Abstract: A shutoff valve for installation in a gas distribution line to interrupt the flow of gas automatically upon a drop in pressure in the line due to a break or the like. The valve includes a movable valve member actuated by a piston which is disposed in a cylinder in communication with the distribution line. The top of the piston includes a calibrated aperture which admits gas into the cylinder beneath the piston so that the pressure beneath the piston in the cylinder is substantially equal to the pressure in the line. However, upon a sudden drop in pressure in the line due to a break or the like, the flow of gas through the aperture is metered so that the pressure in the cylinder beneath the piston becomes greater than the pressure in the distribution line, causing the piston to shift upwardly and move the valve member into a position where it interrupts the flow of gas. The pressure differential on the valve member retains it in the closing position.

Abstract: A laminated current surge protector comprising a flexible, conformable arrestor having a metal conductor encapsulated between a wear resistant tape adhered to the outer surface of the conductor and a dielectric tape adhered to the inner surface of the conductor. The arrestor is adhered to metal members by a bonding agent and extends across the joint between the members which includes an electrical insulating medium separating the members. The dielectric tape has a plurality of apertures therein exposing the encapsulated conductor to the metal members to provide a gap through which excessive surges of current in the metal members can pass through the conductor from one metal member to the other and thereby by-pass the joint and prevent injury thereto.