OIL-WELL SUCKER-ROD PUMP Russian patent published in 1995 - IPC

FIELD: oil industry. SUBSTANCE: bushing is mounted on the ring projection provided on the hollow housing of the pump for permitting rotation about the central axis. A sealing member is mounted at the level of the ring projection. A plunger is mounted inside the hollow housing for permitting axial movement. The sealing member is interposed between the housing and plunger. Semiaxles provided with rollers are arranged on the diametrically opposite sides of the plunger to be shifted over the height. Each semiaxle having the roller is additionally provided with a cam. Grooves are made in the hollow housing oppositely to each of the semiaxle. The axle provided with rollers at its ends is mounted on the plunger. The rollers are exerted by a spring through a bushing. As a result, the rollers are pressed to the cams. Grooves, which are similar to the grooves mentioned above, are made in the hollow housing for longitudinal movement of the axle. EFFECT: enhanced efficiency. 2 dwg