Magnetostrictive pump with reversible valves

Abstract

A hydraulic pump having a cylinder closed at one end with an elongated piston arranged within the cylinder from the other end. The piston is constructed of a positive magnetostrictive material which increases in length in the presence of a magnetic field of appropriate intensity. It is wound along its length with a coil of wire capable of producing an electro-magnetic field upon energization. The piston is fastened at the open end of the cylinder to define a cylinder cavity between the cylinder closed end and the piston. A pair of passages including valves, for use as an intake and an exhaust passage, communicate with this cavity. The valve members in each cavity comprise a magnetically polarized member, each of opposed polarity as related to the other, such that upon energization of the pump with one polarity of pulses, the valves will assume a particular function, and with a reversed polarity of operating pulses, a reverse function. The volume of this cavity is reduced when the piston expands under the influence of the magnetic field created by the coil to produce a pressure on any fluid contained within said cavity to force it out the exhaust passage. In a preferred embodiment the cylinder is constructed of a negative magnetostrictive material which contracts or shrinks in length in the presence of magnetic field.