US2000074A - Supervised electric system - Google Patents

Description

May 7,' 1935. H. c. GRANT. JR

SUPERVISED ELECTRIC SYSTEM Filed March 8, 1928 Patented May 7; I935 UNITED STATES PATENT OFFICE sornvrsan anaemic srs'rau Application Marc]: 8, 1928, Serial No. 259,958 '0 Claims. (oi. 111-455) This invention relates to alarm systems, for iire,.burglary, etc., in which a thermostat or other circuit closer is connected across the two main leads of the electric alarm, and a resistance 5 is connected across the main leads beyond the circuit closer or series circuit closers, so that under normal conditions a supervisory current flows through the resistance and the trouble relay serving to energize the trouble relay which 10 normally holds open the circuit of the trouble alarm, while upon the operation of a thermostat or other circuit closer the full current causes the alarm relay to close the circuit of the main alarm through flre, burglary, or other principal 15 alarm. In case 01' derangement of the alarm continue to ring until the trouble is cleared, or the bell circuit is opened manually. It the bell circuit is opened there is no certainty that it will be closed again after the trouble is cleared and 30 there may be thereafter, therefore, no supervision oi' the remaining circuits, that is, no means by which derangement of such other circuits will be indicated. The purpose in view in the present invention is to overcome these practical diillculties in the operation of the system and to provid means whereby the particular circuit which has become deranged shall be indicated and shall continue to be indicated by a visual indicator even after the audible trouble alarm or bell has been stopped. and whereby the audible alarm or bellshallcontinuetobesoconnectedastosound on the derangement 01 any other circuit. The invention will be more fully explained hereinafter with reference to the accompanying drawing in which:

l 'lgure l is a diagrammatic representation 01 an alarm system constructed and arranged in accordance with the invention.

Figure 2 is a similar view illustrating a modiii cation.

In the system shown the battery it is connected through a feeder b with the main leads c 01' the several local circuits, of which two are represented. Thermostats or circuit closers d, of which-there may be several in each local circults is deranged. Furthermore, the bell will cuit, are connected across the main leads 0, c and outside of the most remote circuit closera resistance e is also connected across the main leads. The return lead 0 oi each local circuit, including an alarm lamp or "other visual indica- 5 tor c, is connected by a wire 0 through the coils oi an underload trouble relay I, back to the return leg b oi the main circuit, which includes the coils of an overload or main alarm relay 0 which I controls the alarm circuit and for convenience may be called the alarm relay to distinguish it from the trouble relay above mentioned.

When the system is in normal condition, with no circuit closer closed, the current which flows through the resistance e and the coils of the trouble relay 1 is suflicient to energize the relay I but is not sufilcient to energize the relay 0 which has a diirerent winding. Each trouble relay 1 controls two contacts! and I. both being connected on one side, through the wire I, with the return leg b 01' the main circuit. The armatures or movable contacts I and f cooperate respectively with contacts I and I, the former of which is connected by a wire I, including a local visual indicator, such as a lamp f", with the main leads 26 c of each local circuit. The other contact 1 is connected through a wire I and an audible alarm," such as a bell f, with the leg b of the main circuit. At f in each line 1 is a switch, manually controlled and of the usual toggle variety, inca- 30 pable of remaining in an intermediate position, which serves to connect the line i, with its visual indicator I", either with the relay controlled contact f or with the main lead 0 c or each local circuit. So long as the system is normal each local trouble relay f holds the movable contact I away from the fixed contact i, butshould the local circuit become deranged so as to prevent the flow of current the relay 1 will release the movable contacts I and I and permit current to flow through the visual trouble signal f of the corresponding local circuit, and through the audible signal I which is common to all of thelocal circuits. The audible signal, it it be a bell, will continue to ring until the break in the local circuit is repaired and the relay 1' again picks up the movable contact or until, as contemplated, the switch f is moved toward the left to establish connection between the line c -and the line I, thus again causing 'a current to flow through the relay 1' whereby the relay f picks up its movable contacts, thereby opening the circuit through the audible signal I. As a result, the local visual indicator or lamp f' will remain lighted to indicate a derangement 0: the circuit and it will remain lighted even after the local circuit trouble has been repaired, so as to indicate that the local circuit is still cut on from the audible trouble signal.

I. To extinguish the lamp f' the switch I! is moved toward the right to establish connection with the fixed contact I Since the local circuit trouble has been repaired, current will again flow through the relay I so that the movable contacts will remain up and the local circuit will again be in condition to indicate derangement. The relay 0 is not energized by the current which fiows when the system is in normal condition, but it any one of the circuit closers d in any of the local circuits is operated, as by the outbreak of fire or the intrusion of a burglar, the resistance e will be short circuited and the current will flow, energizing the relay 0 and causing it to pick up its armature or movable contact a and close the circuit through the fixed contact a and through the line a and main audible alarm or bell a conveniently referred to as the fire alarm. The current, under these conditions, also operates the corresponding local circuit visual indicator or lamp c.

It will be seen that the system, as described, will indicate which of any number of local circuits is deranged, and will permit the common audible circuit alarm or bell to be stopped by bypassing the current through the trouble relay I and causing it to pick up its armatures and so open the circuit to the bell, and will not cut out.

the bell in any local circuitother than that in which trouble has been indicated, the bell in every other local circuit being always so connected as to operate in the event of derangement of that local circuit. Alter the break in the local circuit has been repaired the lamp I in that circuit will remain lighted when the local relay is again energized and will remain lighted thereafter until the switch 1 is thrown to the right to interrupt the current through the lamp.

It will be seen that the modified system shown in Figure 2 is identical with that shown in Figure 1 except for the-arrangement of each visual indicator f and corresponding switch I with respect to the relay I and its contacts I and I, as the parts are shown in Figure 1. In thesystem as shown in Figure 2 each trouble relay I controls two contacts I and I which cooperate respectively with contacts I and I the former I being connected, as before, by a wire I through a lamp I with the main leads c of the local circuit, the-other, I being connected, as before, through a wire I and bell I with the leg b of the main circuit. The manually controlled toggle switch I is in this instance connected into the leg I and is adapted to establish connection therefrom either to the terminal I of the wire I or with the heel I 0! the contact I". With this arrangement, in the event of failure of the supervisory current in the local circuit, as for example, by the breaking of a wire, the relay I will be de-energized, allowing its armatures to close the contacts at I and I whereby circuits are closed through the trouble lamp I of the corresponding local circuit and the trouble alarm I. The circuit through the trouble alarm bell may be opened by moving the switch I to the left to establish contact at the point I. The lamp I remains lighted even during the movement of the switch I because of the contact established at the'point I. As soon as the derangement of the local circuit is repaired the relay I will be energized and will pick up its movable contacts, but the lamp I will continue to be lighted by reason of the connection estabarrangement shown in Figure '1 current is bypassed through the lamp I'! and the relay I. A further diflerence is that with the arrangement shown in Figure 2 the lamp I remains lighted even while the switch I is being moved from one contact to the other, while with the arrangement shown in Figure l the lamp I" is temporarily extinguished during the movement of the switch.

I claim as my invention:

1. In an electric alarm system of the type wherein'a plurality of circuits are provided each of whichincludes a source 0! electrical energy and a relay 'coil, the combination of two circuits controlled by each relay and independent of the plurality of circuits, one of each of the last named circuits including signalling means of a substantially non-objectionable. nature to the senses, and the other thereof including signalling means having a signalling eilect of a nature objectionable to the senses, and a switch and connections to close the circuit through a first signalling means and disconnect the second signalling means from actuation by a particular local circuit whilst leaving the second signalling means connected for actuation by any one of the remaining local circuits, said connections maintaining the circuit through the first signalling means closed until the last named switch is opened.

2. In an electric alarm system of the type wherein a plurality of circuits are provided each.

of which includes a source of electrical energy and a relay coil, the combination of two circuits controlled by each relay'and independent of the plurality of circuits one of each of the last named circuits including signalling means of a substantially non-objectionable nature to the senses, and the other thereof including signalling means having a signalling effect oi a nature objectionable to the senses, and a switch and connections to close the circuit through a relay and a first signalling means and disconnect the second signalling means from actuation by a particular local circuit whilst leaving the second signalling means connected for actuation by any one of the remaining local circuits, said connections maintaining the circuit through the first signalling means closed .until the last named switch is opened.

3. In an electric alarm system of the type including signalling means having a signalling ef-' fect of a nature objectionable to the senses, circuit closing means in the last named circuits operated by said relays, and additional circuit clostbminfrom thenbe ing means in a circuit including a first signalling means to maintain the first signalling means in" an energized condition and disconnect the sec and signalling means from actuation by a particular local circuit whilst leaving the second signalling means connected for actuation by any one of the remaining local circuits, said connections maintaining the circuit through the first signalling means closed until the last named closing means is opened.

4. In an electric alarm system of the type wherein a plurality of circuits are provided each of which includes a source of electrical energy and a .relay coil, the combination of auxiliary circuits controlled by the relay coils including signalling means of a substantially non-objectionable nature to the senses, second circuits controlled by the relay coils including signalling means having a signalling eflect of a nature obiectionable to the senses, circuit closing means in the last named circuits operated by said relays, additional circuit closing means in the auxiliary circuits including the first signalling means and including means to efiect deenergization 01' the second signalling means with respect to a particular local circuit whilst leaving the second signalling means connected for actuation by any one of the remaining local circuits and to maintain the first signalling means in energized condition, said connections maintaining the circuit through the first signalling means closed until the last named closing means is opened.

5. In an electric alarm system of the type wherein a plurality oi local circuits are provided each of which includes a source of current and a relay coil, and having a visual signal for each local circuit and an audible signal common to all of the local circuits, the combination at two circults controlled by each relay, a visual signal in one of the circuits and the audible signal in the other of the circuits, a switch, and connections to disconnect the audible signal from actuation by a particular local circuit and to maintain the connection to a visual signal corresponding to the relay that has operated closed, the audible signal remaining connected for actuation by any one of the remaining local circuits, said connections maintaining the circuit through the first signalling means closed until the last named switch is opened.

6. In an electric alarm system 0! the type wherein a plurality of local circuits are provided each or which includes a source oi. electrical energy and a relay coil, the combination of a plurality of auxiliary circuits each including independent signalling means of a substantially nonobjectionable nature to the senses, a plurality of second auxiliary circuits including common signalling means having a signalling eflect o! a nature objectionable to the senses, all said auxiliary circuits being independent of the plurality 01 local circuits, circuit closing means in the auxiliary circuits including the first signalling means including means to disconnect the second signalling means with respect to a particular local circuit, said closing means maintaining the circuit through the first signalling means closed until opened.

HARRY CAMPBELL GRANT, Jr.

Images