Discharge indicator for fluid containers

Aug. 1, 1967 b. _s hansom etal 3,333,641

DISCHARGE INDICATOR FOR FLUID CONTAINERS

Filed Feb. 17, 1966

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AttobnevS.

United States Patent Office _B³·³³³·⁶⁴¹

Patented Aug. 1, 1967

3,333,641 DISCHARGE INDICATOR FOR FLUID CONTAINERS

Bernard S. Hansom, 3 Foxherne, Turner Road, Langley, England, and Walter Leonard Abigail, IOS Grosvenor Road, Staines, England

Filed Feb. 17, 1966, Ser. No. 528,297 Claims priority, application Great Britain, Feb. 17, 1965, 6,740/65

Claims. (Cl. 169—26)

This invention relates to containers for fluids and the like, which term is intended to cover solids which are sufficiently divided to flow like a fluid. More particularly it relates to fluid containers having a normally-sealed discharge outlet which is unsealed to permit discharge of the contents of the container.

One example of containers to which the present invention may be applied are fire extinguishers which contain fire extinguishing liquid or powder.

According to the present invention there is provided a fluid container having a normally-sealed discharge outlet and comprising a member which is automatically displaced when said discharge outlet is unsealed, displacement of said member being adapted to sever an electrical conductor whereby when said electrical conductor is connected in electrical circuit with an electrically operated discharge-indicator the indicator is operated to indicate that the fluid container has been discharged.

The invention also provides a junction box cap for a fluid container comprising:

An open-topped cylindrical wall and a closed base, said base having a first aperture extending therethrough and having second and third apertures extending therethrough and located on diametrically opposite sides of said first aperture.

A pin having a head and a shank, the lower end of said shank fitting in said aperture and the head being positioned within the interior of the junction box cap, said shank having a transverse hole therethrough, and

A wire, said wire passing through said second and third apertures with a mid-portion of said wire extending through said transverse hole whereby said wire is severed by movement of said pin resulting from an impact of the head of said pin.

One construction of fluid container in accordance with the invention will now be described, by way of example, with reference to the accompanying drawing in which:

FIGURE 1 is a part-sectional side elevation of the container whilst,

FIGURE 2 is a sectional side elevation of the junction box cap of the container and which illustrates the electrical connections thereto.

This particular construction of container is designed to contain fire extinguishing liquid or powder in the bottle shaped cylinder 10. Prior to discharge the outlet of the cylinder 10 is sealed by a stopper 11 having a thin rim 11α which is severed by ignition of an explosive cartridge 12 when it is desired to discharge the pressurised contents of the cylinder 10. The stopper has a nut portion 11Z&gt; secured by an internal screw-thread 11c on the nut portion to an external screw-thread lid on the main stopper. The explosive gases resulting from ignition of the cartridge 12 enter the space 13 above the nut portion lib and apply pressure thereto which fractures the thin rim 11α, the stopper 11 being driven by the explosive gases into the cap 20 which is shown in detail in FIGURE 2.

The stopper 11 strikes the discharge indicator pin 21 and displaces it so that one end projects beyond the outer surface of the cap 20 and serves to indicate that the extinguisher has been discharged. When the indi10

25.

cator pin 21 is displaced by the stopper 11 it also serves to interrupt an electric circuit and this interruption of the electric circuit is used to cause a change of state in the operation of an electrically-operated indicator. The indicator shown diagrammatically at 25 may, for example, be electromagnetically operated and normally energized from an electrical source 26 so that when the circuit is interrupted the indicator 25 is de-energized, the de-energized state indicating that the extinguisher has been discharged.

It will be understood that the electrically-operated indicator may be located remotely from the extinguisher to provide a remote indication of discharge which is additional to the local indication provided by the projecting end of the shank 21α of the pin 21. On the other hand, whilst the projecting end of the shank 21α provides a local visible indication the interruption of the circuit may be used to operate an audible indicator additional to any remote visual indication.

The interruption of the electric circuit by displacement of the indicator pin 21 results from the fact that a portion 22α of an insulation covered wire 22 passes through a hole in the shank 21α of the indicator pin 21. When the pin 21α is displaced the wire 22 is severed. The wire 22 extends from both ends of the portion 22α to the exterior of the junction box cap 20 to provide electrical connections to the indicator 25 and source 26, this circuit being interrupted by severing of the wire 22 to effect operation of the indicator 25 upon displacement of the indicator pin 21. After shearing of the wire the two ends are retained in position in the junction box cap 20 by crimped sleeves 23 provided on the insulated covering of the wire 22.

To avoid any short circuit after operation the wire 22 is passed through holes in a washer 24 whose surface is electrically non-conducting. In addition any surfaces of the pin 21 which might come in contact with the severed ends of the wire 22 are rendered non-conducting. The pin 21 and washer 24 may be of aluminium which is anodized to render the surfaces non-conductive.