Patent GB-934993-A (GB)
Title: Pumping device for oil wells and the like
Inventor: BYRD JOSEPH PITTS
IPC: F04B47/02
Filed: 1959-11-16
Abstract: 934,993. Reciprocating pumps. OILFIELD EQUIPMENT CORPORATION OF COLORADO. Nov. 16, 1959, No. 38842/59. Class 102(1). In a pumping apparatus for oil wells and the like comprising a post 16, a beam 8 pivoted thereto at 9 and a horsehead 11 for attachment of the wire lines 12 for reciprocating the pump rod string, the rod, or rods, 10, connecting the beam and the crank or cranks 5, is pivoted to the beam adjacent to the horsehead. The crank circle is displaced towards the post 16 from vertical alignment with the path of the pivot 30 on the beam 8; and an arm 36, associated with each crank 5, carrying counterweight means 104 is out of alignment with the crank arm, these two features producing advantageous linear speed variations in the pump rods, and more effective balancing. The crank shaft 7 is driven by a prime mover 3 through a belt 14 and reduction gearing 2; and the throw of the, or each, crank is adjustable by screw means 96. The balance means comprises a main weight 104 which is fixed on the arm 36 and a smaller weight which is adjustable along the arm, as the arm rotates, either outwardly or inwardly according to the setting of a lever 156. The beam 8 is adjustable laterally by screwed tie rods 22 to align the horsehead with the well bore, and the beam may be torsionally deflected by screw jacks 29 to bring the horsehead 11 into true verticality to ensure that the wires 12 track correctly on the bearing surfaces in the horsehead. The reduction gearing 2 comprises a shaft 39 carrying a small sprocket driving a large chain wheel integral with a small sprocket which drives a large chain wheel on the crank shaft 7, the integral wheels being journalled on a non-rotatable shaft 38 supported in blocks 184 which are adjustable in directions at right angles by screw means 191, 197, the chain tensions being thus adjusted. The crank pin 32 of the crank 5 projects from a generally cylindrical member 33 having internal keyways which slide on keys 86, 87 on a generally tubular crank arm 34. The member 33 is adjusted along the arm 34 by the screw means 96 and is jammed thereon by wedges thrust into the bottom keyway by screws 95, the screws 94 abutting on the bottom key. A scale 88 denotes the position of adjustment. The arm 36 is box-like, is secured to the main lead weight 104 and backing weights 108, and slidably houses a smaller weight 122 which is moved axially of the arm 36 by a screw 111 and is pressed by a spring 126 to prevent laterally movement during rotation of the crank. A lay shaft 132 carries two star wheels 133, one of which is connected to the screw 111 by toothed wheels and the other by a chain drive 139 as shown in Fig. 22, so that the screw is rotated in one direction or the other according to which of the star wheels is actuated by a kicker 152 placed by the lever 156 in its path. One kicker is provided for each star wheel, each kicker being spring mounted so that it yields when the weight 122 reaches either end of its movement. When balance has been achieved, the lever 156 is set at neutral to remove both kickers from the paths of the star wheels. The horsehead is detached from the beam 8 by lifting a cross bar 67 and a distance piece 65, both secured between side plates 66 of the horsehead, out of notches 63, 64 respectively, a hanger bar 73 being provided for this purpose. The lines 12 run on tracks 71 and are attached at 72.