Golf ball

A golf ball being adapted to be capable of being stroked in the direction in which the center of gravity of the ball is made to coincide with the center thereof. Marks are placed on the ball to identify hit points and lead points, the hit points being those at which a first diameter line passing through the center of gravity of the ball intersects the surface of the ball and the lead points being those at which a second diameter line perpendicular to the first diameter line intersects the surface of the ball. Alternatively, marks capable of identifying the direction of the diameter line joining the hit points are set on the lead points.

FIELD OF THE INVENTION 
The present invention relates to a golf ball adapted to be hit in a 
direction in which the center of gravity of the ball is aligned with the 
geometrical center thereof by means of setting marks on the surface of the 
ball. 
DESCRIPTION OF THE PRIOR ART 
Since a golf ball may generally incur error tolerances during the 
manufacturing process, the center of gravity of the ball may not coincide 
with the geometrical central position (so-called centroid) of the ball. 
Such an occurrence produces aiming inaccuracies during use because, even 
if the ball is hit well when playing golf, the deviation of the center of 
gravity from the geometrical center causes the ball to shift during flight 
horizontally or laterally to the left or right (the direction depending 
upon the deviation of the center of gravity). In order to solve this 
problem, a Japanese prior application (Utility Model Provisional 
Publication No. SHO (58)-1465), filed by the same applicant as that of the 
present invention, discloses a golf ball provided with a circumferential 
line passing through the points at which a diameter line joining the 
geometrical center of the ball with the center of gravity intersects the 
surface of the ball. According to this Utility Model, if the ball is set 
such that the circumferential line, taken from a plan view, is aligned 
with or directed toward the target, the center of gravity of the ball will 
be positioned within a plane which includes this circumferential line and 
is aligned with the direction in which the ball is stroked by a club. This 
prevents the shift of the ball in a lateral direction caused by the 
deviation of the center of gravity enabling a user to accurately aim the 
ball during, for example, putter shots or driver shots because the path of 
the ball lies along a direction aligned with the plane of the 
circumference. 
According to the aforementioned golf ball, however, although the lateral 
shift of the ball caused by the deviation of the center of gravity can be 
prevewnted, there is an inability to maximize the range of the ball. 
Namely, if the center of gravity of the ball happens to be positioned on 
the diameter line passing through the geometrical center and if this 
diameter line is aligned with the stroke direction in which the ball is 
hit by a club head, the flying ball is shifted neither in the longitudinal 
direction nor in the vertical direction and accurately propelled with 
maximum range toward a target at which the ball is aimed. However, 
according to the foregoing Utility Model, an adequate identifying mark for 
achieving such a maximum range is not provided so that it is impossible to 
set the ball to the proper orientation to assure substantial maximization 
of range. Heretofore, it has not been possible to considerably assure that 
the direction of the diameter line passing the center of gravity of the 
ball coincides with the stroke direction. Such a defect is conspiciously 
incurred, particularly at the driver shot, thereby giving rise to one of 
the causes for the inability in attaining the maximum range. 
OBJECTS OF THE INVENTION 
The primary purpose of the present invention is to provide a golf ball 
which can make the direction of the diameter line passing the center of 
gravity of the ball coincide with the stroke direction and prevent the 
deviation of the center of gravity of the ball from shifting the flying 
direction of the ball in vertical and longitudinal directions, thereby 
enabling a user to maximize the range of the ball. 
Another purpose of the present invention is to provide a golf ball which 
can be easily oriented such that the direction of the diameter line 
passing the center of gravity of the ball is made to coincide with the 
stroke direction. 
Further purpose and advantageousness of the present invention will be 
apparent from the following description. 
SUMMARY OF THE INVENTION 
These and other objects of the present invention are achieved by a golf 
ball provided with marks utilizing hit points and lead points, said hit 
points being those points at which a first diameter line passing through 
the center of gravity of the ball intersects the surface of the ball, said 
lead points being those at which a second diameter line perpendicular to 
said first diameter line intersects the surface of the ball. A user may 
properly orient the ball for achieving maximum range and minimum lateral 
deviation by aligning the hit points and lead points in a desired manner.

DETAILED DESCRIPTION OF THE INVENTION 
Referring first to FIGS. 1 and 10, there is shown a golf ball 1 having a 
geometrical center O and a center of gravity G. The line joining the 
center of gravity G of the ball 1 with the center O is diameter line D1 
and the points at which it intersects the surface 1a of the ball 1 are the 
hit points H and H. The points at which a diameter line D2 perpendicular 
to the diameter line D1 intersects the surface 1a of the ball 1 are the 
lead points L and L. Marks 2 and 2 are put on the hit points H and H on 
the surface 1a of the ball 1. Circular marks 3 and 3 are centered on the 
lead points L and L and are extended by equal amounts toward the hit 
points H and H. 
It will be apparent that if ball 1 is set such that one circular mark 3 is 
directed upward and aligned along the direction in which ball 1 is aimed, 
the ball is oriented such that one mark 2 is on the side where the ball is 
to be hit by the club head of, for example, a driver. For this reason, a 
properly oriented shot will permit the club head to hit the end of the 
diameter line passing through center O of the ball 1 and the center of 
gravity G, thereby giving an impact to the ball 1, so that the flying 
distance of the ball 1 is proportionally expanded. That is, the more 
exactly a user orients the ball, the greater will be the range of the 
ball. A longitudinal deviation in the aimed direction, caused by the 
deviation of the center of gravity of the ball 1, is minimized and the 
ball 1 may be accurately hit to achieve the intended flight path. Proper 
orientation of the ball 1 is facilitated with reference only to circular 
marks 3 and mark 2,2. For this reason, circular mark 3 need not be a line 
and may be made simply a point provided that the mark 2 is sufficiently 
clear. Furthermore, an acceptable alternative lies not in setting the 
circular mark 3 upward but in setting the same obliquely to a player in 
response to his visual angle to the ball 1. Namely, the position of the 
circular mark 3 may be selected such that it is made easier to set the 
same, depending upon an inclination of the player. 
FIGS. 2 to 4 illustrate alternative embodiments. FIG. 2 shows the ball 4 on 
which a shortened linear mark 5 is set on the hit point H and a longer 
linear mark 6 is set on the lead point L. FIG. 3 shows the ball 7 on which 
a dashed line mark 9 is set on the circumference passing through the hit 
points H and the lead points L and a cross mark 8 is set on one or both 
hit points H. FIG. 4 shows the ball 10 on which the hit point H is 
represented by a double round mark 11 and the entire portion of the lead 
point L is represented by a circumferential mark 12. In FIG. 3 it is more 
preferable if a mark of line segment 9a is differentiated in thickness or 
color from other parts to constitute the line segment corresponding to the 
portion of line 9 intersecting lead point L. Other than the aforementioned 
marks, various kinds of marks may be adopted such as symbols, letter 
arrangements and the like, or an option in which the hit points and the 
lead points can be differentiated from each other by means of making the 
color of the marks different. Furthermore, irregular marks are also 
permissible in order to identify which of two hit points is nearer to the 
center of gravity than the other. It is also possible to make the marks 
set on the hit points H and H different from each other. 
Next, referring to FIGS. 5 to 9 illustrating other embodiments, the ball 13 
as shown in FIG. 5 is equipped on the surface 13a thereof with the 
circular mark 14 which is extended by equal amounts to each of the 
directions of the hit points H and H with the lead point L as the center. 
If the ball is set such that the circular mark 14 is directed not only 
upward but along a direction of the same flying course as aimed, the ball 
13 has a hit point H positioned to the side being hit by the club head of 
the driver. Namely, even if the aforementioned setting is made only with 
the circular mark 14 as a guide, it still enables the shot to be made in a 
direction in which the center O of the ball 13 coincides with the center 
of gravity G and the ball is ensured to be extremely naturally set. 
The ball 15 as shown in FIG. 6 equips the lead point L with an arrow mark 
16 indicating the direction of one hit point H. The arrow mark 16 may 
indicate either of the hit points H and H and it would be convenient to 
the user if one hit point H is particularly selected as used for all the 
balls 15, thereby determining the direction of the arrow mark 16. 
Furthermore, it is also acceptable that the arrow marks 16 are directed to 
both the directions, being different in shape and color from one another. 
Incidentally, the shape of the arrow mark 16 may be made to be any of 
forms including a triangular mark, a square mark, and a round mark. 
The ball 17 as shown in FIG. 7 equips the lead point L with a letter mark 
18 which arranges the letters along a circumference connecting hit points 
H and H. In that case, the letter mark 18 may, for example, stand for the 
lead point L or the maker's name or trademark. The ball 19 as shown in 
FIG. 8 equips the lead point L with multi-dot mark 20 comprising three 
point marks arranged along the circumference connecting the hit points H 
and H. The shape, color and number of dots in mark 20 is optional. The 
ball 21 as shown in FIG. 9 sets a circumferential mark 22 comprising the 
locus of the lead points L on the surface 21a of the ball, and this 
circumferential mark 22 represents that the direction perpendicular to the 
circumferential mark 22 is the diameter connecting hit points H. Under 
these embodiments further alternatives may be acceptable in which a dot 
mark is simply set as the lead point L itself, in the vicinity of which a 
direction indicating mark for showing the direction of one of the hit 
points H is set, and such an arrangement is, as a whole, adapted to show 
the position of the lead point L and the direction of one of the hit 
points H. 
Under the aforementioned embodiments of FIGS. 1 to 9, each of these marks 
may be set on any of one side or both the sides of the lead point L and 
hit point H respectively. 
According to the present invention having the foregoing construction, when 
making a shot of the ball, it is possible to make the direction of the 
diameter line passing the center of gravity of the ball coincide with the 
direction of stroke by the club head and a shift in the flight of the ball 
incurred by the deviation of the center of gravity of the ball can be 
prevented. Furthermore, a rotational moment of the ball, caused by the 
stroke, can be reduced to nil, and all the stroke force can be converted 
to the force in the aimed direction of the ball, thereby maximizing the 
range of the ball. 
In addition, because all that is required at the setting of the ball is 
simply to position the mark set on the lead point on the top of the ball 
and subsequently to aim the ball by means of the mark on the hit point or 
the mark on the lead point itself, the ball can be easily and exactly set. 
Since the player can easily discern the mark being positioned on the top 
of the ball and he has only to swing the club to make the swinging 
direction coincide with the direction indicated by the mark, he can hit 
the ball by only taking the desired range into account without the 
necessity of taking several practice swings to observe the aimed direction 
and the ball itself, thereby expecting as exact a shot as possible.