Coil and coil driver control apparatus

Claim 2

In an apparatus (10) having a plurality of controllable contactors, each contactor having an associated coil (14A-E) and coil driver (16A-E), and means (18) for selectively supplying respective control signals to controllably energize and deenergize each of said coil drivers (16A-E), the improvement comprising: monitoring means (84) for sensing the total current flowing through said plurality of coils (14A-E) and supplying a variable current signal in response to the magnitude of said sensed total current; and control means (85) for receiving said current signal and controllably limiting the number of concurrently energized coils (14A-E) to a preselected maximum number in response to the magnitude of said current signal.

Claim 3

An apparatus (10), as set forth in claim 1, wherein said control means (85) includes means (87) for supplying a triggering signal in response to the magnitude of said current signal exceeding a preselected value.

Claim 4

An apparatus (10), as set forth in claim 2, including means (99) for receiving said triggering signal and supplying a blocking signal in response to receiving said triggering signal, said blocking signal having a preselected duration.

Claim 5

An apparatus (10), as set forth in claim 3, including limiting means (89) for receiving said control signals and said blocking signals, passing said control signals to respective coil drivers (16A-E) in response to receiving said control signals in the absence of said blocking signal, and blocking each of said control signals from said coil drivers (16A-E) in response to receiving said blocking signal.

Claim 8

An apparatus (10), as set forth in claim 5, wherein said blocking signal is a pulse having a preselected time duration.

Claim 9

An apparatus (10), as set forth in claim 5, wherein said monitoring means (84) includes a current shunt (94, 94') connected in series with each of said coils (14A-E) and respective coil drivers (16A-E).

Claim 10

An apparatus (10), as set forth in claim 5, wherein said limiting means (89) includes a plurality of logic gates (86A-E), each having a first input connected to receive said blocking signal, a second input connected to receive respective control signals, and an output connected to deliver said control signals to respective coil drivers (16A-E).

Claim 13

Apparatus (10) for controlling a plurality of contactors, each contactor having an associated coil (14A-E) connected to a power source, comprising: means (18) for controllably supplying a plurality of respective contactor control signals; a plurality of driver transistors (92A-E), each having a collector terminal connected to a respective one of said coils (14A-E), an emitter terminal connected in common with at least one other of said driver transistor emitter terminals, and a base terminal; a plurality of shunt resistors (94, 94'), each having a first terminal connected to a respective set of commonly connected emitter terminals, and a second terminal connected to apparatus ground; a plurality of triggering transistors (96, 96'), each having a respective base connected to one of said shunt resistor first terminals, an emitter connected to apparatus ground, and a collector connected to said power source; a mono-stable multivibrator (100) having an input terminal connected to each of said triggering transistor collector terminals, and an output terminal; and, a plurality of logic gates (86A-E), each having a first input terminal connected to said multivibrator output terminal, a second input terminal connected to said supplying means 18, and an output terminal connected to a respective one of said driver transistor base terminals.

Claim 14

Apparatus (10) for controlling a plurality of contactors, each contactor having an associated coil (14A-E) connected to a power source, comprising: means (18) for controllably supplying a plurality of respective contactor control signals; a plurality of driver transistors (92A-E), each having a collector terminal connected to a respective one of said coils (14A-E), an emitter terminal connected in common with at least one other of said driver transistor emitter terminals, and a base terminal; a plurality of shunt resistors (94, 94'), each having a first terminal connected to a respective set of commonly connected emitter terminals, and a second terminal connected to apparatus ground; a plurality of triggering transistors (96, 96'), each having a respective base connected to one of said shunt resistor first terminals, an emitter connected to apparatus ground, and a collector connected to said power source; a mono-stable multivibrator (100) having an input terminal connected to each of said triggering transistor collector terminals, and an output terminal; and, a plurality of logic gates (86A-E), each having a first input terminal connected to said multivibrator output terminal, a second input terminal connected to said supplying means 18, and an output terminal connected to a respective one of said driver transistor base terminals.