| 摘要 |
1,220,828. Burners. BRITISH INSULATED CALLENDER'S CABLES Ltd. 26 Feb., 1969 [27 Nov., 1967], No. 53886/67. Heading F4T. A torch for flame heating a metal workpiece, e.g. jointing an oil-filled electric cable, welding, brazing, soldering, cutting, is connected through a valve assembly to a source of combustible gas, e.g. acetylene or propane and to a source of fire-extinguishing fluid so that in one operating position of the valve combustible gas only flows through the torch and in another operating position of the valve only fireextinguishing fluid is supplied through the torch. In a preferred embodiment, Fig. 1, the torch comprises a cylindrical body 1 terminating in a burner nozzle 31, a tube 3 for passage of fire-extinghishing fluid secured to and extending alongside body 1, its discharge end 34 encircling the nozzle 31 and having orifices 32 directed towards the same location as the end 33 of the nozzle 31, and a valve housing 4 secured to the body 1 and the tube 3. A plunger 6 is slidable in a bore 7 in the housing 4 and carries valve closure members 23 and 24 co-operating with seatings 21 and 22 in chambers 8 and 9 respectively, provided at either end of bore 7 and separated by an 0-ring seal 11 on the plunger 6. A spring 26 between the member 24 and an end cap 27 closing chamber 9 biases the valve assembly to the position shown in which fuel gas from a supply line 15 may pass through a handle 16 on the housing 4, and through the inlet and outlet ports 14 and 12 respectively of valve 21, 23 to the body 1. Depression of plunger 6 closes the valve 21, 23 and opens valve 22, 24 to permit fire-extinguishing fluid to flow through inlet 18 and outlet 17 to tube 3. In an alternative arrangement, the spring 26 biases the plunger 6 in the opposite manner to give a " dead man's handle " with a normal position allowing flow of fire-extinguishing fluid. Alternatively a spring-loaded ball or button in the torch body or plunger may co-operate with a depression in the other part to enable the plunger to be locked in a position permitting flow of fire-extinguishing fluid. The valve assembly may be located in the supply lines to the torch. The two supply pipes for gas and extinguisher may be replaced by a composite tube having formed therein at least two passages. In another embodiment the torch is of conventional form and the valve is a two-way valve so that either gas or extinguishing fluid pass through the same passage. In operation, a fluid-operated valve in the gas supply line is maintained open by the pressure in the extinguishing fluid supply line Fig. 2 (not shown). The extinguishing fluid may be a gas giving an inert atmosphere, e.g. carbon dioxide, nitrogen, or a flame-inhibiting material, e.g. bromo-chloro-di-fluoro-methane, methyl bromide, chlorobromomethane, freon, carbon tetrachloride, and a cartridge of such fluid may be carried by the torch. |
