WO2022214155A2 - Reciprocating-shaft piston pump - Google Patents

Abstract

Disclosed is a reciprocating-shaft piston pump, the aim of which is to reduce torque by 58% in comparison to axial piston pumps, at the same volume per single revolution (v/rev). This is achieved by means of a new piston drive design, wherein four pistons (19, 20, 21, 22) are connected to four reciprocating shafts (1, 2, 3, 4) having a diameter of 6.7 cm. The four reciprocating shafts have toothed lower parts (5, 6, 7, 8) in the form of a gear that rests on a toothed journal, having the same module (figure 2) with a surface angled at 5° to the horizontal axis (figure 1), and are attached inside a cylinder block (27) using assembling screws. When the cylinder block (27) is driven upwards by means of an eccentric drive shaft (30) having stroke length S₁ = 2.3 cm, the four reciprocating shafts are pulled upwards by two arms (13, 14) that rest on two pins (40, 41) attached to the cylinder block (27). As a result of this, the four reciprocating shafts slide on the surface of fixed cams (9, 10, 11, 12), such that they rotate horizontally about their axes in a linear manner, with stroke length S₂ = 1.78 cm, on the toothed journal (figure 1), the main shaft thereof being inclined at an angle of 31°, such that the two pistons (19, 20) are pushed inwards against the oil pressure (figure 2) with stroke length S₄ = 2.88 (figure 1), using the two reciprocating shafts (1, 2), and the two pistons (20, 21) are pushed outwards during the suction stroke with stroke length S₄ = 2.88, using the two reciprocating shafts (3, 4). Torque is reduced by 58% when v/rev = 0.25(A₁ + A₂ + A₄ + A₅) X S₄; v/rev = (A₁ + A₂ + A₄ + A₅) X S₄ – (A₃ + A₆) X S₁ Torque = [(pX(A1+A2+A4+A5)/0.93 - pX(A3+A6)X S1]/62.8.