EP2510192A1

EP2510192A1 - Hydrostatic radial piston machine

Info

Publication number: EP2510192A1
Application number: EP10790918A
Authority: EP
Inventors: Jürgen Berbuer
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-12-11
Filing date: 2010-12-07
Publication date: 2012-10-17
Anticipated expiration: 2030-12-07
Also published as: DE102009054548A1; CN102652206A; DE202010013078U1; US20130145929A1; CN102652206B; WO2011070019A1; US9784252B2; EP2510192B1

Abstract

A hydrostatic radial piston machine has: a radial cylinder piston block (9) with cylinder bores (11) which emanate from an outer circumferential surface of the radial cylinder piston block, extend into the interior of the latter and are arranged distributed over the circumference thereof; a number of pistons (13) which corresponds to the number of cylinder bores; a cam ring (4) which is arranged eccentrically with respect to the radial cylinder piston block, surrounds the radial cylinder piston block circumferentially and on the inner circumferential surface (17) of which ends of the pistons which face away from the radial cylinder piston block are supported movably during the rotational movement of the radial cylinder piston block; and two control plate bodies (30, 32) which extend in each case with an end surface which faces the radial cylinder piston block towards a centre plane of the radial cylinder piston block, which centre plane is perpendicular with respect to the rotational axis, beyond a plane which is defined by an end surface, facing the respective control plate body, of the radial cylinder piston block at its point with the greatest axial width. Each control plate body has a bearing region, in which radially acting forces can be transmitted to a respective mating surface in the housing (2) or a housing cover (3) mounted in the latter.

Description

Hydrostatic radial piston machine

description

introduction

The invention relates to a hydrostatic radial piston machine comprising a housing, a cylinder star rotatably mounted in the housing about an axis of rotation and having a number of bores which extend from an outer surface of the cylinder star into its interior and are distributed over its circumference, one of the number of holes corresponding number of pistons which are slidably disposed in the bores and each define a working space for a hydraulic fluid together with the associated bore, an eccentrically arranged to the cylinder star cam ring which surrounds the cylinder star circumferentially and on the inner circumferential surface itself the cylinder star facing away from the piston during the rotational movement of the cylinder star movably support, two control mirror bodies having a total of at least two control cross sections, at least one of which with the inlet channel and at least one other with the off Lasskanal communicates, wherein both control mirror bodies each extend with a cylindrical face facing the end face on a plane perpendicular to the axis of rotation of the cylinder star to a plane beyond, from one of the respective control mirror body facing end face of the cylinder star in its place with the largest axial width is defined, one of the number of bores of the cylinder star corresponding number of arranged in the latter passage channels, which - depending on the rotational position of the cylinder star in the cam ring - each have a working space with a corresponding inlet channel with the control cross-section or with the with the Auslasska- Nal corresponding control cross section connect or can be closed by a located on the control mirror body closure surface.

State of the art

Radial piston machines, i. Radial piston pumps and radial piston motors can be subdivided, inter alia, according to how soft the hydraulic fluid is supplied to the work spaces in the cylinder star. From EP-A-0 401 408 it is known that the supply and discharge of the hydraulic fluid over a stationary, i. connected to the housing so-called control pin is done. Disadvantages of this very widespread design are that only relatively narrow flow channels (inlet and outlet channel) can be realized within the control pin and that due to the axially out of the control pin flow channels, the mechanical bending load of the control pin is quite high. As an advantage of this known construction can be stated that the bearing of a drive or output shaft is hardly loaded. On the other hand, there is a problem with the fit between the outer surface of the control pin and the inner surface of the rotating cylinder star. There is by design no zero gap possible, the leakage increases in the third power with the running play, resulting in larger leakage rates in particular with progressive wear. In addition, the previously known principle of the control pin-cylinder star fit is sensitive to dirt particles contaminated hydraulic fluids and temperature jumps. An alternative principle of the supply / removal of the hydraulic fluid to / from Zylinderstem is known from the publications DE-A-1 81 2 635, DE-A-24 52 092, DE-A-41 23 674 and DE-A-41 23 675 , In the construction disclosed in these documents is the control mirror body, which may also be integral with the housing, axially adjacent to the cylinder star. Problems with this type of construction are the large forces acting in the axial direction and their permanent low-wear support. In addition, the radial reaction forces from the hydraulic pressure on the shaft and must be absorbed by the shaft bearing.

A radial piston machine of the type described above is known for example from US-A-3,951,044. The machine disclosed therein has two control mirror bodies which are arranged on opposite sides of the cylinder star and which have a spherical shape on the side facing the cylinder star which interacts with an analogous calotte-shaped shape of the opposite side surfaces of the cylinder star (see FIG. in particular the local figure 4). In order to avoid jamming and friction between the control mirror bodies and the cylinder star during operation of the machine, in the known machine at least one control mirror body is limited in all directions, ie both in the axial and in the radial direction, movable. As a result, the rotating shaft connected to the cylinder star has to absorb the radial forces arising during operation due to the hydraulic pressures. This in turn leads to increased construction costs for the shaft and its storage and to potential wear.

The same principle of avoiding possible misalignments in the fit between the cylinder star and the control mirror body (s) due to the possibility of a radial displacement of at least one control disk body is also due to the machines according to DE-A-1 776 238 and US Pat. A-3, 122, 104. In the no eccentrically arranged but a elliptically shaped cam having double-stroke machine (two piston strokes per revolution) according to US-A-3, 122, 104 resulting from this due to the symmetry and the mutually canceling radial forces no problem. In the case of single-stroke machines with an extrentric lifting ring, however, the known principle leads to considerable friction and great demands on the shaft bearing. For this reason, the solutions according to the three above-mentioned earlier documents have found no input in practice.

OBJECT The object of the invention is to propose a radial piston machine in which the hydraulic forces can be fully hydrostatically relieved and stably supported.

solution

Based on a radial piston machine of the type described above, the underlying object is achieved in that each control plate body has a bearing area in which radially acting forces can be transmitted to a respective mating surface in the housing or a housing cover mounted therein.

In the context of the present invention, a control-plate body can be understood as meaning either a separate component in comparison with the housing, or a design integrally connected to the housing or a housing cover. A control mirror body must not be traversed by the hydraulic fluid, which may be the case when in a single control mirror body both control cross sections, ie both for the supply and the discharge of the hydraulic fluid from the cylinder chambers, whereas the other control mirror body no function in relation to fulfills the fluid supply of the cylinder star. The term control mirror body is therefore geometrically and mechanically understood in the present sense and not necessarily in relation to a flow of hydraulic fluid. Decisive is an abutment against the cylinder star in the axial direction.

According to the invention is - viewed in the axial direction - not only an intervention of the two control mirror body in the cylinder star before, but also a derivative of the radial forces on the control mirror body. In an axial section of the two abovementioned components, these thus overlap, with the control plate bodies projecting in a region lying radially further in the direction of the axial center of the cylinder star, so that a region of the cylinder stem located radially further outwardly virtually covers the two control plate bodies. Due to the inventive storage of the control mirror body is a complete hydrostatic discharge of the hydraulic forces occurring during operation and a stable support thereof via the housing or the housing cover, possible. Due to the symmetrical arrangement of the two control mirror body with respect to a central plane of the cylinder star, the hydraulic forces acting in the radial direction in the areas of the opposing control mirror body, in which they protrude into the cylinder star, initially by obliquely to the axis of rotation extending and opposite forces intercept. Each control disk body extending into the cylinder star thus fulfills the function of a "collar" known from architecture, figuratively speaking and in an axial section view, whereas in each case the area of the cylinder star, in which the width is radially outward - increases as a species

"Capstone" acts, which converts radial compressive forces in a pair of oppositely biased forces, the radial component in turn are each derived from the opposite control mirror bodies in this superimposed housing or housing cover.

In contrast, the control mirror body at radially extending separation level in the control cross sections, ie in the interface between the control mirror body and cylinder star, disc-shaped and have only perpendicular to the axis of rotation extending end surfaces. Due to this design, a support during operation occurring radial forces on the control mirror body is impossible. The same applies to spherical see or conical / conical control mirror body, but can not transmit any radial forces on the housing or its cover for lack of appropriate storage. Here, the invention provides a remedy by the intermeshing of the cylinder star and the control disk body and their mounting in the housing or housing cover, which leads to a particularly high compressive strength of the radial piston engine according to the invention. A further advantage of the invention is the great robustness of the machine in the case of pressure surges and vibrations, since a closed power flow takes place involving the typically very rigid machine housing, which in turn results in a low noise emission. Due to the complete hydrostatic discharge of the hydraulic forces, the machine according to the invention is also suitable for poorly lubricating media, ie in particular for use in the so-called "water hydraulics".

Preferably, the cylinder star has at least one support region in which the axial width is smaller than in a free-wheeling region which adjoins the support region in the radial direction, wherein at least one control cross-section of the control-plate body is preferably located in the support region. Further preferably, at least one control plate body has a support region corresponding to the support region of the cylinder star and a storage region facing away from the support region in the radial direction outwardly adjoining the support region and / or in the axial direction. In the storage area, the respective control plate body is accommodated in a housing or housing cover, so that the forces introduced by the cylinder star into the control plate body can be dissipated further into the housing or the housing cover.

A particularly robust mechanical construction of the radial piston machine according to the invention is achieved if the support region preferably extends from a central torque coupling region (eg in the form of a multi-tooth bore or a journal) in the radial direction up to a diameter which is approximately 60% to 90%, preferably 70% to 80%, of the maximum diameter of the cylinder star.

A particularly favorable geometry of the control plate body is present if this has a conical, conical-ring-shaped or convex, in particular spherical, curved shape, wherein preferably the support region is designed conical, conical-shaped or convex, in particular spherical, arched. The adjoining in the axial direction storage area, which may have a larger diameter than the support area, then preferably a cylindrical shape, resulting in a particularly simple storage in the housing or the housing cover.

In conical or conical annular control mirror body, the cone angle should be between 90 ° and 150 °, preferably between 1 10 ° and 130 ° and more preferably 120 °, since this is an equiangular triangle of forces with an angle between the radially acting pressure force and the oblique supporting forces of each gives 120 °. The optimum cone angle in each case results from the respective diameters at the beginning and at the end of the conical section and the number of working spaces distributed over the circumference of the cylinder star and can be computationally exact according to the known rules of hydraulics under the premise of a complete hydraulic balance of forces determine.

The invention further ausgestaltend it is proposed that the cylinder star and at least one control mirror body in the axial direction patrizen-matrizen-shaped mesh.

If a respective control mirror body is arranged on both sides of the cylinder star, one of them should be biased in the direction of the opposite control mirror body by means of a spring element supported on a housing or a housing cover, preferably a corrugated spring. This provides axial gap compensation, i. Tightness, in the region of the separation plane between the control mirror body and the cylinder star, in particular in the area of the control cross sections achieved. Regardless of whether the supply or discharge of the hydraulic fluid to or from the cylinder star via only one or two control mirror body, it makes sense in production terms that control channels of two opposing control mirror body and an interposed passageway of the cylinder star are aligned, preferably form a continuous cylindrical bore with a constant cross section. Under the aspect of an always desirable equal part production, the control channels are unused in a control disk body which is not used for hydraulic fluid supply or exhaust, but this is in no way disadvantageous.

Although it is basically possible to provide the pistons on the piston heads with a separate sealing element (piston ring or the like), it is a preferred variant that each piston head of the piston is designed cup-shaped in longitudinal section and with no interposition of a separate sealing element a cup rim sealed to an internal ren shell surface of the respective bore of the cylinder star rests, wherein the pistons are preferably made of plastic and more preferably are plastic injection molded parts. The cup rim has a depth seen in the axial direction of the piston and a thickness seen in the radial direction, which ensures that the fluid pressure in the working space, taking advantage of the component elasticity, ensures sufficient surface pressure between the cup rim outer casing and the bore casing surface. In a production of such pistons as plastic injection molded parts made of a material with sufficient strength, low coefficient of friction in conjunction with the material of the cylinder star and at the same time good elasticity, the pistons according to the invention can be produced very inexpensively. embodiment

The invention will be explained in more detail with reference to two embodiments of a hydrostatic radial piston machine, which is shown in the drawing.

It shows:

A cross section through a first embodiment of a radial piston engine piston with piston rings, as Figure 1, but in longitudinal section,

FIG. 2a is an enlarged view of the cylinder star and the control disk body according to FIG. 2, FIG.

3 shows a cross section through a second embodiment of a radial piston machine with a piston in the shape of a cup, as in FIG. 3, but in longitudinal section and

Fig. 5: as Figure 1, but with illustrated by arrows force vectors

A radial piston machine 1 shown in FIGS. 1, 2 and 2a comprises a housing 2, which-viewed in the axial direction-is closed in a fluid-tight manner on one side with a housing cover 3. In the housing 2, a cam ring 4 is slidably mounted and along each two planar surfaces 5 and 6, which are formed on the one hand on an inner circumferential surface 7 of the housing 2 and on the other hand on an outer circumferential surface 8 of the cam ring.

In addition, the radial piston machine 1 has a rotor in the form of a so-called cylinder star 9, which is rotatable about a rotation axis 10. In the present case, the cylinder star 9 has nine bores 11 arranged equidistantly around its circumference, which, starting from an outer circumferential surface 12 of the cylinder star 9, penetrate radially into its interior, i. on the axis of rotation 10 to extend.

In each bore 1 1, a piston 13 is slidably disposed, each piston 13 has a piston head 14, with which it is sealed in the bore 1 1 mounted, and a plate-shaped piston 15, with the lower end face 16 of the respective piston thirteenth is supported on a spherically curved inner lateral surface 17 of the cam ring 4. Each piston 13 has a from the piston head 14 to the piston 15 extending through bore 18 which opens at the end face 16 of the piston 15 in a pressure chamber 19, which in turn leads to a hydrostatic relief of the bearing of the piston 15 on the lifting ring 4. In known manner, each piston 13 has in the region of its piston head 14 a circumferential groove into which a piston ring 20 is inserted for sealing purposes. Between the piston head 14 and the piston 15 there is a reduced diameter piston neck, which - depending on the position of the piston 13 in the bore 1 1 - allows tilting of the piston longitudinal axis to the bore longitudinal axis. According to the known basic principle of radial piston machines, the axis of rotation 10 of the cylinder star 9 and the center axis of the cam ring 4 (the center axis of the cam ring is not shown in the drawing for reasons of clarity) are arranged eccentrically to each other, wherein the (variable) amount of eccentricity the stroke of Piston 13 defined. During a complete rotation of the cylinder star 9 about the axis of rotation 10, the pistons 13 therefore move from a top dead center, where they are immersed in the deepest hole 1 1, to a bottom dead center, where they together with the walls of the Bore 1 1 limit a maximum work space 22 then. The extent of eccentricity between cylinder star 9 and cam 4 can be varied in the present case with the aid of two hydraulic actuating cylinder, the cylinder bores 23 and 24 are located on opposite sides of the housing 2 and each with an axially displaceable in the cylinder bore 23, 24 mounted cup-shaped piston 25, 26 are provided. Starting from the position shown in Figure 1, in which the eccentricity is maximum leaves the cam 4 (parallel to the flat surfaces 5 and 6) to move the way to the right 27, whereby the eccentricity and thus the delivery rate of the radial piston machine is reduced to zero.

In a manner likewise known from the prior art, the delivery of hydraulic fluid with the aid of the radial piston engine-exemplified by a function as a radial piston pump-takes place in such a way that hydraulic fluid is transferred from an end located in the housing 2 and at its radially inner end 90 ° angled inlet channel 28 flows into a control channel 29 of a control mirror body 30. The control mirror body 30 is located between a housing wall 31 and the cylinder star 9. Another, substantially identical shaped control mirror body 32 is located on the opposite side of the cylinder star 9 and is bounded on its side facing away from the cylinder star 9 by a housing wall 33. In both control mirror bodies 30, 32, the respective control channel 29, 34 in a cylinder star 9 facing end face of the control mirror body 30, 32 extends in a circular segment. This known design makes it possible for the hydraulic fluid to flow into the respective working chamber 22 from the control channel 29 via a respective passageway 35 assigned to each cylinder bore 9 in the suction chamber during an intake phase extending over an angular range of approximately 150 °. As soon as a piston 13 has reached its bottom dead center, the flow connection between the control channel 29 assigned to the inlet channel 28 and the associated passage channel 35 ends, whereas at the next moment a connection exists between the further control channel 37 constructed like the control channel 29 and an outlet channel 36 the "pressure side" of the control mirror body 30 and the radial piston machine 1 is produced. The cross sections of the control channels 29, 37, which are arranged in the respective separation planes between the control mirror body 30 and the cylinder star 9 are referred to as control cross sections 29 ', 37'.

As a result of a continuous rotation of the cylinder star 9 pushes each piston 13 located in the associated working chamber 22 hydraulic fluid through the each bore 1 1 associated passageway 35 and the groove-like expanded and extending over a circular segment of about 150 ° control channel 37 into the outlet channel 36th Between the control cross sections 29 ', 37' of the control mirror body 30 there are two locking surfaces (not visible in the figures) offset by 180 °, which close the passage channels 35 in two intermediate areas between the control cross sections 29 'and 37' by a short circuit between suction and pressure side to prevent. The in Figure 2 Control plate body 32 shown on the right also has a second, ie lower, control channel 38, which in the present case - as well as the upper control channel 34 of this control mirror body 32 - is inoperative.

In order to be able to reliably convey large volume flows from the hydraulic fluid on the suction side of the radial piston machine 1, if necessary, the suction-side control channel 34 of the control plate body 32 can likewise be connected to the inlet channel 28. On the pressure side, the connection of the control channel 38 with the outlet channel 36 is hardly required; For the sake of the same part production, however, both control mirror body 30, 32 are each provided with two control channels 29, 37 and 34, 38. In order to achieve an axial gap compensation in the region of the control plate body 30, 32 and the cylinder star 9, is located between the housing wall 33 and this facing end face of the control mirror body 32 is only schematically illustrated spring element 39 in the form of a rotating wave spring. However, the spring element 39 is not able to apply such large forces in order to compensate for the high hydraulic forces acting in the axial direction. For this purpose, a pressure-compensated compensation surface K is additively provided on the end face of the cover 3 facing the control mirror body 32. This compensation surface K is twice kidney-shaped and corresponds on the one hand with the suction-side control channel 29 and the other with the pressure-side control channel 37. By means of a likewise kidney-shaped sealing element D is a corresponding with the compensation surface K volume between the housing cover 3 and this facing the back End face of the control mirror body 32 sealed. In this way, a pressure-proportional axial contact force is generated, which is always only a few percent above the axial component of the hydraulic splitting force on the respective control mirror body 30, 32. Thus, the gap compensation is ensured without generating large "excess forces", which would only lead to increased friction.

With reference to the enlarged illustration according to FIG. 2a, special features of the control mirror bodies 30, 32 and of the cylinder star 9 will now be explained:

Both Steuerspiegelköper 30, 32 each have a conical-ring-shaped support portion 40, 41 which cooperates with a complementarily shaped, also cone-shaped support portion 42, 43 on the opposite end faces of the cylinder star 9. While the control channels 29, 37 and 34, 38, ie, in particular also the control cross sections 29 ', 37', are located in the support regions 40, 41 of the control plate bodies 30, 32, the control elements extend as through-holes. Passage holes executed passageways 35 in the mutual support areas 42 and 43 of the cylinder star. 9

Both control mirror bodies 30, 32 each have a central through-bore 44, 45 through which runs a drive shaft 46 of the radial piston machine 1. A torque coupling region 47 of the cylinder star 9 is designed as a hexagon socket, in which a correspondingly adapted external hexagon of the drive shaft 46 is inserted in a rotationally fixed manner.

Both control plate bodies 30, 32 have a cylindrical-ring-shaped bearing region 48, 49 adjoining the respective support region 40, 41 in the radial direction, the outer lateral surface 50, 51 of which is respectively mounted in a matched recess in the housing 2 or the housing cover 3 is. The cylinder star 9 has a - viewed in the radial direction - at the support areas 42 and 43 subsequent freewheeling 52, 53, in which between the respective end face 54, 55 of the cylinder star 9 and the opposite end face 56, 57 of the control mirror body 30, 32nd in each case a gap 58, 59 is located.

It can be seen from FIG. 2 a that the width of the cylinder star 9 measured in the axial direction decreases in the support areas 42, 43 towards the axis of rotation 10. The largest axial width 60 is in the freewheeling region 52, 53, whereas the smallest axial width 61 is in the torque coupling region 47. The cone angle of the control plate body 30, 32 is 120 °, so that the track straight of the drawing section plane with the control mirror bodies 30, 32 with the axis of rotation 10 each enclose an angle of 60 °.

Furthermore, it can be seen that the control mirror bodies 30, 32 with their conical-ring-shaped end faces forming the support regions 42, 43 extend beyond the planes formed by the end faces 54, 55 of the cylinder star 9 in the direction of a center plane 62 of the cylinder star perpendicular to the rotation axis 10 9 extend.

The difference between the radial piston machine 1 shown in FIGS. 3 and 4 is that the pistons 13 'have a cup-shaped configuration there in longitudinal section. A in the respective piston head 14 'arranged cup edge 63 has a small, towards the free end of the cup rim 63 toward decreasing wall thickness, so that as a result of a pressure build-up in the working space 22 of the respective bore 1 1 in the cylinder star 9 a self-reinforce- the sealing effect occurs. The pistons 13 'are made as plastic injection molded parts and consist for example of PEEK (poly ether ether ketone) or PAI (poly amide imide).

When the piston 13 'is rotationally symmetric components, wherein the plastic material used elastically in its contact area with the inner circumferential surface of the bore 1 1 allows a change in shape, if due to the inclination of the piston 13' during rotation of the cylinder star 9, the contact line in Area of the piston head 14 'describes an ellipse.

Finally, the various hydraulic vectors occurring during operation of the radial piston machine 1 are also illustrated in the cross-sectional representation according to FIG. 5. The radial hydraulic forces acting in the respective working space 22, illustrated by the arrow P 1, are determined by the symmetrically inclined end faces of the cylinder star 9 or the control mirror body 30,32 hydraulically compensated, which is illustrated by the hydraulic force vectors according to the arrows P2 and P3. In addition, the mechanical forces according to the arrows P4 are still shown in Figure 5, the reaction forces occurring in the housing 2 to the hydraulic forces that are transmitted from the working chamber 22 via the piston 26 and the cam 4. The forces acting on the control mirror bodies 30, 32 in the radial direction are transmitted in their bearing areas 48, 49 to the respective mating surface in the housing 2 or housing cover 3, where the reaction forces are shown in the form of the arrows P5.

LIST OF REFERENCE NUMBERS

1 radial piston machine

2 housings

3 housing cover

4 lifting ring

5 plane surface

6 plane surface

7 inner lateral surface

8 outer surface

9 cylinder star

10 axis of rotation

1 1 hole

12 outer surface

13, 13 'pistons

14, 14 'piston head

15 piston foot

16 face

17 inner lateral surface

18 through hole

19 pressure room

20 piston ring

21 piston neck

22 workspace

23 cylinder bore

24 cylinder bore

25 pistons

26 pistons

27 way

28 inlet channel

29 control channel

29 'control cross section

30 control mirror body

31 housing wall

32 control mirror body

33 housing wall

34 control channel

35 passage channel

36 exhaust duct 37 control channel

37 'control cross section

38 control channel

39 spring element

40 support area

41 support area

42 support area

43 support area

44 through hole

45 through hole

46 drive shaft

47 torque coupling area

48 storage area

49 storage area

50 outer lateral surface

51 outer surface

52 freewheel area

53 freewheel area

54 face

55 face

56 face

57 face

58 gap

59 gap

60 width

61 width

62 median plane

63 cup rim

D sealing element

K compensation area

P1 arrow

P2 arrow

P3 arrow

P4 arrow

P5 arrow

Claims

claims

1. Hydrostatic radial piston machine (1) with a housing

- A about a rotational axis (10) rotatably mounted in the housing (2) cylinder star (9) having a number of holes (1 1), starting from an outer circumferential surface (12) of the cylinder star (9) in its interior extend into and are distributed over the circumference,

- One of the number of holes (1 1) corresponding number of pistons (13, 13 ') which are slidably disposed in the bores (1 1) and each together with the associated bore (1 1) a working space (22) for a Limit hydraulic fluid,

- An eccentrically to the cylinder star (9) arranged cam ring (4) surrounding the cylinder star (9) circumferentially and on the inner lateral surface (8) the cylinder star (9) facing away from the ends of the piston (13, 13 ') during the rotational movement movably supported by the cylinder star (9),

- Two control mirror bodies (30, 32) having a total of at least two control cross sections, of which at least one with the inlet channel (28) and at least one other with the outlet channel (36) in communication, both control mirror bodies (30, 32) each with an end face facing the cylinder star (9) on a center plane (62) of the cylinder star (9) perpendicular to the rotation axis (10) extends beyond a plane which faces from an end face (54, 54) facing the respective control mirror body (30, 32). 55) of the cylinder star (9) is defined in its place with the largest axial width (60),

- One of the number of holes (1 1) of the cylinder star (9) corresponding number of arranged in the latter passage channels (35) - depending on the rotational position of the cylinder star (9) in the cam ring (4) - each having a working space (22) one with the inlet channel (28) corresponding control cross-section or one with the outlet channel (36) corresponding Connect control cross-section or by a on the control mirror body (30, 32) located closure surface are closable characterized in that each control mirror body (30, 32) has a bearing region (48, 49), in the radially acting forces on a respective mating surface in the housing ( 2) or a housing cover (3) mounted therein are transferable.

2. Radial-piston machine according to claim 1, characterized in that the cylinder star (9) has at least one support region (42, 43), in which the axial width is smaller than in a radial direction to the support region (42, 43) to the outside at least one control cross-section of the control plate body (30, 32) is preferably located, wherein more preferably at least one control plate body (30, 32) one with the support region (42, 43) of the cylinder star (9) corresponding support region (40, 41), preferably either in the radial direction outwardly to the support region (40, 41) subsequent and / or in axial, the support region (40, 41) facing away from the respective direction Storage area (48, 49) connects.

3. Radial piston machine according to claim 2, characterized in that the support region (42, 43) of the cylinder star (9) preferably extends from a central torque coupling region (47) in the radial direction up to a diameter of about 60% to 90%, preferably 70% to 80% of the maximum diameter of the cylinder star (9).

4. Radial piston machine according to one of claims 1 to 3, characterized in that the control mirror body (30, 32) has a conical, conical or convex, in particular spherical, curved shape, wherein preferably the support portion (40, 41) conical, conical or convex , in particular spherical, arched.

5. Radial piston machine according to claim 4, characterized in that the cone angle between 90 ° and 150 °, preferably between 1 10 ° and 130 °.

6. Radial piston machine according to one of claims 1 to 5, characterized in that the cylinder star (9) and at least one control mirror body (30, 32) in the axial direction patrizen-matrizen-shaped mesh.

7. Radial piston machine according to one of claims 1 to 6, characterized in that the two control mirror body (30, 32) in the axial direction relative to each other are displaceable, preferably that one of the control mirror body (32) in the axial direction relative to the housing (2) or the housing cover (3) is displaceable, whereas the other control mirror body (30) in the axial direction in the housing

(2) or the housing cover (3) is fixed.

8. Radial-piston machine according to one of claims 1 to 7, characterized in that on both sides of the cylinder star (9) each have a control mirror body (30, 32) is arranged, wherein a control mirror body (32) by means of a on the housing (2) or the housing cover (3) supporting the spring element (39), preferably a corrugated spring, in the direction of the opposite control mirror body (30) is biased.

9. Radial-piston machine according to one of claims 1 to 8, characterized in that in each case with a working space (22) corresponding passage channels (35) of the cylinder star (9) each from a support region to the opposite

Supporting region (42, 43) extend.

10. Radial-piston machine according to one of claims 1 to 9, characterized in that control channels (29, 34, 37, 38) of two opposing control mirror body (30, 32) and an interposed passageway (35) of the cylinder star (9) are aligned, preferably form a continuous cylindrical bore with a constant cross-section.

1 1. A radial piston machine according to one of claims 1 to 10, characterized in that in each case a piston head (14 ') of the piston (13') is cup-shaped in longitudinal section and without interposition of a separate sealing element with a cup rim (63) sealingly on an inner Mantle surface of the respective bore (1 1) of the cylinder star (9) is applied, wherein the piston (13 ') are preferably made of plastic and more preferably are plastic injection molded parts.