This is a method and apparatus for controlling an oil-well beam pumping unit in a manner which allows increased oil production. The AC electric motor of the beam pumping unit is supplied power through a variable frequency power supply, whose frequency (and voltage) is controlled by circuitry to automatically adjust to whatever flow enters the wellbore by varying the speed of the pumping unit to maintain the speed generally proportional to the real power consumed by the pump. As the level in the wellbore can be maintained at an essentially constant minimum level, despite the relatively large hour-to-hour variations in in-flow which normally occur, the total flow from the formation into the wellbore in a given period of time is increased.

An improved pulsation-free reciprocating volumetric pump is disclosed, which comprises two reciprocating plungers, a cam for driving said plungers, a driving motor connected to said cam, a circuit connected to said driving motor for controlling rotational rate, and another circuit for detecting a pressure of combined volume discharged by the two plungers and for correcting a control signal of said rotation controlling circuit through the detected signal.

A fluid pump mechanism for delivering a smooth output of fluids to a system utilizing at least one piston in a chamber reciprocative therewithin. The piston has strokes that fill and empty the chamber in conjunction with the action of valve means located at the inlet and outlet of the chamber. Motive means causes reciprocation of the piston within the chamber. Control means is also included for minimizing the time during the piston cycle in which the piston is not emptying the chamber. The invention's scope also encompasses a pressure metering device for a fluid forcing means motivated by an electrical motor.

A fluid pump mechanism for delivering a smooth output of fluids to a system utilizing at least one piston in a chamber reciprocative therewithin. The piston has strokes that fill and empty the chamber in conjunction with the action of valve means located at the inlet and outlet of the chamber. Motive means causes reciprocation of the piston within the chamber. Control means is also included for minimizing the time during the piston cycle in which the piston is not emptying the chamber. The invention's scope also encompasses a pressure metering device for a fluid forcing means motivated by an electrical motor.

A manually adjustable constriction or orifice to provide a means for optimizing the hydraulic power being converted to heat in a hydraulic windpower conversion system. The hydraulics and constriction are arranged to obtain the proper conditions necessary so that pressure head is converted to velocity head with the sum of the two remaining constant. Instrumentation to facilitate this optimizing adjustment process. A combination of a pump-speed transducer and a pressure-sensing transducer, along with appropriate electronic circuitry is described which provides an output display of the power being converted to heat. Instrumentation to accumulate and display the total energy converted to heat. Electronic devices and display equipment transform hydraulic power signals into energy signals, totalize the energy signals over time, and periodically display the accumulated energy count.