A hydraulic device having a plurality of cylinders for distributing a flow of hydraulic fluid between a reservoir and a load, the device comprising: a housing having the plurality of cylinders with a plurality of corresponding pistons configured for reciprocation of a constant stroke length; an input port of the housing fluidly connected to each cylinder of the plurality of cylinders, the input port facilitating introduction of the hydraulic fluid into said each cylinder; an output port of the housing connected to said each cylinder, the output port facilitating the ejection of the hydraulic fluid from said each cylinder during the reciprocation, the output port configured for fluidly coupling said each cylinder to the load; and a distributor coupled to a main shaft of the hydraulic device, such that the distributor rotates in conjunction with the main shaft, the distributor having a distributor body including a first port configured for fluid communication with the input port and a second port configured for fluid communication with the output port; wherein the first port and the second port are fluidly coupled to the input port and the output port external to a shaft body of the main shaft.

A hydraulic device having a plurality of cylinders for distributing a flow of hydraulic fluid between a reservoir and a load, the device comprising: a housing having the plurality of cylinders with a plurality of corresponding pistons configured for reciprocation of a constant stroke length; an input port of the housing fluidly connected to each cylinder of the plurality of cylinders, the input port facilitating introduction of the hydraulic fluid into said each cylinder; an output port of the housing connected to said each cylinder, the output port facilitating the ejection of the hydraulic fluid from said each cylinder during the reciprocation, the output port configured for fluidly coupling said each cylinder to the load; and a distributor coupled to a main shaft of the hydraulic device, such that the distributor rotates in conjunction with the main shaft, the distributor having a distributor body including a first port configured for fluid communication with the input port and a second port configured for fluid communication with the output port; wherein the first port and the second port are fluidly coupled to the input port and the output port external to a shaft body of the main shaft.

An axial piston machine may include a housing, a guide, a shaft, at least two cylinders each delimited by an associated cylinder wall, at least two pistons, a feed configured to supply a working fluid, an exhaust configured to discharge the working fluid, and at least one actuator configured to open and close a plurality of secondary outlets. Each associated cylinder wall may include a primary outlet and a secondary outlet of the plurality of secondary outlets. Each primary outlet and each secondary outlet may be fluidically connected to an outlet chamber that is fluidically connected to the exhaust. Each primary outlet may open into an associated primary outlet channel that opens into the outlet chamber. Each secondary outlet may be fluidically connected to an associated secondary outlet channel that opens into the outlet chamber and is separate from the plurality of primary outlet channels.

A variable displacement pump-motor includes a pump-motor having a plurality of cylinders and pistons, and further including a main shaft rotatable relative to the system body. A hydro mechanical control system includes a plurality of main stage valves in communication with the plurality of cylinders. Each of the main stage valves is configured to open and close a cylinder of the plurality of cylinders to one or more of high or low pressure fluid sources. A pilot spool valve is in selective communication with each of the main stage valves. The pilot spool rotates with the main shaft. The pilot spool includes coding configured to operate each of the main stage valves to open and close the respective cylinders to the one or more high and low pressure fluid sources according to a translational position of the pilot spool and rotation of the pilot spool by the main shaft.

An axial piston machine may include a housing, a guide, a shaft, at least two cylinders each delimited by an associated cylinder wall, at least two pistons, a feed configured to supply a working fluid, an exhaust configured to discharge the working fluid, and at least one actuator configured to open and close a plurality of secondary outlets. Each associated cylinder wall may include a primary outlet and a secondary outlet of the plurality of secondary outlets. Each primary outlet and each secondary outlet may be fluidically connected to an outlet chamber that is fluidically connected to the exhaust. Each primary outlet may open into an associated primary outlet channel that opens into the outlet chamber. Each secondary outlet may be fluidically connected to an associated secondary outlet channel that opens into the outlet chamber and is separate from the plurality of primary outlet channels.

A variable displacement pump-motor includes a pump-motor having a plurality of cylinders and pistons, and further including a main shaft rotatable relative to the system body. A hydro mechanical control system includes a plurality of main stage valves in communication with the plurality of cylinders. Each of the main stage valves is configured to open and close a cylinder of the plurality of cylinders to one or more of high or low pressure fluid sources. A pilot spool valve is in selective communication with each of the main stage valves. The pilot spool rotates with the main shaft. The pilot spool includes coding configured to operate each of the main stage valves to open and close the respective cylinders to the one or more high and low pressure fluid sources according to a translational position of the pilot spool and rotation of the pilot spool by the main shaft.

A hydraulic actuation unit for controlling the starting and stopping of hydraulic motors includes a first main circuit and a second main circuit, a first recirculation circuit and a second recirculation circuit, a counterbalancing valve, which includes a shuttle, and a first discharge channel and a second discharge channel. The shuttle includes a first check valve and a second check valve. The first check valve includes at least one first flow control element that can move from an open position to a closure position. The second check valve includes at least one second flow control element that can move from an open position to a closure position. The first and second check valves respectively are provided with first damping means and second damping means in order to slow down the passage movement respectively of the first flow control element and of the second flow control element.