Printer carriage acceleration control device

A carriage control device having a PWM control unit controlling the current supplied to a printer carriage motor to bring a revolution speed of the printer carriage motor close to a selected standard speed, comprising:

• means for generating selectively one of a plurality of standard speeds;
• means for generating predetermined current limiting values corresponding to respective ones of the selectively generated standard speeds,
• the current limiting values corresponding to successive ones of said standard speeds of increasing speed being either of equal or increasing amplitude;
• means for detecting the current supplied to said carriage motor;
• and
• means for limiting the current supplied to said motor while the motor is being driven at a selected one of said standard speeds so that a detected value of the current does not exceed the generated current limiting value corresponding to said one selected speed.

A device for controlling the revolution speed of a printer carriage motor, comprising:

• means for detecting revolution speed of a carriage motor and generating a revolution speed signal in response thereto;
• means for generating a standard speed signal corresponding to a standard revolution speed;
• means for integrating a difference between the revolution speed signal and the standard speed signal;
• means, responsive to an output value of said integration means, for generating a first control signal for controlling the revolution speed to correspond to said standard speed;
• means for selecting either one of said first control signal and a second control signal;
• means for driving said carriage motor according to one of said first and second control signals selected by said selecting means;
• means, in response to an initiating signal, for causing said selecting means to select said first control signal for accelerating said motor speed from zero speed to a condition where the motor speed corresponds to said standard speed and is being regulated at said standard speed in response to a first output value of said integration means;
• means for detecting said first output value and for storing it as an optimum integration value;
• said second control signal being effective, independently of said integration means, for accelerating said motor from zero speed towards said standard speed at a rate more rapid than the acceleration of said motor in response to said first control signal;
• means, in response to an operating signal, for causing said selecting means to select said second control signal for causing acceleration of said motor from zero speed to a predetermined transfer speed less than said standard speed and for thereafter selecting said first control signal for continuing the acceleration of said motor to said standard speed in response to output values of said integration means;
• and
• means for loading the stored optimum integration value into said integration means and for causing the output value of said integration means to be said optimum integration value when said first control signal is selected in response to said motor reaching said predetermined speed.