Abstract: A safety valve for attachment to a gas cylinder. It has a body rigidly attachable to the port of a gas cylinder, with an inlet and an outlet. A valve between the inlet and outlet is held open by a fragile stem that is maintained in tension. When sufficient bending forces are exerted on the safety valve the stem breaks, its parts move apart from one another, and the safety valve closes.

Abstract: A linear actuator with a pair of in-line piston-cylinder combinations, separated by a partition. The combinations are supplied from a common source of fluid under pressure through a single inlet port. A guide pin prevents the uppermost piston from cooking, and serves as an upper limit stop. The pistons are biased into abutment with one another.

Abstract: A valve, particularly for smaller sizes, with minimized envelope size and dead volume. Its body is comprised of two seamless parts, one inserted into the other and welded together with a single weld. This weld is the only joinder of the two parts. The inserted part has a valve seat and a free end which is cantilevered freely into the other part so the free end does not contact the other part. Closure means and actuator means are provided to control the valve.

Abstract: A warning for a vehicular air brake system, which system is powered by air compressed by a rotary compressor. A sensor senses rotation of some part of the compressor, and if a signal respective to rotation is not sensed during a predetermined increment of time, an alarm is caused to alert the operator of an impending lack of compressed air.

Abstract: A fluid pressure regulator having a flow path from inlet port to outlet port. Reduction of particulates which might be generated by the regulator itself are minimized by the absence of springs, freely moving parts, and rubbing contacts in the flow path, and by minimizing the cavity volume.

Abstract: A protection system for internal combustion systems which indicates and alarms the loss of coolant liquid which it detects as a pressure drop at higher temperatures, and then sets off an alarm.

Abstract: A gas supply system including purge means. A supply conduit having an inlet and an outlet and a downstream direction of flow has within it a purge conduit with an inlet and a discharge port. The discharge port is directed upstream in the supply conduit and discharges adjacent to its inlet, whereby to purge that region of the supply conduit and to sweep gases from the entire supply conduit. The system is also provided with a selector valve able selectively to deliver gas to a delivery conduit or to a vent conduit or to shut them both off.