Gas heated tool with control valve and refillable container

A gas burning appliance comprising a container of pressurized gas and a differential valve for controlling the flow of gas from the container, in which the valve comprises an apertured member providing an outlet for gas from the container, a chamber on the downstream side of the outlet, a movable diaphragm forming a wall of the chamber, a conduit for the supply of gas from the chamber, a valve operating member arranged for movement with the diaphragm, a valve closure member biassed to the closed position on the upstream side of the outlet by a resilient means, the valve operating member being movable axially in a direction to move the valve closure member to an open position, and control means for exerting a biassing force on the diaphragm and valve operating member in the valve opening direction, characterised in that secondary sealing means are arranged to close the outlet on the downstream side thereof upon continued movement of the valve operating member, in the same direction, beyond the position at which the valve closure member is in the open condition on the upstream side of the outlet.

A gas burning appliance having a refillable container of pressurised gas, the container including a gas outlet valve and a gas inlet valve for refilling purposes, the inlet and outlet valves being biassed to the closed position, characterised in that means are operatively connected between the inlet and outlet valve whereby upon opening of the inlet valve for refilling purposes an additional closing force is transmitted to the outlet valve.

A gas container for use with a gas burning appliance, the container having a valve to be controlled in use by a valve operating member provided for the appliance, said container comprising an apertured member providing an outlet for gas from the container, and a valve closure member biassed to a closed position on the upstream side of the outlet by a resilient means so that in use axial movement of the valve operating member causes the valve closure member to move against the biassing force to permit the flow of gas from the container, characterized in that a connecting member is joined to the valve closure member and extends through the outlet, and a second valve closure member is joined to the connecting member on the downstream side of the outlet, whereby in use continued axial movement of the valve operating member causes the second valve closure member to close the outlet on the downstream side.

A tool as claimed in 1 characterised in that there is a predetermined high run condition with a maximum gas flow and with a mixture intermediate said relatively rich and said leaner mixtures.

A gas burning appliance comprising a mixture supplying conduit for feeding gas/air mixture to a combustion region, a jet for introducing pressurised fuel gas into the conduit, a gas flow valve for varying the flow of gas from the jet, air admission means of variable flow cross-section through which air is drawn into the conduit to mix the gas, and control means for simultaneously adjusting the gas flow valve and adjusting the air admission means, characterised in that the control means includes a cam and cam follower arrangement operatively connected between the gas flow valve and the air admission means, the cam having a profile which at least in part determines the relationship between the degree of adjustment of the gas flow valve and the degree of adjustment of the air admission means so as to provide gas/air mixtures and gas flow rates.

A refillable gas container for use with a gas burning appliance, comprising an outlet valve at one end thereof biassed by means within the container to a closed position, and gas inlet valve at the other end thereof for refilling purposes and biassed by means within the container to a closed position, the inlet valve being openable by engagement with refilling means, characterised in that the gas inlet and gas outlet valves are disposed opposite each other and interconnected by spring means providing the respective biassing forcers, so that a force tending to open the inlet valve for refilling purposes is transmitted as an additional closing force to the outlet valve.

A differential gas valve for use with a gas burning appliance, comprising an apertured member providing an outlet for gas from a source of pressurised gas, a chamber on the downstream side of the outlet, a movable diaphragm forming a wall of the chamber, a conduit for the supply of gas from the chamber, a valve operating member arranged for movement with the diaphragm, a valve closure member biassed to the closed position on the upstream side of the outlet, the valve operating member being movable axially in a direction to move the valve closure axially in a direction to move the valve closure member to an open position, and control means for exerting a biassing force on the diaphragm and valve operating member in the valve opening direction, characterised in that secondary sealing means are arranged to close the outlet on the downstream side thereof upon continued movement of the valve operating member, in the same direction, beyond the position at which the valve closure member is in the open condition on the upstream side of the outlet.