DE102013225567A1 - Hydraulic hybrid system - Google Patents

Abstract

Hydraulic hybrid system (1) for a motor vehicle with an internal combustion engine (18), comprising a hydraulic high pressure motor (3, 4) as a hydraulic machine (3, 4) for converting hydraulic energy into mechanical energy, a hydraulic high pressure pump (5, 6) as Hydraulic machine (5, 6) for converting mechanical energy into hydraulic energy, in that a hydraulic fluid can be conveyed by the hydraulic pump, a pressure accumulator (7, 8, 9) for storing hydraulic energy, the high-pressure pump (5, 6) and the high-pressure motor (3, 4) is formed by an identical hydraulic machine (3, 4, 5, 6) and the hydraulic machine (3, 4, 5, 6) comprises at least one movable working member and at least one variable-volume working space, wherein the hydraulic machine (3, 4, 5, 6) per working space, a low-pressure valve with a LP actuator for opening and closing the low-pressure valve and a high-pressure valve with a HD Aktu ator for opening and closing the high-pressure valve comprises for introducing and removing the hydraulic fluid in and out of the working space.

Description

The present invention relates to a hydraulic hybrid system according to the preamble of claim 1, an internal combustion engine system according to the preamble of claim 7 and a method for operating a hydraulic hybrid system and an internal combustion engine system according to the preamble of claim 8.

State of the art

In high-pressure injection systems for internal combustion engines, in particular in common-rail injection systems of diesel or gasoline engines, a high-pressure pump continuously ensures the maintenance of the pressure in the high-pressure accumulator of the common-rail injection system. The high-pressure pump can be driven, for example, by a camshaft of the internal combustion engine by means of a drive shaft. For the promotion of the fuel to the high-pressure pump Vorförderpumpen, z. B. a gear or rotary vane pump used, which are connected upstream of the high-pressure pump. The prefeed pump delivers the fuel from a fuel tank through a fuel line to the high pressure pump. Amongst others, piston pumps are used as high-pressure pumps.

Automobiles with a hydraulic hybrid system include a hydraulic motor for converting hydraulic energy to mechanical energy, a hydraulic pump for converting mechanical energy to hydraulic energy, and a pressure accumulator for storing hydraulic energy. Mechanical energy, for example from an internal combustion engine or in a recuperation operation, the kinetic energy of the motor vehicle can be used with the hydraulic hybrid system to increase the pressure of hydraulic fluid in a pressure accumulator, in particular in a high-pressure accumulator, in order to store hydraulic energy in the high-pressure accumulator , For this reason, it is necessary to provide on the motor vehicle with the hydraulic hybrid system both a separate hydraulic motor and a separate hydraulic pump and the pressure accumulator. The hydraulic pump is used to convert mechanical energy, eg. As the internal combustion engine, in hydraulic energy, d. H. to increase the pressure in the accumulator. However, additional components on the motor vehicle lead to an additional space requirement and higher costs and also to a higher weight on the motor vehicle in a disadvantageous manner.

From the WO 2010/069857 A1 a hybrid drive system is known with an internal combustion engine, which is operated with fuel from a fuel tank and with a hydraulic machine, which cooperates with a hydraulic energy accumulator, wherein the hydraulic machine is operated with the same fuel with which the internal combustion engine is operated.

From the DE 10 2013 204 025 a hybrid hydraulic system for a motor vehicle is known. The hydraulic hybrid system comprises a hydraulic motor, a hydraulic pump and a pressure accumulator with which hydraulic energy can be stored under high pressure and used as mechanical energy. The hydraulic motor and the hydraulic pump are formed by an identical hydraulic machine.

Disclosure of the invention

Advantages of the invention

A hybrid system according to the invention for a motor vehicle having an internal combustion engine, comprising a hydraulic high-pressure motor as a hydraulic machine for converting hydraulic energy into mechanical energy, a hydraulic high-pressure pump as a hydraulic machine for converting mechanical energy into hydraulic energy, in that a hydraulic fluid can be conveyed by the hydraulic pump, a pressure accumulator for storing hydraulic energy, wherein the high-pressure pump and the high-pressure motor is formed by an identical hydraulic machine and the hydraulic machine comprises at least one movable working member and at least one variable-volume working space, wherein the hydraulic machine per working space a low-pressure valve with a ND Actuator for opening and closing the low-pressure valve and a high-pressure valve with a high-pressure actuator for opening and closing the high-pressure valve comprises for introducing and removing the hydrau Liquids in and out of the work area. At the working space of the hydraulic machines, a low pressure valve with the LP actuator and a high pressure valve with the HP actuator is arranged. The low and high pressure valve can thus be actively opened and closed by a control unit. This makes it possible in an advantageous manner that the hydraulic machine with the movable working member and the variable-volume working space both as High pressure motor as well as a high pressure pump can be used. The working member can thus convert both hydraulic energy into mechanical energy as a high pressure motor and high pressure pump to convert mechanical energy into hydraulic energy. With a low design effort, ie the provision of hydraulic machines with actively controllable high and low pressure valves, this can thus be used both as a high pressure motor and as a high pressure pump and work.

In particular, the hydraulic hybrid system, in particular the hydraulic machine, comprises a control unit, and the control unit controls the opening and closing of the at least one low-pressure valve and the at least one high-pressure valve.

In a further embodiment, the movable at least one working member, in particular a working piston, indirectly supported on a rotating drive shaft, and on the at least one working member is applied by an elastic element, in particular a spring, a force, in particular compressive force, directly or indirectly such that a rotational movement of the drive shaft causes an oscillating movement of the at least one working member and / or the at least one working member is movable between a top dead center with a minimum volume of the associated working space and a bottom dead center with a maximum volume of the associated working space and / or at least one low-pressure valve each comprises a valve piston which is movable by the LP actuator, and the at least one high-pressure valve each comprises a valve piston which is movable by the HP actuator and / or the at least one LP actuator is an electromagnet or an H. ydraulikaktuator is formed and the at least one HD actuator formed by an electromagnet or a Hydraulikaktuator.

In a supplementary embodiment, the hydraulic machine comprises a rotation angle sensor for detecting a rotational angular position of the drive shaft and, depending on the rotational angular position of the drive shaft, the opening and closing of the at least one low-pressure valve and the at least one high-pressure valve is controllable.

In an additional embodiment, the opening and closing of the at least one low-pressure valve and the at least one high-pressure valve can be controlled as a function of the volume flow of hydraulic fluid to be conducted by the hydraulic machine and / or controllable as a high-pressure pump or as a high-pressure motor depending on the operating mode.

Preferably, the at least one high pressure valve and the at least one low pressure valve of the hydraulic machine are controlled as a high pressure pump to the effect that during movement of the at least one working member from the bottom dead center to the top dead center, the at least one high pressure valve is open and the at least one low pressure valve is closed and a movement of the at least one working member from the top dead center to the bottom dead center, the at least one high pressure valve is closed and the at least one low pressure valve is open and / or the at least one high pressure valve and the at least one low pressure valve of the hydraulic machine are controlled as a high pressure motor, during a movement of the at least one working member from the bottom dead center to the top dead center, the at least one high-pressure valve is closed and the at least one low-pressure valve is open and during a movement of the at least one working member from the top dead center to the bottom dead center, the at least one high pressure valve is opened and the at least one low pressure valve is closed.

In one variant is used as a hydraulic fluid for storing hydraulic energy fuel, especially diesel, the internal combustion engine, in particular exclusively fuel is used as hydraulic fluid and / or in an open high-pressure valve, the working space in fluid communication with at least one injector and / or a high-pressure accumulator and In the case of an open low-pressure valve, the working space is in fluid-conducting connection with a low-pressure accumulator, in particular a fuel tank.

Inventive internal combustion engine system for a motor vehicle, comprising a high pressure injection system with an injector high pressure pump, preferably a high pressure rail, preferably a prefeed pump for conveying a fuel from a fuel tank to the injector high pressure pump, preferably a drive train for driving drive wheels of the motor vehicle with an internal combustion engine and / or a hydraulic Engine, a hybrid hydraulic system having a high pressure hydraulic motor for converting hydraulic energy to mechanical energy, a high pressure hydraulic pump for converting mechanical energy to hydraulic energy, a pressure accumulator for storing hydraulic energy, the hybrid hydraulic system being a hydraulic hybrid system as described in this patent application is formed and / or the injector high pressure pump is formed by the high-pressure pump.

Inventive method for operating a hydraulic hybrid system, in particular a hydraulic hybrid system described in this patent application, and / or an internal combustion engine system, in particular one described in this patent application Internal combustion engine system, comprising the steps of: conveying hydraulic fluid from a low-pressure accumulator to a high-pressure accumulator with a hydraulic pump, so that mechanical energy is converted into hydraulic energy by the hydraulic pump, passing the hydraulic fluid from the high-pressure accumulator to the low-pressure accumulator and by a hydraulic motor; that in the hydraulic motor hydraulic energy is converted into mechanical energy and the mechanical energy is used to drive the motor vehicle, the hydraulic pump as a high-pressure pump and the hydraulic motor as a high-pressure motor are formed by an identical hydraulic machine and on the identical hydraulic machine at least one Moving member is moved so that the volume of the at least one working member associated working space is changed.

The hydraulic machine per working space expediently comprises a low-pressure valve with an LP actuator for opening and closing the low-pressure valve and a high-pressure valve with a high-pressure actuator for opening and closing the high-pressure valve for introducing and discharging the hydraulic fluid into and out of the working space and / or Hydraulic fluid, in particular exclusively, fuel, preferably diesel, the internal combustion engine is used, in particular the fuel is conveyed by the hydraulic machine as a high pressure pump to the high pressure accumulator and / or is promoted by the hydraulic machine as injector high pressure pump to at least one injector of the internal combustion engine and / or at least one high pressure valve of the hydraulic machine is brought by a high pressure fuel line in fluid communication with at least one injector of the internal combustion engine and / or to a high pressure accumulator and / or the at least one low pressure Valve is brought into fluid communication with a fuel line to a fuel tank and / or the at least one working member, in particular a working piston, is moved, in particular with a drive shaft, between a top dead center and a bottom dead center.

In a further embodiment, during operation of the hydraulic machine as a high pressure pump during movement of the at least one working member from bottom dead center to top dead center, the at least one high pressure valve is opened and the at least one low pressure valve is closed and a drive shaft applies force to the at least one Operating member transmitted to move the working member from the bottom dead center to the top dead center against the pressure applied by the hydraulic fluid to the working member pressing force, so that mechanical energy is converted into hydraulic energy and the hydraulic fluid is conveyed out of the at least one working space and during movement of the at least one Arbeitsorganes from the top dead center to the bottom dead center, the at least one high-pressure valve is closed and the at least one low-pressure valve is open, so that the hydraulic fluid in the Arbeitsr is promoted into it.

In particular, during operation of the hydraulic machine as a high pressure motor during movement of the at least one working member from top dead center to bottom dead center, the at least one high pressure valve is opened and the at least one low pressure valve is closed and the pressurizing force applied to the working fluid by the hydraulic fluid is applied to a drive shaft so that hydraulic energy is converted into mechanical energy and the hydraulic fluid is delivered into the at least one working space and during movement of the at least one working member from bottom dead center to top dead center, the at least one high pressure valve is closed and that is at least one low pressure valve opened, so that the hydraulic fluid is conveyed out of the work area.

In a further embodiment, during operation of the hydraulic machine as a high pressure motor during movement of the at least one working member from top dead center to bottom dead center, the at least one high pressure valve is opened and the at least one low pressure valve is closed and closed during movement of the at least one working member from the top Dead center to the bottom dead center, the high pressure valve is closed, so that the inflow of the hydraulic fluid is interrupted in the working space and the sooner the high pressure valve is closed, the less hydraulic energy is converted into mechanical energy and vice versa.

In a supplementary variant, during operation of the hydraulic machine as a high pressure motor during movement of the at least one working member from top dead center to bottom dead center after closing or closing, or shortly before closing the high pressure valve, the low pressure valve is opened to provide a high pressure reduction to avoid the work space.

In a further variant, during operation of the hydraulic machine as a high-pressure motor during a movement of the at least one working member from the bottom dead center to the top dead center, the at least one high-pressure valve is fired and the at least one Low pressure valve is initially opened and closed before top dead center, so that during the movement of the at least one working member from the bottom dead center to the top dead center, the pressure in the working chamber due to the closed high and low pressure valve increases and at top dead center, a smaller pressure difference between working space and a high pressure line, particularly high pressure fuel line, is present at the high pressure valve as without closing the at least one low pressure valve before top dead center and the HP actuator thereby requires less force to open the valve piston of the high pressure valve due to the smaller pressure difference.

In a further embodiment, during operation of the hydraulic machine as a high-pressure pump during a movement of the at least one working member from the bottom dead center to the top dead center, the at least one high-pressure and low-pressure valve are closed in an initial phase of the movement of the working member, so that the pressure in the working space increases and thereby a smaller pressure difference between the working space and a high pressure line, in particular high pressure fuel line, is present at the high pressure valve than without an initial closing of the high pressure valve and only after the initial phase of movement of the at least one working member only the high pressure valve is opened and thereby the high pressure actuator a small force needed to open the valve piston of the high pressure valve due to the smaller pressure difference.

In particular, the high pressure pump is designed such that from the high pressure pump, the pressure of the hydraulic fluid at a pressure of at least 200 bar, 500 bar, 1000 bar or 2000 bar can be increased to convert mechanical energy into hydraulic energy and / or the high pressure motor is designed to that hydraulic fluid with a pressure of at least 200 bar, 500 bar, 1000 bar or 2000 bar can be processed to convert hydraulic energy into mechanical energy.

In a supplementary embodiment is used as a hydraulic fluid for storing hydraulic energy fuel, especially diesel, the internal combustion engine, in particular, only fuel is used as the hydraulic fluid. Fuel, in particular diesel of an internal combustion engine as a diesel engine or gasoline of a gasoline engine as an internal combustion engine is constantly replaced due to the consumption of the fuel, so that no maintenance or replacement of the hydraulic fluid is required.

The pressure accumulator preferably comprises a high-pressure accumulator and a low-pressure accumulator and the low-pressure accumulator is formed by a fuel tank of the internal combustion engine. As a low-pressure accumulator, the fuel tank is used, so that thereby the already existing on the motor vehicle fuel tank can be used as a low-pressure accumulator for the hydraulic hybrid system. Advantageously, thereby no additional low-pressure accumulator for the hydraulic hybrid system is required.

In one variant, kinetic energy of the motor vehicle can be converted into mechanical energy in a recuperation operation by the high-pressure pump, since the high-pressure pump is mechanically connected to a drive wheel of the motor vehicle.

Suitably, the high pressure pump is also used as injector high pressure pump of a high pressure injection system Thus, both the high pressure pump and the high pressure motor and the injector high pressure pump can be provided with a single hydraulic machine. As a result, additional hydraulic machines can be saved on the hydraulic hybrid system in an advantageous manner, so that the hydraulic hybrid system in the production inexpensive, requires little space and also little mass on the motor vehicle in an advantageous manner.

In particular, the fuel tank of the internal combustion engine is used as a low pressure accumulator and / or in the high pressure hydraulic motor, the pressure of the hydraulic fluid is reduced by at least 100 bar, 300 bar, 600 bar, 1000 bar or 2000 bar and / or in the hydraulic pump, the pressure of the hydraulic fluid increased by at least 100 bar, 300 bar, 600 bar, 1000 bar or 2000 bar.

In a further embodiment, the pressure in the low-pressure accumulator, in particular the fuel tank, is less than 5 bar, 3 bar or 2 bar, in particular the pressure in the low-pressure accumulator as fuel tank is substantially 1 bar.

In a further variant, the hydraulic high-pressure pump is driven in a recuperation operation by a drive wheel of the motor vehicle, so that kinetic energy of the motor vehicle is converted into hydraulic energy in the pressure accumulator.

In another embodiment, fuel is directed from the high pressure accumulator into the high pressure rail and vice versa.

In one variant, the hybrid system includes a low pressure accumulator and a high pressure accumulator.

Suitably, the hydraulic fluid is gasoline as fuel.

In a further embodiment, the high-pressure hydraulic motor and the high-pressure hydraulic pump is designed as a piston pump, in particular the at least one piston is moved by a crank mechanism, a crankshaft, a camshaft or an eccentric shaft and the crank mechanism, the crankshaft, the camshaft or the eccentric shaft is of driven by the internal combustion engine.

In particular, the high-pressure accumulator is a bladder accumulator, a piston accumulator or a spring accumulator. In the bladder accumulator, a gas is disposed within an elastic bladder which is compressed upon introduction of hydraulic fluid into the bladder spoke and vice versa. The bubble of rubber or plastic is surrounded by hydraulic fluid within a storage enclosure. The hydraulic fluid is used to pressurize and pressure relief of the high-pressure accumulator and the energy storage takes place in the high-pressure accumulator.

In a further variant, the internal combustion engine system and / or the hydraulic hybridstem comprises the internal combustion engine and / or a mechanical drive train for mechanical transmission of power from the internal combustion engine and / or a hydraulic drive train with hydraulic high pressure motor for hydraulic power transmission to the at least one drive wheel of the motor vehicle.

In a further embodiment, the prefeed pump is a prefeed pump with an electric motor, so that the prefeed pump is driven by the electric motor and, in particular, the delivery rate of the prefeed pump can be controlled and / or regulated.

In a further variant, the piston of the hydraulic machine is supported indirectly with a roller or a bucket tappet on the drive shaft, for. B. a camshaft or eccentric shaft, the hydraulic machine.

Brief description of the drawings

In the following, an embodiment of the invention will be described in more detail with reference to the accompanying drawings. It shows:

1 a highly schematic view of a hydraulic hybrid system and an internal combustion engine system,

2 a cross section of a high pressure pump,

3 a section AA of the high pressure pump according to 2 a roller with roller shoe and a drive shaft,

4 a diagram of the pressure curve in a working space of a hydraulic machine as a high-pressure pump in which the abscissa is the rotational angle position φ of the drive shaft and plotted on the ordinate of the pressure p in the working space

5 a diagram of the pressure curve in the working space of the hydraulic machine as a high-pressure motor in which the abscissa, the rotational angle position φ of the drive shaft and the ordinate the pressure p in the working space is applied and

6 a further diagram of the pressure curve in the working space of the hydraulic machine as a high pressure motor in which the abscissa, the rotational angular position φ of the drive shaft and the ordinate of the pressure p in the working space is plotted.

Embodiments of the invention

An unillustrated motor vehicle has an internal combustion engine 18 as a diesel engine for driving the motor vehicle. The internal combustion engine 18 has four combustion engine pistons, not shown, with corresponding engine cylinders. Into the work spaces on the engine cylinders is through each one of four injectors 17 Diesel as fuel from a high-pressure rail 16 injected. In a fuel tank 10 Diesel is stored as fuel and with a pre-feed pump 11 the fuel is passing through a fuel feed line 13 and an injector high pressure pump 15 fed. From the injector high pressure pump 15 is the fuel, which from the pre-feed pump 11 under a pressure between 3 bar and 5 bar of the high-pressure injector pump 15 is fed, in the pressure greatly increased to a pressure range between 3000 bar and 4000 bar. The fuel under high pressure is from the injector high pressure pump 15 through a high pressure fuel line 33 the high-pressure rail 16 fed. With a pressure sensor 32 will the pressure in the high-pressure rail 16 detected and by means not shown data line of a control unit 30 an internal combustion engine system 2 fed. By means of a control of the of the injector high pressure pump 15 promoted volume flow of fuel through the High-pressure fuel line 33 can in the high-pressure rail 16 a substantially constant pressure between 3000 bar and 4000 bar are kept. The of the internal combustion engine 18 discharged mechanical energy is by means of a drive train 20 drive wheels 25 fed. By means of a drive train shaft 39 can the mechanical energy from the internal combustion engine 18 directly (not shown) a transmission 21 as well as from the transmission 21 a differential gear 23 be supplied. The differential gear 23 drives two wheel drive shafts 24 each with a drive wheel 25 at. In 1 and 2 is the drive shaft 12 represented and by means of the drive shaft 12 with cams 29 becomes the injector high pressure pump 15 from the internal combustion engine 18 mechanically driven. By means of a clutch 22 can the mechanical connection between the internal combustion engine 18 and the injector high pressure pump 15 be solved, wherein preferably the mechanical connection between the internal combustion engine 18 and the powertrain 20 with the driveline shaft 39 is preserved (not shown).

The motor vehicle, not shown, also has a hydraulic hybrid system 1 as part of an internal combustion engine system 2 on. From a hydraulic pump 5 as a high pressure pump 6 can remove fuel from the fuel supply line 13 as a fuel line 40 sucked in and through a high-pressure fuel line 34 a pressure accumulator 7 as a high-pressure accumulator 8th be supplied under a pressure of 3000 bar to 4000 bar. The hydraulic pump 5 is thus designed so that this as a high pressure pump 6 can be used, ie the fuel as the hydraulic fluid of the hydraulic hybrid system 1 increased to a pressure of more than 3000 bar to 4000 bar. Furthermore, the hydraulic hybrid system 1 a hydraulic engine 3 as a high pressure motor 4 on. With the high pressure pump 6 can mechanical energy of the internal combustion engine 18 or in a Rekuperationsbetrieb kinetic energy of the motor vehicle are converted into hydraulic energy by the hydraulic fluid, ie the fuel as diesel fuel in the high-pressure accumulator 8th is encouraged. By passing fuel from the high pressure accumulator 8th in the hydraulic engine 3 as a high pressure motor 4 Hydraulic energy can be converted into mechanical energy. The fuel as diesel is thus through the high pressure fuel line 34 from the high pressure accumulator 8th the high-pressure engine 4 supplied and in the high pressure motor 4 the pressure of the diesel is greatly reduced, for. B. from 4000 bar to a pressure between 1 bar and 2 bar. This pressure reduction can release hydraulic energy and this is from the high pressure motor 4 converted into mechanical energy and thereby the drive train shaft 39 driven and thus the drive wheels 25 for driving the motor vehicle. After passing the diesel through the high-pressure fuel line 34 and the high-pressure engine 4 the diesel gets through a fuel return line 14 as a fuel line 40 with a very low pressure between 1 bar and 2 bar back to the fuel tank 10 fed so that the fuel tank 10 also as low-pressure storage 9 of the hydraulic hybrid system 1 serves. The high pressure pump 6 and the high-pressure engine 4 are from the same or identical hydraulic machine 4 . 6 formed and have at least one working organ 26 ie a working piston 27 , on. The working piston 27 is doing both in the high pressure pump 6 to increase the pressure, ie to convey the fuel through the high pressure fuel line 34 in the high-pressure accumulator 8th used as well as for the conversion of hydraulic energy into mechanical energy by the diesel through the high pressure fuel line 34 through a workroom 28 on the working piston 27 back into the fuel return line 14 is initiated.

In the high pressure fuel line 33 is a valve 36 installed, in the high pressure fuel line 34 a valve 38 and with a high pressure fuel connection pipe 35 is the high pressure fuel line 33 with the high pressure fuel line 34 connected. In the high pressure fuel connection pipe 35 is an additional valve 37 built-in. The valves 36 . 37 . 38 are by means not shown data lines with the control unit 30 connected. Furthermore, the feed pump is also 11 by means of appropriate data lines with the control unit 30 connected. By opening and closing the valves accordingly 36 . 37 . 38 and control of the injector high pressure pump 15 the high-pressure rail 16 supplied volume flow of fuel and by the high-pressure fuel line 34 Guided volume flow of fuel in both directions can thus be controlled and / or regulated, which volume flow of fuel to the high-pressure rail 16 and / or the high-pressure accumulator 8th supplied and / or can be supplied and / or from the high-pressure accumulator 8th in the fuel tank 10 is initiated and / or from the high-pressure accumulator 8th in the high-pressure rail 16 is initiated and / or vice versa.

The high pressure pump 6 , the high-pressure engine 4 as well as the injector high pressure pump 15 are formed by an identical hydraulic machine, so that the working piston 27 at the workrooms 28 both for delivering fuel to the high pressure rail 16 as well as in the high-pressure accumulator 8th are used as well as for conducting fuel from the high-pressure accumulator 8th through the high pressure motor 4 to the fuel tank 10 as a low-pressure accumulator 9 for converting hydraulic energy into mechanical energy.

From the control unit 30 Thus, different operating conditions of the hydraulic hybrid system 1 and / or the internal combustion engine system 2 to be controlled. For example, in an operating mode to store only hydraulic energy from the high pressure pump 6 , which is driven by kinetic energy of the motor vehicle, the fuel through the high pressure fuel line 34 in the high-pressure accumulator 8th be promoted, so that the valve 38 opened and the valves 36 and 37 are closed. In a further operating state, in which the actual pressure in the high-pressure rail 16 is less than the target pressure, is the valve 38 and 37 opened and from the high pressure pump 6 Fuel is in the high-pressure accumulator 8th Promoted and excess fuel under high pressure is through the high pressure fuel line 35 the high-pressure rail 16 fed. In another operating state, in which the actual pressure in the high-pressure rail 16 is greater than the pressure in the high-pressure accumulator 8th is from the high pressure pump 6 with several pump units, each with a working piston 27 each with a work space 28 include, from a portion of the pump units fuel the high-pressure accumulator 8th supplied and from another part of the pump units fuel the high-pressure rail 16 fed. This can be done by the high pressure pump 6 the fuel is increased in its pressure level to different pressure levels. In an exclusive operation of the motor vehicle with hydraulic energy is the internal combustion engine 18 shut off and the valve 38 open, allowing the fuel under high pressure of 4000 bar from the high-pressure accumulator 8th through the high pressure motor 4 flows to the fuel tank 10 and thereby from the high pressure motor 4 the motor vehicle by means of the drive wheels 25 is driven. In another operating state, in which the actual pressure and the target pressure in the high-pressure rail 16 smaller than in the high-pressure accumulator 8th , fuel is from the high-pressure accumulator 8th by means of the opened valve 37 the high-pressure rail 16 fed and simultaneously through the open valve 38 Fuel the high-pressure engine 4 supplied, so that thereby the motor vehicle with hydraulic energy from the high-pressure accumulator 8th is driven. In a further operating state, in which the actual pressure in the high-pressure rail 16 is greater than in the high-pressure accumulator 8th is from a part of the pump units of the high-pressure pump 6 Fuel through the high pressure fuel line 33 with an open valve 36 the high-pressure rail 16 fed and another part of the pumping units of the hydraulic machine 3 . 5 works as a high pressure motor 4 in which the fuel from the high-pressure accumulator 8th through the high pressure motor 4 the fuel tank 10 is forwarded.

In 2 and 3 is a cross section of the high pressure pump 6 , the high pressure motor 4 and the injector high pressure pump 15 for a high-pressure injection system 19 shown. The high pressure pump 6 has a drive shaft 12 with two cams 29 on that around an axis of rotation 41 performs a rotational movement. The rotation axis 41 lies in the drawing plane of 2 and is perpendicular to the plane of 3 , The working piston 27 as a working organ 26 is in a cylinder 49 as a piston guide 44 stored by a housing 43 is formed. A workroom 28 is from the cylinder 49 , the housing 43 and the working piston 27 limited. In the workroom 28 a channel opens as a fuel line 40 as fuel supply line 13 and fuel return line 14 with a low pressure valve 53 and a channel as a high-pressure fuel line 33 . 34 with a high pressure valve 50 , Through the channel or the fuel line 13 . 14 . 40 the fuel flows into the workspace 28 one when operating as a high pressure pump 6 and fuel from the workroom 28 out when operating as a high pressure engine 4 and through the channel or high pressure fuel line 33 . 34 the fuel flows under high pressure from the working space 28 again off when operating as a high pressure pump 6 and vice versa when operating as a high pressure motor 4 , The volume of the work space 28 is due to an oscillating stroke movement of the working piston 27 changed. The working piston 27 rests indirectly on the drive shaft 12 from. At the end of the working piston 27 is a roller shoe 45 with a roller 46 attached. The roller 46 can perform a rotational movement, the axis of rotation 57 in the drawing plane according to 2 lies and perpendicular to the plane of 3 stands. The roller 46 is with a sliding bearing 56 ( 3 ) on the roller shoe 45 stored. The drive shaft 12 with the at least one cam 28 has a wave rolling surface 42 and the roller 46 a roller rolling surface 48 on.

The roller tread 48 the roller 46 rolls on the wave rolling surface 42 the drive shaft 12 with the two cams 29 off, leaving between the caster 46 and the drive shaft 12 a contact surface 47 is available. The roller shoe 45 is in one of the housing 43 formed roller shoe storage stored as sliding bearing. A feather 58 or spiral spring 58 as an elastic element 59 between the case 43 and the roller shoe 45 is clamped, brings on the roller shoe 45 a compressive force on, leaving the roller rolling surface 48 the roller 46 in constant contact with the shaft rolling surface 42 the drive shaft 12 stands. The roller shoe 45 and the working piston 27 thus jointly carry out an oscillating lifting movement. The hydraulic machine as a high pressure motor 4 , as a high-pressure pump 6 and as injector high pressure pump 15 has several working organs 26 as a working piston 27 on which at the drive shaft 12 indirectly are stored and in 2 is only a working piston 27 shown.

The high pressure valve 50 includes a HD actuator 51 as an electromagnet 52 and a movable valve piston 55 , Analogously, the low-pressure valve comprises 53 an ND actuator 54 as an electromagnet 52 and a movable valve piston 55 , Instead of an electric actuator 51 . 54 For example, a hydraulically actuated actuator 51 . 54 (not shown) are used. The control unit 30 can by means of a current supply to the electromagnet 52 active opening and closing of the high pressure valve 50 and the low pressure valve 53 Taxes. A rotation angle sensor 60 detects the rotational angular position φ of the drive shaft 9 and as a function of the rotational angle position φ and the operating mode as a high-pressure pump 6 or as a high pressure motor 4 as well as the desired by the hydraulic machine to conductive volume flow of hydraulic fluid, ie fuel at the same speed of the drive shaft 12 the opening and closing of the high pressure valve takes place 50 and the low pressure valve 53 , This allows the oscillating working piston 27 in the operating mode of the high-pressure engine 4 can be used to convert hydraulic energy into mechanical energy by placing it on the working piston 27 also acting pressure force of the hydraulic fluid on the drive shaft 12 is transferred and vice versa in the operating mode of the high-pressure pump 6 mechanical energy from the drive shaft 12 on the working piston 27 is transferred, so that this against the hydraulic fluid to the working piston 27 acting compressive force is moved from a bottom dead center UT to a top dead center OT and thereby the pressure of the hydraulic fluid in the high-pressure accumulator 8th is increased because hydraulic fluid in the high-pressure accumulator 8th from the working piston 7 is promoted into it.

In 4 Fig. 10 is a graph of the pressure p of the hydraulic fluid in the working space 28 in the operating state of the hydraulic machine as a high-pressure pump 6 plotted on the ordinate and on the abscissa is the rotational angle position φ of the drive shaft 12 applied. During the entire movement of the working piston 27 from top dead center OT to bottom dead center UT is the high-pressure valve 50 constantly closed. The low pressure valve 53 is at top dead center and during an initial phase AP of the movement of the working piston 27 closed from top dead center to bottom dead center. Thus, during the initial phase AP, the movement of the working piston 27 from top dead center to bottom dead center, both the high pressure valve 50 as well as the low pressure valve 53 closed. As a result, the pressure p decreases due to the reduction of the volume of the working space 28 during the movement of the working piston 27 from the top dead center to the bottom dead center during the initial phase AP of the movement of the working piston 27 from the top dead center OT to the bottom dead center UT quickly. After the end of this initial phase AP, the low-pressure valve becomes ONV at the rotational angle position ONV 53 opened, so that due to the low pressure in the working space 28 the hydraulic fluid as fuel in the working space 28 can flow or from the pre-supply pump 11 is promoted. Due to the closing or the closed holding of the low pressure valve 53 during the initial phase AP, at the end of the initial phase AP, ie at the rotational angle position ONV, only very little force is available to open the low-pressure valve 53 needed because a small pressure difference between the pressure on the fuel line 13 . 40 and the pressure within the workspace 28 occurs because the pressure during the initial AP phase is strong inside the workspace 28 drops. During the further movement of the working piston 27 from the rotational angle position ONV to the bottom dead center UT, the filling of the working space takes place 28 with hydraulic fluid. At bottom dead center UT also takes place closing the low pressure valve 53 in that the rotational angle position of the bottom dead center UT is identical to the rotational angle position SNV of the closing of the low-pressure valve 53 , During the further movement of the working piston 27 from the bottom dead center UT to the top dead center OT, the opening of the high-pressure valve 50 only after the end of the initial phase AP at the rotational angle position OHV of opening the high-pressure valve 50 , During the initial phase AP of the movement of the working piston 27 from the bottom dead center UT to the top dead center OT are both the high pressure valve 50 as well as the low pressure valve 53 closed at the same time, so that during the initial phase AP of the movement of the working piston 27 from the bottom dead center UT to the top dead center OT a rapid increase in pressure within the working space 28 is performed. Due to this rapid pressure increase during the initial phase AP is at the rotational angle position OHV of the opening of the high pressure valve 50 a small force to open the valve piston 55 needed, as between the work space 28 and the high pressure fuel line 33 . 34 a slight pressure difference exists. To with the high pressure pump 6 also a lower volume flow of hydraulic fluid at a same speed of the drive shaft 12 To be able to perform, the closing of the high pressure valve takes place 50 not at top dead center as shown in FIG 4 in which the rotational angle position SHV of the closing of the high-pressure valve 50 the top dead center OT corresponds, but the closing of the high pressure valve 50 takes place before the top dead center during the movement of the working piston 27 from bottom dead center to top dead center and at the same time the low pressure valve 53 opened so that a part of the hydraulic fluid within the working space 28 during the movement of the working piston 27 from bottom dead center to top dead center during a not in 4 End phase not shown in the high pressure fuel line 33 . 34 is promoted, but in the fuel line 40 ,

In 5 is the pressure p of the hydraulic fluid within the working space 28 for the operating mode of the high-pressure engine 4 represented as a function of the angle of rotation φ. At top dead center OT of the working piston 27 the opening of the high pressure valve 50 in that the top dead center OT is the rotational angle position OHV of the opening of the high-pressure valve 50 equivalent. During the opened high pressure valve 50 fuel flows out of the high-pressure accumulator 8th through the high pressure fuel line 34 in the workroom 28 one, so that due to the big on the working piston 27 acting pressure of the hydraulic fluid is moved from top dead center to bottom dead center and this on the working piston 27 transmitted by the hydraulic fluid pressure force on the drive shaft 12 is transferred to the conversion of hydraulic energy into mechanical energy. Shortly before bottom dead center UT during the movement of the working piston 27 from top dead center OT to bottom dead center UT, the closing end of the high-pressure valve takes place at the beginning of an end phase EP at the rotational angle position SHV 50 and during this final phase EP is simultaneously the low pressure valve 53 closed. Due to the two closed high pressure and low pressure valves 50 . 53 thus decreases during this final phase of the movement of the working piston 27 from top dead center OT to bottom dead center UT the pressure within the working space 28 strong, so that at the end of the final phase EP and at bottom dead center UT a small pressure difference between the working space 28 and the pressure of the hydraulic fluid in the fuel line 40 is available. This is to open the low pressure valve 53 at bottom dead center UT only a small on the valve piston 55 applied force required to the low pressure valve 53 to open at bottom dead center. During the movement of the working piston 27 from bottom dead center to top dead center is initially the low-pressure valve 53 open, thereby allowing the hydraulic fluid from the working space 28 in the fuel line 40 is promoted into it. During the entire movement of the working piston 27 from bottom dead center to top dead center is the high pressure valve 50 closed. Shortly before the top dead center follows the beginning of a final phase EP at the rotational angle position SNV, the closing of the low-pressure valve 53 , so that during the final phase EP during the movement of the working piston 27 from the bottom dead center UT to the top dead center OT both the high pressure valve 50 as well as the low pressure valve 53 are closed, and thereby during the final phase EP a strong pressure increase due to the reduction of the volume of the working space 28 entry. Due to this pressure increase during the final phase EP during the movement of the working piston 27 from the bottom dead center to the top dead center occurs at top dead center, a small pressure difference between the working space 28 and the pressure of the hydraulic fluid in the high-pressure fuel line 33 . 34 on. This will move, ie the opening of the high pressure valve 50 at top dead center, since the rotational angle position OHV for opening the high-pressure valve 50 corresponds to the top dead center, for moving the valve piston 55 of the high pressure valve 50 a small force needed.

In 6 is another course of the pressure of the hydraulic fluid within the working space 28 for the high-pressure engine 4 shown. In deviation from the in 5 illustrated embodiment, wherein in 5 at a corresponding constant speed of the drive shaft 12 a maximum volume flow of hydraulic fluid through the high pressure motor 4 is directed in 6 a lower than the maximum possible volume flow of hydraulic fluid through the high pressure motor 4 at the same constant speed of the drive shaft 12 directed to the conversion of hydraulic to mechanical energy. Now the opening of the low pressure valve takes place 50 not at the bottom dead center, but during the movement of the working piston 27 from top dead center to bottom dead center before bottom dead center at the rotational angle position ONV of opening the low-pressure valve 53 , Before the rotational angle position ONV of opening the low-pressure valve 53 takes place at the rotational angle position SHV of the closing of the high-pressure valve 50 the closing of the high pressure valve 50 , Between the rotational angle position SHV and ONV, the final phase EP occurs. During the final phase EP is thus both the high pressure valve 50 as well as the low pressure valve 53 during the movement of the working piston 27 closed from the top dead center to the bottom dead center, so that during this final phase EP a very rapid pressure reduction within the working space 28 takes place, so that at the end of the final phase EP a small pressure difference between the pressure of the hydraulic fluid within the working space 28 and the pressure of the hydraulic fluid in the fuel line 40 occurs. As a result, at the end of the final phase EP at the rotational angle position ONV, a small force for opening the valve piston 55 of the low pressure valve 53 needed. During the movement of the working piston 27 From the rotational angle position ONV to the bottom dead center substantially no hydraulic energy is thus converted into mechanical energy, because within the working space 28 a very low pressure is present. In addition, the introduction of hydraulic fluid takes place in the working space 28 during the movement of the working piston 27 from the top dead center to the bottom dead center only from the rotational angle position OHV or the top dead center to the rotational angle position SHV of the closing of the high-pressure valve 50 so that thereby during a stroke of the working piston 27 a smaller volume of hydraulic fluid in the working space 28 is initiated as shown in FIG 5 ,

Overall, considered with the hydraulic hybrid system according to the invention 1 and the internal combustion engine system according to the invention 2 significant benefits. As hydraulic fluid of the hydraulic hybrid system 1 becomes the fuel of the internal combustion engine 18 , diesel used. In addition, the fuel in the high-pressure accumulator 8th held under a large pressure in the range between 3000 bar to 4000 bar, thereby characterized by the high-pressure accumulator 8th a large amount of energy per volume and per unit mass can be stored. An additional low pressure accumulator 9 is not necessary, as this of the already existing fuel tank 10 is formed. The high pressure pump 6 , the high-pressure engine 4 as well as the injector high pressure pump 15 form a structural unit, so that no additional units separated respectively for the high-pressure motor 4 , the high pressure pump 6 and the injector high pressure pump 15 required are. The control of opening and closing the high pressure valve 50 and the low pressure valve 53 The hydraulic machine is made with a control unit 30 active with HD and ND actuators 51 . 54 as a function of the rotational angle position φ, the operating state as a pump 5 or engine 4 and the desired and guided by the hydraulic machine volume flow of hydraulic fluid or fuel at a certain speed of the drive shaft 12 , making the hydraulic machine as a hydraulic pump 5 and as a hydraulic engine 4 can work with different volume flows at constant speed of the drive shaft 12 on hydraulic fluid. The HD actuator 51 and the ND actuator 54 requires little force to move the valve piston 55 due to the advantageous control of the high pressure and low pressure valves 50 . 53 , because when opening or closing only a small pressure difference between the working space 28 and the fuel line 40 or the high-pressure fuel line 33 . 34 is available.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• WO 2010/069857 A1 [0004]
• DE 102013204025 [0005]

Claims (15)

Hydraulic hybrid system ( 1 ) for a motor vehicle having an internal combustion engine ( 18 ), comprising - a high-pressure hydraulic motor ( 3 . 4 ) as a hydraulic machine ( 3 . 4 ) for the conversion of hydraulic energy into mechanical energy, - a high-pressure hydraulic pump ( 5 . 6 ) as a hydraulic machine ( 5 . 6 ) for the conversion of mechanical energy into hydraulic energy by a hydraulic fluid can be conveyed by the hydraulic pump, - a pressure accumulator ( 7 . 8th . 9 ) for storing hydraulic energy, - wherein the high-pressure pump ( 5 . 6 ) and the high pressure motor ( 3 . 4 ) of an identical hydraulic machine ( 3 . 4 . 5 . 6 ) and the hydraulic machine ( 3 . 4 . 5 . 6 ) at least one movable working organ ( 26 ) and at least one volume-variable work space ( 28 ), characterized in that the hydraulic machine ( 3 . 4 . 5 . 6 ) per working space ( 28 ) a low pressure valve ( 53 ) with an ND actuator ( 54 ) for opening and closing the low-pressure valve ( 53 ) and a high pressure valve ( 50 ) with an HD actuator ( 51 ) for opening and closing the high-pressure valve ( 50 ) for introducing and removing the hydraulic fluid into and out of the working space ( 28 ). Hydraulic hybrid system according to claim 1, characterized in that the hydraulic hybrid system ( 1 ), in particular the hydraulic machine ( 3 . 4 . 5 . 6 ), a control unit ( 30 ) and by the control unit ( 30 ) the opening and closing of the at least one low-pressure valve ( 53 ) and the at least one high-pressure valve ( 50 ) is controllable. Hydraulic hybrid system according to claim 1 or 2, characterized in that the movable at least one working member ( 26 ), in particular a working piston ( 27 ), indirectly on a rotating drive shaft ( 12 ) and on the at least one working organ ( 26 ) of one elastic element each ( 59 ), in particular a spring ( 58 ), a force, in particular compressive force, is applied directly or indirectly, so that a rotational movement of the drive shaft ( 12 ) an oscillating movement of the at least one working organ ( 26 ) conditionally and / or the at least one working organ ( 26 ) between a top dead center with a minimum volume of the associated working space ( 28 ) and a bottom dead center with a maximum volume of the associated working space ( 28 ) is movable and / or the at least one low-pressure valve ( 53 ) one each from the ND actuator ( 54 ) movable valve piston ( 55 ) and the at least one high-pressure valve ( 50 ) one each from the HD actuator ( 51 ) movable valve piston ( 55 ) and / or the at least one LP actuator ( 54 ) of an electromagnet ( 52 ) is formed and the at least one HD actuator ( 51 ) of an electromagnet ( 52 ) is formed. Hydraulic hybrid system according to one or more of the preceding claims, characterized in that the hydraulic machine ( 3 . 4 . 5 . 6 ) a rotation angle sensor ( 60 ) for detecting a rotational angular position of the drive shaft ( 12 ) and depending on the rotational angular position of the drive shaft ( 12 ) the opening and closing of the at least one low-pressure valve ( 53 ) and the at least one high-pressure valve ( 50 ) is controllable. Hydraulic hybrid system according to one or more of the preceding claims, characterized in that the at least one high-pressure valve ( 50 ) and the at least one low pressure valve ( 53 ) of the hydraulic machine ( 5 . 6 ) as a high-pressure pump ( 6 ) are controlled such that during a movement of the at least one working organ ( 26 ) from the bottom dead center to the top dead center, the at least one high-pressure valve ( 50 ) is open and the at least one low-pressure valve ( 53 ) is closed and during a movement of the at least one working organ ( 26 ) from the top dead center to the bottom dead center, the at least one high-pressure valve ( 50 ) is closed and the at least one low-pressure valve ( 53 ) is open and / or the at least high pressure valve ( 50 ) and the at least one low pressure valve ( 53 ) of the hydraulic machine ( 3 . 4 ) as a high pressure motor ( 3 . 4 ) are controlled such that during a movement of the at least one working organ ( 26 ) from the bottom dead center to the top dead center, the at least one high-pressure valve ( 50 ) is closed and the at least one low-pressure valve ( 53 ) is open and during a movement of the at least one working organ ( 26 ) from the top dead center to the bottom dead center, the at least one high-pressure valve ( 50 ) is open and the at least one low-pressure valve ( 53 ) closed is. Hydraulic hybrid system according to one or more of the preceding claims, characterized in that hydraulic fluid for storing hydraulic energy is fuel, in particular diesel, of the internal combustion engine ( 18 ) is inserted, in particular exclusively fuel is used as hydraulic fluid and / or in the case of an opened high-pressure valve ( 50 ) the working space ( 28 ) in fluid communication with at least one injector ( 17 ) and / or a high-pressure accumulator ( 8th ) and / or at an open low-pressure valve ( 53 ) the working space ( 28 ) in fluid communication with a low pressure accumulator ( 9 ), in particular a fuel tank ( 10 ), stands. Internal combustion engine system ( 2 ) for a motor vehicle, comprising - a high-pressure injection system ( 19 ) with an injector high pressure pump ( 15 ), preferably a high pressure rail ( 16 ), preferably a prefeed pump ( 11 ) for conveying a fuel from a fuel tank ( 10 ) to the injector high pressure pump ( 15 ), Preferably a drive train ( 20 ) for driving drive wheels ( 25 ) of the motor vehicle with an internal combustion engine ( 18 ) and / or a hydraulic motor ( 3 . 4 ), - a hydraulic hybrid system ( 1 ) with a high-pressure hydraulic motor ( 3 . 4 ) for the conversion of hydraulic energy into mechanical energy, a high-pressure hydraulic pump ( 5 . 6 ) for converting mechanical energy into hydraulic energy, a pressure accumulator ( 7 . 8th . 9 ) for storing hydraulic energy, characterized in that the hydraulic hybrid system ( 1 ) according to one or more of the preceding claims and / or the injector high-pressure pump ( 15 ) from the high pressure pump ( 5 . 6 ) is formed. Method for operating a hydraulic hybrid system ( 1 ), in particular a hydraulic hybrid system ( 1 ) according to one or more of claims 1 to 6, and / or an internal combustion engine system ( 2 ), in particular an internal combustion engine system ( 2 ) according to claim 7, comprising the steps of: - conveying hydraulic fluid from a low pressure accumulator ( 9 ) to a high-pressure accumulator ( 8th ) with a hydraulic pump ( 5 . 6 ), so that from the hydraulic pump ( 5 . 6 ) converts mechanical energy into hydraulic energy, - directs the hydraulic fluid from the high pressure accumulator ( 8th ) to the low pressure accumulator ( 9 ) and by a hydraulic motor ( 3 . 4 ), so that in the hydraulic motor ( 3 . 4 ) hydraulic energy is converted into mechanical energy and the mechanical energy is used to drive the motor vehicle, characterized in that the hydraulic pump ( 5 ) as a high-pressure pump ( 6 ) and the hydraulic motor ( 3 ) as a high pressure motor ( 4 ) of an identical hydraulic machine ( 3 . 4 . 5 . 6 ) and on the identical hydraulic machine ( 3 . 4 . 5 . 6 ) at least one working organ ( 26 ) is moved, so that the volume of the at least one working organ ( 26 ) associated working space ( 28 ) is changed. Method according to claim 8, characterized in that the hydraulic machine ( 3 . 4 . 5 . 6 ) per working space ( 28 ) a low pressure valve ( 53 ) with an ND actuator ( 54 ) for opening and closing the low-pressure valve ( 53 ) and a high pressure valve ( 50 ) with an HD actuator ( 51 ) for opening and closing the high-pressure valve ( 50 ) for introducing and removing the hydraulic fluid into and out of the working space ( 28 ) and / or as a hydraulic fluid, in particular exclusively, fuel, preferably diesel, of the internal combustion engine ( 18 ), in particular the fuel from the hydraulic machine ( 5 . 6 ) as a high-pressure pump ( 5 . 6 ) to the high-pressure accumulator ( 8th ) and / or from the hydraulic machine ( 5 . 6 . 15 ) as injector high pressure pump ( 15 ) to at least one injector ( 17 ) of the internal combustion engine ( 18 ) and / or the at least one high-pressure valve ( 50 ) of the hydraulic machine ( 3 . 4 . 5 . 6 ) by a high-pressure fuel line ( 33 . 34 ) in fluid communication with at least one injector ( 17 ) of the internal combustion engine ( 18 ) and / or to a high-pressure accumulator ( 8th ) and / or the at least one low-pressure valve ( 53 ) with a fuel line ( 13 . 14 . 40 ) in fluid communication with a fuel tank ( 10 ) and / or the at least one working organ ( 26 ), in particular a working piston ( 27 ), between a top dead center and a bottom dead center, in particular with a drive shaft ( 12 ) is moved. Method according to claim 9 or 10, characterized in that during operation of the hydraulic machine ( 5 . 6 ) as a high-pressure pump ( 5 . 6 ) during a movement of the at least one working organ ( 26 ) from the bottom dead center to the top dead center, the at least one high-pressure valve ( 50 ) is open and the at least one low-pressure valve ( 53 ) is closed and by a drive shaft ( 12 ) a force on the at least one working organ ( 26 ) is transmitted to move the working organ ( 26 ) from the bottom dead center to the top dead center opposite to that of the hydraulic fluid to the working member ( 26 ) applied compressive force, so that mechanical energy in hydraulic energy is converted and the hydraulic fluid from the at least one working space ( 28 ) and during a movement of the at least one working organ ( 26 ) from the top dead center to the bottom dead center, the at least one high-pressure valve ( 50 ) is closed and the at least one low-pressure valve ( 53 ) is opened, so that the hydraulic fluid in the working space ( 28 ) is conveyed into it. Method according to one or more of claims 8 to 10, characterized in that during operation of the hydraulic machine ( 3 . 4 ) as a high pressure motor ( 3 . 4 ) during a movement of the at least one working organ ( 26 ) from the top dead center to the bottom dead center, the at least one high-pressure valve ( 50 ) is open and the at least one low-pressure valve ( 53 ) is closed and the of the hydraulic fluid to the working organ ( 26 ) applied compressive force on a drive shaft ( 12 ) is transferred, so that hydraulic energy is converted into mechanical energy and the hydraulic fluid in the at least one working space ( 28 ) and during a movement of the at least one working organ ( 26 ) from the bottom dead center to the top dead center, the at least one high-pressure valve ( 50 ) is closed and the at least one low-pressure valve ( 53 ) is opened, so that the hydraulic fluid from the working space ( 28 ) is promoted out. Method according to claim 11, characterized in that during operation of the hydraulic machine ( 3 . 4 ) as a high pressure motor ( 3 . 4 ) during a movement of the at least one working organ ( 26 ) from the top dead center to the bottom dead center, the at least one high-pressure valve ( 50 ) is open and the at least one low-pressure valve ( 53 ) is closed and during the movement of the at least one working organ ( 26 ) from the top dead center to the bottom dead center, the high pressure valve ( 50 ) is closed, so that the inflow of the hydraulic fluid into the working space ( 28 ) is interrupted and the sooner the high pressure valve ( 50 ), the less hydraulic energy is converted into mechanical energy and vice versa. Method according to claim 12, characterized in that during operation of the hydraulic machine ( 3 . 4 ) as a high pressure motor ( 3 . 4 ) during the movement of the at least one working organ ( 26 ) from top dead center to bottom dead center after closing or closing, or just before closing the high pressure valve (FIG. 50 ) the low pressure valve ( 53 ) is opened to a strong pressure reduction in the working space ( 28 ) to avoid. Method according to one or more of claims 11 to 13, characterized in that during operation of the hydraulic machine ( 3 . 4 ) as a high pressure motor ( 3 . 4 ) during a movement of the at least one working organ ( 26 ) from the bottom dead center to the top dead center, the at least one high-pressure valve ( 50 ) and that at least one low pressure valve ( 53 ) is initially opened and closed before top dead center, so that during the movement of the at least one working organ ( 26 ) from the bottom dead center to the top dead center, the pressure in the working space ( 28 ) due to the closed high pressure and low pressure valve ( 50 . 53 ) and at the top dead center a smaller pressure difference between working space ( 28 ) and a high pressure line ( 33 . 34 ), in particular high-pressure fuel line ( 33 . 34 ) on the high pressure valve ( 50 ) is present as without closing the at least one low-pressure valve ( 53 ) before top dead center and the HD actuator ( 51 ) thereby requires a smaller force to open the valve piston ( 55 ) of the high pressure valve ( 50 ) due to the smaller pressure difference. Method according to one or more of claims 10 to 14, characterized in that during operation of the hydraulic machine ( 5 . 6 ) as a high-pressure pump ( 5 . 6 ) during a movement of the at least one working organ ( 26 ) from the bottom dead center to the top dead center, the at least one high-pressure and low-pressure valve ( 50 . 53 ) in an initial phase of the movement of the working organ ( 26 ) are closed, so that the pressure in the working space ( 28 ) and thereby a smaller pressure difference between the working space ( 28 ) and a high pressure line ( 33 . 34 ), in particular high-pressure fuel line ( 33 . 34 ), on the high pressure valve ( 50 ) than without initially closing the high pressure valve ( 50 ) and only after the initial phase of the movement of the at least one working organ ( 26 ) only the high pressure valve ( 50 ) and thereby the HD actuator ( 51 ) requires a small force to open the valve piston ( 55 ) of the high pressure valve ( 50 ) due to the smaller pressure difference.

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