| 摘要 |
<p>1,078,533. Fluid regulation. BOWLES ENGINEERING CORPORATION. July 6, 1964 [July 5, 1963], No. 55766/66. Divided out of 1, 078, 531. Heading G3H. [Also in Division F1] A fluid control system includes a low pass filter comprising two parallel tapered passages 31, 32, Fig. 1 (not shown) connected by a series of narrow cross-over passages (33) in the form of a ladder. The parallel passages taper to a size equal to the cross-over passages and the wider end constitute the inlet and outlet of the filter. A pulsed fluid flow is fed through the filter and at low frequencies the pressure drop in the cross-over passages is small and the flow is passed through the filter. At high frequencies the cross-over passage effect a large pressure drop and then the high frequency signals are greatly attenuated. The tapering of the inlet passage minimizes reflections of the high frequencies. This RL ladder arrangement also acts as a sonic filter in that a single narrow passage while filtering the high frequency pressure signals rings at frequencies above the tuned frequency and the cross-over channels are effective to break up the wave front as the signal passes between the tapered passages. The filter may also include a capacitance thus forming an RLC filter. The filter is used in the control system described in Specification 1, 078, 531.</p> |
