Abstract: A hydraulic fluid control system regulates the delivery rate of feed water to a boiler. A hydraulic actuated diaphragm pump having a plurality of diaphragm working chambers which are interconnected with check valve controlled inlets and outlets pumps the feed water to the boiler. Fluid surges or pulsations are prevented by the use of projection members on the face of the diaphragms and by a variably controlled pressure regulator responsive to the feed water pressure. The delivery rate of hydraulic fluid to the diaphragms controls the actual pumping output. A bypass line including a pressure regulating valve with pilot control and a modulating control valve controls a bypass hydraulic fluid rate which directly corresponds to the pumping output rate.

Abstract: An apparatus for analyzing the performance of wheeled, land vehicle brake systems is described wherein means are provided for driving the vehicle wheels at a predetermined speed and the operator or computer controlled brake actuator selectively applies the brakes in a series of simple successive steps comprising the test sequence. The pedal force, or other actuating force, the brake effort exerted by each wheel, and the imbalance between the braking effort of opposite wheels is measured and recorded on a strip chart or fed to a computer, to determine if the measured values fall outside of a predetermined range of values representing acceptable deviations from standard values. Any deviation of the brake effort from the acceptable values, or excessive imbalance between opposite wheels at any point in the test sequence, may be used as a basis for diagnosing and identifying a specific brake malfunction. The system can be enlarged to simultaneously test the brakes on all wheels of a land vehicle.

Abstract: A roller type brake testing device is disclosed which incudes two pairs of cradling rollers for supporting and applying a driving torque to two wheels of a vehicle such as an automobile. The testing device includes a pneumatic lift mechanism for selectively raising and lowering the rollers which engage the rear portion of the wheels and through which driving torque is applied to the wheels. The brake tester may further include an indicator such as a pressure gauge for displaying a measure of the weight of the axle supporting the vehicle wheels to guide the operator in applying the brakes to achieve a braking effort correlated with axle weight.