995-05-19 1998-10-22 亨 高村 Golf club
2001-09-28 JP JP2001302381A patent/JP3895571B2/en active Active
2002-09-19 US US10/246,668 patent/US7018303B2/en not_active Expired - Fee Related
JP3895571B2 (en) 2007-03-22
JP2003102879A (en) 2003-04-08
US20030064823A1 (en) 2003-04-03
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:YAMAMOTO, AKIO;REEL/FRAME:013303/0789