US3913911A

US3913911A - Tennis racket with head frame weighting means

Info

Publication number: US3913911A
Application number: US432075A
Authority: US
Inventors: Kenneth Alan Peterson
Original assignee: Individual
Current assignee: Individual
Priority date: 1974-01-09
Filing date: 1974-01-09
Publication date: 1975-10-21
Anticipated expiration: 1992-10-21

Abstract

Attachable and detachable weights are applied to a racket frame at a distance from the geometric axis that passes through the center of the racket handle, in such a manner as to adjust and increase the racket''s moment of inertia about that axis for normal play, and to alter the weight and the head-to-handle balance of the racket for normal play. This unique placement of the weights increases the effectiveness of the weights.

Description

United States Patent Peterson Oct. 21, 1975 [5 TENNIS RACKET WITH HEAD FRAME 3,625,512 12/1971 Latham Ct al 273/73 c WEIGHTING MEANS 3,642,283 2/1972 Wilkens 273/73 C X 3,801,099 4/1974 Lair 273/73 D X [76] Inventor: Kenneth Alan Peterson, 12530 8th Northwest, Seattle, w FOREIGN PATENTS OR APPLICATIONS 98177 17,636 8/1929 Australia 273/73 J 20,747 9/1909 United Kin dom 273/171 [22] Flled 1974 132,698 9/1919 United Kingdom." 273/73 c 21] Appl No: 432 075 848,826 8/1970 Canada 273/73 C 310,350 4/1929 United Kingdom 273/73 C [52] [1.5. Cl 273/73 C Primary Examiner RichaI-d Apley [51] Int. Cl. A63B 49/04 [58] Field of Search 273/73 R, 73 C, 73 D, 165,

273/171, 193 R, 194 R, 73 11, 73 J [57] ABSTRACT Attachable and detachable weights are applied to a [56] References Cited racket frame at a distance from the geometric axis UN STATES PATENTS that passes through the center of the racket handle, in 1 453 503 5/1923 Holmes 273/171 Such a manner as to adjust and increase the rackets 135391019 5H925 Nikonowm 273/73 C moment of inertia about that axis for normal play, and 1,804,316 5/1931 Butler 273/165 to alter the Weight and the head-to-handle balance of 2,655,669 10/1953 Schaper 273/165 UX the racket for normal play. This unique placement of 3,143,349 8/1964 Maclntyre. 273/171 the weights increases the effectiveness of the weights. 3,305,235 2/1967 Williams 273/73 C X 3,330,560 7/1967 Higdon 273/171 x 1 Claim, 4 Drawmg Figures 24 ELASTOMERIC WEIGHT ELASTOMERIC WEIGHT WEIGHTS US. Patent Oct. 21, 1975 ELASTOMERIC WEIGHT 23 WEIGHTS WEIGHTS ELASTOMERIC WEIGHT f 22 WEIGHTS TENNIS RACKET wm HEAD FRAME WEIGHTING'YMEANSY BACKGROUND. F. i-N v aurlon This invention provides p'ersoii'swith a meansto irnprove the performance of tnni s rack'et or"such, en-' abling the person to match the rackets 'playingperfo'n" mance with personal preferences, these'preferences being variable and dependent upon environmental co'nditions, players physical condition and current'playing nent insertion of a weighted plug into the handle. Al-

though this plug adjusts the head-to-handle balance of the racket, it is on the axis of the handle and thus has only a small effect on the moment of inertia about that purposeful and convenient adjustment of this torsional moment of inertia.

This invention also allows convenient and independent adjustment of the weight and head-to-handle balance of the racket. Previously a device had been proposed which employed a single sliding weight in the racket handle. This device altered the balance conveniently, but did not allow adjustment of the mass of the racket. Its effect on the torsional moment of inertia was negligible. Another proposed device consisted of a laced-on practice weight on the central (handle) axis of the racket. It was not envisioned for use in normal play, and was neither convenient to change nor of an appropriate weight to be used in normal play. It's position was inappropriate for adjustment of the torsional moment of inertia.

Until now, selection of a racket that best fit the players needs was essentially a process of trying different, fixed rackets until encountering a racket that felt best. The differences in weight in question are relatively small. There is only a 17 percent difference between the lightest and heaviest of the recommended adult rackets. Within these small weight differences, too light a racket makes it difficult to obtain a smooth follow-through and unnecessarily strains the racket and the arm muscles during impact with the ball. Too heavy a racket, while imparting more momentum to the ball, generally results in slow stroking and unnatural tiredness of the playing arm. Most ranking players prefer a handle-heavy racket, but preferences vary, and have been one basis of selection of the preferred playing response of a racket. Some players had considerable funds or sponsors which would provide a wide range of rackets to try and select through a process of trial and error. The selection by other players was restricted to the few rackets they could try before buying or buy before trying. This narrowed their ability to attain their most preferable racket mass and balance.

SUMMARY OF INVENTION v v v A player of tennis or another racket sport playswith a racket which has provision to add weights to its frame, ata position distant from the central axis which passes through the center of the racket handle. The

player thus, by adding weights or removing weights, changes the playing response of the rack'et to fit his current preference, through a-process of convenient. trial and'error. Reacting to environmental or physical 'con-' ditions or desire to pursue a different playing style, the

player changes the mass, the head-to-handle balance and thetorsional moment of inertia. (The tendency 'to resist twisting about the axis of the handle.) All these changes are possible because the weights are small enough to be used during normal play, and because the number of weights, the size of the weights, the composition of the weights, the distance of the weights from the end of the handle, and the distance of the weights from the axis of the handle can be changed. The player can, if desired correct a tendency to'hit the ball off cen-' ter to one side by'distribu'ting the weights unevenly on 1 purpose. The weights are firmly attached, but easily removed or changed.

DRAWINGS Preferred embodiments of the invention are illustrated in the accompanying drawings, wherein:

FIG. 1 shows in perspective, a bracket which holds detachable weights, and which can be attached to various points on an ordinary tennis racket by flexible straps.

FIG. 2 shows in perspective, weights which fit into and onto the bracket shown in FIG. 1, and which fit into and onto the provisions in the racket section shown in FIG. 5.

FIG. 3 shows in side elevation, a bracket attached to a tennis racket.

FIG. 4 shows in perspective, a racket with two brackets and a plurality of weights attached to it.

PREFERRED EMBODIMENT The preferred embodiment shown in FIGS. 1, 2, 3 and 4 concerns a method to add the invention to an existing racket.

Bracket And Removable Weights The slot 20 in the bracket 21 is closed at one end to provide the principal opposition to motion of the weights 22 in the slot 20 as the player swings the racket. Other mechanisms acting to keep the weights 22 in the slot 20 are the stiffness of the edges of the slot 20 reacting against the wide retaining base 23 of the weight 22, and the friction between the weight 22 and the bracket 21. If wear from usage results in excessive Iooseness of fit, the last weight 24 inserted in the slot 20 is composed of an elastomeric material and retains the other weights 22.

Bracket Mounting The brackets 21 are held to the racket 25 by flexible straps 28 at positions distant from the central longitudinal axis 34. The bracket 21 deforms enough to fit the curvature of the racket 25 frame. This deformation is allowed by rounded grooves 27 in the base of the bracket 21, and by the plastic material of the bracket 21, and by the angular grooves 37 in the base of the bracket 21. The angular grooves 37 also provide clearance for racket strings which protrude in some constructions, and the angular grooves 37 provide constraint to prevent slippage of the bracket 21 on the racket 25. Slippage of the bracket 21 is further prevented by the mounting straps 26 passing between, and contacting the strings 29 of the recket 25. Straps 26 are retained to-the bracket 21 by tension in mounting and by nesting of straps'26 in groove means 30 and 30A at the ends of the bracket 21. Groove means 30A is configured as a deep rectangle to retain one or more straps 26. Groove means 30 is angular in shape to retain straps 26, and also simplify design of a mold for manufacture of brackets 21.

I claim:

1. In combination, a game racket and weighting means therefor, comprising: said racket having a closed loop head portion and a handle portion extending therefrom, said racket having a central longitudinal axis with said head portion symmetrically disposed thereabout, ,said weighting means being disposed on said head portion at transverse and symmetrical locations relative to said axis, each of said weighting means includes a bracket, a plurality of weights, and a plurality of flexible securement straps, each of said brackets having an outer surface and an inner surface, said outer surface having an upstanding portion, a dead-ended T- shaped slot formed in said'upstanding portion, said slot further having overhanging flanges, said upper surface further including strap receiving groove means located on both ends of said upper surface, at least one of said groove means being disposed at a lower elevation than said slot, said inner surface being configured to conform to the outer curved surface of said head portion, said weights having at least a T-shaped formation and being slidably and removably disposed and frictionally held in said slot for increasing and decreasing the moment of inertia about said axis, said upstanding portion and flanges being of sufficient stiffness to further retain said weights in said slot, said straps being seated in said strap receiving groove means and being secured about said head portion thereby holding said brackets thereto.

Claims

1. In combination, a game racket and weighting means therefor, comprising: said racket having a closed loop head portion and a handle portion extending therefrom, said racket having a central longitudinal axis with said head portion symmetrically disposed thereabout, said weighting means being disposed on said head portion at transverse and symmetrical locations relative to said axis, each of said weighting means includes a bracket, a plurality of weights, and a plurality of flexible securement straps, each of said brackets having an outer surface and an inner surface, said outer surface having an upstanding portion, a dead-ended T-shaped slot formed in said upstanding portion, said slot further having overhanging flanges, said upper surface further including strap receiving groove means located on both ends of said upper surface, at least one of said groove means being disposed at a lower elevation than said slot, said inner surface being configured to conform to the outer curved surface of said head portion, said weights having at least a T-shaped formation and being slidably and removably disposed and frictionally held in said slot for increasing and decreasing the moment of inertia about said axis, said upstanding portion and flanges being of sufficient stiffness to further retain said weights in said slot, said straps being seated in said strap receiving groove means and being secured about said head portion thereby holding said brackets thereto.