The device comprises an internal distributor to be disposed in a casing portion (10A), and comprising a body (15) that has an outside axial face (15B) provided with two grooves (17, 19) respectively for feed and for discharge. The distributor has distribution ducts (23A, 23B, 23C) that open out in a distribution radial face and a cylinder capacity selector that comprises a slide (50) suitable for being moved in an axial bore (53) for connecting the distribution ducts to one or the other of the grooves. The device further comprises a control chamber (52) provided between a first end wall (15′) of the bore and the first end (50A) of the slide, and an opposing spring (55) disposed in a return chamber (52′) situated at the second end (53″) of the bore and closed, at the end closer to the distribution face (15A), by a second end wall (55′) of the distributor.

A low-force, non-displacement, micro/miniature valve and/or pump assembly is provided. A tube component having a first side port coupled to an inlet portion and a second side port coupled to an outlet portion can be selectively moved to alternatively couple the side ports to a first or second piston pump chamber. First and second pistons can be actuated after positioning the tube component to either draw in fluid or push out fluid from either the first or second piston pump chambers during each actuation of the pistons. The fluid can be drawn in from a reservoir and can be expelled to a patient for providing a dose of the fluid to the patient.

A low-force, non-displacement, micro/miniature valve and/or pump assembly is provided. A tube component having a first side port coupled to an inlet portion and a second side port coupled to an outlet portion can be selectively moved to alternatively couple the side ports to a first or second piston pump chamber. First and second pistons can be actuated after positioning the tube component to either draw in fluid or push out fluid from either the first or second piston pump chambers during each actuation of the pistons. The fluid can be drawn in from a reservoir and can be expelled to a patient for providing a dose of the fluid to the patient.

A hydraulic piston machine including a housing, a shaft that is able to rotate relative to the housing, and a cam secured to one of the housing or the shaft. A cylinder block includes pistons that are able to move in the cylinder block opposite the cam in order to generate relative rotation between the cylinder block and the cam. The cylinder block is linked in rotation to the other of the shaft or the housing. A mechanism forms rotation guide bearings for guiding the rotation of the shaft relative to the housing, which mechanism includes a tapered plain bushing interposed between a housing element and an element linked in rotation with the shaft and in which the tapered plain bushing includes a radial through-slit extending through the entire radial dimension of the bushing.

A hydraulic piston machine including a housing, a shaft that is able to rotate relative to the housing, and a cam secured to one of the housing or the shaft. A cylinder block includes pistons that are able to move in the cylinder block opposite the cam in order to generate relative rotation between the cylinder block and the cam. The cylinder block is linked in rotation to the other of the shaft or the housing. A mechanism forms rotation guide bearings for guiding the rotation of the shaft relative to the housing, which mechanism includes a tapered plain bushing interposed between a housing element and an element linked in rotation with the shaft and in which the tapered plain bushing includes a radial through-slit extending through the entire radial dimension of the bushing.

A hydraulic system has two hydraulic circuits, each with a pressure generating unit acting on an actuator unit. The generating units are slot-controlled radial piston pumps and form a pump assembly with a single common pump support and single common rotor. The rotor is rotatable on a free protruding section of a common support hub and has piston-receiving bores on axially offset planes. The hub has two first and two second fluid bores. The first bores communicate with first pump connections and first control openings on the hub on a first plane, and the second fluid bores communicate with second pump connections and second control openings on the hub on a second plane. A first and a second adjustment frame, each having an eccentric ring and acting on the pump pistons, are disposed on respective planes perpendicular to the main axis and independently guided in a linearly movable manner.

A hydraulic system has two hydraulic circuits, each with a pressure generating unit acting on an actuator unit. The generating units are slot-controlled radial piston pumps and form a pump assembly with a single common pump support and single common rotor. The rotor is rotatable on a free protruding section of a common support hub and has piston-receiving bores on axially offset planes. The hub has two first and two second fluid bores. The first bores communicate with first pump connections and first control openings on the hub on a first plane, and the second fluid bores communicate with second pump connections and second control openings on the hub on a second plane. A first and a second adjustment frame, each having an eccentric ring and acting on the pump pistons, are disposed on respective planes perpendicular to the main axis and independently guided in a linearly movable manner.

A low-force, non-displacement, micro/miniature valve and/or pump assembly is provided. A tube component having a first side port coupled to an inlet portion and a second side port coupled to an outlet portion can be selectively moved to alternatively couple the side ports to a first or second piston pump chamber. First and second pistons can be actuated after positioning the tube component to either draw in fluid or push out fluid from either the first or second piston pump chambers during each actuation of the pistons. The fluid can be drawn in from a reservoir and can be expelled to a patient for providing a dose of the fluid to the patient.

A low-force, non-displacement, micro/miniature valve and/or pump assembly is provided. A tube component having a first side port coupled to an inlet portion and a second side port coupled to an outlet portion can be selectively moved to alternatively couple the side ports to a first or second piston pump chamber. First and second pistons can be actuated after positioning the tube component to either draw in fluid or push out fluid from either the first or second piston pump chambers during each actuation of the pistons. The fluid can be drawn in from a reservoir and can be expelled to a patient for providing a dose of the fluid to the patient.

A low-force, non-displacement, micro/miniature valve and/or pump assembly is provided. A tube component having a first side port coupled to an inlet portion and a second side port coupled to an outlet portion can be selectively moved to alternatively couple the side ports to a first or second piston pump chamber. First and second pistons can be actuated after positioning the tube component to either draw in fluid or push out fluid from either the first or second piston pump chambers during each actuation of the pistons. The fluid can be drawn in from a reservoir and can be expelled to a patient for providing a dose of the fluid to the patient.