摘要 |
The invention is to a safety valve for gas cylinders which includes a valve housing 11, a movable valve stem 11a within the valve housing for opening and closing the valve, a restrictor 15 in the valve stem through which gas is dispensed from the gas cylinder, a first shoulder 13 on the valve stem for sealing the gas cylinder when the valve is in a first position, a second shoulder 14 on the valve stem for limiting gas flow from the cylinder through the restrictor when the valve is in a second position, and a reduced section 11d of the valve stem, between said first and second shoulders, through which the gas cylinder is filled when the valve stem is in a position between said first and second positions. |