WOOD-TYPE GOLF CLUB HEAD
According to one embodiment, a wood-type golf club head includes: a face portion; a sole portion; a crown portion; a leading edge defined between the face portion and the sole portion; an upper edge defined between the face portion and the crown portion; wherein, at a basic state that the golf club head is set on a horizontal plane, a contact point between the horizontal plane and the sole portion is defined as a ground point, wherein a plane passing through the ground point and extending in a direction of a target line is defined as a vertical plane, wherein a height from the horizontal plane to a first intersection point where the face upper edge intersects the vertical plane is defined as a face height H1, and wherein a height H3 from the horizontal plane to a second intersection point where the vertical plane intersects the leading edge is defined in a range between ⅓ and ½ of the face height H1.
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This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2008-124280, filed May 12, 2008, and Japanese Patent Application No. 2007-305227, filed Nov. 27, 2007, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTIONThe present invention relates to a wood-type golf club head. In particular, the present invention relates to a golf club head for promoting, as a driver head, the increase in flight distance.
Flight distance in golf is determined by a ball initial velocity, a launch angle and a spin rate. In general, the higher the ball initial velocity, the greater the flight distance, and there exist a launch angle and a spin rate which make the most of the ball initial velocity. On the other hand, the current golf ball development aims at improvement of ball initial velocity and lower spin (reduction in spin rate) in order to obtain longer flight. More specifically, it is said that, current balls have spin rates too high to hit a long ball, and it is also said that a combination of current golf club and golf ball does not realize a launch angle and a spin rate which make the most of a ball initial velocity.
As one of golf club design techniques concerning flight, there is a technique for optimizing a launch angle and a spin rate by utilizing gear effect resulting from the specialty of a wood-type golf club head, which has a deep center of gravity. The launch angle and spin rate at each position on a hitting plane (face) are determined by a loft angle at this point (each position); however, in the face design of a wood club head, a loft angle at each point of the face is determined so as to provide the launch angle and spin rate at which the flight distance is maximized, and then, upon connecting each point of the face vertically so that the determined loft angle at each point of the face becomes tangential, a curve is formed longitudinally, which is a roll design. In other words, this technique is a face roll design technique provided in consideration of impact factors such as the center of gravity and moments of inertia. Further, in a head of a wood-type golf club, having a deep center of gravity, a position at which the maximum flight is obtained is generally located above a perpendicular line drawn from the center of gravity of the head onto a face plane as shown in
On the other hand, in view of hitting points of golfers, most of professional and advanced golfers each apparently hit a ball with a face center at the sight of their club faces. Among them, there are some golfers who empirically know that the maximum flight point is located above the face center, but the aim of the hitting point in a stable game is hitting of the face center. Next,
Moreover,
In a wood-type golf club head disclosed in each of JP-A-H07-178207 and JP-A-2000-262657, an intersection point of a perpendicular line from the center of gravity with respect to a face plane, i.e., a sweet spot, is to be located at the center of the face plane (face center); however, the head has an unusual shape such as a vault shape or a potbellied shape, and a golfer has felt the difficulty of coming to the ready because of the unduly peculiar shape when the golfer has seen the head from above at address.
SUMMARY OF THE INVENTIONAccording to an aspect of the present invention, there is provided a golf glove including: a main body that includes a palm side portion and a back side portion, the palm side portion being configured to closely fit to a palm of a hand of a golfer, the back side portion being configured to closely fit to a back side of the hand; a first slip preventive element placed at least on a first area that is interior of a grip receiving area on an outer surface of the main body, where a grip portion of a golf club is in contact with the main body when the golfer grips the golf club; wherein the first slip preventive element has a larger slip resistance to sweat of the hand and water coming into an inside of the golf glove than the main body.
According to another aspect of the present invention, there is provided a golf glove including: a main body that includes a palm side portion and a back side portion, the palm side portion being configured to closely fit to a palm of a hand of a golfer, the back side portion being configured to closely fit to a back side of the hand; a second slip preventive element placed on a second area that is interior of an intermediate portion area in the main body, the intermediate area being positioned at a substantially intermediate between a lowermost position of a little finger portion of the main body and a wrist portion of the main body, so as to extend from the palm side portion to the back side portion; wherein the second slip preventive element is made of a porous elastic resin film.
According to another aspect of the present invention there is provided a golf glove including: a main body that includes a palm side portion and a back side portion, the palm side portion being configured to closely fit to a palm of a hand of a golfer, the back side portion being configured to closely fit to a back side of the hand; a third slip preventive element including a traversing portion and a lower portion, the traversing portion placed on an interior of the palm side portion so as to traverse bases of finger portions except thumb portion in the main body, the lower portion placed on the interior of the palm side portion so as to extend along a life line on the palm of the golfer in a direction reverse to an extending direction of the life line; wherein the third slip preventive element is made of a resin foam film.
According to another aspect of the present invention there is provided a golf glove including: a main body that includes a palm side portion and a back side portion, the palm side portion being configured to closely fit to a palm of a hand of a golfer, the back side portion being configured to closely fit to a back side of the hand, the back side portion including an access opening formed at a lower position thereof; a locking belt that is sewn to the back side, the locking belt for closing the access opening; a forth slip preventive element placed on a forth area that is interior of the back side portion, the forth area extending from a lowermost position of an index finger portion of the back side portion toward the locking belt, the forth slip preventive element including minute projections and made of an artificial leather.
In this way, the invention is characterized in that the preventive elements which exhibit the high resistance to slip relative to water secreted from the hand of the golfer and water which penetrates into the golf glove in wet weather are affixed to the specific locations on the inner surface of at least the portions on the palm side area or the back side area of the glove main body with which the grip portion of the golf club is brought into abutment, whereby the stable grip is obtainable under every condition, thereby making it possible to prevent effectively an error in hitting a ball.
These and other object and advantages of this invention will become more fully apparent from the following detailed description taken with the accompanying drawings in which:
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
The height H3 may be defined as ⅙ to ½ of the face height H1, or may be defined as ⅛ to ½ thereof. The height H3 is defined as ½ of the face height H1 at the maximum.
A portion adjacent to a chamfered portion is formed into a convex curved surface shape in
In
Each of the embodiments shown in
In general, if a titanium alloy head is designed to have a head volume of 300 cc or more and a face thickness of 3 mm or less, such a design runs counter to the SLE (Spring Like Effect) rule. However, when the chamfer height is raised and the width of the face is reduced in this manner, it becomes difficult for the face to cause deflection, and it is unnecessary to provide a special structure, thus making the cost reasonable. Moreover, until now, the position at which a ball flies farthest (which is located above a sweet spot), and the position of the center of gravity of the face, or the most deflective position of the face have been greatly deviated from each other; however, the adoption of the present method can fly the ball more efficiently. Furthermore, the present invention is implemented as a hollow metal golf club head in which, in particular, a titanium alloy, an aluminum alloy or the like is used as a metal material, and a crown portion and a sole portion each have a thickness of 0.5 mm to 2 mm, preferably 0.7 mm to 1.2 mm. The sole portion has a generally uniform large round, and the round measures about 80 mm to about 125 mm from the toe side to the heel side. On the other hand, in the case of a raised sole, the raised part is solid, and the lowermost portion thereof is preferably formed by a material having a specific gravity greater than that of the head body.
As described with reference to the embodiment, there is provided a wood-type golf club head that eliminates the difficulty of coming to the ready at address, and allows a face center to serve as a maximum flight distance point.
According to the embodiment, when a head body is set on a horizontal plane, a height measured to an intersection point of a face upper edge and a vertical plane, passing through a ground point between this horizontal plane and a sole of the head body and extending from the rear of the head in a target line direction serving as a target, is defined as a face height, and a height measured to an intersection point of the vertical plane and a leading edge is defined as ⅓ to ½ of the face height; thus, if a clear face area is indicated, a professional or advanced golfer who has a high technique of stable hitting with the face center can obtain a maximum flight distance by hitting with the center of the face (face center) because he or she has the technique to hit with the center. Furthermore, when the head is seen from above at address, it has the similar shape as a conventional head, thus preventing the drawback of causing the difficulty of coming to the ready.
Moreover, in the embodiment in which, when the head body is set on the horizontal plane, there is provided an edge line of at least one second sole located 5 to 20 mm below a sole plane extending from the lowermost point of a chamfered surface in the direction opposite to the target line direction, via a plane or a convex curved surface, i.e., a so-called chamfer, extending downward from the lowermost point of the head body and in the direction opposite to the target line direction, it is possible to make the face center coincide with the maximum flight distance point, and to increase the flight distance. Besides, the head appearance has an unprecedentedly peculiar shape that attracts the attention of a bystander, but a golfer who uses this head does not feel the peculiar shape at address.
Claims
1. A wood-type golf club head comprising:
- a face portion;
- a sole portion;
- a crown portion;
- a leading edge defined between the face portion and the sole portion;
- an upper edge defined between the face portion and the crown portion;
- wherein, at a basic state that the golf club head is set on a horizontal plane, a contact point between the horizontal plane and the sole portion is defined as a ground point,
- wherein a plane passing through the ground point and extending in a direction of a target line is defined as a vertical plane,
- wherein a height from the horizontal plane to a first intersection point where the face upper edge intersects the vertical plane is defined as a face height H1, and
- wherein a height H3 from the horizontal plane to a second intersection point where the vertical plane intersects the leading edge is defined in a range between ⅓ and ½ of the face height H1.
2. The wood-type golf club head according to claim 1, wherein the height H3 is defined in a range between ⅙ and ½ of the face height H1.
3. The wood-type golf club head according to claim 1, wherein the height H3 is defined in a range between ⅛ and ½ of the height H1.
4. The wood-type golf club head according to claim 1, wherein a third intersection point where the face portion intersects a perpendicular line drawn from a center of gravity of the golf club head onto the face portion is lower than a face center FC of the face portion, the face center FC being defined as
- FC=(H1−H3)/2+H3.
5. The wood-type golf club head according to claim 1 further comprising a chamfer portion formed between the leading edge and the sole portion,
- wherein the sole portion includes a first sole portion and a second sole portion including the ground point,
- wherein a height H0 from the horizontal plane to the ground point is lower than a height H4 from the horizontal plane to a lowermost portion of the first sole portion, and
- wherein the height H0 is lower than a height from the horizontal plane to a lowermost point of the chamfered portion;
6. The wood-type golf club head according to claim 5, wherein the height H4 is in a range from 5 mm to 20 mm.
7. The wood-type golf club head according to claim 5, wherein a height H5 from the leading edge to the lowermost portion of the first sole portion is in a range from 2 mm to 5 mm.
8. The wood-type golf club head according to claim 5, wherein the chamfered portion is extend downward from the leading edge and in a direction opposite to the target line direction.
Type: Application
Filed: Sep 17, 2008
Publication Date: May 28, 2009
Applicant: BRIDGESTONE SPORTS CO., LTD. (Tokyo)
Inventor: Ryota KAJITA (Tokyo)
Application Number: 12/212,223
International Classification: A63B 53/04 (20060101);