Multistage Hydraulic Summing and Signal Processing Amplifiers and Fluidic Input Servovalve Development.

摘要

The development of fluidic summing and dynamic signal compensation operational amplifiers for high performance hydraulic systems is described. The amplifiers are constructed from three stage fluid amplifiers using as input and feedback elements linear resistors constructed from small diameter to length ratio tubing and capacitors constructed from flexible metal diaphragms. The summing amplifier has a pressure gain of 50 and a frequency response which is flat to 100 Hz. Dynamic compensation elements were constructed with lead-lag action where the lead action dominates in the 20 to 40 Hz range. A four-way fluidic input servovalve has been developed. The valve consists of a fluid amplifier driving a pair of bellows that act directly on the flapper of the first stage flapper-nozzle valve, and a second stage spool valve whose position is controlled by the output of the first stage valve. The valve accepts pressure inputs in the 0 to 7 kPa range and has a frequency response which has decreased by 3 dB at 30 Hz. (Author)