# Patent

## Title
Set of golf clubs

## Abstract

A set of golf club heads having peripheral weights that change from club head to club head so that the center of gravity rises from the long irons to the short irons resulting in a consistent peak trajectory height along a line for each club head.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of U.S. patent application Ser. No. 09/603,891, filed Jun. 26, 2000, now U.S. Pat. No. 6,482,104, which is a continuation-in-part of U.S. patent application Ser. No. 09/285,711, filed Apr. 5, 1999, now U.S. Pat. No. 6,290,607, the entire disclosures of which are incorporated by reference herein.


FIELD OF THE INVENTION
The present invention generally relates to sets of golf clubs, and more particularly, to a set of golf club irons that provide a more consistent ball flight peak trajectory height along a line and having a center of gravity that varies for each iron in the set.
BACKGROUND OF THE INVENTION
In conventional sets of “iron” golf clubs, each club includes a shaft with a club head attached to one end and a grip attached to the other end. The club head includes a face for striking a golf ball. The angle between the face and a vertical plane is called “loft.”
The set generally includes irons that are designated number 1 through number 9, and a series of wedges, such as a pitching wedge, a lob wedge, a gap wedge and a sand wedge. Each iron has a length that usually decreases through the set as the loft for each club head increases from the long irons to the short irons. The length of the club, along with the club head loft and center of gravity impart various performance characteristics to the ball's launch conditions upon impact. The initial trajectory of the ball extends between the impact point and the apex or peak of the trajectory. This initial portion of the ball's trajectory is of importance to golfers, because they can view it upon hitting the ball. Long irons, like the 2 iron, produce a more penetrating initial trajectory. Short irons, like the 9 iron or pitching wedge, produce an initial trajectory that is less penetrating than the trajectory of balls struck by long irons. The highest point of the long iron's ball flight is lower than the highest point for the short iron's ball flight. The mid irons, such as the 5 iron, produce an initial trajectory that is between those exhibited by balls hit with the long and short irons.
Since golfers see different initial trajectories with each iron number, golfers tend to change their swing from club-to-club in order to make the initial trajectory between clubs consistent. It would be desirable to have all the club heads in a set produce a consistent peak trajectory height along a line without requiring golfers to change their swing. This would allow golfers to use a consistent swing, which would likely improve their performance and confidence.
Therefore, it is desirable to provide a set of golf clubs that produce a substantially constant initial trajectory for the ball throughout the set.
SUMMARY OF THE INVENTION
In accordance with the present invention, a set of golf club heads is disclosed. The set includes at least first and second golf club heads. The first club head has a first loft angle and a first center of gravity. The second golf club head has a second loft angle and a second center of gravity. The first loft angle is less than the second loft angle. Each club head further includes a heel, a toe, an upper surface, a lower surface, a front face, a back face opposite the front face, and a peripheral weight defining a cavity. The first peripheral weight weighs less than the second peripheral weight so that the first center of gravity is located at a first height and the second center of gravity is located at a second height and the first height is less than the second height.
In one embodiment, the weight of the peripheral weights is varied by changing the thickness of the peripheral weights so that the thickness of the first peripheral weight is less than the thickness of the second peripheral weight. In another embodiment, the weight of the peripheral weights is varied by changing the height of the peripheral weights so that the height of an upper portion the first peripheral weight is less than the height of an upper portion the second peripheral weight.
In one embodiment, each peripheral weight has an upper thickness at the upper surface and a lower thickness spaced below the upper thickness, and the lower thickness of the first peripheral weight is less than the lower thickness of the second peripheral weight. In another such embodiment, the upper thickness is constant through the set.
Additionally or alternatively, the cavity of each head includes a cavity weight, and the cavity weight of the first club head has a weight distribution different than the cavity weight of the second club head. In other embodiments, the cavity weight further includes an upper weight and/or a lower weight. The upper weight is disposed closer to the upper surface than the lower surface. The lower weight is disposed between the upper weight and the lower surface.
In one embodiment, the set of heads further includes at least four club heads. In such an embodiment, the set further includes a 1 iron, a 2 iron, a 3 iron, a four iron, a 5 iron, a 6 iron, a 7 iron, an 8 iron, a 9 iron, and a pitching wedge.
The present invention is also directed to a set of golf clubs including first and second golf club heads and first and second shafts connected thereto respectively. The first shaft has a first shaft length and the second shaft has a second shaft length. The first length is greater than the second length.
The first club head has a first loft angle and a first center of gravity. The second golf club head has a second loft angle and a second center of gravity. The first loft angle is less than the second loft angle. Each club head further includes a heel, a toe, an upper surface, a lower surface, a front face, a back face opposite the front face, and a peripheral weight defining a cavity. In addition, the height of the first peripheral weight is less than the height of the second peripheral weight. As a result, the first center of gravity is located at a first height and the second center of gravity is located at a second height and the first height is less than the second height.
In one embodiment, each peripheral weight further includes a rear face forming a first angle with a face plane parallel to the front face, and the first angle increases along the set.
In another embodiment, each peripheral weight further includes an upper surface forming a second angle with the face plane. In one such embodiment, the second angle is constant through the set. In another such embodiment, the second angle increases from the first club to the second club.
By raising the center of gravity from the long irons to the short irons, a golfer will see a peak trajectory height along a line for each club head that is substantially more consistent along that line throughout the set than prior art clubs provide.



BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of a golf club head of the present invention;
FIG. 2 is back view of the golf club head of FIG. 1;
FIG. 3 is an enlarged, partial, cross-sectional view of the golf club head taken along line 3—3 of FIG. 2;
FIG. 4 is a toe-end view of the golf club head of FIG. 1;
FIG. 5 is a front view of a set of golf clubs of the present invention;
FIG. 6 is a set of cross-sectional views of a first embodiment of a set of golf club heads of the present invention;
FIG. 7 is a schematic, front view of a portion of the set of golf club heads of FIG. 6;
FIG. 8 is a graph showing ball flight trajectories achieved with various prior art clubs as compared to ball flight trajectories achieved with various clubs of the present invention from the set shown in FIG. 5;
FIGS. 9-17 are of cross-sectional views of various embodiments of sets of golf club heads of the present invention;
FIG. 18 is an exploded, back, perspective view of another embodiment of a golf club head of the present invention;
FIG. 19 is a back, perspective view of the golf club head of FIG. 18, wherein a plurality of weight screws are in an installed position;
FIG. 20 is a set of cross-sectional views of a set of golf club heads with configurations similar to the head of FIG. 9 and taken along line 20—20 of FIG. 19;
FIG. 21 is a set of cross-sectional views of another embodiment of a set of golf club heads of the present invention;
FIG. 22 is a cross-sectional view of a golf club head according to the present invention showing various dimensions of the club head; and
FIG. 23 is a set of cross-sectional views of another embodiment of a set of golf club heads of the present invention.



DETAILED DESCRIPTION OF THE INVENTION
Referring to FIGS. 1-3, an “iron” golf club head 10 is shown. The golf club head 10 includes a heel 12, a toe 14, a front face 16 and a back face 18 opposite the front face 16. A hosel 20 extends from the heel 12 of the head. Referring to FIG. 4, the hosel 20 in this embodiment is offset, because the front surface of the hosel is forward of the leading edge 21 of the club head. However, in another embodiment, the club head can be non-offset. Referring again to FIG. 1, the head 10 further includes an upper surface or top line edge portion 22 and a lower surface or sole 24. Both the top line 22 and the sole 24 extend from the heel 12 to the toe 14.
Referring to FIGS. 2 and 3, the back surface of the head further includes a peripheral or perimeter weight 26 that defines a cavity 28. The peripheral weight 26 has an upper portion 30 and a lower portion 32.
The cavity 28 further includes a first or upper cavity weight 34a and second or lower cavity weight 34b. The upper weight 34a extends from the upper portion 30 of the peripheral weight 26 toward the lower portion 32 of the peripheral weight 26. The lower weight 34b extends from the lower portion 32 of the peripheral weight 26 toward the upper portion 30 of the peripheral weight 26. The weights 34a and b extend from the heel 12 to the toe 14 and the lower weight 34b has a radius in the heel to toe direction. The upper and lower cavity weights 34a and b are spaced apart to form a gap 35 therebetween. Surface 36 of the upper weight 34a and surfaces 38 of the lower weight 34b are shaped so that the gap 35 has an arch-shape from the toe to the heel. The cavity weights 34a and b extend from the back face 18 of the head.
Referring again to FIG. 3, a number of dimensions of the club head will be discussed. The golf club head 10 includes a loft angle θ, which is the angle between the front face 16 and a vertical plane V perpendicular to the ground. The thickness of the top line 22 is designated by the arrow T1. The greatest thickness of the upper portion 30 of the peripheral weight is designated by the arrow T2. The thickness of the upper weight 34a is designated by the arrow T3. The thickness of the lower weight 34b is designated by the arrows T4A and B. The widest part of the lower weight 34b is designated by the arrow T4A. An intermediate thickness of the lower weight 34b is designated by the arrow T4B. In this embodiment, the lower weight 34b has dimensions so that the thickness gradually decreases between the thickness T4A and the intermediate thickness T4B. This gradual decrease allows the thicknesses T4A and B to be connected by a radius. The upper weight 34a has a back surface which is generally parallel to the front face 16. The thickness T5 of the club head across the gap 35 is the narrowest part of the club head, and extends between the front face 16 and the back face 18. Thus, thickness T5 is the strike face thickness. By adding the peripheral and cavity weights, the thickness of the peripheral weight and cavity weights are greater than the strike face thickness. The thickness measurements T1-T5 are taken generally perpendicular to the front face 16 and between the front face 16 and the back surface of the club head. The thickness of the sole 24 is designated by the arrow T6. The thicknesses T1 and T6 are taken where the radius ends on the upper and lower surfaces.
Referring to FIG. 5, the golf club head 10 is shown incorporated into a golf club 42, which is a 1 iron. The golf club 42 includes a shaft 44 and a grip 46. One end of the shaft 44 is received within the hosel 20, and the other end of the shaft 44 has the grip 46 thereon. The 1 iron has a length designated L1. Each of the remaining clubs have a length L2-LL. The long-irons are the 1 iron through the 4 iron, the mid-irons are the 5 iron through the 7 iron and the short-irons are the 8 iron through the lob wedge (LW). The short irons include a series of wedges including the pitching wedge PW, the sand wedge SW and the lob wedge LW. FIG. 5 illustrates that from the long irons to the short irons in a set of clubs 48, the length of the clubs decreases from the long irons to the short irons. The lie angle between clubs can also vary.
Referring to FIG. 6, the first embodiment of a set shown includes irons numbered from 1 to 9 and the pitching wedge. In this set, the club length decreases from the long irons to the short irons, as discussed above, so that the length progressively decreases through the set from the long irons to the short irons, as know by those of ordinary skill in the art. In this set the height of each club head increases at the toe end, the blade length increases, the lie angle substantially increases, and the sole width of the bottom surface of the sole increases from the long irons to the short irons. Furthermore, in the set 48 (as shown in FIG. 5) and the set shown in FIG. 6, the loft angle θ (as shown in FIG. 3) for each club increases through the set from the long irons to the short irons as known by those of ordinary skill in the art.
Referring to FIGS. 3 and 6, in order to have a generally consistent peak trajectory along a line throughout the set, the center of gravity of each club varies throughout the set. Referring to FIG. 7, the center of gravity for the 1 iron, 5 iron, 8 iron, and pitching wedge for the set of irons of FIG. 6 are shown as Cg1, Cg5, Cg8, and CgPW, respectively. The center of gravity is lowest in the long irons and rises generally in a vertical direction from the long irons to the short irons. The center of gravity is manipulated in order to provide a generally consistent peak trajectory along a line throughout the set, as discussed below.
Varying the center of gravity in this manner is accomplished by varying the upper and lower thicknesses of the club head. In this embodiment, the thickness T2 of the upper portion 30 and the thickness T3 of the upper weight 34a are increased from the long irons to the short irons. The thicknesses T4A and T4B of the lower weight 34b are kept substantially constant from the long irons to the short irons. The strike face thickness T5 of the head is also kept substantially constant from the long irons to the short irons. The thickness T1 of the upper surface for each club head is kept substantially constant from the long irons to the short irons. As a result, when a golfer looks down at the top line of the club head, the golfer views a substantially consistent top line thickness throughout the set. The thickness of the upper portion is varied by varying the thickness T2 of the upper portion below the upper surface. The thickness T2 is varied on an angle on the golfer's line of sight so that the upper surface thickness T1 appears the same to the golfer throughout the set. The thickness T6 of the sole 24 is substantially constant throughout the set when measured perpendicular to the front face. However, in another embodiment the sole thickness can be varied to achieve the goals of the present invention.
In the first embodiment, the club heads are cast so that the peripheral weight, cavity weight and club head are integral and formed of one material. The club heads can be cast or forged from 431 Stainless Steel or other materials including alloys well known by those of ordinary skill in the art of making clubs. The clubs can also be formed in one or more parts that are joined by various methods, for example but not limited to welded, silver soldered, brazed, or mechanically fastened with fasteners.
In another embodiment, the set of the first embodiment can be modified so that the thickness of the lower weight can be decreased from the long irons to the short irons to further move the centers of gravity in the set. In yet another embodiment, the set of the first embodiment can be modified so that the upper portion thicknesses T1 and T2 are equal to one another in a single club, but the upper portion thickness increases from the long irons to the short irons.
EXAMPLE
These and other aspects of the present invention may be more fully understood with reference to the following non-limiting example which is merely illustrative of the preferred embodiment of the present invention set of golf clubs, and is not to be construed as limiting the invention, the scope of which is defined by the appended claims.
Table I provides exemplary, non-limiting dimensions for the various measurements of the clubs shown in FIG. 6.












TABLE I





Club
T1
T2
T3
T5
Cg Vertical


Number
(inches)
(inches)
(inches)
(inches)
(inches)







1 iron
0.200
0.200
0.130
0.100
0.77


2 iron
0.200
0.208
0.138
0.100
0.78


3 iron
0.200
0.216
0.146
0.100
0.79


4 iron
0.200
0.224
0.154
0.100
0.82


5 iron
0.200
0.232
0.162
0.100
0.84


6 iron
0.200
0.240
0.170
0.100
0.86


7 iron
0.200
0.248
0.178
0.100
0.88


8 iron
0.200
0.256
0.186
0.100
0.93


9 iron
0.200
0.264
0.194
0.100
0.96


PW
0.200
0.272
0.202
0.100
0.98









As shown from Table I, the thickness T1 of the upper surface of the upper portion or top line is substantially constant from the long irons to the short irons. The thickness T2 of the upper portion increases from the long irons to the short irons by increments of 0.008 inches. The thickness T3 of the upper weight increases from the long irons to the short irons by increments of 0.008 inches. The thicknesses T4A and T5 are substantially constant. Cg Vertical is measured from the leading edge 21 (as shown in FIG. 7) to the center of gravity of the club. The overall result of increasing the upper portion and upper cavity weight thicknesses from the long irons to the short irons is to move the center of gravity from a lower position to a higher position from the long to the short irons, as evidenced by the center of gravity measurements above. Although various dimensions are described as being substantially constant throughout the set, these values may vary due to reasonable casting or forging tolerances and finishing tolerances.
Referring to FIG. 8, ball flight trajectories of prior art clubs are compared to the ball flight trajectories of clubs formed according to the present invention. FIG. 8 is a graph of Height versus Distance. The line LOS represents the line of sight of a golfer viewing each ball in flight. The ball flight trajectories labeled PAS, PAM, PAL represent the ball flight trajectories exhibited by balls hit by a set of prior art short-irons, mid-irons and long-irons, respectively. The ball flight trajectories labeled IS, IM, IL represent the ball flight trajectories exhibited by balls hit by a set of short-irons, mid-irons and long-irons, respectively, formed according to the present invention. Each prior art ball trajectory includes an apex or peak trajectory height of the flight labeled APAS, APAM, and APAL for each of the short-, mid- and long-irons. Each inventive ball trajectory includes an apex or highest point of the flight labeled AIS, AIM, and AIL for each of the short-, mid- and long-irons.
Referring to FIG. 8, the ball flight trajectory for the prior art short-irons PAS has the apex APAS which is above the golfer's line of sight LOS. The ball flight trajectory for the inventive short-irons IS has the apex AIS which is approximately at the golfer's line of sight LOS. The impact angle at which the ball hits the ground depends on whether there is a tail wind or a head wind, which consequently affects the range of impact that the ball exhibits. It is believed that the range of impact for the prior art short-irons may be about 6 yards, and the range of impact for the inventive short-irons may about 3 yards which is a decrease of about 50%. As a result of the apex of the inventive club being aligned with the golfer's line of sight, it is less susceptible to head or tail winds so that the range of impact is more narrow, thus the golfer has better control over flight distance with the new short irons. Furthermore, since the prior art apex APAS is so high when compared to the apex AIS, golfers tend to adjust their swing or choose a club with less loft to reduce the apex, particularly in windy conditions. The inventive clubs do not require the golfer to change their swing or club.
Referring to FIG. 8, the ball flight trajectory for the prior art mid-irons PAM has the apex APAM and the ball flight trajectory for the inventive mid-irons IM has the apex AIM. Both the apex APAM and AIM are approximately at the golfer's line of sight LOS. The range of impact for the prior art mid-irons and the inventive mid-irons are about the same.
Referring to FIG. 8, the ball flight trajectory for the prior art long-irons PAL has the apex APAL which is below the golfer's line of sight LOS. The ball flight trajectory for the inventive long-irons IL has the apex AIL which is approximately at the golfer's line of sight LOS. Since the initial ball flight of the prior art long irons is so penetrating, balls hit with such irons have a tendency to roll when they impact the ground. As a result, the range of impact, which includes the carry and the roll distance for the ball, for the prior art long irons depends on the topography of the golf course, which would determine where the ball would come to a stop. It is believed that the range of impact for the prior art long-irons may be about 12 yards, and the range of impact for the inventive long-irons may be about 6 yards which is a decrease of about 50%. As a result of the apex of the inventive club being aligned with the golfer's line of sight, the ball comes in more normal to the ground than a ball hit with the prior art long iron, resulting in a narrower range of impact where the ball will come to rest. The inventive balls decrease possible range of carry distances exhibited by the ball, which consequently decreases the roll distances exhibited by the ball.
Since the short-, mid-, and long-irons of the inventive set now exhibit ball flight trajectories with apexes on the golfer's line of sight, the trajectories appear more consistent along a line throughout the set to the golfer. Thus, by varying the center of gravity of each club head from the long irons to the short irons according to the present invention, the peak trajectory height along a line appears substantially consistent from club-to-club in the set.
Referring to FIG. 9, a second embodiment of a set of golf clubs of the present invention is represented by a 1 iron, 6 iron and pitching wedge (PW) shown. The maximum thickness T4A of the lower weight 34b decreases from the long irons to the short irons, consequently the total thickness of the lower weight 34b decreases from the long irons to the short irons. The thickness T3 of the upper weight 34a increases from the long irons to the short irons. Thus, the thickness of the lower weight 34b and upper weight 34a are inversely proportional from the long irons to the short irons. The thickness T1, T2 of the upper portion 30 increases from the long irons to the short irons. The thicknesses T1 and T2 are equal for each club. As a result of varying the thicknesses of the cavity weights and upper portion, the center of gravity rises from the long irons to the short irons so that the peak trajectory height along a line throughout the set appears generally consistent. The center of gravity Cg of the 6 iron defines a reference line R, and the center of gravity Cg of the 1 iron is below the line R, while the center of gravity Cg of the pitching wedge is above the line R. When the 1 iron, 6 iron and PW of the set of FIG. 9 are incorporated into a set of irons shown in FIG. 5, the center of gravity rises from the long irons to the short irons.
Referring to FIG. 10, a third embodiment of a set of golf clubs of the present invention is represented by a 1 iron, 6 iron and pitching wedge (PW) illustrated. The maximum thickness T4A of the lower weight 34b decreases from the long irons to the short irons, consequently the total thickness of the lower weight 34b decreases from the long irons to the short irons. The thickness T3 of the upper weight 34a is constant from the long irons to the short irons. The thickness of the upper portion T1,T2 increases from the long irons to the short irons. The thicknesses T1 and T2 are equal for each club. As a result of varying the thicknesses of the lower weight and upper portion, the center of gravity rises from the long irons to the short irons so that the peak trajectory height along a line throughout the set appears generally consistent. The center of gravity Cg of the 6 iron defines a reference line R, and the center of gravity Cg of the 1 iron is below the line R, while the center of gravity Cg of the pitching wedge is above the line R. When the 1 iron, 6 iron and PW of the set of FIG. 10 are incorporated into a set of irons shown in FIG. 5, the center of gravity rises from the long irons to the short irons.
Referring to FIG. 11, a fourth embodiment of a set of golf clubs of the present invention is represented by a 1 iron, 6 iron and pitching wedge (PW) illustrated. The maximum thickness T4A of the lower weight 34b is constant from the long irons to the short irons. The thickness T3 of the upper weight 34a increases from the long irons to the short irons. The thickness T1, T2 of the upper portion increases from the long irons to the short irons. The thicknesses T1 and T2 are equal for each club. The thickness T6 of the sole decreases from the long irons to the short irons. As a result of varying the thickness of the upper weight, the upper portion, and the sole, the center of gravity rises from the long irons to the short irons so that the peak trajectory height along a line throughout the set appears generally consistent. The center of gravity Cg of the 6 iron defines a reference line R, and the center of gravity Cg of the 1 iron is below the line R, while the center of gravity Cg of the pitching wedge is above the line R. When the 1 iron, 6 iron and PW of the set of FIG. 11 are incorporated into a set of irons shown in FIG. 5, the center of gravity rises from the long irons to the short irons.
In another embodiment, the set of the fourth embodiment can be modified so that the thickness of lower weight decreases from the long irons to the short irons. In yet another embodiment, the set of the fourth embodiment can be modified so that the thickness of the upper weight is held constant from the long irons to the short irons.
Referring to FIG. 12, a fifth embodiment of a set of golf clubs of the present invention is represented by a 1 iron, 6 iron and pitching wedge (PW) illustrated. The maximum thickness T4A of the lower weight 34b decreases from the long irons to the short irons, consequently the total thickness of the lower weight 34b decreases from the long irons to the short irons. The thickness T3 of the upper weight 34a is constant from the long irons to the short irons. The thicknesses T1, T2 of the upper portion 30 increase from the long irons to the short irons, and the thicknesses T1 and T2 are equal for each club. The thickness T6 of the sole decreases from the long irons to the short irons. As a result of varying the thicknesses of the lower weight, the upper portion, and the sole, the center of gravity rises from the long irons to the short irons so that the peak trajectory height along a line throughout the set appears generally consistent. The center of gravity Cg of the 6 iron defines a reference line R, and the center of gravity Cg of the 1 iron is below the line R, while the center of gravity Cg of the pitching wedge is above the line R. When the 1 iron, 6 iron and PW of the set of FIG. 12 are incorporated into a set of irons shown in FIG. 5, the center of gravity rises from the long irons to the short irons.
In another embodiment, the set of the fifth embodiment can be modified so that the thickness of upper weight increases from the long irons to the short irons.
Referring to FIG. 13, a sixth embodiment of a set of golf clubs of the present invention is represented by a 1 iron, 6 iron and pitching wedge (PW) illustrated. The maximum thickness T4A of the lower weight 34b decreases from the long irons to the short irons, consequently decreases from the long irons to the short irons. The thickness T3 of the upper weight 34a is constant from the long irons to the short irons. The thicknesses T1, T2 of the upper portion is constant from the long irons to the short irons. The thicknesses T1 and T2 are equal for each club. As a result of varying the thickness of the lower weight, the center of gravity rises from the long irons to the short irons so that the peak trajectory height along a line throughout the set appears generally consistent. The center of gravity Cg of the 6 iron defines a reference line R, and the center of gravity Cg of the 1 iron is below the line R, while the center of gravity Cg of the pitching wedge is above the line R. When the 1 iron, 6 iron and PW of the set of FIG. 13 are incorporated into a set of irons shown in FIG. 5, the center of gravity rises from the long irons to the short irons.
In another embodiment, the set of the sixth embodiment can be modified so that the thicknesses of the sole and/or lower peripheral weight decrease from the long irons to the short irons. In yet another embodiment, the set of the sixth embodiment can be modified so that the thickness of the lower weight is constant and the thickness of the upper weight increases from the long irons to the short irons.
Referring to FIG. 14, a seventh embodiment of a set of golf clubs of the present invention is represented by a 1 iron, 6 iron and pitching wedge (PW) illustrated. The maximum thickness T4A of the lower weight 34b decreases from the long irons to the short irons, consequently the total thickness of the lower weight 34b decreases from the long irons to the short irons. The thickness T3 of the upper weight 34a increases from the long irons to the short irons. The thicknesses T1, T2 of the upper portion 30 is constant from the long irons to the short irons. As a result of varying the thickness of the lower and upper weights, the center of gravity rises from the long irons to the short irons so that the peak trajectory height along a line throughout the set appears generally consistent. The center of gravity Cg of the 6 iron defines a reference line R, and the center of gravity Cg of the 1 iron is below the line R, while the center of gravity Cg of the pitching wedge is above the line R. When the 1 iron, 6 iron and PW of the set of FIG. 14 are incorporated into a set of irons shown in FIG. 5, the center of gravity rises from the long irons to the short irons.
In another embodiment, the set of the seventh embodiment can be modified so that the thicknesses of the sole and/or lower peripheral weight decrease from the long irons to the short irons.
Referring to FIG. 15, a eighth embodiment of a set of golf clubs of the present invention is represented by a 1 iron, 6 iron and pitching wedge (PW) illustrated. The maximum thickness T4A of the lower weight decreases from the long irons to the short irons, consequently the total thickness of the lower weight 34b decreases from the long irons to the short irons. The thickness T3 of the upper weight 34a is constant from the long irons to the short irons. The thicknesses T1, T2 of the upper portion 30 is constant from the long irons to the short irons. The majority of the club head is formed of a first material M1 and a small amount of a second material M2 replaces the first material M1 that forms the upper portion of the 6 iron and the pitching wedge (PW). The first material M1 is less dense than the second material M2. The amount of second material M2 increases from the long irons to the short irons. As a result of varying the thickness of the lower weight, and increasing the amount of a more dense second material on the upper portion from the long irons to the short irons, the center of gravity is lowest in the long irons and rises from the long irons to the short irons so that the peak trajectory height along a line throughout the set appears generally consistent. The center of gravity Cg of the 6 iron defines a reference line R, and the center of gravity Cg of the 1 iron is below the line R, while the center of gravity Cg of the pitching wedge is above the line R. When the 1 iron, 6 iron and PW of the set of FIG. 15 are incorporated into a set of irons shown in FIG. 5, the center of gravity rises from the long irons to the short irons.
Recommended first materials M1 include, but are not limited to titanium, aluminum, stainless steel or metal alloys, or composite materials. Composite materials can include various resins combined with matrix material, for example thermoplastic or thermosetting resins or the like combined with a fiber glass, graphite, ceramic matrix or the like. Recommended second materials M2 include, but are not limited to tungsten, copper, brass, or alloys thereof. The second material can be applied by flame spraying onto the club head formed of the first material.
In another embodiment, the set of the eighth embodiment can be modified so that the thicknesses of the sole and/or lower peripheral weight decrease from the long irons to the short irons, and/or the thicknesses of the upper weight and upper portion vary from the long irons to the short irons. In yet another embodiment, the set of the eighth embodiment can be modified so that the thickness of the lower weight is constant from the long irons to the short irons. In another embodiment, the set of the eighth embodiment can be modified so that the upper weight has the second material thereon, and the amount of the second material increases from the long irons to the short irons. The second material on the upper weight can be used in combination with the second material on the upper portion of the peripheral weight or without the second material on the upper portion.
Referring to FIG. 16, a ninth embodiment of a set of golf clubs of the present invention is represented by a 1 iron, 6 iron and pitching wedge (PW) illustrated. The maximum thickness T4A of the lower weight 34b is constant from the long irons to the short irons. The thickness T3 of the upper weight 34a increases from the long irons to the short irons. The thicknesses T1, T2 of the upper portion 30 increases from the long irons to the short irons. The thicknesses T1 and T2 for each club head are equal. The majority of the club head is formed of a first material M1 and a small amount of a second material M2 replaces the first material that forms the lower weight. Therefore, the second material does not change the height of the iron. The first material M1 is less dense than the second material M2. The amount of second material M2 decreases from the long irons to the short irons. As a result of varying the thickness of the upper weight and upper portion, and adding a decreasing amount of a more dense second material to the lower weight from the long irons to the short irons, the center of gravity rises from the long irons to the short irons so that the peak trajectory height along a line throughout the set appears generally consistent. The center of gravity Cg of the 6 iron defines a reference line R, and the center of gravity Cg of the 1 iron is below the line R, while the center of gravity Cg of the pitching wedge is above the line R. When the 1 iron, 6 iron and PW of the set of FIG. 16 are incorporated into a set of irons shown in FIG. 5, the center of gravity rises from the long irons to the short irons.
In another embodiment, the set of the ninth embodiment can be modified so that the thicknesses of the sole and/or lower peripheral weight decrease from the long irons to the short irons, and/or the thicknesses of the upper weight and/or upper portion are constant from the long irons to the short irons. In yet another embodiment, the set of the ninth embodiment can be modified so that the thickness of the lower weight decreases from the long irons to the short irons.
Referring to FIG. 17, a tenth embodiment of a set of golf clubs of the present invention is represented by a 1 iron, 6 iron and pitching wedge (PW) illustrated. The maximum thickness T4A of the lower weight 34b is constant from the long irons to the short irons. The thickness T3 of the upper weight 34a increases from the long irons to the short irons. The thicknesses T1, T2 of the upper portion 30 increase from the long irons to the short irons. The thicknesses T1 and T2 in this embodiment are equal. The majority of the club head is formed of a first material M1 and a small amount of a second material M2 is added to the sole. The first material M1 is less dense than the second material M2. The amount of second material M2 decreases from the long irons to the short irons. As a result of varying the thickness of the upper weight and upper portion, and adding a decreasing amount of a more dense second material to the sole from the long irons to the short irons, the center of gravity rises from the long irons to the short irons so that the peak trajectory height along a line throughout the set appears generally consistent. The center of gravity Cg of the 6 iron defines a reference line R, and the center of gravity Cg of the 1 iron is below the line R, while the center of gravity Cg of the pitching wedge is above the line R. When the 1 iron, 6 iron and PW of the set of FIG. 17 are incorporated into a set of irons shown in FIG. 5, the center of gravity rises from the long irons to the short irons.
In another embodiment, the set of the tenth embodiment can be modified so that the thicknesses of the sole and/or lower peripheral portion decrease from the long irons to the short irons, and/or the thicknesses of the upper weight and/or upper portion are constant from the long irons to the short irons. In yet another embodiment, the set of the tenth embodiment can be modified so that the thickness of the lower weight decreases from the long irons to the short irons.
Referring to FIGS. 18 and 19, another embodiment of a golf club head 10′ is shown. The golf club head 10′ is similar to the golf club head 10 discussed with respect to FIGS. 1-4; however, the golf club head 10′ has been modified to include two internally, threaded bores 60 and 62 in the lower weight 34b. The threaded bore 60 is adjacent the heel 12 and the bore 62 is adjacent the toe 14. The threaded bores 60 and 62 receive externally, threaded weight screws 64 and 66, respectively. These screws can be glued for more securement. The majority of the club head is formed of a first material M1 and the threaded screws are formed of a second material M2. The first material M1 is less dense than the second material M2. The first and second materials can include those described with respect to the embodiments shown in FIGS. 15-17.
Referring to FIGS. 18 and 20, the golf club head 10′ is incorporated into an eleventh embodiment of a set of golf clubs of the present invention. The eleventh set of golf clubs of the present invention is represented by a 1 iron, 6 iron and pitching wedge (PW) illustrated. The maximum thickness T4A of the lower weight 34b is constant. The thickness T3 of the upper weight 34a increases from the long irons to the short irons. The thicknesses T1, T2 of the upper portion 30 increase from the long irons to the short irons. The thicknesses T1 and T2 in this embodiment are equal for each club. The majority of the club head is formed of the first material M1 and the weight screws 64 and 66 are formed of the second material M2 and added to the lower weight. The position of the screws rises from long irons to the short irons. As a result of varying the thickness of the upper weight and upper portion, and moving the weight screws upward from the long irons to the short irons, the center of gravity rises from the long irons to the short irons so that the peak trajectory height along a line throughout the set appears generally consistent. The center of gravity Cg of the 6 iron defines a reference line R, and the center of gravity Cg of the 1 iron is below the line R, while the center of gravity Cg of the pitching wedge is above the line R. When the 1 iron, 6 iron and PW of the set of FIG. 20 are incorporated into a set of irons shown in FIG. 5, the center of gravity rises from the long irons to the short irons.
In another embodiment, the set of the eleventh embodiment can be modified so that the weight screws are located in the upper weight. In another embodiment, the set of the eleventh embodiment can be modified so that the thicknesses of the sole and/or lower peripheral weight decrease from the long irons to the short irons, and/or the thicknesses of the upper weight and/or upper portion are constant from the long irons to the short irons. In yet another embodiment, the set of the eleventh embodiment can be modified so that the thickness of the lower weight decreases from the long irons to the short irons.
Referring to FIG. 21, a twelfth embodiment of a set of golf clubs of the present invention is represented by a 1 iron, 6 iron and pitching wedge (PW) illustrated. The maximum thickness T4A of the lower weight 34b decreases from the long irons to the short irons, consequently the total thickness of the lower weight 34b decreases from the long irons to the short irons. The thickness T3 of the upper weight 34a increases from the long irons to the short irons. The thicknesses T1, T2 of the upper portion 30 are constant from the long irons to the short irons. Furthermore, the 1 iron and the pitching wedge are substantially formed of a first material M1, and further include a second material M2 that is heavier than the first material, and a third material M3 that is lighter than the first material. On the 1 iron, the first material M1 is removed and replaced with the heavier material M3 located in the sole 24 and the second lighter material M2 located in the upper portion 30. On the pitching wedge, the first material M1 is removed and replaced with the heavier material M3 located in the upper portion 30 and the second lighter material M2 located in the sole 24. The 6 iron is formed of the first material. As a result of varying the thickness of the lower and upper weights and locating heavier and lighter materials in various places on each club, the center of gravity rises from the long irons to the short irons so that the peak trajectory height along a line throughout the set appears generally consistent. The center of gravity Cg of the 6 iron defines a reference line R, and the center of gravity Cg of the 1 iron is below the line R, while the center of gravity Cg of the pitching wedge is above the line R. When the 1 iron, 6 iron and PW of the set of FIG. 21 are incorporated into a set of irons shown in FIG. 5, the center of gravity rises from the long irons to the short irons. By using a heavier and a lighter material it is easier to remove the first material as necessary and still allow each club head to weigh the necessary amount.
Referring to FIGS. 22 and 23, another embodiment of a golf club head 110 is shown. The golf club head 110 is similar to the golf club head 10 discussed with respect to FIGS. 1-4. Thus, it includes a face 116, a back face 118, an upper surface or top line 122, a sole 124, a peripheral weight 126, an upper portion 130 of the peripheral weight, a lower portion 132 of the peripheral weight, an upper cavity weight 134a, a lower cavity weight 134b, and a gap 135 therebetween.
The thickness of the top line 122 or upper surface of the upper peripheral weight portion is designated by the arrow T1. The greatest thickness of the upper portion 130 of the peripheral weight is designated by the arrow T2. The thickness of the upper weight 134a is designated by the arrow T3. The thickness of the lower weight 34b is designated by the arrows T4A and B. The widest part of the lower weight 134b is designated by the arrow T4A. An intermediate thickness of the lower weight 134b is designated by the arrow T4B. In this embodiment, the lower weight 134b has dimensions so that the thickness gradually decreases between the thickness T4A and the intermediate thickness T4B. This gradual decrease allows the thicknesses T4A and B to be connected by a radius. The upper weight 134a has a back surface which is generally parallel to the front face 116. The thickness T5 of the club head across the gap 135 is the narrowest part of the club head, and extends between the front face 116 and the back face 118. The sole 124 has a thickness T6. The thicknesses T1-T6 are measured as discussed above with respect to FIG. 3.
The club head 110 further includes a vertical plane V1 parallel to a plane F defined by the front face 116. The upper portion 130 of the peripheral weight further includes a rear face 130a. The rear face 103a defines a plane R. An angle α is defined between the plane P and the plane R. A top line angle β is defined between the top line 122 and the plane F. The upper portion 130 of the club head 110 further includes a height H.
Referring to FIG. 23, the golf club head 110 is shown incorporated into a set of irons including irons numbered from 1 to 9 and the pitching wedge. In this set, the club shaft length decreases from the long irons to the short irons, as discussed above with respect to FIG. 5, so that the length progressively decreases through the set from the long irons to the short irons, as know by those of ordinary skill in the art. In this set, the loft angle for each club increases through the set from the long irons to the short irons as known by those of ordinary skill in the art.
In the set shown in FIG. 23, the maximum thickness T4A of the lower weight 134b is constant from the long irons to the short irons. The thickness T3 of the upper weight 134a increases from the long irons to the short irons. The thickness T1 of the upper surface or top line 122 is constant throughout the set. The maximum thickness T2 of the upper portion 130 of the peripheral weight increases from the long irons to the short irons. As a result of the dimensions of the thicknesses T1 and T2, the angle α increases from the long irons to the short irons. The height H of the upper portion 130 increases from the long irons to the short irons. The thickness T6 of the sole is constant from the long irons to the short irons. As a result of varying the thickness of the upper weight, the maximum thickness of the upper portion, and the height of the upper portion, the center of gravity rises from the long irons to the short irons so that the peak trajectory height along a line throughout the set appears generally consistent.
In another embodiment, the set of FIG. 23 can be modified so that only the maximum thickness or the height of the upper portion varies alone or in combination with varying the thickness of the upper weight. In yet another embodiment, the set of the thirteenth embodiment can be modified so that the thicknesses of the lower weight and/or sole thicknesses decrease from the long irons to the short irons. In yet another embodiment, the set of the thirteenth embodiment can be modified so that the thickness of the upper weight is held constant from the long irons to the short irons. Alternatively, the thicknesses T1 and T2 can be the same for each club in the set, but the thickness of the upper portion increases throughout the set.
EXAMPLE
These and other aspects of the present invention may be more fully understood with reference to the following non-limiting example which is merely illustrative of the preferred embodiment of the present invention set of golf clubs, and is not to be construed as limiting the invention, the scope of which is defined by the appended claims.
Table II provides exemplary, non-limiting dimensions for the various measurements of the clubs shown in FIG. 23.













TABLE II





Club
T1
T2
T3
H
α
Cg Vertical


Number
(inches)
(inches)
(inches)
(inches)
(degrees)
(inches)





















1 iron
0.198
0.222
0.047
0.218
6.0
0.77


2 iron
0.198
0.229
0.054
0.223
7.5
0.78


3 iron
0.198
0.236
0.061
0.228
9.0
0.79


4 iron
0.198
0.243
0.068
0.233
10.4
0.82


5 iron
0.198
0.250
0.075
0.238
11.7
0.84


6 iron
0.198
0.257
0.082
0.243
13.0
0.87


7 iron
0.198
0.264
0.089
0.248
14.2
0.89


8 iron
0.198
0.271
0.096
0.253
15.4
0.93


9 iron
0.198
0.278
0.103
0.258
16.5
0.95


PW
0.198
0.285
0.110
0.263
17.6
0.97









As shown from Table II, the thickness T1 of the upper surface of the upper portion or top line is substantially constant from the long irons to the short irons. The thickness T2 of the upper portion increases from the long irons to the short irons by increments of 0.007 inches. The thickness T3 of the upper cavity weight increases from the long irons to the short irons by increments of 0.007 inches. The thicknesses T4A, T5 and T6 (as shown in FIG. 22) are substantially constant. The height H of the upper portion of the peripheral weight increases from the long irons to the short irons by increments of 0.005 inches.
The angle α between the rear face 130a and the vertical plane V1 (as shown in FIG. 22) increases from the long irons to the short irons. The angle α varies in increments of 1.5 degrees between the 1 iron and the 2 iron and between the 2 iron and the 3 iron. The angle α varies in increments of 1.4 degrees between the 3 iron and the 4 iron. The angle α varies in increments of 1.3 degrees between the 4 iron and the 5 iron and between the 5 iron and the 6 iron. The angle α varies in increments of 1.2 degrees between the 6 iron and the 7 iron and between the 7 iron and the 8 iron. The angle α varies in increments of 1.1 degrees between the 8 iron and the 9 iron and between the 9 iron and the pitching wedge.
In addition, the top line angle β is constant at 98° throughout the set. However, in another embodiment the top line angle β can vary. For example, the top line angle β can change from 5° in the 1 iron to 15° in the pitching wedge where the change is progressive along the set.
Cg Vertical is measured from the leading edge 21 (as shown in FIG. 7) to the center of gravity of the club. The overall result of increasing the thickness and height of the upper portion and the thickness of the upper cavity weight from the long irons to the short irons is to move the center of gravity from a lower position to a higher position from the long to the short irons, as evidenced by the center of gravity measurements above. Although various dimensions are described as being substantially constant throughout the set these values may vary due to reasonable casting or forging tolerances and finishing tolerances.
While it is apparent that the illustrative embodiments of the invention disclosed herein fulfill the objectives stated above, it is appreciated that numerous modifications and other embodiments may be devised by those skilled in the art. The sets of clubs disclosed can include a series of wedges, each with a different loft, such as pitching, lob, gap and sand wedges. The features disclosed to vary the center of gravity, as discussed above, can be used in different combinations so that the objective of raising the center of gravity from the long irons to the short irons is achieved. The thickness of the upper portion can be varied by varying the top line thickness alone, by varying the lower upper portion thickness alone, or by varying both. Instead of varying the thickness of the lower weight by varying the entire thickness of the cavity weight, just a portion of the thickness of the cavity weights can be varied. On the other hand, the upper weight can be varied by varying the entire thickness of the weight or by varying just a portion of the thickness. Where a first material and a second more dense material are used, these materials can also be joined by brazing, bonding by for example epoxy or mechanical fasteners, such as pins.
Another modification, can be changing the center of gravity from the long irons to the short irons in subsets. Thus, for example a first group of long irons have first center of gravity, a second group of mid irons have a second center of gravity, and a group of short irons have a third center of gravity. The vertical position of the center of gravity is about the same within a group, however, the first center of gravity is the lowest and the second and third centers of gravity increase from the first group to the third group. Therefore, it will be understood that the appended claims are intended to cover all such modifications and embodiments which would come within the spirit and scope of the present invention.

## Claims

1. A set of golf club heads comprising:
a first golf club head comprising a heel, a toe, an upper surface, a lower surface, a front face, and a back face opposite the front face, wherein the first golf club head has a first peripheral weight defining a first cavity, wherein the first peripheral weight has a first thickness corresponding to the upper surface and a second thickness corresponding to the lower surface, and wherein the first cavity comprises an upper cavity weight extending from the upper surface of the first peripheral weight towards the lower surface of the first peripheral weight and a lower cavity weight extending from the lower surface of the first peripheral weight towards the upper surface of the first peripheral weight; and 
a second golf club head comprising a heel, a toe, an upper surface, a lower surface, a front face, and a back face opposite the front face, wherein the second golf club head has a second peripheral weight defining a second cavity, wherein the second peripheral weight has a third thickness corresponding to the upper surface and a fourth thickness corresponding to the lower surface, wherein the third thickness is greater than the first thickness, and wherein the second cavity comprises an upper cavity weight extending from the upper surface of the second peripheral weight towards the lower surface of the second peripheral weight and a lower cavity weight extending from the lower surface of the second peripheral weight towards the upper surface of the second peripheral weight, and wherein the upper and lower cavity weights of the first and second cavities have an arch shape gap therebetween.

2. The set of golf club heads of claim 1, wherein the fourth thickness is less than the second thickness.

3. The set of golf club heads of claim 1, wherein the second thickness and fourth thickness are substantially constant.

4. The set of golf club heads of claim 1, wherein the upper and lower cavity weights of the first golf club head extend from the heel to the toe.

5. The set of golf club heads of claim 1, wherein the second cavity further upper and lower cavity weights of the second golf club head extend from the heel to the toe.

6. The set of golf club heads of claim 1, further comprising at least four club heads.

7. A set of golf club heads comprising:
a first golf club head comprising a heel, a toe, an upper surface, a lower surface, a front face, and a back face opposite the front face, wherein the first golf club head has a first peripheral weight defining a first cavity, wherein the first cavity comprises a first cavity weight comprising a first upper cavity weight proximate the upper surface and a first lower cavity weight proximate the lower surface, and wherein the first upper cavity weight and first lower cavity weight have an arch shape gap therebetween; and 
a second golf club head comprising a heel, a toe, an upper surface, a lower surface, a front face, and a back face opposite the front face, wherein the second golf club head has a second peripheral weight defining a second cavity, wherein the second cavity comprises a second cavity weight comprising a second upper cavity weight proximate the upper surface and a second lower cavity weight proximate the lower surface, and wherein the second upper cavity weight and second lower cavity weight have an arch shape gap therebetween, and 
wherein the first cavity weight has a different weight distribution than the second cavity weight.

8. The set of golf club heads of claim 7, wherein the first lower cavity weight has a first thickness and the second lower cavity weight has a second thickness less than the first thickness.

9. The set of golf club heads of claim 8, wherein the first upper cavity weight has a third thickness and the second upper cavity weight has a fourth thickness greater than the third thickness.

10. The set of golf club heads of claim 7, wherein the first lower cavity weight has a first thickness and the second lower cavity weight has a second thickness, and wherein the first thickness and the second thickness are substantially constant.

11. The set of golf club heads of claim 7, wherein the first upper cavity weight weighs less than the second cavity upper weight.

12. A set of golf clubs comprising:
a plurality of golf clubs, wherein each club comprises: 
a shaft; and 
a club head, wherein each club head comprises a heel, a toe, an upper surface, a lower surface, a front face, a back face opposite the front face, and a peripheral weight defining a cavity, wherein the peripheral weight comprises an upper portion proximate the upper surface and a lower portion proximate the lower surface, wherein the cavity comprises an upper cavity weight extending from the upper surface towards the lower surface and a lower cavity weight extending from the lower surface towards the upper surface, and wherein the upper and lower cavity weights have an arch shape gap therebetween, and 

wherein the plurality of clubs are designed so that as the club number ascends, the upper portion increases in thickness.

13. The set of clubs of claim 12, wherein the thickness of the lower portions are constant throughout the set.

14. The set of clubs of claim 12, wherein the upper cavity weight has a maximum thickness, and wherein the maximum thickness is constant as the club number ascends.

15. The set of clubs of claim 12, wherein the lower cavity weight has a maximum thickness, and wherein the maximum thickness decreases as the club number ascends.

16. The set of clubs of claim 12, wherein the plurality of clubs are designed so that as the club number ascends, the thickness of the upper weight increases.