US315152A - Bubglar alakm - Google Patents

Description

UNITED Srnrns `"'PATENT OFFICE.

IRA G. LEEK, OF SAN FRANCISCO, CALIFORNIA.

BURGLARALARM.

SPECIFICATION forming part of Letters Patent No. 315,152, dated April '7, 1885.

(No model.)

To all whom t may concern:

Beit known that I, IRA G. LEEK, of the city of San Francisco, in the county of San Francisco and State of California, have invented an Improvementin Door-Alarms; and I here by declare the following to be a full, clear, and exact description thereof.

My invention relates to an alarm device to be used upon doors for the purpose of announcing the opening of the door or the entrance of a person into the room; and it consists of a gong or bell with a disk supporting a hammer and operating mechanism having a central opening through the two for the introductio'n of the shank of the door-knob, the gong and the disk occupying the place of and forming a rosette,which is secured to the inside of the door between the door and the knob.

In the accompanying drawings,Figure l is a view of my device in place upon a door. Fig. 2 is a view of the disk with the bell removed to show the mechanism.

A is a flat disk or plate, which may be about the size of anordinary rosette, which is tted upon the door, and through which the knobshank passes, or it may be somewhatlarger,

if desired. This disk has a centralhub, B,

projecting inwardly, with a hole through it of sufficient size to allow the square knobshank to pass through freely.

C is a bell or gong of about the same or a little larger diameter than the disk, made very shallow, and having a central hole with screwthreads fitted to screw upon threads on the outside of the hub B.

D is a hammer,with an elastic arm extending around the periphery of the disk in such a manner that when the hammer is drawn back and afterward released it will strike the inside rim of the gong. The plate F, to which the hammer-shank is xed, has a notch at E,wit h which the end of the arm G engages. This arm is pivoted to the plate A at H, as shown. A slot or channel is cut through the side of the head B to receive the disk I ,which has a square hole th rough its center, through which the shank of the knob may pass.

J is an arm projecting from side of this disk I and engaging with the angle of the arm G, 5o so that if the knob be turned in either direction the arm J will act upon one side or the other of the angular lever G and force it outward. The point of this lever, engaging the notch E of the plate F, draws it backward around its pivot-pin K, thus drawing the hammer D toward the center until the end of the arm G has passed the notch E and released the plate F, when the spring L acts to draw the plate back to its rst position and causes the hammer to strike the bell. The outer end of the plate F strikes against a pin, M, which acts as a stop.

The lever-arm G has va spring, N, acting against it to force it back to its original position when the door-knob is released, and the arm J will thus be carried to its position in the angle or" the lever G.

In order to allow the point of the lever G to pass the projecting lug E of the plate F, the plate is slotted, as shown at O, and the pin K, xed to the disk, projects through this slot. Vhen the point of the lever G presses upon the back of the notch E, it pushes the plate to one side of slot O, allowing of this movement 75 until the point of lever G has fallen inside notch E, when the spring L acts to draw back the plate to its original position, and it is then ready for the operation of the knob again.

When it is desired to have the knob operate without sounding the gong or bell, the plate F may be thrown back so that the notch E is out of Contact with the point of thelever G, when the latter may be moved by the turning of the knob without acting upon the plate 8 5 F or the hammer.

The gong C will be made of small diameter and shallow in depth, so that itself and the disk A will occupy but little more space than an ordinary rosette,which is placedupon all 9o doors. This bell is out of the way, being close'against the side of the door and inside of the line of the knob. It may be made ornamental, and will not be noticeable except on close inspection. N o connecting rods or wires 95 are necessary, and the whole is very compact.

Having thus described m y invention, what I secured thereto, all constructed and arranged claim as new, and desire to secure by Letters to sound an alarm When the knob is turned in Patent, iseither direction, Vas herein described.

An alarm for doors, consisting of a gong In Witness whereof I have hereunto set my 5 secured to the door and having a hole through hand.

the center to admit the shank of the doorknob, a hammer having an elastic arm, a plate IRA G LEEK to which said arm is attached and which is Witnesses: provided with a notch, a pivoted angular M. J. SEELY, 1o lever, G, a central hub, B, disk I, and arm S. H. NOURSE.

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