COMPRESSOR AND METHOD FOR COMPRESSING A WORKING MEDIUM

Abstract

A compressor and method for compressing a working medium, including moving a drive piston which is driven by way of a driving medium within a first cylinder between a first end position and a second end position; moving a high pressure piston which compresses the working medium within a second cylinder between a first end position and a second end position; arranging a high pressure seal for sealing the high pressure piston; arranging a magazine having a receptacle for the high pressure seal and at least one replacement high pressure seal in a first operating position, in which the high pressure piston is sealed by way of the high pressure seal; and transferring the magazine from the first operating position to a second operating position, in which the high pressure piston is sealed by way of the replacement high pressure seal.

Claims

1. A method for compressing a working medium comprising the steps: moving a drive piston driven by means of a drive medium within a first cylinder between a first end position and a second end position; moving a high-pressure piston which compresses the working medium within a second cylinder between a first end position and a second end position; and arranging a high-pressure seal for sealing the high-pressure piston; wherein: arranging a magazine with a receptacle for the high-pressure seal and with at least one replacement high-pressure seal in a first operating position in which the high-pressure piston is sealed by the high-pressure seal; and transferring the magazine from the first operating position into a second operating position in which the high-pressure piston is sealed by the replacement high-pressure seal.

2. The method according to claim 1, wherein the transfer of the magazine from the first operating position into the second operating position comprises: shifting the magazine together with the high-pressure seal arranged in the receptacle relative to the second cylinder substantially in a direction of a central axis of the high-pressure piston from the first operating position into a first intermediate position which releases the high-pressure seal from the high-pressure piston; transferring the magazine from the first intermediate position into a second intermediate position which arranges the replacement high-pressure seal substantially coaxially with the high-pressure piston; and shifting the magazine together with the replacement high-pressure seal substantially in the direction of the central axis of the high-pressure piston from the second intermediate position into the second operating position.

3. The method according to claim 2, wherein the shifting of the magazine from the first operating position into the first intermediate position comprises: releasing the high-pressure piston from the drive piston; arranging the drive piston and the high-pressure piston at a distance from one another; and shifting the magazine from the first operating position substantially in the direction of the central axis of the high-pressure piston so that the high-pressure seal in the first intermediate position, when viewed in the direction of the central axis of the drive piston, is arranged between the high-pressure piston and the drive piston.

4. The method according to claim 1, wherein the transfer of the magazine from the first operating position into the second operating position comprises: shifting the magazine together with the high-pressure seal arranged in the receptacle jointly with the second cylinder substantially in a direction of a central axis of the high-pressure piston away from the drive piston from the first operating position into a first intermediate position which releases the high-pressure seal from the high-pressure piston; transferring the magazine from the first intermediate position into a second intermediate position which arranges the replacement high-pressure seal substantially coaxially with the high-pressure piston; and shifting the magazine together with the replacement high-pressure seal jointly with the second cylinder substantially in the direction of the central axis of the high-pressure piston towards the drive piston from the second intermediate position into the second operating position.

5. The method according to claim 1, wherein the transfer of the magazine into the second operating position comprises: shifting the high-pressure piston substantially in a direction of a central axis of the high-pressure piston away from the magazine together with the high-pressure seal arranged in the receptacle until the high-pressure seal is released from the high-pressure piston so that the magazine is arranged in a first intermediate position; transferring the magazine from the first intermediate position into a second intermediate position which arranges the replacement high-pressure seal substantially coaxially with the high-pressure piston; and shifting the high-pressure piston substantially in the direction of the central axis of the high-pressure piston towards the magazine until the replacement high-pressure seal is arranged on the high-pressure piston.

6. The method according to claim 1, wherein the transfer of the magazine from the first operating position into the second operating position comprises: shifting the high-pressure seal from a position arranged outside the receptacle when viewed in a direction of a central axis of the high-pressure piston into a position arranged in the receptacle, wherein the replacement high-pressure seal is arranged in a further receptacle of the magazine, so that the magazine is arranged in a first intermediate position; transferring the magazine from the first intermediate position into a second intermediate position which arranges the replacement high-pressure seal substantially coaxially with the high-pressure piston; and shifting the replacement high-pressure seal from the position arranged in the further receptacle of the magazine into a position arranged outside the further receptacle of the magazine when viewed in the direction of the central axis of the high-pressure piston.

7. The method according to claim 6, wherein the high-pressure seal and the replacement high-pressure seal are each shifted jointly with the second cylinder.

8. The method according to claim 2, wherein for transfer from the first intermediate position into the second intermediate position, the magazine is pivoted about a pivot axis running substantially parallel to the central axis of the high-pressure piston or is shifted substantially in the direction perpendicular to the central axis of the high-pressure piston.

9. A compressor for compressing a working medium comprising: a drive piston which can be actuated with a working medium within a first cylinder, wherein the drive piston is movable between a first end position and a second end position; a high-pressure piston which compresses the working medium within a second cylinder, wherein the high-pressure piston is movable between a first end position and a second end position; a high-pressure seal for sealing the high-pressure piston; a magazine with a receptacle for the high-pressure seal and with at least one replacement high-pressure seal; a changeover device with a drive for transferring the magazine between a first operating position for sealing the high-pressure piston by the high-pressure seal and a second operating position for sealing the high-pressure piston by the replacement high-pressure seal.

10. The compressor according to claim 9, wherein a sensor device for detecting a leakage of the working medium is provided, wherein a control device is connected to the sensor device and to the changeover device, in order to transfer the magazine from the first operating position into the second operating position upon detecting a leakage of the working medium.

11. The compressor according to claim 9, wherein the changeover device for transferring the magazine from the first operating position into a second operating position is adapted a. to shift the magazine together with the high-pressure seal arranged in the receptacle substantially in the direction of the central axis of the high-pressure piston relative to the second cylinder and/or b. to shift the magazine together with the second cylinder substantially in the direction of the central axis of the high-pressure piston and/or c. to shift the high-pressure piston substantially in the direction of the central axis of the high-pressure piston beyond the first or second end position and/or d. to shift the second cylinder substantially in the direction of the central axis of the high-pressure piston in order to bring the high-pressure seal from a position arranged axially outside the receptacle into a position arranged in the receptacle.

12. The compressor according to claim 11, wherein the changeover device is further adapted for transferring the magazine from the first intermediate position into a second intermediate position which arranges the replacement high-pressure seal substantially coaxially with the high-pressure piston.

13. The compressor according to claim 12, wherein the changeover device for transferring the magazine from the second intermediate position into the second operating position is adapted a. to shift the magazine together with the replacement high-pressure seal arranged in the receptacle substantially in the direction of the central axis of the high-pressure piston relative to the second cylinder and/or b. to shift the magazine together with the second cylinder substantially in the direction of the central axis of the high-pressure piston and/or c. to shift the high-pressure piston substantially in the direction of the central axis of the high-pressure piston back into the first or second end position and/or d. to shift the second cylinder substantially in the direction of the central axis of the high-pressure piston in order to bring the replacement high-pressure seal from a position arranged in a further receptacle of the magazine into a position arranged axially outside the further receptacle.

14. The compressor according to claim 9, wherein the high-pressure seal and the replacement high-pressure seal each have a housing in which at least one sealing element is arranged detachably.

15. The compressor according to claim 9, wherein the magazine comprises between 2 and 7 replacement high-pressure seals.

16. The method of claim 4, wherein for transfer from the first intermediate position into the second intermediate position, the magazine is pivoted about a pivot axis running substantially parallel to a central axis of the high-pressure piston or is shifted substantially in a direction perpendicular to the central axis of the high-pressure piston.

17. The method of claim 5, wherein for transfer from the first intermediate position into the second intermediate position, the magazine is pivoted about a pivot axis running substantially parallel to a central axis of the high-pressure piston or is shifted substantially in a direction perpendicular to the central axis of the high-pressure piston.

18. The method of claim 6, wherein for transfer from the first intermediate position into the second intermediate position, the magazine is pivoted about a pivot axis running substantially parallel to a central axis of the high-pressure piston or is shifted substantially in a direction perpendicular to the central axis of the high-pressure piston.

19. The compressor of claim 10, wherein the high-pressure seal and the replacement high-pressure seal each have a housing in which at least one sealing element is arranged so as to be detachable, and wherein the magazine comprises between 2 and 7 replacement high-pressure seals.

20. The compressor of claim 13, wherein the high-pressure seal and the replacement high-pressure seal each have a housing in which at least one sealing element is arranged so as to be detachable, and wherein the magazine comprises between 2 and 7 replacement high-pressure seals.

Description

[0089] The invention is explained in further detail hereinafter with reference to exemplary embodiments shown in the drawings.

[0090] FIG. 1 shows a first embodiment of a compressor according to the invention with a drive piston and a high-pressure piston in a middle position, wherein a magazine with a high-pressure seal and a replacement high-pressure seal are arranged in a first operating position.

[0091] FIG. 2 shows the compressor according to FIG. 1 wherein drive piston and high-pressure piston are arranged in the other end position.

[0092] FIG. 3 shows the compressor according to FIGS. 1, 2 wherein after releasing a clamping device the drive piston is moved away from the high-pressure piston so that a free space is formed between drive piston and high-pressure piston.

[0093] FIG. 4 shows the compressor according to FIGS. 1 to 3 in a first intermediate position of the magazine, in which the high-pressure seal is shifted into the free space between drive piston and high-pressure piston.

[0094] FIG. 5 shows the compressor according to FIGS. 1 to 4 in a changeover position after pivoting the magazine from the first intermediate position, wherein the replacement high-pressure seal is arranged adjacent to the high-pressure piston.

[0095] FIG. 6 shows the compressor according to FIGS. 1 to 5, wherein the replacement high-pressure seal is pushed onto the high-pressure piston.

[0096] FIG. 7 shows the compressor according to FIGS. 1 to 6 in the second operating position wherein the high-pressure piston is again coupled to the drive piston.

[0097] FIGS. 8 to 12 each show a second embodiment of the compressor according to the invention with a magazine which is displaceable in the axial and radial direction, wherein FIG. 8 shows the first operating position, FIG. 9 shows the first intermediate position, FIG. 10 shows a state between the first and second intermediate position, FIG. 11 shows the second intermediate position and FIG. 12 shows the transfer into the second operating position.

[0098] FIGS. 13, 14 each show a third embodiment of the compressor according to the invention in which the release of the high-pressure seal from the high-pressure piston is effected by shifting the high-pressure piston between the first operating position (cf. FIG. 13) and a first intermediate position (cf. FIG. 14).

[0099] FIGS. 15, 16 each show a fourth embodiment of the compressor according to the invention in which the high-pressure seal in the first operating position (cf. FIG. 15) is arranged outside a receptacle of the magazine and is pushed into the receptacle by means of the second cylinder (cf. FIG. 16).

[0100] FIGS. 1 to 7 show a first embodiment of a compressor 1 for compressing a gaseous working medium, for example, molecular hydrogen. The compressor 1 comprises a pressure translator with a drive piston 2, which is moved to and fro within a first cylinder 3 between a first end position (cf. FIG. 2) and a second end position (not shown). A gaseous drive medium, in particular compressed air, is used for the drive of the drive piston 2. The drive piston 2 seals a first volume 4 of the first cylinder 3 by means of a seal 5 with respect to a second volume 6 of the first cylinder 3. Further provided is a high-pressure piston 7 which compresses the working medium, which is moved to and fro within a second cylinder 8 between a first end position (cf. FIG. 2) and a second end position (not shown). The high-pressure piston 7 has a smaller piston area than the drive or low-pressure piston 2 so that a pressure translation from the low-pressure to the high-pressure side is achieved. For coupling the high-pressure piston 7 to the drive piston 2, a detachable clamping device 9 is provided in the first embodiment. This clamping device 9 is known per se so that more detailed explanations can be superfluous. In other embodiments, see FIGS. 8 to 16, the high-pressure piston 7 can be fixedly connected to the drive piston 2 in order to transmit the movement of the drive piston 2 to the high-pressure piston 7.

[0101] The compressor 1 additionally comprises a magazine 10 which is equipped with a receptacle 11a for a high-pressure seal 11 and with at least one further receptacle 12a for a replacement high-pressure seal 12. The high-pressure seal 11 brings about the sealing of the high-pressure piston 7 in a first operating position during compression of the working medium. The replacement high-pressure seal 12 brings about the sealing of the high-pressure piston 7 in a second operating position of the magazine 10 which is different from this, during compression of the working medium. Furthermore, a changeover device 13 is provided for independent exchange of the high-pressure seal 11 by the replacement high-pressure seal 11. The changeover device 13 has a drive 14 (only shown schematically in FIG. 1) by means of whichas will be explained in detail hereinafter, the magazine 10 can be moved from the first operating position into the second operating position (and conversely).

[0102] As is further apparent schematically from FIG. 1, a sensor device 15 is provided for detecting a leakage of the working medium. The sensor device 15 is connected to a leakage line 16 at which escaping working medium (possibly also escaping drive medium) can be detected. The sensor device 15 canas is known per se in the prior arthave a pressure measuring element for detecting the gas pressure in the leakage line 16. Additionally or alternatively, the sensor device 15 can be adapted for qualitative or quantitative gas measurement. A plurality of possibilities are known for this in the prior art, based on electrical, physical and/or chemical measurement principles so that this need not be discussed in detail. In addition, the compressor 1 has an electronic control device 17 which on the one hand is connected to the sensor device 15 and on the other hand is connected to the changeover device 13. If a leakage of the working medium is detected at the sensor device 15, the drive 14 of the changeover device 13 is actuated by the control device 17 in such a manner that the magazine 10 is moved from the first operating position into the second operating position in order to arrange the replacement high-pressure seal 12 on the high-pressure piston 7.

[0103] In the embodiment shown the high-pressure seal 11 and the replacement high-pressure seal 12 each have a housing 18 in which at least one annularly circumferential sealing element 19 is arranged in a reversibly detachable manner. In the embodiment shown the high-pressure seal 11 and the replacement high-pressure seal 12 each have a first annularly circumferential sealing element 19a for sealing a high-pressure side and a second annularly circumferential sealing element 19b for sealing a low-pressure side of the compressor 1. Furthermore, in the embodiment shown the high-pressure seal 11 and the replacement high-pressure seal 12 each have an annularly circumferential bearing element 20, in the embodiment shown a guide band, for mounting the high-pressure piston 7.

[0104] Depending on the design, the magazine 10 can have a plurality of replacement high-pressure seals 12. In many cases it is favourable if between 2 and 7 replacement high-pressure seals 12 are provided on the magazine 10.

[0105] Only the essential components of the compressor for the understanding of the invention are shown in the drawing. For the person skilled in the art it is clear that the compressor can typically have numerous further components which, however, are sufficiently known in the prior art.

[0106] In the first embodiment of FIGS. 1 to 7, the magazine 10 is displaceable on the one hand in the direction of a central axis 21 of the high-pressure piston and on the other hand, is pivotable about a pivot axis running parallel and at a distance thereto. For this purpose, the drive 14 of the changeover device 13 according to FIGS. 1 to 7 has a drive rod 14a which can be displaced in the longitudinal direction and which can be pivoted about its own longitudinal axis 14b.

[0107] FIGS. 1 to 7 illustrate the individual steps on changing from the first operating position using the high-pressure seal 11 into the second operating position using the replacement high-pressure seal 12.

[0108] According to FIG. 1 and FIG. 2, the magazine 1 is arranged in the first operating position in which the high-pressure piston 7 is sealed by the high-pressure seal 11. The high-pressure piston 7 is coupled via the clamping device 9 to the drive piston 2 so that the high-pressure piston 7 and drive piston 2 can move synchronously to and fro. FIG. 1 shows drive piston 2 and high-pressure piston 7 each in a central position between the opposite dead points. FIG. 2 shows the drive piston 2 in the first end position and the high-pressure piston 7 in the first end position.

[0109] According to FIG. 3, the clamping device 9 is in the released state wherein the high-pressure piston 7 is decoupled from the drive piston 2. The high-pressure piston 7 is arranged on the first end position and the drive piston 2 is arranged in the second end position so that a maximum distance in the axial direction is achieved between high-pressure piston 7 and drive piston 2. In order to reach this state, a magnet element can be provided which holds the high-pressure piston 7 firmly in the first end position released from the drive piston 2. A permanent magnet 22a or a magnetic coil 22b can be provided as magnet element. In the embodiment shown, the magnetic coil 22b is arranged concentrically about the high-pressure piston 7 on the second cylinder 8. Furthermore, the rest position of the high-pressure piston 7 can be achieved by a pressure difference between the first volume 4 of the first cylinder 3 and a high-pressure volume 23 of the second cylinder 8. This is achieved by relieving the pressure of the high-pressure volume 23, wherein the first volume 4 remains pressurized. The resulting force presses the high-pressure piston 7 into the first end position.

[0110] According to FIG. 4, the magazine 10 is arranged in a first intermediate position displaced axially towards the drive piston 2. Since the high-pressure piston 7 and the drive piston 2 are arranged in opposite end positions, the high-pressure seal 11 is located on the magazine 10 when viewed in the axial direction between the end of the high-pressure piston 7 released from the drive piston 2 and the drive piston 2. The central axis 11a of the high-pressure seal 11 is arranged collinearly to the central axis 21 of the high-pressure piston 7. The central axis 12a of the replacement high-pressure seal 12 is arranged parallel to and in the radial direction at a distance from the central axis 21 of the high-pressure piston 7.

[0111] According to FIG. 5, the magazine 10 is in a first intermediate position in which the central axis 12a of the replacement high-pressure seal 12 is arranged substantially collinearly with the central axis 21 of the high-pressure piston 7. The central axis 11a of the high-pressure seal 11 is now arranged parallel to and in the radial direction at a distance from the central axis 21 of the high-pressure piston 7. In order to reach the changeover position, starting from the first intermediate position, the magazine 10 is pivoted about the pivot axis 14b (cf. arrow 24 in FIG. 4). The pivot angle depends on the number and the arrangement of the replacement high-pressure seals 12 on the magazine 10.

[0112] According to FIG. 6, the replacement high-pressure seal 12 is pushed onto the high-pressure piston 7. For this purpose, starting from the first intermediate position (cf. FIG. 5), the magazine 10 is displaced in the axial direction away from the drive piston 2 until the replacement high-pressure seal 12 sits on the high-pressure piston 7.

[0113] According to FIG. 7, the drive piston 2 is again coupled to the high-pressure piston 7 so that operation of the compressor 1, now with the exchanged replacement high-pressure seal 12, can be continued.

[0114] FIGS. 8 to 12 show a further embodiment of the compressor 1, wherein only the differences from the embodiment of FIGS. 1 to 7 will be discussed hereinafter.

[0115] In this embodiment, the magazine 10 together with the second cylinder 8 for the high-pressure piston 7 is displaced from the first operating position (cf. FIG. 8) away from the first cylinder 3 for the drive piston 2 into the first intermediate position (cf. FIG. 9). Thus, the clamping device 9 for the detachable coupling between drive piston 2 and high-pressure piston 7 can be omitted.

[0116] Furthermore, this embodiment differs from that of FIGS. 1 to 7 in that the changeover device 13 is adapted for shifting the magazine 10 in the direction perpendicular to the central axis 21 of the high-pressure piston 7, i.e. in the radial direction, from the first intermediate position into the second intermediate position (and conversely).

[0117] Thus, the following steps are carried out when changing from the high-pressure seal 11 to the replacement high-pressure seal 12.

[0118] According to FIG. 8, the compressor 1 is arranged in the first operating position in which the high-pressure seal 11 on the magazine 10 brings about the sealing of the high-pressure piston 7. The central axis 11a of the high-pressure seal 11 coincides with the central axis 21 of the high-pressure piston 21. The replacement high-pressure seal 12 is arranged in a waiting position remote from the high-pressure piston 7 in the radial direction. The drive piston 2 is located in the end position shifted away from the magazine 10 (cf. arrow 25a).

[0119] According to FIG. 9, the magazine 10 together with the second cylinder 8 is shifted in the axial direction (cf. arrows 25b) so that the magazine 10 enters into the first intermediate position. During this the drive piston 2 and the high-pressure piston 7 are arranged in the end position shifted away from the magazine 10. Thus, during displacement of the magazine 10 with the second cylinder 8, the high-pressure seal 11 slips away from the end of the high-pressure piston 7.

[0120] According to FIG. 10, the magazine 10 is shifted relative to the second cylinder 8 in the radial direction (cf. arrow 26b).

[0121] According to FIG. 11, as a result of further shifting in the direction of the arrow 26b, the magazine 10 enters into the second intermediate position in which the replacement high-pressure seal 12 on the magazine 10 is arranged collinearly with the high-pressure piston 7 but outside thereof in the axial direction.

[0122] According to FIG. 12, the magazine 10 together with the second cylinder 8 is pushed in the axial direction onto the high-pressure piston 7 (cf. arrow 27) until the second operating position is reached with sealing arrangement of the replacement high-pressure seal 12 on the high-pressure piston 7.

[0123] In the embodiment of FIGS. 8 to 12, a double-acting drive piston 2 is provided. In this embodiment the compressor 1 has a further high-pressure piston 28 on the side of the drive piston 2 facing away from the high-pressure piston 7. The drive piston 2 drives both the high-pressure piston 7 and also the further high-pressure piston 28. In addition, a further magazine 29 is provided with a receiving element 30a for a further high-pressure seal 30 for sealing the further high-pressure piston 28 in a first operating state of the further magazine 29 and is provided with at least one further receiving element 31a for a further replacement high-pressure seal 31 for sealing the further high-pressure piston 28 in a second operating state of the further magazine 29. A further changeover device 32 is provided for transferring the further magazine 29 between the first operating position and the second operating position. The further magazine 29 and the further changeover device 32 can be configured identically to the magazine 10 or the changeover device 13 so that repetitions should be dispensed with.

[0124] FIGS. 13, 14 show a third embodiment of the compressor 1 in whichas in the second embodimenta double-acting drive piston 2 is provided with a further high-pressure piston 28. In this embodiment, furthermore a pressure chamber (space) 33 is formed between a first piston element 2a of the drive piston 2 and a second piston element 2b of the drive piston 2. The first piston element 2a and the second piston element 2b are connected to one another via a connecting rod 37. The pressure chamber 33 is connected to a pressure line 34 (only indicated schematically) in order to adjust the pressure in the pressure chamber 33. In the first operating position (cf. FIG. 14) a first higher pressure is provided in the pressure chamber 33. For transferring the magazine 10 into the first intermediate position a second lower pressure is set in the pressure chamber 33 so that the axial spacing between the first piston element 2a and the second piston element 2b is reduced compared with the first operating position. As a result, the high-pressure seal 11 slips from the high-pressure piston 7. The magazine 10 can then be brought into the second intermediate position. By raising the pressure in the pressure chamber 33 to the first pressure, the second operating position of the magazine 10 is reached in which the replacement high-pressure seal 12 is arranged sealingly on the high-pressure piston 7.

[0125] FIGS. 15, 16 show a fourth embodiment of the compressor 1. In this embodiment the receptacle 11a on the magazine 10 in the first operating position (cf. FIG. 15) is located in the empty state. When viewed in the axial direction, the high-pressure seal 11 is arranged outside the receptacle 11a of the magazine 10 in a circumferential recess 35 of a housing of the pressure converter between a free end region of the second cylinder 8 and an annularly circumferential pressure part 36.

[0126] For replacing the high-pressure seal 11 by the replacement high-pressure seal 12, the high-pressure seal 11 is initially received in the receptacle 11a on the magazine 10. For this purpose, the pressure part 36 is pushed away from the drive piston 2 by means of the changeover device 13 so that the high-pressure seal 11 bearing against the pressure part 36 is displaced together with the second cylinder 8 also in the axial direction. The pressure part 36 can be actuated pneumatically, for example. Optionally the high-pressure piston 7 must then be shifted into the suitable end position so that the high-pressure seal 11 is released from the high-pressure piston 7. The magazine 10 together with the replacement high-pressure seal 12 is then transferred into the second intermediate position in which the replacement high-pressure seal 12 is arranged in the recess 35 of the second cylinder 8. In the embodiment shown, thus is achieved by pivoting the magazine 10. Finally the replacement high-pressure seal 12 is pushed out axially from the further receptacle 12a by displacement of the second cylinder 8 by means of the changeover device, whereby the second operating position is reached.

[0127] In the fourth embodiment, the displacement of the high-pressure seal and the replacement high-pressure seal is preferably brought about by a displacement of the second cylinder 8 substantially in the direction of the central axis of the high-pressure piston.