초록 ▼

A combined manual and pressure-responsive shut-off valve, intended particularly for use with high pressure gas cylinders, is disclosed. The valve includes a single seat and a single plug, the plug having a first sealing surface for closing against a low residual pressure in the cylinder and a second

A combined manual and pressure-responsive shut-off valve, intended particularly for use with high pressure gas cylinders, is disclosed. The valve includes a single seat and a single plug, the plug having a first sealing surface for closing against a low residual pressure in the cylinder and a second sealing surface for closing against a relatively high cylinder pressure. A pressure-responsive actuator engages the first sealing surface against the seat whenever pressure in the cylinder falls below a predetermined minimum. A manual actuator engages the second sealing surface against the valve seat to close against a wide range of pressures. The seat is specifically configured to conform to the plug. Means are provided for refilling the cylinder without removing the combined valve. In one embodiment, a special tool is provided for opening the pressure-responsive actuator. In a second embodiment, a bypass check valve is provided to allow gas to flow into the cylinder.

대표청구항 ▼

A shut-off valve for use with a pressurized gas cylinder, said shut-off valve comprising: a body having an inlet port, an outlet port, and a passageway therebetween; a seat disposed in the passageway; a plug having a soft surface for sealing against the seat to contain a relatively low pressure at t

A shut-off valve for use with a pressurized gas cylinder, said shut-off valve comprising: a body having an inlet port, an outlet port, and a passageway therebetween; a seat disposed in the passageway; a plug having a soft surface for sealing against the seat to contain a relatively low pressure at the inlet port and a hard surface for sealing against the seat to contain a relatively high pressure at the inlet port, said soft and hard surfaces being axially spaced apart so that the soft surface engages the seat before the hard surface engages the seat; pressure-responsive means for automatically engaging the plug against the seat with a first preselected force so that only the soft sealing surface engages the seat whenever the pressure in the cylinder falls below a predetermined level; and, manual means for engaging the plug against the seat with a second preselected force greater than the first preselected force so that the hard sealing surface engages the seat.