Abstract: A check valve for a compressed gas system. The valve has a body with an internal passage extending through the body and a valve seat positioned in the passage. A poppet is movable between a closed position in which the poppet engages the seat to block flow of gas through the passage and an open position in which the poppet is spaced from the seat to permit flow of gas. A retainer mounts the poppet in the passage and guides movement of the poppet. A spring urges the poppet to the closed position such that the poppet is responsive to pressure of the gas exceeding a predetermined value to move the poppet away from the seat against the urging of the biasing member and to the open position.

Abstract: A check valve for a compressed gas system. The valve has a body with an internal passage extending through the body and a valve seat positioned in the passage. A poppet is movable between a closed position in which the poppet engages the seat to block flow of gas through the passage and an open position in which the poppet is spaced from the seat to permit flow of gas. A retainer mounts the poppet in the passage and guides movement of the poppet. A spring urges the poppet to the closed position such that the poppet is responsive to pressure of the gas exceeding a predetermined value to move the poppet away from the seat against the urging of the biasing member and to the open position.

Abstract: A thermal relief valve to be mounted in a fluid flow line. The valve comprises a valve body and a valve actuator movable in a bore defined by a bore wall in the valve body from a sealing position in which the actuator sealingly engages a valve seat to block flow through the valve to a non-sealing position. The valve actuator is responsive to the temperature of the fluid exceeding a predetermined temperature to move to its non-sealing position. The relief valve has an actuator body configured to have first exterior surfaces sized for a close clearance fit with the bore wall at spaced locations around the actuator body to prevent substantial lateral shifting of the body relative to the bore wall, and second exterior surfaces which extend between the first exterior surfaces and which are spaced farther from the bore wall to define flow passages to permit the flow of fluid past the actuator when the valve actuator moves to its non-sealing position.

Abstract: A dielectric resonator device includes an enclosure having a bottom wall, a pedestal made of quartz seated inside the enclosure on the bottom wall, a dielectric resonator element seated on the pedestal, a bracket made of quartz for holding the dielectric resonator down on the pedestal and a clamping disc and screws for securing the bracket to the bottom wall.

Abstract: A method of making a positive temperature coefficient of resistance (PTCR) device, and the PTCR device itself, where there is provided a ferroelectric semiconductor having a Curie point and a bulk resistance. A layer of electrically conducting material is provided upon the ferroelectric semiconductor. The layer is heated at a process temperature greater than the Curie point of the ferroelectric semiconductor for a period of time, and cooled to ambient temperature. The process temperature and time period are selected to be sufficent to provide an ambient layer resistance greater than the bulk resistance of the ferroelectric semiconductor. The layer may be heated in an oxidizing atmosphere or in a reducing atmosphere, which also affects the layer resistance. The ferroelectric semiconductor may be in the form of an oxide ceramic or liquid crystals, and may include barium titanate. The layer may be selected from the group consisting of metal, metal alloys, metal oxides, polymers, and composites thereof.

Abstract: A system of dielectric ceramic compositions suitable for various microwave applications. The system comprises a plurality of stoichiometrically-related compositions, each composition having its own particular set of dielectric properties and consisting essentially of a sintered mixture represented by the general formula:BaTi.sub.4-w M.sub.w O.sub.9 --xZn.sub.2 TiO.sub.4 --yBaO--zTa.sub.2 O.sub.5wherein M is at least one type of metal and 0.0.ltoreq.w.ltoreq.about 0.05 and wherein x, y, and z are molar fractions of respective components with values within the following respective ranges: 0.0.ltoreq.x.ltoreq.about 0.45; about 0.01.ltoreq.y.ltoreq.about 0.20; and 0.0.ltoreq.z.ltoreq.about 0.10.

Abstract: A method of making a positive temperature coefficient of resistance (PTCR) device,and the PTCR device itself, where there is provided a ferroelectric semiconductor having a Curie point and a bulk resistance. A layer of electrically conducting material is provided upon the ferroelectric semiconductor. The layer is heated at a process temperature greater than the Curie point of the ferroelectric semiconductor for a period of time. End cooled to ambient temperature. The process temperature and time period are selected to be sufficient to provide an ambient layer resistance greater than the bulk resistance of the ferroelectric semiconductor. The layer may be heated in an oxidizing atmosphere or in a reducing atmosphere which also affects the layer resistance. The ferroelectric semiconductor may be in the form of an oxide ceramic or liquid crystals, and may include barium titanate. The layer may be selected from the group consisting of metal, metal alloys, metal oxides, polymers, and composites thereof.

Abstract: A telephone protector comprises an encapsulated bidirectional voltage sensitive switch having three terminals protruding therefrom, one of the terminals being a grounding terminal. There is an elongated shorting bar substantially orthogonal to the three terminals and a metal fusible pellet in direct physical contact with both the grounding terminal and the shorting bar. There is a spring which impels the shorting bar into contact with the other two terminals when the fusible pellet melts.

Abstract: A valve for controlling flow of air from a source of air under pressure such as a compressed air tank comprising an elongate body with first and second ends and first and second sides lying opposite one another. A transverse opening, extending between the first and second sides of the body adjacent its first end, has five coaxial sections of circular cross section having various diameters. The valve further includes a valve stem having a head with a pair of annular grooves in it, each holding an O-ring. The O-ring closest to the inner end of the head is engageable with a valve seat provided in of the transverse opening on inward movement of the stem to close the valve. A knob is attached to the valve stem to facilitate moving the stem. The valve stem with the O-rings in the grooves but without the knob is capable of assembly by inserting the stem into the opening from one side of the body.

Abstract: A manifold fitting for a compressed air tank having an elongate main body of hexagonal cross-section with first and second ends, the first end being of reduced circular cross-section, the body having an axial passage extending from the first end toward and terminating short of the second end. The first end is externally threaded for attachment of the fitting to a tank for communication with the tank via the passage. The body has a lateral opening extending inwardly from a one of its six faces to said passage and a pressure relief safety valve at the lateral opening in the body. A passage extends across the body and intersects the lateral opening.

Abstract: A manifold fitting for a compressed air tank comprising an elongate main body of hexagonal cross-section having an axial passage for communication with the tank, a first lateral opening extending from a first face of the body, an outlet member threaded in the first lateral opening having a valve seat at its inner end and a second lateral opening extending from a second face opposite the first. A valve member is threaded in the second lateral opening extending across the stem with an axial passage therein extending inwardly partway from its outer end to at least one port in the valve stem for communication with the axial passage. A filler check valve is located in the axial passage for filling the tank with compressed air via application of a coupling at the end of a compressed air supply to said stem. A third lateral opening extends inwardly from a third face to said passage and has a pressure relief safety valve therein.

Abstract: A manifold fitting for a compressed air tank having an elongate main body with a passage therethrough from one end to the other. The main body has an end portion at one end of the passage adapted for attachment of the fitting to a tank and a second end portion at the other end of the passage. The main body further has an outlet member, a valve member, and a pressure relief safety valve, each of which are threaded into lateral openings in the main body. A fourth threaded lateral opening is provided for a pressure gauge.

Abstract: In a spring-loaded valve, a coil spring functions not only to bias a valve member toward its seat but also to retain the valve member in assembly with the valve.

Abstract: An unloader/check valve for use with an air compressor comprising a one-piece valve body, a valve member slidable in the body between open and closed positions, biased toward its closed position, the valve having a bleed for unloading the compressor when the valve member is in its closed position, and a dashpot arrangement for damping pulsations of the valve member.

Abstract: A manifold assembly for a compressed air storage tank or the like having a main flow passage therethrough, ball valve means and pressure relief means. The ball valve means comprises a ball valve member received in a lateral bore extending generally perpendicularly through the passage. The ball valve member has a spherical ball portion with an aperture therethrough and a pair of circular sealing heads, one on each side of the ball portion. Each of the sealing heads carries a seal which is slidably and sealingly engageable with the walls of the lateral bore. The sealing heads are of substantially equal diameter so that pressure forces acting on the ball valve member which tend to move the latter axially within the bore are balanced. A seal body is insertable into a main flow passage of the valve body from one end thereof for sealingly engaging the ball portion after the ball valve member has been installed in the lateral bore.

Abstract: A ball valve having a valve body, a main flow passage therethrough, a lateral bore extending generally perpendicularly through the passage, and a unitary ball valve member received in the lateral bore. The ball valve member has a spherical ball portion with an aperture therethrough and a pair of circular sealing heads, one on each side of the ball portion. Each of the sealing heads carries a seal which is slidably and sealingly engageable with the walls of the lateral bore. The sealing heads are of substantially equal diameter so that pressure forces acting on the ball valve member which tend to move the latter axially within the bore are balanced. A seal body is insertable into a main flow passage of the valve body from one end thereof for sealingly engaging the ball portion after the ball valve member has been installed in the lateral bore.