(under subclass 7) Apparatus in which the rate of movement of the power means varies with the magnitude of the sensed force in such a manner that the rate of movement increases or decreases when the magnitude of the sensed force increases or decreases respectively.
(1) Note. This subclass includes, for example, those devices in which a plurality of pumps, a variable capacity pump, or a plurality of successively operated valves are used to operate a fluid servomotor.
(2) Note. A system which has a mere single valve for directing fluid to a servomotor which would provide less restriction to fluid flow upon greater opening of the valve in response to the increased magnitude of the sensed force is not included in this subclass.
