Radial piston compressor

Abstract

The invention relates to a radial piston compressor with several cylinders (13) arranged radially to a drive shaft (10), each cylinder containing a piston (16), the drive shaft (10) carrying at least one cam disk (18) against which the pistons (16) bear such that the pistons (16) alternately perform a reciprocating motion in the cylinders (13) through rotation of the drive shaft (10), and wherein two cylinders (13) are arranged diametrically opposite each other, forming a cylinder pair (11, 12) whose pistons (16) are rigidly connected to one another. The invention further relates to a motor vehicle with such a radial piston compressor.

Description

[0001] The invention relates to a radial piston compressor and a motor vehicle with such a radial piston compressor.

[0002] In motor vehicles, various compressors are used, particularly for air conditioning, to compress a refrigerant and thus achieve the desired climate control in the vehicle interior. Different compressor technologies are employed. Scroll compressors and axial piston compressors are widely used, for example. Radial piston compressors are also possible.

[0003] Conventional radial piston compressors consist of radially oriented cylinders in which pistons perform a reciprocating motion. To control the flow of refrigerant into the respective cylinders, corresponding inlet valves are provided. However, these require complex controls and also increase the size of the radial piston compressor. Furthermore, conventional radial piston compressors generate undesirable torques that lead to vibrations and, in particular, undesirable noise. The occurrence of these additional torques, as well as the use of inlet valves, limits the rotational speed of conventional radial piston compressors. Consequently, a comparatively large displacement is required to achieve the desired compressor output. This, in turn, increases the size of conventional radial piston compressors.

[0004] Against this background, the object of the invention is to provide a radial piston compressor characterized by a compact design and smooth operation. Furthermore, the object of the invention is to provide a motor vehicle equipped with such a radial piston compressor.

[0005] According to the invention, this problem is solved by the radial piston compressor according to claim 1 and the motor vehicle according to claim 16.

[0006] The invention is based on the concept of a radial piston compressor with several cylinders arranged radially to a drive shaft, each containing a piston. The drive shaft carries at least one cam disk against which the pistons rest, such that the pistons alternately perform a reciprocating motion within the cylinders as the drive shaft rotates. Two cylinders are arranged diametrically opposite each other, forming a cylinder pair. The pistons of each cylinder pair are rigidly connected to one another.

[0007] The rigid connection of the pistons in a cylinder pair results in positive piston control via the cam disc. This means that the pistons are guided by the cam disc in both their compression and intake movements. The cam disc, in combination with the rigidly connected pistons, thus forms a desmodromic drive. This eliminates the need for an additional piston return mechanism. Consequently, the radial piston compressor according to the invention is particularly compact and simple in design.

[0008] Furthermore, by grouping the cylinders into cylinder pairs, the radial piston compressor according to the invention achieves high efficiency. In particular, at least four pistons can be guided by positive control, so that the displacement of the individual pistons can be made comparatively small without impairing the overall efficiency. This also contributes to a compact and simple design.

[0009] The positive control of the pistons of each cylinder pair provided in the radial piston compressor according to the invention also enables the radial piston compressor to operate at relatively high speeds. This further contributes to high efficiency and, at the same time, to a compact design.

[0010] In a preferred embodiment of the radial piston compressor according to the invention, two pairs of cylinders are arranged at right angles to each other. Each pair of cylinders comprises two pistons that are rigidly connected to one another. The pistons of each cylinder pair can alternately perform a stroke movement. This means that one piston of a cylinder pair performs a compression movement, while simultaneously another piston of the cylinder pair performs a suction movement. The arrangement of two cylinder pairs at right angles to each other results in particularly smooth running. In particular, this avoids additional torque, which prevents vibrations and thus also results in low noise levels. The radial compressor is exceptionally smooth and quiet and can also be operated at high speeds while maintaining low noise emissions.

[0011] In the radial piston compressor according to the invention, the pistons of a cylinder pair can be connected to each other via a bridge that includes an elongated hole through which the drive shaft extends. This design further contributes to the compactness of the radial piston compressor. The elongated hole preferably has a length that corresponds at least to the stroke of the respective pistons. This allows the pistons to move between their dead centers without being blocked by the drive shaft. The bridge connects the two pistons in such a way that, when the drive shaft rotates, one of the pistons performs a compression movement and a diametrically opposite piston performs a suction movement. The bridge can be formed integrally with the two diametrically opposite pistons, i.e., monolithically.

[0012] Preferably, the web surrounds the cam disk such that the cam disk is arranged in a common cylinder plane with at least the pistons of a cylinder pair, and in particular with all pistons of the radial piston compressor. Essentially, the web can therefore be arranged in a plane offset from the cylinder plane. In this respect, the web can connect the two diametrically opposed pistons, similar to a bridge. This does not preclude the web from being formed integrally or monolithically with the two diametrically opposed pistons.

[0013] The cylinders and pistons can each have a rectangular cross-sectional profile. Such a cross-sectional profile further contributes to the compact design of the radial piston compressor. In particular, this allows the axial length of the radial piston compressor to be reduced. For the purposes of this application, axial length refers to the length of the radial piston compressor along the axis of rotation of the drive shaft.

[0014] In a further preferred embodiment of the radial piston compressor according to the invention, the cylinders are arranged in a cylinder housing comprising a lower part and an upper part. The cylinder housing can be arranged in a compressor housing and sealed against a cylindrical inner wall of the compressor housing.

[0015] The lower part can have radially oriented channels, each forming three cylinder inner walls. The upper part can be formed by at least one cover plate, which forms a fourth cylinder inner wall. In cylinders with a preferably rectangular cross-sectional profile, four cylinder inner walls are therefore provided, oriented perpendicular to one another. Three of these cylinder inner walls can be formed by the lower part of the cylinder housing, specifically by the channels arranged therein. The fourth cylinder inner wall can be formed by the cover plate, which is associated with the upper part of the cylinder housing. The use of a lower part with channels and a cover plate as the upper part simplifies the design of the radial piston compressor. In particular, this reduces the number of components, contributing to a cost-effective and robust design.

[0016] Another advantage of the cylinder housing with a lower and an upper part is the ease of component manufacturing. Essentially, the cylinder housing forms a sandwich-like structure of two elements: the lower and the upper part. These parts are extremely easy to manufacture due to their relatively simple geometric shapes. Thus, the cylinder housing, or rather the lower and upper parts, can be easily produced by machining processes such as grinding and hardened to achieve the desired component strength.

[0017] In a special variant, the lower part can have two aligned channels on opposite sides, and the upper part can have four crescent-shaped cover plates, each covering one channel to form a cylinder. It is also possible for the lower part to have two aligned channels on a common side, with the upper part then having a single annular cover plate that covers all the channels to form the cylinders.

[0018] With regard to the compact design of the radial piston compressor, it is particularly advantageous if all pistons bear against the outer contour of a common cam disk. In this way, all pistons and the common cam disk are arranged in a single plane, which significantly limits the axial length of the radial piston compressor.

[0019] The cam disc can have a circular outer contour. With this design, it is advantageous for the cam disc to be eccentrically connected to the drive shaft. The cam disc can generally be formed as a single piece with the drive shaft or monolithically. Alternatively, the cam disc can be pressed onto the drive shaft or otherwise rigidly connected to it. The rigid connection between the cam disc and the drive shaft is, in particular, rotationally fixed.

[0020] Alternatively, the cam disc can be designed with a non-circular outer contour. This non-circular contour can be shaped to induce different piston strokes in the cylinder pairs. For example, this allows for multi-stage compression to be achieved with a single radial piston compressor.

[0021] Another preferred embodiment of the invention provides that the cylinder pairs, in particular all cylinders, are arranged in a common cylinder plane extending perpendicular to the drive shaft. The arrangement of all cylinders in a common plane, in particular the cylinder plane, reliably ensures a particularly compact design of the radial piston compressor, especially with regard to its overall length along the axis of rotation of the drive shaft.

[0022] Alternatively, it is also conceivable that the cylinder pairs are arranged in different, particularly parallel, cylinder planes, each extending perpendicular to the drive shaft. This can be advantageous, for example, if the displacement volume of individual cylinders is to be increased without compromising the stability of the component walls separating the individual cylinders.

[0023] In a preferred embodiment of the radial piston compressor according to the invention, each cylinder has at least one inlet opening, with inlet valve slides provided in an inlet plane offset from the cylinder plane. The inlet valve slides preferably bear against a further cam disk, so that they at least temporarily close and / or open the inlet openings through the rotation of the drive shaft. The inlet valve slides can be rigidly connected to each other in pairs, analogous to the pistons. This results in positive control of the inlet valve slides during rotation of the drive shaft. Therefore, conventional inlet valves can be dispensed with. This reduces the complexity of the radial compressor and, in addition, allows for higher rotational speeds to be used to operate the radial piston compressor due to the elimination of inlet valves. This increases the efficiency of the radial piston compressor.

[0024] Each cylinder can have at least one outlet port, to which a reed valve is assigned that closes and / or opens the outlet port, at least temporarily. Using a reed valve offers several advantages. Firstly, a reed valve reacts very quickly and can therefore reliably control the outlet of compressed refrigerant even at high speeds of the radial piston compressor. Secondly, a reed valve has a particularly simple design and is therefore cost-effective. Furthermore, a reed valve is compact, which means the overall size of the radial piston compressor is hardly affected.

[0025] Preferably, the inlet and outlet openings are formed in opposing, particularly parallel, cylinder inner walls. This allows for improved control of the refrigerant inlet and outlet timing.

[0026] In preferred embodiments of the radial piston compressor according to the invention, the drive shaft is non-rotatably connected to the rotor of an electric motor. The radial piston compressor can therefore be driven purely electrically. This is particularly advantageous when using the radial piston compressor in automotive engineering, for example in battery-electric vehicles.

[0027] In general, the radial piston compressor described here is particularly well-suited for use in motor vehicles, and especially in air conditioning systems for vehicle interiors. It is particularly advantageous to use carbon dioxide, especially R744, as the refrigerant in such an air conditioning circuit. The radial piston compressor described here is therefore ideally suited for compressing carbon dioxide.

[0028] In particular, a secondary aspect of the invention relates to a motor vehicle with a previously described radial piston compressor. The motor vehicle can, in particular, be a multi-track passenger car. Use in multi-track battery-electric vehicles is especially preferred. However, it is also advantageous to use the radial piston compressor described herein in hybrid-electric vehicles that have both an internal combustion engine and an electric motor as drive motors.

[0029] The invention is explained in more detail below using an exemplary embodiment with reference to the accompanying schematic drawings. These show Fig. 1 a cross-sectional view through a radial piston compressor according to the invention in a preferred embodiment; Fig. 2 a perspective view of a drive shaft with a cylinder housing of the radial piston compressor according to Fig. 1; Fig. 3 another perspective view of the assembly according to Fig. 2; Fig. 4 a longitudinal section view through the assembly according to Fig. 2; Fig. 5 a cross-sectional view through the assembly according to Fig. 2 in a cylindrical plane; Fig. 6 a cross-sectional view through the assembly according to Fig. 2 in one inlet level; and Fig. 7 a perspective view of the drive shaft with one cam disc and another cam disc, the drive shaft being part of the radial piston compressor according to Fig. 1 is.

[0030] In the cross-sectional view according to Fig. Figure 1 shows a radial piston compressor according to the invention in its entirety. The radial piston compressor essentially comprises a compressor housing 31, which may be made up of multiple parts. Furthermore, an electronics housing 32 is provided, which contains the control electronics of the radial piston compressor. The multi-part compressor housing 31 includes a drive section in which an electric motor 30 is arranged. The electric motor 30 drives a drive shaft 10 which is non-rotatably connected to the rotor of the electric motor 30.

[0031] The drive shaft 10 extends into a compressor section of the compressor housing 31. The compressor section can be formed by a further housing component that is rigidly connected to the drive section. The compression of the refrigerant flowing into the radial piston compressor essentially takes place in the compressor section. A high-pressure section with a high-pressure chamber 33 follows the compressor section, into which the compressed refrigerant flows and is then discharged into a refrigerant circuit.

[0032] The drive shaft is supported in the compressor housing 31 via shaft bearings 34. The shaft bearings 34 are preferably located in the compressor section.

[0033] The drive shaft 10 further comprises two cam discs 18, 19. In particular, one cam disc 18 and another cam disc 19 are provided. The cam discs 18, 19 are preferably formed integrally with the drive shaft 10. The cam disc 18 acts on pistons 16, which are guided in cylinders 13 extending radially from the axis of rotation of the drive shaft 10. Two diametrically opposed cylinders 13 form a cylinder pair 11, 12. In the longitudinal section view according to Fig. 1 a first pair of cylinders 11 is recognizable.

[0034] The pistons 16 guided in the cylinders 13 also form piston pairs 14, 15, as shown in the longitudinal section view according to Fig. Figure 1 shows a first pair of pistons 14. The pistons 16 of the first pair of pistons 14 are preferably rigidly connected to each other. In particular, the connection is preferably made via a web 17, as shown in the longitudinal section view. Fig. 1 The web 17 of the second piston pair 15 is visible in cross-section. The web 17 is perforated by an elongated hole 20 through which the drive shaft 10 extends.

[0035] As in Fig. As can be seen in Figure 1, the cam disk 18 is eccentrically aligned with the drive shaft 10. This causes the first pair of pistons 14 to move alternately in a radial stroke motion relative to the drive shaft 10. Rotation of the drive shaft 10 thus results in a radial stroke motion of the pistons 16. The pistons 16 perform a suction motion when they move radially inwards towards the axis of rotation of the drive shaft 10. When moving radially outwards away from the axis of rotation of the drive shaft 10, the refrigerant flowing into the cylinders 13 is compressed. The compressed refrigerant can flow into the high-pressure chamber 33 via outlet openings 28. The outlet openings 28 are each closed by reed valves 29, which open when a predetermined pressure is reached within the cylinders 13, allowing the compressed refrigerant to escape into the high-pressure chamber 33.

[0036] The cylinders 13 each have inlet openings 26, which are in Fig. 1 are not recognizable. Fig. Figure 2 shows the arrangement and position of the inlet openings 26. Specifically, the inlet openings 26 are arranged in a lower part 22 of a cylinder housing 21. Inlet valve slides 27 are provided to open and close the inlet openings 26. Two inlet valve slides 27 are also rigidly connected to each other via a web 17, thus forming an inlet valve slide pair. The web 17 of the inlet valve slides 27 also has an elongated hole 20 through which the drive shaft 10 extends. The inlet valve slides 27 contact the outer contour of the further cam disk 19, so that the inlet valve slides can be converted into a radial stroke movement due to the rotation of the drive shaft 10. The operating principle of the inlet valve slides 27 essentially corresponds to the operating principle of the pistons 16 or the piston pairs 14, 15.

[0037] The rotation of the drive shaft 10 therefore not only moves the pistons 16 radially, but also the inlet valve slides 27. The inlet valve slides 27 thus alternately open or cover the inlet openings 26, so that an inflow of refrigerant into the cylinders 13 is enabled and / or blocked.

[0038] The cam discs 18, 19 positively control the pistons 16 and the intake valve slides 27. Since two intake valve slides 27 and two pistons 16 are rigidly connected, the rotation of the drive shaft 10 causes not only a radial outward movement but also a radial inward movement, so that neither the intake valve slides 27 nor the pistons 16 require any other return mechanisms. Rather, the entire movement of the pistons 16 and the intake valve slides 27 is positively guided by the cam discs 18, 19 of the drive shaft 10.

[0039] The exhaust openings 28 are arranged in an upper part 24 of the cylinder housing 21. The upper part 24 is specifically formed by a cover plate 25. The exhaust openings 28 can extend obliquely through the cover plate 25, as shown in Fig. 1 is recognizable.

[0040] Fig. Figure 2 shows the drive shaft 10 and the cylinder housing 21 as a single assembly. The cylinder housing 21 comprises the lower part 22 and the upper part 24. The upper part 24 is formed by the cover plate 25. The reed valves 29 are arranged in the cover plate 25. Preferably, the reed valves 29 are screwed to the cover plate 25. Each reed valve 29 covers an outlet port 28 of a cylinder 13.

[0041] The cover plate 25 has a central through-opening through which in Fig. 2 the cam disk 18 is visible. The cam disk 18 acts on the pistons 16 of the piston pairs 14, 15. Preferably, two piston pairs 14, 15 are provided, which are aligned at right angles to each other. In particular, two cylinder pairs 11, 12 are provided, which are aligned at right angles to each other and guide a total of four pistons 16. In this way, the radial piston compressor forms a four-cylinder compressor.

[0042] The cylinder housing 21, formed by the lower part 22 and the upper part 24, encloses the cylinders 13. Each cylinder 13 preferably has a rectangular cross-section. The cylinder inner walls are formed partly by the lower part 22 and partly by the upper part 24 or the cover plate 25. Preferably, a total of four channels are formed in the lower part 22, each having a bottom and two parallel side walls. The bottom and the side walls together form three cylinder inner walls of the respective cylinders 13. The cover plate 25 covers the channels 22 and thus forms the fourth cylinder inner wall of the respective cylinders 13.

[0043] The perspective view according to Fig. Figure 3 essentially shows an underside of the cylinder housing 21. In particular, an underside of the lower part 22 is visible, on which several sealing plates 35 are arranged. The sealing plates 35 are screwed in place. A total of four sealing plates 35 are provided. Alternatively, it is possible that a single sealing plate 35 is provided, which closes the entire underside of the lower part 22. Specifically, the sealing plates 25 cover channels in which the intake valve slides 27 are guided. The intake valve slides 27 slide on the outer contour of the further camshaft 19, which is located in Fig. 3 is also evident. It is also evident that two intake valve slides 27 are connected to each other via a bridge 17, the bridge 17 having an elongated hole through which the drive shaft 10 extends. The movement of the further cam disk 19 thus positively guides the intake valve slides radially, thereby alternately opening the intake ports 26. The outer contour of the further camshaft 19 is preferably matched to the outer contour of the camshaft 18 such that the intake ports 26 are opened or closed by the intake valve slides 27 in accordance with the movement of the pistons 16.

[0044] Fig. Figure 4 shows a longitudinal section view through the assembly according to Fig. 2. It is clearly evident that the drive shaft 10 and the cam discs 18, 19 are formed in one piece, i.e., monolithically. It is apparent that the cam discs 18, 19 have a non-circular outer contour. The pistons 16 of the first pair of pistons 14 slide on the cam disc 18, while the intake valve slides 17 slide on the other cam disc 19. The web 17 of the intake valve slides 27, which rigidly connects each pair of intake valve slides 27, is also clearly visible. The web 17 is arranged in a plane that is parallel and offset from the plane of the intake valve slides 27. This plane of the intake valve slides 27 is also referred to as the intake plane.

[0045] The pistons 16, on the other hand, are located in a cylinder plane in which preferably all cylinders 13 of the radial piston compressor are located. The cylinders 13 are therefore arranged in a common or uniform cylinder plane. Two pistons 16 are rigidly connected to each other via a web 17, as shown in the longitudinal section view. Fig. Only the web 17, which connects the pistons 13 of the second piston pair 15, is visible in section 4. The web 17 is shown in cross-section. The web 17, which connects the pistons 16 of the first piston pair 14, is positioned outside the longitudinal section and is therefore not readily apparent.

[0046] Fig. Figure 4, in its longitudinal section, clearly shows the lamellar valves 29 that close the exhaust ports 28. The exhaust ports 28 are located essentially in a radially outer section of the respective cylinder 13.

[0047] The cross-sectional view according to Fig. Figure 5 illustrates the arrangement and function of the cylinder-piston assembly in the radial piston compressor. A total of four pistons 16 are provided, guided in four cylinders 13. The cylinders 13 are radially aligned to a center defined by the axis of rotation of the drive shaft 10. Two pistons 16 form a piston pair 14, 15. A first piston pair 14 is guided in a first cylinder pair 11. A second piston pair is guided in a second cylinder pair 12. The cylinders 13 of each cylinder pair 11, 12 are arranged diametrically opposite each other.

[0048] The drive shaft 10 carries the cam disk 18, which is in contact with the piston 16. Specifically, the cam disk 18 contacts all pistons 16 simultaneously. Rotation of the drive shaft 10 causes the cam disk 18 to move along a path that results in the pistons 16 moving radially within their cylinders 13. Two pistons 16 are rigidly coupled to each other via a bridge 17. This rigid coupling ensures that the outward movement of one piston 16 necessarily results in an inward movement of the opposite piston 16 of the same pair 14, 15.

[0049] When the piston 16 moves outwards, the refrigerant is compressed until a predetermined pressure is reached. Once this pressure is reached, the corresponding reed valve 29 opens, allowing the compressed refrigerant to escape through the outlet opening 28 into the high-pressure chamber 33. During the subsequent inward movement of the piston 16, the cylinder 13 is preferably filled with uncompressed refrigerant through the inlet opening 26. For this purpose, the inlet valve slides 27, which are positively actuated by the cam disk 19, open the corresponding inlet opening 26.

[0050] Fig. Figure 5 also illustrates that the drive via the drive shaft 10 is essentially a desmodromic drive, whereby every movement of the pistons is positively controlled. A return mechanism is therefore not necessary.

[0051] Fig. Figure 6 shows the operating principle for controlling the intake valve slides 27 in a cross-sectional view. Preferably, two intake ports 26 open into each cylinder 13, which can be opened and closed by means of the intake valve slides 27. This occurs analogously to the movement of the pistons 16, by means of a further cam disk 19, which imparts a linear motion to four intake valve slides 27, originating radially from the axis of rotation of the drive shaft 10. Two intake valve slides 27 are rigidly coupled to each other via a web 17. The web 17 has an elongated hole through which the drive shaft 10 extends. Consequently, rotation of the drive shaft 10 causes a rotational movement of the further cam disk 19, on whose outer contour the intake valve slides 27 slide, thus alternately opening or closing the intake ports 26.

[0052] Fig. Figure 7 shows again in a perspective view the construction of the drive shaft 10 with the two cam discs 18 and 19. The cam disc 18, which acts on the pistons 16, is thicker than the other cam disc 19, which acts on the intake valve slides 27. The greater thickness of cam disc 18 is chosen because higher forces act on the pistons 16 during compression, which are absorbed by the drive shaft. It is also evident that the shape of the cam discs 18 and 19 is coordinated, thereby controlling the refrigerant inlet into the cylinders 13 according to the piston position.

[0053] The radial piston compressor described here is preferably suitable for operation at drive shaft speeds 10 between 200 and 7500 revolutions per minute. The inlet valve slides 27 allow for particularly high speeds, resulting in high compression efficiency. The individual components can preferably be sealed with oil.

[0054] As can be seen in the drawings shown here, the radial piston compressor has a particularly simple design. In particular, the in Fig. The assembly shown in Figure 3, comprising the cylinder housing 21, is essentially designed in a sandwich-like or plate-like structure, which enables particularly simple component manufacturing. This makes the radial piston compressor not only compact but also cost-effective to produce. Reference symbol list 10 Drive shaft 11 first pair of cylinders 12 second cylinder pair 13 cylinders 14 first pair of pistons 15 second pair of pistons 16 pistons 17 Bridge 18 Cam disc 19 more cam discs 20 elongated holes 21 cylinder housings 22 Lower part Channel 23 24 Top 25 Cover plate 26 Entrance opening 27 Inlet valve slides 28 Outlet opening 29 lamellar valve 30 electric motor 31 Compressor housing 32 electronic enclosures 33 High-pressure chamber 34 shaft bearings 35 Closure plate

Claims

[1] Radial piston compressor with several cylinders (13) arranged radially to a drive shaft (10), in each of which a piston (16) is guided, wherein the drive shaft (10) carries at least one cam disk (18) against which the pistons (16) bear such that the pistons (16) alternately perform a stroke movement in the cylinders (13) by a rotation of the drive shaft (10), and wherein two cylinders (13) are arranged diametrically opposite each other and form a cylinder pair (11, 12) whose pistons (16) are rigidly connected to each other. [2] Radial piston compressor according to claim 1 characterized by , that two pairs of cylinders (11, 12) arranged at right angles to each other are provided. [3] Radial piston compressor according to claim 1 or 2 characterized by , that the pistons (16) of a pair of cylinders (11, 12) are connected to each other via a bridge (17) which includes an elongated hole (20) through which the drive shaft (10) extends. [4] Radial piston compressor according to claim 3 characterized by , that the bridge (17) encompasses the cam disk (18) in such a way that the cam disk (18) is arranged in a common cylinder plane at least with the pistons (16) of a pair of cylinders (11, 12), in particular with all pistons (16) of the radial piston compressor. [5] Radial piston compressor according to one of the preceding claims characterized by , that the cylinders (13) and the pistons (16) each have a rectangular cross-sectional profile. [6] Radial piston compressor according to one of the preceding claims characterized by , that the cylinders (13) are arranged in a cylinder housing (21) which has a lower part (22) and an upper part (24), wherein the lower part (22) has radially oriented channels (13) which each form three cylinder inner walls, and the upper part (24) is formed by at least one cover plate (25) which forms a fourth cylinder inner wall. [7] Radial piston compressor according to one of the preceding claims characterized by , that all pistons (16) bear against the outer contour of a common cam disk (18). [8] Radial piston compressor according to one of the preceding claims characterized by , that the cam disk (18, 19) has a circular outer contour. [9] Radial piston compressor according to any one of claims 1 to 7 characterized by , that the cam disk (18, 19) has a non-circular outer contour. [10] Radial piston compressor according to one of the preceding claims characterized by , that the cylinder pairs (11, 12), in particular all cylinders (13), are arranged in a common cylinder plane which extends perpendicular to the drive shaft (10). [11] Radial piston compressor according to any one of claims 1 to 9 characterized by, that the cylinder pairs (11, 12) are arranged in different, in particular parallel, cylinder planes, each extending perpendicular to the drive shaft (10). [12] Radial piston compressor according to claim 10 or 11 characterized by , that the cylinders (13) each have at least one inlet opening (26), wherein inlet valve slides (27) are provided in an inlet plane offset to the cylinder plane, which bear against a further cam disk (19) in such a way that they close and / or open the inlet openings (26) at least temporarily by the rotation of the drive shaft (10). [13] Radial piston compressor according to one of the preceding claims characterized by , that the cylinders (13) each have at least one exhaust port (28) to which a lamellar valve (29) is assigned, which closes and / or releases the exhaust port (28) at least temporarily. [14] Radial piston compressor according to claim 13 characterized by, that the inlet openings (26) and the outlet openings (28) are each formed in opposite, in particular parallel, cylinder inner walls. [15] Radial piston compressor according to one of the preceding claims characterized by , that the drive shaft (10) is connected to a rotor of an electric motor (30) in a rotationally fixed manner. [16] Motor vehicle with a radial piston compressor according to one of the preceding claims.

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