E Dn Dn A U u C M L J. 8. 4|/ 00 3 6 nm N APPLIANC'E FOR TELEPHONE SWITCHBOARDS.

(Application led Apr. 10, 1897.)

(No Model.)

mw l UNITED STATES PATENT OFFICE.

JAMES L. MCQUARRIE, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE IVESTERN ELECTRIC COMPANY, OE SAME PLACE.

APPLIANCE FOR TELEPHONE-SWITCHBOARDS.

SPECIFICATION forming part of Letters Patent No. 638,418, dated December 5, 1899.

Application filed April 10, 1897. Serial No. 681,533. (No model.)

To all whom it #tag/conocan' extremity to form a bearing-surface for the Be it known that I, JAMES L. MOQUAERIE, heel of the plug and to abut against the bota citizen of the United States, residing at Chitom of the countersunk socket Zi. At its cago, in the county of Cook and State of Illilower extremity the tube c carries a conical 55 5 nois, have invented a certain new and useful collar d, of hard rubber. The expanded head Improvement in Appliances for Telephonec and the collar (l are placed at such a dis- Switchboards, (Case No. 1,) of which the foltance apart that the tube is permitted a slight lowing is a full, clear, concise, and exact delongitudinal play, one-eighth of an inch bescription, reference being had to the accoming sufficient. As illustrated in Figs. 4, 5, 6o

1o panying drawings, forming a part of this and G, the outer walls of the tube are flatspeciiication. tened or cut away, so that the tube does not My invention is a plug-seat switch for use fill up the hole in the socket entirely. This with connecting-plugs in telephonesswitchis for the purpose of allowing dust that may boards for the purpose of changing circuits alight upon the switch-table to fall through 65 15 automatically in the removal of the plug from and out in the space thus left between the its normal resting-socket or its replacement outer wall of the tube and the bore of the therein. socket. I have made this provision because The object of the invention is to produce a otherwise dust would be liable to collect in plug-seat switch which shall be operated by the socket and cause the tube to stick. 7o

2o the weight of the plug and its attached cord The switch-springs e and f are iiat springs and shall be of simple and durable construcfastened at their upper extremities to the tion. block a. Their lower extremities are curved My new plug-seat switch comprises a verinwardly and brought to bear upon the intically-movable tube or sleeve, through which clined face of the collar d, so that when the 7'5 5 the cord passes, extending into a restinglatter is forced downward the springs are socket of the plug and having an enlarged spread apart. The springs should exert sufhead adapted to receive the plug, a tapered ficient pressure upon the collar d to raise the or conical collar carried on the free portion tube to the upper limit of its range of moveof the tube, and switch-springs having free ment when free, but should of course yield un- 8o 3o extremities bearing upon the oblique surface der the Weight of the plug and cord when the of the collar. latter rest upon the tube. Normal resting- The invention is shown in the attached contacts g and h are provided for the springs drawings. e and j", secured to the base Ct. Of course any Of the drawings, Figure 1 is a side elevaother desired arrangement of contact-points 85 35 tion of a plug-seat switch. Fig. 2 is an end or switch-springs may be made.

elevation of the same. Fig. 3 is a vertical Having thus described my invention, I central sectional View. Fig. e is a plan View claim as new and desire to secure by Letters of the switch, the plug and cord being re- Patentmoved. Fig. 5 is a detail View of the verti- 1. The combination with a base having a 9o 4o cally-movable tube or sleeve, and Fig. 6 is a vertical perforation formed init, of a tube in cross-sectional view of the tube and socket. the perforation longitudinally movable,a con- Similar parts are designated by similar letical collar on the tube, switch-springs hav- L ters of reference wherever they are shown. ing free extremities bearing on the inclined The parts may be mounted on a base or faces of the collar, and contact-anvils for the 95 45 block d,of insulating material. In this block switch-springs, a connecting-plug resting on a vertical perforation b is drilled, having a the upper extremity of the tube, and the cord countersunk portion b', adapted to receive thereof passing through the tube, as dethe base or handle of the plug. In this openscribed. ing is placed a tube c, of metahiitting loosely, 2. The combination with a base having a zoo 5o so as to be freely movable. This tube is provertical perforation and a countersunk upper vided with an enlarged portion o' at its upper portion constituting the plug-socket, of a tube longitudinally movable in the perforation, switch-contacts actuated by the tube in its longitudinal movement, the tube having YHattened longitudinal faces formed on it to per- 5 mit the escape of dust from the Socket, as described.

3. The combination with a base having` a vertical socket therein, of a tube movable longitudinally within said socket, said tube bezo ing; ent away to 'form dnst-passages between it and the inner Wallof the Socket, and switcheontaets adapted t0 be actuated by the movementof the tube, substantially as described.

In Witness whereof I hereunto Subscribe my naine this 21st day of November, A. D. 1896. I5

JAMES L. MCQUARRIE.

lVitnessee:

ELLA EDLER, DUNCAN WILLETT.