US1655263A - Extension cord - Google Patents

Description

Jan. 3, 192s. 1,655,263

, H. H. FROST EXTENS I ON CORD Filed Dc. 1. 1924 .Hen-ferr if. .2U-a5 f y f Patented Jan. 3, 1928.

UNITED STATES PATENT OFFICE.

HERBERT H. FROST, 0F CHICAGO, ILLINOIS, ASSIGN OR, BY MESNE ASSIGNMENTS, T0

CHICAGO TELEPHONE SUPPLY COMPANY, `O14" ELKI-IART, INDIANA, A. CORPORA- 'rien or DELAWARE.

Application filed December In using a loud speaker in connection with a radio receiving set, it is citen desirable to have the loud speaker in a diterent rooml or at some point relatively distant trom the set itsel'it. Usually, as a matter ot practical expedience, the receiving apparatus is generally kept in some out-oI-the way spot where -it is not apt to be disturbed. Such a place, however, may not be suitable :tor listening in to the music, speeches, or what-l ever the nature of the matter may be which is being broadcasted. Unless means'are provided, therefore, to permit of the loud speaker functioning at a place which is more desirable roin the listeners standpoint, the inconveniences o the room where the set is actually located must be borne even though a more desirable one isavailable.

'lo eliminate this linconvenience to the radio listener, l provide an extension cord having a plug at one end which is adaptable for connection to the radio set, and a novel jack at the other end to which the loud speaker may be connected. The type or jack and plug used and the manner in which they are connected, are illustrated in the accom.- panying drawing. 1n the drawing:

Figure 1 is a plan view showing the connection of the plug of the loud speaker to the novel jack ot 4my invention;

Figure 2 is a sectional -view showing the manner in which the conductors leading to the plug and jack respectively are connected;

Figure 3 is another sectional view taken at right angles to the view of Fig. 2 ot' the plug and jack used in my invention showing, however, in greater detail the manner of constructing the jack;

Figure 4 is a plan view of the tip spring used in connection with the jack;

Figure 5 is a side elevational view of the sleeve to which the end of the extension cord is secured; and

Figure 6 is an end view of the sleeve.

One of the novel features of my invention consists in the provision of a suitable sleeve or housing 1 for the jack 8. The sleeve 1 is preferably made of a piece of ibre tubing although I may use what is commonly known and marketed under the trade naine of bakelite, or the like, and has pressed into one of its ends, a washer or ring 2 of the same material. An aperture 3 is EXTENSION' CORD.

1, 1924. Serial No. 753,032.

thus provided in the end of the housing through which the cord 4 may be freely adi mitted for connection with the separate contact members of the jack 8. In order to make tlie'sleeve as attractive as possible, I turn down the end ot the sleeve and the Washer to a smooth curve and finish.

The opposite end of the sleeve 1 is threaded to receive the mounting plateor block 5. A liuted or knurled flange the outer diameter of which is substantially equal to the outer diameter of the sleeve 1, is formed on the block or plate 5 and is provided for manually turning the plate 5 to thread it into or out or" the sleeve 1. An adjusting tliimble 7 having a hexagonal head and a threaded sleeve integral therewith snugly lits through the mounting screw 5. The threads on the sleeve are adapted to be received by the threads in the aperture contained in the leg of the jack trame 8. By

tightening the lhexagonal nut oi' the adjustin'g thimble 7 the threaded sleeve portion will draw the jack frame 8 against the end of the mounting screw 5 and thus keep it in a relatively fixed position.

Threaded into the base portion of the jack frame 8 are the screws 11. Between the heads of the screws 11 and the jack frame A8, thev contact and insulating members of the jack yare firmly held together. These consist of a ground spring, 12 which makes electrical lcontact with the jack lframe, of insulation strips 18, the tip spring 14, an insulation strip 15, and the metal Washers 16. Insulation bushings 17 separate the tip spring 14 from the screws 16. A novel means of connecting the extension cord 4 to the ground spring 12 and the tip spring 14 is provided in the use of the contact sleeves 18. The spring 14 together with one of the sleeves 18 connected thereto, is shown in plan in Figure 4. The tip spring 14 has a sharp bend 19 for engaging with the groove 2O in the tip of the contact member 21. In the body portion of the spring, openings 23 are provided into which the insulating bushings 17 are fitted to insulate the spring 14 from the .screws 11. An extending terminal member 24 integral with the body 22 serves as a means for connecting it with the contact sleeve 18.

Contact sleeve 18 is illustrated in greater detail in Figures 5 and 6 in which the Y or the like.

spring terminal member 24 is shown as tting into a diagonal slot 25. These contact sleeves may be stoel: items and a similar contact sleeve is connected to spring 12.V

Each sleeve has a flat side tace 26 and an eccentric longitudinal'opening 27 vforming a socket. The flat tace 26 is suitable for mounting thereon a contact of the spade type and the longitudinal opening 27 is suitable for inserting therein a contact ot the tip type. By means ofthe clamping screw 23 either type of contact may be firmly secured to the sleeve. The opening or socket 27 is oiiset from the center ot the relatively circular end of the sleeve 1S in order to provide sutilcient stock for the screw 28 so that it can clamp the terminal. This dispositionoic the fiat clamping face and the eccentric socket-permits reduction in the size of they sleeve 1 considerably thereby making the jack as a Whole more compact and more pleasing in appearance.

Y AThe jacket which encloses Vthe extension cord 4 terminates in a cord 44 Which is Wound around the insulating members 13 in order to take the strain off of the flexible conductors Which are connected to the sleeves 18.

The plug 30 which is connected to the opposite end of the extension cord 4 is identical With the plug 10 shown in Figures 2 and 3. This plug consists of a sleeve portion or housing 31 which may also be made of fibre', One of the ends of the sleeve 31 is down turned so as to form the opening 32 to permit the connecting cord 33 to be led therethrough. The cord 33 is provided With Contact tips 34 Which are adaptable for insertion into the sleeve members 35 and 41. Knurled thumb screws 36 serve as means for holding the tips 34 in fixed position in these sleeves. The sleeve 41 is rigidly secured in the member 37 of which the contact member 39 forms a part. The* sleeve -35 is insulated from the member 37 by the strip of insulation material V38. The electrical connection between the sleeve 35 and the contact member 21 is made by means or" the metal strip 42 and-a central needle,V (not shown), Which are rigidly connected to both. The insulating lWasher 43 and -a suitable sleeve o' insulation separate the contact y members 2l and 39 from each other.

The method ot using my extension cord may be brielycdescribed as follows: A suitable place for listening in is first determinedvupon. When this is done the plug 10 of the loud speakeris connected to the jack 9 tolwhich the extension cord 4 is secured. The cord is then led back romrthis point to the receiv-V ing set Where it isconnected tothe lset by means ot' the plug 30 thereby completing the circuit between the loud speaker and the receiving set. n

I do not intend to be limitedl to the de-y tails shown and described.-

Iclaim: *Y In electrical connecting means, a tubular casing of `electrical insulating material having an opening through one end to accommodate an Aelectric cord, a mounting block removably secured in the other end of the casing, a jack including a mounting frame disposed Within the casing and having an angularly disposed leg seatin on the inner face of the block, a. thimble aving a head on` itsrouter end andextending through the block, said thimble being threaded through the leg ot the jack frame and securingvit to Y' the block, and a resilient ycontact member carried by and electrically insulated from said trame, said member being disposed for contact with the terminal element of a plug shank inserted throuUh thev thimble. Y

In Witness Whereoi?, I hereunto subscribe my name this 26 day ofNovember, 1924.

: HERBERT H. FROST.

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