Piston compressor

Abstract

The invention relates to a piston compressor (1) for compressing a gas, comprising at least one cylinder (6), at least one piston (5) which is supported in each cylinder (6) such that each piston (5) and each cylinder (6) delimit a compression chamber (29) for compressing a gas, an inlet valve (19) for each compression chamber (29), an outlet valve (20) for each compression chamber (29), at least one mechanical device (40) with which the at least one piston (5) is in mechanical action connection for the reciprocating movement of the at least one piston (5), at least one lubrication chamber (44) in which the at least one mechanical device (40) is arranged at least partially and in which the at least one mechanical device (40) can be lubricated with a lubricant, at least one diaphragm (34) and by means of which each lubrication chamber (44) is separated from each compression chamber (29), wherein the at least one diaphragm (34) is fixed on at least one fastening element (49) and the at least one fastening element (49) is fixed on the rest of the piston compressor (1) by means of each clamping connection.

Description

Technical Field

[0001] The present invention relates to a piston compressor as described in the preamble of claim 1. Background Technology

[0002] Piston compressors are used in various technical applications to compress gases. In a piston compressor, a piston performs a reciprocating motion. The piston is supported in a cylinder. An inlet valve is used to introduce gas into the compression chamber, and an outlet valve is used to discharge gas from the compression chamber. The compression chamber is defined by the surface of the cylinder head at the end opposite the piston. The inlet and outlet valves are usually integrated into the cylinder head. The reciprocating motion of the piston is achieved by a mechanical device. This mechanical device is constructed, for example, as a crank-driven mechanism with a crankshaft and connecting rod, or as a roller shoe with working rollers and a drive shaft with at least one cam. This mechanical device is arranged in a lubrication chamber. The lubrication chamber is loaded with a lubricant, such as lubricating oil, to lubricate the moving parts of the mechanical device. This mechanical device is driven, for example, by an electric motor. The piston performs a reciprocating motion between the top dead center (TDC) and bottom dead center (BDC) of the piston, and the volume difference of the compression chamber between the TDC and BDC defines the stroke volume. The clearance volume (Totvolumen) of the compression chamber is the volume of the compression chamber at the top dead center of the piston.

[0003] Certain technical applications involving compressed gases require the supply of compressed gases with high purity. The seal between the cylinder and the piston with piston rings is not a complete gap seal, allowing lubricant to enter the compression chamber of the reciprocating compressor from the lubrication chamber, thus contaminating the compressed gas. To prevent this undesirable and unavoidable contamination of the compressed gas, it is known to create an additional space between the compression chamber and / or the space with the piston and the lubrication chamber, and to provide, for example, a suction device for this space. However, this is disadvantageously very complex, resulting in high manufacturing costs and large structural space for the reciprocating compressor. Furthermore, diaphragm compressors are also known, but these have a small delivery volume per unit volume of structural space.

[0004] EP 0 541 482 B1 illustrates a reciprocating compressor for oil-free gas compression, having at least one cylinder and a piston guided therein, the piston having at least one slit, so-called trapping piston ring disposed in an annular groove on the piston, the piston ring defining a pressure-loaded space of the annular groove in the compression chamber by its outer peripheral surface opposite to the inner surface of the cylinder, and from the outer peripheral surface having two radially parallel limiting interfaces, wherein the face facing the compression chamber extends over a portion of the radial ring width, wherein the piston ring is slidably guided by its two parallel limiting interfaces on corresponding faces of the annular groove, wherein the remaining face of the piston ring facing the compression chamber, originating from the outer peripheral surface facing the inner surface of the cylinder, is configured as a wedge-shaped face, the wedge-shaped face extending to the limiting interface at an angle of 5° to 15° to a line parallel to the limiting interface facing the compression chamber.

[0005] DE 2020699 A1 discloses an immersion piston compressor having a single-stage or multi-stage piston and / or cylinder, wherein at least one bellows is generally arranged as at least one diaphragm between each piston and the crankcase. The bellows, secured to the rest of the immersion piston compressor by means of an intermediate piece, disadvantageously cannot ensure a completely sealed isolation between the crankcase and the compression chamber, and the assembly and disassembly of the bellows are inconvenient. Summary of the Invention

[0006] A reciprocating compressor for compressing gases according to the present invention includes at least one cylinder, at least one piston supported in each cylinder such that each piston and each cylinder defines a compression chamber for compressing gases, an inlet valve for each compression chamber, an outlet valve for each compression chamber, at least one mechanical device mechanically operatively connected to the at least one piston for reciprocating motion of the at least one piston, at least one lubrication chamber, the at least one mechanical device being at least partially arranged in the lubrication chamber and capable of being lubricated with a lubricant in the at least one lubrication chamber, and at least one diaphragm separating each lubrication chamber from each compression chamber by means of the at least one diaphragm, wherein the at least one diaphragm is fixed to at least one fastening element, and the at least one fastening element is fixed to the remainder of the reciprocating compressor by means of each clamping connection. Thus, the at least one diaphragm can be easily removed from the remainder of the reciprocating compressor by loosening the clamping connection. Therefore, each clamping connection, together with the two fastening members, constitutes a fastening device for indirectly fixing and securing the at least one diaphragm.

[0007] In another embodiment, each clamping connection is formed between two fastening members of the reciprocating compressor. The fastening members are components or parts of the reciprocating compressor, and the clamping connection for fastening the elements is formed between them. Thus, the clamping connection is formed between the two fastening members by pressure from the preload of the fastening elements, particularly a preload oriented in the axial direction. The clamping connection is a force-locking connection, preferably a form-locking connection.

[0008] In a supplementary embodiment, the two fastening members for each of the clamping connections are constructed to completely surround each of the longitudinal axes of the cylinder in the tangential direction. This allows for reliable force-locking fixation of the at least one fastening element.

[0009] In an additional variation, a seal is constructed tangentially around the two components, particularly between the two fastening components used for the clamping connection, for sealing the gap between the two components, particularly between the two fastening components, in a fluid-tight manner relative to the surrounding environment.

[0010] In a supplementary configuration, in each of the components, especially in each of the fastening components for the clamping connection, a groove is constructed to completely surround the component in the tangential direction, and the seal is arranged at least partially, especially completely, in the groove.

[0011] In an additional variation, the at least one fastening member is formed by a cylinder housing and / or a flange and / or a housing for the lubrication chamber and / or a piston and / or a portion of the piston. The diaphragm is preferably indirectly secured to the remainder of the reciprocating compressor by means of a fastening element at the upper end or upper end region and / or the lower end or lower end region.

[0012] In a supplementary embodiment, the at least one fastening element is constructed in a ring shape, particularly as a fastening ring.

[0013] In another configuration, the at least one fastening element is constructed to completely surround one of the longitudinal axes of the cylinder in the tangential direction. This allows for a sealed isolation between the at least one lubrication chamber and the at least one compression chamber.

[0014] In particular, the axial extension dimension of the at least one fastening element is substantially constant, especially with a deviation of less than 30%, 20% or 10%.

[0015] In another variation, the at least one diaphragm is fixed to the at least one fastening element as a sealing device by means of a fluid-sealed material locking connection, particularly a welded connection and / or an adhesive connection, for tightly isolating each lubrication chamber from each compression chamber.

[0016] In a supplementary embodiment, at least one material locking connection between the at least one diaphragm and the at least one fastening element is constructed to completely surround one of the longitudinal axes of the cylinder in the tangential direction.

[0017] In accordance with the destination, the at least one diaphragm structure is at least one bellows.

[0018] In another embodiment, the mechanical device includes a shaft having at least one cam, and the at least one piston is indirectly supported on the shaft having at least one cam by means of roller shoes and working rollers. Accordingly, the shaft having at least one cam is an eccentric shaft.

[0019] Preferably, the stroke height of each piston between its top dead center and bottom dead center is less than 30%, 10%, 5%, or 3% of the extension dimension of the at least one diaphragm, and in particular the at least one bellows, in the longitudinal axis direction of the cylinder related to the stroke movement. Thus, the mechanical load on the diaphragm in the extension dimension related to the stroke movement is small during the reciprocating motion of the piston, resulting in a long service life for the at least one diaphragm.

[0020] In an additional variation, the clearance volume (Totvolumen) of each compression chamber is less than 10%, 5%, 3%, or 2% of the stroke volume of each compression chamber. Advantageously, the reciprocating compressor can thus achieve high pressure of the gas to be compressed at a small piston stroke height by means of a shaft having at least one cam and a mechanical device including working rollers.

[0021] In another embodiment, the number of corrugations in the bellows is greater than 5, 10, 30, 50, 100, or 200.

[0022] In another embodiment, the at least one sealing ring and / or the at least one fastening ring has any shape in a cross section perpendicular to the longitudinal axis of the cylinder, particularly circular or rectangular, especially square, or elliptical.

[0023] In a supplementary variation, the at least one diaphragm radially, particularly fluid-tightly, divides each of the cylinder portion chambers between the piston and the mechanical device into an internal diaphragm space and an external diaphragm space. Each cylinder and a housing, preferably for lubrication, define one cylinder chamber, in which the piston is arranged, and each cylinder chamber is further divided by the piston into a first cylinder portion chamber and a second cylinder portion chamber, the first cylinder portion chamber serving as a compression chamber. The diaphragm is arranged in each of the second cylinder portion chambers.

[0024] In one additional configuration, one piston rod is arranged inside the diaphragm space.

[0025] In another embodiment, the radial extension dimension of the at least one fastening element is significantly larger than the axial extension dimension of the at least one fastening element, especially larger than 2, 3 or 5 times the axial extension dimension of the at least one fastening element.

[0026] Preferably, the at least one diaphragm, and in particular the at least one bellows, is indirectly fixed to the remainder of the reciprocating compressor by means of at least one sealing ring. Preferably, the remainder of the compressor is formed by a cylinder housing and / or cylinder head and / or a housing for the mechanical device and / or flanges and / or a piston and / or a portion of the piston. Preferably, the sealing ring is made of metal and / or plastic. The sealing ring, made of metal and plastic, is fixed, for example, by welding its metal side to the remainder of the reciprocating compressor, preferably the piston, and the other plastic side of the sealing ring is fixed to the plastic diaphragm by welding.

[0027] Suitable for the destination, the fastening elements are made of metal and / or plastic.

[0028] In a supplementary configuration, the at least one diaphragm, and in particular the at least one bellows, is arranged at least partially, and in particular completely, between the piston and the mechanical device in the longitudinal axis direction of the cylinder.

[0029] In another embodiment, the at least one diaphragm, and in particular the at least one bellows, is constructed in a substantially cylindrical shell shape, especially in the region inside the at least one cylinder.

[0030] In a supplementary variation, the at least one piston is mechanically connected to a mechanical device via a piston rod.

[0031] To meet the requirements, a flange plate is arranged between each cylinder and the mechanical device, along the longitudinal axis of each cylinder.

[0032] In an additional configuration, the at least one diaphragm, in particular the at least one bellows material, is locked in place, in particular by means of at least one welded connection, as a sealing device and / or fastening device, indirectly or directly fixed to the at least one piston.

[0033] In a supplementary variation, the at least one diaphragm, and in particular the at least one bellows, is indirectly and material-locked to the at least one piston by means of at least one sealing ring.

[0034] In particular, the radial extension dimension of the at least one fastening element is substantially constant, especially with a deviation of less than 30%, 20% or 10%.

[0035] In accordance with the destination, the at least one cylinder includes at least one cylinder head.

[0036] In an additional embodiment, the working roller comprises a cylindrical shell-shaped working roller with a central bore, in which a bearing pin is arranged. An annular gap is formed between the cylindrical shell-shaped working roller and the bearing pin, and this annular gap is lubricated with a lubricant. The axial end of the bearing pin is supported in a roller shoe, for example, by a sliding bearing.

[0037] In a supplementary variation, the material locking connection is constructed as a welded connection and / or an adhesive connection.

[0038] Preferably, the at least one welded joint is manufactured by laser welding. Welded joints manufactured by laser welding can be easily distinguished from welded joints manufactured by other methods due to the characteristics of the structural design, such as the diameter of the weld and / or the geometry of the weld on the welded components.

[0039] In an additional embodiment, the facet or axial extension dimension of the at least one diaphragm is greater than 5, 10, 20, or 30 times the thickness of the at least one diaphragm. Therefore, the facet or axial extension dimension of the at least one diaphragm is significantly greater than the thickness of the diaphragm.

[0040] In an additional embodiment, the diaphragm is made of metal and / or plastic. Preferably, the plastic construction of the diaphragm is an elastomer. The diaphragm is flexible to withstand the reciprocating motion of the piston. Preferably, the diaphragm consists of multiple layers, particularly layers made of different materials such as metal and / or plastic. A layer, for example a thin layer made of metal such as aluminum foil, reduces the permeation of substances through the diaphragm. The diaphragm has a very small permeability coefficient, especially for lubricants. Q = P * F * t * Δp / d. Where Q is the amount of gas or vapor passing through a layer of area F and thickness d in time t, when the pressure difference of the permeate before and after the layer is Δp. The oxygen permeability of the diaphragm (in cm⁻¹) is... 3 / m 2The hydrogen permeability of the membrane (in *d*bar) is preferably less than 30, 10, 1, or 0.1. 3 / m 2 (Using *d*bar as the unit) preferably less than 50, 10, 1 or 0.2.

[0041] In another embodiment, the cylinder has a longitudinal axis. The longitudinal axis of the cylinder corresponds to the direction of movement of the piston supported in the cylinder.

[0042] To meet the requirements of the destination, the mechanical device consists of a roller shoe with working rollers and a drive shaft with cams.

[0043] In another embodiment, the mechanical device consists of a crankshaft and a connecting rod that serves as a piston rod.

[0044] In an additional variant, the reciprocating compressor includes an electric motor for driving the reciprocating compressor. For example, the electric motor drives a drive shaft with cams and / or a crankshaft.

[0045] The pressure that can be generated by a reciprocating compressor is in the range of 100 bar to 1000 bar. Attached Figure Description

[0046] Embodiments of the present invention will now be described in more detail with reference to the accompanying drawings. The drawings show: Figure 1 Cross-section of a reciprocating compressor used for compressing gases. Figure 2 According to the working rollers and drive shaft with roller shoes Figure 1 AA section; and Figure 3 :according to Figure 1 An enlarged partial cross-sectional view of a piston compressor. Detailed Implementation

[0047] exist Figure 1 The diagram shows a cross-section of a reciprocating compressor 1 for compressing gas according to a first embodiment. The reciprocating compressor 1 is used to compress gas, such as hydrogen or air, under high pressure. The pressure that the reciprocating compressor 1 can generate is, for example, between 100 bar and 1000 bar.

[0048] The reciprocating compressor 1 includes a drive shaft 2 with two cams 3, which rotates about a rotation axis 26. The drive shaft 2 is driven by an electric motor (not shown). The rotation axis 26 is located at... Figure 1 Within the drawing plane and perpendicular to Figure 2The drawing plane. Piston 5 is supported in cylinder 6, which is formed by cylinder housing 8. A completely circumferential annular groove 15 is constructed on the radially outer side of piston 5. A piston ring 16 is arranged in the annular groove 15. Compression chamber 29 is limited by cylinder housing 8, cylinder head 17, and piston 5. End 18 of cylinder head 17 is the surface part of cylinder head 17 that limits compression chamber 29 and does not function as part of cylinder 6. Inlet passage 22 with inlet valve 19 and outlet passage 24 with outlet valve 20 lead to compression chamber 29. Gas flows into compression chamber 29 through inlet passage 22 with inlet opening 21, and gas under high pressure flows out of compression chamber 29 through outlet passage 24 with outlet opening 23. Inlet valve 19, for example, check valve, is configured such that only gas flows into compression chamber 29, and outlet valve 20, for example, check valve, is configured such that only gas flows out of compression chamber 29. The volume of the compression chamber 29 changes due to the reciprocating stroke of the piston 5. The piston 5 is indirectly supported on the drive shaft 2 by means of the piston rod 14. A roller shoe 9 with working rollers 10 is fixed to the end of the piston rod 14. The working rollers 10 can rotate here, and their axis of rotation 25 is located at... Figure 1 The drawing plane shown is in and perpendicular to Figure 2 The drawing plane. The drive shaft 2 having at least one cam 3 has a shaft-rolling surface 4, and the working roller 10 has a roller-rolling surface 11.

[0049] The roller-rolling surface 11 of the working roller 10 rolls at the contact surface 12 on the shaft-rolling surface 4 of the drive shaft 2, which has two cams 3. The roller shoe 9 is supported in a roller shoe bearing formed by the cylinder housing 8, which acts as a sliding bearing. A spring 27, i.e., a coil spring 27, acts as an elastic element 28 (clamped between the cylinder housing 8 and the roller shoe 9) and applies pressure to the roller shoe 9, ensuring that the roller-rolling surface 11 of the working roller 10 remains in contact with the shaft-rolling surface 4 of the drive shaft 2. The roller shoe 9 and the piston 5 thus perform a reciprocating stroke together. The working roller 10 is supported in the roller shoe 9 by a sliding bearing 13. Therefore, the roller shoe 9 with the working roller 10 and the drive shaft 2 with the cams 3 function as a mechanical device 40 for generating the reciprocating motion of the piston 5.

[0050] Inlet valve 19 and outlet valve 20 are mounted or integrated in cylinder head 17. Cylinder head 17 is a component of cylinder 6 or cylinder housing 8. Cylinder head 17 is fixed to cylinder 6 by fixing element 38 as screw 39, and therefore also fixed to cylinder housing 8. A portion of surface 18 of cylinder head 17 forms surface 18 or end 18 of limiting compression chamber 29. Inlet valve 19 includes valve piston 30, elastic element 35 as spring 36, and support element 37 for spring 36. In the closed position, valve piston 30 is fluid-tightly positioned on valve seal seat 32 that surrounds it completely in the tangential direction. Figure 1 The outlet valve 20 similarly includes a valve piston 31 for the outlet valve 20, an elastic element 35 as a spring 36, and a support element 37 for the spring 36. Figure 1 The spring 36 of the outlet valve 20 rests on the valve seat 33 in the closed position of the outlet valve 20. The valve seat 32 for the inlet valve 19 and the valve seat 33 for the outlet valve 20 are configured here to correspond to the geometry constructed on the cylinder head 17. The inlet valve 19 and the outlet valve 20 are pneumatically actuated with valve pistons 30 and 31. Due to the pressure change in the compression chamber 29 during the reciprocating motion of the piston 5, the inlet valve 19 opens and the outlet valve 20 closes during the increase in volume of the compression chamber 29, and vice versa during the decrease in volume of the compression chamber 29 during the reciprocating motion of the piston 5.

[0051] Piston 5 is supported in cylinder 6 and performs reciprocating translational motion along the longitudinal axis 41 of cylinder 6. Mechanical device 40 is arranged in lubrication chamber 44, which is defined by a housing 45 (partially shown) for both mechanical device 40 and lubrication chamber 44. In the enclosed lubrication chamber 44, mechanical device 40 is lubricated with a lubricant, such as lubricating oil or fuel. Lubrication is necessary because the bearings of the moving parts are implemented as sliding bearings. Piston compressor 1 compresses, for example, hydrogen for fuel cells or compressed air or oxygen for breathing in compression chamber 29. Therefore, the gas to be compressed must not be contaminated by lubricant from lubrication chamber 44, even by a very small amount. The radially outer side of piston 5, supported on cylinder 6 by piston rings 16, does not provide complete and tight isolation between lubrication chamber 44 and compression chamber 29 containing the gas to be compressed.

[0052] For this reason, the lubrication chamber 44 is tightly and completely fluid-tightly isolated and sealed from the compression chamber 29 by a diaphragm 34, which serves as a bellows 34. The cylinder 6, which serves as a cylinder housing 8 with a cylinder head 17, and the housing 45 for the lubrication chamber 44 define a cylinder chamber. This cylinder chamber is divided by the piston 5 into a first cylinder portion chamber and a second cylinder portion chamber, which serve as the compression chamber 29. The diaphragm 34 fluid-tightly divides the second cylinder portion chamber in the radial direction 57 into an internal diaphragm space 59 and an external diaphragm space 60. The bellows 34, serving as the diaphragm 34, is made of metal and / or plastic. The plastic is particularly an elastomer. The surface or axial extension dimension of the diaphragm 34 is significantly greater than its thickness. An annular flange 43 is arranged between the cylinder housing 8 and the housing 45 for the mechanical device 40, along the longitudinal axis 41 of the cylinder 6. The lower end region of the bellows 34, which serves as the diaphragm 34, is fixed to an annular fastening element 49, made of metal and serving as a fastening ring 47, by a material locking connection 52, which serves as a welded connection 53. The welded connection 53 is preferably manufactured by laser welding. The welded connection 53 is constructed to completely surround the bellows 34 and the annular fastening element 49 in the tangential or circumferential direction 58. Therefore, the welded connection 53, which serves as the material locking connection 52, is fluid-tightly constructed to tightly isolate the lubrication chamber 44 from the compression chamber 29. The material locking connection 52 also fluid-tightly seals the diaphragm interior space 59 containing lubricating oil from the diaphragm exterior space 60. The piston rod 14 is supported in a bearing bushing with a sliding support portion, and due to the gap between the bearing bushing and the piston rod 14, lubricating oil flows from the lubrication chamber 44 into the diaphragm interior space 59. The bearing bushing is fixed to the housing 45. Therefore, the material locking connection 52 also constitutes a sealing device 42 and a fastening device 47. The axial direction 56 is oriented along the longitudinal axis 41 of the cylinder 6. The radial direction 57 is oriented perpendicular to the longitudinal axis 41. The extension dimension (as diameter) of the annular fastening element 49 in the radial direction 57 is significantly larger than its extension dimension in the axial direction 56. The extension dimension of the fastening element 49 in the axial direction 56 corresponds to the thickness of the fastening element 49. The annular fastening element 49, as a fastening ring 47, is locked and fixed between the cylinder housing 8 and the flange plate 43 by means of axial pressure as a clamping connection. Therefore, the cylinder housing 8 and the flange plate 43 constitute a fastening member 50 for locking and fixing the fastening element 49 by means of pressure as a clamping connection force. Furthermore, the fastening element 49 is form-fitted and fixed to the cylinder housing 8, the flange plate 43, and the housing 45 for the mechanical device 40 due to the geometry of the fastening element 49, the cylinder housing 8, the flange plate 43, and the housing 45 for the mechanical device 40.

[0053] The flange 43 is tightened onto the housing 45 of the mechanical device 40 by means of a fixing element 38, which is a screw 39. Furthermore, due to the geometry of the reciprocating compressor 1, lubricant and / or the gas to be compressed will flow along the gap 51 ( Figure 3 The flow proceeds radially outward from the inner space 59 and / or outer space 60 of the diaphragm. A gap 51 is formed initially between the fastening element 49 and the flange plate 43, and between the fastening element 49 and the cylinder housing 8, and subsequently between the cylinder housing 8 and the flange plate 43, and between the flange plate 43 and the housing 45. Therefore, a groove 55 is constructed in the cylinder housing 8. A seal 54 is arranged in the groove 55. Figure 1 and Figure 3 The seal 54 and the groove 55 are constructed to completely surround the cylinder housing 8 in the tangential or circumferential direction 58. The seal 54 is sized such that it is pre-tightened by pressure in the axial direction 56 between the groove 55 on the cylinder housing 8 and the flange plate 43. Similarly, a groove 55 with the seal 54 is also constructed in the housing 45, and the seal 54 is positioned on the flange plate 43.

[0054] The bellows 34 is indirectly fluid-tightly fixed at its upper end to the lower end of the piston 5 in the region having the annular groove 15 via a sealing ring 46. The diaphragm 34 is fluid-tightly connected at its upper end to the lower end of the sealing ring 46 via a sealing device 42, which serves as a fastening device 47. The sealing device 42 and fastening device 47 between the sealing ring 46 and the diaphragm 34 are formed by a material locking connection, particularly a welded connection and / or an adhesive connection. The welded connection is manufactured, for example, by laser welding. Similarly, the upper end of the sealing ring 46 is fixed to the lower end of the piston 5. The sealing device 42 and fastening device 47 between the sealing ring 46 and the piston 5 are formed by a material locking connection, particularly a welded connection and / or an adhesive connection.

[0055] In another embodiment (not shown), the bellows 34, which serves as the diaphragm 34, is also fixed to the piston 5 at its upper end by a fastening element 49 in a manner similar to that at its lower end. For this purpose, the piston 5 is constructed, for example, as a two-piece unit, or the fastening element 49 is fixed between the lower end of the piston 5 and the annular compression ring by a clamping connection. The compression ring, extending entirely in the tangential direction 58, is fixed to the piston 5, for example, by a releasable fixing element 38, which serves as a screw 39. Furthermore, a seal (not shown) extending entirely in the tangential direction 58 exists between the piston 5 and the compression ring.

[0056] The axial extension dimension 48 of the bellows 34 along the longitudinal axis 41, i.e., the area of ​​the piston 5's stroke movement between top dead center and bottom dead center, is significantly larger than the stroke height of the piston 5, i.e., the difference between the top dead center and bottom dead center of the piston 5. The extension dimension 48 is, for example, 10 cm, while the stroke height of the piston 5 is 0.9 cm. Figure 1In this drawing, due to drawing requirements, the extension dimension 48 and the stroke height of the piston 5 are not drawn to scale. Therefore, the mechanical load on the deformation of the diaphragm 34 is relatively small, as the bellows 34 undergoes only a small deformation per unit length of the extension dimension 48. Thus, the diaphragm 34 can be constructed not only as a bellows 34 in this relevant region having the extension dimension 48, but also as a simple, fold-free diaphragm. Because the deformation of the diaphragm 34 in this relevant region having the extension dimension 48 is very small, the service life of the diaphragm 34 corresponds at least to the service life of the rest of the reciprocating compressor 1.

[0057] Overall, the reciprocating compressor 1 according to the invention has significant advantages. The diaphragm 34, serving as a bellows 34, enables complete and tight isolation between the lubrication chamber 44 containing lubricant and the compression chamber 29. The bellows 34 is fixed at its lower end to an annular fastening element 49 by a material-locking connection 52. Therefore, when disassembling the reciprocating compressor 1, the cylinder head 17, cylinder housing 8, flange plate 43, and housing 45 for the mechanical device 40 can be removed by opening or loosening the fastening element 38, which serves as a screw 39. During this disassembly, the clamping connection between the flange plate 43 and the cylinder housing 8 for the fastening element 49 is released, thereby allowing the bellows 34 to be easily removed from and replaced by the reciprocating compressor 1. This, in turn, also applies to the assembly of the reciprocating compressor and the tightening of the screws 39. Therefore, the reciprocating compressor 1 can compress gases requiring high purity, such as hydrogen or oxygen. The lower additional cost of constructing the diaphragm 34 in the reciprocating compressor 1 makes the reciprocating compressor 1 advantageously inexpensive to manufacture and requires minimal structural space. Compared to diaphragm compressors, reciprocating compressors have a significantly larger conveying volume per unit volume of structural space.

Claims

1. A reciprocating compressor (1) for compressing gas, comprising: - At least one cylinder (6). - At least one piston (5) supported in each of a cylinders (6), such that each piston (5) and each cylinder (6) defines a compression chamber (29) for compressing gas. - Inlet valve (19) for each of the compression chambers (29). - Outlet valve (20) for each of the compression chambers (29). - At least one mechanical device (40), wherein the at least one piston (5) is mechanically connected to the at least one mechanical device for the reciprocating motion of the at least one piston (5). - At least one lubrication chamber (44), in which at least one mechanical device (40) is at least partially disposed, and in which at least one mechanical device (40) is capable of being lubricated with a lubricant. - At least one diaphragm (34), and by means of said at least one diaphragm (34) separating each lubrication chamber (44) from each compression chamber (29), Its features are, The at least one diaphragm (34) is fixed to at least one fastening element (49), and the at least one fastening element (49) is fixed to the rest of the piston compressor (1) by means of a clamping connection.

2. The reciprocating compressor according to claim 1, Its features are, Each clamping connection is formed between each of the two fastening members (50) of the piston compressor (1).

3. The piston compressor according to claim 1 or 2, Its features are, The two fastening members (50) for each of the clamping connections are constructed to completely surround each of the longitudinal axes (41) of the cylinder (6) in the tangential direction (58).

4. The reciprocating compressor according to one or more of the preceding claims, Its features are, Between the two components (8, 17, 43, 45, 50), especially between the two fastening components (50) for each of the clamping connections, a seal (54) is constructed in a completely circumferential direction (58) for sealing the gap (51) between the two components (8, 17, 43, 45, 50), especially between the two fastening components (50), in a fluid-tight manner relative to the surrounding environment.

5. The piston compressor according to claim 4, Its features are, In each of the components (8, 17, 43, 45), especially in each of the fastening components (50) for the clamping connection, a groove (55) is constructed to completely surround the connection in the tangential direction (58), and the seal (54) is arranged at least partially, especially completely, in the groove (55).

6. The reciprocating compressor according to one or more of the preceding claims, Its features are, The at least one fastening member (50) is formed by the cylinder housing (8) and / or the flange plate (43) and / or the housing (45) for the lubrication chamber (44) and / or the piston (5) and / or a part of the piston (5).

7. The reciprocating compressor according to one or more of the preceding claims, Its features are, The at least one fastening element (49) is constructed in a ring shape.

8. The reciprocating compressor according to one or more of the preceding claims, Its features are, The at least one fastening element (49) is constructed to completely surround one of the longitudinal axes (41) of the cylinder (6) in the tangential direction (58).

9. The reciprocating compressor according to one or more of the preceding claims, Its features are, The axial extension dimension of the at least one fastening element (49) is substantially constant.

10. The reciprocating compressor according to one or more of the preceding claims, Its features are, The at least one diaphragm (34) is fixed to the at least one fastening element (49) as a sealing device (42) by means of a fluid-sealed material locking connection (52), especially a welded connection (53) and / or an adhesive connection, for tightly isolating each lubrication chamber (44) from each compression chamber (29).

11. The reciprocating compressor according to claim 10, Its features are, The at least one material locking connection (52) between the at least one diaphragm (34) and the at least one fastening element (49) is constructed to completely surround one of the longitudinal axes (41) of the cylinder (6) in the tangential direction (58).

12. The piston compressor according to one or more of the preceding claims, Its features are, The at least one diaphragm (34) is configured as at least one bellows (34).

13. The reciprocating compressor according to one or more of the preceding claims, Its features are, The mechanical device (40) includes a shaft (2) having at least one cam (3), and the at least one piston (5) is indirectly supported on the shaft (2) having the at least one cam (3) by means of a roller shoe (9) and a working roller (10).

14. The reciprocating compressor according to one or more of the preceding claims, Its features are, The stroke height of each piston (5) between the top dead center and the bottom dead center is less than 30%, 10%, 5% or 3% of the extension dimension (48) of the at least one diaphragm (34) in the direction of the longitudinal axis (41) of the cylinder (6) related to the stroke movement.

15. The reciprocating compressor according to one or more of the preceding claims, Its features are, The clearance volume of each compression chamber (29) is less than 10%, 5%, 3% or 2% of the stroke volume of each compression chamber (29).

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