A reciprocating-piston machine includes at least one first cylinder and at least one first piston assigned to the first cylinder as well as at least one second cylinder and at least one second piston assigned to the second cylinder. During operation, the first piston and the second piston are deflected in a respective cylinder displacement chamber of the respective first cylinder and the second cylinder. The reciprocating-piston machine further includes a crankshaft which, during operation, can be driven and which has an eccentric crankshaft journal and a drive shaft coupling designed for the coupling of a drive shaft of a drive motor for driving the crankshaft. Additionally, the reciprocating-piston machine includes a first connecting rod configured to deflect the first piston, a second connecting rod configured to deflect the second piston, and a bearing pin about which the first and second connecting rod are rotationally movable.

A pump system may include a plurality of motors coupled to a shaft and configured to cause the shaft to rotate, and a power end coupled to the shaft. The power end may include a plurality of yoke frames, each of which may include one or more push rods. The pump system may further include multiple fluid ends coupled to the power end. Each fluid end may include a cylinder chamber including a piston-plunger assembly configured to couple to one of the one or more push rods of the power end. The pump system may also include a device to disconnect or isolate one or more of individual piston assemblies, or one or more of the multiple fluid ends. The pump system may also include a multiplicity of controllers which may enhance performance, reliability, and operating life in a number of modes and conditions in a health management method.

A reciprocating piston machine includes a first cylinder and a first piston assigned to the first cylinder and a second piston assigned to the first cylinder or a second cylinder. The reciprocating piston machine further includes a crankshaft having an eccentric crankshaft journal and a drive shaft coupling configured for coupling a drive shaft of a drive motor for driving the crankshaft, a first connecting rod configured to deflect the first piston and configured to be moved by the eccentric crankshaft journal, and a second connecting rod configured to deflect the second piston and configured to be moved by a bearing pin. The reciprocating piston machine additionally includes at least one of a first elastomer element arranged between the bearing pin and the first connecting rod and a second elastomer element arranged between the bearing pin and the second connecting rod.

Apparatus for compressing cryogenic fluid in at least one compression stage comprising at least one piston and at least one sleeve delimiting at least one compression chamber, a shaft that is able to move in translation along a longitudinal axis (A), the shaft being connected to the piston(s) or sleeve(s) and being able to move with an alternating movement in two opposite directions to ensure phases of compression and intake of fluid into the at least one compression chamber by moving the at least one piston and the at least one sleeve in a relative manner, characterized in that the shaft comprises a portion of reduced cross section in the longitudinal direction (A), said portion of reduced cross section separating two adjacent parts of the shaft, the shaft also comprising at least one linking element made of material that is less thermally conductive than the constituent material of the shaft, in particular a composite material, said at least one linking element having two ends connected respectively to the two adjacent parts of the shaft.

A reciprocating piston machine includes a first cylinder and a first piston assigned to the first cylinder and a second piston assigned to the first cylinder or a second cylinder. The reciprocating piston machine further includes a crankshaft having an eccentric crankshaft journal and a drive shaft coupling configured for coupling a drive shaft of a drive motor for driving the crankshaft, a first connecting rod configured to deflect the first piston and configured to be moved by the eccentric crankshaft journal, and a second connecting rod configured to deflect the second piston and configured to be moved by a bearing pin. The reciprocating piston machine additionally includes at least one of a first elastomer element arranged between the bearing pin and the first connecting rod and a second elastomer element arranged between the bearing pin and the second connecting rod.

A reciprocating-piston machine includes at least one first cylinder and at least one first piston assigned to the first cylinder as well as at least one second cylinder and at least one second piston assigned to the second cylinder. During operation, the first piston and the second piston are deflected in a respective cylinder displacement chamber of the respective first cylinder and the second cylinder. The reciprocating-piston machine further includes a crankshaft which, during operation, can be driven and which has an eccentric crankshaft journal and a drive shaft coupling designed for the coupling of a drive shaft of a drive motor for driving the crankshaft. Additionally, the reciprocating-piston machine includes a first connecting rod configured to deflect the first piston, a second connecting rod configured to deflect the second piston, and a bearing pin about which the first and second connecting rod are rotationally movable.

A reciprocating-piston machine, in particular a two-stage or multi-stage piston compressor, includes: a first connecting rod for deflecting a first piston and which has a connecting-rod eye, the first connecting rod being a drive connecting rod; a second connecting rod for deflecting a second piston and which has at least one further connecting-rod eye, the second connecting rod being a follower connecting rod; a coupling element which extends through the connecting-rod eye and the at least one further connecting-rod eye and about which the first connecting rod and the second connecting rod are rotationally movable relative to one another; a coupling bearing element arranged between the coupling element and a connecting-rod eye inner surface of the connecting-rod eye; and a damping element with elastic damping action arranged in a damping annular chamber between the coupling bearing element and the connecting-rod eye inner surface of the connecting-rod eye.

A borehole pump assembly operable in association with for a borehole with a well casing therein, the borehole pump assembly including an elongate pump rod operably connected to a reciprocating drive and mounting a reciprocating pump at the lower end within the well casing and an air chamber provided immediately above the reciprocating pump and concentrically about the pump rod to provide hydraulic shock absorption between the reciprocating pump and a delivery pipeline.

A borehole pump assembly operable in association with for a borehole with a well casing therein, the borehole pump assembly including an elongate pump rod operably connected to a reciprocating drive and mounting a reciprocating pump at the lower end within the well casing and an air chamber provided immediately above the reciprocating pump and concentrically about the pump rod to provide hydraulic shock absorption between the reciprocating pump and a delivery pipeline.

A piston pump for a brake including: a piston housing; an outer piston which rectilinearly reciprocates in the piston housing; an inner piston which is coupled to an inner portion of the outer piston, and rectilinearly reciprocates together with the outer piston in a state in which the inner piston is coupled to the inner portion of the outer piston, or rectilinearly reciprocates alone in a state in which the outer piston is stopped; an outer return spring which supports a tip portion of the outer piston; an inner return spring which supports a tip portion of the inner piston; and a piston rod spring which supports rear end portions of the outer piston and the inner piston.