US3646540A

US3646540A - Tornado alarm

Info

Publication number: US3646540A
Application number: US874872A
Authority: US
Inventors: Roy L Cooper
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-11-07
Filing date: 1969-11-07
Publication date: 1972-02-29
Anticipated expiration: 1989-02-28

Abstract

The tornado alarm consists of a simple TV-type tube circuit adapted to receive radio signals from an approaching tornado to light up the tube with a sustained brightness which is detected by an electric eye circuit to operate an alarm or warning signal of the approach of the tornado in time for taking all precautionary measures possible against loss of life or property damage. A barometric pressure switch is included in the alarm control circuit to make it operative only if the barometric pressure is substantially reduced, in order to prevent operation of the alarm should there be a local disturbance created accidentally to brighten the TV tube when there is no tornado in the vicinity.

Description

O Elmted States Patent vus] 3,646,540 Cooper, deceased 1 Feb. 29, 1972 [54] TORNADO ALARM OTHER PUBLICATIONS [72] Inventor: Roy Cooper, deceased, m of watelu Popular Mechanics: Now You Can See Tomados On TV" man In by Alberta M Cooper heir by Henry and Vera Bradshaw; March, 1969; pages 93- 96,

H 2 25, 226 [73] Assignee: Lynn F. Laseman, Waterman, III. a part interest Primary Examiner-Thomas B. Habecker t Assistant ExaminerDaniel Myer [22] Filed: Nov. 7, 1969 Atmme), waher pawl [21] Appl. No; 874,872

[57] ABSTRACT [52] U S Cl 340/241 178/6 73/170 The tornado alarm consists of a simple TV-type tube circuit 51] g 21/00 adapted to receive radio signals from an approaching tornado [58] d 5/67 78 to light up the tube with a sustained brightness which is dele 0 are l tected by an electric eye circuit to operate an alarm or warn- 324/20 250/226 217 ing signal of the approach of the tornado in time for taking all precautionary measures possible against loss of life or proper- References cued ty damage. A barometric pressure switch is included in the alarm control circuit to make it operative only if the baromet- UNITED STATES PATENTS ric pressure is substantially reduced, in order to prevent 3,189,780 6 1965 T k t L "250 21 x operation of the alarm should there be a local disturbance 3 536 831 wily/0 g g s al 7 created accidentally to brighten the TV tube when there is no 2,298,757 10/1942 Evans et al ..340/23'/ s 3,40l,33l 9/ i968 Mussulman ..324/20 3C 1 Drawing Fig? l A Potentiometer Light Control l6 Amennq I4 =:============:H 9 Contgzt snnormolly Photoelectric TV 24 Switch Tube f j 22 Magnetic Relay Switch Res ponsive to Prolonged L L Brightnessof f Tube 3?) l I l 26 I I 1 II Aneroid 22 Switch M25 5:352 Responsive to 6 H0 V AC Input Low Pressure TORNADO ALARM Tornado alarms, which use only the telltale sudden reduction in barometric pressure as a means for causing the operation of the alarm, have been found in the prior art, such as shown in U.S. Pat. No. 3,029,422. These alarms can not be relied on to distinguish a tornado from the relatively harmless storms with moderate winds. Any mild storm may produce a sudden drop in barometric pressure, depending on the speed at which the center of the storm is moving relative to the location of thealarm. Furthermore, in the event a tornado approached such an alarm which was electrically operated, there is the chance that the storm would knock out the power lines and the alarm would fail to provide the warning when it was mostly needed.

The main object of the present invention is to provide a dependable battery-operated warning system capable of definitely distinguishing a tornado from the less violent and more common storms, so as to avoid false alarms but assure a definite warning in every case of a tornado approach, even if it ripped out the power lines.

A further object is to provide an electrically operated alarm system which will operate even under conditions of failure of its normal power supply.

A further object is to devise a tornado warning system in which an electrically operated alarm is responsive to the bright glow on a TV-type tube screen affected by the proximity of a tornado in its approach toward the TV receiver, in time for the alarmees to take cover until the tornado passes.

A further object is to provide this alarm with an operating circuit having a normally open relay switch which will close only if a low barometric pressure is present indicating the proximity of a storm, thus to prevent operation of a false alarm in response to extraneous radio disturbances which could brighten the TV tube at times when no tornado was in the vicinity.

Other and more specific objects will appear in the following detailed description of one form of the present invention, as illustrated in the accompanying drawing, wherein:

The single FIGURE illustrates diagrammatically the arrangement of parts and electrical circuits connected therewith in the novel tornado alarm system.

It has been observed in operating TV receivers, that the tube brightens up with a steady glow during the passing of a tornado in the vicinity of the receiver, within a radius of up to 20 miles or more. In the midwest where tornadoes are quite violent, tests were made by turning on a TV set and after warming it up, the set was switched to channel 13. This higher frequency does not normally indicate a tornado, but the brightness control was adjusted so that the screen was almost black. Then the channel selector was turned to channel 2, which is the lowest frequency band (around 55 megacycles) on a TV, and was found to be the best one for receiving a tornado signal. Lightening appeared as bright flashes or streaks, but when a tornado approached the TV tube was brightened with a continuous glow which increased in brightness as the tornado came closer and dimmed as it moved farther away. Signals were picked up from funnels 15 to 20 miles away, giving as much as 30 minutes warning. However, whenever the screen went white, there was little time to take cover and prevent injury due to property damage and flying objects. Thus used the TV receiver was found to be an excellent warning system. However, a tornado will usually rip out power lines in its path, and your TV then becomes useless.

n the other hand, a TV receiver might provide a false alarm in response to some extraneous sources of signals similar to those generated by a tornado, e.g., a passing motorist may be operating a mobile short wave transmitter, generating a signal on a resonant frequency, causing the tube to brighten into a false alarm.

The alarm system of the present invention will not respond to such exitation unless there is simultaneously present a substantially reduced barometric pressure, sufficient to indicate the proximity ofa tornado.

Although it has been estimated that the wind velocity in a tornado funnel may reach as much as 500 miles per hour, the speed of travel of the destructive funnel over the surface of the earth is generally at a speed of from 5 to 20 miles per hour. The friction of this vicious whirling wind produces a continuous generation of lightning or electromagnetic flux which penetrates the atmosphere for many miles.

It has been definitely found that any TV set which is turned to channel 2 or in the 52-55 megacycle range, will be caused to light up when a tornado is in the vicinity even though the TV tube is adjusted to extremely low light intensity, almost black. This lighting up is caused by the electromagnetic influence of the tornado which may be as far as 20 miles away.

Another characteristic of every tornado is the substantial drop in atmospheric pressure. In fact the drop in pressure inside of the flue of the tornado is so great that when it passes over a house, pressure is removed from the outside and the house virtually explodes because of the substantially higher atmospheric pressure enclosed therein. In the vicinity around the tornado the pressure drop is not so great, however there is still a definite drop from average normal pressure for several miles from the tornado.

For this reason, a normally open aneroid switch, which may be adjustable, is used in the present system to guard against false alarms, since it has to be closed by a suitably low atmospheric pressure indicating the proximity of a tornado, before the alarm can be sounded or flashed, as the case may be.

In the drawing, the signal device 10, which may be an undulating sound or light, is operated upon closure of the normally open relay switch 12 in response to energization of the photoelectric switch circuit 18 upon its detection of a bright glow on the screen of the TV-type tube 14 through the photoelectric eye 34, when a tornado approaches to cause such bright glow. The light shield 32 prevents entrance of any external light effects that might interfere with the operation of the photoelectric switch circuit by the glow of the TV screen.

The tube 14 is lit by a SZ-megacycle transistorized power unit 22 which is controlled by a potentiometer 16 to reduce the normal lighting glow of the tube to a minimum. The continuing signals from a tornado in the vicinity are received by this power unit through its antenna 24 to increase the brightness on the screen of the tube 14 to a degree that will energize switch circuit 18 provided aneroid switch 22 is closed by a low atmospheric pressure due to the approach of a tornado; this activates the photoelectric cell in the switch circuit 18 only if the low atmospheric pressure switch 22 is closed at the same time that the tube 14 is glowing brightly.

This system is powered by a battery 26 across which a battery charger is connected through a constant duty relay 30, which is normally closed by an electromagnetic coil tapped into the v. AC power supply to the battery charger 28. When a tornado rips out the power lines, the failure of the power supply to the battery charger deenergizes the magnetic coil of the relay switch 30 and releases the switch to its normally biased open position. This, however does not disable the system, which continues to operate on the battery power alone, whereas normally the battery power would be supplemented by the AC powered battery charger circuit, which would simultaneously provide a continuous trickle charge for the battery.

Many obvious modifications in the details and arrangements of parts in this system may be made without departing from the spirit and scope of this invention.

What is claimed is:

1. A tornado alarm system comprising a signal device,

an electrical circuit for operating said signal device and having a normally open relay switch therein,

a TV tube,

an operating circuit for said TV tube including a 52-55 mc.

power unit having a potentiometer for controlling the brightness of the glow produced on the screen of the tube, said potentiometer being set to reduce said brightness to a suitable minimum,

an antenna connected to said power unit for receiving radio signals generated by a tornado so as to substantially increase the brightness on said screen,

a photoelectric switch in front of said screen,

a control circuit for activating said photoelectric switch in response to said increased brightness to close said normally open relay switch in said circuit for operating said signal device, and

a normally open aneroid switch in said control circuit responsive to a suitably reduced barometric pressure to close and energize said control circuit for activating said photoelectric switch.

2. A tornado warning alarm system comprising an electrically operated signal device operated by a circuit having a normally open relay switch,

a TV tube operated by a 52-55 mc. power unit set to produce a minimum glow on the screen of the TV tube,

a photoelectric switch having a circuit for closing said normally open relay switch in response to a substantial increase in brightness of said screen caused by radio signals received by said power unit from a tornado in the vicinity, and

a normally open barometric pressure switch in said photoelectric switch circuit closed by low pressure incident to the proximity of said tornado to energize said photoelectric switch circuit only when a low pressure accompanies the radio signals.

3. A tornado warning alarm system comprising an electrically operated signal device operated by a circuit having a normally open relay switch,

a photoelectric switch having a circuit for closing said normally open relay switch in response to a substantial increase in brightness of said screen caused by radio signals received by said power unit from a tornado in the vicinity,

said TV tube comprising a light-producing tube operated by said radio frequency power unit at low power in said 52-55 mc. range and adjusted to produce minimum brightness on the tube screen and adapted to receive said radio signals to brighten said screen,

a photoelectric eye circuit responsive to said increased brightness to close said normally open relay switch, and an activating circuit for said electric eye circuit having a normally open aneroid switch therein responsive to a suitably low barometric pressure incident to said tornados proximity for closing said aneroid switch to operate said activating circuit.

Claims

1. A tornado alarm system comprising a signal device, an electrical circuit for operating said signal device and having a normally open relay switch therein, a TV tube, an operating circuit for said TV tube including a 52-55 mc. power unit having a potentiometer for controlling the brightness of the glow produced on the screen of the tube, said potentiometer being set to reduce said brightness to a suitable minimum, an antenna connected to said power unit for receiving radio signals generated by a tornado so as to substantially increase the brightness on said screen, a photoelectric switch in front of said screen, a control circuit for activating said photoelectric switch in response to said increased brightness to close said normally open relay switch in said circuit for operating said signal device, and a normally open aneroid switch in said control circuit responsive to a suitably reduced barometric pressure to close and energize said control circuit for activating said photoelectric switch.

2. A tornado warning alarm system comprising an electrically operated signal device operated by a circuit having a normally open relay switch, a TV tube operated by a 52-55 mc. power unit set to produce a minimum glow on the screen of the TV tube, a photoelectric switch having a circuit for closing said normally open relay switch in response to a substantial increase in brightness of said screen caused by radio signals received by said power unit from a tornado in the vicinity, and a normally open barometric pressure switch in said photoelectric switch circuit closed by low pressure incident to the proximity of said tornado to energize said photoelectric switch circuit only when a low pressure accompanies the radio signals.

3. A tornado warning alarm system comprising an electrically operated signal device operated by a circuit having a normally open relay switch, a TV tube operated by a 52-55 mc. power unit set to produce a minimum glow on the screen of the TV tube, a photoelectric switch having a circuit for closing said normally open relay switch in response to a substantial increase in brightness of said screen caused by radio signals received by said power unit from a tornado in the vicinity, said TV tube comprising a light-producing tube operated by said radio frequency power unit at low power in said 52-55 mc. range and adjusted to produCe minimum brightness on the tube screen and adapted to receive said radio signals to brighten said screen, a photoelectric eye circuit responsive to said increased brightness to close said normally open relay switch, and an activating circuit for said electric eye circuit having a normally open aneroid switch therein responsive to a suitably low barometric pressure incident to said tornado''s proximity for closing said aneroid switch to operate said activating circuit.