EP2886862B1 - Compressor - Google Patents

Description

Technical area

The present invention is concerned with a compressor, in particular a compressor with a reciprocating compressor.

Background of the invention

Mobile compressors are used, for example, on construction sites or for manual activities in which compressed air is required for connected compressed air tools. A frequently used type of compressor is the piston compressor, in which air is sucked into one or more cylinders, compressed by a piston and expelled again as compressed air. The amount of air delivered by piston compressors is usually adapted to the respective compressed air requirement by regulating the drive speed of the machine driving the compressor. In the pamphlet DE 10 2004 007 882 B4 For example, a compressor with a compressed air sensor is shown, depending on the measured value of which the speed control of a reciprocating compressor runs.

Due to their cyclical operation, piston compressors do not have a continuous output of compressed air, but generate compressed air in pulses. Therefore, a certain compressed air buffer volume is usually kept in order to dampen the compressed air pulses through the compressor. This buffer volume is conventionally kept in separate storage containers so that compressed air can be made available to a compressed air consumer connected to the storage container at a uniformly high pressure. The pamphlet DE 10 2009 052 510 A1 for example deals with a speed-controlled piston compressor, which has a light and compact compressed air tank made of plastic.

There are various other approaches for the design of compressed air tanks for reciprocating compressors: For example, the publication shows U.S. 6,089,835 A a reciprocating compressor with a compressed air tank, which is formed by a shell housing placed on the outside of the motor housing. The Pamphlet U.S. 5,370,504 A shows a piston compressor in which the compressor cylinders are completely embedded in a storage tank for compressed air. The pamphlet WO 2007/041818 A1 discloses a centrifugal compressor having a compression chamber, a drive motor and a compression rotor on a shaft driven by the drive motor. The radial compressor comprises a housing, in the outer wall of which a compressed air storage tank is arranged.

There is, however, a need for solutions for compressors that are lighter in weight and smaller in size so that they are more suitable for transport by hand.

Summary of the invention

Therefore, according to one aspect of the invention, a reciprocating compressor is provided with a motor, a drive shaft connected to the motor and driven by it, a crank drive connected to the drive shaft, at least one compressed air generating device with a piston movable in a cylinder, which is driven by the crank drive , and which is designed to generate compressed air in a compression chamber of the cylinder, a crankcase, which has an inner chamber wall in the form of a hollow body which at least partially accommodates the drive shaft, an outer chamber wall spaced radially from the drive shaft from the inner chamber wall, an end wall, and has a partition wall, and a compressed air storage container which is designed to receive compressed air generated by the compressed air generating device, wherein the compressed air storage container through the inner chamber wall, the outer chamber wall, the end wall and the partition and is formed.

A basic idea of the invention consists in embedding the storage container for compressed air generated by the compressor in the crankcase of the compressor by using the space around the drive shaft. This results in a great advantage in that a separate storage container can be dispensed with, which in turn contributes to considerable weight and cost savings. The entire structure of the compressor becomes more compact, so that the compressor remains handy and portable despite the large storage volume.

In addition, by integrating the compressed air storage tank into the crankcase, the necessary number of components can be reduced, which in turn reduces the assembly effort for the compressor. The fact that the drive shaft is supported in a one-piece crankcase section also eliminates the need for complex adjustment of the individual bearings. Furthermore can According to a further embodiment of the compressor according to the invention, the compressor can furthermore have at least one longitudinal rib which is formed in one piece with the crankcase on the outside of the compressed air storage tank.

According to a further embodiment of the compressor according to the invention, the compressor can furthermore have a motor support, which accommodates and holds the motor, the crankcase being formed around the motor at a distance from the motor support, and the compressed air storage tank at least partially surrounding the motor between the crankcase and the motor support extends around.

According to a further embodiment of the compressor according to the invention, the compressed air storage container can enclose the drive shaft in an angular range of 360 °.

According to a further embodiment of the compressor according to the invention, the ratio of the distance between the axis of rotation of the drive shaft up to the point on the inner wall of the compressed air storage container that is most vertically spaced from the drive shaft to the distance between the axis of rotation of the drive shaft and the top dead center of a piston of the compressed air generating device can be between 0.2 and 1 .

According to a further embodiment of the compressor according to the invention, the ratio of the distance between the axis of rotation of the drive shaft to the point on the inner wall of the compressed air storage container that is most vertically spaced from the drive shaft to the maximum axial extension of the compressed air storage container 25 can be between 0.3 and 2.5.

According to a further embodiment of the compressor according to the invention, the compressed air generating device can have at least one compression chamber, and the volume ratio between the volume of the compressed air storage container and the sum of the geometric stroke volumes of the compressor chambers of the compressed air generating device can be between 5 and 25.

Brief summary of the drawings

The invention will be described in more detail below in connection and with reference to the exemplary embodiments as in the accompanying drawings.

Fig. 1

zeigt eine schematische Darstellung eines Kompressors in Schnittansicht gemäß einer Ausführungsform der Erfindung.

Fig. 2

zeigt eine schematische Illustration eines Querschnitts durch den Kompressor in Fig. 1.

Fig. 3

zeigt eine detaillierte Illustration des Kompressors in Fig. 1 gemäß einer weiteren Ausführungsform der Erfindung.

Fig. 4

zeigt eine schematische Darstellung eines Kompressors in Schnittansicht mit gemäß einer weiteren Ausführungsform der Erfindung.

Fig. 5

zeigt eine detaillierte Illustration des Kompressors in Fig. 4 gemäß einer weiteren Ausführungsform der Erfindung.

Fig. 6

zeigt eine schematische Darstellung eines Kompressors in Schnittansicht gemäß einer weiteren Ausführungsform der Erfindung.

Fig. 7

zeigt eine schematische Darstellung eines Kompressors in Schnittansicht gemäß einer weiteren Ausführungsform der Erfindung.

Fig. 8

zeigt eine schematische Darstellung eines Kompressors in Schnittansicht gemäß einer weiteren Ausführungsform der Erfindung.

The accompanying drawings serve for a better understanding of the present invention and illustrate exemplary embodiments of the invention. They serve to explain principles, advantages, technical effects and possible variations. Of course, other embodiments and many of the intended advantages of the invention are also conceivable, especially in view of the detailed description of the invention presented below. The elements in the drawings are not necessarily shown true to scale and, for the sake of clarity, are in some cases shown in a simplified or schematic manner. The same reference symbols denote the same or similar components or elements.

Fig. 1

shows a schematic representation of a compressor in sectional view according to an embodiment of the invention.

Fig. 2

FIG. 13 shows a schematic illustration of a cross section through the compressor in FIG Fig. 1 .

Fig. 3

shows a detailed illustration of the compressor in FIG Fig. 1 according to a further embodiment of the invention.

Fig. 4

shows a schematic representation of a compressor in sectional view according to a further embodiment of the invention.

Fig. 5

shows a detailed illustration of the compressor in FIG Fig. 4 according to a further embodiment of the invention.

Fig. 6

shows a schematic representation of a compressor in sectional view according to a further embodiment of the invention.

Fig. 7

shows a schematic representation of a compressor in sectional view according to a further embodiment of the invention.

Fig. 8

shows a schematic representation of a compressor in sectional view according to a further embodiment of the invention.

Although specific embodiments are described and illustrated herein, it is clear to a person skilled in the art that a multitude of further, alternative and / or equivalent implementations can be selected for the embodiments without essentially deviating from the basic concept of the present invention. In general, all variations, modifications and alterations of the exemplary embodiments described herein are also intended to be covered by the invention.

Detailed description of the embodiments

Fig. 1 shows a schematic representation of a compressor 100 in sectional view. The compressor 100 generally has a motor 40 which can be supported in a motor support 41. The motor 40 can be, for example, an electric motor with speed control. It may be possible to use synchronous motors such as brushless direct current motors or asynchronous motors. The engine 40 drives a drive shaft 24 that extends away from the engine 40 in a crankcase 20. The drive shaft 24 can be arranged essentially concentrically to the cross section of the crankcase shape 20 in the center thereof. The drive shaft 24 is used to drive a crank drive 6, which moves a piston 4 up and down in a cylinder 5, ie the crank drive 6 translates the rotational movement of the drive shaft 24 into a linear movement along the direction of extension of the piston 4 in the cylinder 5 the crank drive 6 have a counterweight, a crank web, a connecting rod, a connecting rod bearing and / or a piston pin. In this case, a compression chamber 11 is formed at the head end of the cylinder housing, in which air can be compressed according to the main function of the compressor 100. A fan wheel 45 can then be arranged on the crank drive 6.

A core component of the crankcase 20 is the compressed air storage tank 25, the in Fig. 1 is designed as an integral component of the crankcase 20. For this purpose, the crankcase 20 has an inner chamber wall 26a, which can be designed, for example, cylindrical with a circular or polygonal cross section, and which receives the part of the drive shaft 24 close to the engine and supports it in a rotating manner. At least one bearing 28b is therefore arranged in a first bearing seat within the chamber wall 26a. The bearing 28b in the first bearing seat can support a part of the drive shaft 24 remote from the motor between the motor 40 and the crank mechanism 6, ie the bearing 28b supports the crank mechanism 6 overhung.

In addition, a further bearing 28a can be formed in a second bearing seat within the chamber wall 26a, which can support a part of the drive shaft 24 close to the motor between motor 40 and crank mechanism 6, i.e. the bearing 28a supports the motor 40 on the fly. Because both bearings 28a and 28b are located in the section of the crankcase 20 which forms the compressed air storage tank 25, the bearing seats of the bearings 28a and 28b can be better aligned with one another. This enables an improved concentricity of the bearing seats to one another. It is possible to machine both bearing seats of the bearings 28a and 28b in the crankcase 20 from one side, especially when the radial extent of the bearing 28a is less than that of the bearing 28b.

To illustrate the geometry of the compressed air storage container 25 is shown in Fig. 2 an exemplary cross section of the compressor 100 along the cross section line AA in FIG Fig. 1 shown. The compressed air storage tank is arranged essentially in a ring around the drive shaft 24. The compressed air storage tank 25 can enclose a minimum angle of 200 °, preferably of at least 240 °, around the drive shaft 24. In the example of Fig. 2 the crankcase 20 and thus the compressed air storage tank 25 is shown in principle as a hollow cylinder. The compressed air storage container 25 is limited in the radial direction with respect to the axis of rotation of the drive shaft 24 by the inner chamber wall 26a on the one hand and an outer chamber wall 26b on the other hand.

The outer chamber wall 26b represents an outer wall of the crankcase 20, which completely accommodates the inner chamber wall 26a in its interior. In other words, the topology of the external Chamber wall 26b and the housing formed by the inner chamber wall 26a essentially resembles two cylinders mounted one inside the other, for example circular cylinders, prismatic cylinders or cylinders with a polygonal cross-sectional area. The top surfaces of the cylinder jacket surfaces formed by the outer chamber wall 26b and the inner chamber wall 26a can then be closed by one or more partition walls 34 on the other side or one or more end walls 23 on the other side to form the volume of the compressed air storage tank 25.

The partition wall 34 or the partition walls 34 have a main direction of extent which is essentially perpendicular to the axial direction of the drive shaft 24. Likewise, the end wall 23 has a main direction of extent which is essentially perpendicular to the axial direction of the drive shaft 24 and is spaced from the partition 34 or partition walls 34 by a length which substantially corresponds to the longitudinal extent of the compressed air storage tank 25.

The compressed air storage tank 25 can be interrupted in the lateral direction by one or more struts 33. As a result, the compressed air storage tank 25 can be stabilized on the one hand, and can be divided into several partial storage volumes on the other hand. These partial storage volumes can be connected to one another via compressed air lines or other connecting lines such as bottlenecks. For this purpose, compressed air coolers and / or valves can advantageously be arranged in the connecting lines. In the example of Fig. 2 three struts 33 are shown, which divide the completely circumferential compressed air storage tank 25 into three equal partial storage volumes, each of which sweeps 120 ° of the crankcase 20. Of course, other divisions with more or less partial storage volumes or asymmetrical division are also possible. The struts 33 can for example be formed integrally with the crankcase 20, for example in a common metal casting.

Fig. 3 FIG. 10 shows a detailed illustration of the compressor 100 from FIG Fig. 1 in longitudinal section. The compressor 100 is in the example Fig. 3 shown as a dry-compressing piston compressor 100 with adjustable speed, which works on the principle of reciprocating piston compression. However, it is also possible to use one instead of a dry compressing compressor use an oil-lubricated compressor. The compression can, as in Fig. 3 shown as an example, take place in one stage - but it may also be possible to carry out the compression in several stages.

The compressor according to Fig. 3 has a cylinder 5 in a compressor section 1 on the right in the figure, in which a piston 4 for compressing air from the environment is arranged. Air from the environment can be sucked into the compression chamber 11 through an intake opening 3 with an intake valve through an intake air filter 2. This takes place when the piston 4 moves downwards.

The linear working movement for the piston 5 is generated via a crank mechanism 6 which is connected to the rotor 43 of the motor 40 via a drive shaft 24. The drive shaft 24 can be mounted rotatably with respect to the crankcase 20 via two bearings 28a and 28b, for example permanently lubricated roller bearings with fixed / loose bearings. The crankcase 20 has a crank drive section 21 which at least partially encloses the crank drive 6, and a storage section 22 which adjoins the crank drive section 21 and is arranged axially between this and the motor 40.

It is preferably provided that the partition 34 separates the compressed air storage tank 25 inside the crankcase 20 from the crank drive section 21, that is, the crank drive 6 itself is not located in the air storage volume of the compressed air storage tank 25. The storage section 22 is thus formed disjoint with the crank drive section 21. In particular, it is also provided that the cylinder 5 and the piston 4 are not arranged within the storage section 22, that is to say that the volume of the compressed air storage container does not include the cylinder 5 and the piston 4.

The storage section 22 comprises an inner chamber wall 26a, which is hollow or tubular, is arranged around the drive shaft 24 and accommodates the area of the drive shaft 24 leading through the storage section 22 and at least one of the two bearings 28a and 28b. The inner chamber wall 26a can have recesses for one or more bearing seats of the bearings 28a and 28b. In addition, more than two bearings 28a and 28b can be provided.

The storage section 22 further comprises an outer chamber wall 26b, which can be arranged concentrically around the inner chamber wall 26a and at a distance therefrom. The inner chamber wall 26a and the outer chamber wall 26b are preferably integral with the crankcase 20, i. designed as an integral part of the crankcase 20.

The inner chamber wall 26a and the outer chamber wall 26b define, together with one or more partition walls 34, the plane of extension of which is essentially perpendicular to the axis of rotation of the drive shaft 24, a compressed air storage container 25 of the compressor 100. The compressed air storage container 25 is concentric to the drive shaft 24, at least in sections, annular around the inner chamber wall 26a arranged. In other words, the compressed air storage container 25 thus encloses the drive shaft 24 at least in a partial angular range. In the example of Fig. 3 the compressed air storage container 25 is arranged completely, that is to say in an angular range of 360 °, around the drive shaft 24. However, it may also be possible to provide only partial angular areas of less than 360 ° around the drive shaft 24, in which angular chambers for the functioning of the compressed air storage container 25 are defined by the chamber walls 26a and 26b and the partition walls 34. On the engine side, the compressed air storage tank 25 is sealed off by an end wall 23 of the crankcase 20 with respect to the engine area or the engine support 41. The compressed air storage tank 25 thus defines a control volume via the corresponding dimensions of the chamber walls 26a and 26b and the axial distance L3 between the partition walls 34 and the end wall 23 of the crankcase 20, which is used to receive and temporarily store compressed air generated by the piston compressor.

The motor support 41 can take over the torque support between the rotor and stator of the motor 40. The motor support 41 can be a component that completely or only partially surrounds the motor 40 and can have closed boundary walls with struts, pillars or the like. The motor support 41 can also function as a completely closed motor housing.

The motor support 41 can also form the end wall 23, which in the example of FIG Fig. 3 is arranged between motor 40 and storage section 22. However, it can also be provided to arrange the end wall 23 on the outside of the motor 40, so that the motor 40 at least partially through the Storage section 22 is included, that is to say that the volume of the compressed air storage tank 25 extends in the axial direction of the drive shaft 24 at least partially completely or in a partial angular range around the motor 40.

After a suction work cycle of the piston 4, the sucked air is compressed in the compression chamber 11 in a compressor work cycle during the upward movement of the piston 4 and discharged via the outlet opening 7 and an outlet valve arranged therein. The compressed air that is expelled via the outlet opening 7 can be discharged into a compressed air line 8, which can include an area with a cooling line 9 for cooling purposes. Via the cooling line 9, the compressed air passes through the check valve 10 into a compressed air storage container 25 of the compressor 100.

The seal with respect to the environment can expediently take place via seals 29 and 30, for example O-rings. Both the crankcase 20 and the engine support 41 can be reinforced by ribs 32. These ribs 32, which can also be attached in a similar form on the outside of the crankcase 20 and / or the motor support 41, contribute to better heat dissipation from the compressed air. It is also possible to optimize the mechanical stability of the compressor 100 in this way.

A compressed air delivery line, for example a compressed air hose for a compressed air-operated tool, through which the compressed air can be taken from the compressed air storage container 25 as required, can be connected via a compressed air coupling 31.

During the compressor operation, a compressor control 60 can call up the pressure of the compressed air measured by a pressure sensor 27 arranged on the compressed air storage container 25 via a control line 61. Should the measured actual pressure in the compressed air storage tank 25 deviate from the setpoint pressure stored in the compressor control 60, a setpoint speed signal for the motor 40 can be determined from the control deviation, which the compressor control 60 sends as a control signal via a control line 62 to an engine control, for example the frequency converter 70 of an electric motor 40 are output. The frequency converter 70 regulates the speed of the motor 40 as a function of the transmitted control signal.

In the example of Fig. 3 the motor 40 is an electronically commutated synchronous external rotor motor in which the frequency converter 70 is attached directly to the stator 44. The stator 44 carries the stator winding 46 and can be connected to the motor support 41 by means of screws, for example. Via the alternating magnetic field generated in the stator winding 46, the torque required for compressing the compressor 100 is generated in a known manner in interaction with the permanent magnets 48 in the rotor 43 of the motor 40.

Fig. 4 shows a longitudinal section through a compact variable-speed piston compressor 100 with an alternative motor design. It differs from the 100 in Fig. 1 essentially that the motor 40 is an internal rotor motor with an external frequency converter. In Fig. 5 is a more detailed illustration of the compressor's Fig. 4 shown. Here the motor 40 has an external frequency converter 70, which is connected to the motor 40 via a motor connection cable 47. If, for assembly reasons, the engine 40 cannot be attached to the crankcase 20 with the engine mount 41, the compressor can use the Fig. 5 In addition, a cover can be provided as an end wall 23. On the one hand, the cover 23 can fasten the motor 40 to the motor support 41, which can then take on a housing function for the motor 40. On the other hand, the cover 23 can fluidically close the compressed air storage container 25 located in the crankcase 20.

Both for the compressor 100 of the Figs. 1 to 3 as well as the compressor 100 of the Fig. 4 and 5 the maximum radial extension L2 (distance of the axis of rotation of the drive shaft 24 to the point on the inner wall of the compressed air storage container 25 that is most vertically spaced from the drive shaft 24) in a certain ratio to the compressor length L1 (distance of the axis of rotation of the drive shaft 24 to the top dead center of the piston) stand. In the simplest case, the dimension L2 can be less than or equal to the compressor length L1. A ratio of L2 / L1 2/3 is advantageous here. The ratio L2 / L1 can be between 0.2 and 1, preferably between 0.4 and 0.66. Viewed in absolute terms, the dimension L2 can be less than 150 mm in order to ensure, for example, the compactness and thus the hand portability of the compressor 100.

Likewise, the maximum radial extent L2 can be in a certain ratio to the maximum axial extent L3 of the compressed air storage container 25. If the compressed air storage tank 25 is arranged between the crank mechanism 6 and the motor 40, the ratio L2 / L3 can be between 0.3 and 2.5, preferably between 0.5 and 1.33.

In addition, the volume ratio between the volume V _{R of} the compressed air storage tank 25 and the geometric stroke volume V _{H of} the compressor chamber 11 (or the sum V _{H of} all the stroke volumes V _{Hi of} all the compressor chambers 11 in the case of several cylinders 5) can be set in order to optimally dampen the compressed air pulsations to be able to eliminate. The ratio V _R / V _{H can be} between 5 and 25.

The crankcase 20 together with all chamber walls 26a, 26b and end walls 23 and partition walls 34 can be in the Figs. 1 to 5 be formed completely integrally, for example by a casting process with a lost shape or a rapid prototyping process such as selective laser melting, 3D printing, additive layer manufacturing, electron beam melting, laser deposition welding or similar processes. Alternatively, it may also be possible to assemble the chamber walls 26a, 26b from several parts which are sealed and connected, preferably screwed, to one another. The crankcase 20 and its relevant components such as walls, partition walls and end walls can be produced, for example, in a die-casting process, for example from a light metal such as aluminum or magnesium.

Fig. 6 , 7 and 8 show schematic representations of further variants of a compressor 100. The compressors 100 of FIG Fig. 6 and 7th differ from the compressors 100 of the Fig. 1 and 4th essentially in that the second bearing 28a is accommodated in the motor 40 - in Fig. 6 on the side of the engine 40 remote from the crankcase, in Fig. 7 on the side of the engine 40 close to the crankcase. The compressor 100 of Fig. 8 has a crankcase 20 which, together with the motor support 41, forms a compressed air storage tank 25 which is expanded axially on the drive shaft. The compressed air storage tank 25 extends around the engine 40 in the interior of the crankcase 20, which is spaced from the engine support 41 accordingly. The ratio L2 / L1 of the maximum radial expansion L2 to the maximum axial expansion L1 of the Compressed air storage container 25 between 0.12 and 1, preferably between 0.2 and 0.5.

The compressed air storage tank 25 can surround the motor 40 in a partial angular range of less than 360 ° or completely, that is to say to a circumference of 360 °. It may furthermore be possible that the compressed air storage tank 25 completely surrounds the motor 40 with respect to the angular range around the drive shaft 24, but only partially surrounds the motor 40 in the axial direction of the motor axis of rotation, that is, is not completely formed as far as the end of the motor support 40 remote from the crankcase .

List of reference symbols

1

Compressor section

2

Air intake filter

3

Inlet opening

4th

piston

5

cylinder

6th

Crank drive

7th

Outlet opening

8th

Compressed air line

9

Cooling line

10

check valve

11

Compression space

20th

Crankcase

21st

Crank drive section

22nd

Memory section

23

End wall

24

drive shaft

25th

Compressed air storage

26a

Inner chamber wall

26b

Outer chamber wall

27

Pressure sensor

28a

First camp

28b

Second camp

29

poetry

30th

poetry

31

Compressed air coupling

32

rib

33

Bracing

34

partition wall

40

engine

41

Engine mount

43

rotor

44

stator

45

Fan wheel

46

Stator winding

47

Motor connection cable

48

Permanent magnets

60

Compressor control

61

Control line

62

Control line

70

frequency converter

L1

Compressor length

L2

Crankcase inner radius

L3

Storage length

Claims (15)

1. Piston compressor (100), having:

   a motor (40);

   a drive shaft (24) that is connected to the motor (40) and is driven by this motor;

   a crankshaft (6) that is connected to the drive shaft (24);

   at least one compressed air generating device (4; 5; 11) having a piston (4) that can move in a cylinder (5) and is driven by means of the crankshaft (6) and is embodied for the purpose of generating compressed air in a compression chamber (11) of the cylinder (5);

   a crankcase (20), which comprises

   an inner chamber wall (26a) in the form of a hollow body that receives the drive shaft at least in sections,

   an outer chamber wall (26b) that is spaced radially with respect to the drive shaft (24) from the inner chamber wall (26a),

   an end wall (23), and

   a dividing wall (34); and

   a compressed air storage container (25), which is embodied for the purpose of receiving the compressed air that is generated by the compressed air generating device (4; 5; 11), wherein the compressed air storage container (25) is formed by means of the inner chamber wall (26a), the outer chamber wall (26b), the end wall (23) and the dividing wall (34).
2. Piston compressor (100) according to claim 1, furthermore having:
   a motor carrier (41), which receives the motor (40) and is connected to the crankcase (20) while forming the end wall (23) between the crankcase (20) and motor (40).
3. Piston compressor (100) according to one of claims 1 and 2, furthermore having:
   at least one first bearing arrangement (28b), which bears the drive shaft (24) and which is arranged within the hollow body that is formed by means of the inner chamber wall (26a).
4. Piston compressor (100) according to claim 3, furthermore having:
   at least one second bearing arrangement (28a), which bears the drive shaft (24) and which is arranged within the hollow body that is formed by means of the inner chamber wall (26a) between the motor (40) and the first bearing arrangement (28b).
5. Piston compressor (100) according to one of claims 1 to 4, wherein the crankcase (20) is embodied in a monolithic manner with the inner chamber wall (26a), the outer chamber wall (26b) and the dividing wall (34).
6. Piston compressor (100) according to claim 5, wherein the monolithic crankcase (20) is embodied as a light metal casting part.
7. Piston compressor (100) according to one of claims 1 to 6, furthermore having:
   at least one strut (33), which extends axially with respect to the drive shaft (24) between the inner chamber wall (26a) and the outer chamber wall (26b).
8. Piston compressor (100) according to claim 7, wherein the at least one strut (33) divides the compressed air storage container (25) into at least two part storage regions.
9. Piston compressor (100) according to claim 8, wherein the at least two part storage regions are connected to one another so that fluid can pass from one storage region to another by means of compressed air lines, valves, and/or bottlenecks.
10. Piston compressor (100) according to one of claims 1 to 9, furthermore having:

    a motor carrier (41), which receives the motor (40),

    wherein the crankcase (20) is embodied around the motor (40) spaced from the motor carrier (41), and

    wherein the compressed air storage container (25) extends at least in part around the motor (40) between the crankcase (20) and motor carrier (41).
11. Piston compressor (100) according to one of claims 1 to 9, wherein the end wall (23) is arranged in the axial direction of the drive shaft (24) between the crankcase (20) and motor (40).
12. Piston compressor (100) according to one of claims 1 to 11, wherein the compressed air storage container (25) encompasses the drive shaft (24) in an angular range of 360°.
13. Piston compressor (100) according to one of claims 1 to 12, wherein the ratio of the distance (L2) to the distance (L1) is between 0.2 and 1, said distance (L2) being the distance between the rotational axis of the drive shaft (24) and the point on the inner wall of the compressed air storage container (25), said point being spaced furthest perpendicularly from the drive shaft (24), and said distance (L1) being the distance between the rotational axis of the drive shaft (24) and the upper dead centre of the piston (4) of the compressed air generating device (4; 5; 11).
14. Piston compressor (100) according to one of claims 1 to 13, wherein the ratio of the distance (L2) to the maximum axial extent (L3) of the compressed air storage container (25) is between 0.3 and 2.5, said distance (L2) being the distance between the rotational axis of the drive shaft (24) and the point on the inner wall of the compressed air storage container (25), said point being spaced furthest perpendicularly from the drive shaft (24).
15. Piston compressor (100) according to one of claims 1 to 14, wherein the compressed air generating device (4; 5; 11) comprises at least one compression chamber (11) and wherein the volume ratio between the volumes (V_R) of the compressed air storage container (25) and the sum of the geometric piston displacements (V_H) of the compression chambers (11) of the compressed air generating device (4; 5; 11) is between 5 and 25.

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