PUMPING UNIT Russian patent published in 1998 - IPC

FIELD: drives of sucker-rod well pumps in oil recovery. SUBSTANCE: pumping unit includes walking beam with head and crank mechanism mounted on frame of electric motor and reduction gear. Crank mechanism includes crank made in form of eccentric mounted on shaft of reduction gear, connecting rod, single-arm lever articulated with frame and double-arm lever provided with seat for eccentric. One arm of double-arm lever is articulated with single-arm lever and other arm carrying the balancing weight is articulated with connecting rod. Geometric axis of seat is shifted relative to geometric axis of double-arm lever passing through above-mentioned articulations. EFFECT: reduced torque on low-speed shaft of reduction gear, reduction of effect of length of connecting rod on change in load on shaft; slow upward motion and fast downward motion at reduced acceleration when load is maximum. 3 dwg