Abstract: A flow control valve comprises a valve body with a central flow passage containing a poppet releasably engagable with an annular valve seat, the poppet comprising a poppet head engageable with the valve seat and a central bore filled with an expansion member formed of silicone rubber or other substance having a coefficient of thermal expansion different from the material of the valve body and the poppet bore being closed by a stop member fixed in position relative to the valve seat, whereby the expansion or contraction of the expansion member causes the poppet head to move toward or away from the valve seat, increasing or decreasing flow through the valve. A spring adjustably pre-compresses the expansion member and balances the force created by the expansion of the expansion member, the axial position of the stop member being adjustable.

Abstract: A method for providing resistance to flow through a flow passageway comprises partially blocking flow through an orifice of reduced diameter by masking the orifice with an element formed of porous material retained immediately adjacent to every side of the orifice that is expected to be exposed to higher pressure fluid with a greater surface area of the porous masking element being exposed to fluid in the passageway on the higher pressure side of the orifice than is exposed by the orifice to the lower pressure fluid. The orifice may be formed by direct configuration of the passageway walls or by a body adapted to retain the masking element in the body, the outside of the body being adapted to for secure installation within the flow passageway. Resistors in accordance with the present method may have masking elements on one side for use with one directional pressure differentials or masking elements on both sides for use in applications in which bidirectional pressure differentials are anticipated.

Abstract: A fluid resistor for providing resistance to flow through a flow passageway is formed by cutting channels and open cylindrical recesses on the surface of and flow passage bores through a frusta-conical body to be seated in a tapered passageway section with the larger diameter end generally subject to higher system pressures than the smaller diameter end. The seating of the resistor body in a tapered passageway section seals and encloses the channels and recesses which then with the fluid passageways through the resistor body, comprise a restricted path for flow to proceed past the installed resistor, the recesses forming cylindrical chambers.

Abstract: An expansion sealing plug having a frusto-conical plug body with peripheral U-shaped grooves, an expansion member comprising either an inner wedge pin or a spherical member, and a tapered coaxial bore for receiving the expansion member. The inner wedge pin has a greater average outside diameter and the spherical member has a greater maximum outside diameter than the tapered coaxial bore. The plug body and expansion member are proportioned to be readily preassembled such that the expansion member is frictionally retained after partial insertion into the plug body. The unexpanded plug is inserted into a counterbore that is reamed or formed with the same taper angle as the plug body and the expansion member is driven axially into the plug such that the plug body is radially expanded to forcibly engage the counterbore.

Abstract: A device for removably retaining a fluid system component in a smooth bore comprises of body on one end of which the component is mounted and the other end of which comprises a plurality of wings. The interior of the body provides female screw threads into which an expansion member is engaged, said expansion member having male screw threads at one end and at the other end a truncated conical section. Rotation of the expansion member relative to the body causes further insertion for expansion member into the body such that the conical section causes the wing members to radially expand and engage the wall of the installation bore. The device is generally cylindrical in overall configuration with an outside diameter at least slightly less than the inside diameter of the installation bore and upon retraction of the expansion member from forcible engagement with the body, the wing members relax to their original state and the device can then be readily removed from the installation bore.

Abstract: A fluid control valve comprises a slidable, tubular poppet member that is biased toward and sealingly engages dual concentric annular valve seats, which valve seats define an annular opening through which the fluid medium flows when the valve is open. When the system pressure reaches a threshold pressure the poppet member is axially displaced from the valve seats such that an annular orifice is opened between the inside edge of the poppet and the inside valve seat and another orifice is formed between the outside edge of the poppet and the outside valve seat through which orifices the fluid medium flows into a central, axially extending relief path partially defined by the inside of the poppet. The dual orifices allow the valve to open with a stroke that is about one-half that of that required in a valve with only one orifice and similar operating range.

Abstract: A check valve that allows flow in one direction only and is suitable for controlling corrosive, chemically active or sensitive fluids comprises a body formed of a suitably inert substance defining inlet and outlet flow passages with a central chamber between the flow passages and an elastomeric disc traversing the central chamber. Centrally located disc stops bias the disc against an annular valve seat comprising a ridge surrounding the flow path and the sealing engagement of the disc and the valve seat prevents flow through the valve. An increase of the pressure differential across the disc sufficient to overcome the resilience of the disc causes the disc to deform whereby the perimeter of the disc lifts off the valve seat and allows flow through the valve. Support stops are provided at the inlet end of the central chamber to prevent the disc from being forced into the inlet flow passage upon exposure to a high back pressure differential.

Abstract: A self-retaining smooth bore insert employs a helical coil spring for retaining a fluid system component in a smooth bore. The spring comprises two connected helical coils. One coil is coiled around the component. The second coil has an engarged diameter which engages the wall of the smooth bore. An end portion of the second coil is engaged by an installation tool to contact the coil to permit installation.

Abstract: Three embodiments of a self-retaining fluid system component insert for a smooth bore of predetermined diameter. The insert comprises a helical coil spring with one end thereof connected to the component and having, in its relaxed state an outer diameter slightly greater than the bore diameter to frictionally lock the insert within the bore. The insert has a threaded connector for receiving an elongated tool for mounting the insert by rotating the insert in one angular direction thereof for contracting the coil by its frictional engagement with the smooth wall of the bore.

Abstract: A maximum pressure indicator for indicating maximum pressure of a fluid system employs a deformable disc which is bonded to a main plug. The plug has a cavity which is sealed by the disc so that a low pressure is maintained in the cavity. The indicator is inserted into an installation bore of a fluid system. The maximum pressure exerted against the disc is indicated by means of the deflection distance of the disc into the cavity. A helical coil spring assembly is employed to secure the indicator in fixed position within the installation bore.

Abstract: A miniaturized check valve comprises a generally tubular body including a cylindrical base and a guide sleeve of reduced diameter which axially extends from the base. The body forms a an interior valve seat which surrounds an axially extending fluid passageway. The guide sleeve has a plurality of angularly spaced discharge openings and a pair of pilot orifices which are axially spaced from the valve seat. A valve ball is displaced from the valve seat to form a fluid flow path which extends generally axially through the valve seat and into the guide sleeve and thereafter generally radially through the orifices and openings for flow exteriorly of the guide sleeve. The ball is biased by a spring assembly which comprises a pair of axially aligned springs having a relatively low pre-load force and low spring rate.

Abstract: A filter screen for filtering contaminant particles from the fluid system of a hydraulic system comprises a screen which forms an axially extended convoluted nipple-like enclosure which opens through a passage formed in a base and terminates at a nose portion opposite the base. The screen has folded sides which comprise a plurality of angularly spaced alternating generally convex surface sections and generally concave surface sections generally symmetrical to the central screen axis. The screen is folded to form a continuous serpentine rim configuration at the base. The serpentine rim comprises an inner plurality of angularly spaced fold segments which engage the exterior surface of the base and an outer plurality of angularly spaced fold segments which overlap the inner fold segments in an alternating fashion. The screen is shaped and dimensioned so that the surface area of the screen generally increases from the nose to the base of the screen.

Abstract: A piezoelectric valve with a cantilevered control arm assembly, comprising a piezoelectric valve operating arm and a contiguous limit arm for limiting the opening deflection of the valve operating arm.

Abstract: A miniature electromagnetic valve having a valve mechanism with three spaced parallel rods, a pair of generally semi-circular, resilient conductor tubes extending between the rods and a linear solenoid for selectively shifting the intermediate rod for selectively and individually pinching the tubes closed.

Abstract: A connector for Teflon tubing having a male connector with a tapered end providing a male conical sealing surface engageable with a conforming internal conical sealing surface machined in the end of the Teflon tubing. A collet having an annular collar conforming to and surrounding the interfitting male connector and end of tubing provides with the male conical sealing surface an axially extending wedge-shaped annulus for receiving and gripping the internally tapered end of the Teflon tubing.

Abstract: A valve system with an electromagnetically operated pilot valve for pneumatically actuating an operating piston of a primary valve for accurately metering, controlling and/or dispensing fluid with the primary valve. The piston is connected for pivoting a valve member actuating rod enclosed within a flexible tubular projection of a Teflon valve body via a rocker arm engageable with a free end of the tubular projection. Connectors for inlet and outlet Teflon conduits to the Teflon valve body have hard plastic inserts mounted within inlet and outlet passageways of the valve body between conforming sealing surfaces of the valve body and conduits.