William F. Davis - Tempe AZ Ronald W. Russell - Sunnyvale CA Thomas M. Frederiksen - San Jose CA Ernest L. Long - San Jose CA
Assignee:
Motorola, Inc. - DE
International Classification:
F02D 500 H01F 718
US Classification:
361154
Abstract:
A system for energizing an inductive load includes a voltage regulator for providing a constant voltage across the load until the current builds up to a particular value, and a current regulator which then takes over to provide a constant holding current at a lower value. The voltage regulator may include a closed loop for holding the voltage across the inductive load constant or may respond to a regulated voltage value to control a power stage for providing a constant voltage. The voltage across a sensing resistor in the power stage controls the crossover from the voltage regulation mode, to the current regulation mode and the current regulator automatically resets the reference to control the power stage to provide a constant current of a lower value through the load. The system can be used to supply current to coils of injector valves in a fuel injection system, and may include two power stages for supplying current to two banks of coils. The regulator system is switched from one power stage to the other during successive 180. degree.
Ernest L. Long - San Jose CA William S. Duvall - Portola Valley CA Donald P. Allen - Menlo Park CA
Assignee:
Amtel Systems Corporation - Sunnyvale CA
International Classification:
H04L 1534 H04Q 900
US Classification:
34082555
Abstract:
A message communication system which provides instant messages and memoranda at a telephone user's desk. In an office complex, a message is transmitted over pre-existing office power lines to printers located in a user's office and is automatically posted with time of day, date and sequence number. When a telephone call cannot be completed, messages are entered at the terminal by a telephone operator or message attendant. A computer automatically formats message forms and stores the text on a magnetic diskette. Messages are transmitted to outlying printers and can be recalled for display or resending at any time.