Electromechanical trigger for alarm clocks and other timer-operated signal emitters

US4443113A · kind A · utility

Assignee

• Kieninger & Obergfell GmbH & Co. · DE

Inventors

• Wolfgang Fehrenbacher · St. Georgen, DE
• Hans Heinzelmann · Schramberg, DE
• Erich Scheer · St. Georgen, DE

Key dates

• Filing date: Apr 27, 1981
• Grant date: Apr 17, 1984
• Expiry date: Apr 27, 2001

Classification

• Technology area (CPC G): Physics
• CPC primary: G04C21/16
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An alarm clock has a cambered leaf spring traversed by a nest of clock-hand shafts projecting from a mounting plate designed as a printed-circuit board. The leaf spring is supported at opposite ends by posts rising from the mounting plate and is limitedly swingable about a centerline parallel to that plate and perpendicular to the axis of the nested shafts. A toothed control disk centered on the same axis, with a hub carrying an alarm hand, is axially shiftable under pressure of the cambered leaf spring upon alignment of a tooth on that disk with a notch in an adjoining hour wheel; two diametrically opposite metallic contacts formed by lateral tongues on that spring then engage respective countercontacts on the mounting plate to close a circuit for the emission of an acoustic alarm signal. The alarm circuit can be broken by a manually displaceable interrupter lifting one of these tongues off its countercontact; with a modified alarm circuit, closure of one or the other contact pair can be selectively inhibited to enable the alternative operation of a buzzer or of a radio receiver upon displacement of the control disk by the leaf spring.