Approaches and Trends in Automatic Speed Controls

This paper reviews automatic speed control progress covering the earlier buzzers and throttle holders and explores the operation and function of the true speed control which automatically operates the throttle to maintain a preset car speed under varying conditions of wind, grade, and load.

The basic anatomy of the automatic speed control, which consists of the manual control system, the car speed sensor, the “brain,” the power unit, and the disengagers is described. Automatic relatch and resume-speed features are also treated, as are accuracy, safety, and fuel economy aspects of these devices. Discussion of recent trends in low cost vacuum controls with simplfied button operation completes the paper.