Control system for a plurality of stepper motors

Claim 3

The system as defined in claim 1 further including incremental means for generating an alignment signal to an associated one of said drive signal means, said alignment signal stepping each associated one of said stepper motors a predetermined amount.

Claim 4

The system as defined in claim 1 further including means for selectively enabling or disabling each of said drive signal means.

Claim 5

The system as defined in claim 3 wherein said enabling/disabling means comprises a power on/off switch coupled to an associated one of said drive signal means.

Claim 6

The system as defined in claim 1 wherein said control means comprises a microprocessor.

Claim 7

A machining/positioning apparatus for controlled execution of a plurality of substantially identical machining and/or positioning tasks, using a plurality of selected indexers, comprising: input means for providing program signals responsive to an input; control means responsive to said program signals for generating control signals; a plurality of drive signal means responsive to said control signals for generating electrical drive signals, said control means coupled to a first one of said plurality of drive signal means and additional ones of said drive signal means, enabling input of substantially the same said control signal to each of said plurality of drive signal means; motor means responsive to said electrical drive signal for generating powered movement to perform said machining and/or positioning; and indexer means responsive to said powered movement for effecting a measurable selected spatial movement during said machining and/or positioning.

Claim 8

A machining/positioning apparatus for controlled execution of a plurality of substantially identical machining and/or positioning tasks, using a plurality of selected indexers, comprising: input means for providing program signals responsive to an input; control means responsive to said program signals for generating control signals; a plurality of drive signal means responsive to said control signals for generating electrical drive signals, said control means coupled to a first one of said plurality of drive signal means and additional ones of said drive signal means, enabling input of substantially the same said control signal to each of said plurality of drive signal means; motor means responsive to said electrical drive signal for generating powered movement to perform said machining and/or positioning; and indexer means responsive to said powered movement for effecting a measurable selected spatial movement during said machining and/or positioning.

Claim 11

The system as defined in claim 1 wherein said control means and said drive signal means are adapted for portable use.

Claim 12

A power drive unit for providing electrical drive signals to a stepper motor responsive to control signals from a programmable controller, comprising: means responsive to said reduced current level control signals for limiting the current level of said drive signals during the acceleration and deceleration of said stepper motor; and holding torque current means for providing a holding torque current to keep said stepper motor at the angular position associated with said control signals from said programmable controller upon decelerating said stepper motor to stop at the angular position associated with said drive signals.

Claim 13

A power drive unit for providing electrical drive signals to a stepper motor responsive to control signals from a programmable controller, comprising: means responsive to said reduced current level control signals for limiting the current level of said drive signals during the acceleration and deceleration of said stepper motor; and holding torque current means for providing a holding torque current to keep said stepper motor at the angular position associated with said control signals from said programmable controller upon decelerating said stepper motor to stop at the angular position associated with said drive signals.

Claim 14

The power drive unit as defined in claim 9 wherein said optoisolator circuit means comprises an optoisolator and a coupled predetermined resistance.

Claim 15

The power drive unit as defined in claim 9 wherein said means for limiting the current level of said drive signals comprises a power transistor circuit.

Claim 16

The power drive unit as defined in claim 9 wherein said holding torque current means comprises means responsive to sensing said reduced current level control signals for actuating a high voltage switch and a constant current circuit source means for providing a holding current responsive to deactivation of said high voltage switch.

Claim 17

The power drive unit as defined in claim 12 wherein said constant current circuit source means comprises a constant current source and a diode.

Claim 20

The system as defined in claim 14 wherein said plurality of selectable positions includes two least significant bits adapted for repeated sequential addressing between binary zero and binary three as said switch is rotated in one direction.

Claim 21

The system as defined in claim 14 wherein the first significant binary bit of said binary coded switch undergoes a change of state between each position of said switch, detection of said change of state enabling rejection of improper data present during the turning of said switch from one position to the next.

Claim 22

The system as defined in claim 9 further including incremental means for generating an alignment signal to an asssociated one of said drive signal means, said alignment signal stepping each associated one of said stepper motors a predetermined amount, said incremental means in communication with said optoisolator circuit means.

Claim 23

The system as defined in claim 14 wherein said incremental means further comprises a memory element associated with each of the windings of said stepper motors, each said memory element initialized responsive to said control signals and the data within each said memory element being output by a data selector responsive to address bits from said binary coded switch.

Claim 24

The system as defined in claim 18 wherein said memory element comprises a shift register.

Claim 25

The system as defined in claim 1 wherein said drive signal means is adapted to operate using low electrical levels for said control signals, enabling the driving of a large number of said drive signal means.