US3052185A

US3052185A - Electric switch

Info

Publication number: US3052185A
Application number: US441190A
Authority: US
Inventors: Apstein Maurice
Original assignee: Individual
Current assignee: Individual
Priority date: 1954-07-02
Filing date: 1954-07-02
Publication date: 1962-09-04
Anticipated expiration: 1979-09-04

Description

p 1962 M. APSTEIN 3,052,185

ELECTRIC SWITCH Filed July 2, 1954 INVENTOR Maurice Apsfein ATTORNEYS w P it States i Filed July 2, 1954, Ser. No. 441,190 2 Claims. (Cl. 102-28) (Granted under Title 35, U.S. Code (1952), see. 266) The invention described herein may be manufactured and used by or for the Government for governmental purposes without the payment to me of any royalties thereon.

The present invention relates to electrical circuits for supplying large amounts of power to utilizing means. More particularly, it is an electrical switch or air thyratron which is capable of completing an electrical circuit within a few microseconds following receipt of a firing signal.

It is known that the products of combustion resulting from the explosion of a primer will ionize the space immediately surrounding the primer. It then two terminals of a circuit are located near to one another and within influence distance of the primer, the circuit can be made conductive due to the fact that the primer, when activated, causes the space between the said terminals to become ionized.

One object of this invention is a circuit for supplying large amounts of power to a load within a few microseconds of receipt of a firing signal.

Another object of the invention is a superquick switch for completing the circuit when the power is needed.

A further object of the invention is a dependable and economical switch means for electric circuits.

A still further object of the invention is a compact device for supplying large amounts of power to a load within a few microseconds of receipt of a firing signal.

The specific nature of the invention as well as other objects and advantages thereof will clearly appear from the following description and drawing in which:

The FIGURE is a schematic electrical circuit diagram of the invention.

It is necessary in some applications to activate a plurality of detonators or blasting caps within ten microseconds or less from receipt of a firing signal. This may require several thousand volts at peak currents in excess of one hundred amperes.

The present invention provides a dependable and economical means for supplying great amounts of power to the utilizing means within a very short interval of time after the need arises. In order to maintain the circuit normally open, the switch terminals must be consider ably separated in order to prevent the charge from jumping the gap between the terminals. -It is apparent that to close that large gap mechanically in so short a time would require a tremendous amount of power. The equipment necessary to supply that power would be unreasonably large and expensive.

The ignition or conventional thyratron is also impractical for completing the circuit since a tube of suflicient size to handle such a load would be unreasonably large and would require very high power in its filament and plate circuits.

The present invention is a one shot device. it essentially destroys itself in its one use. in addition, the device is intended to be used where space is at a premium. For these reasons there is a requirement that the device be quite small and inexpensive.

In the figure, a small explosive charge or primer 7, connected in series with a battery 9 and a switch 10, is mounted near a pair of terminals 6. Terminals 6 are 3,952,185 Patented Sept. 4, 1962 separated by an air gap of, for example, approximately inch, and primer 7 is located at a distance, for example, of approximately /2 inch from terminals 6. Terminals 6 are connected in series between a number of parallel-connected electric detonators 1 and a charged capacitor 4. When the system is in the ready but quiescen state, capacitor 4 is in the charged condition and preferably is charged to a substantial voltage-at least several hundred or several thousand volts, for example. It will be understood that, when the system is in this state, the voltage to which capacitor 4 is charged will appear across terminals 6.

To fire detonators 1 by means of energy stored in capacitor 4, primer 7 may be exploded by closing initiating switch 10. The products of combustion resulting from the explosion of the primer 7 will ionize the region between terminals 6. Persons familiar with phenomena of electrical discharges through gases will understand that, if the voltage across capacitor 4 and terminals 6 is appropriate in relation to the spacing of terminals 6, these combustion products will initiate an electrical discharge between terminals 6. During this discharge the effective resistance between terminals 6 is relatively low, and a large amount of energy from capacitor 4 flows into detonators 1 in a short time.

It will be understood that the entire sequence of operation, from the closing of switch 10 through the explosion of detonators 1, may be very rapid, and that the application of a relatively very small amount of electrical energy to primer 7 upon the closing of switch 10 may sufiice to cause a relatively tremendous amount of electrical energy to discharge across terminals 6 and through detonators 1.

Means which may include a generator 3 and a switch 5 may be provided for charging capacitor 4- to ready the system for operation.

Those skilled in the art will readily understand that the primer 7 need not be particularly powerful and tremendous mechanical ruggedness is therefore not necessary. Making terminals 6 and their supporting structure sufiiciently rugged to withstand the detonation of primer 7 can readily be accomplished with ordinary skill. In most contemplated applications of the invention, terminals 6 need to retain their approximate original posi tions only sufiiciently long to pass sufficient energy from capacitor 4 to fire detonator 1.

It will be apparent that the embodiment shown is only exemplary and that various modifications can be made in construction and arrangement within the scope of the invention as defined in the appended claims.

I claim:

1. Means for initiating a flow of current between two terminals of unequal electrical potential and separated by an air gap, said means comprising: an explosive primer device located near said terminals, and means for exploding said primer device, said primer device being constructed and arranged so that the products of combustion resulting from the explosion of said primer device ionizes the region between said two terminals thereby creating a low resistance path between said two terminals.

2. A high power detonator-activating circuit comprising in combination: a capacitor, means for charging said capacitor to a substantial voltage, a detonator having one of its terminals connected to one terminal of said capacitor, a pair of terminals spaced by an air gap connected between the other terminal of said detonator and the other terminal of said capacitor, an explosive primer device located near said terminals, and means for exploding said primer device, said primer device being constructed and arranged so that the products of combustion resulting from the explosion of said primer device ionize the region between said two terminals forming a low resistance path therebetween, said capacitor 2,331,058 Stick Oct. 5, 1943 4 Windes July 11, 1950 Mufily Dec. 30, 1952 Coleman Dec. 6, 1955 Brimley et a1. Apr. 9, 1957 FOREIGN PATENTS France June 24, 1953