WITH USE OF SELF REGULATING CONTROL SYSTEM UTILIZINGELECTRICAL OR HYDRAULIC ENERGY:
(under the class definition) Subject matter comprising apparatus including, or method employing, at least two devices that deform work, each device being driven or governed by a motor powered either by fluid under pressure or by electricity, but in either case from a source of power common to all the motors, wherein the operation of one such motor is regulated or modified by a change (including an incipient change) in the power demand or operating condition of another such motor, thereby changing (or tending to change) the ratio of power supplied to each motor.
(1) Note. Compare the subject matter of this and the indented subclasses (28.1+) with that of subclasses 13.1+ and 19.8+. In a device of this subclass, back pressure (in a hydraulic motor) or back electromotive force (in an electrical motor) as the agency to govern the operation of another such motor, whereas a device or subclasses 13.1+ and 19.8+, clearly teaches use of a detecting means to sense a condition.
