US1831413A - Tennis racket - Google Patents

Description

H. W. HALL TENNIS RAGKET Nov. 1o, 1931.

Filed June 12, 1950 2 Sheets-$11661 l H, W. HALL TENNIS RACKET Nov. 10, 1931.

Filed June l2, 1930 2 Sheets-Sheet 2 Patented Nov. 10, 1931 HORACE W. HALL, OF NEWTON, MASSACHUSETTS TENNIS Application led .Tune 12,

This invention relates to tennis rackets, and more particularly to means for strengthening certain portions thereof.

After a racket has been played with, itA often shows a weakness at the base of the throat. This is true of rackets which have been steamed and bent to bow shape because of the internal strain the wood is under, and it is also true of rackets which have an open throat. The stress and strain of severe play tends to loosen the glued joint at the base of the throat where the two handle portions of the bow arev joined together, either directly, or where the said two handle portions are oined to a center piece, in which latter event there are two joints to loosen. To prevent this loosening or Spreading of the joints various remedies have been tried. A screw has been inserted into the handle at the base of the throat; but it has not been successful in preventing this. Tape, iiberloid and other flexible materials have been wrapped around the handle lto overcome this tendency to spread; but without lasting effect. Material `which is flexible enough to wrap around the handle does not serve the purpose.

One of the objects of my inventionis to provide a reinforcement which will effec-- tually prevent any loosening of the joints at or near the base of the throat, which will be economical to manufacture, simple to applyl .to the racket and not detract from its appearance. I have 'accomplished these objects by placing a reinforcing plate of wood at the base of the throat, the grain running across the handle. The strength of the cross grain permanently overcomes the loosening or spreading of the joints, which spreadin has been in the longitudinal direction o the handle.

Another weakness in the above-mentioned rackets lies in the joints between the outer sides of the throat and the throat portions of the bow which tend to loosen or spread f when the racket is subjected to severe play.

Inasmuch as I have found it preferable to provide a strong center piece for my throat which extends from the handle portion up to and forms part of the throat, such construction has enabled me to use two separate RACKET 1930. Serial No. 460,591.

pieces to strengthen the racket at the shoulders and definitely prevent any spread taking place at the joints between said sides of the throat and the bow. I` accomplish this n with the minimum amount of labor and with relatively slight waste of material and yet secureA the strength inherent in the cross grains of'wood used, by having each of my shoulder reinforcements extend from a curved portion of the bow head to said cen' ter piece, preferably on both faces of the racket.

It has been the practice for many years to strengthen the lower inside portion of the bow head by steaming and bending a piece of wood, such as ash, and fitting it under pressure so lthat it closely adheres to the inside surface of the bow head and throat, extending from one side of the bowhead to the other. Inasmuch as this piece of wood cannot be bent into a shape which makes an exact iit 'when it is steamed and bent, and after drying the fibres in the wood are permanently set, it takes a great deal of pressure to make this crescent shaped reinforcing strip closely fit the' inside of the bow portion and throat. There is a natural tendency for said piece to resume-the shape it assumed after being steamed and bent, which means that it tends to pull away fromthe bow head and throat. This occurs especially when Stringing, asA the longitudinal strings are first inserted in the racket and tightened, by pulling downwardly. The tightening of said longitudinal strings puts a severe strain upon the glue joints of this crescent shaped sov reinforcement piece tending to separate said piece. from the throat and bow portion to which it is attached. This occurs especially often at the second Stringing and renders this reinforcing` piece useless.` It has been my object to overcome this tendency'to loosen and break vsaid joint by reinforcing this portion of the racket with th'in laminations especially arranged that can be bent without steaming, instead of using a single piece of thicker wood, which requires preliminary steaming and bending and drying before insertion, thereby not only greatly strengthclaims.

In the drawings: Figure 1 is a front elevation of a racket yembodying my improvements with a. small portion broken away. r

Figure 2 is a perspective view of the reinforcing plate used at the base of the open throat.

Figure 3 is a cross section -on line 3-3 of Figure 1 showing the application of my reinforcing plates on both facesof the racket.

Figure 4 is a perspective view of a piece 'of wood from which one of the shoulder reinforcement pieces is sawed out, which piece is shown at Figure 5.

Figure 6 is a cross section on line 6`6 of Figure 1 showing shoulder reinforcement pieces, and laminations for strengthening the throat and part of the bow head at the inner surface thereof.

Figure 7 is a front fragmentary view to illustrate the laminations on the inside of the bowhead to strengthen the throat and a portion of the bow head.

Figure 8 is a cross section on line 8-8 of Figure 7.

Figure 9 is a perspective view showing the three individual laminations before they are applied to the racket.

In referring Ato the bow of the racket the whole outer Vframe of the racket is meant including the upper or curved portion known as the head, and the lower or handle portion. The shoulders are the two side portions of I the head just above the' throat.

As illustrated in Figures 1 and 7 of the drawings, a throat is shown which consists of two side sections 11 and a center piece 15. This centerA piece 15 is made of strong,

- heavy, tough wood, such as maple or birch,

and runs from the handle portion 13 of the bow up into the throat, forming a part thereof. The side sections 11, which are made of lighter wood than said center piece, do not extend down to the base of the throat, where i said handle portion 13 begins, thereby leaving open spaces 12 on each side of said center piece 15, so that the throat is partly open.

The two sides 14 of the bow, which extend from the top of the head to the base of the handle 13, are shown joined to said center piece 15 at the base of said throat. I have found it preferable to use a center piece, although the two bow sides 14 Vcould be joined directly together thereby forming but one joint. The joints 16, which are thus formed at the base of the throat, tend to open or spread approximately where the handle portion 13 commences, when the racket is subjected to hard play, thereby spoiling its appearance, and the split gradually extends down into the handle until the racket is seriable in atleast one direction, such as bakeli'te or fiber, may be used. This plate must be sufficiently thick to prevent separation of the bow sides 14 from'each other or from the center piece l5 when lone is used. I have found that wood less than fg thick is suitable. This reinforcing plate 17 is glued or otherwise united to the two sides 14 of the bow at approximately the base of the throat, extending across the face of the handle portion 13, there being'one on the front face and another on the back face of the racket as clearly shown in Figure 3. Any suitable wood of suiicient strength may be used, such as birch, mahogany or black walnut, and the grain should run at substantially right angles to the longitudinal axis of the handle. In the finished racket` this plate 17 is tapered down and smoothed off evenly.

Inasmuch as thereis considerable strain on the racket at the shoulders it has beenfound desirable to lreinforce the shoulders on both faces of thelracket, especially when the bow is under considerable internal strain, I

as in ash bows, which have been steamed and bent to the desired shape, and also when the throat is open. The joint 20, formed by the of said throat and shoulder portions, necessitating a sharp bend in the wood. This kind of reinforcement is expensive and the correct shape is difficult to obtain. By using a center piece 15, which extends from the handle 13 to, and forms part of, the throat, I provide the necessary strength at the center, and the shoulders and throat can bereinforced up to, but preferably not covering the center piece 15, by using two Separate pieces of wood, eliminating the necessity of making a sharp bend, as when one piece alone is used. These shoulder reinforcing pieces 22 are shown in Figure 1, extending from a point less than half way up the-head portion of the bow to a point in alinement with the outside edge of said center piece 15, leaving a space 23 between the lower ends of said two reinforcing pieces 22, through which space said center piece 15 may be seen.

In thus showing the center piece 15 locked into the throat it is apparent to even the layman that this center piece must greatly strengthen the racket; whereas if there were no space 23 between the reinforcing pieces 22 the center piece would appear to end at the base of the reinforcing pieces 22, and that portion which is locked in would not be visible. As tennis rackets are commonly provided with a crescent shaped reinforcing piece superimposed upon the inside surface of Ethe lower portion of the bow head and across the top of the throat, which greatly strengthens the racket, this crescent piece provides a cross banding for the center piece 15, safeguarding the joints between said center piece 15 and side sections 11 from any tendency to loosen.

Thus reinforcing the shoulders with two pieces 22 not only cross bands. the joints 20, but gives a wider choice of woods, making it possible to use lthehandsomer cabinet woods such as mahogany or black walnut, the fibres of which are too short to permit steaming and bending sufficiently to make the sharp bend necessary when only one piece is used to reinforce both shoulders. Having a." greater choice of woods also makes possible a color `synchronization with the different woods used in other portions of the racket. These pieces 22 may be sawed out of a comparatively small piece of wood as shown 1n Figure 4, or.

they may be bent to the desired shape, the bending being possible with the cabinet woods because the' curve is so slight. 1f these reinforcing pieces 22 are sawed out the cross grain effect is not lost, whereas if a single piece extending from shoulder to shoulder were sawed out it would be of-insuiicient .strength because the grain of certain portions would run nearly parallel with one of the glue joints 20, rendering it useless as a reinforcement for this joint.

In place of the single crescent shaped piece of wood, usually ash. superimposed upon the inside surface 24 of the lower curved portion of the bow head, and extending from one shoulder, across the throat, to the other shoulder, I use laminations 25, preferably three in number. The lowest one 25a extends from approximately half way up;l the head of the bow on one side down across the throat and up the opposite side of said head, as shown in Figures 1 and 7 of the drawings. Another shorter lamination 25?) is superimposed upon 25a, which preferably does not extend so far up the bow head, and a preferably still shorter lamination 250 is superimposed upon 25?). It is desirable to taper these laminations at 'their ends so that they may appear to almost dovetail into the sides 14 of the bow. These laminations 25 are preferably formed from sheets of thin veneer of approximately l thickness. They are thin enough to bend easily to the desired shape without steaming and when in place are under practically no internal strain. It has been proven that a piece composed of a plurality of laminations bound together with a glue stronger than the wood is considerably stronger than a single piece ofthe same wood equal in thickness to the combined laminations and glue. As heretofore explained there is a terrific downward strain on the head of the bowwhen the longitudinal strings are tightened in Stringing, tending to separatethe crescent shaped piece from the bow head and throat. By running my lowest lamination 25a half way up the bow this lamination ytakes up part of the strain as it begins to take effect on the lower half of the head, and as the strain passes Forming this inner crescent shaped piece of laminations also simplifies the construction of this portion of the racket for steaming of wood is entirely done away with. A wide sheet of thin veneer is preferably used, sawing or cutting it into pieces preferably as wide as the bow head portion to be covered.

Waterproof glue is applied to the surface of the throat and inside surface of partof the bow head and to the under surface of the lamination 25a and said lamination is placed upon and easily bent to conform to the shape of said inner surface. The to-p surface'of 25a and the under surface of 25o are glued and 25?; superimposed on'25a and this is followed by superimposing 250 on 25o, the top surface of 25?) and under surface of 250 being also glued. Pressure is then applied and when the glue'has set the united laminations 25r have become a permanent part of the racket and it is practically impossible to break the glue joints. i v Likewise wide sheets of veneer can be use for the three-ply crescent reinforcement in connection with my multiple racket production method as revealed in my Patent No. 1,682.504. This" type of reinforcement is especially good for said multiple production method because it allows greater ease in holding when assembling and the cost per racket lll for gluing and pressing is much less. It is i impractical, however, to make the usual single crescent reinforcement piece with a multiple production method, such as revealed in said patent, before the block is sawed up to make the individual racket.

These laminations are tapered at the ends, and as no steaming is required, a wide choice of woods is available, so that a color harmony with the rest of the racket is easily obtained and the general appearance of the racket is enhanced. The binding cords 26 shown bound around different portions of the bow are merely for ornamentation purposes.

What I claim is: v

l. A racket comprising a center piece extending from the handle portion to and being locked into the throat, and shoulder re? inforcing pieces each extending from a point substantially in alinement 'with an outside l and part way up the head of the racket.

2. A racket comprising a center piece exl tending from the handle portion up .into the throat, and shoulder reinforcing pieces on each side of said center piece each extending center piece to the shoulder portions of the bow, whereby said center piece is visible in the space between the lower ends of said shoulder pieces.

3. A racketfthe throat portion of which embodies a center piece and two side sections, comprising shoulder reinforcing pieces superimposed upon the opposite faces of the racket shoulders and said side sections, each of said reinforcing pieces being of such width as to cover its shoulder and side section and terminating at its lower end ata point substantially in longitudinal alinement with one of the joints formed at the union of said side sections and said center piece.

4; A racket having an open throat and comprising two small reinforcing plates of wood on opposite faces of said racket which are between the open throat and the handle of the racket and said plates being located at approximately the base of said open throat with the grain of each running across the handle.

5. A racket having an open throat and comprising two polygonal reinforcing plates of wood on opposite faces of said racket disposed between the open throat of the' racket andthe handle thereof at approximately the base of said open throat with the grain off said wooden plates running across the racket' handle. c

6. A racket comprising two throat side sections and a longitudinal center piece'between2 said sections extending below the throat into the handle, having an opening in the throat portion on each side of said center piece im'- mediately above the point where said center piece joins said handle, and a small recacross the handle.

tangular wooden Areinforcing plate on each face of said racket superimposed upon said handle at approximately ,the base of s aid openings, the grain of said plates runmng HORACE w. HALL.

l edge of said center piece across the throat ICO

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