GB349183A - Improvements in audible traffic signal or warning devices - Google Patents

Abstract

349,183. Sound-producing devices. MOTO METER GAUGE & EQUIPMENT CORPORATION, Long Island City, New York, U.S.A. March 13, 1930, No. 8187. Convention date, March 18, 1929. [Class 40 (iv).] A traffic signal device comprises vibration-producing means supported behind a cover-plate 43 having apertures therein for the forward emission of sound, and in front of a back cover-plate 44 having a flange spaced from the front plate to form a passage for sounds deflected by the back plate. The vibration-producing means may comprise diaphragms 1, 2 riveted together at their flanged peripheries and actuated by an electromagnet comprising a core 6, and coil 9 mounted in a cup-shaped core member 11 and clamped to the diaphragm 2. The front diaphragm 1 carries an armature plate 13, spacer plate 14, resonator 15, and counterbalancing plate 16 held together by rivets 17, the weights on both diaphragms 1, 2 being equal. Contact strips 19, connected to terminal posts 21 outside the casing, are adapted to follow the movements of contact members 33 carried by an insulating strip connected to the core member 11 and maintain circuit until stopped by an adjustable abutment 34 to break circuit. The abutment 34 is held in position by a member 41 connected to an adjusting screw 38 which adjusts the air gap between the armature 13 and the electromagnet and is locked in position by a lock-nut 40. The cover-plates 43, 44 are held by bolts 47 with locknuts 51 which, by spacing sleeves 48, 49, clamp the diaphragm structure in position. Specification 301,740, [Class 40 (iv), Telephones &c.], is referred to.