GB1217225A - Improvements in or relating to electrically operated valves and fluid-flow directing devices - Google Patents

Abstract

1,217,225. 225. Fluid regulation; servovalve. AUTOMOTIVE PRODUCTS CO Ltd. March 27, 1969 [May 23, 1968] No.24710/68. Headings G3H, G3P. [Also in Division F2]. A fluid-flow control or flow directioning device, comprises a chamber 10, an inlet passage 11, 13 which is restricted at 14, a utilization devicesupplying passage 15, a vent passage 12, and a Piezo-electric unit 16 which extends within the chamber and from that end wall thereof which is opposite to that incorporating the inlet passage, the unit being connected to voltage source 21 and carrying at its free end an obturator 17. In the de-energized state of the unit, the obturator end face 18 is disposed a very small distance from the adjacent chamber end wall such that substantially all flow takes place through passage 15. When energized, the unit bends sideways and so reduces the restriction of flow between the inlet and vent passages. In a modification, Figs. 2 and 3 (not shown), the inlet and supply passages open into the chamber end wall, the inlet passage being centrally disposed, and the obturator has formed on its underside a groove which in the de-energized state of the unit extends across the inlet only. In a still further modification, Fig. 4 (not shown), the unit carries a supply pipe and the chamber end wall has formed therein two mutually-inclined outlet passages, deflection of the unit resulting in either one of the two passages being placed in direct communication with the supply pipe.