Abstract: A valveless, positive displacement pump including a living hinge for angularly adjusting a pumping head with respect to a rotatable drive member is provided. A method of manufacturing such a pump is also provided. The pump includes a block to which a pumping head and drive member are mounted. The block includes a first support pivotably connected to a second support by means of an integral, flexible hinge. The pumping head is mounted to the first support while the rotatable drive member is mounted to the second support. Movement of the first support about the flexible hinge allows the stroke of the piston, and therefore the flow rate of the pump, to be adjusted. Such a pump may be manufactured by extruding the block in elongate form and then cutting it into individual sections to which pumping heads may be mounted.

Abstract: A valveless, positive displacement metering pump is provided by the invention. Such a pump includes a housing, a working chamber within the housing, a piston within the working chamber, the piston including a duct defined by a portion of its outer surface, one or more inflow ports communicating with the working chamber, one or more outflow ports communicating with the working chamber, and a drive cylinder for simultaneously rotating the piston and causing it to move in back and forth strokes within the working chamber. The housing is rotatable with respect to the piston to adjust the timing of the fluid communication between the duct and the inflow and outflow ports, respectively. Such adjustments in timing allow the flow rate of the pump to be fine tuned, and allow each port to experience a partial suction as well as a partial discharge.

Abstract: A valveless, positive displacement pump including a living hinge for angularly adjusting a pumping head with respect to a rotatable drive member is provided. The pump includes a block to which a pumping head and drive member are mounted. The block includes a first support pivotably connected to a second support by means of an integral, flexible hinge. The pumping head is mounted to the first support while the rotatable drive member is mounted to the second support. Movement of the first support about the flexible hinge allows the stroke of the piston, and therefore the flow rate of the pump, to be adjusted. Such a pump may be manufactured by extruding the block in elongate form and then cutting it into individual sections to which pumping heads may be mounted.

Abstract: A valveless, positive displacement metering pump is provided which is capable of either mixing two or more fluids or dividing a fluid from an inflow line into two or more outflow lines. The pump includes a housing which contains a cylindrical working chamber at different radial positions. Three or more passages extend through the housing and communicate with the working chamber. A piston is positioned within the working chamber. The piston includes a duct defined by its outer surface which communicates with one of the passages, depending upon its rotational position. The piston is rotated as it is driven back and forth within the cylinder, thereby causing the duct to sequentially communicate with the passages and the piston to sequentially close the passages. Depending upon the axial direction of movement of the piston, fluid is either pumped into or out of the working chamber as the duct rotates into communication with one of the passages.