WO2015091188A1

WO2015091188A1 - Hydrostatic piston engine

Info

Publication number: WO2015091188A1
Application number: PCT/EP2014/077329
Authority: WO
Inventors: Gottfried Hendrix
Original assignee: Robert Bosch Gmbh
Priority date: 2013-12-18
Filing date: 2014-12-11
Publication date: 2015-06-25
Also published as: DE102014225527A1

Abstract

A hydrostatic radial piston pump is disclosed, the swept volume/piston units of which are hydraulically connected to one another in pairs and are divided here between a first rotor section and a second rotor section. In one specific embodiment, the pistons of all of the pairs of swept volume/piston units are guided with cams along a common cam curve. During operation as a motor, the absorption capacity of the engine can be adjusted via an angular offset between the two rotor sections during revolving of the two rotor sections since the one unit of each pair conveys part of the absorption capacity of the other unit into the latter. During operation as a pump, the delivery volume of the engine can be adjusted via the angular offset since the one unit of each pair receives part of the delivery volume of the other unit.

Description

Hydrostatic piston machine

description

The invention relates to a hydrostatic piston engine, in particular a hydrostatic radial piston pump according to the preamble of patent entitlement l.

The publication DE 10 2004 049 864 A1 discloses a hydrostatic axial piston machine and a hydrostatic radial piston machine which have a stator and a rotor and the two groups of displacements, namely first displacements and second displacements. In the first displacements, first pistons and second pistons carry second piston strokes, the first and second pistons each being supported on a lifting element. In each case a first displacement and a second displacement are connected in pairs fluidly with each other. The lifting movements, which carry out the two pistons of two interconnected displacements, are in their phase against each other. By shifting the phases, the stroke volume of the hydrostatic machine can be infinitely varied. At 100% displacement, the first pistons and the second pistons of a Hubraumpaars move synchronously. The larger the phase shift is selected, the lower the stroke volume of the machine. This applies up to an angle a / 2, which corresponds to half the wavelength of a cam of the cam ring. For the phase shift, the first piston and the second piston are each assigned their own lifting elements, via which the pistons are guided and which can be rotated relative to one another. A disadvantage of the known piston engines that a main drive or a main output of the piston engine and continue a structurally different actuator for the relative rotation of the lifting rings are required against each other. Such an actuator is not disclosed in DE 10 2004 049 864 A1.

On the other hand, the invention is based on the object to provide a hydrostatic piston engine, in which only one type of drive is necessary for the drive or for the output and for adjusting the phase shift to use common parts and to reduce the design effort. Also, a high Verstelldynamik should be achievable.

This object is achieved by a hydrostatic piston engine having the features of patent claim 1.

The displacements of the hydrostatic piston engine according to claim 1 are divided into a group of first displacements and a group of second displacements, wherein in each case a first displacement and a second displacement in pairs are fluidly interconnected. There are first pistons, each of which is supported on a lifting element and execute lifting movements in the first displacements, and second pistons are present, which are also each supported on a lifting element and execute lifting movements in the second displacements. According to the characterizing part of patent claim 1, the rotor comprises a first part rotor whose rotation relative to the stator causes strokes of the first piston, and a second part rotor whose rotation relative to the stator causes strokes of the second piston. The two sub-rotors are operable with an adjustable to adjust the stroke volume angle offset to each other at the same speed. An angular offset of zero is given when the two pistons of a pair of hubs carry out synchronous lifting movements. Then, at an angular offset, zero is the stroke volume the piston engine maximum. At an angular offset of 180 degrees, the pistons of a Hubraumpaares move in opposite directions, so that the stroke volume of the reciprocating engine is zero. If an angular misalignment exceeding 180 degrees is possible up to 360 degrees or beyond, the piston machine can be used in 4-quadrant operation. In the case of a motor so the displacement and in the case of a pump, the delivery volume can be adjusted. If the piston engine is to be operated as a pump, and if the two groups of displacements and pistons have the same volume per stroke, for example, to operate the piston engine as a pump two basically identical drive machines are necessary, each of which must apply half the power of the pump and with which at the same time the stroke volume can be adjusted. A separate adjusting device for the stroke volume is not necessary. The two rotors can in principle be designed identically. Thus, identical parts can be provided and the design effort is reduced. If the stroke volume of the hydrostatic piston engine according to the invention is to be constant, the two partial rotors revolve at identical speeds. The particular advantage of a hydrostatic piston machine according to the invention is that for an adjustment of the stroke volume, the two partial rotors only have to run at different speeds for a short time and after this phase of running at different rotational speeds both again with mutually identical and optionally the same rotational speeds as before the adjustment rotate. In a hydrostatic piston machine according to the invention, one is a partial rotor with a first drive machine and / or driven machine and the other partial rotor with a second drive machine and / or

Output machine coupled. The two machines allow a circulation of the two part rotors at the same speed and can cause a phase offset by a short-term different speed of the two sub-rotors between them. For example, both partial rotors with be coupled to an electric motor. It is possible that these electric motors can also work as generators.

The phase offset between the two sub-rotors is referred to below as the angular offset.

In principle, all displacements with the pistons can be arranged both in the rotor and in the stator. Accordingly, when the pistons are arranged in the rotor, the lifting element is the stator or a part of the stator, and when the pistons are arranged in the stator, the lifting element is correspondingly the rotor or a part of the rotor. If the displacements and the pistons are arranged on the rotor, then the first pistons and the second pistons can be supported on a one-piece or constructed of a plurality of immovably held together parts lifting element. On the other hand, if the displacements and the pistons are arranged on the stator, each of the two sub-rotors has a lifting element.

Thus, according to a first concept of the piston engine according to the invention, the stator as a lifting element on a common cam ring or two - preferably substantially identical - Hubringe on which or on which distributed over the circumference at equal angular intervals in the radial or axial direction cams are formed along which the pistons of both groups are guided. At the one rotor part, the first displacement chambers are formed in the radial or axial direction, while the second displacement chambers are formed on the other partial rotor in the radial or axial direction.

A hydrostatic piston machine according to the invention can be designed as a radial piston machine or as an axial piston machine. The lifting elements can be located inside the pistons - in a radial piston machine radially inside the pistons, in an axial piston machine between the pistons first piston and the second piston - or outside the piston - in a radial piston engine radially inside the piston, in a Axialkol- benmaschine between the first piston and the second piston - are. The lifting elements are located on the stator, they may be integrally formed with each other and are distinguishable from each other only by the track of the pistons.

Advantageous embodiments of a hydrostatic piston machine according to the invention can be found in the dependent claims.

In principle, it is possible for each partial rotor and an associated stator to be designed as a separate hydrostatic unit with a housing. There are then in principle two hydrounits present, each of which is driven by an electric motor and whose pressure connections are brought together. Preferably, however, the two partial rotors and the stator are housed in a common housing in which two drive shafts, one of which is coupled to the one rotor part and the other to the other rotor part, are rotatably mounted. Thus, the piston engine is a compact construction readily manageable unit.

Preferably, the lifting elements on a same plurality of uniformly distributed over the circumference cam. With one revolution of the rotor, the pistons thus make several strokes, so that the piston engine has a large maximum displacement. For an adjustment of the stroke volume from a maximum value to a value of zero, only an adjustment by half the angle over which a cam extends, necessary. This achieves a high adjustment dynamic.

For the creation of the pairs of displacements, it is particularly favorable if the pairs of interconnected displacements in operation with maximum times the stroke volume in pairs in the same axial plane in the direction of the axis of rotation lying behind each other.

Preferably, one partial rotor is coupled to an electric machine controllable in its rotational speed. If only a pure pump operation of the reciprocating engine is provided, then the electric machine is an electric motor controllable in its rotational speed. During engine operation of the piston engine, the electric machine is an electric generator. If both motor and pump operation is provided, the electric machine can be operated both as a motor and as a generator. To adjust the stroke volume, the speed of the electric machine is briefly changed compared to the speed of the other partial rotor.

So that the coupled with their variable speed electric machine part rotor follows the other part rotor in speed and thus the desired adjustment is obtained quickly and accurately, the speed of the variable in their speed electric machine depending on the angular offset between the two part rotors, preferably can be determined by a rotation angle sensor arrangement, be adjustable via a control loop.

Preferably, one partial rotor is coupled to a first electric machine, whose rotational speed can be regulated as a function of the angular offset between the two partial rotors, and the other partial rotor is coupled to a second electric machine, which is preferably likewise variable in its rotational speed. Deviating from the other part rotor but can also be driven by a wind turbine, a water turbine, an extruder shaft or a laundry drum. If the first Elektronnasch ine is an asynchronous machine to which a rotatable flywheel is rotatably coupled, power peaks can be compensated by the flywheel. Preferably, the reciprocating engine is a radial piston pump having an outer common cam ring, both groups having an equal number of cylinder piston units which rotate in synchronous operation with an angular offset of 0 degrees. To minimize friction, the pistons are guided over respective rolling elements along the common lifting ring.

In a compact embodiment, an output shaft of the main electric motor is integrally formed with the first sub-rotor, while an output shaft of the compensating electric motor is formed integrally with the second sub-rotor.

In an embodiment which is suitable for 2-quadrant operation, the hydrostatic piston engine has a high-pressure connection and a low-pressure connection, which are not exchanged. In this case, the angular offset is possible up to a maximum angular offset, which corresponds to half the wavelength of a cam of the common cam ring or the two lifting rings. In one embodiment, which is suitable for 4-quadrant operation, the hydrostatic piston engine has a first working connection and a second working connection, both of which can be used as a high-pressure connection and as a low-pressure connection. The angular offset is possible up to a maximum angular offset, which corresponds to the wavelength of a cam of the common cam ring or the two lifting rings. In one embodiment, which is likewise suitable for 4-quadrant operation, the hydrostatic piston engine has a first working connection and a second working connection, both of which can be used as a high-pressure connection and as a low-pressure connection. An angular offset is possible, which extends beyond the angular extension of a cam of the common lifting element or of the two separate lifting elements. Device-technically simple, it is when angle offset is not limited.

In a further development of the 4-quadrant machine, a slot control is provided between the two rotors, via which a pressure side change between the two working ports of the reciprocating engine can be brought about by adjusting an angular offset between the two rotors, which is greater than the angle, which corresponds to half a wavelength of a cam.

In a preferred development of the 4-quadrant machine, a plurality of first openings connected to the first working connection and a plurality of second openings connected to the second working connection are formed in a section of the housing adjacent to the first part rotor. The second displacements located in the second part rotor are alternately connected to the first openings and to the second openings during the circulation of the part rotors via channels formed in the first part rotor. The channels extend from the openings of the housing section through the first part rotor to the second part rotor. The channels preferably have a pairwise spacing equal to half a wavelength of a cam, the number of channel pairs corresponding to the number of cams. The displacements of the first part rotor are thus connected in directly via the channels and the displacements of the second part rotor with the housing-side openings. In a preferred embodiment of the slot control, this has circular arc-shaped connecting grooves, which are formed in a first bearing region of the two partial rotors and between the channels and the displacements of the second partial rotor, and which are dimensioned such that at an angular offset greater than half the angular extent of a cam, the displacements of the second sub-rotor and thus the pairs of displacements are each connected to the pair-adjacent channel and thus with an adjacent opening. The word adjacent is to be understood as viewed in the circumferential direction. The pairs of lifting spaces are therefore connected to one of the second openings or vice versa instead of to one of the first openings when the pressure is changed.

In a preferred development of the 4-quadrant machine, the first displacements are each connected in pairs via one or two arcuate connecting grooves, which are formed in a second abutment region between the two sub-rotors, with the associated displacement of the second sub-rotor. In this case, the one or the two respective connecting grooves are so long that the two displacements remain in pressure medium connection up to the maximum angular offset.

In a particularly preferred concept of the piston engine according to the invention, the displacements in which the pistons move, formed in the radial or axial direction of the stator, wherein the first lifting element on the first part rotor and the second lifting element on the second part rotor. For each pair of Hubrapair a control valve arrangement is present, via which the Hubraumpaar can be connected to the two working ports. For one-way pump operation, the control valve assembly may be formed by two simple passive check valves, one of which is the pressure valve and the other is the suction valve. In itself, the lifting elements can be formed by an eccentric ring or a swash plate. However, preference is given to the lifting elements in the radial or axial direction many cams are formed so that the pistons make several strokes during a revolution. Preferably, the two lifting elements are substantially identical. Preferably, the control valve assembly comprises at least one movable control valve body, which is actuated in response to the angular position of a partial rotor. In this case, a pair of pairs of hubs is connected depending on the switching state of the control valve arrangement with the one working connection or with the other working connection. The Steuerven- tilanordnung can be operated mechanically or electromagnetically.

With such an actively actuated control valve arrangement, including a change in the direction of rotation of the rotor, a 4-quadrant operation is possible. This means that the hydrostatic piston machine can promote as a pump in one direction and after a change in direction in the other direction and that the hydrostatic piston engine as a motor when flowing in one direction in one direction of rotation and flow in the other direction in can drive the other direction of rotation.

If a changeover valve arrangement is present, depending on the switching state of which two connections of the control valve arrangements can be connected to the two working connections in a first manner or in a reversed manner, pumping into one and the other is also possible with a passive control valve arrangement without changing the direction of rotation of the partial rotors Direction possible. With an actively operable control valve arrangement, a 4-quadrant operation without change of direction is possible.

The control valve arrangements assigned in each case to the pairs of cylinder-piston units can preferably be controlled via a control rotor which rotates with the two partial rotors. Here is the control rotor so coupled to the two sub-rotors that he always has half the angular offset, so always assumes an intermediate position between the two sub-rotors. On the control rotor are according to a preferred embodiment

Control cam formed over which the control valve body are actuated. For this purpose, the control cam can be distributed uniformly on the outer circumference of the control rotor. Each control valve assembly may include an elongated control valve body or a plunger extending radially from the outer control valves to the inner control cams.

Alternatively, the slot control may be formed on the control rotor, which rotates with the two sub-rotors. Also in this embodiment, the control rotor is coupled to the two sub-rotors in such a way that it always has half the angular offset, ie always occupies an intermediate position between the two sub-rotors.

The control rotor can have or be a control disk which has two abutment ring surfaces which are arranged parallel to one another and perpendicular to the axis of rotation. The slot control may be formed by circular arc-shaped through-holes distributed on the circumference of the control disk and by openings arranged on the circumference of the stator. The passage recesses extend between the two Anlageringflächen. The openings are arranged on both sides of the abutment ring surfaces on the stator.

The always automatically adjusting half angular offset of the control rotor can be realized via a meshing engagement with the two part rotors. In this case, at least one toothed wheel can be used which is mounted with a radial axis of rotation on the control rotor, and whose teeth mesh with respective teeth of the two sub-rotors. The control rotor can be driven by an unregulated drive motor and the drive of the two sub-rotors via the control rotor, wherein the Hubvolumenverstellung by driving the sub-rotors via controlled electric motors.

A preferred development has a Nachsaugeinrichtung and a pressure relief for each cylinder-piston pairing. As a result, an impermissible overpressure and an unacceptable negative pressure in a Überde- ckungsphase the control slots are prevented in a suction or pressure-generating movement of the balance piston. The oil relief and Ölnachsaugung preferably take place in or out of the housing of the drive unit. A preferred development has a stop which is provided between the two rotors for limiting the angular offset. This can be formed by a pin on the main rotor and a circular arc-shaped slot or a circular arc-shaped groove on the second part rotor.

Several embodiments of a hydrostatic piston engine according to the invention are shown in the drawings. With reference to the figures of these drawings, the invention will now be explained in more detail.

Show it

Figure 1 shows a first embodiment in the form of an inventive

Radial piston pump in a longitudinal section without angular offset of the two partial rotors,

FIG. 2 shows the radial piston pump without angular offset in a section along the line AA from FIG. 1, FIG. 3 shows the radial piston pump without angular offset in a section along the line BB from FIG. 1,

4 shows the radial piston pump according to FIG. 1 with an angular offset between the partial rotors in a section corresponding to the section B-B from FIG. 1, FIG.

FIG. 5 shows the radial piston pump according to FIG. 1 with a maximum angular offset in a section corresponding to the section B-B from FIG. 1,

FIG. 6 shows the radial piston pump according to FIG. 1 with an angular offset in a longitudinal section,

FIG. 7 shows the radial piston pump according to FIG. 6 in a section along the line C-C,

FIG. 8 shows a second embodiment in a first longitudinal section

Form one

Radial piston pump according to the invention without angular offset and with

Nachsaugvorrichtung and pressure protection,

FIG. 9 shows the radial piston pump according to FIG. 8 without angular offset in one

Longitudinal section in a second sectional plane,

10 shows a detail of a development of the two rotors and of the housing of the radial piston pump according to FIG. 8 without angular offset, FIG.

FIGS. 1 1 shows the detail of the development according to FIG. 8 with an angular offset,

12 shows the detail of the development according to FIG. 8 with a maximum angular offset, FIG.

FIG. 13 shows a circuit diagram of the two exemplary embodiments of a radial piston pump according to the invention,

FIG. 14 shows a half longitudinal section through a third exemplary embodiment, in which the pistons are located in the stator and the lifting elements are rotatable relative to one another,

FIG. 15 shows a section along the line XX from FIG. 14, FIG. 16 shows a section along the line ZZ from FIG. 14,

17 shows a section along the line Y-Y of FIG. 14, FIG.

FIG. 18 shows the third exemplary embodiment as a pump with a positive maximum displacement in a suction stroke,

19 shows the third embodiment as a pump with a positive maximum displacement in a pressure stroke,

FIG. 20 shows the third exemplary embodiment as a pump with a displacement of zero,

FIG. 21 shows the third exemplary embodiment as a pump with a negative maximum stroke volume in one pressure,

FIG. 22 shows a circuit diagram of a fourth exemplary embodiment which can only be operated as a pump in one direction,

FIG. 23 is a circuit diagram of a fifth embodiment operable as a pump in two directions;

FIG. 24 shows a circuit diagram of a sixth exemplary embodiment which, taking into account a change in the direction of rotation in a

Quadrant operation is operable,

Figure 25 shows a half section through a seventh embodiment, which is designed as an axial piston machine, and

FIG. 26 shows the seventh exemplary embodiment in a development,

FIG. 27 shows a half longitudinal section of the sixth exemplary embodiment according to FIG. 24 in an embodiment with a control rotor,

FIG. 28 is a schematic diagram of the sixth embodiment without angular offset with maximum displacement,

FIG. 29 shows a schematic representation of the sixth exemplary embodiment with an angular offset,

FIG. 30 shows a schematic diagram of the sixth exemplary embodiment with angular offset and stroke volume equal to zero,

31 is a schematic diagram of the sixth embodiment with an angular offset,

FIG. 32 shows a detail of a longitudinal section of an eighth embodiment with a control rotor, FIG. 33 shows the control rotor of the eighth exemplary embodiment according to FIGS. 31 and 32,

34 is a schematic diagram of the eighth embodiment without angular offset with maximum displacement,

FIG. 35 shows a basic illustration of the eighth exemplary embodiment with an angular offset,

FIG. 36 shows a schematic diagram of the eighth exemplary embodiment with angular offset and stroke volume equal to zero,

FIG. 37 is a schematic diagram of the eighth embodiment with an angular offset,

FIG. 38 shows a detail of a longitudinal section of the fourth exemplary embodiment according to FIG. 22,

FIG. 39 shows a longitudinal section of a ninth embodiment with a control rotor,

FIG. 40 shows a section of a longitudinal section of a tenth embodiment with electromagnetically operated switching valves, and FIG. 41 shows a longitudinal section through a modification of the ninth embodiment. Figure 1 shows a first embodiment of the radial piston pump according to the invention in a longitudinal section. In a housing 1, a first part rotor 2 and a second part rotor 4 adjacent to each other about a rotation axis 6 are rotatably mounted. Here are distributed on the rotor part 2 evenly distributed over the circumference extending in the radial direction first displacement piston units 8 are provided. A first unit 8 has a first piston 3, which can perform 5 strokes in a cylindrical first displacement. In the same way 4 second displacement piston units 10 are provided on the sub rotor. Each unit 10 has a second piston 7, which can perform 9 strokes in a cylindrical, second displacement. Of both groups of units 8, 10, only one unit 8, 10 is shown in FIG. On the outer circumference of both partial rotors 2, 4 a common housing-fixed cam ring 12 is provided, on whose inner circumference a plurality, for example ten, evenly distributed cam 14 are formed, of which in the illustration of Figure 1, only one side edge of a cam 14 can be seen. The number of cams 14 is usually different from the number of displacement piston units 8 or 10, so that the rollers 1 1 occupy different positions with respect to the cams 14 and the pistons 3, 7 at different times in a particular time their strokes are. To the pistons 3 and 7 of each unit 8, 10, a roller 1 1 is rotatably mounted, via which the pistons 3, 7 are supported on the cam ring 12. The pistons 3, 7 thus follow in their strokes the course of the path formed by the cam 14 on the cam ring 12.

The housing 1 together with the cam ring 12 can be seen as a stator of the hydrostatic piston machine see.

During operation of the radial piston pump according to the invention, the partial rotor 2 is driven by a first electric motor 16, while the partial rotor 4 is driven by a second electric motor 18. In this case, an output shaft 20, designed as a hollow shaft, of the first electric motor 16 is formed integrally with the partial rotor 2, while an output shaft 22, likewise designed as a hollow shaft, of the second electric motor 18 is formed integrally with the partial rotor 4. The two electric motors 16, 18 are adjustable in their speed. On each partial rotor 2, 4 are permanent magnets 17 of the electric motors 16, 18, while windings 19 are arranged on the stator.

In each case a unit 8 and a unit 10 are fluidly connected to each other and form a pair. Each unit 8 is over a plurality of

housing-side openings 24a, 24b and via a respective channel 26 in the sub-rotor 2 alternately connected to a high-pressure port and a low-pressure connection (both not shown) of the radial piston pump becomes. Furthermore, via a compensation fluid path, the displacement 9 of a unit 10 is always fluidically connected to the displacement 5 of a unit 8. The compensation fluid path has a first compensation channel formed in the first part rotor 2 and a second compensation channel 28 formed in the second part rotor 4.

In the operating state shown in FIG. 1, the radial piston pump has no angular offset .beta. Between its two partial rotors 2 and 4. The units 8 and 10 run driven by the two electric motors 16 and 18 about the rotation axis 6 at the same speed, wherein each pair forming units 8, 10 are arranged in the same axial plane one behind the other and the two pistons 3, 7 of a pair of units 8, 10 synchronous lifting movements. With an angular offset ß = 0 degrees, the delivery volume of the radial piston pump is thus maximum.

In order to set an angular offset β> 0 degrees, the second electric motor 18 rotates slightly slower for a short time, in order then to continue rotating at the same rotational speed as the first electric motor 16. Then the unit 10 in each case swallows part of the delivery volume of the unit 8, so that the delivery volume of the radial piston pump is reduced.

To limit the angular offset between the two part rotors ß 2, 4, a stop 30 is provided between them, which is explained in more detail in relation to the figures 3 to 5.

FIG. 2 shows the radial piston pump according to FIG. 1 in the section A-A from FIG. 1. In this example, five units 8 of the sub-rotor 2 are shown, the piston 3 via respective rollers 1 1 along the cam 14 of the

Cam ring 12 are guided. The wavelength of a cam 14 corresponds to an angle a, which results from the quotient of 360 degrees and the number of cams 14. Adapted to the circular arc-shaped openings 24a, 24b, which are formed in the housing 1. In this case, high-pressure openings 24a and low-pressure openings 24b are arranged alternately and each extend approximately over the angle a / 2, which corresponds to half the wavelength of a cam 14.

FIG. 2 shows that the openings of the channels 26 of the units 8 are guided along the low-pressure openings 24b and the high-pressure openings 24a, so that the units 8 alternate with the high-pressure connection and the low-pressure connection, depending on their position relative to the cams 14 the radial piston pump are connected. The pressure ratios described apply under the assumption of a drive direction in Figure 2 counterclockwise according to the arrow.

FIG. 3 shows the radial piston pump according to FIG. 1 in the section BB from FIG. 1 without angular offset β between the partial rotor 2 and the partial rotor 4 shown in FIG. 3. Its units 10 each stand at the same rotational position as the assigned units 8 (see FIG. 2). The pairwise hydraulic interconnection of the units 8, 10 is realized in each case by a sealing contact between an opening of the compensation channel 28 of the partial rotor 4 at a respective arcuate connecting groove 32 of the partial rotor 2 (not shown in detail in Figure 3). In this case, the connecting grooves 32 each extend along an angle which corresponds to the maximum angular offset β _max between the two sub-rotors 2, 4. In the first exemplary embodiment according to FIGS. 1 to 7, the maximum angular offset β _max = a / 2. The changing radial distance of the connecting grooves 32 and the mouths of the compensation channels 28 of the rotation axis 6 is provided only for reasons of space.

The stop 30 consists of a circular arc-shaped groove 43 formed on the partial rotor 4, which extends in the partial rotor 4 along an angle a / 2, and of a pin 44 formed on the partial rotor 2, which engages in this groove. FIG. 4 shows the cross-section BB according to FIG. 3 with only one exemplary unit 10, wherein an angle offset β greater than zero has been set in order to realize a delivery volume of the radial piston pump which is smaller than the maximum delivery volume. As a result, the mouth of the compensation channel 28 and the groove of the stop 30 assume a correspondingly changed position relative to the partial rotor 2, of which only one connecting groove 32 and the journal of the stop 30 are shown in FIG. FIG. 5 shows a section BB, which substantially corresponds to the representation of FIG. The difference is that now a maximum angular offset β _{max has been} set, which corresponds to half the wavelength of a cam 14. With this angular offset β _max , the unit 10 shown by way of example always precisely compensates the stroke movement and thus the stroke volume of the associated unit 8 (not shown in FIG. 5). With this angular offset β _max , the delivery volume of the radial piston pump is thus equal to zero.

FIG. 6 shows the first exemplary embodiment of the radial piston pump according to the invention according to FIG. 1 in a longitudinal section with an angular offset .beta., Wherein 0 degrees <.beta. <90 degrees relative to the period length of a cam 14. As a result, the two pistons of the pairs of units 8, 10 are supported at different locations of a cam 14. FIG. 7 shows a section CC of the radial piston pump with the angular offset β shown in FIG. As a result, each pair of rollers 1 1 can be seen, one of which, shown by a solid line roller 1 1 of the respective unit 8 and the other, shown by the dashed line roller 1 1 (not shown in Figure 7) unit 10 of a pair assigned. FIG. 8 shows a second exemplary embodiment of the radial piston pump according to the invention in a first longitudinal section, wherein the angular offset β is equal to 0 degrees. The essential difference from the first embodiment according to the preceding figures is the fact that in the second embodiment, a 4-quadrant operation is possible. This means that, for example, with a given drive direction of the two partial rotors 102, 104 by the two electric motors 16, 18 a change of high pressure and low pressure at the two (not shown in Figure 8) working connections and a reversal of the conveying direction is possible. For this purpose, the partial rotor 102 has a plurality of channels 134 which are connected to the

housing-side openings 24 a, 24 b are passed, and connect the respective openings 24 a, 24 b with the units 10. The filling and emptying of the units 8 takes place via the sub-rotor 104, more precisely via the passage 134 of the sub-rotor 102 and a passage 135 of the divider 104 and via the equalizing fluid path with the equalization passage 28, via which the previously described uninterrupted connection of the two units 8, 10 of a pair is realized.

In the second embodiment, each unit 10 is associated with a Nachsaugventil in the form of a check valve 40 and a pressure relief valve 42. Thereby, each displacement piston unit 10 is protected from an inadmissible high pressure and an impermissibly low pressure in a Überdeckungsphase the control slots. In the process, the pressure-limiting valve 42 injects directly into the housing 1, while it is sucked in directly from the housing 1 via the check valve 40. Of course, also in the other embodiments, the units can be associated with intake valves and pressure relief valves.

FIG. 9 shows the radial piston pump according to FIG. 8 in a second longitudinal section, again without angular offset β. The cutting plane is pivoted about a rotation angle about the axis of rotation 6, which is the piston distance the radial piston pump corresponds. Thus, it can be seen that the compensation channel 28 of the shown pair of displacement piston units 8, 10 is located radially further inward than the compensation channel 28 of the pair shown in FIG. Furthermore, it can be seen that the two communicating channels 134, 135 are located radially further outward than the channels 134, 135 according to FIG. 8. In both cases, the radial offset has been realized only for installation space reasons.

FIG. 10 a shows a development A-A of the two rotors 102, 104 of the second exemplary embodiment with a radial distance from the axis of rotation 6, which corresponds to that of the outer compensation channel 28 according to FIG. An angle offset β of zero degrees is set. It can be seen that the displacements of the piston pairs PA, PB are in each case fluidically connected via the compensation channel 28 and via a contact region between the two rotors 102, 104.

FIG. 10b shows the radially inward development BB (compare FIG. 8). In this case, the circular arc-shaped openings 24a, 24b formed in the housing 1 are shown, wherein in the operating state illustrated in Figures 10, the openings 24a are connected to the high pressure working port B of the radial piston pump, while the intermediate openings 24b with the low pressure leading Arbeitsan - A connection are connected. In the partial rotor 102, the channels 134 are arranged obliquely to the axis of rotation 6 (see FIG. 8). The channels 134 open (when viewing the suction direction) in each case in an arcuate connecting groove 136 whose distribution corresponds to the circumference of those of the pistons PA and PB. Each channel 135 can communicate with two of the connecting grooves 136 as a function of the angular offset β. More specifically, at an angular displacement β to less than a / 2, communication with a first communication groove 136 is and at an angle offset β of more than a / 2, communication with the second adjacent connection groove 136 is given.

FIG. 11 shows an angular offset β of exactly a / 2 of the partial rotor 4 relative to the partial rotor 102. From the development AA according to FIG. 11a, it can be seen that the connecting grooves 132, 133 form the fluidic connection between the two units 8 and 10 of the respective unit Pair possible despite the angular offset ß. For this purpose, each serve the two circular arc-shaped connecting grooves 132, 133rd

In FIG. 11b it can be seen in the corresponding development BB that the pairs of units 8, 10 at the selected angular offset β of exactly a / 2 are shut off from the working connections, since the channels 135, via the two units 8, 10 is supplied or relieved of the respective pair, in each case abuts on the sub-rotor 102 between two connecting grooves 136, so that no pressure medium to the working ports A, B flow or can be sucked by the working ports A, B. The pairs of units 8, 10 push back and forth only. 12 show a maximum angular offset β _max = α of the partial rotor 104 relative to the partial rotor 102. In the development AA of FIG. 12 a, it is shown that the connecting grooves 132, 133 are so long that the two units are also at the maximum angular offset β _max 8, 10 of each pair stay connected.

It can be seen from FIG. 12b that the channels 135 have changed to the respective adjacent connecting groove 136 in comparison with FIG. 10b. As a result, a pressure side change has taken place in the second embodiment of the radial piston pump according to the invention. The pressure medium is now sucked in from the working connection B, which is now the low-pressure connection, and discharged into the working connection A, which is now the high pressure conclusion is. In the case of angular offsets β in the range between zero degrees and less than a / 2, on the other hand, the working connection B is the high-pressure connection and the working connection A is the low-pressure connection (cf. FIG. 10b). FIG. 13 shows a circuit diagram of the radial piston pump according to the two preceding embodiments. The electrical supply of the two electric motors 16 and 18 via a power grid and a

Feed unit 200 which generates direct current for a doubled intermediate circuit 202, of which - apart from the two electric motors 16, 18 - also other (not shown) consumers can be supplied. The two electric motors 16, 18 are supplied via respective frequency converter 204 from the intermediate circuit 202. A control circuit 206 actively controls the rotational speed of the two electric motors 16, 18. Thus, while in the hitherto described embodiments of a hydrostatic piston engine according to the invention, the displacement piston units are arranged on the two sub-rotors, are in the embodiment of Figures 14 to 21, which in turn is designed as a radial piston machine, the pistons 3 and 7 in the housing 1, ie in the stator. The housing 1 has in a first radial plane over 360 degrees with the same angular distance distributed a plurality of circular cylindrical first displacers 5, which are open in a radially inward direction and in which there are first piston 3 and can perform strokes. Further, the housing 1 has to be distributed in a second radial plane over 360 degrees with equal angular distance a plurality of circular cylindrical second displacers 9, which are like the first displacement 5 also in a radially inward direction open and in which are located second piston 7 and Can perform lifting movements. The number of first displacement 5 is equal to the number of second displacement 9. In addition, the axes of each of a first displacement 5 and a second displacement 9 are parallel to each other. These two displacements 5, 9 are therefore in the same ben through the axis of rotation 6 of the piston engine going axial plane. Two lying in the same axial planes displacements 5, 9 are connected by a compensation channel 50 at its bottom regardless of the position of the piston 3, 7 fluidly connected to each other.

According to the embodiments according to FIGS. 1 to 14, the exemplary embodiment according to FIGS. 14 to 21 also has a first part rotor 2 and a second part rotor 4. Each sub-rotor 2, 4 has a hollow shaft 52, 53, with which it rotatably supported by bearings 51 on a not-shown and belonging to the stator axis. In addition, each partial rotor 2, 4 is operatively connected to an electric machine 16 or 18, which can operate both as an electric motor and as an electric generator. A with the hollow shaft 52, 53 fixedly connected flange 54, 55 of each partial rotor 2, 4 is radially outwardly and thus the mouths of the displacements 5, 9 facing provided with evenly distributed over the circumference of the cam 14, the number of which is greater than the number of first displacements 5 and the second displacement 9 is. The flanges 54 and 55 thus form the lifting elements of the hydrostatic piston engine. On the piston 3 and 7 rollers 1 1 are rotatably mounted, via which the pistons 3, 7 are supported on the cam 14. The hydrostatic piston machine shown in Figures 14 to 21 is thus one in which the pistons 3, 7 are supported on the inside. For the production of the various fluidic connections between the displacements 5, 9 and the working ports A and B of the piston engine no slot control as in the first two embodiments, but a valve control with a control valve assembly 56 is now provided. Namely, each pair of two fluidically interconnected continuously displacements 5, 9 is assigned its own 3/2 way valve 56, that is, a directional control valve with three connections and two switching positions, wherein a first connection with the two displacements 5, 9 and a second connection and a third connection via channels 57 and 58 extending in the housing are alternately connected to the working connection A or the working connection B of the piston engine. Depending on the position of a valve slide 59 of the 3/2-way valve 56, the two displacements 5, 9 are connected to the channel 57 or to the channel 58. The valve slide 59 is acted upon by a spring 60 in the direction of a switching position in which the displacements 5, 9 are connected to the channel 57. Under the action of the spring 60, the valve spool 59 follows the movement of a plunger 61, which is guided radially in the housing 1 and cooperates with control cam 65, which are present in addition to the cam 14 on the flange 54 of the partial rotor 2. The control cams 65 are associated with the cam 14 of the flange 54 so that during a displacement stroke of the piston 3, ie during a movement of the piston 3 radially outward, the displacements 5, 9 with the channel 57 and a sip or suction stroke, ie in a movement of the piston 3 radially inwardly, the displacements 5, 9 are connected to the channel 58.

The control valve assembly 56 may have two 2/2 way valves instead of a 3/2 way valve 56. If only one 1-quadrant operation is provided as the pump for the piston engine, with one working connection being the pressure connection and the other working connection being the suction connection, the control valve arrangement 56 can also consist of two simple passive check valves 80, 81. See the fourth embodiment of Figures 22 and 38 and the fifth embodiment of Figure 23.

The channels 57 leading to the one port of the control valve assemblies 56 are all interconnected. Likewise, all channels 58 are interconnected. Where this connection is made, whether directly on the control valve assembly 56 or away therefrom, depends on design considerations. The channels 57 and 58 may in certain embodiments of a hydrostatic piston machine according to the invention directly be connected to the working ports A and B. See the sixth embodiment of Figure 24 and Figures 27 to 31.

In the exemplary embodiment shown in FIGS. 14 to 21, the second connections of all the control valve arrangements 56 are connected via the channel 57 to a first connection and the third connections of all control valve arrangements 56 are connected via the channel 58 to a second connection of a changeover valve arrangement 70 likewise accommodated in the stator. This includes a 4/2 way valve 70, the third port and the fourth port are formed by the working ports A and B. It is possible to provide only a single change-over valve arrangement 70 or else a plurality of parallel-connected and identically actuated change-over valve arrangements 70.

Each change-over valve arrangement 70 comprises a valve slide 71, which in the first switching position connects the working connection A with the channel 57 and the working connection B with the channel 58 and in the second switching position the working connection A with the channel 58 and the working connection B with the channel 57. The valve spool 71 assumes either the first switching position or the second switching position as a function of the relative rotation and thus as a function of the angular offset β between the first sub-rotor 2 and the second sub-rotor 4. Towards the first switching position, the valve slide 71 is loaded by a spring 72. Against the spring 72, it is supported on a ring 73 which in turn is supported by a plurality of evenly distributed over the circumference of the flange 55 of the partial rotor 4 and axially guided in this ram 74, which protrude beyond the flange 55 and with axially projecting cam 75 on Flange 54 of the partial rotor 2 cooperate. When the one or more rams 74 run onto a cam 75, they lift up the ring 73 and all existing valve spools 71 reach the second switching position. A cam 75 extends in the circumferential direction about the same angle as a cam 14 and with respect to the plunger 74 is arranged so that starting from positions of the sub-rotors 2 and 4, in which a cam 14 on the sub-rotor 2 and a cam 14 on the sub-rotor 4, with two pistons 3 and 7 interact axially, which are located in two permanently interconnected lifting chambers 5 and 9, axially exactly

behind one another, up to positions in which the two sub-rotors 2, 4 are angularly offset from one another by half a cam 14 (β <a / 2), the valve slide 71 occupies the position shown in FIG. 14, and the working port A with the channel 57 and the working port B is connected to the channel 58. If the partial rotors 2, 4 are rotated further than a half cam 14 (β> a / 2), the plungers 74 run on the cams 75, and the association between the working ports A and B and the channels 57 and 58 is reversed, and the pressure medium flow through the piston engine is reversed from the range up to a half cam 14 (β <a / 2). Thus, the piston machine can be operated without reversing the direction of rotation in both directions of flow both as a pump and as a hydraulic motor, ie in a 4-quadrant operation.

The stroke volume has changed from a maximum positive value for the angular offset β = 0 degrees above the value 0 for the angular offset β = 180 degrees to a maximum negative value for the angular offset β = 360 degrees. By further increasing the angular offset β, the value of the stroke volume can be reduced again because the cams 75 extend over the same angle as the cams 14. Of course, the value of the stroke volume can also be reduced by taking the angular offset β starting from 360 Degrees again reduced. If one does not want to go beyond 360 degrees with the angular offset β and does not change the angular offset β between the two partial rotors 2, 4 by solely short-term slower running or by a single short-term faster running of one partial rotor, but by a slower running of the one partial rotor for short periods a change in the angle offset in the one rich and slower running of the other sub-rotor for a change in the angular offset in the other direction or by slower slow running of a sub-rotor for a change in the angular offset in one direction and short-time faster run of the same sub-rotor for a change in the angular offset in the other Direction, it is sufficient if the cams 75 only extend over half the angle a / 2 of the cam 14 and it is sufficient if exactly as many cams 75 as plunger 74 are present. Various constellations of the cams 14 of the sub-rotors 2, 4 and the control valve assemblies 56 are shown in FIGS. 18 to 21, as they exist in certain operating states of the piston engine shown in FIGS. 14 to 17. According to Figures 18 and 19, the two part rotors 2, 4 with their cams 14 are not angularly offset. The direction of movement of the cams 14 with respect to the pistons 3, 7 is indicated by arrows. In the state of movement of Figure 19, the two pistons 3 and 7 of a pair of displacement piston units 8, 10 run in a delivery from a bottom dead center of the cam 14, which they had reached at the same time, a flank of two cams 14 and reach the bottom dead center at the same time. During their movement, the free volume of the displacements 5, 9 decreases, from which in the given switching positions of the valves 56 and 70 pressure medium in the working port B is displaced.

In the state of movement according to FIG. 18, the two pistons 3 and 7 of a pair of displacement piston units 8, 10, having reached the top dead center of two cams 14 at the same time, have passed in a suction stroke, an edge of the cams 14 down and reach the same time the bottom dead center. During their movement, the free volume of the displacements 5, 9, in which ben switching positions of the valves 56 and 70 pressure medium from the working port A forth, which may be connected to a tank, is sucked.

In comparison of Figures 18 and 19 it can be seen that in the transition from the delivery stroke to the intake stroke, the 3/2 way valve 56 has changed its switching position under the influence of a control cam 65.

According to FIG. 20, the cams 14 of the first partial rotor 2 are offset relative to the cams 14 of the second partial rotor 4 by half an angular extent α of a cam 14 (β = a / 2). The pistons 3 and 7 of a pair of displacement piston units 8, 10 then move in the displacements 5, 9 in opposite directions, so that the amount of pressure medium, the one piston 3, 7 when running up to a flank of a cam 14th displaced from bottom dead center to top dead center, completely for filling the increasing free volume of the displacement 5, 9 of the other piston 3, 7 is needed. It is thus promoted no pressure medium.

In FIG. 20, the 4/2-way valve 70 still assumes the same switching position as in FIGS. 18 and 19. If the angular offset .beta. Between the two sub-rotors 2 and 4 with respect to the angular offset .beta. In FIG. 20 is then increased by half the angular extent a / 2 of a cam 14 increases, the pin 74 runs on a cam 75 and brings the 4/2 way valve 70 in its second switching position. During the suction stroke, pressure fluid now flows from the working port B into the displacement. During the delivery stroke of the pistons 3 and 7, pressure medium is displaced into the working port A. In this case, the delivery volume, ie the amount of pressure medium delivered per revolution of the hollow shafts 52, 53, increases up to an angular offset β of a full angular extent α of a cam 14 (β = a) shown in FIG. As well as a pump, a hydrostatic piston machine with the valves 56 and 70 can also be operated as a hydraulic motor. It is a 4- Quadrant operation possible, with no reversal of rotation is necessary to swap the working ports in terms of high pressure and low pressure, or no swapping of the working ports in terms of high pressure and low pressure is necessary to reverse the direction of rotation.

Figures 22 to 24 show schematically three embodiments with simpler control valve equipment, which are then subject to restrictions on the operation. In the embodiment of Figure 22, two simple passive check valves 80 and 81 are inserted between the working ports A, B and the displacements on the two pistons 3 and 7 of a pair of displacement piston units, wherein the check valve 80 from the displacements to the working port A and opens the check valve from the working port B to the displacements. The check valve 80 acts as a pressure valve and the check valve 81 as a suction valve. The hydrostatic piston machine according to FIG. 22 can thus be operated only as a pump whose pressure connection is the working connection A and whose suction connection is the working connection B. So it is only a 1-quadrant operation possible.

The exemplary embodiment according to FIG. 23 is supplemented by the 4/2 directional control valve 70 with respect to that according to FIG. Depending on the switching position of the 4/2-way valve 70, the working connection A or the working connection B is now the pressure connection and the other working connection is the suction connection. The hydrostatic piston machine according to FIG. 23 can thus also be operated only as a pump, but each working connection can be the pressure connection. So it is a 2-quadrant operation without change of direction of the drive shafts possible. In the embodiment of Figure 24, the two passive check valves 80 and 81 of the embodiment of Figure 22 by the actively controllable 3/2 way valve 56 replaced. It is possible to operate in pump mode and in motor mode, and when reversing the direction of rotation, 4-quadrant operation is possible. In the embodiment according to FIGS. 25 and 26, the partial rotors 2 and 4 carry cams 14 which point in the axial direction. Accordingly, the pistons 3 and 7 of the arranged in a stator displacement piston units are axially aligned and perform strokes in the axial direction, ie parallel to the axes of rotation or to the axis of rotation 6 of the part rotors 2 and 4. In each case a displacement with a piston 3, which cooperates with the cam 14 on the sub-rotor 2, and a displacement with a piston 7, which cooperates with the cam 14 on the sub-rotor 4 are permanently fluidly connected to each other in a manner not shown. Associated with each pair of fluidically interconnected displacements is a control valve arrangement 56, which is controlled by control cams 65 on the outer circumference of the partial rotor 4. Of course, the control cams 65 may also be in the axial direction, with the control valve assembly 56 then being advantageously arranged so that the movable valve body 59 moves axially. The partial rotors 2 and 4 can be supported against each other so that an axial force compensation is obtained.

In operation, the pistons 3 and 7 of the hydrostatic units shown should be held on the rollers 1 1 on the cam track 14, so do not lift off from the cam track. This can be achieved, for example, by the fact that constantly from the outside a pressure in the terminals A or B or A and B is present, which requires a lower housing internal pressure. In this case, the Nachsaugventil 40 (see Figure 8) sucks advantageously from the channel A or B or A and B. The Nichtabheben can also be achieved in that under the piston springs are arranged, of which the pistons are held without form over the rollers on the cam track. Between the partial rotors 2, 102 and 4, 104 and the electric motors 16, 18, gearboxes can optionally also be interposed in order, for example, to realize "kinetic buffering" or to equalize the engine speed to the required rotor speed.

It is also possible to use a partial rotor by means of a variable-speed electric drive and the other partial rotor by means of a mechanical drive, for example winch drive in the maritime sector.

The valve 59 (see figures from Figure 14) can also be replaced by two single 2/2-way valves, each of which is actuated by its own cam 65. One valve then works as a pressure valve and the other as a suction valve. With such a design, the valves can be adjusted separately from one another and thus the control times can be influenced separately from one another.

Figure 27 shows a half longitudinal section along and above the axis of rotation 6 of the sixth embodiment of Figure 24. The two displacements 5, 9 permanently connected to each other via the channel 50, wherein viewed in the axial direction between the two part rotors 2, 4 the respective Control valve assembly forming 3/2-way valve 56 is arranged. It serves to connect the two pressure chambers 5, 9 alternately via the channel 50 either to the first working connection A or to the second working connection B. Trained as a valve spool 59 control valve body of the 3/2-way valve 56 is switched in the radial direction via the plunger 61 in response to the control cam 65. In the illustrated by the spring 60 biased basic position of the valve spool 59 of the radially inner end portion of the plunger 61 between two control cam 65, whereby the 3/2-way valve 56 connects the two displacements 5, 9 with the first working port A. By rotation of a Control rotor 208, on whose outer circumference a plurality of control cam 65 are evenly distributed, the valve spool 59 can be pushed against the spring 60 radially outward, whereby the two displacements 5, 9 are shut off against the working port A and connected to the working port B.

In the position shown in FIG. 27, the two flanges 54, 55 of the two partial rotors 2, 4 forming the lifting elements have no angular offset (β = 0), so that the pistons 3, 7 of each pair are moved synchronously via the cams 14. If an angular offset β is set via the two electric motors 16, 18 in order to reduce the stroke volume, the control rotor 208 automatically adjusts by means of a toothed wheel 210 to an angular offset which corresponds exactly to half the angular offset of the two partial rotors 2, 4. Thus, the control rotor 208 always has half an angular offset β / 2 with respect to the first flange 54 and a half angular offset β / 2 with respect to the second flange 55. The toothed wheel 210 is rotatably mounted about a radial axis of rotation 212 in the control rotor 208 and meshes on the one hand with the circumference of the first flange 54 distributed teeth and on the other hand with distributed on the circumference of the second flange 55 teeth. The control rotor 208 is - comparable to the storage of the two partial rotors 2, 4 - mounted on a bearing 51 relative to the housing 1 serving as a stator. By means of the control rotor 208 and the associated mechanical switching of the respective 3/2-way valve 56, a correct switching of the respective pair of lifting chambers 5, 9 is alternately to the working connection A, B and to serve as the high-pressure connection even at different angular offsets the serving as a low-pressure connection working port B guaranteed.

FIGS. 28 to 31 each show, in a diagrammatically developed representation, the relationship or the association between the first flange 54, illustrated above, with its cam 14, shown below In this case, FIG. 28 shows an angular offset β = 0, FIG. 29 shows an angular offset β> 0, FIG. 30 shows an angular offset β = a / 2 and FIG. 31 shows an angular offset ß> a / 2. For each operating state according to FIGS. 28 to 31, a stroke volume diagram is shown below. More specifically, the curves of the first swept volume 214 of the first unit 8, the second swept volume 215 of the second unit 10, and the curve of the total effective swept volume 216 of the pair of units 8, 10 are shown. The angular offset β of the two flanks 54, 55 is shown in the respective unwound representations as an offset of the cams 14 of the second flange 55 with respect to those of the first flange 54 (in FIGS. 28 to 31 to the right).

In the figures 28 to 31, respectively, the roller 1 1 of the first piston 3 and the roller 1 1 of the second piston 7 are shown. In each operating state, it is assumed that the roller 1 1 of the first piston 3 is supported straight at the top dead center of a cam 14 of the first flange 54, so that in relation to the position of the roller 1 1 of the second piston 7 can be seen. At an angular offset ß = 0 and the roller 1 1 of the second piston 7 at top dead center, at an angular offset of ß 0 according to Figures 29, 30 and 31, the roller 1 1 of the second piston 7 is always arranged radially further inside. For each of the four operating states according to FIGS. 28 to 31, the position of the control cam 65 of the control rotor 208 is also shown. As a result of the above-described automatic adjustment of the control rotor 208 to an angular offset of β / 2, the control cams 65 always assume an intermediate position.

The respective 3/2-way valve 56 of each pair of units 8, 10 is fixedly arranged together with the displacements 5, 9 in the serving as a stator housing 1 and is switched in the manner described above via the control cam 65 against the spring 60. According to Figure 28 add up at the angular offset β = 0, the stroke volumes 214, 215 at an effective stroke volume 216 which has been doubled compared to FIG. 30, the two stroke volumes 214, 215 are such that the effective stroke volume 216 becomes zero. The angular offset β according to FIG. 29 and the angular offset β according to FIG. 31 produce effective stroke volumes 216, which are reduced compared to the stroke volume 214, 215 of each individual piston 3, 7.

FIG. 32 shows a section of a longitudinal section of an eighth exemplary embodiment with a control rotor 218 which (in accordance with the control rotor 208 of the preceding exemplary embodiment) is always positioned between the two sub-rotors 2, 4 in the circumferential direction such that it always has half the angular offset. 2 on the one hand with respect to the first part rotor 2 and on the other hand with respect to the second part rotor 4 has. In the eighth embodiment, a slot control is realized via the control rotor 218. For this purpose, the control rotor 218 has two abutting abutment surfaces 220, 221 which are arranged parallel to one another and perpendicular to the axis of rotation 6 of the radial piston machine. FIG. 33 shows the control rotor 218 of the eighth exemplary embodiment in a view of the first abutment ring surface 220. In this case, the toothed wheel 210 can be seen, which is mounted rotatably in the control rotor 218 and ensures the described positioning of the control rotor 218. The two abutment ring surfaces 220, 221 are connected to one another via passage recesses 222, 224. More specifically, radially circumferentially distributed radially outer passage recesses 222 and uniformly circumferentially distributed radially inner passage recesses 224 are provided. All passage recesses 222, 224 extend over a same angular range of the control rotor 218 and have the shape of a circular arc whose common center lies on the axis of rotation 6. In FIG. 32 it is shown that the outer through-passages 222 open and close a connection between the channel 50 and the first working port A, while the inner through-passages 224 open and close a connection of the channel 50 with the second working port B. For this purpose, four orifice seals 226, 227, 228, 229 are provided on the housing 1, of which a first outer orifice seal 226 and a first inner orifice seal 227 sealingly abut the first Anlageringfläche 220 of the control rotor 218, while a second outer orifice seal 228 and a second inner Mouth seal 229 sealingly abut the second Anlagingfläche 221 of the control rotor 218. The first outer orifice seal 226 is connected to the first working port A, while the second inner orifice seal 229 is connected to the second working port B. The first inner muzzle seal 227 and the second outer muzzle seal 228 are both always connected to the channel 50 and therefore always to both displacements 5, 9 of the pair of units 8, 10.

Figures 34 to 37 show the eighth embodiment of Figure 27 in four different operating conditions. In this case, the angle offset β = 0 in FIG. 34, the angular offset β> 0 in FIG. 34, the angular offset β = α / 2 in FIG. 36 and the angular offset β> α / 2 in FIG.

In the operating state with angular displacement ß = 0 according to Figure 34, the two pistons 3, 7 and their rollers 1 1 are arranged behind each other, so that only one piston 3, 7 and a roller 1 1 is shown. In a pump operation and in a direction of rotation of the flanges 54, 55 in the clockwise direction, the two pistons 3, 7 of the right in Figure 34 pair are urged radially outward, so that this pair performs a Verdrängerhub. Via one of the outer through-passages 222, the considered pair is connected to its associated first outer orifice seal 226, whereby the displaced pressure medium is conveyed to the working port A. and thus the first working port A forms the high-pressure side HD of the radial piston machine operated as a pump. The middle pair of pistons 3, 7 shown in FIG. 34 has reached the top dead center of a cam 14 during the snapshot shown and is not connected at this moment by the control rotor 218 to either the first working port A or the second working port B. The left-hand pair of pistons 3, 7 in FIG. 34 is moved radially inward and is correspondingly connected via one of the inner through-passages 224 to its second inner orifice seal 229. Since this is connected to the second working line B (see Figure 32), the considered pair of pistons 3, 7 is connected to the low pressure side ND of the axial piston pump.

In the operating states according to FIGS. 34, 35 and 36, the outer through-passages 222 of the control rotor 218 thus control the connections to the high-pressure side HD, while the inner through-passages 224 control the connections to the low-pressure side ND. In contrast, in the operating state according to FIG. 37, the angular offset β has been set to a value which is greater than the angular extent of half a cam 14 (β> a / 2). This results in a pressure side change at the two working ports A, B, so that the conveying direction of the radial piston pump - with unchanged direction of rotation of the flanges 54, 55 in a clockwise direction - is changed.

In Figure 36, the angular offset β = a / 2 is set, thereby setting the total effective displacement 216 of each pair of units to zero. Although the pairs of units are alternately connected to the two working ports A, B via the slot control of the control disc 218, no volume is delivered to any of these working ports A, B since the two units 8, 10 of each pair only push pressure means back and forth , The radial piston machines of the sixth embodiment according to FIGS. 24 and 27 to 31 and of the eighth embodiment according to FIGS. 32 to 37 can in principle also be operated as a motor and are able to realize a change in the pressure side. Thus, the two embodiments mentioned are 4-quadrant capable.

FIG. 38 shows a detail of a longitudinal section of the fourth exemplary embodiment according to FIG. 22. The housing 1 serving as a stator corresponds to that of the eighth exemplary embodiment according to FIG. 32. Thus, the housing 1 can be used for both exemplary embodiments. Compared to the eighth embodiment of the control rotor 218 is omitted. Furthermore, the mouth seals 226, 227, 228, 229 omitted and replaced by a respective stopper. The two displacements 5, 9 and the channel 50 of each pair are - as already explained with reference to Figure 22 - connected via the two passive check valves 80, 81 to the two working lines A, B. In this case, the check valves 80, 81 define via their opening directions a conveying or swallowing direction of the radial piston machine. For example, in pump operation, the second working port B is the low-pressure side ND, from which the pressure medium is sucked into the two displacement chambers 5, 9 via the respective non-return valve 81. When displacing from the two displacements 5, 9, the pressure medium is conveyed via the check valve 80 to the first working port A, which thus forms the high-pressure side HD. FIG. 39 shows a longitudinal section of a ninth embodiment along the axis of rotation 6 with a control rotor 232 which, together with the housing-side orifice seals 226, 227, 228, 229, realizes the slot control, which is basically the same as in the exemplary embodiment according to FIG. To set the half-angular offset ß / 2 see between the two flanges 54, 55, two opposing gears 210 are provided in the control rotor 232, which is a respect to the Control rotor fixed radial axis of rotation 212 are rotatable. The two gears 210 mesh with a first gear 234 which is rotatably connected to the first flange 54, and with a second gear 235 which is rotatably connected to the second flange 55. All four gears 210, 234, 335 are bevel gears and realize in a particularly secure manner the half angle offset ß / 2 of the control rotor 232nd

A variant of the embodiment according to FIG. 39 is shown in FIG. 41. In this variant, the control rotor 232 is radially outwardly provided with a toothing 250 and meshes with a toothed wheel 251, which is rotationally connected to a shaft 252, which is mounted in an extension of the housing 1 and by a non-illustrated, unregulated drive, for example, by an unregulated electric motor or by a wind turbine is driven. As in the exemplary embodiment according to FIG. 39, the flange 54 is connected to a speed-controllable electric motor 16 (not shown in FIG. 41) or the flange 55 to a speed-controllable electric motor 18 (not shown). It can also be connected to each flange with an electric motor. Via the existing one electric motor 16 or 18 or via the two existing electric motors 16 and 18, the volume adjustment takes place by rotating the two flanges against each other. The rotational speed of the gear 251 is detected. According to the rotational speed, one of the electric motors 16 or 18 rotates or rotates both of the electric motors 16 and 18 in synchronism with the flanges 54 and 55, thereby equalizing nonuniformities in the torque.

To adjust the stroke volume, if only a controllable electric motor 16 or 18 is present, the rotor is slowed down or accelerated by the one electric motor for a short time, and then run synchronously again. The differential movement of one flange is transmitted in opposite directions via the bevel gear 210 to the other flange. If two controllable electric motors are available, one brakes one and the other one accelerates briefly or is switched load-free. If two controllable electric motors 16 and 18 are present, they may be made weaker than a single existing controllable electric motor. FIG. 40 shows a detail of a longitudinal section of a tenth embodiment. The control valve assembly 56 of the pair of displacements 5, 9 is formed via two solenoid-operated switching valves 237, via which the channel 50 is connected to the two working ports A, B. Each switching valve 237 has a spring and a solenoid, both of which are arranged on the same side of the valve body. Each switching valve 237 is formed inside its valve housing 238 as a 3/2-way valve, while it is formed on the outside as a 2/2-way valve. In this case, each switching valve 237 serves as a shut-off valve of the two displacements 5, 9 to the respective working port A, B. The two switching valve 237 of each pair must be switched quickly and precisely each other. The respective time for switching is shown in the stroke volume diagram of Figure 37. Whenever the course of the first stroke volume 214 of the first unit 8 intersects with the profile of the second stroke volume 215 of the second unit 10, a maximum or a minimum results in the total effective stroke volume 216 of the pair. This means that at the times mentioned, of which only two are shown in FIG. 27, the pair of units 8, 10 change from suction to displacement or vice versa. Accordingly, both switching valves 237 of the respective pair of units must be actively switched at these times.

The number of cams 14 on the rotor or on the stator is at least one cam or larger than a cam. In a single cam, the cam track is realized by an eccentric circular cylinder. With this construction, adjustable high-pressure pumps (motors) with operating pressures up to, for example, 1000 bar could be built. Disclosed is a hydrostatic radial piston pump, the displacement piston units are connected in pairs hydraulically, and are divided into a first part rotor and a second part rotor. In one particular embodiment, the pistons of all pairs of displacement piston units are guided along a common cam lift cam curve. When operating as a motor can be adjusted by an angular offset between the two sub-rotors in the circulation of the two sub-rotors, the intake volume of the machine, since the one unit of each pair promotes a portion of the absorption volume of the other unit in this. When operating as a pump, the displacement of the machine can be adjusted via the angular offset, since the one unit of each pair receives part of the delivery volume of the other unit.

LIST OF REFERENCE NUMBERS

I housing / stator

2; 102 first part rotor

3 first piston

4; 104 second sub rotor

5 first displacement

6 rotation axis

7 second piston

8 first displacement piston unit

9 second displacement

10 second displacement piston unit

I I role

12 cam ring

14 cams

16 first electric motor / first electric machine

17 permanent magnet

18 second electric motor / second electric machine

19 winding

20, 22 output shaft

24a opening

24b opening

26 channel

28 second equalization channel

30 stop

32 connecting groove

40 check valve

42 pressure relief valve

43 groove

44 cones

50 compensation channel 51 bearings

52 first hollow shaft

53 second hollow shaft

54 first flange

55 second flange

56 control valve assembly / 3/2-way valve

57, 58 channel

59 control valve body / valve spool

60 spring

61 pestles

65 control cam

70 changeover valve arrangement / 4/2-way valve

71 Diverter valve body / valve spool

72 spring

73 ring

74 pestles

75 cams

80, 81 passive check valve

132, 133 Connecting groove

134 channel

135 channel

136 connecting groove

200 feed unit

202 DC link

204 frequency converter

206 control loop

208 control rotor

210 gear

212 radial axis of rotation

214 first stroke volume

215 second stroke volume 216 effective displacement

218 control rotor

220 first investment ring area

221 second investment ring

222 outer passage recess

224 inner passage recess

226 first outer muzzle seal

227 first inner muzzle seal

228 second outer muzzle seal 229 second inner muzzle seal

230 plugs

232 control rotor

234 first gear

235 second gear

237 switching valve

238 valve housing

250 toothing

251 gear

252 wave

α angular extension of a cam ß angular misalignment

ß _m ax maximum angular misalignment

A, B work connection

HD high pressure / high pressure side

ND low pressure / low pressure side

PA piston of the first part rotor

PB Piston of the second part rotor V Stroke volume

Claims

claims

1 . Hydrostatic piston machine with adjustable displacement, with two working ports (A, B), with a rotor and with a stator (1) and with a plurality of in the rotor or in the stator (1) located displacements (5, 9) in the first Displacement chambers (5) and in second displacements (9) are divided, each first displacement (5) is permanently fluidically connected to a second displacement (9), and with first piston (3; PA), each on a lifting element ( 12; 54) and in the first Hubräu- men (5) perform lifting movements, and with second piston (7; PB), each supported on a lifting element (12; 55) and perform in the second displacements (9) lifting movements characterized in that the rotor comprises a first part rotor (2; 102) whose rotation relative to the stator (1) causes strokes of the first pistons (3; PA) and a second part rotor (4; 104) whose rotation relative to the stator (1) causes strokes of the second pistons (7, PB), comprises, and that the two partial rotors (2, 4; 102, 104) with an adjustable to adjust the stroke volume angle offset (ß) to each other at the same speed are operable.

2. The hydrostatic piston machine according to claim 1, wherein the two sub-rotors (2, 4, 102, 104) and the stator are accommodated in a common housing (1) in which two drive shafts (20, 22, 52, 53), of which one with the one part rotor (2; 102) and the other with the other part rotor (4; 104) is rotatably mounted.

3. A hydrostatic piston machine according to claim 1 or 2, wherein the lifting elements (12, 54, 55) have a like plurality of evenly distributed over the circumference of the cam (14).

4. Hydrostatic piston engine according to claim 1, 2 or 3, wherein the number of first displacement (5) equal to the number of the second Displacement (9), and wherein in each case exactly one first displacement (5) and exactly one second displacement (9) are connected in pairs fluidly with each other.

5. Hydrostatic piston engine according to claim 4, wherein the interconnected displacement (5, 9) in operation with maximum displacement in pairs lying in the same axial plane lying side by side or, if they are and thus the pistons are located on the stator, in the same axial plane.

6. Hydrostatic piston machine after a previous one

Claim, wherein the one part rotor (2, 4, 102, 104) is coupled to a speed-controllable electric machine (16, 18).

7. Hydrostatic piston machine according to claim 6, wherein the rotational speed of the speed-controllable electric machine (16, 18) in dependence on the angular offset (ß) between the two sub-rotors (2, 4, 102, 104), which is preferably determined by a rotation angle sensor arrangement , via a control loop (206) is adjustable.

8. Hydrostatic piston machine according to claim 6 or 7, wherein the one part rotor (2; 102) with a variable in their rotational speed as a function of the angular offset (ß) between the two sub-rotors (2, 4, 102, 104) first electric machine (16) and the other sub-rotor (4; 104) are coupled to a second electric machine (18) which is preferably also adjustable in speed.

9. Hydrostatic piston machine according to one of claims 6 to 8, wherein an electric machine (16, 18), preferably the electric machine, the speed of which is controllable in dependence on the angular offset (β) between the two sub-rotors (2, 4; an asynchronous motor is rotatably coupled to a rotatable flywheel.

A hydrostatic piston machine as claimed in any preceding claim, wherein a drive shaft (20, 22, 52, 53) of an electric machine (16, 18) is integral with a part rotor (2, 4, 102, 104).

1 1. Hydrostatic piston engine according to one of the preceding claims with a high-pressure connection and with a low-pressure connection, the angular offset (β) being adjustable up to a maximum angular offset (β _m ax) equal to half the wavelength (a / 2) of a cam (14). equivalent.

12. Hydrostatic piston engine according to one of claims 1 to 10 with a first working port (A) and with a second working port (B), both as high-pressure port (HD) and as a low-pressure connection (ND) can be used, wherein the angular offset (ß) is adjustable up to a maximum angular offset (ß _ma x), which corresponds to the wavelength (a) of a cam (14).

13. Hydrostatic piston engine according to one of claims 1 to 10 with a first working port (A) and with a second working port (B), both as a high pressure port (HD) and as a low-pressure connection (ND) can be used, wherein the angular offset (ß ) is adjustable beyond an angular offset corresponding to the wavelength (a) of a cam (14).

14. Hydrostatic piston engine according to any preceding claim, wherein the stator (1) has a common lifting ring (12) or two lifting rings on which or at which with the same angular position uniformly cams (14) are formed, on which the first piston (3; PA) and the second pistons (7, PB) are supported, and wherein the first pistons (3; PA) in the first part rotor (2; 102) and the second pistons (7; PB) in the second part rotor (4; 104) are guided.

15. Hydrostatic piston engine according to one of the preceding claims, wherein between the two sub-rotors (102, 104) a slot control is provided, over which at an angular offset (ß) greater than half the wavelength (a / 2) of a cam ( 14), a pressure side change between two working ports (A, B) takes place.

16. The hydrostatic piston machine according to claim 1, wherein a plurality of first openings (24a, 24b) connected to a first working port (A) and a plurality of a second one adjoining the first part rotor (102) of the housing (1) Working connection (B) connected to the second openings (24a, 24b) are formed, and wherein the second part of the rotor (104) located, the second displacements (9) during one revolution of the partial rotors (102, 104) over in the first part rotor (102) formed Channels (134) are alternately connectable to the first openings (24a, 24b) and to the second openings (24a, 24b).

17. Hydrostatic piston engine according to claim 15 or 16, wherein the slot control comprises circular arc-shaped connecting grooves (136) which are arranged between the displacements (9) of the second partial rotor (104) and the channels (134) in a first abutment region between the two partial rotors (102 , 104), and dimensioned such that at an angular offset (β) which is greater than half the wavelength (a / 2) of a cam (14), the pairs of displacements (5, 9) each with a adjacent channel (134) and thus with an adjacent opening (24a, 24b) are connected.

18. Hydrostatic piston engine according to one of claims 12 to 17, wherein the first displacements (5) in each case via one or two kreisbo- genförmige connecting grooves (132, 133) formed in a second abutment region between the two sub-rotors (102, 104) are connected to the respective second displacement (9), wherein the connecting grooves (132, 133) are dimensioned such that a Hubraumpaar remain in pressure medium connection up to the maximum angular misalignment (ß _ma x).

19. Hydrostatic piston engine according to one of claims 1 to 13, wherein the first lifting element (54) on the first part rotor (2) and the second lifting element (55) on the second part rotor (4), wherein the displacement (5, 9) and the first pistons (3) and the second pistons (7) are located in the stator (1), and for each pair of permanently interconnected displacements (5, 9) there is a control valve assembly (56) over which the pair of permanent interconnected lifting chambers (5, 9) with two working ports (A, B) is connectable.

20. A hydrostatic piston machine according to claim 19, wherein the control valve assembly (56) comprises at least one movable control valve body (59) which is actuated in response to the angular offset (ß) of the one part rotor (2), and a pair of permanent with each other Connected displacements (5, 9) in dependence on the switching state of the control valve assembly (56) with one working port (A) or with the other working port (B) is connectable.

21. A hydrostatic piston engine according to claim 19 or 20, wherein there is a changeover valve arrangement (70), depending on the switching state, two ports of the control valve assemblies (56) are connectable in a first manner or in a reversed manner to the two working ports (A, B).

22. A hydrostatic piston machine according to claim 21, wherein the

Change-over valve arrangement (70) at least one movable Umschaltven- Tilkörper (71) which is actuated in dependence on the angular offset (ß) between the two sub-rotors (2, 4).

A hydrostatic piston engine according to claim 22, wherein the changeover valve body (71) is operable via at least one plunger (74) guided in one sub rotor (4) and cooperating with a cam (75) on the other sub rotor (2).

24. A hydrostatic piston machine according to claim 19 or 20, wherein the control valve assembly (56) via a control rotor (208; 218; 232) is operable, which is so coupled to the sub-rotors (2, 4) that it always half the angular offset (ß / 2).

25. Hydrostatic piston engine according to claims 20 and 24, wherein on the control rotor (208) control cam (65) are formed, via which the control valve body (59) is actuated.

26. The hydrostatic piston machine according to claim 1, wherein the first lifting element (54) is located on the first part rotor (2) and the second lifting element (55) is on the second part rotor (4), and wherein the first pistons (3) and the second pistons (7) are located in the stator (1), wherein the stator (1) surrounds the partial rotors (2, 4) radially on the outside, and wherein the pistons (3, 7) extend inward in the radial direction on the lifting elements ( 54, 55) are supported.

27. A hydrostatic piston machine according to claims 15 and 26, wherein the slot control is formed on a control rotor (218; 232) which is coupled to the sub-rotors (2, 4) such that it always has half the angular offset (β / 2) ,

28. A hydrostatic piston machine according to claim 27, wherein the control rotor (218; 232) has a control disk on which the slot control by means of arcuate Durchgangsausnehmungen (222, 224) and by both sides of the control disk on the stator (1) arranged openings (226, 227, 228 , 229) is formed.

29. Hydrostatic piston machine according to claim 24, 25, 27 or 28, wherein the half angular offset (ß / 2) of the control rotor (208; 218; 232) via a meshing engagement with the part rotors (2, 4) is realized.

30. Hydrostatic piston machine according to claim 29, wherein the control rotor (232) can be driven by an uncontrolled drive motor and the drive of the two sub-rotors (2, 4) via the control rotor (232) takes place and wherein the Hubvolumenverstellung by driving the part rotors (2, 4 ) via controlled electric motors.

31. Hydrostatic piston machine according to one of the preceding claims with a stop (30) which is provided between the two rotors (2, 4, 102, 104) for limiting the angular offset (β).

32. Hydrostatic piston engine according to one of the preceding claims with a Nachsaugeinrichtung (40) for the displacement piston units (8, 10).

33. Hydrostatic piston engine according to one of the preceding claims with a pressure-securing device (42) for the displacement-piston units (8, 10).