US 4,374,486 AGranted

Radial piston motor or pump

OwnerKarl Eickmanninventor

Life of this patent

Estimating the term…

Loading patent…

Abstract

In a radial piston pump, motor, transmission the deep diving or entering piston shoe is utilized and swingably borne in the pivot-bed of the radially reciprocating piston. Since deep diving piston shoes have large piston strokes, the shoes pivot in the pistons in large angles. Thereby a considerable force-portion of the load on the piston is transfered to the wall between the piston and the cylinder, whereby heretofore short pistons produced occasionally welding and sticking between the cylinder wall and the piston wall. The piston therefore receives radially extending portions, which may extend beyond the medial portions of the piston show and may even enter into the ring groove of the piston stroke actuator ring. Thereby a very long guidance of the piston on cylinder wall portions is obtained, which makes the application of effective pressure balancing pockets at correct location between piston wall and cylinder wall possible. An extended piston guide and friction--less travel of the piston in the cylinder without wearing or sticking is assured.

Claims27

Dependent claims

In a radial piston device, wherein fluid flows from inlet means through passages into and through substantially radially arranged cylinders of a rotor revolvably mounted in a housing of said device and discharges out from said cylinders through passages and outlet means,

the combination of pistons reciprocating in said cylinders, slippers interposed between a piston stroke actuator means and the pistons, a slipper-piston bearing for each individual piston and slipper located parallel to the axis of rotation of said rotor which makes said slipper tiltable and pivotable on the respective bearing bed in the respective piston;
an "H-form" of each individual slipper when seen from top, having slots between the guide portions of said slipper laterally of said slots;
each individual cylinder of said cylinders provided with wall-portions which extend from portions of the wall of said cylinder in the directions of said respective portions of the wall of said cylinder along respective radial extension segments of said rotor;
and an improvement;
wherein said improvement consists in the provision of radial extensions of portions of said pistons in radially outward direction relative to said rotor,
wherein said extensions are located perpendicular to the axis of said slipper-piston bearing and at least partially outwardly of said rotor,
wherein retaining means are provided between said extensions and radially outwardly of a portion of said slipper for holding said piston and slipper in a joint and tiltable disposition, and;
wherein said extensions form face portions extending from the outer face of said piston in the direction of the respective portion of said outer face of said piston to be guided at least partially on said wall portions of said cylinder and to radially slide therealong.

5 more elements

the combination of pistons reciprocating in said cylinders with piston-shoes interposed between a piston stroke guide and actuator means and the pistons, a piston shoe-piston bearing for each individual piston and shoe located parallel to the axis of rotation of said rotor which makes said piston-shoe pivotable on the respective bearing bed in the respective piston;
an "H-form" of each individual shoe when seen from top, having slots between the guide portions which are located laterally of said slots on said shoes;
each individual cylinder of said cylinders provided with wall-portions which extend from portions of the wall of said cylinder in the directions of said respective portions of the wall of said cylinder along respective radial extension segments of said rotor;
and an improvement;
wherein said improvement consists in the provision of radial extensions of portions of said pistons in radially outward direction relative to said rotor,
wherein said extensions are located perpendicular to the axis of said piston shoe-piston bearing and at least partially outwardly of said rotor,
wherein retaining means are provided between said extensions and radially outwardly of a portion of said piston-shoe for holding said piston and shoe in a joint and pivotable arrangement of said shoe on said piston, and,
wherein said extensions form face portions extending from the outer face of said piston in the direction of the respective portion of said outer face of said piston to be guided on said wall portions of said cylinder and to radially slide therealong.

5 more elements

Dependencies are inferred from the claim text.