Golf Club Head With Weight Adjusting Means

Abstract

A golf club having provision for adjusting the swing weight and balance of the club. The club head includes a cavity adapted to removably receive a module mounting one or more threaded shafts. The shafts are threadedly retained in the module and may be withdrawn therefrom to receive a plurality of threaded nuts or weights. The nuts may then be rotatably translated along the shaft or shafts to provide a finite adjustment of the swing weight and/or balance.

Description

The present invention relates to a golf club, and more particularly, to a golf club head having provision for easily changing the swing weight and/or balance of the head.

It is well known that golfers are highly individualistic in the selection of their clubs and that it is conventional for a golfer to select a set of clubs on the basis of a particular length, a particular swing weight, and a balance which suits his individual preference. While the club length for a particular golfer will not normally change, it often happens that after the purchase of a set of clubs, the golfer will find that either the swing weight or balance, or both, is not to his liking, and he will want to have them changed.

In determining the swing weight of a golf club, it is conventional practice to horizontally position the club on a "swing weight" scale having a fulcrum positioned intermediate the ends of the club such that the head end is left unsupported. The swing weight is then determined from the upwardly directed force at the grip end of the club resulting from the moment of the club head portion of the club about the fulcrum. It will therefore be seen that the swing weight is a function of both the total weight of the head, as well as the length of the moment arm from the club head portion's center of gravity to the fulcrum. Thus any change in the weight of the club head or a change in the length of the moment arm will change the swing weight of the club.

In the past, a change in weight of the club head has been usually accomplished by drilling a hole in the club head, and either leaving it void if the weight is to be reduced, or filling it with a heavy material, such as lead, if the weight is to be increased. It will be appreciated that this manner of adjusting the swing weight is not very satisfactory in that it does not provide a very finite or sensitive adjustment. In addition, the adjustment is irreversible in that once the hole is drilled, the club may never be returned to its original characteristics.

Heretofore, a change in the length of the moment arm to vary the swing weight of a club has not been possible except in connection with clubs having specially constructed club heads thereon. Such specially constructed club heads must be custom made and are either entirely hollow or have intricately formed cutouts therein.

Another area of individual golfer preference is the "balance" of the club head, which as used herein refers to the distribution of weight within or the position of the center of gravity of the club head parallel to the base plate and perpendicular to the face of the club head. The balance of a club head may be changed by shifting the center of gravity thereof toward or away from the face of the club head without appreciably changing the swing weight thereof.

While it has been previously proposed to position an adjustable weight within the head of a golf club to vary its balance, all known designs also require a specially constructed club head to accommodate the weight as discussed above. None of these known designs are adapted for incorporation in a conventional club head.

Accordingly, it is an object of the present invention to provide a device for changing the weight and/or balance of a golf club and which is adapted for use with a club of conventional design after only a slight modification to the club head. In this regard, the device of the present invention comprises a module having adjustable weighting means therein which is adapted to be mounted in a conventional golf club by merely forming an aperture or cavity in the head.

It is a further object of the present invention to provide a self-contained module which may be removably mounted in the head of a conventional golf club, the module including weights therein which may be either entirely removed or selectively shifted to different positions within the club head.

It is a further object to provide a means for adjusting the weight or balance of a golf club which does not change the outer appearance of the club and which will not be apparent from a visual examination.

These and other objects and advantages of the present invention are achieved in the embodiment of the invention described herein through the provision of a golf club comprising an elongated shaft with an enlarged, substantially solid head carried at one end. The head includes a relatively flat base surface, a generally vertically extending striking face, and a cavity communicating with the base surface. An externally threaded member is mounted within the cavity along an axis substantially perpendicular to the striking face, and an internally threaded member is positioned on the externally threaded member. The internally threaded member is adapted to be selectively positioned along the length of the externally threaded member to adjust the distribution of weight in the head and hence the balance thereof. Also, the externally threaded member may be removably mounted in the cavity such that additional internally threaded members may be positioned on the externally threaded member to increase the total weight of the head and hence the swing weight thereof.

Some of the objects and advantages of the invention having been stated, others will appear as the description proceeds, when taken in connection with the accompanying drawings, in which

FIG. 1 is an exploded perspective view illustrating the weight-adjusting means of the present invention positioned in the bottom face of a golf club head.

FIG. 2 is a sectional view of the golf club head taken substantially along the line 2--2 of FIG. 1.

FIG. 3 is a sectional view of the golf club head taken substantially along the line 3--3 of FIG. 2.

FIG. 4 is a sectional view similar to FIG. 3, of a club head illustrating a second embodiment of the present invention.

FIG. 5 is a sectional perspective view of one embodiment of an adjustable weight utilized in the present invention.

A golf club 10 including a club head 12 embodying the teachings of the present invention is illustrated in the drawings. It will be appreciated that the club head 12 is attached to an elongated shaft (not shown) in a conventional manner.

The outer configuration of the head is conventional in that it includes a relatively flat bottom or base surface 14, a transversely extending and somewhat upwardly inclined forward striking face 16, a top surface 18, and a rear surface 20. A metallic sole or baseplate 22 is attached to the base surface by a number of screws 24.

Centrally positioned in the head 12 above the soleplate 22 and communicating with the base surface is a generally rectangular cavity or cutout 25 which may be formed in the club during its manufacture or at any time subsequent thereto. In the embodiment shown in FIGS. 1-3, the cavity 25 will be seen to be somewhat elongated with the lengthwise dimension substantially parallel to the base surface 14.

The cavity 25 is adapted to frictionally receive and retain an open-ended rectangular module 26 which substantially conforms to the configuration of the cavity. Two opposed parallel walls, 27 and 28, of the module 26 include three pairs of aligned apertures 29 and 30, respectively, with apertures 29 being internally threaded. In the illustrated embodiment, two externally threaded members or shafts 32 are mounted in the module 26 and are threadably received in apertures 29. Each shaft 32 mounts two adjustable weights in the form of internally threaded members or nuts 34. The module 26 further includes a pair of opposed end walls 36, each of which includes an aperture 37 for facilitating removal of the module in a manner hereinafter further described.

One end of each shaft 32 includes a screwdriver slot 38 for effecting rotation thereof. Thus, when the module 26 is removed from the cavity 25, the shaft 32 may be rotated and thereby released from the module wall 27. The shaft 32 is then free to have one or more weights removed, or to have additional weights added.

It will be appreciated from the above description that the swing weight and/or balance of the club may be adjusted by removing the soleplate 22 and either rotatably translating the weights 34 to a different location on the shafts 32, or by increasing or decreasing the number of weights on each shaft. As set forth above, the latter operation is effected by removing the module 26 from the head and rotating the shaft 32 until it is free from one wall thereof. Also, it will be noted that the module 26 is adapted to accommodate up to three shafts. Thus the swing weight may be changed by adding or subtracting a shaft from the module or by changing the position of a shaft within the module.

To restrain inadvertent rotation of the weights 34 relative to shafts 32, a circumferential thread engaging resilient insert 40 may be suitably mounted in the bore of the weight to act as a thread lock, note FIG. 5. To supplement, or as an alternative for the locking insert 40, a resilient washer 42 may be mounted between adjacent weights in the manner illustrated in FIG. 3. The washer 42 preferably frictionally engages the threads of the shaft 32 to thereby inhibit rotation of the adjacent weights.

A second embodiment of the present invention is illustrated in FIG. 4. In this instance, a module 26' is removably mounted in a vertically disposed elongated cavity 25' in the club head, the cavity having a lengthwise dimension substantially perpendicular to the base surface 14. In this instance, the aperture 37' in the lower end wall 36' is designed to receive a suitable tool (not shown) to facilitate withdrawal of the module from the cavity 25' after removal of the soleplate 22'. It will be also noted that in the embodiment of FIG. 4, a locking washer 42' is mounted on each side of each weight 34' to restrain rotational translation. The use of the washers 42' in this manner may supplement or replace the internal locking ring 40 as shown in FIG. 5.

From the drawings, it will be observed that the axis of each shaft 32 extends substantially perpendicular to the striking face 16 (when the inclination of the face is disregarded). In other words, the axis will lie substantially parallel to the direction of club head travel during the swing. This feature is desirable in that it results in a concentration of weight immediately behind the ball to produce longer drives, and it also minimizes the torque transmitted through the club head at impact.

While the preferred embodiments of the present invention have been described in considerable detail herein, it will be understood that various modifications could be made without departing from the spirit of the invention. For example, the modules 26 and 26' have been illustrated as being somewhat rectangular and with two open ends. Obviously, any suitable outer configuration could be employed, and one end could be closed to provide added strength if so desired. Also, the module could be designed to accommodate less than three shafts if so desired.

In the drawings and specification, there have been set forth preferred embodiments of the invention, and although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

I claim:

1. A golf club comprising,

an enlarged, substantially solid head including a relatively flat base surface and a transversely extending striking face, and having a cavity communicating with said base surface,

a removable module positioned within said cavity, said module including opposed walls extending substantially parallel to said striking face, at least one externally threaded member mounted on said opposed walls, and at least one internally threaded member threadedly positioned on said externally threaded member, said internally threaded member adapted to be selectively translated along the length of said externally threaded member by rotation thereof to adjust the distribution of weight in said head, and

a soleplate closing said cavity and providing access to said module therein.

2. The golf club as defined in claim 1 wherein said externally threaded member is removably mounted on said opposed walls whereby a plurality of internally threaded members may be selectively positioned on said externally threaded member to vary the swing weight of said golf club.

3. The golf club as defined in claim 2 wherein said externally threaded member is mounted along an axis substantially perpendicular to said striking face.

4. The golf club as defined in claim 2 wherein said cavity is elongate and has a lengthwise dimension substantially parallel to said base surface.

5. The golf club as defined in claim 2 wherein said cavity is elongate and has a lengthwise dimension substantially perpendicular to said base surface.

6. The golf club as defined in claim 2 wherein the outer periphery of said module substantially conforms to the configuration of said cavity.