COMPRESSOR, DISC BODY AND SEAL

Abstract

A compressor having a stationary part and a part oscillating along a main axis (X) as well as a leakage path (L) extending between the stationary part and the oscillating part in the axial direction, wherein multiple chambers, which are arranged axially in succession and extend annularly around the main axis (X), are defined between the stationary part and the oscillating part, wherein a seal, which closes or reduces the leakage path (L) is arranged in at least one chamber. The compressor has at least one bypass which fluidically interconnects two chambers.

Claims

1. A compressor, comprising: a stationary part, a part oscillating along a main axis (X), and a leakage path (L) extending between the stationary part and the oscillating part in the axial direction, wherein multiple chambers, which are arranged axially in succession and extend annularly around the main axis (X), are defined between the stationary part and the oscillating part, wherein a seal, which closes or reduces the leakage path (L), is arranged in at least one chamber, and wherein at least one bypass is provided, which fluidically interconnects two chambers.

2. The compressor according to claim 1, wherein the stationary part is a sleeve and the oscillating part is a piston, or wherein the stationary part is a packing housing and the oscillating part is a piston rod.

3. The compressor according to claim 1, wherein the bypass fluidically interconnects two immediately adjacent chambers.

4. The compressor according to claim 1, wherein the bypass comprises a minimum cross-section M<2 mm.sup.2.

5. The compressor according to claim 1, wherein the bypass is provided in the stationary part, or the oscillating part, or in the seal.

6. The compressor according to claim 1, wherein the bypass is provided in addition to the leakage path (L).

7. The compressor according to claim 2, wherein the bypass is formed from at least one bore.

8. The compressor according to claim 7, wherein the piston or the packing housing comprises multiple disc bodies, which are arranged axially in succession, wherein the disc bodies comprise a first axial surface and a second axial surface arranged opposite the disc body, as well as a radial surface, and wherein the bore extends between the first axial surface and the radial surface and/or between the first axial surface and the second axial surface.

9. The compressor according to claim 8, wherein at least portions of the bore extend parallel to the main axis (X).

10. The compressor according to claim 7, wherein the piston comprises a cylindrical core and a plurality of annular protrusions extending circumferentially around the core and in that at least portions of the bore extend through the core.

11. The compressor (10) according to claim 2, wherein the bypass (70, 70a,b,c,d) is provided in the region of the leakage path (L).

12. The compressor according to claim 11, wherein the bypass is a groove.

13. The compressor according to claim 12, wherein the piston or the packing housing comprises multiple disc bodies, which are arranged axially in succession, wherein the disc bodies comprise a sealing surface, and wherein the groove extends within the sealing surface.

14. The compressor according to claim 7, wherein a restrictor is arranged in the bore or in the groove, which restrictor defines a minimum cross-section M of the bypass.

15. The compressor according to claim 14, wherein the restrictor is a screw connection having an aperture plate, which is screwed into the bore, or in that the restrictor is an insert having an aperture plate, which is inserted into the groove.

16. The compressor according to claim 14, wherein the restrictor comprises a porous material.

17. The compressor according to claim 1 multiple bypasses are provided, wherein of two adjacent bypasses, the bypass that is arranged closer to a high-pressure side (H) of the compressor comprises a minimum cross-section M, which is smaller than or equal to the minimum cross-section M of the bypass, which is located closer to a low-pressure side (N) of the compressor.

18. A disc body designed for use in a compressor, comprising: a first axial surface and a second axial surface arranged opposite the disc body, as well as a radial surface, wherein a bypass extending between the first axial surface and the radial surface and/or between the first axial surface and the second axial surface.

19. The disc body according to claim 18, wherein the radial surface is an inner radial surface or an outer radial surface.

20. A disc body designed for use in a compressor, having an inner radial surface and an outer radial surface, wherein a bypass extending between the inner radial surface and an outer radial surface.

21. A seal designed for use in a compressor, having a first axial end surface, a second axial end surface, a radially inward surface, and a radially outward surface, wherein a bypass extending between at least two of the surfaces.

22. Use of a disc body according to claim 18, or of a seal having a first axial end surface, a radially inward surface, and a radially outward surface, wherein a bypass extending between at least two of the surfaces in a compressor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The invention is described and explained hereinafter by way of examples with reference to the drawings. Shown are:

[0040] FIG. 1 a detail of a first embodiment of a compressor in a sectional view;

[0041] FIG. 2 a detail of a second embodiment of a compressor in a sectional view;

[0042] FIG. 3 a detail of a third embodiment of a compressor in a sectional view;

[0043] FIG. 3A the detail A shown in FIG. 3;

[0044] FIG. 4 a support ring for a compressor in a perspective view;

[0045] FIG. 5 a detail of a fourth embodiment of a compressor in a sectional view;

[0046] FIG. 6 in detail, a disc body in a perspective view.

DETAILED DESCRIPTION OF THE INVENTION

[0047] The compressor 10 shown in the detail in FIG. 1 comprises a sleeve 120 as a stationary part 20 and a piston 130 as an oscillating part 30. The piston 130, when used as intended, oscillates along a main axis X relative to the sleeve 120 between a high-pressure side H and a low-pressure side N.

[0048] The sleeve 120 comprises a sliding surface 122, which is an inward cylindrical peripheral surface.

[0049] The piston 130 is what is referred to as a built piston 130. The piston 130 comprises multiple disc bodies 40, i.e., a base plate 132 and multiple piston discs 140 arranged axially in succession. The piston 130 is connected to a piston rod 230. Together with the base plate 132, the piston discs 140 form a piston body 150. The piston body 150 comprises a cylindrical core 152 and a plurality of annular protrusions 154 extending circumferentially around the core 152. A plurality of grooves 156 are formed between the protrusions 154, each groove 156 being formed by either two piston discs 140 or by a piston disc 140 and the base plate 132. The grooves 156 are partially sealed by the sleeve 120, thereby forming the piston body 150 and, along with the sleeve 120, multiple axially arranged, successive chambers 50 extending around the main axis in an annular manner. The sleeve 120 does not in this case contact the piston body 150. As a result, there remains an axial direction leakage path L between the sleeve 120 and the piston 130.

[0050] Leakage along the leakage path L is generally undesirable, but it usually cannot be completely avoided. However, leakage can be minimised. For this purpose, a seal 60 is arranged in each chamber 50, which seal closes or reduces the leakage path L. The illustrated embodiment relates to piston rings 160 in the seals 60, which are shown in a simplified manner in this case. Depending on the direction in which the piston 130 is moving at a given time, the piston rings 160 border either the high-pressure side or the low-pressure side flank of the grooves 156 and seal the leakage path L in that location.

[0051] In conventional sealing arrangements having piston rings 160, starting from the high-pressure side H, the dynamic pressure fraction at the first seal 60 and the static pressure fraction at the last seal 60 are reduced. To avoid this, three bypasses 70a,b,c are provided in addition to the leakage path L. Each bypass 70a,b,c fluidically interconnects two immediately adjacent chambers 50.

[0052] The bypasses 70a,b,c each comprise a bore 72 that extends parallel to the main axis X. In the illustrated embodiment, the bypasses 70a,b,c extend through the protrusions 154, i.e., from a first axial surface 182 of the piston disc 140 to a second axial surface 184 of the piston disc 140 arranged opposite. Each bore 72 thereby interconnects two adjacent chambers 50. The bores 72 are actually of a smaller diameter and are shown in an expanded manner in this case. Each piston disc 140 further comprises an outer radial surface 186.

[0053] The bypasses 70a,b,c provide the gases coming from the high-pressure side, in addition to the leakage path L, a way of flowing into the respective next chamber 50. In this way, the pressure difference between high-pressure side H and low-pressure side N is progressively and overall homogeneously reduced.

[0054] In the embodiment shown in detail in FIG. 2, the piston 30 comprises a one-piece piston body 150. The piston body 150 also comprises a cylindrical core 152 in this case, and a plurality of annular protrusions 154 extending circumferentially around the core 152. The design of sleeve 20, piston rod 230, and seals 60 is identical to the embodiment shown in FIG. 1.

[0055] The bypasses 70a,b,c are also formed in the embodiment shown in FIG. 2 by way of the bores 72. However, the bores 72 do not extend parallel to the main axis X. The bores 72 rather extend straight from the groove base of a groove 156 to the groove base of the adjacent groove 156. The bores 72 extend completely through the core 152 of the piston body 150. The bores in this case cross the main axis X. Adjacent chambers 50 are as a result also interconnected in this embodiment by way of the bores 72 so that a homogeneous pressure distribution over all of the seals 60 takes place.

[0056] FIG. 3 shows a detail of a compressor 10 having a packing housing 220 as a stationary part 20 and a piston rod 230 as an oscillating part 30. The piston rod 230 oscillates relative to the packing housing 220 along a main axis X between a high-pressure side H and a low pressure side N.

[0057] The packing housing 220 comprises multiple chamber discs 240 as a disc body 40, i.e., a base plate 222, a plurality of main chamber discs 223, a cover plate 224, and an end plate 226, which are arranged adjacent one another along the main axis X in said order. The chamber discs 240 each comprise a central bore. The piston rod 230 extends through the central bores. Each of two adjacent chamber discs 240 together form a groove 228 that is radially inwardly open.

[0058] The grooves 228 of the chamber discs 240 are partially sealed by the piston rod 230. In this way, the chamber discs 240 and the piston rod 230 form multiple chambers 50 arranged axially in succession and extending annularly around the main axis, wherein a leakage path L remains between the chamber discs 240 and the piston rod 230.

[0059] The chamber discs 240 each comprise a first axial surface 282 and a second axial surface 284 arranged opposite the piston disc 240, as well as an inner radial surface 286 (see FIG. 3A).

[0060] A seal 60 is arranged within four of the chambers 50. The seals 60 each comprise a support ring 262, a sealing ring 264, and a cover ring 266 (see FIG. 3A). The sealing ring 264 and the cover ring 266 are supported on the piston rod 230 by the garter springs 270. In other embodiments, the seals 60 can also be of a different construction and comprise more or fewer rings. The support ring 262 does not touch the piston rod 230 when used as intended, but is arranged at a radial distance from the piston rod 230. By means of the pressure coming from the high-pressure side H, the seal 60 is pressed against the chamber disc 240, which is situated closer to the low-pressure side N. The support ring 262 supports the seal 60 in the axial direction on the chamber disc 240.

[0061] The sealing ring 264 borders the piston rod 230 and thus seals on the leakage path L, therefore completely or partially closing the leakage path L.

[0062] In addition to the leakage path L, four bypasses 70a,b,c,d are provided, each fluidically connecting two adjacent chambers 50 (see FIG. 3). The bypasses 70a,b,c,d are formed from bores 72 (see FIG. 3A). The bores 72 extend between the first axial surface 282 and the inner radial surface 286, thereby connecting the adjacent chambers 50.

[0063] Arranged in each of the bores 72 is a restrictor 74 in the form of a screw connection having an aperture plate 76, which is screwed into the bore 72. The aperture plate 76 comprises a hole that defines the minimum cross-section of the respective bypass 70a,b,c,d. Starting from the high-pressure side H, the holes of the aperture plates 76 of the bypasses 70a,b,c,d have a diameter of 0.4 mm, 0.4 mm, 0.5 mm and 0.6 mm. The minimum cross-section from bypass 70a,b,c,d to bypass 70a,b,c,d thus always gets smaller or stays the same towards the high-pressure side H.

[0064] For example, the support ring 262 shown in FIG. 4 can be inserted into a piston housing 220 shown in FIG. 3. The support ring 262 comprises a first axial end surface 272, a second axial end surface 274 arranged opposite, a radially inward surface 276, and a radially outward surface 278.

[0065] The support ring 262 further comprises a bypass 70 in the form of a bore 72. The bore 72 extends radially from the radially inward surface 276 to the radially outward surface 278. When used as intended, as mentioned above, the radially inward surface 276 of the support ring 262 does not border the piston rod 230. Nor does the support ring 262 border the radially outward surface 278 on the packing housing 220. In this way, the bypass 70 of the support ring 262 also connects two adjacent chambers 50 (see FIG. 3A).

[0066] FIG. 5 shows a detail of a compressor 10, which is partially identical to the compressor 10 shown in FIG. 3. The compressor 10 comprises a packing housing 220 as a stationary part 20 and a piston rod 230 as an oscillating part 30. The piston rod 230 oscillates relative to the packing housing 220 along a main axis X between a high-pressure side H and a low-pressure side N.

[0067] The packing housing 220 comprises multiple chamber discs 240 as a disc body 40, i.e., a base plate 222, multiple main chamber discs 223, a cover plate 224, and an end plate 226, which are arranged adjacent one another along the main axis X in said order. The chamber discs 240 each comprise a central bore. The piston rod 230 extends through the central bores. Each of two adjacent chamber discs 240 together form a groove 228 that is radially inwardly open.

[0068] The grooves 228 of the chamber discs 240 are partially sealed by the piston rod 230. In this way, the chamber discs 240 and the piston rod 230 form multiple chambers 50 arranged axially in succession and extending annularly around the main axis, wherein a leakage path L remains between the chamber discs 240 and the piston rod 230.

[0069] The chamber discs 240 each comprise a first axial surface 282 and a second axial surface 284 arranged opposite the piston disc 240, as well as an inner radial surface 286.

[0070] A seal 60 is arranged within four of the chambers 50. The seals 60 each comprise a support ring 262, a sealing ring 264, and a cover ring 266 (see FIG. 3A). The sealing ring 264 and the cover ring 266 are supported on the piston rod 230 by the garter springs 270. In other embodiments, the seals 60 can also be of a different construction and comprise more or fewer rings. The support ring 262 does not touch the piston rod 230 when used as intended, but is arranged at a radial distance from the piston rod 230. The pressure coming from the high-pressure side H forces the seal 60 against the first axial surface 282 of the chamber disc 240. The first axial surface 282 thereby forms a sealing surface 288. The support ring 262 supports the seal 60 in the axial direction on the chamber disc 240.

[0071] The sealing ring 264 borders the piston rod 230 and thus seals on the leakage path L, therefore completely or partially closing the leakage path L.

[0072] Provided in the region of the leakage path L is a bypass 70 in the form of a groove 78, which fluidically interconnects two adjacent chambers 50. The groove 78 extends within the first axial surface 282, which is simultaneously the sealing surface 288. In this case, the groove 78 extends in the radial direction completely through the sealing surface 288. Even if the entire surface of the seal 60 borders the sealing surface 288, the groove 78 remains open in this manner and forms a bypass 70.

[0073] The disc body 40 shown in FIG. 6 is a chamber disc 240 for a compressor (not shown in detail). The chamber disc 240 is similar in structure to the chamber disc 240 shown in FIG. 5.

[0074] The chamber disc 240 comprises a central bore enclosed by an inner radial surface 286. The chamber disc 240 further comprises a first axial surface 282 that is simultaneously a sealing surface 288 for a seal not shown. When used as intended, the seal borders the sealing surface 288.

[0075] The sealing surface 288 is arranged on an axial protrusion of the chamber disc 240. The axial protrusion comprises an outer radial surface 186.

[0076] The chamber disc 240 comprises a bypass 70 in the form of a groove 78. The groove 78 extends from the outer radial surface 186 to the inner radial surface 286. If the seal is adjacent the sealing surface 288, then gas can still flow past the seal and through the bypass 70. The size of the bypass 70 is predetermined, thereby achieving a targeted leakage.

[0077] The groove 78 extends in the radial direction, i.e., perpendicular to a main axis of the chamber disc 240.

LIST OF REFERENCE CHARACTERS

[0078] 10 Compressor [0079] 20 Stationary part [0080] 30 Oscillating part [0081] 40 Disc body [0082] 50 Chamber [0083] 60 Seal [0084] 70 Bypass [0085] 70a Bypass [0086] 70b Bypass [0087] 70c Bypass [0088] 70d Bypass [0089] 72 Bore [0090] 74 Restrictor [0091] 76 Aperture plate [0092] 78 Groove [0093] 120 Sleeve [0094] 122 Sliding surface [0095] 130 Piston [0096] 132 Base plate [0097] 140 Piston disc [0098] 150 Piston body [0099] 152 Core [0100] 154 Protrusions [0101] 156 Groove [0102] 160 Piston ring [0103] 182 First axial surface [0104] 184 Second axial surface [0105] 186 Outer radial surface [0106] 220 Packing housing [0107] 222 Base plate [0108] 223 Main chamber disc [0109] 224 Cover plate [0110] 226 End plate [0111] 228 Groove [0112] 230 Piston rod [0113] 240 Chamber disc [0114] 262 Support ring [0115] 264 Sealing ring [0116] 266 Cover ring [0117] 270 Garter spring [0118] 272 First axial end surface [0119] 274 Second axial end surface [0120] 276 Radially inward surface [0121] 278 Radially outward surface [0122] 282 First axial surface [0123] 284 Second axial surface [0124] 286 Inner radial surface [0125] 288 Sealing surface [0126] H High-pressure side [0127] N Low-pressure side [0128] L Leakage path [0129] X Main axis