Improvements in sound control for hooters sounding several notes

摘要

384,483. Multi-note warning horns. SPEZIAL -WERKZEUGFABRIK-FEUERBACH GES., Feuerbach, Stuttgart, Germany. Feb. 19, 1932, No. 5005. Convention-date, March 28, 1931. [Classes 13 and 88 (i).] The individual diaphragms 4 of warning horns adapted to sound several notes are operated by compressed air supplied from a compressor driven by an electric motor 14 and are prevented from freely vibrating by means of a locking device arranged so that the diaphragms may be released either singly or jointly by hand or by electromagnets 7, 72, 71, so that a single note or a chord is sounded. In one form, as operated electromagnetically, closure of a switch 13 starts the motor 14, which rotates through worm gearing 16, 17 a drum 19 having surface contact segments 21, 22, 23 connected to a ring 20. Wipers 25, 26, 27 contact with the segments during rotation of the drum 19 and energize the magnets from current supplied through a wiper 24 contacting with the ring 20. Closure of a switch 28 simultaneously with the switch 13 energizes a magnet 29 causing a contact plate 30 to interconnect the wipers 25, 26, 27, energize the magnets 7, 72, 71, and cause the horns to be operated simultaneously. The locking devices are each formed of a block of felt 9 carried in a spring-controlled armature 8 of each electromagnet. When hand operated, a pull wire under control of the vehicle driver is connected to the armature 8.