US1686051A - Means for preventing explosions - Google Patents

Description

Oct. 2, 1928.

H. C. P. WEBER MEANS FOR PREVENTING EXPLOSIONS Filed March 23, 1922 INVENTOR I Henry G P Weber BY WITNESSES 1 ATTORNEY Patented Oct. 2, 1928.

UNITED STATES PATENT OFFICE.

HENRY C. 1". WEBER, F EDGEWOOD PARK, PENNSYLVANIA, ASSIGNOR T0 WESTING- HOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- VAN IA.

MEANS FOR PREVENTING EXPLOSIONS.

Application filed March 23, 1922. Serial No. 546,003.

My invent-ion relates to protective devices, more especially to a device which is adapted to safeguard against explosions of gaseous mixtures which often accumulate in closed chambers, or the like.

It is among the objects of this invention to provide a protective device which may be connected in an electrical circuit-by an ordinary lamp socket and which shall function to remove dangerous combustible gases by burning, without danger of explosion.

It is a further object of this invention to provide an apparatus of the above-designated type which shall'be of simple and inexpensive construction and efficient 1n its operation.

My device is particularly adapted for use in subways, such as cable tunnels, where combustible gases often accumulate in explos ve mixtures and cause damage to the tunnel and cables. Explosions usually occur because of sparking produced at the contacts of switches and the like in the junction boxes of distributing systems. By placing my new device in the junction boxes this danger is eliminated.

In practicing my invention. I employ a filament or heated element which is adapted to become hot when a current is applied thereto. The filament or heated element is enclosed within a gauze housing for the purose of providing a chamber in which comustible gases may be burned without danger of igniting the' explosive mixture outside of the chamber. The principle of the gauze housing is the same as that of the Davey lamp which is commonly employed for mining purposes and other applications where portable illumination is desired in a place where gaseous explosive mixtures are likely to be present.

In the accompanying drawing, constituting a part hereof, and in which like reference characters designate like parts,

Figure 1 is a cross-sectional view, partially in elevation, of a protective device formed in accordance with my invention; and

Fig. 2 is a top plan view thereof, showing the construction of the top of the gauze housing.

I provide a filament or heated element 1 of suitable material, preferably of metal. such as nickel, which, when heated to a suitable temperature, from 600 to 800 C. in the case of nickel, is capable of catalyzing the oxidation or combustion of combustible gas mixtures. The filament is electrically connected to a standard screw-plug base 2 having an annular glass flange 3 extending therefrom. A housing, comprising a plurality of annular metal strips 4 and 5, flanged rings 6 and 7 and a plurality of tubular layers 8 and 9 of metallic gauze, is secured to the glass flange 3 in any suitable manner, as by screws 10. The gauze may be reinforced by longitudinal strips 11 clamped, at their respective ends, between the rings 6 and 7 and the flange 3 and the ring 4. The top of the chamber is covered with a plurality of layers 12 and 13 of gauze which are secured between the flanged rings 6 and 7.

The housing thus formed provides a combustion chamber in which the filament or heated element 1 is centrally disposed and WhlCll is adapted to be screwed in a socket connected in a lamp circuit or a junction box. The device functions as follows:

When combustible gases, such as sewer gas, natural gas or the like, accumulate in the space in which the device is located, they will penetrate into the gauze-covered chamber and be continuously removed by burning because of the air present at the hot filament, which hastens the combustion process. Conse quently, if such gases accumulate slowly they will be gradually consumed, avoiding the formation of an explosive mixture.

If a sudden in-rush of gas takes place, forming an explosive mixture, it will be burned up at the filament but the gauze housing will prevent flash-back of the flame into the main chamber. If the gas accumulation is continuous, the available oxygen in thechamber will be continuously combined with the combustible gases by reason of the agency of the hot filament, and the mixture will be rendered non-explosive by reason of the absence of sufficient ,free oxygen. From this it is evident that my device is capable of preventing explosions of accumulated gases under almost any condition.

Although I have described a specific embodiment ofv my invention, it will be obvious to those skilled in the art that various modifications may be made inthe details of construction thereof. For instance, the gauze housing in which the filament is contained may be of thimble form and be reduced by spinning the gauze to the desired shape. In

place of the double gauze illustrated, in most casesa single housing or gauze is sufficient. It may also be desirable to form a thermo-couple junction in the center of the filament to indicate temperature rises coincident with the contact of combustible gases with the heated filament. The glass flange of the base member may be replaced by metal or any other suitable material. The metal re inforcing strips may be eliminated from the gauze structure. In place of the bare filament, a filament or other body coated with materials to accelerate combustion, or a catalyzing body heated by the filament may be employed. These and other changes may be made in the details of construction of my invention without departing from the principles herein set forth.

I claim as my invention:

1. A protective device for consuming gaseous vapors comprising a filament composed of a metal capable of causing combustion of gaseous mixtures at temperatures ranging from 600 to 800 C., a base to which said filament is electrically connected and which is adapted to fit into a standard lamp socket, and a housing comprising a Davey safety lamp diaphragm secured to said base to provide a combustion chamber for said filament.

2. A protective device comprising a filament composed of a metal capable of causing combustion of gaseous mixtures at temperatures ranging from 600 to 800 C., a cylindrical gauze housing, a base to which said filament is electrically connected, said base having a glass flange and being adapted to fit into a standard lamp socket and said housing being secured to said flange to provide a combustion chamber.

3. A protective device comprising a filament composed of metal capable of causing combustion of gaseous mixtures at temperatures ranging from 600 to 800 0., a cylindrical gauze housing reinforced by metallic rings and strips, a base to which said filament is electrically connected and a glass flange secured to said base to support said housing, said base being adapted to fit into a standard lamp socket.

4. The method of preventing explosions in housings for electrical apparatus which consists in non-explosively burning gas as it collects in the housing and confining the combustion to a limited space Within the housing.

5. The method of preventing explosions in housing for electrical apparatus which consists in non-explosively burning gas as it collects in the housing and confining the combustion to a compartment shielded by a Davey safety-lamp diaphragm.

In testimony whereof, I have hereunto subscribed my name this 21st day of March,

HENRY C. P. WEBER.

Images