US2608737A

US2608737A - Clamp for stringing rackets

Info

Publication number: US2608737A
Application number: US127804A
Authority: US
Inventors: Edmundo H Serrano
Original assignee: Individual
Current assignee: Individual
Priority date: 1949-11-17
Filing date: 1949-11-17
Publication date: 1952-09-02
Anticipated expiration: 1969-09-02

Description

P 1952 E. H. SERRANO 2,608,737

CLAMP FOR STRINGING RACKETS Filed Nov. 17, 1949 V T 40 6 IN EN OR By Serrana azq Patented Sept. 2, 1952 ;This invention relates certain new and useful Patents Nos. 2 ,188,250,dated January23, 1940,

on 2,154,870, dated April 18-, 1939, and more espe-' oi'ally .in the string tensioning device and string clamping or gripping :means 1 ofv the string i holding: arm thereof so'as to-prevent breaking of the string-when tension is placed thereonduring the stringing of the racket. 1 1 1 It is also an object of the invention .to provide a. novel string holding arm having .normally'expandeduorseparate'd jaws with heads designed to'receive and grip. the string therebetween" or permit wwrapping or winding of the string thereon: and gripping thereof betwee'nv the jaws when forced together so that the string does not take any abrupt anglesor bends and may withoutinjury thereto be safely placed under the desired tension during the stringing operation in proper line with the holes of the racket string frame so that breaking or parting of'thestring is guarded against, ltogether with a manually-actuated cam lever"'means for forcingjthejaws of-the puller ar'm'int'o string gripping or clamping relation or for releasing the same fohmoV'ement' automatically to. normally expan'ded'or separated position for further threading of the string-through the heads or drum in order to flrmlyclamp and hold or anchor the stringthereto when under tension during the stringing of the "racket, and the requirement of frequent replacement of such rubher band in order to effectively clampor anchor the string'to the holding arm. 5

A still-further and important object is to pro vide simpleand novel cam means for forcing the sections or jaws of the movable split holding arm together or forreleasing the camming action wherebythe' ja ws-willseparate to release'the grip old-the string,saidmeans including a forked ,U-NI-IEDq-STATES PATENr-oFFicE QoLAm ron KSTRINGINGRACKETSY-ZH e -LPF W t 1:3 Applieati onNovember 1'7, 1949, Serial No. 127,804 7 Claims. (01. 24-250 I 1 leverjstraddlingvthe normally expanded sections of the holding arm and a connection through the arm between the arms of the lever having coacting cam. surfaces washers. for efiecting the gripping and releasing action of the jaws of the holding arm'; a

. With the above and other objects in 'view that willzbecome apparent as the nature of theinvention'is'better understood,.the same consists in the novel form, combination and arrangement of parts hereinafter more fully described, shown in the accompanying drawings, and claimed.

Inthe drawing: I. 7 Figure 1 'is a. fragmentary perspective view showing a'portio'n of the-racket frame and the improved holding arm of the racket stringing apparatus of my ,prior patent with a section of the gutstring extending therebetween gripped or clamped and held under tension;

v Figure 2 is an enlargedfragm'entary inside elevation ofthe string'holding armwith the jaws 30 holes of the racket string irame'for completion in released position 7 Figure-3 'is' a: view similar to Figure 2 with the jaws in'clamping position; I

Figure 4 is an enlarged fragmentary vertical sectional view taken on line 4-4 'of Figur 1; 4

' Figure 5'is' a fragmentaryipcrspective detail view of one end of the squared belt or shaft of the jaw actuating cam means of the holding a-rm;

Figure 6'is a fraginentary detailof an'attaching end of the forked-cam actuating lever ofthe holding arm jaws,arid 7 Figure? is a detail face view of one "of the camming washers. 4 3

Referring-more-in detail to the accompanying drawing, the racket stringing apparatu to which the present improvement is applied, is of the type shown in my prior Patents Nos. 2,188,250, dated January 23,"1'94'0, or 2,154,870, dated April 18, 1939, hereinb'efore referred to, in which the string frame l0'of the racket is'held 'in clampsor jaws at the throat and nose portionsof the apparatusv in' the manner shown'i'n the patfint with the string ll eXtendingfthrough the staggered or otherwise arranged holesl l2 through the frame. The bar or rod [3 of the rectangular cross-section as shown, correspondstothe laterally oifset end slot the rod 29 of 'saidPatent 2,188,250, which slidably 'moves inthe anti-iriction bearings of the housings '28 atdiametrically. opposite sides of the upper end of thetubular post I0 .tocause movement of the'arm 32 o f the patent carrying the string 'grippingdruml for placin the string under t ension'. V 4. R H However, in the present'embodiment, the string holding arm is designated generally at 14, the

by swinging the lever or handle downwardly to permit the separation of the jaws under the action of the spring 27 as previously explained. The racket stringing apparatus is of course of the type wherein a string tensioning device is adapted to have a string coiled therearound and held or clamped by the gripping jaws to exert a holdin force on a string threaded through a tennis, squash or badminton frame and to be inefiective during continued movement after the string has received the desired tension, and wherein a tensioned portion of the string is held under tension while the tensioning device is being engaged with another portion of the string and wherein means is provided for holding the tension against movement, and, also, wherein a racket supporting head is mounted upon the upper end of a standard and wherein the string is tensioned by sections with a tensioned string section held under tension while tensioning another section, whereby with proper adjustment of the string tensioning means any racket frame may be properly and efficiently strung.

While there is herein shown and described the preferred embodiment of the invention, it is,

nevertheless to be understood that minor changes may be made therein without departing from the spirit and scope of the invention as claimed.

I claim:

1. In a string holding means for a racket stringing apparatus, string tensioning means including a string holding arm supported for tensioning and releasing movements, said arm including a rigid section and a pivoted section movable toward and away from the rigid section, enlarged outwardly projecting semi-ovate jaw heads on the upper ends of the sections having horizontally grooved outer peripheries and fiat substantially parallel inner faces, the inner corners of the heads being convexly rounded and the outer corners in alignment for winding a string thereon 2. In a string holding means for a racket stringing apparatus, string tensioning means including a string holding arm supported for tensioning and releasing movements, said arm including a rigid section and a pivoted section movable toward and away from the rigid section, enlarged equal sized outwardly projecting semi-ovate jaw heads on the upper ends of the sections having horizontally grooved outer peripheries and fiat substantially parallel inner faces, the inner corners of the heads being convexly rounded and the outer corners in alignment for winding a string thereon and between said faces, a shaft extending through the sections for rotation, said sections having diametrically concaved outer camming recesses at their outer sides, diametrically concavo-convex cam washers having their convex faces fitting said recesses, a polygonal bolt and between said faces, a shaft extending through extending through aligned circular bores through the sections centrally of the camming recesses with the washers fixed thereon outwardly of the recesses to turn therewith and slide thereon, a forked lever having ends fixed on the bolt to turn therewith outwardly of and against the washers to force the jaw heads and sections in contracted relation in one position of the lever to grip the string and release the same for expansion and separation in another position, and a spring between the sections to normally separate the same and jaw heads.

EDMUNDO H. SERRANO.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Great Britain May 18, 1933