A hydrodynamic machine has a working chamber that may be filled with a working medium and in which a bladed pump impeller and a bladed turbine impeller are arranged to hydrodynamically transmit torque and/or drive power from the pump impeller to the turbine impeller. A working medium inlet and a working medium outlet are provided for inputting and discharging the working medium in/out of the working chamber. A control valve is furnished in the working medium inlet or in a bypass. The control valve changes the working medium quantity flowing into the working chamber. The control valve is connected to the working medium inlet and/or the working medium outlet and actuated such that the flow cross-section of the control valve is variably adjusted as a function of the working medium pressure in the working medium inlet and as a function of the working medium pressure in the working medium outlet.

A hydrodynamic machine has a working chamber that may be filled with a working medium and in which a bladed pump impeller and a bladed turbine impeller are arranged to hydrodynamically transmit torque and/or drive power from the pump impeller to the turbine impeller. A working medium inlet and a working medium outlet are provided for inputting and discharging the working medium in/out of the working chamber. A control valve is furnished in the working medium inlet or in a bypass. The control valve changes the working medium quantity flowing into the working chamber. The control valve is connected to the working medium inlet and/or the working medium outlet and actuated such that the flow cross-section of the control valve is variably adjusted as a function of the working medium pressure in the working medium inlet and as a function of the working medium pressure in the working medium outlet.

A construction machine having a frame and at least one compaction member is provided. The machine also includes a propulsion system having a hydraulic motor adapted to rotate the compaction member. The propulsion system also includes a hydraulic pump fluidly coupled to the hydraulic motor via a high pressure line and a low pressure line. The high pressure line allows flow of a fluid at high pressure from the hydraulic pump to the hydraulic motor. The low pressure line allows flow of the fluid at low pressure from the hydraulic motor to the hydraulic pump. The propulsion system further includes a hydraulic valve fluidly coupled to the low pressure line and a casing of the hydraulic motor. The hydraulic valve selectively allows flow of a portion of the fluid at low pressure from the low pressure line to the casing for cooling of the hydraulic motor.

A construction machine having a frame and at least one compaction member is provided. The machine also includes a propulsion system having a hydraulic motor adapted to rotate the compaction member. The propulsion system also includes a hydraulic pump fluidly coupled to the hydraulic motor via a high pressure line and a low pressure line. The high pressure line allows flow of a fluid at high pressure from the hydraulic pump to the hydraulic motor. The low pressure line allows flow of the fluid at low pressure from the hydraulic motor to the hydraulic pump. The propulsion system further includes a hydraulic valve fluidly coupled to the low pressure line and a casing of the hydraulic motor. The hydraulic valve selectively allows flow of a portion of the fluid at low pressure from the low pressure line to the casing for cooling of the hydraulic motor.

A hydrodynamic machine contains a bladed primary wheel driven by a rotary shaft and a bladed secondary wheel, which together form a work chamber filled with a working medium. The machine has a pressure pump for delivering a working medium from the work chamber. The pressure pump has a first inlet, which projects into the work chamber, and has a first inlet opening which is aligned with the rotary shaft in the circumferential direction. The pressure pump has a second inlet which projects into the work chamber and has a second inlet opening which is aligned to the rotary shaft in the circumferential direction opposite to the first inlet opening. The first and second inlets are joined to a common working medium channel behind the two inlet openings. The first and second inlets extend adjacent to each other in the same flow direction separated by a separation wall.

A hydrodynamic machine contains a bladed primary wheel driven by a rotary shaft and a bladed secondary wheel, which together form a work chamber filled with a working medium. The machine has a pressure pump for delivering a working medium from the work chamber. The pressure pump has a first inlet, which projects into the work chamber, and has a first inlet opening which is aligned with the rotary shaft in the circumferential direction. The pressure pump has a second inlet which projects into the work chamber and has a second inlet opening which is aligned to the rotary shaft in the circumferential direction opposite to the first inlet opening. The first and second inlets are joined to a common working medium channel behind the two inlet openings. The first and second inlets extend adjacent to each other in the same flow direction separated by a separation wall.

A system comprising a discharge valve that allows some of the fluid generated by a fluid generating source and intended for a drive torque generating member for a rotary element of a mechanical device to be removed so as to limit the corresponding rotational speed, this being done for a length of time that allows a thermal gradient to be reduced sufficiently that a phenomenon of deformation of said rotary element can be prevented.

A system comprising a discharge valve that allows some of the fluid generated by a fluid generating source and intended for a drive torque generating member for a rotary element of a mechanical device to be removed so as to limit the corresponding rotational speed, this being done for a length of time that allows a thermal gradient to be reduced sufficiently that a phenomenon of deformation of said rotary element can be prevented.

A hydrodynamic machine contains a bladed primary wheel driven by a rotary shaft and a bladed secondary wheel, which together form a work chamber filled with a working medium. The machine has a pressure pump for delivering a working medium from the work chamber. The pressure pump has a first inlet, which projects into the work chamber, and has a first inlet opening which is aligned with the rotary shaft in the circumferential direction. The pressure pump has a second inlet which projects into the work chamber and has a second inlet opening which is aligned to the rotary shaft in the circumferential direction opposite to the first inlet opening. The first and second inlets are joined to a common working medium channel behind the two inlet openings. The first and second inlets extend adjacent to each other in the same flow direction separated by a separation wall.

A hydrodynamic machine contains a bladed primary wheel driven by a rotary shaft and a bladed secondary wheel, which together form a work chamber filled with a working medium. The machine has a pressure pump for delivering a working medium from the work chamber. The pressure pump has a first inlet, which projects into the work chamber, and has a first inlet opening which is aligned with the rotary shaft in the circumferential direction. The pressure pump has a second inlet which projects into the work chamber and has a second inlet opening which is aligned to the rotary shaft in the circumferential direction opposite to the first inlet opening. The first and second inlets are joined to a common working medium channel behind the two inlet openings. The first and second inlets extend adjacent to each other in the same flow direction separated by a separation wall.