Abstract: A well pump includes a piston and an inlet and/or outlet valve assembly of special structure. Each is formed of a body of organic polymer, preferably PTFE. Each includes a cavity in its upper portion and at least one passage leading from the cavity to the bottom of the block. A screen covers each cavity and a valve disk covers each screen. Flexible sealing flanges extend upwardly and downwardly from the periphery of the piston block. The outlet valve block has a sliding block and sealing fit with the piston rod.

Abstract: A groundwater monitoring system includes a bore, a well casing within and spaced from the bore, and a pump within the casing. A water impermeable seal between the bore and the well casing prevents surface contamination from entering the pump. Above the ground surface is a removable operating means which is connected to the pump piston by a flexible cord. A protective casing extends above ground and has a removable cover. After a groundwater sample has been taken, the cord is disconnected from the operating means. The operating means is removed for taking away, the cord is placed within the protective casing, and the cover closed and locked. The system is thus protected from contamination, as well as from damage by accident or vandalism.

Abstract: A tower drive mechanism is described for a self-propelled sprinkler system having a water conduit elevationally supported by spaced towers. Each tower has a frame with leg members extending downward and outward interconnecting with a cross axle tube. Tandem wheel assemblies are mounted on the frame adjacent respective ends of the axle tube. A single electric motor is connected to one of the wheel assemblies. An interconnecting drive shaft extends through the axle tube interconnecting the wheel assemblies so that the drive shaft does not become entangled with field debris or vegetation. The wheel assemblies and the motor have their individual worm gear reduction boxes.

Abstract: An articulating pipe coupling and alignment control assembly is described for center pivot sprinkler irrigation systems. The assembly interconnects adjacent pipe sections to enable the section to pivot both vertically and horizontally with respect to each other. The assembly includes two spaced pipe section flanges that are affixed to the ends of the pipe sections. Pipe segments are welded to the flanges with a coupling member fitting over ends of the pipe segments to enable water to flow therebetween. The assembly as an external ball and socket interconnection affixed to the pipe segments to enable the pipe sections to pivot about axes of the ball and socket interconnection. An articulating arm assembly is mounted above the ball and socket interconnection for operating a switch activating shaft to maintain the adjacent pipe section in general longitudinal alignment.