Abstract: A hydraulic device (1) comprises a housing (2) and a shaft (3) which is rotatable about a first axis of rotation (4). The shaft (3) has a flange (8), a partly spherical portion (16) and a plurality of pistons (9), which are fixed to the flange (8). The device (1) also has a plurality of cylindrical sleeves (11), wherein each sleeve (11) has a sleeve bottom (13) comprising a sleeve opening (14) including a centreline (23). The sleeves (11) cooperate with the pistons (9) to form respective compression chambers (12) of variable volume. A barrel plate (15) is mounted on the partly spherical portion (16) and has barrel plate ports (21) including respective centrelines (22). The sleeves (11) are rotatable about a second axis of rotation (19) which intersects the first axis of rotation (4) by an acute swash angle.

Abstract: A hydraulic device includes a shaft mounted in a housing rotatable about a first axis of rotation. The shaft has a flange extending perpendicularly to the first axis. A plurality of pistons is fixed to the flange. A plurality of cylindrical sleeves cooperates with the pistons to form respective compression chambers of variable volume. The cylindrical sleeves are rotatable about a second axis of rotation which intersects the first axis of rotation by an acute angle such that upon rotating the shaft the volumes of the compression chambers change. Each piston has a piston head including a circumferential wall of which the outer side is ball-shaped and the inner side surrounds a cavity. Each of the pistons is fixed to the flange by a piston pin having a piston pin head including a circumferential outer side facing the inner side of the circumferential wall of the piston head.

Abstract: A hydraulic swash block positioning system for positioning a swash block to set a variable displacement, the hydraulic device including a rotor with pistons and piston chambers, the positioning system having, between the housing and the swash block, a positioning cylinder with a positioning piston forming a positioning chamber for setting an average value of the swash block position and a control valve connecting the high oil pressure source with the positioning chamber through a feeding line. In accordance with the invention the feeding line is connected to an oil container that has a variable container volume that can be adjusted synchronously with the changes in the number of piston chambers connected to the high oil pressure source.

Abstract: A hydraulic device (1) comprises a housing (27), a shaft (2) which is mounted in the housing (27) and rotatable about a first axis of rotation (4), wherein the shaft (2) has a flange (8) extending perpendicularly to the first axis (4), a plurality of pistons (9) which are fixed to the flange (8) at equiangular distance about the first axis of rotation (4), and a plurality of cylindrical sleeves (10) cooperating with the pistons (9) to form respective compression chambers (11) of variable volume. The sleeves (10) are rotatable about a second axis of rotation which intersects the first axis of rotation (4) by an acute angle such that upon rotating the shaft (2) the volumes of the compression chambers (11) change. Each piston (9) has a piston head (14) including a ball-shaped circumferential outer side.

Abstract: A hydraulic device comprises a shaft mounted in a housing rotatable about a first axis. A plurality of pistons are fixed to a flange rotatable about a first axis. A plurality of cylindrical sleeves sleeve bottoms and sleeve jackets that cooperate with the pistons to form compression chambers. Rotation of the shaft causes the volumes of the compression chambers. Each piston head forms a sealing line within the cooperating sleeve jacket. Each sleeve jacket has a thin wall and/or is elastically movable with respect to the sleeve bottom such that at a fixed pressure the radial deformation of the sleeve jacket at the sealing line is substantially constant at piston positions ranging from bottom dead center to a position where the distance between the sleeve bottom and the sealing line is less than 50% of the distance between the sleeve bottom and the sealing line at bottom dead center.

Abstract: A hydraulic device comprises a housing, a shaft rotatable about a first axis of rotation and a flange. A plurality of cylindrical sleeves cooperate with a plurality of pistons on the flange to form compression chambers, wherein the cylindrical sleeves are rotatable about a second axis of rotation which intersects the first axis of rotation by an acute angle such that upon rotating the shaft the volumes of the compression chambers change. A barrel plate is rotatable about the second axis has a first side for supporting the cylindrical sleeves. An opposite second side is supported by a supporting surface of a plate-shaped face element which is fixed to the housing. The supporting surface lies in a first plane. The face element has a back side that lies in a second plane, which forms an angle with the first plane that is smaller than said acute angle.

Abstract: A hydraulic device (1) comprises a housing (2) and a shaft (3) which is rotatable about a first axis of rotation (4). The shaft (3) has a flange (8), a partly spherical portion (16) and a plurality of pistons (9), which are fixed to the flange (8). The device (1) also has a plurality of cylindrical sleeves (11), wherein each sleeve (11) has a sleeve bottom (13) comprising a sleeve opening (14) including a centreline (23). The sleeves (11) cooperate with the pistons (9) to form respective compression chambers (12) of variable volume. A barrel plate (15) is mounted on the partly spherical portion (16) and has barrel plate ports (21) including respective centrelines (22). The sleeves (11) are rotatable about a second axis of rotation (19) which intersects the first axis of rotation (4) by an acute swash angle.

Abstract: A hydraulic device (1) comprises a housing (27), a shaft (2) which is mounted in the housing (27) and rotatable about a first axis of rotation (4), wherein the shaft (2) has a flange (8) extending perpendicularly to the first axis (4), a plurality of pistons (9) which are fixed to the flange (8) at equiangular distance about the first axis of rotation (4), and a plurality of cylindrical sleeves (10) cooperating with the pistons (9) to form respective compression chambers (11) of variable volume. The sleeves (10) are rotatable about a second axis of rotation which intersects the first axis of rotation (4) by an acute angle such that upon rotating the shaft (2) the volumes of the compression chambers (11) change. Each piston (9) has a piston head (14) including a ball-shaped circumferential outer side.

Abstract: A hydraulic device includes a shaft mounted in a housing rotatable about a first axis of rotation. The shaft has a flange extending perpendicularly to the first axis. A plurality of pistons is fixed to the flange. A plurality of cylindrical sleeves cooperates with the pistons to form respective compression chambers of variable volume. The cylindrical sleeves are rotatable about a second axis of rotation which intersects the first axis of rotation by an acute angle such that upon rotating the shaft the volumes of the compression chambers change. Each piston has a piston head including a circumferential wall of which the outer side is ball-shaped and the inner side surrounds a cavity. Each of the pistons is fixed to the flange by a piston pin having a piston pin head including a circumferential outer side facing the inner side of the circumferential wall of the piston head.

Abstract: A hydraulic device comprises a housing, a shaft rotatable about a first axis of rotation and a flange. A plurality of cylindrical sleeves cooperate with a plurality of pistons on the flange to form compression chambers, wherein the cylindrical sleeves are rotatable about a second axis of rotation which intersects the first axis of rotation by an acute angle such that upon rotating the shaft the volumes of the compression chambers change. A barrel plate is rotatable about the second axis has a first side for supporting the cylindrical sleeves. An opposite second side is supported by a supporting surface of a plate-shaped face element which is fixed to the housing. The supporting surface lies in a first plane. The face element has a back side that lies in a second plane, which forms an angle with the first plane that is smaller than said acute angle.

Abstract: A hydraulic device comprises a shaft mounted in a housing rotatable about a first axis. A plurality of pistons are fixed to a flange rotatable about a first axis. A plurality of cylindrical sleeves sleeve bottoms and sleeve jackets that cooperate with the pistons to form compression chambers. Rotation of the shaft causes the volumes of the compression chambers. Each piston head forms a sealing line within the cooperating sleeve jacket. Each sleeve jacket has a thin wall and/or is elastically movable with respect to the sleeve bottom such that at a fixed pressure the radial deformation of the sleeve jacket at the sealing line is substantially constant at piston positions ranging from bottom dead center to a position where the distance between the sleeve bottom and the sealing line is less than 50% of the distance between the sleeve bottom and the sealing line at bottom dead center.

Abstract: A hydraulic swash block positioning system for positioning a swash block to set a variable displacement, the hydraulic device including a rotor with pistons and piston chambers, the positioning system having, between the housing and the swash block, a positioning cylinder with a positioning piston forming a positioning chamber for setting an average value of the swash block position and a control valve connecting the high oil pressure source with the positioning chamber through a feeding line. In accordance with the invention the feeding line is connected to an oil container that has a variable container volume that can be adjusted synchronously with the changes in the number of piston chambers connected to the high oil pressure source.

Abstract: The invention is related to a hydraulic device comprising a housing including pipe ports, a rotor (14) having rotor chambers (9) which are formed by a cylinder (11) and a piston (12) which rotate about a first axis of rotation (m1) and a second axis of rotation (m2). Both axes of rotation extend within a common plane and intersect each other. A face plate (4) including a face plate centre line which coincides with the second axis of rotation (ml) has two or more face plate ports (3) which are each communicating with a pipe port for communicating the pipe port with the rotor chambers (9). An adjustment device adjusts the mutual positions of the face plate (4) and the common plane. Corresponding to the invention a face plate bearing (30, 32) between the face plate (4) and the housing has at least two axes of rotation which intersect the face plate centre line preferably perpendicularly and upon rotating the face plate (4) the common plane rotates with respect to the housing.

Abstract: An axial bearing between a first part and a second part that presses with an axial load against the first part and can rotate around a rotation axis relative to the first part comprising a circular or arc-shaped ridge on the first part centered around the rotation axis, a pressure source for providing pressurized hydraulic fluid on a first side of the circular or arc-shaped ridge, an adjustable gap between the circular or arc shaped ridge and a bearing surface on the second part, wherein the pressurized hydraulic fluid flows through the adjustable gap to a second side of the circular or arc-shaped ridge. In accordance with the invention the circular or arc-shaped ridge or the bearing surface include a ridge chamber for locally creating a larger adjustable gap between the circular or arc-shaped ridge and the bearing surface.

Abstract: The invention relates to a hydraulic drive system for driving hydromotors. The hydromotors may be loaded with variable loads and are coupled via hydraulic transformers with the pressure conduit which is substantially maintained at a constant pressure by means of a pump. The pump is provided with switch means by which the delivery of the pump can be alternately activated and inactivated, allowing of the pump's delivery to be varied quickly.

Abstract: A free piston combustion engine and method by which additional combustion air is supplied by a charge air system. The charge air system includes a piston-cylinder charge air pump in which the piston is movable independently of the movement of the free piston. The charge air pump may be hydraulically driven.

Abstract: A hydraulic system includes a hydraulic transformer with a rotor which is coupled with the hydromotor. The hydromotor may be subjected to a variable load which has to be moved in different directions. By using various switching means, the combination hydromotor and hydraulic transformer has been made suitable for the necessary four-quadrant operation.

Abstract: An hydraulic switching valve (35) comprises, among other parts, a valve housing (45, 62) with a first connection (33, 36) and a second connection (34, 67) and a valve body (37, 63) which is movable in the valve housing (45). The switching valve (35) is open when the pressure at the first connection (33) is higher than the pressure at the second connection (34) as a result of the fact that the pressure difference caused by the movement of the valve body (37) allows a flow past the valve body (37). The switching valve is closed when the pressure at the first connection (33) is lower than the pressure at the second connection (34) as a result of the fact that the movement of the valve body (37) caused by the pressure difference closes a valve seal (40) which blocks the flow. The switching valve (35) further comprises a lock (39) with switching element (42) for selectively keeping the valve seal (40) closed, and unblocking the valve body (37), respectively.

Abstract: A free-piston engine comprises a combustion part (1), a hydraulic control system (2), an energy consumption system and an engine control system. The combustion part comprises a combustion cylinder with at least one combustion piston (4). The hydraulic control system (2) comprises a hydraulic piston (24) which, together with a combustion piston (4), forms a piston assembly, and which has a first surface that, when under hydraulic pressure, exerts a force on the piston assembly (24) that is directed towards the combustion space (6) and a second surface, smaller than the first surface, that, when under hydraulic pressure, exerts a force on the piston assembly that is directed away from the combustion space.