Worldtronics International, Inc.

Gerald C Koehler

Anthony W Rigazio

A hybrid analog and electronic cycle timer has a mechanical movement and cam-operated cycle switch driven by a low-RPM synchronous motor. Electronic control logic divides the power line frequency to obtain pulses for pulsing the synchronous motor. The control logic also includes an activation interval timer and a lockout flip-flop which inhibits the activation interval timer. The activation interval timer is otherwise triggered by closure of the cycle switch. The lockout flip-flop is set after a power failure and at the end of the activation interval, and is reset by a manual reset signal. The activation interval timer may include an activation enable flip-flop and an activation interval counter. The state of the control circuit is conveniently indicated by an indicator which is activated continuously during the activation interval, and which is activated intermittently when the activation interval timer is inhibited by the lockout flip-flop. The control logic is preferably included in a single CMOS integrated circuit.

Cycle timer for household appliance

An electrical timer for a household appliance typically has an integrated circuit including an internal presettable clock registering the time of day, an internal register storing a presettable activation time, and a gate generating an activation signal when an activation enable signal is present and the clock registers the activation time. To prevent an activation signal from being generated on a daily basis without manual intervention, a bistable circuit is provided to generate the activation enable signal in response to a cycle enable signal received from the appliance operator. The bistable circuit is set to activate the activation enable signal upon receipt of the cycle enable signal, and is reset by the activation enable signal to disable the activation enable signal. For a coffee maker, the bistable circuit is preferably reset by the activation signal at the active-to-inactive transition signalling the end of brewing. To reject electrical noise pulses, the bistable circuit preferably has a response time of at least approximately five milliseconds. Preferably the cycle enable signal is generated by a three position switch having 'on' and 'off' positions which activate and deactivate the activation signal regardless of the time of day, and a middle 'automatic' position. In this case the bistable circuit is set when the switch is moved from the automatic position to the off position. Alternatively a separate push-button switch generates the cycle enable signal.

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Peru, IL, United States of America

Gerald C Koehler