Step motor acceleration-deceleration control system

Claim 1

A step motor control system for controlling a step motor or the like, said system comprising pulse supply means for supplying a train of control pulses to a step motor; and pulse control means connected between said pulse supply means and said step motor for gradually increasing the frequency of pulses in the beginning of said pulse train and gradually decreasing the frequency of pulses in the end of said pulse train thereby enabling proper starting and stopping of said motor when said motor operates at high speed, said pulse control means comprising reversible counter means having inputs and outputs for storing the control pulses supplied thereto, input means for supplying said train of control pulses to an input of said reversible counter means for storage therein, variable frequency oscillator means coupled to an output of said reversible counter means for providing pulses having a frequency proportional to the content of said reversible counter means, output means, AND gate means having an input connected to said variable frequency oscillator means for receiving said pulses from said variable frequency oscillator means, an input connected to said reversible counter means for receiving a nonzero signal from said reversible counter means and an output connected to said output means, and feedback means connected between said output means and said reversible counter means for transferring pulses to said reversible counter means as negative feedback pulses in a manner whereby each feedback pulse subtracts from the content of said reversible counter means.