US 4,234,830 A · Stepping motor control circuit

Abstract

Disclosed is a stepping motor control utilizing a microprocessor. The control is suitable for driving one or more stepping motors one at a time or in unison. In the illustrated embodiment when plural motors are driven together they are driven at the same rate or at rates in a fixed proportion to one another although several of the features of the invention are suitable for use in circuits providing contouring control; i.e., where separate motors are driven at separate stepping rates proportional to the relative distances each is to traverse for a single movement. An acceleration/deceleration circuit is utilized which provides simple yet highly accurate and efficient control of the stepping motors. Feed rate compensation for simultaneous drive of two motors is provided. Also a means is provided to allow stepping rates in excess of the counting rate capability of the microprocessor.

Claims4

Dependent claims

In a numerical controller for controlling the movement of a part of the action of two stepping motors moving in response to pulses, a control circuit comprising:

(a) oscillator means providing pulses at a rate proportional to the rate of desired movement of the part;
(b) drive means controlled by pulses from said oscillator means to drive said stepping motors both simultaneously and individually at a rate proportional to the rate it receives pulses;
(c) means to determine when said stepping motors are to be driven simultaneously;
(d) means for blocking pulses to one of said stepper motors when it is determined that both will not be driven simultaneously;
and
(e) means interposed between said oscillator means and said drive means to reduce the rate of control pulses to said stepping motors by a factor of approximately 1.4 when both of said stepping motors are being driven simultaneously as compared to when they are driven individually.

3 more elements

Dependencies are inferred from the claim text.

Stepping motor control circuit

Life of this patent

Stepping motor control circuit

Life of this patent

Abstract

Claims4