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US 4,362,399 AGranted
Circuit for an electronic clock having a parallel-connected alarm device and stepper motor
AssigneeU.S. Philips Corporation
InventorFranz Fick
Life of this patent
Estimating the term…
Abstract
In an electronic clock circuit having both a stepper motor and a PXE (piezoelectric oxide) alarm element, the stepper motor and PXE element are connected in parallel and appropriate motor and PXE drive signals are provided on the same line. With this circuit configuration, an inductance and a transistor are eliminated from the prior art circuit, thus resulting in a smaller and less expensive device.
Claims2
A circuit for an electronic clock having display elements and an alarm device, which comprises:
- a quartz oscillator;
- a stepper motor for driving the display elements;
- a PXE alarm element connected in parallel with said stepper motor;
- a frequency divider having its input coupled to said quartz oscillator and its output coupled to the parallel combination of said stepper motor and said alarm element;
- and
- means for switching the output frequency of said divider from a first frequency for providing stepping pulses to said motor to a second frequency for driving said parallel-connected PXE element during the time interval between said stepping pulses.
3 more elements
Dependencies are inferred from the claim text.