The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 22, 1980
Filed:
May. 09, 1978
Neil H Jagoda, Framingham, MA (US);
John S Ballas, Newton, MA (US);
Klaus Kubierschky, North Reading, MA (US);
American Science & Engineering, Inc., Cambridge, MA (US);
Abstract
A remote load controlling apparatus receives a disconnect signal on a line that is filtered and voltage limited. This disconnect signal sets a flip-flop which enables an oscillator and a solid-state switch. The enabled switch energizes a relay to disconnect the load from electric service. A counter counts the output of the enabled oscillator and provides a flip-flop reset signal after a local time delay that is determined by a particular incremented count state of the counter. The reset flip-flop disables the oscillator and solid-state switch to de-energize the relay and reconnect the load to electric service. The flip-flop may also be reset by a remote signal to disable the oscillator and solid-state switch and reconnect the load before the counter is incremented to its particular incremented count state. A second counter and a second solid-state switch may be added to ensure that the load is connected to electric service if a component of the apparatus should fail. The second solid-state switch is enabled by the pulse output of the enabled oscillator and is disabled when the oscillator stops generating pulses. The second solid-state switch is connected in series to the first solid-state switch and the relay is energized only when both solid-state switches are enabled. The second counter is provided to enable the oscillator on the leading edge of the disconnect signal and disable the oscillator after a time delay.