Sewing machine having a memory for generating a speed signal in response to operating conditions

摘要

Disclosed is a sewing machine having a tachogenerator for generating pulses at a frequency proportional to the speed of the sewing machine and a position detector for detecting the position of a foot pedal. A sewing condition detector is provided for detecting the operating conditions of the sewing machine in which it is to be subsequently operated and generating therefrom a corresponding condition indicating signal and a manually adjustable binary code generator for generating a speed indicating binary code in response to the condition indicating signal. Further included is a digital memory responsive to the position indicating signal and the speed indicating binary code for generating a speed control digital signal. The pulses generated by the tachogenerator are processed in accordance with the speed control digital signal to control the amount of motive power transmitted from a motor to the sewing machine.