| 20090000790 | Short stroke piston pump - A short stroke piston pump for recovering oil and/or water from marginal stripper wells, tar sands and coal beds includes a motor connected to one end of a drive rod, the motor capable of moving the drive rod in a generally up and down direction. A piston is connected to another end of the drive rod, the piston and drive rod are disposed in a riser pipe, the piston is adapted to transport fluid up the riser pipe as the piston moves up and down in the riser pipe. Additionally, a controller is communicatively connected to the motor, the controller changing speed and direction of the motor in response to a location or status of the drive rod within the riser pipe | 01-01-2009 |
