US723320A - Electric burglar-alarm. - Google Patents

Description

No. 723,320. V PATENTED MAR. 24,1903. Y

s. SCHWARZSGHILD.

ELECTRIC BURGLAR AL 'APPLIOATION FILED SEPT. 3, 1901. RENEWE NE 23, 1902. no MODEL.

2 QHEETS SHEET 2.

C1 Horne-v0 PATENTED MAR. 24, 1903. s. SOHWARZSOHILD.

ELECTRIC BURGLAR ALARM. APPLICATION FILED SEPT 3 1901 RENEWED JUNE 23 1902 no MODEL.

UNITED STATES SOLOMON SOHWARZSOHILD, OF ROCHESTER, NEW YORK.

ELECTRIC BURG LAR-ALARlV l.

SPECIFICATION forming part of Letters Patent No. 723,320, dated March 24, 1903. Application-filed September 3, 1901. Renewed June 23, 1902. Serial No. 112,867. (No 'model.)

To all whom it may concern:

Be it known that I, SOLOMON SCHWARZ- sCHILD, a citizen of the United States, residing at Rochester, in the county of Monroe and State of New York, have invented certain new and useful Improvements in Electric Burglar-Alarms; and Ido hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same,

This inventionrelates to improvements in;

electric burglar-alarms, and has for its principal object the utilization of a telephone-circuit for the transmission of the alarm-signal.

To this end the said invention consists in,

providinga building, dwelling, store, or room in whichis located an ordinary subscribers telephone instrument or into which passes an ordinary telephone-circuit with a local auxiliary or house circuit controlled by switches operated by the doors and windowsor otherwise and providing electromagnetic devices operated by said local circuit for sending a signal over the telephone-line to a desired up from the central exchange and notifiedthat a burglar-alarm call has been sent in from a certain locality. r y Obviously if the alarm system is located in a large building employing a substationexchange the alarm-signal would be sent there and not to the central exchange unless the latter course beespecially desired. a This invention contemplates also the employment in the local circuit of. time alarm apparatus and other devices, all of which will be hereinafter more fullydescribed and claimed.

Referring tothe accompanying drawings, Figure 1 is a diagram illustrating the principle of the invention. Fig. 2 is an enlarged detail sectional view taken through a portion of one of the doors and door-jamb, showing the door-switch in elevation; and Fig. 3 is a similar view of the window sash and frame and the window-switch. Fig. 4 is a detail view of the hook-switch retainingand releasing device, showing the same in side elevationand partly in section. Fig. 5 represents the same in front elevation, showing the contacts of the hook-switch. Fig. 6 represents the auxiliary time-switch in side elevation with its casing in section along the line 6 6 of Fig. 7. Fig. 7 represents the same in front elevation with its casing in section along the line 7 7 of Fig. 6. r

Similar characters refer to similar parts throughout the several views.

Referring first-to Fig. 1, A representsa subscribers telephone instrument-such, for exam ple, as that employed bythe Bell Telephone 'Oompanywith metallic circuits and central energy exchanges. The invention, however, is not confined to the Bell telephonecircuit alone, as there aremany so-called independent companies over whose lines the alarm will readily operate.

1 2 represent the subscribers metalliccircuit, and 3 4 the local house or alarm circuit. The latter circuit includes, among other parts, a switch B, located at each door and consisting of a contact-plate b and spring I), both preferably secured to the door -ja mb, the spring being countersunk, so that-when the door'is opened the said spring will engage the plate I), but when the door is closed the electrical connection between the two will be broken. (See Fig. 2.) Switches O O, similar to those located at the doors, are located at each window and so disposed that should the lower sash be'raised the spring 0' will make contact with the plate 0, owing to the cut-away portion 0 of the window-sash releasing the spring. Similarly the switch operated by the upper sash is closed upon the lowering of said sash. The local. alarm-circuit includes also a time-switch D, an electromagnetic device E fouretaining and releasing the telephone-hook switch, and a local battery or other source of electricity F. The hook-switch device E is preferably located at one side of the telephone and comprises, among other parts, a retaining-arm e, pivoted in a suitable frame 6 and adapted to extend across the top of the telephone-hook a, a latch 6 adapted to engage an extension 6 of the said arm and retain the said arm in a locked position, a spring 6 for raising said arm when released, and a pair of electromagnets 8", which are adapted when energized to attract an armature e carried by the latch 6 and thus release the arm e and telephonehook 0t. The time-switch D comprises simply a clock-escapemen-t train, upon the mainspring-shaft d of which is rigidly mounted a switch-arm d, which is adapted to engage an insulated contactplate 01 when the timetrain has run for a predetermined length of time, and thus to complete the local circuit, the said circuit passing into the time-switch through the binding-post d through the frame and mechanism to the arm d,and thence through the insulated contact (1 out through the preferably insulated binding post 01 When it is desired to set the switch, the arm (1 is shifted to the position shown in solid lines in Fig. 7, and by inserting a pin d in the casing, as shown, the said arm may remain set until it is desired to release it. The act of setting the arm (1 at the same time winds the spring of the clock-train, as will be readily understood. The entire mechanism of the switch is protected by being inclosed in a suitable case d, which may be secured to the wall or any convenient place.

When it is desired to put the system in an operative condition, which is usually done just before the house, room, or the like is vacated, the telephone-receiver a, is removed from its hook and the retaining-arm c is lowered until its catch-arm is caught by the latch 6 when it holds the said hook down just as though the said receiver had not been removed, and continues to keep the hook-switch of the main line open. The pin d of the time-switch D is then removed and the clocktrain allowed to run. The time elapsing between the moment the said time-switch is started and the time thatit closes the circuit may be of any desired length determined by the gearing, but should in any event be sufficient to enable the person to get out of the house and shut the door before it closes its contact.

The device shown in Figs. 6 and 7 will run for about five minutes before the switcharm (1 engages the contact d When the person goes out and closes the door, this opens the door-switch by pushing the spring I) out of engagement with the plate 1). Thus as long as the circuit is completed through the timeswitch D the. local circuit will be completed every time the door is opened and broken every time the door is closed. The object, therefore, of the time-switch is to keep the local circuit open when the burglar-alarm is not in operation; otherwise a call would be sent in every time the door was opened, whether by an authorized or an unauthorized person. Thus with the door and Window switches open, the time-switch closed, and the retaining device set as described the system is in the operative condition. The act of a person in opening the door or window will close the door or window switch, as the case may be. The local circuit will then be completed through the coils of the hook-releasing magnets 6 which will act upon the latch e and release the arm 6, allowing the telephone-hook to rise and complete the line-circuit through the hook-switch in the usual manner, and thus send a call to central. The central operator will then answer the call according to the usual practice; but upon receiving no reply will at once call up police or other headquarters and notify them of the fact, when they may respond and investigate the matter. Thus it will be seen that the ordinary subscribers telephone-circuit is utilized without tapping or in any way interfering with the telephone connections, the act of releasing the receiver-hook by the magnetic retainer being exactly the same in effect as lifting the receiver from its hook in the ordinary way.

The same explanation which applies to the doors applies to the windows, although in either case I do not confine myself to the specific form and. arrangement of the door and window switches shown, as various devices may be gotten up for accomplishing the same general result. Moreover, I may employ any suitable ti m e-switch, such as a clock-operated switch, well known in this art, in the place of the time-s witch shown, or in addition thereto, if desired. Indeed there are many changes which may be made in the invention without departing from the spirit thereof; but

What I claim, and desire to secure by Letters Patent of'the United States, is

1. In an electric burglar-alarm, the combination with a telephone-circuit, of a subscribers instrument connected therein, a 10- cal house alarm-circuit, and means operated by said alarm-circuit and operating the telephone hook switch of said instrument for sending an alarm-signal over said telephone,

circuit.

2. In an electric burglar-alarm, the combination with a telephone-circuit, of a subscribers instrument connected therein, and means independent of the telephone-receiver for retaining the hook-switch of said telephone instrument in the open position, a local housecircuit, and means operated by said local alarm-circuit for releasing said hook-switch and sending a call-signal over said telephonecircuit.

3. In an electric burglar-alarm, the combination with a telephone-circuit, of a subscribers telephoneinstrument located in said circuit, an electromagnetically-operated retaining device adapted to engage the hook of said telephoneinstrument and retain the hookswitch of said instrument in the open position, a local alarm-circuit including said magnetic retaining device, switches located in said circuit for operating said retaining del'IO vice and completing the telephonecircuit, whereby a call-signal is sent over said telephone-circuit.

4:. In an electric burglar-alarm, the combination with a telephone-circuit, of asubscribers telephone instrument located in said circuit, a pivoted retaining-arm adapted to engage the receiver-hook of said instrument and hold the hook-switch in the open position, a latch adapted to engage said arm and hold the same in a retaining position, an electromaqnet adapted to operate said latch and release said arm, a local house alarm-circuit SOLOMON SOHWARZSIOHILD.

Witnesses:

A. W. ST. JOHN, W. W. WEBB.

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