Abstract: A downhole pump includes a pump barrel defining a pumping chamber having a first end and a second end, a first one-way valve positioned at the first end of the pumping chamber, a second one-way valve positioned at the second end of the pumping chamber and a plunger movable disposed in the pumping chamber. The first one-way valve is operable to permit a flow of fluid out of the first end of the pumping chamber, while the second one-way valve is operable to permit a flow of fluid out of the second end of the pumping chamber. The plunger has first and second ends facing the first and second ends of said pumping chamber respectively. The pumping chamber has an inlet adapted to be in flow communication with a production zone. The plunger is movable in the pumping chamber between at least a first position and a second position.

Abstract: A downhole pump includes a pump barrel defining a pumping chamber having a first end and a second end, a first one-way valve positioned at the first end of the pumping chamber, a second one-way valve positioned at the second end of the pumping chamber and a plunger movable disposed in the pumping chamber. The first one-way valve is operable to permit a flow of fluid out of the first end of the pumping chamber, while the second one-way valve is operable to permit a flow of fluid out of the second end of the pumping chamber. The plunger has first and second ends facing the first and second ends of said pumping chamber respectively. The pumping chamber has an inlet adapted to be in flow communication with a production zone. The plunger is movable in the pumping chamber between at least a first position and a second position.

Abstract: A crude oil recovery system includes a downhole pump and an extension that extends below the downhole pump. The extension has an extension inlet positioned below the lowest drawdown level achievable by the pump. All of the fluid pumped by the downhole pump enters the extension via the extension inlet, and by positioning the extension inlet sufficiently below the lowest drawdown level achievable by the pump, pressurized gas is prevented from entering the extension, the pump, or the pump column above the pump. In this way, gas is prevented from displacing oil in the pump column, thereby maintaining excellent cooling for the polish rod, and gas is confined to the borehole annulus, where it can readily be recovered or vented.

Abstract: A crude oil recovery system includes a downhole pump and an extension that extends below the downhole pump. The extension has an extension inlet positioned below the lowest drawdown level achievable by the pump. All of the fluid pumped by the downhole pump enters the extension via the extension inlet, and by positioning the extension inlet sufficiently below the lowest drawdown level achievable by the pump, pressurized gas is prevented from entering the extension, the pump, or the pump column above the pump. In this way, gas is prevented from displacing oil in the pump column, thereby maintaining excellent cooling for the polish rod, and gas is confined to the borehole annulus, where it can readily be recovered or vented.

Abstract: A hydraulic pump includes a pump mechanism having a driven shaft. The driven shaft is connected to an input shaft by a flexible coupling such as a splined connection. A housing extends completely around the driven shaft, and a high-pressure seal is disposed between the housing and the input shaft. A thrust bearing carries hydraulic axial forces on the input shaft to the housing. This arrangement provides balanced hydraulic forces on both ends of the driven shaft, thereby reducing friction and wear.

Abstract: A hydraulic system includes a hydraulic fluid pump, a hydraulic cylinder, and a pressure accumulator. A hydraulic fluid valve is movable between a first position and a second position. In the first position, the valve directs fluid from the pump outlet to the hydraulic cylinder and from the accumulator to the pump inlet. In the second position the valve directs fluid from the pump outlet to the accumulator and from the hydraulic cylinder to the pump inlet. In this way pressurized hydraulic fluid from the cylinder can be stored in the accumulator for reuse. The pump includes high pressure seals at both ends of the driven shaft in order to reduce or eliminate offset forces of the type that might increase friction and wear.

Abstract: An animal trap includes a housing that defines an entry port. A pair of animal-actuated, gravity-lowered doors are mounted adjacent to the entry port such that each opens inwardly only. The inner and outer doors are coupled together to substantially prevent the inner door from opening in the inward direction when the outer door is in a closed position.

Abstract: A drive system for a down hole oil well pump includes a cylinder assembly which defines first and second cylinders. A pump rod which includes first and second pistons, each disposed in a respective one of the cylinders, is coupled to the down hole pump. A hydraulic accumulator supplies a resilient biasing force to one of these pistons to counter the weight of the ram interconnecting the pump rod and the down hole pump. A hydraulic pump supplies pressurized hydraulic fluid which is alternately directed against upwardly facing and downwardly facing piston faces of the pump rod to cause the pump rod to oscillate, thereby driving the down hole pump. Fluid level sensors deactivate the hydraulic pump when the oil level in the oil well falls below a pre-set level.

Abstract: A seed cleaning device includes a frame and first and second screened grids, each of which is pivotably mounted to the frame. Two crankshafts are mounted to the frame and are coupled to one another to remain 180 degrees out of phase with respect to one another. Each of the crankshafts causes a respective one of the screened grids to oscillate, such that the oscillation of the first screened grid is out of phase with the oscillation of the second screened grid.

Abstract: A seed dispensing apparatus includes an upper grain flute housing which mounts a grain flute type seed dispensing system, as well as a lower seed plate housing which mounts a seed plate type dispensing system. Both the flute type dispensing system and the seed plate type dispensing system include respective drive shafts. By selecting and rotating the appropriate one of the drive shafts, the disclosed seed dispensing system can be used either to dispense relatively small seeds via the flute type dispensing system, or relatively large seeds via the seed plate type dispensing system.