Compressor, compressed air supply facility for operating a pneumatic system, and method for operating a compressed air supply facility

1. A compressor for a compressed-air feed of a compressed-air supply installation, for operating a pneumatic installation, comprising:

a cylinder comprising a rotationally symmetrical cylinder inner web that extends radially inward from a cylinder inner wall of the cylinder, the cylinder inner web comprising a web wall having a web wall inner side;

a first compression space;

a second compression space;

an air feed port;

a compressed-air outlet; and

a piston having a first face side, which is subjectable to pressure and which is directed toward the first compression space, and a second face side, which is situated opposite the first face side and which is subjectable to pressure and which is directed toward the second compression space, the first compression space being delimited by the first face side and the second compression space being delimited by the second face side,

wherein the first face side comprises a full side and the second face side comprises a step side,

wherein the piston is attached via a connecting rod to a drive,

wherein the first compression space and the second compression space are connected to one another via a connecting line,

wherein the connecting rod is connected rigidly at a piston side to the piston and, at a drive side, is connected rotatably to a rotating part of the drive, and

wherein the piston bears, on the step side, on at least one seal which seals off the first compression space and the second compression space.

2. The compressor as claimed in claim 1 , wherein the piston comprises a check valve configured to open automatically, counter to a spring force, from the first compression space in a direction of the air feed port.

3. The compressor as claimed in claim 1 , wherein the connecting rod is rotatably connected to the rotating part of the drive in a form of an eccentrically arranged shaft portion.

4. The compressor as claimed in claim 1 , wherein the connecting rod comprises a single piece with the piston and without articulation with respect to the piston.

5. The compressor as claimed in claim 1 , wherein the first compression space is of cylindrical form or is of cylindrical form with a dome-shaped portion, and/or the second compression space is of annular cylindrical form.

6. The compressor as claimed in claim 1 , wherein the seal is configured to seal off the second compression space with respect to a crankcase interior space and/or with respect to surroundings.

7. The compressor as claimed in claim 1 , wherein the at least one seal on the step side of the piston provides pressure-tight sealing, which acts in a radial direction, both against an outer side and against an inner side, and

wherein the at least one seal comprises a single seal.

8. The compressor as claimed in claim 7 , wherein the outer side of the seal is in encircling contact with the cylinder inner wall, and the inner side of the at least one seal is in encircling contact with the web wall inner side.

9. The compressor as claimed in claim 7 , wherein the seal comprises an annular seal body with a first annular lip radially at an outside on the seal body and with a second annular lip radially at an inside on the seal body.

10. The compressor as claimed in claim 7 , wherein the seal comprises an annular seal body, having:

a first annular lip, which is arranged in a radial direction at an outside on the seal body so as to be directed in an axial direction toward the second compression space, and/or

a second annular lip, which is arranged in the radial direction at an inside on the seal body so as to be directed in the axial direction toward the second compression space.

11. The compressor as claimed in claim 10 , wherein the annular seal body comprises a third annular lip which is arranged in the radial direction at the outside on the seal body so as to be directed in the axial direction toward the first compression space.

12. The compressor as claimed in claim 1 , wherein the piston comprises a non-cylindrical outer cross section which varies in an axial direction.

13. The compressor as claimed in claim 1 , wherein the second compression space comprises a charging port configured for additional feed of compressed air from a pressure medium reservoir.

14. The compressor as claimed in claim 1 , wherein the air feed port is arranged within the connecting rod and/or the piston.

15. The compressor as claimed in claim 1 , wherein the rotatable connection between connecting rod and an eccentrically arranged shaft portion of the drive comprises a connecting-rod bearing comprising a plain bearing, ball bearing, or a needle-roller bearing.

16. A compressed-air supply installation for operating a pneumatic installation, comprising:

an air feed;

the compressor as claimed in claim 1 , connected to the air feed via an air feed port;

a pneumatic main line pneumatically connected to the compressor via a compressed-air outlet, the pneumatic main line comprising an air dryer, the pneumatic main line being connected to a compressed-air port of a gallery; and

a pressure medium reservoir pneumatically connected to the compressor via a charging port.

17. A method for operating the compressed-air supply installation as claimed in claim 16 , comprising:

compressing air from a crankcase interior space and/or from surroundings to a low pressure level in a first compression space of the compressor;

further compressing the compressed air that has been compressed to a low pressure level in the first compression space to a high pressure level in a second compression space of the compressor; and

feeding the compressed air that has been compressed to a high pressure level in the second compression space from the compressed-air outlet via a pneumatic main line to a compressed-air port of a gallery via an air dryer.

18. A vehicle having the compressed-air supply installation as claimed in claim 16 .

19. The compressor as claimed in claim 1 , wherein the compressor comprises a compression blower.

20. The compressor as claimed in claim 1 , wherein the connecting rod is connected rigidly and without articulation at the piston side to the piston.