TECHNICAL FIELD OF THE INVENTIONThe present invention generally relates to sets of iron golf clubs, and more particularly, to sets of iron golf clubs that are comprised of significant tungsten weighting.
BACKGROUND OF THE INVENTIONIn 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.” In general, the greater the loft is of the golf club in a set, the greater the launch angle and the less distance the golf ball is hit.
A set of irons generally includes individual irons that are designated as number 3 through number 9, and a pitching wedge. The iron set is generally complimented by a series of wedges, such as a lob wedge, a gap wedge, and/or a sand wedge. Sets can also include a 1 iron and a 2 iron, but these clubs are generally sold separate from the set. Each iron has a shaft 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 generally extends between the impact point and the apex or peak of the trajectory. In general, the ball's trajectory for long irons, like the 3 iron, is a more penetrating, lower trajectory due to the lower launch angle and the increased ball speed off of the club. Short irons, like the 8 iron or pitching wedge, produce a trajectory that is substantially steeper and less penetrating than the trajectory of balls struck by long irons. The highest point of the long iron's ball flight is generally 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.
SUMMARY OF THE INVENTIONThe present invention is directed to a set of golf clubs comprising at least a first club head having a loft between about 15 and 25 degrees (long irons), a second club head having a loft of between about 26 and 35 degrees (mid irons), and a third club head having a loft of about 36 degrees or greater (short irons). Within the set, the first, second and third club heads each have a heel, a toe, a topline, a sole, a hosel and a front face having a face center. Each of the club heads has a club head mass that is different than the other club head mass by at least 5 grams. Further, the set includes at least one club head that has a tungsten heel member and a tungsten toe member that together comprise more that 50% of the club head mass. More preferably, each of the long irons and the mid irons are comprised of tungsten weight members that are at least 50% of the club head mass.
The present invention is also directed to a set of irons where the long and mid irons each have a tungsten heel member and a tungsten toe member, wherein the tungsten heel member plus the tungsten toe member weigh 135 grams or greater. Preferably, the long and mid irons are comprised of titanium and tungsten and the tungsten portion forms more than 25% of the club heads' volume. In a preferred embodiment, the short iron is comprised of titanium and steel and the steel portion comprises between 50% and 70% of the club head mass.
The present invention is also directed to a set of golf clubs comprising at least a first club head having a loft between about 15 and 25 degrees, a second club head having a loft of between about 26 and 35 degrees, and a third club head having a loft of about 36 degrees or greater, where each club head has a club head mass that is different than the one preceding it by at least 5 grams and at least one club head is comprised of a steel body member and a steel face insert that together comprise less than 75 percent of the overall club head mass. Preferably, the club head includes a tungsten heel member and a tungsten toe member that together comprise more that 25% of the club head mass. More preferably, the tungsten heel member plus the tungsten toe member weigh 70 grams or greater.
In a preferred embodiment of the invention, the long irons and mid irons are comprised of steel and tungsten and the tungsten portion forms at least about 20 percent of the club heads' solid volume. Still further, at least one short iron can be comprised of steel and tungsten and the tungsten portion comprises at least about 20 percent of the club head mass.
The present invention also contemplates a set of golf clubs comprising at least a long iron having a first blade length, a first hosel length and a first scoreline width, a mid iron having a second blade length, a second hosel length and a second scoreline width, and a short iron having a third blade length, a third hosel length and a third scoreline width, where the blade lengths are approximately constant and the second hosel length is greater than the first hosel length and the third hosel length is greater than the second hosel length. Also the second scoreline width is preferably less than the first scoreline width and the third scoreline width is preferably less than the second scoreline width. In a preferred embodiment, long iron has a first toe height, the mid iron has a second toe height greater than the first toe height and the short iron has a third toe height greater than the second toe height. Still further, the long iron can have a first sole width, the mid iron can have a second sole width less than the first sole width and the short iron can have a third sole width less than the second sole width.
In the preferred embodiment of the current invention, the long iron has a first tungsten toe member, the mid iron has a second tungsten toe member with greater mass than the first tungsten toe member and at least one short iron has a third tungsten toe member with greater mass than the second tungsten toe member. Conversely, in the preferred embodiment, the long iron has a first tungsten heel member and the mid iron has a second tungsten heel member with less mass than the first tungsten heel member.
BRIEF DESCRIPTION OF THE DRAWINGSFIG. 1 is a back view of an iron according to the present invention;
FIG. 2 is a perspective view of the iron inFIG. 1;
FIG. 3 is a front view of a long iron according to another embodiment of the present invention;
FIG. 4 is a front view of a long iron body member according to the present invention;
FIG. 5 is a front view of a mid-iron body member according to the present invention;
FIG. 6 is a front view of a short iron body member according to the present invention; and;
FIG. 7 is a front view of another embodiment of a short iron body member according to the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTSAs illustrated in the accompanying drawings and discussed in detail below, the present invention is directed to an improved set of iron-type golf clubs, wherein the clubs have tungsten weight members that form a significant portion of the club heads' mass.
Referring toFIGS. 1 and 2, aniron10 has aheel12, atoe14, ahosel16, a back cavity18 atop line20 and a sole22. The iron is comprised of two main components, themain body24 and theweight members26. The iron includes ahosel axis34 and a face center FC. Themain body24 is formed from titanium, or more preferably, a titanium alloy. For at least the long irons and mid irons, the weight members include atoe weight member28 and aheel weight member30 that are formed from tungsten or more preferably a tungsten alloy having a specific gravity of 15 g/cm3 or greater. Thus, themain body24 will have a specific gravity of about 4-5 g/cm3 and theweight members26 will have a specific gravity of about 15-20 g/cm3.
Table I provides exemplary, non-limiting dimensions for the various measurements of clubs according to the Example of the invention. It is fully intended that all of the dimensions set forth below can be adjusted such that the overall objective of the individual irons is met.
| TABLE I |
|
| Club Number | 3 | 4 | 5 | 6 | 7 | 8 | 9 | P |
|
|
| loft | 21 | 24 | 27 | 30 | 34 | 38 | 42 | 46 |
| Mass | 238 | 245 | 252 | 259 | 266 | 274 | 282 | 286 |
| Ti (g) | 103 | 100 | 102 | 109 | 116 | 94 | 102 | 106 |
| W (g) | 135 | 145 | 150 | 150 | 150 |
| Steel (g) | | | | | | 180 | 180 | 180 |
| Ti % | 43.3 | 40.8 | 40.5 | 42.1 | 43.6 | 34.3 | 36.2 | 37.1 |
| W % | 56.7 | 59.2 | 59.5 | 57.9 | 56.4 |
| Steel % | | | | | | 65.7 | 63.8 | 62.9 |
| Ti vol. (cm3) | 22.9 | 22.2 | 22.7 | 24.2 | 25.8 | 20.9 | 22.7 | 23.6 |
| W vol. (cm3) | 9.0 | 9.7 | 10 | 10 | 10 |
| Steel Vol. | | | | | | 24 | 24 | 24 |
| (cm3) |
|
Referring to the data in Table I above, the set of irons according to the present invention can be separated into long irons that have a loft of between about 15 and 25 degrees, mid irons that have a loft of between about 26 and 35 degrees and short irons that have a loft of about 36 or greater. The total mass of the clubs increases throughout the set from about 235 grams to about 290 grams. Each club is preferably about 5 grams or more greater in mass than the previous iron. As shown, for example, the 4 iron is 7 grams greater than the 3 iron. Thus, the mass increases through the set.
Each of the irons includes a titanium body member. The long irons and the mid irons preferably havetungsten weight members28 and30 as shown inFIGS. 1 and 2. In the long irons, thetitanium body member24 has a mass that is less than about 120 grams and more particularly, about 100 grams. Thetoe weight member28 andheel weight member30 preferably have a mass of about 130 grams to 150 grams. Thus, the tungsten weight members are greater than 50% of the total club mass.
In the mid irons, thetitanium body member24 has a mass that is less than about 120 grams and more particularly, about 100 grams to about 115 grams. The tungstentoe weight member28 andheel weight member30 preferably have a mass of about 140 grams to 160 grams, and more particularly about 150 grams. Thus, the tungsten weight members are greater than 50% of the total club mass. Also, thetungsten weight members28 and30 have greater mass than thetungsten weight members28 and30 for the long irons.
In the short irons, thetitanium body member24 has a mass that is less than about 120 grams and more particularly, about 90 grams to about 110 grams. Thetoe weight member28 andheel weight member30 are preferably made of steel and preferably have a mass of about 160 grams to 200 grams, and more particularly about 180 grams. Thus, the steel weight members are greater than 50% of the total club mass. Also, thesteel weight members28 and30 have greater mass than thetungsten weight members28 and30 for the long irons and of the mid irons.
| TABLE II |
|
| Club Number | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | P |
|
|
| loft | 17 | 20 | 23 | 26 | 29 | 33 | 37 | 41 | 45 |
| Total Mass (g) | 234 | 239 | 246 | 252 | 256 | 267 | 274 | 282 | 286 |
| Body Mass (g) | 116 | 117 | 118 | 118 | 132 | 139 | 164 | 170 | 240 |
| Face Mass (g) | 34 | 37 | 38 | 38 | 38 | 39 | 41 | 41 | 41 |
| Toe W (g) | 38 | 45 | 50 | 55 | 61 | 60 | 61 | 63 |
| Heel W (g) | 34 | 32 | 31 | 31 | 20 | 20 |
| Steel Mass % | 70 | 68 | 67 | 66 | 68 | 70 | 78 | 78 | 100 |
| W Mass % | 30 | 32 | 33 | 34 | 32 | 30 | 22 | 22 |
| Steel vol. % | 80 | 79 | 78 | 77 | 80 | 81 | 86 | 86 | 100 |
| W vol. % | 20 | 21 | 22 | 23 | 20 | 19 | 14 | 14 |
|
| TABLE III |
|
| Club Number | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | P |
|
|
| loft | 17 | 20 | 23 | 26 | 29 | 33 | 37 | 41 | 45 |
| Blade Length | 77.6 | 77.6 | 77.6 | 77.6 | 77.6 | 77.6 | 77.6 | 77.6 | 77.6 |
| (mm) |
| Toe Height | 51.9 | 52.3 | 52.8 | 53.3 | 53.8 | 54.3 | 54.9 | 55.4 | 55.8 |
| (mm) |
| Scoreline Width | 53.2 | 53.0 | 52.8 | 52.7 | 52.5 | 52.3 | 52.2 | 52 | 51.8 |
| (mm) |
| Scoreline to | 17.3 | 17.5 | 17.7 | 17.8 | 18 | 18.2 | 18.3 | 18.5 | 18.7 |
| Toe (mm) |
| Hosel Length | 62 | 63 | 64 | 65 | 66 | 67 | 68 | 69 | 70 |
| (mm) |
| Sole Width | 19.7 | 19.4 | 19.0 | 18.5 | 18.0 | 17.4 | 16.8 | 16.1 | 15.4 |
| (mm) |
|
As shown inFIG. 3 and set forth in Table III above, another embodiment of the present invention includes a set of irons that have a substantially constant Blade Length (BL) throughout the set. The BL is defined at the length from the hosel axis (HA) intersection with the ground plane to the end of the toe. However in this set, the Toe Height (TH) progressively increases through the set. Thus, the TH of the mid iron is greater than the TH of the long iron and the TH of the short iron is greater than the TH of the mid iron and the long iron. The TH is defined as the maximum length from the leading edge to the top of the toe in the plane parallel to the face plane and perpendicular to the scorelines. Preferably, the TH increases by about at least 0.3 mm per club, and most preferably at least 0.4 mm per club. Also, the TH preferably increases at least 1 mm per club (or about 4 degrees of loft) for the short irons and only 0.3-0.6 mm per club for the long and mid irons.
Furthermore, even though the BL remains substantially constant through the set, the scoreline width (SLW) progressively decreases through the set and the scoreline to toe width (SLTW) progressively increases through the set. More particularly, the SLW decreases by at least about 0.1 mm per club (or per 4 degrees of loft). Thus, the SLW for the long iron is greater than the SLW for the mid iron and the SLW for the mid iron is greater than the SLW for the short iron. Moreover, because the SLTW progressively increases through the set, the non-grooved toe area increases throughout the set.
Still further, in this preferred embodiment of the present invention, the distance of the center of gravity from the face center progressively increases through the set. Thus, CG-Xfc progressively increases from less than 2 mm from the face center in the long irons to about 3 mm from the face center towards the hosel in the short irons.
Another aspect of the present invention is that the hosel length HL increases through the set. Preferably, the hosel length increases by about 1 mm/club (or per 4 degrees of loft) such that the HL of the mid irons is greater than the HL of the long irons and the HL of the short irons is greater than the HL of the mid irons. Also, the sole width, not shown in the figures because it is the width of the sole at the center of the club head perpendicular to the fornt view shown inFIG. 3, decreases through the set. Thus, the sole width of the mid irons is less than the sole width of the long irons and greater than the sole width of the short irons. Preferably, the sole width decreases by about 0.3 mm/club (or per 4 degrees of loft).
As shown inFIGS. 4-7 and set forth in the table above, the set includes along iron100, amid iron200, a firstshort iron300 and a secondshort iron400. InFIG. 4, thelong iron100 includes abody member110,heel112, atoe114, ahosel116 and a sole118. Theiron body110 includes aninsert aperture120 and ahollow portion122. A face insert, not shown, is welded to theinsert aperture120 to enclose thehollow portion122. Both thebody member110 and the face insert are preferably formed of steel. Inside thehollow portion122, a tungstentoe weight member124 and a tungstenheel weight member126 are located proximate thetoe114 and theheel112, respectively, to create a high moment of inertia. As shown in Table II above, thebody member110 preferably has a mass of about 110 grams to 120 grams and the face insert has a mass of about 30 grams to 45 grams. In thelong irons100, thetoe weight member124 preferably has a mass of about 35 to 55 grams. Preferably, thetoe weight member124 mass increases with each club by about 5 grams per club. Theheel weight member126 is preferably about 30 grams to 35 grams and preferably decreases by about 1 or 2 grams per club. Preferably, the tungsten mass of thetoe weight member124 and theheel weight member126 are at least 25% of the total club head mass and at least 15% of the total club head solid volume. More particularly, thetoe weight member124 and the heel weight member comprise about 30% of the total mass or more and 20% of the total solid volume. Preferably, thetoe weight member124 has greater mass than theheel weight member126.
As shown inFIG. 5 and set forth in Table II above, the set includes amid iron200 that includes abody member210,heel212, atoe214, ahosel216 and a sole218. Theiron body210 includes aninsert aperture220 and ahollow portion222. A face insert, not shown, is welded to theinsert aperture220 to enclose thehollow portion222. Both thebody member210 and the face insert are preferably formed of steel. Inside thehollow portion222, a tungstentoe weight member224 and a tungstenheel weight member226 are located proximate thetoe214 and theheel212, respectively, to create a high moment of inertia. As shown in Table II above, thebody member210 preferably has a mass of about 115 grams to 145 grams and the face insert has a mass of about 30 grams to 45 grams. In themid irons200, thetoe weight member224 preferably has a mass of about 50 to 70 grams. Preferably, thetoe weight member224 mass increases with each club by about 5 grams per club. Theheel weight member226 is preferably about 35 grams or less and preferably decreases per club. Preferably, the tungsten mass of thetoe weight member224 and theheel weight member226 are at least 25% of the total club head mass and at least 15% of the total club head solid volume. More particularly, thetoe weight member224 and theheel weight member226 comprise about 30% of the total mass or more and about 20% of the total solid volume. Preferably, thetoe weight member224 has greater mass than theheel weight member226, and more preferably, is about twice the amount of mass.
As shown inFIG. 6 and as set forth in Table II above, the set can include ashort iron300 that includes abody member310,heel312, atoe314, ahosel316 and a sole318. Theiron body310 includes aninsert aperture320 and ahollow portion322. A face insert, not shown, is welded to theinsert aperture320 to enclose thehollow portion322. Both thebody member310 and the face insert are preferably formed of steel. Inside thehollow portion322, a tungstentoe weight member324 is located proximate thetoe314, to create a high moment of inertia. As shown in Table II above, thebody member310 preferably has a mass of about 150 grams to 200 grams and the face insert has a mass of about 30 grams to 45 grams. In theshort iron300, thetoe weight member324 preferably has a mass of about 55 to 70 grams. Preferably, the tungsten mass of thetoe weight member324 is at least 20% of the total club head mass and at least 10% of the total club head solid volume.
As shown inFIG. 7 and as set forth in Table II above, the set can include ashort iron400 that includes abody member410,heel412, atoe414, ahosel416 and a sole418. Theiron body410 includes aninsert aperture420. A face insert, not shown, is welded to theinsert aperture420. Theshort iron400 is preferably substantially solid and does not contain tungsten weight members.
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. Therefore, it will be understood that the appended claims are intended to cover all modifications and embodiments which would come within the spirit and scope of the present invention.