Vacuum machine

Abstract

To provide a vacuum device which comprises, e.g., a cartridge vacuum pump and a vacuum chamber, and in which a simple and efficient seal between sections having respective different pressure levels is achieved.SOLUTION: A vacuum device (100) comprises an inner wall 118 and an outer wall 122. The outer wall surrounds the inner wall such that a gap 130 is formed between the inner wall and the outer wall. The gap includes at least one sealing region 134, in which the gap has a predetermined distance between the inner wall and the outer wall. The at least one sealing region is arranged between two areas 132, 138 of the gap. In the two areas, the respective distances between the inner wall and the outer wall are greater than the predetermined distance between the inner wall and the outer wall in the sealing region.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a vacuum appliance comprising an inner wall and an outer wall, the outer wall surrounding the inner wall such that a gap is formed between the inner wall and the outer wall, the gap forming at least one sealing area. [Background technology]

[0002] Vacuum pumps are usually stand-alone units that have their own housing and can be connected to a vacuum chamber or another vacuum pump, for example via a flange connection at the inlet opening of the housing. In addition, so-called cartridge vacuum pumps exist, which can be fitted into the outer wall of a vacuum chamber so that this outer wall forms part of the housing of the so-called vacuum pump.

[0003] Such cartridge constructions are used, for example, in so-called split-flow turbomolecular pumps, which, in addition to the main intake, have additional intake openings or ports, allowing different pumps at different pressure levels to be realized. The additional ports are typically arranged laterally in such pumps, i.e., laterally with respect to the axis of rotation of the rotor of the turbomolecular pump.

[0004] However, various parts of such a vacuum pump, which are at different pressure levels during operation of the vacuum pump, must be sealed from one another to avoid or at least reduce backflow within the vacuum pump. To seal the parts of the vacuum pump, each with its respective intake opening or port, from one another, orbiting elastomeric seals are typically used. The elastomeric seals are configured, for example, as O-rings and are pressurized axially, i.e., parallel to the axis of rotation of the rotor of the vacuum pump.

[0005] Due to the circumferential elastomer seal, a relatively large gap width between the cartridge vacuum pump and the vacuum chamber can be selected in such a cartridge vacuum pump, so that a sufficient gap exists between the cartridge vacuum pump and the vacuum chamber, allowing for a reliable and relatively easy assembly of such a cartridge vacuum pump.

[0006] A disadvantage of using such axially pressurized elastomer seals is that a stepped "fir tree" shape of the cartridge housing of the vacuum pump is required, in which the diameter of each part of the vacuum pump increases axially starting from the low pressure side, so that various parts or sealing planes of the vacuum chamber engage with respective opposing surfaces of the vacuum chamber for sealing. Therefore, such a "fir tree" shape of the cartridge housing of the vacuum pump requires a relatively large construction space.

[0007] Radially pressurized seals between various portions of a cartridge vacuum pump at various pressure levels may be positioned at approximately the same diameter relative to the axis of rotation of the rotor. However, such radially pressurized seals require tangential displacement to engage the seals, which would result in relatively strong frictional forces being generated during insertion of such a cartridge vacuum pump into a vacuum chamber. Moreover, these frictional forces are often too great in practice, further risking pinching of various portions of the vacuum pump and vacuum chamber.

[0008] However, since cartridge vacuum pumps with radially pressurized seals allow for a compact design of the vacuum pump with reduced construction space, special coating of the elastomeric seals, for example with PTFE (Teflon®), has been considered, as described, for example, in WO 2018 / 229473. However, special coating of the elastomeric seals requires additional effort. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] International Publication No. 2018 / 229473 Summary of the Invention [Problem to be solved by the invention]

[0010] SUMMARY OF THE INVENTION It is an object of the present invention to provide a vacuum device, for example comprising a cartridge vacuum pump and a vacuum chamber, which achieves a simple and efficient seal between parts at different pressure levels. [Means for solving the problem]

[0011] This problem is solved by a vacuum device having the features of claim 1. Advantageous developments of the invention are described in the dependent claims, the description and the drawings.

[0012] The vacuum device includes an inner wall and an outer wall surrounding the inner wall such that a gap is formed between the inner wall and the outer wall. The gap has at least one sealing region, where the gap has a predetermined distance between the inner wall and the outer wall in the sealing region. The sealing region is disposed between two regions of the gap, where each distance between the inner wall and the outer wall in the two regions is greater than the predetermined distance between the inner wall and the outer wall in the sealing region.

[0013] A sealing area is disposed between two regions of the gap, and during operation of the vacuum equipment, a pressure exists in at least one of the two regions of the gap that is higher than the pressure in the other one of the two regions. The sealing area therefore represents a gap seal, which is formed solely by the inner and outer walls of the vacuum equipment and does not require an elastomeric seal, for example in the form of an O-ring, or other sealing material. The vacuum equipment therefore has at least one such gap seal. However, this does not exclude the vacuum equipment from having other seals in addition to the gap seal.

[0014] The predetermined spacing may have a value of up to one to two tenths of a millimeter, with values ​​of less than 50 micrometers being preferred. Additionally, the predetermined spacing may be approximately zero, so that the inner and outer walls at least partially meet around their perimeters.

[0015] Within the sealing area, the gap between the inner wall and the opposing outer wall has a width that is smaller than the width of the gap in two areas outside the sealing area. Because the gap seal or sealing area of ​​the gap is formed by narrowing the gap or reducing the distance between the inner wall and the outer wall, the extension of the gap may continue continuously through the sealing area, without, for example, needing to increase the circumference of the inner and / or outer wall across the sealing area. If the inner wall is formed, for example, by a cartridge vacuum pump with a rotor having an axially extending rotation axis, the sealing area may extend approximately parallel to the axial direction.

[0016] Therefore, in the vacuum appliance according to the present invention, the circumference of the inner wall does not need to be increased to form the sealing area, and therefore no additional structural space is required for sealing between the areas between which the sealing area is located. In particular, the structural space required for the vacuum appliance is reduced compared to the vacuum appliances described at the beginning, which have a stepped "fir-tree" cartridge housing of the vacuum pump that forms the inner wall of the vacuum appliance. Furthermore, additional elements, such as specially coated elastomer seals, are not required for the sealing area, since the sealing area is formed exclusively by the inner and outer walls as a gap seal.

[0017] According to one embodiment, the vacuum equipment may include a vacuum pump having an inner wall and a vacuum chamber having an outer wall. The outer wall of the vacuum chamber may be configured to accommodate the inner wall of the vacuum pump. In other words, in this embodiment, the vacuum equipment may include a cartridge vacuum pump that is fitted or inserted into the vacuum chamber. A sealing area may be provided between at least two pump stages of the vacuum pump. Thus, the sealing area here forms a gap seal, which is formed exclusively by the inner wall of the vacuum pump and the outer wall of the vacuum chamber, without the need for a separate sealing element. This enables efficient sealing between the pump stages of the vacuum pump. The seal requires only a small amount of structural space relative to the vacuum pump.

[0018] The vacuum pump may further have a plurality of pump stages, for example three or more pump stages, and a respective sealing region may be provided between each two pump stages of the vacuum pump. Furthermore, an intermediate suction section may be provided in the axial region between each two pump stages of the vacuum pump.

[0019] The intermediate suction section may be arranged, for example, in the axial direction of the vacuum pump, near at least one sealing area or between two sealing areas separating two pump stages of the vacuum pump, each at a different pressure level. Alternatively, the intermediate suction section may be arranged between a gap seal having a sealing area formed by the inner and outer walls of the vacuum equipment and an elastomeric seal defining a pump stage of the vacuum pump at a higher pressure level than at least one other pump stage. Such an elastomeric seal, unlike the gap seal, may be axially pressurized between the inner and outer walls of the vacuum equipment.

[0020] According to another embodiment, multiple sealing areas may be arranged along the gap. The sealing areas, like the gap between the inner and outer walls, extend substantially axially, e.g., substantially parallel to the rotation axis of the rotor of the vacuum pump. Furthermore, the multiple sealing areas may be centered with respect to the rotation axis of the rotor of the vacuum pump. The multiple sealing areas allow, for example, a stepped transition between various pump stages of the vacuum pump, each at a different pressure level, i.e., from a high vacuum zone to a medium vacuum zone at a very high pressure level.

[0021] A sealing area is arranged between two regions of the gap, and the sealing area may extend at a predetermined angle to at least one of the two regions of the gap, in which case the sealing area may extend, in particular outside the sealing area, perpendicular to at least one of the two regions or in the same direction as these two regions. The predetermined angle may therefore be 90° or 0° in this special case. Furthermore, an oblique or conical extension of the gap within the sealing area is possible, i.e., it may extend at an angle of approximately 45° to at least one of the regions outside the sealing area.

[0022] For example, when a cartridge vacuum pump is inserted into a vacuum chamber and the inner and outer walls of the vacuum equipment, e.g. the inner wall of the vacuum pump and the outer wall of the vacuum chamber, come into contact with each other, it may be advantageous to have a conical arrangement of the sealing area, i.e. the sealing area extends perpendicularly in a stepped manner at about 45° to the axial direction, so that only small or negligible shear forces occur and therefore the frictional forces between the inner and outer walls are reduced.

[0023] Furthermore, an additional seal may be disposed between the gap and an external region of the vacuum equipment where atmospheric pressure exists. Such an additional seal may thus be located outside the sealing region forming the gap seal, e.g., in the axial direction of the vacuum pump, and seal the gap seal against atmospheric pressure. This additional seal may be, for example, an elastomeric seal in the form of an O-ring. However, in such an embodiment, the vacuum equipment only requires a single additional seal to insulate the gap seal or sealing region at a lower pressure level.

[0024] According to another embodiment, at least one sealing area between the inner and outer walls of the vacuum device may include a metal contact between the inner and outer walls. Such a metal contact may be referred to as a "support point" for a cartridge vacuum pump, for example, in a vacuum chamber. A metal contact may be advantageous when the vacuum device is designed for ultra-high vacuum applications, for example, because metal seals have significantly better outgassing properties than, for example, elastomeric seals. Furthermore, a metal contact may improve heat transfer, which may be advantageous, for example, when heating the vacuum device.

[0025] Alternatively, the inner and outer walls may not have metal contact. In such an embodiment, one or more sealing areas may be configured with respect to the spacing between the inner and outer walls so that each sealing area or each gap seal is adapted to the desired pressure difference through each sealing area. Additionally, an elastomeric seal may be provided to seal against ambient pressure, i.e., as a so-called final seal before transition to the space outside the vacuum equipment. When the inner and outer walls of the vacuum equipment do not have metal contact, vibration isolation can be achieved, for example, between the vacuum chamber of the vacuum equipment and the vacuum pump.

[0026] According to another embodiment, the ratio of the length of the sealing area along the gap to the predetermined distance between the inner and outer walls in the sealing area is greater than 5, preferably greater than 10. The predetermined distance may also be referred to as the height of the seal gap in the direction perpendicular to the inner and outer walls. The greater the ratio of the length of the sealing area along the gap or gap in the sealing area to the predetermined distance or gap height in the sealing area, the lower the vacuum-technical conductance of the sealing area and, conversely, the greater the sealing action.

[0027] The gap height in the sealing area or the predetermined distance between the inner and outer walls in the sealing area may be 0.2 mm or less, preferably 0.05 mm or less. The required setting of the predetermined distance or gap height in the sealing area depends on the required seal, i.e., the pressure differential required across each sealing area, as well as on the backflow, type of gas, pumping speed inside the pump and the resulting gas load.

[0028] However, it has been found that practical applications require narrow gap dimensions of 0.2 mm or less within the sealing area. A very small, predetermined spacing between the inner and outer walls within the sealing area, for example less than 0.05 mm, can be achieved by reducing the tolerances of the components and improving the surface quality of the inner and outer walls. However, the smaller the predetermined spacing selected, the higher the manufacturing costs of the corresponding components of the vacuum equipment that form the inner and outer walls.

[0029] The predetermined gap between the inner wall and the outer wall may occupy a value within the sealing region of, for example, 0.05 mm to less than 0.1 mm, 0.1 mm to less than 0.15 mm, or 0.15 mm to less than 0.2 mm. Because the outer wall surrounds the inner wall and the inner wall may orbit, for example, annularly, around the longitudinal axis of the vacuum pump, the actual gap between the inner wall and the outer wall may vary around the circumference of the outer wall, i.e., may not be a constant size. Thus, the predetermined gap between the inner wall and the outer wall may be an average value of the gap dimension along the circumference of the outer wall relative to the inner wall. Thus, the aforementioned ranges of the predetermined gap or gap width within the sealing region relate to the average value of this gap dimension along the circumference of the inner wall and the outer wall, respectively.

[0030] Furthermore, the length of the sealing area along the gap may be greater than 5 mm, preferably greater than 40 mm. Alternatively, the length of the sealing area along the gap may be less than 5 mm, provided that in this case the predetermined distance between the inner and outer walls in the sealing area must be very small, e.g., less than 0.05 mm, to provide the lowest possible vacuum-technical conductance for sufficient sealing across the sealing area. Furthermore, the length of the sealing area along the gap may be greater than 5 mm and less than 10 mm, greater than 10 mm and less than 15 mm, or greater than 15 mm and less than 40 mm, or may be greater than 40 mm. However, in this case, the predetermined distance between the inner and outer walls in the sealing area must be selected so that the required pressure difference across the sealing area can be achieved.

[0031] Yet another object of the present invention is a vacuum pump adapted to be fitted into a vacuum chamber and having a wall extending annularly about a longitudinal axis of the vacuum pump, the wall of the vacuum pump having at least one portion at a predetermined distance from the longitudinal axis, which portion forms at least one sealing area with an opposing wall of the vacuum chamber, within the sealing area a gap between the wall of the vacuum pump and the opposing wall of the vacuum chamber having a width that is smaller than the width of the gap outside the sealing area.

[0032] In other words, the vacuum pump is intended to form at least one gap seal with the wall of the vacuum chamber when inserted into the vacuum chamber, and thus the seal area is located between two areas of the gap between the vacuum pump and the vacuum chamber, in which the respective spacing between the wall of the vacuum pump and the wall of the vacuum chamber is greater than the predetermined spacing between these walls in the seal area.

[0033] The invention will now be described on the basis of exemplary advantageous embodiments with reference to the accompanying drawings. [Brief explanation of the drawings]

[0034] [Figure 1] 1 illustrates an exemplary cartridge vacuum pump according to the prior art. [Figure 2] 1 shows a vacuum apparatus according to the present invention comprising a vacuum pump and a vacuum chamber, with at least one gap seal provided between the vacuum pump and the vacuum chamber. [Figure 3] 1 illustrates an embodiment having a conically extending gap seal between a vacuum pump and a vacuum chamber of a vacuum instrument. [Figure 4] 10 illustrates another embodiment having a radially extending gap seal between a vacuum pump and a vacuum chamber of a vacuum instrument. [Figure 5] 1 illustrates another embodiment of a vacuum apparatus, where at least one of the gap seals forms a metal-to-metal contact between the vacuum pump and the vacuum chamber. [Figure 6] 10 shows another embodiment of a vacuum device having an intermediate suction section. DETAILED DESCRIPTION OF THE INVENTION

[0035] FIG. 1 shows an exemplary split-flow turbomolecular pump 10. The split-flow turbomolecular pump 10 has a circular, so-called cartridge housing 20 and three inlet openings or ports 30, 32, and 34. The cartridge housing 20 allows the turbomolecular pump 10 to be fitted or inserted into a vacuum chamber. Such fitting of the vacuum pump into a vacuum chamber is shown schematically in cross section in FIG. 2A.

[0036] The three intake openings 30, 32, 34 of the turbomolecular pump include intake opening 30 or port H0, which constitutes the main intake opening of turbomolecular pump 10 and is at the lowest pressure level P0 reached by turbomolecular pump 10 during operation. Port H0 is located at the axial end of turbomolecular pump 10 and is simultaneously centered with respect to the longitudinal axis of turbomolecular pump 10, which represents the axis of rotation for the rotor of turbomolecular pump 10.

[0037] The two other intake openings 32, 34 of the turbomolecular pump 10 include two other ports H1 and H2 located laterally in the cartridge housing 20 of the turbomolecular pump 10. Port H1 is at a pressure level P1 higher than the pressure level P0 at port H0 when the turbomolecular pump 10 is operating, while port H2 is at a pressure level P2 higher than the pressure level P1 at port H1 and therefore greater than the pressure level P0 at port H0 when the turbomolecular pump 10 is operating.

[0038] Due to the different pressure levels P0, P1, and P2 at ports H0, H1, and H2 of the turbomolecular pump 10, sealing between the different regions or ports of the turbomolecular pump 10 is necessary during operation of the turbomolecular pump 10. Sealing between the various pressure levels P0, P1, and P2 or ports H0, H1, and H2, as well as between port H2 and the ambient pressure outside the turbomolecular pump 10, is provided by respective elastic seals 40, 42, and 44. The seals 40, 42, and 44 are each formed as a surrounding O-ring.

[0039] In the exemplary prior art turbomolecular pump 10, the elastic seals 40, 42, and 44 are pressurized axially, i.e., parallel to the longitudinal axis of the turbomolecular pump 10. This gives the turbomolecular pump 10 a stepped "fir tree" shape, in which the diameter of each section of the turbomolecular pump 10 gradually increases from port H0 toward the opposite axial end of the turbomolecular pump 10. Similarly, the diameter of each of the O-rings forming each elastic seal 40, 42, and 44 also increases axially from port H0. Due to the stepped "fir tree" shape with increasing diameters, the prior art turbomolecular pump 10 requires a relatively large structural space when it is to be installed in a vacuum chamber.

[0040] 2 shows a vacuum apparatus 100 according to the invention, which includes a vacuum pump 110 configured as a turbomolecular pump and a vacuum chamber 120. Similar to the turbomolecular pump 10 shown in FIG. 1, the vacuum pump 110 has a cartridge housing, which allows the vacuum pump 110 to be fitted or inserted into the vacuum chamber 120. Furthermore, the vacuum pump 110 also has a first inlet opening 112 and two laterally arranged inlet openings 114, 116, where the first inlet opening 112 is designated port H0 and is located axially above the vacuum pump 110, and the inlet openings 114, 116 are designated port H1 and port H2, respectively. The two laterally arranged inlet openings 114, 116 allow for variable pumping by the vacuum pump 110, so that the vacuum pump 110 is configured here as a split-flow turbomolecular pump.

[0041] The vacuum pump 110 further has a longitudinal axis 117, which is also the axis of rotation for a rotor (not shown) of the vacuum pump 110. When the vacuum pump 110 is inserted into the vacuum chamber 120, the vacuum pump 110 is further centered about the longitudinal axis 117.

[0042] The vacuum apparatus 100 has an inner wall 118 formed by the cartridge housing of the vacuum pump 110 and an outer wall 122 of the vacuum chamber 120. A gap 130 is formed between the inner wall 118 and the outer wall 120, and the gap 130 is shown enlarged in Figures 2B and 2C. The gap 130 has two sealing regions 134, 140 along its extension from the inlet opening 112 or port H0 to the inlet opening 116 or port H2, where the gap 130 has a reduced width or predetermined reduced spacing between the inner wall 118 and the outer wall 122.

[0043] 2B shows an enlarged view of portion "B" of FIG. 2A, including first sealing area 134 between ports H0 and H1. First sealing area 134 is disposed between two regions 132, 138 of gap 130, where the respective spacings between inner wall 118 and outer wall 122 in the two regions 132, 138 are greater than the predetermined spacing or gap width between inner wall 118 and outer wall 122 in sealing area 134.

[0044] In other words, the sealing region 134 has a reduced width along its length 136 along the gap 130, i.e., the sealing region 134 is disposed between regions 132, 138, where the width between the inner wall 118 and the outer wall 122 is smaller than the width of the gap 130 at regions 132, 138. The same is true for the second sealing region 140 shown in FIG. 2A. The sealing region 140 is disposed between ports H1 and H2 and between region 138 of the gap 130 and another region 142, where the gap 130 has a larger width than at the sealing region 140.

[0045] At its axial end opposite the axial end of port H0, vacuum pump 110 has an elastomeric seal 150 configured as a surrounding O-ring, which seals gap 130 and thus the entire vacuum pump 110 against ambient pressure.

[0046] 2C, because the inner wall 118 and outer wall 122 of the vacuum equipment 100 may deviate from an ideal coaxial shape, the gap 130 has a varying width at each position along the circumference of the vacuum pump 110, as illustrated by width 162 at position 160. Thus, a given spacing between the inner wall 118 and outer wall 122 in the sealing regions 134, 140 applies to the average gap size or width of the gap 130 around the circumference of the vacuum pump 110.

[0047] In the example shown in Figure 2A, the sealing areas 134, 140 have a predetermined spacing of approximately 0.061 mm between the inner wall 118 and the outer wall 122, where diameter tolerances are taken into account and a range of 0.025 mm to 0.097 mm is set for the width of the gap 130 within the sealing areas 134, 140. It has been found that the width of the gap 130 within the sealing areas 134, 140 should be less than 0.2 mm. The length 136 of the sealing area 134 along the gap 130 ranges from 5 mm to approximately 40 mm, where a length 136 of approximately 15 mm was specifically used in the example of Figure 2A.

[0048] The sealing area 134 seals the pressure level P0 at port H0 or the intake opening 112 against a pressure level P1 at port H1 or the intake opening 114. The pressure level P1 is greater than the pressure level P0 at port H0. Similarly, the second sealing area 140 seals the pressure level P1 at port H1 against a pressure level P2 at port H2 or the intake opening 116. The pressure level P2 is now greater than the pressure level P1. The sealing effect of the sealing areas 134, 140 is provided by the vacuum-technical conductance along the respective sealing areas 134, 140. The lower the vacuum-technical conductance, the better the sealing effect of the respective sealing area or gap seal 134, 140. The vacuum-technical conductance, here, is lower the greater the ratio of the length 136 of the sealing area 134 along the gap 130 to the width of the gap 130 within the sealing area 134, 140. In this example, the ratio is greater than five.

[0049] Both sealing areas 134, 140 provide sealing between the various pressure levels P0, P1, and P2 within the vacuum pump 110 as a whole, without the need for an axially pressurized elastomeric seal. Based on the two axially extending sealing areas or gap seals 134, 140 in the example of FIG. 2A , the increase in the radial diameter of the vacuum pump 110 between ports H0 and H2 is very small, i.e., much smaller than that of the turbomolecular pump 10 of the background art shown in FIG. 1 . This allows the vacuum pump 110, when inserted into the vacuum chamber 120, to require less structural space than the turbomolecular pump 10 of FIG. 1 . However, to seal the vacuum pump 110 against ambient pressure, an elastomeric seal 150, which is a single elastomeric seal in the example of FIG. 2A , is required because the pressure difference between the pressure level P2 in the area of ​​port H2 and ambient pressure would be too large for the gap seal.

[0050] 3 shows a portion of one embodiment of the vacuum equipment 100. In this embodiment, unlike the embodiment shown in FIGS. 2A and 2B, the sealing area 134 extends obliquely or conically rather than axially. Specifically, the sealing area 134 of the gap 130 between the vacuum pump 110 and the vacuum chamber 120 extends at a predetermined angle relative to the axial direction established by the longitudinal axis 117 of the vacuum pump 110 (see FIG. 2A). The sealing area 134 is disposed between other regions 132, 138 of the gap 130, and similarly extends obliquely at a predetermined angle relative to the other regions 132, 138 of the gap 130, so that the sealing area 134 forms a conical annular surface.

[0051] An advantage of the oblique or conical extension of the sealing area 134 is that it reduces frictional forces when the vacuum pump 110 is inserted into the vacuum chamber 112 compared to the axial extension shown in Figure 2A. However, the oblique or conical extension of the sealing area 134 does result in a radial expansion of the vacuum pump 110 across the sealing area or gap seal 134, i.e., to a similar, albeit slightly smaller extent, than would be the case with the "fir tree" arrangement of pumping stages of a cartridge vacuum pump (see Figure 1).

[0052] Figure 4 shows another embodiment of the vacuum apparatus 100 that is equivalent to the embodiment of Figure 3. However, in the embodiment of Figure 4, the sealing area 134 extends almost completely radially, thus forming a step in the vacuum pump 110 within the inner wall 118 of the vacuum apparatus 100. The embodiment of Figure 4 has the advantage that, due to the generally radial extension of the sealing area 134, axial frictional forces that arise when the vacuum pump 110 is inserted into the vacuum chamber 120 are almost completely suppressed. However, the stepped extension of the gap 130 through the sealing area 134 results in an even greater expansion of the diameter of the vacuum pump 110 through the sealing area 134 from a region 132 having pressure level P0 at port H0 to a region 138 of the gap 130 that is at pressure level P1 at port H1.

[0053] 5 shows another embodiment of the vacuum device 100. In this embodiment, similar to the embodiment shown in FIG. 2, respective sealing areas 134, 140 are provided between the pressure level P0 of the port H0 and the pressure level P1 of the port H1, or between the pressure level P1 and the pressure level P2 of the port H2. However, the sealing area 134 differs from the sealing area shown in FIG. 2 in that the gap 130 of this sealing area extends obliquely or conically, i.e., at an angle greater than 0° and less than 90° relative to the longitudinal axis 117 of the vacuum pump 110, as also shown in FIG. 3. Furthermore, in the sealing area 134, in the embodiment shown in FIG. 5, a metal-to-metal contact occurs between the vacuum pump 110 and the vacuum chamber 120.

[0054] 5, the gap 130 between the vacuum pump 110 and the vacuum chamber 120 at the sealing area 134 is pressed into contact, so that the inner wall 118 of the vacuum pump 110 and the outer wall 122 of the vacuum chamber 120 are in direct contact or abutment. The contact point formed by the sealing area 134 between the vacuum pump 110 and the vacuum chamber 120 is used as a so-called support point when the vacuum pump 110 is inserted into the vacuum chamber 120. The position of the contact point formed by the sealing area 134 is selected to improve the vibration characteristics of the vacuum pump 110 during operation.

[0055] If the vacuum device 110 is designed for the ultra-high vacuum range, a metal contact between the vacuum pump 110 and the vacuum chamber 120 in the sealing area 134 is even more advantageous. Due to the metal contact in the sealing area 134, the outgassing characteristics of the vacuum device 100 are improved compared to the use of an elastomeric seal, because, with the exception of the elastomeric seal 150 for sealing against atmospheric pressure, Non This is because no metal material is required.

[0056] Additionally, the metal contact 134 improves heat transfer between the vacuum chamber 120 and the vacuum pump 110, which is advantageous for warming the vacuum equipment 100 for operation in the ultra-high vacuum range.

[0057] 5 also includes an elastomeric seal 150 at the axial end of the vacuum pump 110 axially opposite port H0 to seal port H2 and a region 142 of gap 130 near port H2 against ambient pressure. A further gap 152 is provided between the elastomeric seal 150 and an exterior region of the vacuum apparatus 100.

[0058] FIG. 6 shows another embodiment of the vacuum device 100. In this embodiment, an intermediate suction section via an additional port 180 is provided between a region 132 of the gap 130 having a pressure level P0 of port H0 and a region 138 of the gap 130 having a pressure level P1 of port H1. Specifically speaking, in order to seal the region 132 at the pressure level P0 against another region 138 at the pressure level P1 where the gap 130 has a larger gap width compared to the seal region 134, on the one hand, a seal region 134 with a narrowed or reduced width of the gap 130 is provided. Additionally, an elastomeric seal 170 for sealing between the pressure levels P0 and P1 is provided. An additional port 180 for intermediate suction of the gas load Q specifically indicated by an arrow is located in the region between the seal region 134 with a reduced width of the gap 130 and the elastomeric seal 170.

[0059] Based on the intermediate suction via the additional port 180, the gap 130 has a pressure PX that is lower than the pressure level P1 but higher than the pressure level P0 between the seal region 134 and the region 138 at the pressure level P1, or above or upstream of the elastomeric seal 170 in the axial direction. In other words, P0 < PX < P1 applies.

[0060] In the embodiment of the vacuum apparatus 100 shown in FIG. 6 , the seal region 134 may include a contact point or metal contact between the vacuum pump 110 and the vacuum chamber 120. However, alternatively, metal contact between the vacuum pump 110 and the vacuum chamber 120 may be prevented at the seal region 134. Thus, in the embodiment shown in FIG. 6 , the vacuum apparatus 100 may be configured entirely without metal contact at the seal regions 134, 140 or gap seals formed therein. Without such metal contact, the vacuum pump 110 has improved thermal insulation from the vacuum chamber 120. Such improved thermal insulation may be advantageous, such that heat flow from an application within the vacuum chamber 120 is not transferred to the vacuum pump 110, or vice versa, such that a warmed vacuum pump 110 does not generate unnecessary heat flow to the vacuum chamber 120 and the application located therein.

[0061] Metallic contact between the vacuum pump 110 and the vacuum chamber 120 can also be prevented in the area of ​​the elastomeric seal 150 and in the gap 152 adjacent to the elastomeric seal 150, for example by configuring the threaded connection between the vacuum pump 110 and the vacuum chamber 120 in the area of ​​the gap 152 as a threaded connection that has no metallic contact with the vacuum pump 110 (see FIG. 5). In the case of such a threaded connection, the shank of each screw is metallically connected to the vacuum chamber 120, while the head of each screw is insulated from the vacuum chamber 110 by a plastic part. This allows the vacuum chamber 120 and the vacuum pump 110 to be electrically and thermally insulated from each other and also provides vibration isolation between them. The present application relates to the invention described in the claims, but also includes the following as other aspects. 1. In a vacuum device (100), an inner wall (118); an outer wall (122) surrounding the inner wall (118) such that a gap (130) is formed between the inner wall (118) and the outer wall (122); The gap (130) has at least one sealing area (134), and in the sealing area (134), the gap (130) has a predetermined distance between the inner wall (118) and the outer wall (122); A vacuum device (100) in which at least one of the sealing areas (134) is disposed between two areas (132, 138) of the gap (130), and in the two areas (132, 138), the respective spacings between the inner wall (118) and the outer wall (122) are greater than a predetermined spacing between the inner wall (118) and the outer wall (122) in the sealing area (134). 2. a vacuum pump (110) having said inner wall (118); a vacuum chamber (120) having an outer wall (122) configured to accommodate the inner wall (118) of the vacuum pump (110); The vacuum device (100) according to claim 1 further comprising: 3. The vacuum pump (110) has multiple pumping stages; The vacuum pump (110) has a respective sealing area (134, 140) between each two pump stages. The vacuum equipment (100) described above in 2. 4. The vacuum device (100) according to claim 3, wherein an intermediate suction section (180) is provided in an axial region between two pump stages of the vacuum pump (110). 5. 5. The vacuum device (100) according to any one of 1 to 4 above, wherein a plurality of sealing regions (134, 140) are arranged along the gap (130). 6. 6. The vacuum device (100) of any one of 1 to 5 above, wherein the sealing area (134) is disposed between two areas (132, 138) of the gap (130), and the sealing area (134) extends at a predetermined angle relative to at least one of the two areas (132, 138). 7. The vacuum device (100) of claim 6, wherein the sealing area (134) is disposed between two areas (132, 138) of the gap (130), and the sealing area (134) extends perpendicular to at least one of the two areas (132, 138). 8. The vacuum device (100) of claim 6, wherein the sealing area (134) is disposed between the two areas (132, 138) of the gap (130), and the sealing area (134) extends in the same direction as the two areas (132, 138). 9. 9. The vacuum device (100) of any one of 1 to 8 above, wherein an additional seal (150) is disposed between the gap (130) and an external region of the vacuum device (100) where atmospheric pressure is present. 10. At least one sealing area (134, 140) between the inner wall (118) and the outer wall ( 122 10. The vacuum device (100) of any one of 1 to 9 above, wherein there is a metal contact between the vacuum device (100) and the metal contact between the vacuum device (100). 11. 10. The vacuum device (100) of any one of claims 1 to 9, wherein there is no metal contact between the inner wall (118) and the outer wall (122). 12. 12. The vacuum device (100) of any one of 1 to 11 above, wherein the ratio of the length (136) of the sealing area (134) along the gap (130) to the predetermined spacing between the inner wall (118) and the outer wall (122) within the sealing area (134) is greater than 5, and preferably greater than 10. 13. 13. The vacuum device (100) of any one of 1 to 12, wherein the predetermined gap between the inner wall (118) and the outer wall (122) in the sealing area (134) is 0.2 mm or less, preferably 0.05 mm or less. 14. The length (136) of the sealing area (134) along the gap (130) is 5 m m Rimo big 14. The vacuum device (100) of any one of 1 to 13 above, preferably greater than 40 mm. 15. In the vacuum pump (110), The vacuum pump (110) is configured to be fitted into a vacuum chamber (120) and has a wall (118) extending annularly about a longitudinal axis (117) of the vacuum pump (110); the wall (118) has at least one portion at a predetermined distance from the longitudinal axis (117), the portion forming at least one sealing area (134) with an opposing wall (122) of the vacuum chamber (120), and in the sealing area (134), a gap (130) between the wall (118) of the vacuum pump (110) and the opposing wall (122) of the vacuum chamber (120) has a width that is smaller than the width of the gap (130) outside the sealing area (134); Vacuum pump (110). [Explanation of symbols]

[0062] 10 Split-flow turbomolecular pump 20 Cartridge housing 30, 32, 34 Intake opening, port H0, H1 or H2 40, 42, 44 Axially pressurized elastomer seals, O-rings 100 Vacuum equipment 110 Vacuum Pump 112, 114, 116 Intake opening, port H0, H1 or H2 117 Axial longitudinal axis of vacuum pump 118 Inner Wall 120 Vacuum Chamber 122 Outer Wall 130 Gap 132 Area of ​​the gap at pressure level P 134 Seal Area 136 Length of sealing area along the gap 137 Area of ​​the gap at pressure level PX 138 Area of ​​the gap at pressure level P1 140 sealing area 142 Area of ​​the gap at pressure level P2 150 Elastomer seal 152 Gap between elastomer seal and exterior area 160 Positions around the outer wall 162 Gap width 170 Elastomer seal 180 additional ports

Claims

1. In a vacuum device (100), A vacuum pump (110) and a vacuum chamber (120) are provided. The vacuum pump (110) has a plurality of pumping stages and is fitted within the vacuum chamber (120), and has an inner wall (118) extending annularly about a longitudinal axis (117) of the vacuum pump (110); The vacuum chamber (120) has an outer wall (122) that accommodates the inner wall (118) of the vacuum pump (110); A gap (130) is formed between the inner wall (118) and the outer wall (122), and the gap (130) is provided with sealing areas (134, 140) acting as gap seals between each of two pump stages of the vacuum pump (110), and the width of the gap (130) in the sealing areas (134, 140) is smaller than the width of the gap (130) other than the sealing areas (134, 140), thereby forming a gap seal.

2. 2. The vacuum equipment (100) of claim 1, wherein the vacuum pump (110) is provided with an intermediate suction section (180) in an axial region between two pump stages.

3. The vacuum apparatus (100) of claim 1 or 2, wherein a plurality of sealing areas (134, 140) are disposed along the gap (130).

4. 3. The vacuum equipment (100) of claim 1 or 2, wherein the sealing area (134) is disposed between two areas (132, 138) of the gap (130), and the sealing area (134) extends at a predetermined angle with respect to at least one of the two areas (132, 138).

5. 5. The vacuum equipment (100) of claim 4, wherein the sealing area (134) is disposed between two areas (132, 138) of the gap (130), and the sealing area (134) extends perpendicular to at least one of the two areas (132, 138).

6. 5. The vacuum equipment (100) of claim 4, wherein the sealing area (134) is disposed between two areas (132, 138) of the gap (130), and the sealing area (134) extends in the same direction as the two areas (132, 138).

7. 3. The vacuum device (100) of claim 1 or 2, wherein an additional seal (150) is arranged between the gap (130) and an external area of ​​the vacuum device (100) where atmospheric pressure is present.

8. The vacuum apparatus (100) of claim 1 or 2, wherein there is a metal-to-metal contact between the inner wall (118) and the outer wall (122) in at least one sealing area (134, 140).

9. The vacuum apparatus (100) of claim 1 or 2, wherein there is no metal contact between the inner wall (118) and the outer wall (122).

10. 3. The vacuum equipment (100) of claim 1 or 2, wherein a ratio of a length (136) of the sealing area (134) along the gap (130) to a predetermined distance between the inner wall (118) and the outer wall (122) within the sealing area (134) is greater than 5, preferably greater than 10.

11. 3. The vacuum equipment (100) of claim 1 or 2, wherein the predetermined distance between the inner wall (118) and the outer wall (122) in the sealing area (134) is 0.2 mm or less, preferably 0.05 mm or less.

12. 3. The vacuum apparatus (100) of claim 1 or 2, wherein a length (136) of the sealing area (134) along the gap (130) is greater than 5 mm, preferably greater than 40 mm.

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