Apparatus used in mines, in order to indicate the presence of vapors or inflammable gases

摘要

547,452. Detecting inflammable gases. RING- ROSE, H. T. May 31,1941, No. 6992. [Class 1 (i)] In a detector for inflammable gas comprising a porous vessel 8 in which a partial vacuum is produced by the combustion of gas on a heated filament, a quantitative indication is obtained by the use of a vacuum gauge 39 in conjunction with the porous vessel. To minimize free space in the vessel the filament 9 is mounted in a recess 11 in a boss 5 depending from the cover 4 of the vessel, and radial passages 12 are provided in the boss to facilitate circulation of the gas. The porous wall 3 of the vessel is surrounded by an annular space 21 which may contain an absorbent to maintain a constant humidity in the air entering the chamber and which is bounded by an apertured wall encircled by a hit and miss apertured valve ring 24 for controlling communication between the porous vessel and the atmosphere. The device may be combined with an inspection lamp 19 and screwed on to a battery container (not shown). A contact ring 6 carries contact plates so disposed that either the lamp or the filament may be switched on by appropriately rotating the device upon the battery container.