Abstract: A modular rotary metering unit comprising: a housing having at least one liquid inlet and liquid outlet; a rotatable member arranged to rotate about a longitudinal axis thereof with respect to the housing; and at least one bore passing through the rotatable member, the or each bore having two opposing ends and a shuttle element received therein, the shuttle element being movable between two terminal positions, each towards a respective end of the bore, wherein, when the rotatable member rotates, each bore moves in communication with a liquid inlet of the housing and a liquid outlet of the housing such that liquid can be received from the liquid inlet by the bore at the one end of the bore and the shuttle element can eject liquid from the other end of the bore to the liquid outlet, wherein respective first and second engagement elements are provided at first and second ends of the unit, each of the engagement elements being rotationally linked to the rotatable member.

Abstract: A metering device of the type in which a shuttle moves axially within a chamber between two terminal positions, with the chamber having fluid inlet and outlet at each end so that fluid may enter through one end to move the shuttle to cause fluid to be ejected through the other end, and vice versa. A control valve is provided to control the fluid flow, the control valve being a spool valve having a spool sealingly slidable within a bore, the spool valve being associated with a device to drive the spool between two alternate positions in response to the shuttle reaching each end of the chamber.

Abstract: A metering device that includes a housing defining a cylindrical chamber containing a reciprocating shuttle. The two opposed end parts of the chamber are interconnected by fluid flow ducts to a cylindrical valve bore. Contained with the valve is a rotary valve rod driven rotationally by a stepping motor. The valve rod has part cut away to form channels or recesses. In one rotational position of the valve rod a flow path is established from an inlet to one end of the chamber and a separate flow path is established from the other end of the chamber to an outlet. In an alternate orientation of the valve rod a flow path is formed from the inlet to the other end of the chamber and the first end of the chamber is connected to an outlet.

Abstract: A metering device that includes a housing defining a cylindrical chamber containing a reciprocating shuttle. The two opposed end parts of the chamber are interconnected by fluid flow ducts to a cylindrical valve bore. Contained with the valve is a rotary valve rod driven rotationally by a stepping motor. The valve rod has part cut away to form channels or recesses. In one rotational position of the valve rod a flow path is established from an inlet to one end of the chamber and a separate flow path is established from the other end of the chamber to an outlet. In an alternate orientation of the valve rod a flow path is formed from the inlet to the other end of the chamber and the first end of the chamber is connected to an outlet.

Abstract: A metering device contains a rotor which defines elongate chamber, there being a shuttle contained within the chamber movable between two terminal end positions. Frusto-conical surfaces defined on the rotor cooperate with annular members defining corresponding seats. One passage extends from one end of the chamber to one frusto-conical surface, and another passage extends from the other end of the chamber to the other frusto-conical surface. Each annual element defines a respective inlet and outlet for fluid and a shuttle is present within the chamber. As the rotor rotates, the shuttle effects a shuttling movement thus measuring dispensed volumes of fluid. A sensor is provided to detect physical contact of the shuttle with the end of the chamber to cause the rotor to advance.

Abstract: A metering device includes an inlet and outlet for a material (liquids, gases or solid particles) to be metered, a rotatable ball driven by a shaft and interposed between the inlet and outlet seats. The rotatable ball has a transverse bore containing a sealess shuttling member which can reciprocate back and forth along the bore between two sealing seats so as to seal against one or the other. The sealess shuttling member is propelled by pressurized material which flows into the bore without surface-to-surface contact of the shuttling member with the bore wall until is engages one of the two sealing seats. Each time the rotatable ball rotates 180.degree., a metered shot is ejected resulting in a quasi continuous flow depending upon a rotatable ball revolution rate.

Abstract: A metering device includes an inlet and outlet for a material (liquids, gases or solid particles) to be metered, a rotatable ball driven by a shaft and interposed between the inlet and outlet seats. The rotatable ball has a transverse bore containing a sealess shuttling member which can reciprocate back and forth along the bore between two sealing seats so as to seal against one or the other. The sealess shuttling member is propelled by pressurized material which flows into the bore without surface-to-surface contact of the shuttling member with the bore wall until is engages one of the two sealing seats. Each time the rotatable ball rotates 180.degree., a metered shot is ejected resulting in a quasi continuous flow depending upon a rotatable ball revolution rate.

Abstract: A material dispensing and metering piston pump comprising, in combination, a piston cylinder, an inlet defined in said cylinder for material to be dispensed, and an outlet defined in said cylinder for the said material, the inlet and the outlet being axially spaced from one another, and a piston comprising a piston rod and a piston head, the piston head comprising a member having a peripheral skirt outwardly and forwardly projecting therefrom, said member having one or more apertures extending there-through, there being a sealing member mounted on said piston rod, said member and said sealing member being movable relative to one another, said sealing member acting to seal said apertures when said member with said peripheral skirt and said sealing member are in one relative terminal position, the arrangement being such that the member and sealing member co-operate to seal said apertures when the piston head assembly moves material towards said outlet and to open said apertures when the piston head is withdrawn