US316376A - Electric bueglae alarm - Google Patents

Description

(No Model.)

F. G. LYON.

ELEGTRIG BURGL'AR ALARM.

No. 316,376. Patented Apr. 21, 1885.

uarded fiuz'zclz'rg UNITED STATES PATENT OEFIOE.

.ERANK e. LYON, OF JERSEY crrY, NEW JERSEY, ASSIGNOR .ro THE HOLMES ELECTRIC PROTECTIVE COMPANY, OF NEW YORK, N. Y.

EL EG-T/RIC BURGLAR-AL'ARM.

Application filed September 29, 1884. (No model.)

SPECIFICATION Timing part of Letters Patent No. 316,376, dated April 21, 1885.

all whom it may conlxern: Be it known that I, FRANK G. LYON, of J ersey City, in the county of Hudson and State v of New Jersey, have inventeda certain new and useful Improvement in Electric Burglar- Alarms, of which the following is a specification.

This improvement relates to electricburglaralarms of the kind wherein an electric circuit extends from a house or other building which itis desired to guard to an ofiice where watchmen arekept.

It has occasionally happened with these burglar-alarms that burglars have forced open a door leading to a guarded building, hastily seized some valuables therein, and escaped before the watchman at the office could after hearing the alarm caused by the entrance of the burglars reach the guarded building.

The object of my improvement is to prevent burglars from successfully working in the manner described.

To this end the improvement consists in the combination of an electric circuit extending between a guarded building and an office 5 analogous fastenings of the door may be broken will not act to break the chain, and of such length that it will permit the door or like article to be opened wide enough to enable the circuit-closing device to operate.

A burglar breaking the lock, bolt. or analogous fastening of the door by; force exerted with a jimmy in the ordinary manner will find the door still secured by the chain, which will not have been broken in the act of breaking the lock, bolt, or analogous fastening. He will, however, have opened the door far enough to cause the circuit-closing device to operate, and hence the watchman at the office will have been apprised of his action. While a he is occupied in endeavors to sever the chain the watchmen will be afforded time to proceed toward the building. Through my improve ment, therefore, the kind of burglaries to which I have referred will be more easily frustrated.

In the accompanying drawings, Figure 1 is a diagram illustrating an office where watchmen are kept, the inner side of a pair of doors belonging to aguarded building, and'an electric burglar-alarm embodying my improvement. Fig. 2 is a view of a circuit-closing device used in the burglar-alarm, and Fig. 3 is a view of chain-sections and a padlock.

Similar letters of reference designate corresponding parts in all the figures.

I have marked the word Ollice upon that part of Fig. 1 which is intended to represent the office where watchmen are kept, and I have also marked the words Guarded Building upon the part designed to represent the 0 guarded building.

A A designate a galvanometer, A designating the coils and A the needle. The coils are connected together in the usual manner.

From the pivot of the galvanometer-needle 7 5 a wire, B, extends to an electromagnetic alarm-bell, G, thence a wire, B, extends to an electric battery, D, and thence a wire, B extends to contact-points E E, in conjunction with which the needle A of the galvanometer operates. Thewires BB B the electro-magnetic bell O, and the battery D are all in one local circuit, which is arranged in the office. Whenever the galvanometer-needle is deflected against either of the contact-points E E, it closes the local circuit and causes the electromagnetic bell to sound an alarm.

F designates an electric battery (shown as A arranged in the office.) One pole is connected by a wire, G, with one of the coils of the gal- 0 vanometer. The other coil of the galvanometer is connected by a wire, G, with a switch or key, H, which, as here shown, is pivotally' secured to the inner side of a door, I, belonging to the guarded building, so that it may 5 be swung into and out of contact with a congact-point, H, which is also affixed to the said oor.

From the contact-point H a wire, G extends to a resistance-coil, J, located in the guarded rco frame of the door.

building. This wire, before reaching the resistance-coil, is also electrically connected to a movable metal pin, K, comprised in a circuit-closing device, which is operated by the door I.

From the resistance-coil J a wire, G, extends to the battery F. This wire is also connected to a metal contact-piece, K, which is comprised in the short-circuiting device be fore referred to.

The circuit-closing device is secured to the It has a base-plate, K, which may be made of metal. The metal pin K before mentioned slides through it and another bearing which extends from the plate. This pin carries a metal contact-piece, K. A spring, K", surrounding this pin K between its rear bearing and the contact-piece K", impels the spring outward whenever it can. The contact'piece K is fastened to a block. K of wood or other insulating material, that is affixed to the base-plate K. This contact-piece K is resilient.

' When the door Iis closed,it presses the pin K inward against the resistance of the spring K. The contact-piece K is thus carried away from the plate K, and also away from the contact-piece K. The contact-pieee K owing to its resilience, also moves a slight distance away from the plate K. 4

When the doorI is opened even ashort distance, the pin K will move outward, and the contact-piece K will make contact with contact-piece K and force the latter against the plate K. The resistance-coil J will thus be short-circuited'and the galvanometer-needle will be deflected so as to cause the sounding of an alarm at the oifice.

The doc: I, shown, operates in conjunction with a door, I. The door I is fastened, as usual, by bolts, and the door I, whichis the master door, is fastened to it by a lock, bolt, or analogous fastening, L. Such fastening will hold the door closed tightly.

M M designate two sections of chain fastened one to the inner side of the door I and the other to the same side of the door I. A padlock, I, secures the free ends of these sections of chain together. The chain M M is so loose that force exerted by a jimmy or analogous implement to force the door I open will be so far expended before it acts on the chain that the chain will not be broken. It is also long enough to permit the door to open sufliciently far to allow the short-circuiting device to operate and short-circuit the resistance-coil, so as to cause an alarm at the oflice. It is not, however, long enough to admit a burglar past the door. The burglar endeavoring to effect an entrance into the guarded building has still to sever the chain or break the padlock. While he is engaged in efforts to do this the watchmen at the oifice will be afforded time to proceed toward the guarded building. ll may be frustrated in this =wa Preferably these chain-sections will comp se swivels m m, so that they cannot be broken by twisting them.

The ends of the chain-sections MM may be united by the padlock when door I is partially closed, and while the inmates of the guarded building are outside the door. They can accomplish this by thrusting their hands between the door I and the door I, slipping the hasp of the padlock through the end links of the chain-sections, and then locking the padlock. The door I may then be entirely closed and locked.

The keyH enables the inmates of the guarded building on returning to it to give a preconcerted signal, and thus indicate the diii'erence between themselves'and a burglar to the watchmen at the office.

Obviously the improvement is applicableto articles other than doors.

What I claim as my invention, and desire to secure by Letters Patent, is-

1. The combination of an electric circuit extending between a guarded building and an ofiice where watchmen are kept, a door or like article in the guarded building, a lock, bolt, or analogous fastening for the door or like article, a circuit-closing device operating to fulfill its function when the door or like article is opened partially, a chain preventing the door or like article from being opened sulficiently wide to admit a burglar, but made of such length that the force by which the lock, bolt, or analogous fastening of the door or like article may be broken will not act to break the chain, and of such length that it will permit the door or like article to be opened wide enough for the circuit-closing device to operate, substantially as specified.

2. The combination of an electric circuit extending between a guarded building and an office where watchmen are kept, a door or like article in the guarded building, a lock, bolt, or analogous fastening for the door or like ar-. ticle, a eircuit-closing device operating to fulfill its function when the door or like article is opened partially, a chain comprising swivels and preventing the door or like article from being opened sulllciently wide to admit a burglar, but made of such length that the force by which the lock, bolt, or analogous fastening of the door or like article may be broken will not act to break the chain, and of such length that it will permit the door or like article to be opened wide enough for the circuit-closing device to operate, substantially as specified.

FRANK G. LYON.

Witnesses:

T. J. KEANE, WVILLIAM G. LIPsEY.

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