US3897065A

US3897065A - Golf club head with improved sole and toe portions

Info

Publication number: US3897065A
Application number: US438281A
Authority: US
Inventors: Karsten Solheim
Original assignee: Karsten Solheim
Current assignee: Karsten Manufacturing Corp
Priority date: 1974-01-31
Filing date: 1974-01-31
Publication date: 1975-07-29
Anticipated expiration: 1992-07-29

Abstract

A trailing portion of the sole of a golf club head is beveled upwardly relative to a horizontal plane to form a ridge along the sole. The sole of each club of a set is at a progressively greater angle relative to a vertical plane passing through the axis of the club shaft and parallel to the leading edge of the club head along a central portion of the striking face of the golf club head, and the progression from club to club of the set is in the order of increasing loft angle. A trailing surface portion of the toe and heel is similarly beveled rearwardly and inwardly toward each other to form toe and heel ridges that blend with the sole ridge. The toe and heel are also beveled forward of the ridge in the direction of the striking face.

Description

United States Patent [191 [111 3,897,065

Solheim 1 July 29, 1975 [54] GOLF CLUB HEAD WITH IMPROVED SOLE Dl97,524 2/1964 Behrendt D34/5 Gl-l AND TOE PORTIONS [76] Inventor: Karsten Solheim, 10412 N. 37th St.,

Phoenix, Ariz. 85028 [22] Filed: Jan. 31, 1974 [21] App]. No.: 438,281

[52] U.S. Cl 273/167 A; 273/167 F [51] Int. Cl A63b 53/04 [58] Field of Search 273/77 R, 80 C, 163 R, 273/164, 167l75;D34/5 GC, 5 GH [56] References Cited UNITED STATES PATENTS 1,139,738 5/1915 Tyler 273/167 A 2,332,342 10/1943 Reach.... 273/171 2,683,036 7/1954 Klein 273/167 G 2,820,638 l/1958 Morrison 273/164 3,079,157 2/1963 Turner 273/167 A 3,088,736 5/1963 Mospan 273/167 A X 3,655,188 4/1972 Solheim 273/80 C D79,553 10/1929 Foard.... D34/5 GC Dl79,590 l/l957 Carper 273/164 X D2l5,608 10/1969 Lysaght 273/167 A UX Primary Examiner Richard J. Apley Attorney, Agent, or Firm-Lindenberg, Freilich, Wasserman, Rosen & Fernandez [57] ABSTRACT A trailing portion of the sole of a golf club head is beveled upwardly relative to a horizontal plane to form a ridge along the sole. The sole of each club of a set is at a progressively greater angle relative to a vertieal plane passing through the axis of the club shaft and parallel to the leading edge of the club head along a central portion of the striking face of the golf club head, and the progression from club to club of the set is in the order of increasing loft angle. A trailing surface portion of the toe and heel is similarly beveled rearwardly and inwardly toward each other to form toe and heel ridges that blend with the sole ridge. The toe and heel are also beveled forward of the ridge in the direction of the striking face.

1 Claim, 6 Drawing Figures GOLF CLUB HEAD WITH IMPROVED SOLE AND TOE PORTIONS BACKGROUND OF THE INVENTION This invention relates to an improved head for golf clubs, designed more particularly for use in connection with a correlated golf club set as disclosed in my U.S. Pat. No. 3,655,188, but having utility also in connection with other clubs.

In the aforesaid patent there is disclosed a correlated set of golf clubs of the type commonly referred to as irons. An important feature of that set is that the angle of the sole of each club of a set (measured relative to a vertical plane passing through the axis of the club shaft and parallel to the leading edge of the club head along a central portion of the striking face of the golf club head) is correlated with loft and lie. The sole angle for the golf club of the set having the smallest loft angle is the smallest for the set and is less than 90, while the sole angle for the golf club having the greatest loft angle is the greatest for the set and is greater than 90. For intermediate golf clubs of the set in terms of loft, the sole angle is increased as the loft angle is increased such that for a golf club selected from about the middle of the set, when arranged in increasing order of loft, has a sole angle most nearly equal to 90.

An advantage of having the sole angle correlated with the loft in that manner is that, with a sole angle progressively greater than 90 for golf clubs having a progressively greater loft angle than the middle club of the set, contact of the sole of the club with the ground during a stroke will cause the club head to move upwardly progressively more for a progressively greater loft angle. The result is that the striking face of the golf club will be in contact with the ball progressively longer for progressively greater loft in order to provide progressively more back spin on the ball. This is desirable with golf clubs of higher loft used on approach shots onto the putting green.

Golf clubs of progressively lower loft than the one at the middle of the set are used more often for long shots off the tees and the middle of the fairway, when distance is more important than position, rather than for approach shots. Back spin is usually not desired for long shots. Instead, it is desired that the ball be allowed to run on the fairway toward the green. Therefore, golf clubs of progressively smaller loft than the middle club of a correlated set are provided with sole angles progressively less than 90 when made in accordance with my aforesaid patent.

At impact, the ball is flattened out against the face of the club. Thereafter, due to elasticity, the ball begins to resume its round shape, thus propelling itself in a direction very nearly normal to the club face (assuming no spin about a vertical axis of the ball). It is during this period of propulsion that the feature of a correlated sole angle has its greatest effect because the greater the loft the greater the bounce of the club head and, therefore, the greater the period of contact with the ball. However, the swing of the golf club should not stop when the ball leaves the club face. For a perfect swing, the golfer must follow through smoothly after impact. It would be desirable to provide a configuration for the club head which facilitates the follow through without detracting from the performance of the club in other respects, particularly the correlated bounce effect when it is provided.

As just noted, the elasticity of the ball propells it in a direction that is nearly normal to the striking face, but not quite because at the moment of impact, the golf club head is cutting across a line in the direction of the intended line of flight, i.e., across a line on the ground in a direction normal to the club head at the moment of impact, assuming a stroke with the face of the club square and not open" or closed (turned clockwise or counterclockwise by a right handed golfer) deliberately for an intentional hook or slice. The club head cuts across from the other side of that line relative to the golfer to the near side of the line. The fact that the club head is cutting across can be verified by observing the sole of any golf club that has been extensively used by a consistent golfer. It will be marked with scratch lines that are off from a direction normal to the club face by a small angle. It would be desirable to provide a configuration for the toe of the club head which will facilitate the follow through and at the same time permit effectively extending the length of the club head from the heel to the toe without altering the size or shape of the striking face. This has the effect of distributing more weight further out on the toe to maximize the size of the sweet spot.

SUMMARY OF THE INVENTION In accordance with the present invention in its broadest aspects, a trailing portion of the sole of a golf club of the iron type is beveled upwardly relative to a horizontal plane to form a ridge along the sole. The trailing portion refers to a substantial portion of the sole (at least one-third the width of the sole from the toe to the heel) farthest away the leading edge of the club head, the leading edge being where the striking face joins the sole of the golf club. The end of the toe is similarly beveled throughout in the trailing surface portion thereof by a small acute angle relative to a normal to the striking face. That bevel in the trailing portion of the toe forms a ridge that blends in with the ridge on the sole where the sole turns upwardly to merge with the toe end. The leading surface portion of the end of the toe, between the ridge and the striking face, is also beveled by a small acute angle in a direction opposite the bevel in the trailing portion of the toe end of the club head to form a ridge that blends with the sole ridge. The bevel in that leading portion of the end of the toe is selected to be approximately equal to the angle by which the club head cuts across a line normal to its striking face at the moment of impact during a normal golf swing. The heel end is similarly beveled in leading and trailing portions to form a ridge that blends with the sole ridge.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a rear view of a No. 5 iron.

FIG. 2 is a front (toe) end view of the No. 5 iron of FIG. 1.

FIG. 3 is a front (toe) end view of a No. 3 iron.

FIG. 4 is a bottom (sole) view of the No. 5 iron of FIG. 1.

FIG. 5 is a front (toe) end view of a No. 9 iron.

FIG. 6 is a front (toe) end view of a No. 11 iron.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring to the drawings, selected clubs of a set correlated in accordance with my aforesaid U.S. Pat. No. 3,655,188 are shown. The clubs selected are the Nos.

3, 5, 9 and l I. By th -mselves, they constitute a short set, which is all that some golfers carry, although it is more customary to carry a more complete set, usually clubs numbered 2 or 3 through 11, and sometimes including a No. 1. This is, of course, besides the woods customarily carried.

The No. 5 iron shown in FIGS. 1 and 2 will first be described as representative of the set. It comprises a head having a hosel 11. A shaft 12 (shown broken away) is rigidly attached to the hosel as an extension thereof in the usual manner. The shaft extends at an angle C measured in a vertical plane passing through the axis 13 parallel to the central portion of a leading edge 14 (FIG. 2) of a planar striking face 15. The angle c is commonly defined as the lie of the club, is measured from a horizontal plane that is perpendicular to the vertical plane that passes through the central portion of the leading edge 14. The horizontal and vertical planes are represented by lines H and V in FIGS. 1 and 2. The horizontal plane is normal to the plane of the paper in both instances, and the vertical plane is parallel to and normal to the plane of the paper in respective FIGS. 1 and 2.

The loft angle A of the club is measured as shown in FIG. 2 from the vertical plane to the plane of the striking face 15. That angle is about 28for a No. 5 iron, but may differ among manufacture by a few degrees. The lie, angle C, is about 61, but again may differ among manufactures. What is consistent among all manufactures is that lie is increased as loft is increased in irons from No. 1 through 9. In irons of greater loft, the same lie is usually maintained as for a No. 9.

If all clubs of a set are arranged in increasing order of loft, the central club in the group from No. 1 through No. 9 is the No. 5 and may therefore be referred to as a midrange club. The remaining

clubs

10 and 11 are specialty clubs commonly referred to as sand and pitching wedges, but are nevertheless to be correlated with loft as to a sole angle in accordance with my aforesaid patent. However, the choice of the No. 5 as the midrange club is not essential; the No. 6 iron could, for example, be selected as the midrange club.

In accordance with my prior patent, golf clubs of the set arranged in increasing order of loft angle are provided with a progressively greater sole angle, where the sole angle is an angle measured from the vertical plane to a sole plane S tangent to the sole l6 and parallel to the central portion of the leading edge 14 of the club head. In the case of the midrange club, the sole angle is selected to be equal to 90, or very nearly so, such that the angle between the horizontal plane and the sole plane is equal to or substantially equal to 0 as shown in FIG. 2. For irons of smaller loft than the loft of the midrange club, the sole angle is less than 90 as shown in FIG. 3 for a No. 3 iron. The complementary angle B is shown for convenience, it being understood that the sole angle is 90 i B. Since the angle B is negative for a club of smaller loft than the midrange club as shown, the sole angle is by this designation less than 90. For a club of greater loft than the midrange club, the angle B is positive for a sole angle greater than 90, as shown in FIGS. 5 and 6 for the No. 9 and No. 11 irons.

The improvement over my prior invention with respect to the sole angle is a bevel in the trailing portion 16 of the sole 16 which leaves a ridge 17 extending from the toe 18 to the heel l9 everywhere approximately midway between the leading edge 14 and the trailing edge 20 of the sole as shown in FIG. 4 for the midrange club and passing through the neutral axis of the club head. The neutral axis is a plumb line from a point at approximately the middle of the grip (not shown) when the club is suspended from that point.

The bevel on the sole is preferably a small angle of about 15 as shown by the angle D in FIG. 2. Approximately the same bevel is provided with respect to the sole 16 for all clubs. The result of the bevel is to reduce the dragging effect of the trailing edge as the club head passes through the turf particularly in the follow through after impact with the ball. The bounce (positive and negative) effect of the sole angles (+8 and B) is retained to substantially the same advantage as before since that comes into play mostly before the drag effect would begin to take effect, i.e., before the trailing portion 16' passes very far into the turf. Once the trailing portion 16' fully penetrates the turf, this improvement comes fully into play.

Although this improvement has been shown and described with reference to a correlated golf club set as disclosed in my prior patent, it should be understood that the same improvement may be provided to advantage in golf clubs of other configurations not having a correlated sole angle, or having a sole angle that is constant (uniform) for every club of the set (usually equal to except for the wedges of the set, Nos. 10 and 11). Consequently, the appended claims are intended to include this improvement in such other configurations.

Another improvement which can be used in conjunction with the improvement just described, or used independently, concerns the configuration of the toe. The toe is beveled toward the shaft in a trailing surface portion 18' by a small acute angle E (about equal to the bevel of the sole) measured relative to a normal to the striking face leaving a ridge 21 which merges with the ridge 17 of the beveled sole at a rounded corner 22 shown in FIG. 1. The surface portion of the toe between the ridge 21 and the striking face is beveled by a small acute angle F measured relative to a normal to the striking face but in the opposite direction.

The acute angle F is selected to be equal to the angle between the expected direction of swing and the direction in which a normal to the striking face is pointing at the moment of impact due to the fact that the average golfer has a swing that cuts across from the outside to the inside of a vertical plane passing through the ball center and normal to the club face at the moment of impact, the outside being the side away from the golfer. This obviously will vary with different golfers, but will always be on the order of 8. Consequently, an angle of about 8 would be adequate for the average golfer. The effect of this bevel is to terminate the end of the club face with a toe having a surface parallel to the direction of swing, thus extending the club head at the toe without increasing the length of the striking face from heel to toe, and without presenting any added turf resistance to the motion of the club head during impact. The bevel in the trailing portion 18 is less important but is nevertheless significant in decreasing drag.

An additional advantage of this configuration is that it allows moving additional weight out on the toe, thus lengthening the sweet spot. The sweet spot is the area on the striking face which can be used to strike the ball without producing appreciable torque due to the moments of force involved in striking the ball on a point of the striking face not precisely in front of the centroid of the club head.

In the preferred embodiment shown, the bevel of the surface 16 of the sole is extended around the heel 19 to provide a rearwardly beveled surface 19 on the trailing surface portion of the heel 19 to form a ridge 23. The other side of the ridge 23 extending is beveled up on the heel on the leading surface portion of the heel 19 to provide a surface 19'. The advantage of these

beveled surfaces

19 and 19" is to minimize the forces of blades of grass against heel portions of the club head, particularly the beveled surface 19", which is on the leading side of the ridge 23 which extends around the heel l9 and merges with the ridge 17, as shown in FIG. 4.

What is claimed is:

1. An improved club head for golf clubs of the type commonly referred to as irons used for hitting a ball into an airborne trajectory from a fairway comprising a metal blade having a striking face between a toe and heel, and having a hose] to receive a shaft at said heel, and a relatively wide sole between said toe and heel, said sole connecting with said striking face at a leading edge, a trailing portion of said sole most remote from said leading edge being beveled rearwardly relative to said striking face and upwardly relative to a horizontal plane, said horizontal plane passing through the central portion of said leading edge in a position normal to a vertical plane, said vertical plane passing through the axis of said shaft in a position parallel to said central portion of said leading edge, said sole bevel leaving a ridge extending from said heel to said toe, said club head having a trailing surface portion of said toe most remote from said striking face beveled rearwardly relative to said striking face and inwardly relative to a plane tangent to said toe and normal to said vertical plane, and wherein a surface portion of said toe between said trailing surface portion thereof and said striking face is beveled forwardly relative to said trailing surface portion and inwardly relative to said plane tangent to said toe to leave a toe ridge, said toe ridge blending in with said sole ridge, said toe ridge being located on said toe approximately midway between leading and trailing edges thereof and said sole ridge being located on said sole at least half way from said leading edge of said sole to a trailing edge of said sole.

Claims

1. An improved club head for golf clubs of the type commonly referred to as irons used for hitting a ball into an airborne trajectory from a fairway comprising a metal blade having a striking face between a toe and heel, and having a hosel to receive a shaft at said heel, and a relatively wide sole between said toe and heel, said sole connecting with said striking face at a leading edge, a trailing portion of said sole most remote from said leading edge being beveled rearwardly relative to said striking face and upwardly relative to a horizontal plane, said horizontal plane passing through the central portion of said leading edge in a position normal to a vertical plane, said vertical plane passing through the axis of said shaft in a position parallel to said central portion of said leading edge, said sole bevel leaving a ridge extending from said heel to said toe, said club head having a trailing surface portion of said toe most remote from said striking face beveled rearwardly relative to said striking face and inwardly relative to a plane tangent to said toe and normal to said vertical plane, and wherein a surface portion of said toe between said trailing surface portion thereof and said striking face is beveled forwardly relative to said trailing surface portion and inwardly relative to said plane tangent to said toe to leave a toe ridge, said toe ridge blending in with said sole ridge, said toe ridge being located on said toe approximately midway between leading and trailing edges thereof and said sole ridge being located on said sole at least half way from said leading edge of said sole to a trailing edge of said sole.