US3908995A

US3908995A - Yoke for game racket

Info

Publication number: US3908995A
Application number: US264820A
Authority: US
Inventors: William E Portz
Original assignee: True Temper Corp
Current assignee: Emhart Industries Inc
Priority date: 1972-06-21
Filing date: 1972-06-21
Publication date: 1975-09-30
Anticipated expiration: 1992-09-30

Abstract

There is disclosed herein a tennis racket comprising a frame member to provide a racket loop, a throat comprising convergent portions at one end of the loop, and a handle. Yoke means are provided across the throat to close the loop, said yoke means being either of single-piece or laminated construction. The yoke means have laterally directed grip portions partially embracing the frame member on either side of the throat, and means for engaging the racket strings.

Description

United States Patent Portz 1 Sept. 30, 1975 [541 YOKE FOR GAME RACKET 3.752.478 8/1973 Flak 273/73 H [75] Inventor: William E. Portz, Geneva, Ohio FOREIGN PATENTS OR APPLICATIONS [73] Assignee: True Temper Corporation, 4,445 2/1903 United Kingdom 273/73 H Cleveland, Ohio 2,010,450 9/1971 Germany 273/73 D 736,167 9/1932 France..... 273/73 G [22] Filed: June 21, 1972 1,578,059 8/1969 France 273/73 G 224,724 11 1924 U 't d K' d 273 73 H 21 Appl. NO.2 264,820 m 6 mg Primary ExaminerRichard J. Ap1ey {52] US. Cl 273/73 G; 273/73 D [51] Int. CL' A63B 49/02; A63B 49/12 58 Field of Search... 273/73 R, 73 c, 73 D, 73 o, [571 ABSTRACT 273/73 H There is disclosed herein a tennis racket comprising a frame member to provide a racket loop, a throat coml l References Cited prising convergent portions at one end of the loop, UNITED STATES PATENTS and a handle. Yoke means are provided across the 1,524,826 2/1925 lcke et a1. 273/73 H throat close the 199p Said yoke means being either 1 1g 727 3/1927 Reach 2 3 H of single-piece or laminated construction. The yoke 1,937,787 12/1933 Robinson... 273/73 H means have laterally directed grip portions partially 1,942,479 l/1934 Kleinman 273/73 G embracing the frame member on either side of the 2,171,223 ROblIlSOl'l H throat and means for engaging the racket strings 3.642283 2/1912 Wilkens 273/73 G 3,724,850 4/1973 Stevens 273/73 G X 9 C1aims, 20 Drawing Figures US. Patent Sept. 30,1975 Sheet 1 of 4 3,908,995

US. Patent 9 Sept. 30,1975 Sheet 2 Of4 3,908,995

US. Patent Sept. 30,1975 Sheet 3 of4 3,908,995

U.S. Patnt Sept. 30,1975 Sheet4 01-4 3,908,995

YOKE FOR GAME RACKET This invention refers to game rackets of the type used in tennis and badminton and particularly to a yoke or bridge adapted to be disposed at the throat of the racket.

Rackets of the type referred to which provide a network of highly tensioned strings as a striking surface are commonly constructed by shaping an elongated framing member in a single plane in such manner as to provide an oval-shaped loop with portions of the elongated member converging adjacent to one end of the loop to provide a throat, the end portions of the member coming together in a substantially parallel manner to provide a handle. This type of construction leaves one end of the striking loop open whereby the same ordinarily must be closed by a yoke or bridge. The yoke commonly comprises a separate length of the same material of which the rest of the frame is made. In other instances, an especially formed and fitted yoke member is inserted into the throat. Whatever form the yoke takes, its purpose is to close and strengthen the loop and provide some means at the throat or the open end of the loop for securing the ends of string running parallel with one dimension of the loop.

The present invention is adapted for use in a game racket constructed in the above described manner and is particularly adapted for use in a racket frame of metallic tubular construction although it is not necessarily limited thereto. The game racket of the present invention comprises an elongated member shaped to form a loop converging into a throat, a yoke being disposed across the throat whereby the loop is closed. The yoke engages said elongated member across said throat and has channel shaped gripping portions at either end overlapping and embracing a portion of the elongated member. String mounting means are carried by the elongated member and the yoke at the inner periphery of the loop by means of which strings means are tightly strung across said loop.

An object of this invention is to provide a game racket of the type set forth above having an improved yoke construction.

Another object of the invention is to provide an improved yoke construction for use in a game racket.

A still further object of this invention is to provide, in a game racket of the type set forth above, means for firmly detachably securing and closing the loop of the racket at the throat.

A further object of this invention is to provide an improved yoke construction which overlaps and embraces portions of the racket across the throat of the racket.

A still further object of this invention is to provide an improved yoke construction of the above type which effectively closes the racket loop between the frame overlapping portions and securely mounts certain of the racket strings.

Still another object of this invention is to provide a yoke construction which can be readily detached and r'emounted to a game racket frame.

Yet another object of this invention is to provide, in a racket having individual string guide units, means for quickly and easily removing and replacing worn or broken units.

Yet another object of this invention is to provide a game racket yoke as set forth above which is simple and sturdy in construction and highly durable in use.

Other objects of the inventionand the advantages thereof will become readily apparent from the following description of one embodiment of the invention shown in the accompanying drawings, in which said drawings:

FIG. 1 is a front elevation of a game racket incorporating one embodiment of the yoke of this invention;

FIG. 2 is an enlarged outside plan view of a cover plate of the yoke of FIG. 1;

FIG. 3 is an inside plan view of the cover plate of FIG. 2;

FIG. 4 is an enlarged plan view of a centerpiece of the yoke as seen from either side thereof;

FIG. 5 is a section taken generally along the line 5-5 of FIG. 1 and greatly enlarged thereover;

FIG. 6 is a section taken along the line 66 of FIG. 1 and greatly enlarged thereover;

FIG. 7 is a side elevation on an enlarged scale of a string guide insert;

FIG. 8 is an enlarged detail of the yoke of FIG. 1, portions being broken away or shown in section for greater clarity;

FIG. 9 is a view similar to FIG. 8 showing another embodiment of the yoke of this invention; 1

FIG. 10 is a top plan view of a yoke section comprising one-half of the yoke of FIG. 9;

FIG. 11 is a detail plan view of a string guide insert shown in assembly with the yoke in FIG. 9;

FIG. 12 is a cross section taken along the line 12'-12 of FIG. 9;

FIG. 13 is a view similar to FIGS.8 and 9 showing still another embodiment of the yoke of this invention;

FIG. 14 is a top plan view of the yoke of FIG. 13;

FIG. 15 is a cross section taken along the line 15+l5 of FIG. 13;

FIG. 16 is a cross section taken along the line 1616 of FIG. 13;

FIG. 17 is a view similar to FIGS. 8, 9, and 13 showing yet another embodiment of the yoke of this invention;

- FIG. 18 is a cross section taken along the line l818 of FIG. 17;

FIG. 19 is a top plan view of the yoke of FIG. 17;'and

FIG. 20 is a cross section taken along the line 20-20 of FIG. 17.

Referring now to the drawings in all of which like parts are designated by like reference numerals, FIG. 1 shows a tennis racket generally indicated by the numeral 10 formed of a single length of metal tube and comprising a loop 1 1, a convergent throat 12, and parallel shank portions 13 constituting a handle. The extreme distal end portion of the handle is preferably encased in a suitable hand grip portion 14 which may be of any suitable type and constitutes no part of the present invention.

Referring now particularly to FIGS. 5 and 6, the tubular framing as herein disclosed is generally rectangular in cross.section having a smooth outer wall 17, inwardly slightly converging side walls 18,'and an inner wall 19 formed to providea continuous, inwardly expended, dovetail shaped channel 20 defined by a recessed bottom wall portion and inwardly converging recessed side wall portions 19b which are integral and continuous with the inner wall 19. As illustrated,

each wall portion curves gently into the adjacent wall portion. The recess may be provided atthe inside periphery of the racket loop 11 as in the firstembodh ment of the invention(FIGS..1-8) or said recess may be at the outside periphery as in the remaining embodimentstFIGS. 920).

In the first embodiment, the dovetail recess 20 affordsmeans for mounting string guide inserts 23 each of which has a base 24, the major portion of which is dovetail shaped in cross section whereby the same can be inserted into the recess 20 and slid to any selected position around the loop 11. Each string guide insert is preferably made from a sturdy plastic and includes an eyelet portion 25 which extends beyond the recess 20 inwardly of the loop 11 and is connected to said base 24 by a narrow neck portion 26. Each base 24 is provided with flat extensions 27 adapted to be disposed in i and project parallel with the recess 20 and serve as a spacer means between said insert anda next adjacent insert. The flat extensions 27 'are adapted to. be trimmed to variouslengths or eliminated altogether if necessary on one side or the other whereby to attain correct spacing of the inserts around the loop 11. Each eyelet portion 25 has an aperture 28 projecting all the way therethrough in a direction parallel with the recess 20 whereby all 'of said apertures are spaced just inwardly of the inner wall 19 of the loop ll. As shown in the side elevation of FIG. 7, the upper edges or corners of the insert 23 may be rounded as indicated at, 29.

From the foregoing, it will be readily appreciated that any suitable number of string guide inserts 23 may be provided in the loop 11 by sliding the same endwise throughthe dovetail shaped channel 20 which will re-' tain them in said loop 11. It will further be appreciated that'said inserts 23 can be spaced closer together or further apart around the curvature of the loop to afford the desired geometric string pattern and that this spacing can be readily determined and maintained ;by varying the sizes of the flat extensions 27 of the insert bases Bridging the throat 12, thereby closing and completing the loop 11 at its lower end, is a yoke 30. As herein described, said yoke comprises a pair of identical metallic cover plates 31 and a centerpiece or spacer 32..

Each cover plate 31 comprises a flatibody portion 33 having an upper arcuate edge 34 so shaped asto close the open end of the loop 11. The outer surface of the body portion 33 may be beveled at the upper and lower edges thereof if desired as indicated at 33a and 33b, respectively.

The body portion 33 is provided with a pair of symmetrically laterally spaced apertures 35 so spaced as to be exactly aligned with like apertures of an oppositely facing cover plate. Said body portion 33 also has a pair of apertures 36 which are countersunk as indicated at 36a and which are lateraliy offset, each being disposed laterally of one of the symmetrical apertures 35,, in the same direction. The body portion 33 is also provided with a pair of tapped holes 37 which are laterally offset in the opposite direction with respect to symmetrical apertures, 35. The spacing is such that one aperture 36 is disposed symmetrically with one of the tapped holes 37 and the other aperture 36 is disposed symmetrically with respect to the other tapped hole 37. Thus it will be readily seen that when a pair of cover plates 31 are disposed with their inner, like surfaces facing each other, a screw placed through an aperture 36 will be aligned and 53 corresponding in position to the pairs of aperr tures 36 and the pair of tapered holes 37,respectively,. whereby screws 54' can pass therethrough when secur with and can be screwed into one of the tapped holes 37.

Referring now particularly to FIG. 3 showing the inner surface of a cover plate 31, said cover plate is provided adjacent to the upper edge 34 thereof with a recess 40 having a flat bottom surface 41 and inwardly and upwardly'inclined surfaces 42. Each recess 40 provides, in effect, one-half of a generally dovetail, shaped channel 43 formed adjacent to the upper edges 34 when a pair of said cover plates are secured together throat 12. As shown in FIG. 5, the flanges45 are so shaped as to form a channel which fits exactly over. the side walls 18 and Portions of the outer and inner walls I 17 and 19 of the framing whereby the yoke 30 is securely attached to the racket frame and the throat 12 is firmly maintained against widening or other distortions.

The centerpiece 32 comprises a central body portion 47 which is flat and has a major portion of its upper arcuate edge recessed downwardly as indicated at .49 whereby it is disposed slightly below the recesses 40 of the cover plate 31. A pair of upwardly converging tabs 50 are provided at either end of said recessed. upper edge 49.

The body portion 47 is provided with a first pair of symmetrically arranged apertures 51 adapted to align with the apertures 35 of the cover plate 31. Said body portion 47-also has asymmetric pairs of apertures 52 ing a pair of coverplates, 31 together (FIG. 5).

The laterally directed ends of the body portion 47 of the centerpiece 32 are provided with slightly arcuate thickened portions. .55 each having an aperture 56 therein. As shown in FIG. 5, the thickened portions are adapted to seat in the dovetail shaped channel 20 of the frame andare secured in place by pins 57 which project through the apertures 56 and suitable apertures 58 in the tubing wali. The grip portions. 44 of the cover plates 31 overlie the ends of the pins 57 thus retaining them in position; With said cover plates secured together by the screws 54 on either side of the center? piece 32, thedovetail shaped channel 43 is thus formed.

whereby the same will retain a plurality of the string guide inserts23. As shown in FIG. 8, in the embodiment herein illustrated, the right-hand string guide insert 23 has had most of the right-hand flat extension 27 removed whereby the same abuts closely adjacentto the right-handtab 50 to maintain its desired position. The tabs 50 retain the string guide inserts 23 of the yoke 30 against endwise movement withinthe groove 43..

In the embodiment of FIGS. 9-12, there is disclosed a two-piece yoke '60. comprising a pair of complemen tary yoke sections 61, one said section being shown in FIG. 10. The sections 61 are identical and are so formed that a pair of them can be placed or assembled at the throat of the racket frame from the front and back thereof, respectively, to grip the frame member and complete the racket loop Each yoke .section 61 comprises an uppermost, arcuate bridge 62 connecting the upper end of a pair of grip portions 63 having offset and laterally projecting flanges 64 defining channels and adapted tooverlap the front .or rear of the racket frame member portions comprising the throat 12. The lower ends of said grip portions 63 are also suitably integrally connected by web means 65.

As best seen in the top plan view ofFIG. 10, each arcuate bridge 62 is provided with a plurality of semicircular grooves 66 so arranged that when two yoke sections 61 are assembled with their inner faces in contact, said grooves 66 form a plurality ofbridge' apertures 67. To align the yoke sections 61, each said yoke section is provided with an inwardly projecting locating pin 68 adjacent to one end of'the arcuate bridge 62 and a pin receiving bore 69 adjacent to the opposite end of said bridge. Thus, when a pair of yoke sections-61 are disposed with their inner faces toward each other to form the bridge apertures 67, each pin 68 in the bore 69 of the opposite yoke section exactly aligns the two sections to form the yoke 60. Said yoke 60 may be secured to the racket frame by any suitable means such as rivets 70 which project through the flanges 64 and the frame portions forming the throat 12. The yoke sections 61 are preferably fastened together at the bridge'62 by a plurality of fasteners 76 which may comprise screws, rivets, or the like.

The arcuate bridges 62 as herein disclosed in this embodiment are particularly adapted for the mounting of a string guide insert 71 (FIG. 11) made of aflexible cushioning material such as plastic or the like. Said string guide insert comprises a plurality of tubular guides 72 connected at like ends by alternately arcuate strip portions 73 and straight stripport'ions 74. Between every other adjacent pair of the bridge apertures 67, the arcuate bridges 62 are provided with arcuate protuberances 75 adapted to nestingly receive the arcuate strip portions 73 when the tubular guides 72 are projected inwardly of the racket loop through the bridge apertures 67, as shown in FIG. 9. The tubular guides 72 preferably project inwardly slightly beyond the arcuate bridges 62 whereby to protect strings from the edges of the bridge apertures 67. As shown, the strings are inserted through one of the tubular guides 72, disposed around aligned protuberances .75 and a strip portion 73 and returned through the next adjacent of said tubular guides. It will be understood that the arcuate strip portions 73 do not need to be arcuate in form provided they have sufficient length to wrap around the protuberances 75.

The form of the invention as shown in FIGS. 9-12 provides the advantage that the bridge apertures can be preformed when the yoke sections 61 are, for example, molded thereby eliminating a drilling operation. It will be further understood in connection with the last mentioned embodiment that the racket frame member can be of ungrooved and nontubular form or can be of the same shape as that shown in the first embodiment and that the strings may be mounted to the remainder of the racket loop in any suitable manner.

Referring now to the embodiment shown in FIGS. l316, a one-piece yoke 80 is shown. said yoke comprising a pair of laterally facing, arcuate grip portions 81 each having a pair of parallel, laterally directed flanges 82 defining a channel and adapted to overlap the front and rear side of the racket frame member at the yoke 12. The upper ends of said grip portions 81 are connected by an arcuate bridge 83 and the lower ends of said grip portionsare connected by an attractive web 84. The arcuate bridge 83 is provided with a plurality of string apertures 85- by means of which stringscan be mountedor secured to the lower end of the racket loop. As herein disclosed, the arcuate bridge 83 is of uniform cross section throughout its length and the same may beprovided with-a suitable string guide insert to protect'the strings against abrasion at the edges of the apertures 85'ifdesired. V The-one-piece yoke" *is suitablysecured to th frame of the racket by any suitable means'such as rivets the flanges 82 and the racket arcuate bridge 93 in "the same manner as the apertures are provided in the arcuate bridge'83.

Means for securing the yoke to the throat of the racket comprise a plurality of cap screws 96 which project inwardly through thebottom wall portion 19a of an outwardly opening recess 20 and through thewall' 17', which is this form of the inve'ntion comprises an inner wall'of the racketfra'me. The wall portion 19a is provided with an enlarged opening 99 large enough to countersink the cap screw headfAn upper pair of said cap screws 96 project into thickened end portions97 of the bridge 93 and a lower pair thereof are threaded into a thickened reinforcementportion 98 of the web 94. i i

From the, foregoingit will be readily seen that the present invention provides improved yoke means for a game racket which rigidly secures the frame members across the racket throat and effectively closes and completes the racket loop. In the case of the first embodi-j ment, an'improved laminated yoke is pro vided which is 'readilydetachable for quickly and easily removing and replacing worn or broken string guide inserts at the time of restringi ng. The second embodiment of the invention provides an even simplier means for quickly replacing the string guide inserts at the yoke at the time of restringing the racket. All of the embodiments provide a yoke that firmly grips the racket at the curved portion of the throat by providing channel shaped grip portions overlapping the racket framing member and being so secured thereto as to give the frame and loop great rigidity and impact strength.

It will be understood that many changes in the details of the invention as herein described and illustrated may be made without, however, departing from the spirit thereof or the scope of the appended claims.

I claim:

1. A game racket comprising an elongated frame member formed into a loop and having converging portions forming a throat and handle portions extending beyond said throat; said racket having a longitudinal axis; a yoke disposed parallel with the plane of said loop and connecting said converging portions of said elongated frame member across said throat;said converging portions having inner surfaces directed toward said axis, outer surfaces directed away from said axis, and substantially parallel front and rear side surfaces; said yoke having on each lateral side an oppositely facing, converging grip portion which is wider than said converging portions in arfront to rear direction and,

comprises a bottom wall and outwardly directed substantially parallel flangesdefining a channel shaped to substantially conform to the inner surfaces of said converging portions of said frame member, said inner surfaces, of said converging portions nesting within said channelsbetween flanges and on said bottom wall and said flanges surrounding substantial portions only of said front and rear sides of said converging portions of said frame member; means securing said channels to said converging portions of the frame member; said yoke also having a bridge means connecting said grip portions to each other across said throat, said bridge means including (a) string mounting means disposed along the lateral edge of the bridge means facing inwardly of said loop, and (b) a rigid body portion disposed on the outward side of said string mounting means away from said loop.

2.A game racket as set forth in claim 1 wherein said means securing said channel to said convergingportion comprises fastening means extending through said converging portion of said frame member and anchored to said bottom walls of said grip portions.

3. A game racket as set forthv in claim 2 wherein said rigid body portion of the bridge meansof said yoke is integrally joined with said grip portions and comprises a relatively thin web portion spaced from said string mounting means; at least one edge of said web having 1 securing each of said channels to its corresponding,

tending between said grip portions; said bridge means and said enlarged reinforcement having end portions of sufficient thickness to receive said securing means; and said securing means comprises fastening means projecting through said converging portions of said frame converging portion of said frame member comprises fastening means extending throughsaid outwardly extending flanges and said converging portion of the frame member.

5. A game racketas set forth in claim 1 wherein said vergent ends of said grip portions; at least one edge of I said web having an integral enlarged reinforcement exmember and said bottom walls and extending into the ends of said bridge means and the ends of said enlarged reinforcement.

6. A game racket as set forth in claim 1 said yoke comprising a pair of complementary yoke sections each comprising one-half of said string mounting means, body, portion and grip portions and being divided along a central plane paralleliwith the plane of said loop portion and having an inner surface facing the other section; each said half of said string mounting means having grooves on its inner surface aligned with the grooves of the othersection whereby upon assembly of two said yoke sections to said throat, aperturesare provided in said string mounting means for mounting strings to said game racket.

7. A game racket as setforth in claim 6 each said half a of said string mounting means having semicircular protuberances between alternate adjacent pairs of said grooves projecting outwardly of said racket, loop whereby semicircular protuberances are provided between alternate adjacent pairs of said apertures of said string mounting means; a flexible string insert guide means in strip form comprising a plurality of tubular guides inserted in said apertures, said tubular guides,

being connected by integral strip portions, alternate of said strip portions curving around said semicircular protuberances.

8. A game racket as set forth in claim 6 said means securing said channels to said converging portions comprising rivets projecting through both flanges of each said grip portion and said converging portions.

9. A game racket as set forth in claim 1 said string mounting means having through apertures therein the ends of which open inwardly and outwardly of said loop; said string mounting means having semicircular protuberances disposed between alternate adjacent pairs of said apertures projecting outwardly of said racket loop; a flexible string insert guide means in strip form comprising a plurality of tubular guides inserted in said apertures, said tubular guides being connected t by integral strip portions, alternate of said strip por tions curving around said, semicircular protuberances.

Claims

1. A game racket comprising an elongated frame member formed into a loop and having converging portions forming a throat and handle portions extending beyond said throat; said racket having a longitudinal axis; a yoke disposed parallel with the plane of said loop and connecting said converging portions of said elongated frame member across said throat; said converging portions having inner surfaces directed toward said axis, outer surfaces directed away from said axis, and substantially parallel front and rear side surfaces; said yoke having on each lateral side an oppositely facing, converging grip portion which is wider than said converging portions in a front to rear direction and comprises a bottom wall and outwardly directed substantially parallel flanges defining a channel shaped to substantially conform to the inner surfaces of said converging portions of said frame member, said inner surfaces of said converging portions nesting within said channels between flanges and on said bottom wall and said flanges surrounding substantial portions only of said front and rear sides of said converging portions of said frame member; means securing said channels to said converging portions of the frame member; said yoke also having a bridge means connecting said grip portions to each other across said throat, said bridge means including (a) string mounting means disposed along the lateral edge of the bridge means facing inwardly of said loop, and (b) a rigid body portion disposed on the outward side of said string mounting means away from said loop.

2. A game racket as set forth in claim 1 wherein said means securing said channel to said converging portion comprises fastening means extending through said converging portion of said frame member and anchored to said bottom walls of said grip portions.

3. A game racket as set forth in claim 2 wherein said rigid body portion of the bridge means of said yoke is integrally joined with said grip portions and comprises a relatively thin web portion spaced from said string mounting means; at least one edge of said web having an integral, enlarged reinforcement portion extending between said grip portions.

4. A game racket as set forth in claim 1 said means securing each of said channels to its corresponding converging portion of said frame member comprises fastening means extending through said outwardly extending flanges and said converging portion of the frame member.

5. A game racket as set forth in claim 1 wherein said grip portions and bridge means are integrally formed; said body portion comprising a relatively thin web spaced from said bridge means and connecting the convergent ends of said grip portions; at least one edge of said web having an integral enlarged reinforcement extending between said grip portions; said bridge means and said enlarged reinforcement having end portions of sufficient thickness to recEive said securing means; and said securing means comprises fastening means projecting through said converging portions of said frame member and said bottom walls and extending into the ends of said bridge means and the ends of said enlarged reinforcement.

6. A game racket as set forth in claim 1 said yoke comprising a pair of complementary yoke sections each comprising one-half of said string mounting means, body portion and grip portions and being divided along a central plane parallel with the plane of said loop portion and having an inner surface facing the other section; each said half of said string mounting means having grooves on its inner surface aligned with the grooves of the other section whereby upon assembly of two said yoke sections to said throat, apertures are provided in said string mounting means for mounting strings to said game racket.

7. A game racket as set forth in claim 6 each said half of said string mounting means having semicircular protuberances between alternate adjacent pairs of said grooves projecting outwardly of said racket loop whereby semicircular protuberances are provided between alternate adjacent pairs of said apertures of said string mounting means; a flexible string insert guide means in strip form comprising a plurality of tubular guides inserted in said apertures, said tubular guides being connected by integral strip portions, alternate of said strip portions curving around said semicircular protuberances.

9. A game racket as set forth in claim 1 said string mounting means having through apertures therein the ends of which open inwardly and outwardly of said loop; said string mounting means having semicircular protuberances disposed between alternate adjacent pairs of said apertures projecting outwardly of said racket loop; a flexible string insert guide means in strip form comprising a plurality of tubular guides inserted in said apertures, said tubular guides being connected by integral strip portions, alternate of said strip portions curving around said semicircular protuberances.