| 摘要 |
1,266,211. Fluid-pressure servomotor system; fluidic element. FOXBORO CO. Oct.22, 1969 [Nov. 1, 1968], No. 51774/69. Headings G3H and G3P. A fluidic element comprises a lamina 11A resiliently fulcrummed at 14 to provide isolated chambers 18-21 connectable into a fluidic system by connectors 26-29, and a vented orifice 24 which acts with lamina 11A to form a flapper valve. The lamina is of metal, glass or plastics material backed by a layer 15 of resilient material, and has horse-shoe slots 12, 13 which permit it to flex about fulcrum 14. In various modifications (not shown) a pair of laminations sandwich the resilient layer, or the resilient layer is dispensed with and the slots 12, 13 are either sealed with mercury or left open. In another modification, Fig. 8 (not shown) the lamina only defines chambers 18, 20 whilst a portion extending outside the capsule cooperates with nozzle 24, Fig. 4 (not shown) illustrates an arrangement in which the movable area of the lamina is reduced to the width of supports 16A, 17A. Fluid-pressure servomotor systems:- The element is used to operate a process controller 30, Fig. 7, by producing a pressure in line 32 which is determined by the difference in pressure between a process measurement signal in line 31 and the set point signal generated at 33. This differential pressure moves lamina 11A to control the flow through orifice 24 so that the pressure in chamber 21 returns the lamina to its datum position. This pressure is fed by lines 36, 38 to control valve 40 which resets the pressure in line 32. |
