GB150350A - Improvements in electrically actuated gongs and like sound producing apparatus - Google Patents

Abstract

150,350. Magerle, E. Feb. 24, 1919, [Convention date]. Bell-operating mechanism, electric.-Relates to electric bells and like sound-producing apparatus in which a hammer or tapper is actuated by a solenoid which co-acts with a resilient contact to make and break the circuit. The solenoid plunger 2, of magnetic material, is in electrical contact with a metal guiding sleeve 9 on which the solenoid coil 1 is wound, and rests on a resilient contact 7. On making the circuit, the current flows through contact 7, plunger 2, sleeve 9, and through the coil 1, thus attracting the plunger 2 up the coil and breaking the circuit at contact 7, the period elapsing before contact is broken, and consequently the quality of the stroke, depending on the nature of the contact spring 6. The hammer head 4, of non-magnetic material, for example wood, may be mounted on an adjustable rod 3, or may be spaced from the plunger by a spring, or it may have a rod 3, Fig. 6, which slides in a hollow plunger and is spaced therein by a spring 19 from a similarly sliding stud 16, which engages between two springy contact strips 21, 22. For slow beat bells a plunger shaped as at 2, Fig. 2. without the head 4 and rod 3, may function as the hammer. The striking appliance may all be located within the gong 8, or may be outside and strike on two gongs, the contact beneath the plunger being shown in this case as telescopic members pressed apart by a helical spring. The Specification as open to inspection under Sect. 91 (3) (a) comprises also a bell push for causing a solenoid-operated bell to make two strokes only, the solenoid in this case not requiring a contact 7, and a flange being provided to prevent the plunger 2 falling down to touch the gong. The push is fitted with a rocker 32, Fig. 9 (Cancelled), through which the circuit is completed when first touched by a push spring 31, but when further pressure is applied to the push the circuit is broken by one rocker arm being raised off the contact plate 34. A similar sequence occurs when pressure is taken off the push; thus' two waves of current are sent through the solenoid, giving two strokes on the gong. This subjectmatter does not appear in the Specification as accepted.