Vacant-seat detector for theaters.

摘要: 126,129. Johnson, J. B., and Burns, E. S. May 1, 1918. " Engaged like indicators. - A vacant-seat indicator for theatres &c. comprises a board depicting plan of the theatre, seats being represented by apertures provided with closures, closed thereby, or open, according to whether corresponding is occupied vacant. The are pivoted control electrically. may be illuminated from behind. As shown, B circular, closures C in form disks mounted on spindles. closure held position leaf spring (not shown), bearing against flat formed projections spindle. spindle also carries bar magnet 31 within fixed coil 30. When energized, axis magnets sets itself more less parallel coil, aperture open. de-energized, leaf-spring holds its at right-angles closed. G (two shown) depressed weight occupier, operate switch devices each comprising casing 35 contact 41, movable 39 carried plunger 38 which raised, when seat vacant, 40, so as close contacts 39, 41. numbers aisles marked luminous paint.