Abstract: A pump having a hollow cylinder, and a piston slidably received in the cylinder, with the piston dividing the inside of the cylinder into two chambers. A hollow piston rod has one end connected to the piston and the other end extending out of the cylinder, and means is provided for attaching the other end of the piston rod to an inflatable member. The pump has one-way valve means adjacent each end of the cylinder to permit passage of air into each chamber, while preventing passage of air out of the chambers. Valve means is carried by the piston to establish communication between either of the chambers and the piston rod when the pressure in either chamber exceeds the pressure in the piston rod and inflatable member.

Abstract: The present invention comprises a small, precise measuring pump provided with a germ barrier that is specifically designed for intravenous feeding devices in which the fluid being pumped is positively displaced; in which there is no rubbing contact of one member with another which would be destructive of blood being pumped; the pumping chambers are small, so that they will hold as little fluid as possible; and in which the valves are actuated by gravity and which are tight-sealing when the pump is in a substantially vertical position, but which, when the pump is tipped on its side, are open to permit the preliminary filling of the pump with the fluid to be pumped.

Abstract: The invention provides an air compressor of low cost, high quality, long life and of simple and rugged construction and ready replaceability of the chief wear parts as a unit. The compressor employs a wobble piston with a Teflon or equivalent packing on the wobble piston, which packing bears against the surface of a working cylinder of aluminum with a hardened polished surface. The working cylinder in the form of a cylindrical sleeve is seated at its lower end on a circular shoulder in the main housing or frame. At its upper end it is seated and sealed in a groove in a head plate which provides a cylinder head for the cylinder and a closure for the top of the main frame. An inverted cup shaped delivery chamber rests upon and is secured to and sealed by an O-ring of heat resistant rubber to the head plate to receive the delivery of compressed gas and to provide anchorage for a delivery pipe or pipes.

Abstract: This invention provides the fluid-handling device which includes a curved base member of which the surface is closed upon its self, for example a truncated cone, and an elastomeric member adapted to receive and enclose the base member. The elastomeric member defines a number of chambers at its contact with the base member, these including an inlet chamber divided by a sloping partition integral with the elastomeric member, and a outlet chamber also divided by a sloping partition intergral with the elastomeric member. The elastomeric member also includes a dome adjacent the end or truncation of the base member, and this dome defines with the base member a chamber of variable volume, which is connected to the inlet and outlet chambers by suitable passageways which result in a pumping action when the dome is depressed and then released.

Abstract: A reciprocating type pump has a pair of body members with complementary concave and convex surfaces which clamp a flexible sheet means therebetween to hold the same in curved configuration. The member having the convex surface has a pump chamber opening toward the flexible sheet means and the concave member has inlet and outlet passages opening toward the flexible sheet. The flexible sheet has portions overlying such inlet and outlet passages and the overlying portions have free edge portions extending in the direction of curvature of the flexible sheet and adapted to be flexed toward said convex surface member by fluid pressure from said passages whereby the overlying portions of the flexible sheet are reversely curved under the force of said fluid pressure and return resiliently to original passage closing condition when such pressure is not acting thereagainst.

Abstract: A diaphragm compressor includes a cylindrical piston and an annular diaphragm member with a central hub secured by a grommet within an annular recess in the piston face. The outer peripheral edge of the diaphragm is affixed between a clamp ring and a valve plate which has a central recess to form a compression chamber. The diaphragm has a convolution which opens toward the compression chamber. The valve plate has a projection complementing and mating with the convolution. A plurality of circumferentially spaced and radial intake ports lead to an annular piston intake opening inwardly of the diaphragm. A flexible, tee-shaped valve member includes a stem locked within the piston with a planar sealing disc having an outer bead abutting the inner piston face and overlying the intake opening. The stem may pass through a central opening with an outer stem enlargement creating a resilient clamping of the valve member to a holding portion of the piston.