US1526734A - Tennis racket - Google Patents

Description

web, 17, 1925. 1,526,734

F. B. ANDREWS ET AL l TENNIS RAGKET Filed April 4, 1925 n @11.1- W111i- W114- wm 1N V E N TORl EM 'SQ/7% ATTORNEY Patented Feb. 17, 1925.

AUNITE-n STATES FREDERICKB. ANDREWS, orJ YonKEn-s, aan` WILLIAM s. IVIILLEP., or

NEW

YORK, N. Y.

TENNIS RACKET.

:Application filed April 4,

To all whom it lm ay concer/n.:

Be it known that we, Fnnnnaioit B. AN- Dnnws and W ILLIAM S. MILLER, citizens of the United States, residing, respectively, in the city of Yonkers, county of Westchester, State of New York, and in the city and county of New York, State of New York, have invented a new and useful Tennis Racket, of. which the following is a specification in such full and clear terms as will enable those skilled in the art to which it appertains to make and use the same.

This invention relates to tennis rackets and has more special reference to a racket in which the stretches of string are 'independent of each other and are individually adjustable to afford a racket in which the y strings may be properly tensioned and easily' replaced. While independent stretches of metallic string tensioned by means'of a regulating screw engaging threads formed directl in the metallic string have been propose nevertheless such arrangements are objectionable as being solely applicable to metallic strings which are not in favor with the playing public, as unduly wearing the balls, expanding and contracting to a marked degree under the influence of tei'nperature changes and having many other objectionable features.

It has also been proposed twisting a pair of the strings to create the necessary tension but such method is objectionable as somewhat shifting the balance of the racket, reducing the life of the string and permanently distorting the twisted portions of the strings and as having all the objections ofl c the conventional method of Stringing in that the breaking of -a string loosens the entire racket.

The present invention affords a construction in which screws are eliminated and hence is not only applicable to metal strings but may be used equally well with the conventional gut Stringing for which as a matter of fact it is more especially designed.

Another phase of the invention resides in providing an adjustable oscillatable member in the racket handle which will vibrate in unison with the strings comprising the racket head and afford a balanced vibra'- tion on each side of the region of the throat iece which is the approximate center of Inertia of the racket.

While yseveral embodiments of the mven- 1923. Serial No. 629,826.

tion are disclosed in the drawing it is to be j understood that these embodiments merely serve as illustrations of the underlying principles of the invention so that they may be readily con'iprehended by those rskilled in the art and are not intended as limiting the invention to the specific foi-m disclosed therein.

Fig. l is a front elevation of a racket with the invention applied thereto.

Fig. 2 is a side elevation of Fig. 1.

Fig. 3 shows one form of the string lock ing mechanism.

Fig. 4 shows another form of the string locking mechanism.

Fig. 5 shows still another form of the string locking mechanism. j

Fig. 6 shows a section of Fig. 5 on the line 6--6.

Fig. 7 shows a perspective view ofthe locking mechanism shown in Fig. 5.

Fig. 8 shows a fragmentary detail. view partly in section of some of the elements shown in Fig. 1. Y

Continuing now by way of a more detailed description the conventional racket A comprises handle B, throat piece C and frame or head D. Instead of utilizing the conventional method of sti-inging in the framed) which in effect consists of weaving a single string backwards and forwards, it is contemplated using an` individual string for each stretch. The customary apertures in the conventional racket frame are slightly enlarged to receive locking mechanism as shown more especially in Figs. 3, 4, and 5. Either one of these locking mechanisms'inay be used although various other equivalent arrangements within the scope of the claims may be substituted. These locking mechanisms are preferably secured to but one end of the individual strings, although of course they may also be secured to each end of the string. In the preferred arrangement with a locking mechanism secured to but one end of the string, the opposite end of the string is knotted and may be countersunk in the frame by providing a suitable recess if desired. In the event that the arrangement just mentioned is utilized, the locking mechanisms are arranged in staggered fashion on opposite sides of the frame resulting in a pair of locking mechanisms with a knotted end between them. The locking mechanism shown in Fig. 3 comprises a flared shell Ef apertured at opposite ends and having a retractile tubular plun rer E coaxially arranged in the shell an having a plurality of apertures F adapted to receive a pluralilty of wedging members specificall balls i which are normally pressed, Witi their associated plunger by spring G toward the constricted end of the shell, the balls being forced toward each other by this constricted end Iand forced into locking position with the string H which passes through one end of the apertured shell and through the tubular plunger E. By retracting the plunger E the balls are disengaged from the string H thereby unlocking the string and permitting it 'to be withdrawn from the plunger E'. The locking mechanism shown in Fig. 4 consists of a hollow cone 5 fitted into a suitable recess formed in the trame and a ball K Which is preferably prevented from fall ing out of the cone by a dependent Hap K or other equivalent means. l H is pulled taut the ball K is rolled into Wedging position and the normal tension of the string and its frictioual engagement with the ball keeps the latter in place as will be readily understood'.`

The construction shown in Figs. 5, G and 7, comprises a. Wedge L, having a longitudinal roove or channel L adapted tov receive tie string H, sufficient clearance being preferably provided so that the string runs freely through the channel,` this clearance obviating the usual loosening of the string when an ordinary wedge is used. In order to lock the string to the frame a dependent flange or tail M is formed with the Wedge and bears on the down-turned end M of the string H.

In Fig. 8 there is shown a construction for producing vibration in handle simultaneously With the vibration in the head. A sleeve P is fitted on the handle B and has one end of a vibratory body specifically a string Q secured at one end. the other end of the string being attached to a slidable block Q cooperating with an adjusting i screw P located at the butt end of the haiidle B. "The adjusting screw affords the After the string means for tuning the string Q so that it will have a definite vibratory period relatively to the period of the strings H.

The center of balance of a tennis racket is located approximately at the th'rat piece Iand when the strings of the head of the racket are struck by a ball the racket tends to rotate above this center of balance. The inertia of the string, causes it to lag behind the handle and hencev is thrown into vibration, the phase of vibration of the string differing from the phase vibration of the strings of the head and offsetting or balancing their vibration to a certain extent.

While various equivalent arrangements are indicated in the specification it is to be understood that these are not the only ones which may be employed but all equivalent arrangements Within the sco e of the appended claims are included Within the scope of the invention.

It is claimed:

1. A tennis racket comprising a frame having a plurality of apertures, a plurality of independent stretches of Stringing lo-y cated in the frame and each of the stretches having their opposite ends projecting through the traine apertures, a shell in the apertures through which the string ends pass, a rectractile plunger located in the shell, the plunger having a. manually operable end and being apertuied to receive a portion of a stretch of Stringing and wedging means controlled by the plunger to wedge the stretches of Stringing to the shell.

2. A string locking device for tennis rackets comprising a tubular shell, a retractile plunger in the shell and Wedging means cooperating Witli both the plunger and the shell to lock with the string.

3. A racket comprising a frame and handle, an opening in the butt end of the handle, a sleeve in the opening, a vibratory string in the sleeve and having one end attached to a portion of the sleeve and th(` other end attached to a slidable block and means to regulate the position of the block.

FREDERICK B. ANDREWS. WILLIAM S. MILLER.

Images