US2015238A - Racket string tightening machine - Google Patents

Description

Sept- 24, 1935- l J. sALADlNo 2,015,23

RACKET STRING TGHTENING MACHINE Filed July 30, 1954 3 Sheets-Sheet l afferra@ J. sALADlNo 2,015,238

RACKET STRING TIGHTENING MACHINE Sept. 24, 1935.

Filed July 50, 1934 3 Sheets-Sheet 2 n law-4. 6 z h j V a 35u/@WM Kaw/2%@ 5 Sept. 24, 1935.

J. SALADINO RACKET STRING TIGHTENING MACHINE Filed July 30, 1934 3 Sheets-Sheet 3 J4 als as 3 57 61 50 6,7

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Patented Sept. 24, 1935v UNITED STATES PATENT OFFIQE RACKET STRING TIGHTENING MACHINE Joseph Saladino, Reading, Mass. Application July 30, 1934, Serial No. 737,562

8 Claims. (Cl. 273-73) This invention relates to a machine adapted to tighten the playing strings of a tennis, squash, badminton or other racket or bat, which are commonly made of wood, liber, steel or aluminum.

At the present time rackets are strung by hand and the tightening or tensioning ofthe strings is accomplished by the operator taking hold of the strings with his hand and repeatedly pulling them, which is diiiicult and straining work. The degree of tightness of the strings in the racket is to a great extent a matter of guesswork now, as the operator can only estimate their tightness by the sound or pitch resulting from strumming them. Inasmuch as the tightness of the stringing is of great importance, especially to skilled players, it has been, for many years, the constant aim of those in the industry to find a way of Stringing rackets to a certain known degree of tightness or tension with all strings alike, which aim is accomplished by my invention.

One object of my invention is to provide a machine which will tighten the playing strings in a racket mechanically thereby doing away with the necessity of pulling them by hand. Another object is to provide such a machine that will determine the degree of tightness of the stringing, so that each string may be tightened to any desired degree, and be uniform with the others. Still another object is to make such a machine simple and speedy in operation and relatively in- A further object is to make such a machine adaptable to various sizes and shapes of rackets.

The foregoing and other objects which will appear as the nature of the invention is bette'rvunderstood, may be accomplished by a construction, combination and operative arrangement of parts such as is disclosed by the drawings. The nature of the invention is such as to render it susceptible i to various changes and modifications, and, therefore, I am not to be limited tov the construction disclosed by the drawings; but am entitled to all such changes therefrom as fall within the scope of my claims.V v

In the drawings:

Figure l is a side elevation view of my racket Stringing machine with a tennis racket held thereby for Stringing longitudinally.

Figure 2 is a section taken on the line 2-2 of Figure 4 illustrating the side clamp of the racket holder holding a racket.

Figure 3 is a section taken on the line 3 3 of Figure 4 showing the pulley, with cable fastened thereto, of the string tightening device.

Figure 4 is a plan View of my racket Stringing machine, the string tightening device being shown in normal position.

Figure 5 is a plan view of my racket Stringing machine with a tennis racket held thereon for Stringing laterally, and showing the string tightemng device in actuated position.

Figure' is a section taken on the line 6 6 of Figure 4, illustrating the mechanism of the string tightening device in detail.

Figure 7 is a section taken on the line l--l of Figure 4 showing details of the pawl and ratchet of the string tightening device.

Figure 8 is a section taken on the line B--i of Figure 5 showing the barrel member of the string 10 tightening device.

Figure 9 is a. plan view of my racket Stringing machine in actuated position, showing an insert holder which is used to accommodate the smaller size rackets.

Figure 10 is a' section taken on the line lil-Iii of Figure 9 showing the clamping means with the racket holder in detail with the insert holder in position thereon.

Figure l1 is a section taken on the line l l-H 20 of Figure 9, the view being similar to Figure 2, illustrating the side clamp of the racket holder with the insert holder in place.

As illustrated my machine has a supporting stand or base l5 having a bossed portion i6 into 25 which a vertical standard l1 nts. Attached to said standard il by screws i9 is a guide bracket I 8, and extending between said bracket i8 and said standard il is a treadle 2| pivoted as at 22 to a yoke 23 which screws into said base i5. Said 30 treadle 2i has a foot lever 25 aiiixed thereto by screws 2S, pressure on which foot lever 25 actuates the string tightening device later described.

Adjustably mounted on said treadle 2i is a block 28. held by a thumb screw 29 in any desired 35 position. An eye member 3i! fits in said block 28 to receive a cable or belt 3i which passes over a pulley, later described, and is fastened at the other end to a spring 52 which in turn is fastened to one of said screws i9 which hold the guide 40 bracket i8.

Said standard Il telescopically engages a vertical sleeve 34, and is held in any desired position by a hand screw 35, so that the height of my machine may be adjusted vertically to the convenience of the operator. Mounted on said sleeve 34 isa tool support or table 35. A bracket 3S is fastened to said sleeve 34 by a set screw 39, and said bracket 38 has an arm or upstanding part All which supports the string tightening device 64 later described.

A holder 42 supports and holds the racket 49, and is rotatable so that the position of said racket may be changed as the Stringing proceeds. For instance, when the longitudinal Stringing is done the racket is held in the position shown in Figure l of the drawings, while the cross Stringing is done with the racket held in the position shown in Figure 5 of the drawings. Said holder 42 consists of a supporting trame 43 which is rotatably 60 mounted on said bracket 38, being rotatable about bearings 44. A cap or plate 45 rests on the bottom of said frame 43 and is held to said bracket 38 by a large screw 48. Said holder 42 has a top 48 which is integral with said frame 43 on which the tennis racket 49 or other playing instrument rests while being strung. The ordinary racket consists of a curved portion known as the bow head, which receives the Stringing, and a straight handle, as illustrated in Figure 5 of the drawings.

To hold said racket 49 in position on said top 43 of said holder 42 there is a hook member or clamp 58 at the rear of said holder 42 which holds the upper head portion of the racket, the hook portion resting on the top face of the racket, being shown at the right in Figure l of the drawings. This hook member 59 is held by a thumb screw 5| which screws into the said frame 43, passing through a long vertical slot 52 in said hook member, which slot makes said Vhook member vertically adjustable so it can be used for rackets of different thickness.

At the lower or throat portion of the head of the racket is a front clamp member 53, which also has a hooked portion 54, which extends above the said top 4S and presses horizontally against said bow head as shown in Figure 1 of the drawings. This clamp member 53 is held by a thumb screw 55 which loosely extends through said member 53 and is threaded into said frame 43, below which is an aligning thumb screw 56 which is threaded into the said clamp member 53, and serves to hold said member 53 straight,

At each side of the said holder 42 are side clamps 57 which hold the racket at each side and which have a hole 59 tapped into them. Said top has projecting portions 58 integral' therewith to thereby provide a long slot 8| so that said clamps 5? may be moved horizontally to make adjustments for rackets of various thickness. A thumb screw 68 passes through said slot 5|, a portion of which bears against the bottom surface of said top 48 when it is tightened, and said screw 98 enters said hole 59 to thereby prevent any horizontal movement of said clamp 51. As illustrated in Figure l0 of the drawings this slot 8| is oversize with respect to said screw 58 so that some sidewise adjustment is possible, in order that the clamp 5l may be axed to the racket in such a way that it will avoid covering any of the stringing holes.

The strings in the racket are pulled tight by a rotatable tensioning or tightening device 94 which has a pulley 55 fastened thereto by screws 56 which extend from a ratchet El into said pulley. Said pulley 65 has a longitudinal hole 62 extending therethrough as illustrated in Figure 3 of the drawings, through which said cable 3| passes, and set screws 93 are tightened directly against said cable 3| in said hole 82, to thereby hold the cable fast, as it is important that there be no slipping of the cable during the tightening operation. Said device 64 has a ratchet 8l a portion of which has teeth 68. A screw 69 extends through a portion of said ratchet Sl into a horizontal shaft 18 which has a cap 1| at one end integral therewith. A helical spring '|2 has one end as at 13 projecting into said cap '5| as best illustrated in Figure 6 of the drawings, the other end I4 passing into a hole in the wall of a barrel 16, which together with said cap encloses said spring l2. A bushing which surrounds a portion of said shaft 10, is made integral with said barrel 'l5 and rotatably ts into a housing 18 which is an integral extension of said bracket arm 40.

An indicator pointer 19 is fastened to said bracket 48, and as said tightening device 64 is rotatably moved a scale 89, marked on the outside of said barrel 16, rotates therewith, and the numeral on said scale 89 which is opposite the pointer 19 shows to what degree the strings 83 in the racket have been tightened. Usually the strings 83 are tightened in terms of pounds, and the scale 8D ordinarily indicates pounds, although it could indicate other terms as well.

A cleat 8| on said barrel 16 projects slightly above it, being held by a screw 82, and the string 83 from the racket is wound around said cleat 8| to rmly hold it, so that rotation of said tightening device 64 pulls said string 83 tight, and when the indicator pointer 19 indicates on the scale that the string has been tightened to the point desired, the string is held by inserting an awl or other pointed instrument in the racket hole through which the string 83 passes on its way to the tightening device 64.

As will be seen, when the treadle 25 is depressed said pulley 65 is rotated, thereby tightening the string 83 from the racket, as the rotation of the pulley rotates said shaft 'I9 which in turn acts upon said spring 'l2 to rotate said barrel '18, and the scale 80 marked thereon.

In order that my machine may not only take 30 take a squash racket 89. This insert holder 81 40 is readily inserted by unscrewing the clamps which hold the racket, and when the insert holder 8'! is in place the clamps are tightened in the same manner as for the larger racket.

A pawl 9| having a tooth 92 which engages the 45 toothed portion 68 of the ratchet 61 pivots on a pin 93 which enters said bracket arm 49. A spring 94 is fastened at the free end of said pawl 9|, which spring is fastened by a screw 95 to a portion of said bracket arm 49, and serves to keep 50 the tooth 92 in position to normally engage the toothed portion 58 when it is presented 'to A handle 96 is fastened to said pawl 9| in order that said tooth 92 may be moved out of engagement with said toothed portion 68 of the ratchet when it is desired to have the tightening device 64 return to normal position. A stop pin 91 in the bracket arm 40 projects outwardly whereby the movement of said handle 96 is limited when pulling said tooth 92 out of engagement, as previously described. A stop member 98 on said ratchet 67 determines the normal position of said ratchet, and normally the said stop member 98 and said tooth 92 abut one another, as shown in Figure 7 of the drawings, thereby preventing any further clockwise movement of said ratchet.

To operate my machine the racket is laid on the top 48 and the clamps tightened against different portions of the bow head. The string 83 is inserted in holes in the said racket and when said string 83 comes through the hole in the racket nearest the tightening device it is wound around said cleat 8|, the foot lever 25 of the treadle is pressed, thereby rotating said tightening device and pulling on said string 83 until it 75 is drawn suiiiciently tight, then the string is held by inserting an instrument in the said hole in the racket, whereupon the foot lever is released, and the handle '96 is moved sufficiently to release the tooth 92 from the toothed portion 68 of the ratchet 6l, and the tension of the spring 12 causes said tightening device to return to normal position. The string 83 is then unwound from the cleat 8l and inserted through the next holes in the racket and the operation repeated. When the racket is ready for cross Stringing the holder is rotated sufficiently so that the direction of the Stringing to be done is towards the tightening device 64.

The construction should be noted wherein the top of the string tightening device 64 is lower than the top 48 so that the handle of the racket to be strung will not interfere with the operation of said device.

Through being able to determine the tightness of each string my machine makes it possible to preserve the original shape of the racket bow head, whereas when the Stringing is done by hand the fact that frequently oneV string is tighter than another pulls the bow head out of shape.

What I claim is:

1. A racket string tightening machine comprising in combination, supporting means adapted to support the racket to be strung, mechanism in juxtaposition to said means adapted upon actuation to tighten a string in a racket, andinstrumentalities connected to and adapted upon actuation to actuate said mechanism to thereby tighten said string, said supporting means embodying a -support for the racket, clamping means to hold the racket fast, and an insert holder supported by said support, and adapted to receive said clamping means, said clampingv means embodying members adapted to pass through said insert holder and engage with said support to thereby hold the racket to be strung in said insert holder.

2. A racket string tightening machine comprising in combination, supportingY means for a racket, a rotatable device adapted to receive and tighten a string in a racket supported by said means, and instrumentalities operatively connected to said device adapted upon actuation to rotate said device to thereby tighten said string, said device embodying a pulley, a ratchet adapted to hold said pulley in actuated position, a barrel, a spring in said barrel, and a shaft extending from said pulley into said barrel, and means interconnecting said pulley, ratchet, barrel, spring and shaft whereby rotation of said pulley actuates said shaft, ratchet, spring and barrel.

3. A racket string tightening machine comprising in combination, supporting means for a racket, a rotatable device adapted to receive and tighten a string in a racket supported by said means, and instrumentalities operatively connected to said device adapted upon actuation to rotate said device to thereby tighten said string embodying a cable, said device embodying a pulley adapted to receive said cable, a barrel, a spring, and a shaft extending from said pulley through said barrel embodying a cap, said barrel and said cap having provision to receive an end of said spring, and means interconnecting said pulley, barrel, spring and shaft whereby rotation of said pulley actuates said device.

4. A racket string tightening machine compris- Ving in combination, supporting means for a actuation of said pulley rotates said barrel tol thereby tighten said string.

5. A racket string tightening machine comprising in combination supporting means for a racket, a rotatable device adapted to receive and tighten a string in a racket adjacent said means, and instrumentalities operatively connected to said device adapted upon actuation to rotate said device i to thereby tighten said string, said device embodying a pulley adapted to receive and be actuated by said instrumentalities, a barrel, a coiled spring extending horizontally in said barrel, a shaft extending from said pulley through said spring and projecting beyond, said shaft embodying a cap at one end having provision to receive an end of said spring, said barrel having provision to receive the other end of said spring, and means to hold said pulley and shaft together to thereby operatively interconnect said pulley, barrel, spring and shaft whereby rotation of said pulley actuates said device.

6. A racket string tightening machine comprising in combination, supporting means for a racket, a rotatable device adapted to receive and tighten a string in a racket supported by said means, and instrumentalities operatively connected to said device adapted upon actuating to rotate said device to thereby tighten said string, said device embodying a spring connected to said rotatable device, and means operatively connecting said instrumentalities to said spring whereby actuation of said instrumentalities tensions said spring and thereby rotates said rotatable device.

'7. A racket string tightening machine comprising in combination, supporting means for a racket, a rotatable device adapted to receive and tighten a string in a racket supported by said means, and instrumentalities operatively connected to said device adapted upon actuation to rotatesaid device to thereby tighten said string, said device embodying a spring connected to said rotatable device, means adapted to hold said device in tensioned position, and means operatively connecting said instrumentalities to said spring whereby actuation of said instrumentalities tensions said spring and thereby rotates said rotatable device.

8. A racket string tightening machine comprising in combination, supporting means for a racket, a rotatable device adapted to receive and tighten a string in a racket supported by said means, instrumentalities operatively connected to said device to thereby tighten said string ernbodying a cable and means to actuate said cable to thereby rotate said device, said device embodying a pulley adapted to receive and be actuated by said cable, and a spring adapted to be tensioned, and means operatively connecting said spring to said rotatable device and to said cable whereby the actuation of said cable tensions said spring and rotates said device.

JOSEPH SALADINO.

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