US3204222A - All relay warning system - Google Patents

Description

1965 K. MONTROY arm. 3,204,222

ALL RELAY WARNING SYSTEM Filed May 23, 1962 FIG. 1.

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5sEc. D I DELAY so 62 sol l I) BE CYOLER SIREN T3 "5 asEc nc- INVENTORS DELAY KENNETH MONTROY LAWRENCE E.COTTER ATTORNEYS United States Patent 3,204,222 ALL RELAY WARNING SYSTEM Kenneth Montroy, Morristown, N.Y., and Lawrence E. Cotter, 232 Washington St., Ogdensburg, N.Y. Filed May 23, 1962, Ser. No. 197,080 5 Claims. (Cl. 340-167) This invention relates to a warning system, and particularly to a warning system of the type which may be conveniently used in civil defense operations, though the system may be employed in other environments if desired.

As an improvement in warning systems, this inven tion contemplates and has for an object the provision of an all-relay control circuit for use between received input signals and output Warning devices to control the latter in accordance with characteristics of the input signals.

In a specific embodiment, the invention includes a receiver of conventional nature for example, which has an electro-magnetic relay connected to an output terminal thereof for operating a thermal relay if the electromagnetic relay stays operated for a predetermined length of time. The thermal relay, after a delay of that time, in turn actuates another electro-magnetic relay which controls a siren or other type warning device either for the length of time of the input signal or for a predetermined length of time as determined by a thermal relay or signal type timer connected to the last electromagnetic relay. The invention also includes apparatus for discriminating between different length input signals to cause the associated one of a plurality of warning devices to be operated in a particular manner.

Further objects, advantages, and specific embodiments of this invention may be appreciated more fully by reference to the following detailed description in conjunction with the attached drawings, in which:

FIGURE 1 schematically illustrates the invention in a basic form, and

FIGURE 2 schematically illustrates the invention in an advanced embodiment.

It is to be understood that in the operation of the warning system contemplated by this invention, signals may be transmitted over land line, or via the air as indicated by receiving antennas in FIGURES 1 and 2, to specify to the receiver 12 and the circuits which it controls that a certain warning function should be carried out. Whenever such a signal is received, relay 14, which is coupled to the output circuit of receiver 12, is energized to cause its switch 16 to close and control DC. current through the heater or filament 18 of a delayed action type thermal relay 20. If switch 16 stays closed for the predetermined length of time necessary, contacts 22 of the thermal relay close and conduct current through the coil of relay 24, causing its contact or switch 26 to close and energize the warning device or siren 28. If switch is open as illustrated, the siren will remain energized as long as the energizing signal to the coil of relay 14 continues to exist, assuming that signal exists a time longer than the heating or delay time required by thermal relay 20. The delay time associated with thermal relay 20 is for the purpose of preventing actuation of relay 24 and its associated warn- 3,204,222 Patented Aug. 31, 1965 ing device 28 by spurious signals received by antenna 10. As representative, the delay time may be 5 seconds.

When switch 30 is closed, the energization of the coil of relay 24 also causes its contact or switch 32 to close and provide current through the heater element 34 of another thermal relay 36. In this thermal relay, contacts 38 are normally closed, and current must pass through heater 34 for a predetermined length of time, say One minute, before these contacts 38 open. While they are closed, they effect a holding circuit, in that even though contacts 22 of thermal relay 20 reopen and break conduction of current to relay 24 therethrough, current nevertheless is conveyed thereto via the relay switch contacts 32 and the thermal relay contacts 38. switch 30 being closed of course. of operation of relay 24, and consequently of siren 28'.

In FIGURE 2, the control circuit is intended to distinguish and discriminate between incoming signal pulses of different duration. Regardless of the duration of the pulse received by antenna 10 and conducted to the output element of receiver 12 and thence to the coil of relay 14, that relay is energized thereby for the duration of the pulse and its switch 16 stays closed for that length of time, conveying DC. current to coil 40 of relay 42 which has one normally open switch 44 and three normally closed switches 46, 48 and St The output of the normally open switch 44 is connected in parallel to the heater elements of thermal relays T1, T2, and T3. These three thermal relays require heater current for different lengths of time to effect closure of their respective normally open contacts. As exemplary, relay T1 requires heater current for at least 2 seconds before its contacts close, relay T2 requires heater current for at least 5 seconds before its contacts close, and relay T3 requires heater current for at least 8 seconds before its contacts close. It will therefore be appreciated that if relay 42 is energized for at least 2 seconds, current via relay switch 44 during that period of time finally closes the contacts of thermal relay T1 and effects energization of the coil of electro-magnetic relay R1 via a set of normally closed relay contacts associated with electro-magnetic relay R2 and another set of normally closed contacts associated with electro-magnetic relay R3. When the coil of relay R1 is energized, its normally open contact closes, but since this contact is in series with the normally closed contact 46, which is now open, warning device 52 is not then energized through the fast operating, slow release relay 54. Relay 54 does operate, however, if the received signal ceases energizing relay coil 40 before the contacts of relay T2 close, since relay contact 46 then closes before relay R1 is deenergized.

If a received pulse exists 5 seconds or longer, the contacts of relay T2 close, and via a normally closed set of contacts on relay R3, energize the coil of relay R2. This opens the normally closed contacts of relay R2, thereby de-energizing relay R1. At the same time, the normally open contacts on relay R2 close, but since these are in series with contacts 48, the timer device 56, which may be like the timer in FIGURE 1, is not energized, nor is the warning device 58, unless the incoming signal ceases before relay T3 is energized. If this happens, coil 40 de-energizes and switch 48 recloses to complete the circuit to timer 56. In this respect, relay R2, and relays This times the length Q? R1 and R3 too, though they are of the fast operating type (i.e., actuate quickly) their release is slower, for example in the range of 0.2 to 0.5 second, meaning that their normally open contacts do not reopen before the normally closed contacts of relay 42 close at the end or" an incoming signal.

In a similar manner, if the received pulse exists 8 seconds or longer, the contacts of relay T3 close and energize the coil of relay R3. This disconnects energy from the coil of relay R2 by virtue of the opening of a normally closed set of contacts on relay R3. The normally open set of contacts on relay R3 immediately close, but due to the open contacts 50, cycler 60 is not energized to operate siren 62. However, when the incoming signal ceases, relay 42 is de-energized and its contacts 50 close before the normally open contacts of relay R3 open, thereby energizing cycler 60 and its warning device 62.

From the foregoing, it will be apparent that the apparatus in FIGURE 2 may be employed to distinguish between pulses of, say, 3 seconds, 6 seconds and 9 seconds when the contact closing times for thermal relays T1, T2 and T3 are respectively 2 seconds, seconds, and 8 seconds, for example. Generally speaking, however, pulse durations in the ranges t to t to I and t may be distinguished by this control circuit, t t and t respectively being the delay times of relays T1, T2 and T3.

The thermal relays referred to in FIGURES 1 and 2 may be of the type manufactured by the Amperite Com pany. Operation of the thermal relays is accomplished by the heating of a bimetal strip, which is surrounded by the heaters in the form of resistance wire. After a certain length of time, i.e., the delay time referred to above, the bimetal strip opens or closes, as the case may be, a set of contacts on its end. Because of the time necessary to dissipate the heat, a thermal relay does not return to its non-operative position immediately after current ceases to pass through the resistance heating element. Instead, the relay remains operated for a period that varies, according to the particular relay employed, between one-half and one and one-half times its operation interval.

It has been above indicated that the de-energizing or delay time of relays R1, R2 and R3 may be between 0.2 and 0.5 second, as long as it is longer than is required to open the associated normally closed contact of relay 42. The delay time, however, may be varied to a larger amount as required in accordance with the type of external circuit to be controlled. Where a sensitive timer is used, for example timer 56, a delay time of only 50 milliseconds may be sufiicient. If the relays directly control a horn for example a 30 second delay time might be desired so that the horn would emit a 30 second blast. Different control devices 54, 56 and 60 are illustrated to indicate that the different warning devices may be operated in any desired manner by the delayed relay con trol circuitry. For example relay 54 might be utilized to effect the above mentioned 30 second blast, while timer 56 might be of the type to give a longer warning signal than can be effected by a delay or slow releasing relay. Cycler 6t), once it is actuated, might cause operation of siren 62 in a cyclic manner with a particular length blast per cycle.

Thus, there has been described apparatus which will operate Warning devices in any desired manner intended.

Other modifications of this invention will become apparent to those of ordinary skill in the art after reading this disclosure, but it is not intended that the detailed drawings and description thereof be limitative, but only exemplary, the scope of the invention being defined by the appended claims.

What is claimed is:

1. A system operative upon receipt of predetermined length input signals to provide predetermined warning signals comprising a receiver for receiving transmitted signals, a relay coupled to said receiver for producing a relay output signal of length corresponding to the duration of the transmitted signal, a warning device, and means coupled between said relay and warning device for effectively rejecting relay output signals of less than a predetermined duration including means operative in response to cessation of each longer relay output signal to effect a connection to and operation of said warning device.

2. A system as in claim 1 including a second warning device, means for discriminating between relay output signals having respective durations in the ranges 1 to t and t wherein Z is said predetermined duration and i is a time longer than t and means coupling said discriminating means to said warning device for operating only said second warning device in response to cessation of a relay output signal of duration t or longer and operating only the first mentioned warning device in response to cessation of a relay output signal having a duration in the range t to 1 3. A relay control circuit for discriminating between input signals of different length comprising a control relay for receiving said input signals and making a normally open connection while breaking three normally closed connections, first, second, and third relay means connected at their inputs in parallel to the output of said normally open connection and operable in the order named at spaced successive times t t t as long as an input signal continues to exist, said first relay means being coupled to said normally open connection via said second relay means for causing the first relay means to release when the second relay means operates, said second relay means being coupled to said normally open connection via said third relay means for causing the second relay means to release when the third relay means operates, and the outputs of said relay means being respectively connected to said normally closed connections for preventing the completion of the output circuit of any of the relay means until the input signal to said control relay circuit ceases and the said normally closed connections reclose to complete the output circuit of the said first, second, or third relay means according to whether the input signal had a duration in the time range t t0 t t to t or greater than t 4. A Warning system operative to distinguish between diiferent length input signals to effect different warning signals comprising means for receiving said input signals to make a first connection and break three normally closed connections during the time an input signal exists, a first relay set including first, second, and third relays having a respective set of normally open contacts closeable after progressively longer times t t and t respectively, said relays being connected in parallel to the aforesaid first connection for energization thereby in accordance with the length of input signal received, a second set of three relays having coils respectively coupled to the contacts of said first, second, and third relays, each of said three second set relays having a respective normally open contact with the second relay thereof having one normally closed contact and the third relay thereof having two normally closed contacts, the third relay of said second set being coupled directly to the first set third relay contacts while said second relay of said second set is coupled to the first set second relay via one of said two normally closed contacts with the other of those contacts along with the said one contact of the second relay of the second set serially coupling together the said first relays of each said set to cause successive de-energization of the said second set relays as an input signal to said first relay set increases its duration to cause the next one of those relays to close its contacts, first, second, and third warning devices re spectively coupled to said normally open contacts respectively on said second set relays, and means serially References Cited by the Examiner colupling saidhnormally opeln colntacts of said second set UNITED STATES PATENTS re ays with t e said norma 1y c osed connections respectively for preventing operation of said warning devices Ega until the end of the corresponding input signal, whereby 5 2637822 5/53 Kin S16 said warning devices are respectively operated following 2958755 11/60 i y 317 139 cessation of input signals in the ranges t to t t to t d FOREIGN PATENTS 5. A system as in claim 4 wherein the relays in said 526,239 9/40 Great B i i first set are thermal relays and those in said second 10 set are electromagnetic relays. NEIL C. READ, Primary Examiner.

Claims (1)

1. A SYSTEM OPERATIVE UPON RECEIPT OF PREDETERMINED LENGTH INPUT SIGNALS TO PROVIDE PREDETERMINED WARNING SIGNALS COMPRISING A RECEIVER FOR RECEIVING TRANSMITTED SIGNALS, A RELAY COUPLED TO SAID RECEIVER FOR PRODUCING A RELAY OUTPUT SIGNAL OF LENGTH CORRRESPONDING TO THE DURATION OF THE TRANSMITTED SIGNAL, A WARNING DEVICE, AND MENS COUPLED BETWEEN SAID RELAY AND WARNING DEVICE FOR EFFECTIVELY REJECTING RELAY OUTPUT SIGNALS OF LESS THAN A PREDETEMINED DURATION INCLUDING MEANS OPERATIVE IN RESPONSE TO CESSATION OF EACH LONGER RELAY OUTPUT SIGNAL TO EFFECT A CONNECTION TO AND OPERATION OF SAID WARNING DEVICE.

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