Vacuum pump with modularly configured Holbeck pump stages

Abstract

To improve flexibility of the structure related to characteristic values, such as the exhaust speed and / or compression performance and electric power consumption, in design of a pump.SOLUTION: A vacuum pump 111, in particular, a turbo molecular vacuum pump, includes at least one holweck pump stage having a holweck stator and a holweck rotor. The holweck stator has stator sleeves 10, 169. The stator sleeve has: a fixed end 14 attached to a housing portion 12 in a home position of the vacuum pump; and a free end 14 located at the opposite side of the fixed end in an axial direction. The holweck rotor has a rotor sleeve 163. The rotor sleeve encloses the stator sleeve while forming a holweck gap 173. In the vaccum pump, the stator sleeve is formed by multiple portions.SELECTED DRAWING: Figure 6

Description

[Technical Field]

[0001] The present invention relates to a vacuum pump, also referred to simply as a pump herein, in particular a turbomolecular vacuum pump, according to the preamble of claim 1, comprising an inner Holweck pump stage. [Background Art]

[0002] Vacuum pumps are used in various technical fields. Depending on requirements, a vacuum pump may have one or more pump stages. In general, Holweck pump stages belong to the category of molecular vacuum pumps, which form a molecular flow by rotating a Holweck rotor relative to a fixed Holweck stator. Basically, a vacuum pump may comprise one or more Holweck pump stages, wherein in this case the plurality of Holweck pump stages can be operated both in series and in parallel with each other. Typically, Holweck pump stages are used in turbomolecular vacuum pumps, wherein in this case the Holweck pump stages are connected downstream of one or more turbomolecular pump stages in the flow direction.

[0003] A Holbeck pump typically comprises a Holbeck rotor and a Holbeck stator. In this case, the Holbeck rotor has a rotor shaft, on which one or more Holbeck rotor sleeves are concentrically mounted, for example, by a disc-shaped Holbeck hub. In this case, the Holbeck hub and Holbeck rotor sleeves may be constructed as a single unit or one piece; alternatively, the Holbeck hub and Holbeck rotor sleeves may be initially manufactured as separate parts, which are later joined together, for example, by welding. Each Holbeck stator sleeve assigned to it has one or more Holbeck threads, forming a Holbeck gap together with each Holbeck rotor sleeve. The gas molecules to be pumped are pumped along the threads from the intake to the exhaust port of each Holbeck pump stage by the rotational motion of the Holbeck rotor relative to the Holbeck stator. The threaded portion has a Holbeck channel in the form of a helical, circumferential thread groove defined by the walls of the threaded portion, and as the rotor sleeve rotates relative to the status sleeve, gas molecules are compressed in the threaded portion.

[0004] Furthermore, a so-called "folded" Holbeck configuration is known, in which multiple Holbeck pump stages are concentrically arranged and engaged with each other internally and externally, so that the pumping directions of multiple radially continuous Holbeck pump stages are opposite to each other. Thus, two Holbeck pump stages continuous in the flow direction, namely a radially outer Holbeck pump stage and a radially inner Holbeck pump stage, have a common Holbeck status ree located radially between two rotor sleeves, each having Holbeck threads on both sides. The radially outer rotor sleeve may itself be surrounded by an outer status ree, thereby forming a further Holbeck pump stage together with the outer rotor sleeve. Unlike the status ree located radially outward of the outer rotor sleeve, in the context herein, a status ree located radially inward of the outer rotor sleeve is, naturally, also referred to as an inner status ree, even if it does not, in some cases, surround the inner rotor sleeve.

[0005] Basically, the Holbeck geometry and especially the configuration of the Holbeck threads affect the characteristic values ​​of each pump stage, such as the pumping speed and / or compression performance of the Holbeck pump stage and the power consumption of the pump motor. However, since the Holbeck geometry usually does not change over the axial extension length of the Holbeck status sleeve, the characteristic values ​​mentioned can only be adjusted within a limited range in the pump design. [Overview of the project] [Problems that the invention aims to solve]

[0006] Therefore, the fundamental problem of the present invention is to increase the degree of freedom in the configuration of the vacuum pump described at the beginning, with respect to characteristic values ​​such as pumping speed, compression performance, and power consumption when designing the pump. [Means for solving the problem]

[0007] This problem is solved by a vacuum pump having the features of claim 1, in particular by the fact that the status leaf, which is located inside or inside, is formed from multiple parts.

[0008] Therefore, the status sleeve may consist of multiple sleeve portions arranged axially in sequence or directly adjacent to one another, which can be handled separately within the scope of manufacture. In this case, the individual sleeve portions may differ, for example, with respect to the number of threads or the threaded portion formed by the threads, thereby effectively influencing the characteristic values ​​mentioned.

[0009] For example, an inner or internally located status leaf comprises a first sleeve portion having a first end and a second end located opposite to the first end, and at least one second sleeve portion having a first end and a second end located opposite to the first end, in which case the first end of the first sleeve portion is attached to the fixed housing portion of the vacuum pump and thus forms the fixed end of the status leaf. In contrast, the first end of the second sleeve portion is attached to the second end of the first sleeve portion. Therefore, if no other sleeve portion is attached to the second end of the second sleeve portion, the second end of the second sleeve portion forms the free end of the status leaf.

[0010] Therefore, because the stator sleeve is composed of multiple sleeve sections, for example, the first sleeve section may have a different thread geometry than the second sleeve section. Thus, different thread geometries may be used for each sleeve section, in which case a Holbeck stator can be configured as needed, thereby accurately modeling the pumping speed and / or compression performance of the Holbeck pump stage. For example, the first sleeve section and / or the second sleeve section can be replaced with another sleeve section having a different thread geometry, thereby changing the characteristics of the existing vacuum pump.

[0011] Insofar as different thread geometry shapes have been described above, this relates to the male threads and possibly female threads of a status leaf, formed by a plurality of thread grooves defined by the threaded portions formed on the status leaf and the groove bottoms formed by the status leaf. In this case, the male threads of the first sleeve portion may differ from the male threads of the second sleeve portion by at least one thread variable, in which case at least one thread variable is selected from a group of thread variables consisting of the number of threaded portions, the thread pitch, the width of the thread groove, the width of the threaded portion, and the height of the threaded portion on the groove bottom.

[0012] In one embodiment, to allow the individual sleeve portions to be interchanged with each other or replaced with other sleeve portions, it is conceivable that the first end of the first sleeve portion has a first end contour, and the first end of the second sleeve portion has a first end contour corresponding to the first end contour of the first sleeve portion. Similarly, the second end of the first sleeve portion may have a second end contour, and the second end of the second sleeve portion may have a second end contour corresponding to the second end contour of the first sleeve portion. In other words, the first end contours may each be molded to be essentially identical, and the second end contours may each be molded to be essentially identical. Therefore, when the first sleeve portion is attached to the housing portion in place by its first end, and thus the first end contour of the second sleeve portion corresponds to the first end contour of the first sleeve portion, the second sleeve portion may, if necessary, be attached to the housing portion in place by its first end contour.

[0013] To further enhance the interchangeability of individual sleeve portions, according to another embodiment, it may be further assumed that the first end of the first sleeve portion has a first end contour, and the first end of the second sleeve portion has a second end contour configured to complement the first end contour of the first sleeve portion. Similarly, the first end of the second sleeve portion may have a first end contour, and the second end of the first sleeve portion may have a second end contour configured to complement the first end contour of the second sleeve portion. Thus, each first end contour of one sleeve portion fits into each second end contour of the other sleeve portion, so that the two sleeve portions can be combined to form a single status sleeve.

[0014] Therefore, since the first end ring portion of the first sleeve portion is configured complementary to the second end contour portion of the second sleeve portion, the second sleeve portion may be attached to the housing portion in its fixed position by its first end contour portion in the manner described above, instead of the first sleeve portion, and the first sleeve portion may be attached to the second end contour portion of the second sleeve portion by its first end contour portion. Thus, even in the initial state of the vacuum pump, that is, with the first sleeve portion attached to the housing portion in its fixed position and the second sleeve portion attached to the second end of the first sleeve portion, the two sleeve portions can be swapped such that the second sleeve portion is attached to the housing portion in its fixed position by its first end contour portion and the first sleeve portion is attached to the second end contour portion of the second sleeve portion by its first end contour portion.

[0015] In another embodiment, each first end contour may have an annular first end face and an annular second end face that is axially recessed relative to the annular first end face. Similarly, each second end contour may have an annular first end face and an annular second end face that is axially recessed relative to the annular first end face. In this case, the annular first end face and the second end face are coaxially arranged with respect to each other and thus form stepped end contours.

[0016] If the annular first end face of the first end contour surrounds the annular second end face, then, based on the fact that the first end contour is complementarily configured with respect to the second end contour, the second end face surrounds the first end face in the second end contour. This also means that the distance between the first end face of the first end contour and the second end face of the second end contour is equivalent to the distance between the second end face of the first end contour and the first end face of the second end contour.

[0017] As mentioned above, the second end face of each end contour may be recessed axially relative to the first end face. However, in the first end contour, the first end face surrounds the second end face, and on the other hand, in the second end contour, the second end face surrounds the first end face. This means that the first end face of the first end contour is connected to the second end face of the first end contour via the inner surface of the cylinder, and the first end face of the second end contour is connected to the second end face of the second end contour via the outer surface of the cylinder.

[0018] Based on the complementary aspects of each end contour, the individual sleeve portions can be joined to each other in the manner described above to ensure a precise fit; however, according to a preferred embodiment, it may be assumed that the cylindrical outer surface of the second end contour has a slightly larger diameter than the cylindrical outer surface of the first end contour. Thus, the two sleeves may be joined to each other via press fitting along the cylindrical outer surface of the second end contour and the cylindrical inner surface of the first end contour.

[0019] Alternatively, it is likewise possible to provide a female thread along the mentioned inner cylindrical surface and a male thread matching the described female thread along the mentioned outer cylindrical surface, whereby the individual sleeve parts can be screwed together with each other.

[0020] Hereinafter, the present invention will be exemplarily described with reference to the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] [Figure 1] Fig. 1 shows a perspective view of a known turbomolecular pump. [Figure 2] Fig. 2 shows a bottom view of the turbomolecular pump of Fig. 1. [Figure 3] Fig. 3 shows a cross-sectional view of the turbomolecular pump taken along cutting line A-A shown in Fig. 2. [Figure 4] Fig. 4 shows a cross-sectional view of the turbomolecular pump taken along cutting line B-B shown in Fig. 2. [Figure 5] Fig. 5 shows a cross-sectional view of the turbomolecular pump taken along cutting line C-C shown in Fig. 2. [Figure 6] Fig. 6 is a schematic cross-sectional view for explaining the configuration of the inner Holweck stator sleeve according to the present invention. MODE FOR CARRYING OUT THE INVENTION

[0022] The turbomolecular pump 111 shown in Fig. 1 has a pump suction port 115 surrounded by a suction port flange 113. As is known per se, a recipient (not shown) may be connected to the pump suction port 115. Gas coming from the recipient is sucked from the recipient through the pump suction port 115, and can be pumped through the pump to a pump exhaust port 117. An auxiliary vacuum pump such as a rotary vane pump, for example, may be connected to the pump exhaust port 117.

[0023] In the orientation of the vacuum pump shown in FIG. 1, the intake flange 113 forms the upper end of the housing 119 of the vacuum pump 111. The housing 119 has a lower portion 121. An electronics housing 123 is laterally arranged on the lower portion 121. The electronics housing 123 accommodates electrical and / or electronic components of the vacuum pump 111, for example for actuating an electric motor 125 (see also FIG. 3) arranged in the vacuum pump. The electronics housing 123 is provided with a plurality of connections 127 for accessories. Furthermore, a data interface 129 (for example, one conforming to the RS485 standard) and a current supply connection 131 are arranged on the electronics housing 123.

[0024] There are also turbomolecular pumps that do not have this type of mounted electronics housing and are connected to external drive electronics.

[0025] The housing 119 of the turbomolecular pump 111 is provided with a ventilation intake 133, particularly in the form of a ventilation valve. The vacuum pump 111 may be vented via the ventilation intake 133. In the region of the lower portion 121, a sealing gas connection 135 (also referred to as a purge gas connection) is further arranged. Purge gas may be fed into the motor chamber 137 via the sealing gas connection 135 to protect the electric motor 125 (see, for example, FIG. 3) against the gas pumped by the pump. The electric motor 125 of the vacuum pump 111 is accommodated in the motor chamber 137. Two further coolant connections 139 are arranged on the lower portion 121. In this case, one coolant connection is provided as an intake for coolant, and the other coolant connection is provided as an exhaust outlet. Coolant can be introduced into the vacuum pump for cooling purposes. Other existing turbomolecular vacuum pumps (not shown) are operated exclusively by air cooling.

[0026] Since the lower surface 141 of the vacuum pump can be used as a base, the vacuum pump 111 may be operated in a vertical orientation with the lower surface 141 as the reference point. Furthermore, the vacuum pump 111 may be fixed to the recipient via the intake flange 113 and thus operated in a suspended state. Moreover, the vacuum pump 111 may be configured to operate even when it is aligned in a direction other than that shown in Figure 1. It is also possible to realize a vacuum pump configuration in which the lower surface 141 can be positioned sideways or upward instead of downward. In this case, in principle, any angle is possible.

[0027] In particular, other turbomolecular vacuum pumps (not shown) that are larger than the pump illustrated cannot be operated in a vertical configuration.

[0028] Various screws 143 are further positioned on the lower surface 141 shown in Figure 2. These screws 143 fasten components of the vacuum pump, which are not specifically identified here, to each other. For example, the bearing cover 145 is fixed to the lower surface 141.

[0029] The lower surface 141 is further provided with fixing holes 147. The pump 111 can be fixed to, for example, a mounting surface via these fixing holes 147. This is not possible with other turbomolecular vacuum pumps (not shown) that are larger than the pump shown.

[0030] Figures 2 to 5 show the coolant pipeline 148. Within the coolant pipeline 148, the coolant introduced and discharged via the coolant connection part 139 can be circulated.

[0031] As shown in the cross-sectional views of Figures 3 to 5, the vacuum pump has multiple process gas pump stages. The process gas pump stages are for pressurizing the process gas acting on the pump intake port 115 and sending it to the pump exhaust port 117.

[0032] A rotor 149 is positioned inside the housing 119. The rotor 149 has a rotor shaft 153 that is rotatable around a rotation axis 151.

[0033] The turbomolecular pump 111 has multiple turbomolecular pump stages connected in series to exert a pumping action. Each turbomolecular pump stage has multiple radial rotor blades 155 fixed to the rotor shaft 153, and multiple stator blades 157 positioned between the rotor blades 155 and fixed within the housing 119. In this case, one rotor blade 155 and one adjacent stator blade 157 each form one turbomolecular pump stage. The stator blades 157 are held apart from each other by spacer rings 159 at a desired axial distance.

[0034] The vacuum pump further comprises Holbeck pump stages arranged radially inward and outward from each other and connected in series to exert a pumping action. Another turbomolecular vacuum pump (not shown) exists that does not have Holbeck pump stages.

[0035] The rotor of the Holbeck pump stage has a rotor hub 161 positioned on the rotor shaft 153, and two cylindrical Holbeck rotor sleeves 163, 165 fixed to and supported by the rotor hub 161. The Holbeck rotor sleeves 163, 165 are oriented coaxially with respect to the axis of rotation 151 and are radially engaged with each other inward and outward. Two more cylindrical Holbeck status sleeves 167, 169 are provided. The Holbeck status sleeves 167, 169 are similarly oriented coaxially with respect to the axis of rotation 151 and are radially engaged with each other inward and outward.

[0036] The pumping surface of the Holbeck pump stage is formed by its sides, that is, by the radially inner and / or outer surfaces of the Holbeck rotor sleeves 163, 165 and the Holbeck status sleeves 167, 169. The radially inner surface of the outer Holbeck status sleeve 167 faces the radially outer surface of the outer Holbeck rotor sleeve 163, forming a radial Holbeck gap 171, and together with this outer surface, forms a first Holbeck pump stage that follows the turbomolecular pump. The radially inner surface of the outer Holbeck rotor sleeve 163 faces the radially outer surface of the inner Holbeck status sleeve 169, forming a radial Holbeck gap 173, and together with this outer surface, forms a second Holbeck pump stage. The radial inner surface of the inner Holbeck status sleeve 169 faces the radial outer surface of the inner Holbeck rotor sleeve 165, forming a radial Holbeck gap 175, and together with this outer surface, forms a third Holbeck pump stage.

[0037] A radially extending channel may be provided at the lower end of the Holbeck rotor sleeve 163. Through this channel, the radially outward-located Holbeck gap 171 is connected to the central Holbeck gap 173. A further radially extending channel may be provided at the upper end of the inner Holbeck stage sleeve 169. Through this channel, the central Holbeck gap 173 is connected to the radially inward-located Holbeck gap 175. This connects multiple Holbeck pump stages that engage with each other internally and externally in series. A further connecting channel 179 leading to the exhaust port 117 may be provided at the lower end of the radially inward-located Holbeck rotor sleeve 165.

[0038] The surfaces of the Holbeck status sleeves 167 and 169 that perform the aforementioned pumping action each have multiple Holbeck grooves that spiral around the rotation axis 151 and extend axially. On the other hand, the opposing sides of the Holbeck rotor sleeves 163 and 165 are smoothly formed and send the gas for operating the vacuum pump 111 forward within the Holbeck grooves.

[0039] For the rotatable support of the rotor shaft 153, a rolling bearing 181 is provided in the area of ​​the pump exhaust port 117, and a permanent magnet type magnetic bearing 183 is provided in the area of ​​the pump intake port 115.

[0040] In the region of the rolling bearing 181, a conical splash nut 185 is provided on the rotor shaft 153. The splash nut 185 has an outer diameter that increases toward the rolling bearing 181. The splash nut 185 is in sliding contact with at least one scraping member of the working medium reservoir. In other turbomolecular vacuum pumps (not shown), a splash screw may be provided instead of a splash nut. As a result, various configurations are possible, and in the above relationship, the term "splash tip" is also used.

[0041] The working medium storage unit has a plurality of absorbent disks 187 stacked vertically. These disks 187 are impregnated with a working medium for the rolling bearings 181, such as a lubricant.

[0042] During operation of the vacuum pump 111, the working fluid is transmitted by capillary action from the working fluid reservoir through the scraping member to the rotating splash nut 185, and then, based on centrifugal force, along the splash nut 185 toward the rolling bearing 181 toward the increasing outer diameter of the splash nut 185, where, for example, lubrication is performed. The rolling bearing 181 and the working fluid reservoir are surrounded within the vacuum pump by a tank-shaped insert 189 and a bearing cover 145.

[0043] The permanent magnet type magnetic bearing 183 has a rotor-side bearing half 191 and a stator-side bearing half 193. Each of these has one ring stack, which consists of multiple rings 195, 197 of permanent magnets stacked vertically in the axial direction. The ring magnets 195, 197 face each other, forming a radial bearing gap 199, in which case the rotor-side ring magnet 195 is positioned radially outward, and the stator-side ring magnet 197 is positioned radially inward. The magnetic field present in the bearing gap 199 causes a magnetic repulsive force between the ring magnets 195, 197. This repulsive force provides radial support for the rotor shaft 153. The rotor-side ring magnet 195 is supported by a support portion 201 of the rotor shaft 153. The support portion 201 surrounds the ring magnet 195 radially outward. The stator-side ring magnet 197 is supported by a support portion 203 of the stator side. The support portion 203 extends through the ring magnet 197 and is a radial support of the housing 119. Pillar It is suspended from 205. The rotor-side ring magnet 195 is fixed by a cover element 207 connected to the support portion 203, parallel to the rotation axis 151. The stator-side ring magnet 197 is connected to the support portion 203 in one direction parallel to the rotation axis 151. support The ring 209 is fixed by a fixing ring 211 which is coupled to the support portion 203. A disc spring 213 may be further provided between the fixing ring 211 and the ring magnet 197.

[0044] An emergency bearing or safety bearing 215 is provided within the magnetic bearing. The emergency bearing or safety bearing 215 rotates freely without contact during normal operation of the vacuum pump, and only engages when the rotor 149 is excessively displaced radially relative to the stator, thereby forming a radial stopper for the rotor 149 so as to prevent collision between the rotor-side structure and the stator-side structure. The safety bearing 215 is configured as a non-lubricated rolling bearing and forms a radial gap with the rotor 149 and / or stator. This gap prevents the safety bearing 215 from engaging during normal pump operation. The safety bearing 215 engages upon radial displacement, and since the radial displacement is sufficiently large, the safety bearing 215 does not engage during normal operation of the vacuum pump, and at the same time is sufficiently small so that collision between the rotor-side structure and the stator-side structure is prevented in all situations.

[0045] The vacuum pump 111 has an electric motor 125 that rotates the rotor 149. The armature of the electric motor 125 is formed by the rotor 149. The rotor shaft 153 of the rotor 149 extends through the motor stator 217. A permanent magnet assembly may be positioned radially outward or embedded in the portion of the rotor shaft 153 that extends through the motor stator 217. An intermediate chamber 219 is positioned between the motor stator 217 and the portion of the rotor 149 that extends through the motor stator 217. room 219 has a radial motor gap. Through the motor gap, the motor stator 217 and the permanent magnet assembly may magnetically influence each other to transmit drive torque.

[0046] The motor stator 217 is fixed within the housing, in a motor chamber 137 provided for the electric motor 125. A seal gas (also called a purge gas, which may be, for example, air or nitrogen) can reach the motor chamber 137 via a seal gas connection 135. The electric motor 125 can be protected from process gases, such as corrosive parts of the process gas, via the seal gas. The motor chamber 137 may be evacuated via a pump exhaust port 117. That is, a vacuum pressure, at least approximately, is acting within the motor chamber 137, achieved by an auxiliary vacuum pump connected to the pump exhaust port 117.

[0047] A so-called labyrinth seal 223, which is known in itself, may be further provided between the rotor hub 161 and the wall portion 221 that defines the motor chamber 137. This is particularly useful for the motor chamber relative to the Holbeck pump stage located radially outward. 137 A better seal is achieved.

[0048] Hereinafter, with reference to Figure 6, the internal Holbeck status leaf 10 configured according to the present invention will be described. The internal Holbeck status leaf 10 can be assembled to the turbomolecular vacuum pump 111 in place of the illustrated status leaf 169. Moreover, in this case, the rest of the structure of the turbomolecular vacuum pump 111 may be retained in the same way as the basic structure of the Holbeck pump stage having three pump stages located inside and outside.

[0049] In the embodiment shown in Figure 6, the inner status leaf 10 has a substantially hollow cylindrical form having a free end 16 and a fixed end 14 located axially opposite. The fixed end 14 is here attached to the fixed housing portion 12 of the vacuum pump 111, for example, by an interference fit. Even if this is not shown here in Figure 6, the status leaf 10 is concentrically surrounded by the rotor sleeve, forming a Holbeck gap. In other words, the status leaf 10 is located inside or is an inner status leaf 10.

[0050] As can be readily seen from the drawing in Figure 6, the status leaf 10 is configured in multiple parts or modularly, and in the embodiment shown herein, the status leaf 10 may be assumed to consist of three or more, for example, three, four or five or more sleeve parts, but is composed of a hollow cylindrical first sleeve part 18 and a hollow cylindrical second sleeve part 20. Although not shown herein, each of the individual sleeve parts 18, 20 has male threads, in which case the male threads of the first sleeve part 18 are different from the male threads of the second sleeve part 20 by at least one thread variable. Furthermore, the two sleeve parts 18, 20 may each have different axial lengths. The thread variables referred to may be, for example, the number of threads forming individual thread grooves across the groove bottom or outer surface of each sleeve part 18, 20, the thread pitch, the width of the thread groove, the width of the threads, and / or the height of the threads.

[0051] First sleeve section minute 1 8 is the first end Part 2 The first sleeve portion 18 has a first end 26 and a second end 24 located opposite to the first end 22. Correspondingly, the second sleeve portion 20 has a first end 26 and a second end 28 located opposite to the first end 26. In this case, the first end 22 of the first sleeve portion 18 is the end of the first sleeve portion 18 that is attached to the housing portion 12 in position and therefore corresponds to the fixed end 14 of the status sleeve 10. In contrast, the first end 26 of the second sleeve portion 20 is the end through which the second sleeve portion 20 is connected to the first sleeve portion 18 This is the end of the second sleeve portion 20, which is attached to the second end 24 of the status sleeve 10. Accordingly, the second end 28 of the second sleeve portion 20 forms the free end 16 of the status sleeve 10 when no other sleeve portion is connected to the second sleeve portion 20 in the axial direction.

[0052] Furthermore, as can be seen from Figure 6, the first ends 22 and 26 of the first sleeve portion 18 or the second sleeve portion 20 each form a stepped first end contour 30, and in this case, the first end contour 30 of the first sleeve portion 18 is formed identically to the first end contour 30 of the second sleeve portion 20. Correspondingly, the second ends 24 and 28 of the first sleeve portion 18 or the second sleeve portion 20 each form a stepped second end contour 32, and in this case, the second end contour 32 of the first sleeve portion 18 is formed identically to the second end contour 32 of the second sleeve portion 20. Therefore, except for the configuration of the male threads and, in some cases, the axially extended portions, the two sleeve portions 18 and 20 are essentially formed identically.

[0053] The first end contour 30 of the second sleeve portion 20 is configured to be essentially complementary to the second end contour 32 of the first sleeve portion 18, so that the second sleeve portion 20 can be attached to the first sleeve portion 18. Thus, the first end 26 of the second sleeve portion 20 fits into the second end 24 of the first sleeve portion 18 essentially on a shape-coupled basis.

[0054] In order to allow the arrangement of the two sleeve portions 18 and 20 to be swapped as needed, the first end contour 30 of the first sleeve portion 18 is the second end contour of the second sleeve portion 20 32 It is formed in an essentially complementary manner to the first sleeve portion. Therefore, the second sleeve portion 20 can be attached to the housing portion 12 in a fixed position via its first end contour portion 30, while in this case, the first sleeve portion 18 can be attached to the second end contour portion 32 of the second sleeve portion 20 via its first end contour portion 30.

[0055] As already mentioned, the two end contours 30 and 32 are formed in a stepped manner and have an annular first end face 34 and an annular second end face 36, respectively. The second end face 36 is recessed in the axial direction relative to the annular first end face 34. In this case ,circle Circular Second The end face 36 is the first end face of each end contour portion 30, 32. 34 The end face is recessed in the axial direction relative to the first end contour 30. However, in the first end contour 30, the annular first end face 34 surrounds the annular second end face 36, while in the second end contour 32, the annular second end face 36 surrounds the annular first end face 34 To surround.

[0056] Based on the fact that the radial positions of the two end faces 34 and 36 are swapped at the ends located on opposite sides of the respective sleeve portions 18 and 20, the first end contour portion 30 in each sleeve portion 18 and 20 First The distance between the end face 34 and the second end face 36 of the second end contour portion 32 is the same as the distance between the second end face 36 of the first end contour portion 30 and the first end face 34 of the second end contour portion 32.

[0057] As a result, based on the stepped configuration of the respective end contours 30 and 32 described above, the inner cylindrical surface 38 extends between the first end face 34 and the second end face 36 of the first end contour 30, while the outer cylindrical surface 40 extends between the first end face 34 and the end face 36 of the second end contour 32.

[0058] In this case, each cylindrical outer surface 40 may have a certain degree of radial over-dimension relative to each cylindrical inner surface 38, thereby allowing the sleeve portions 18 and 20 to be joined to each other by a press-fit joint acting along the two cylindrical surfaces 38 and 40. Alternatively, the inner surface 38 of each cylinder may be designed to have female threads, and the outer surface 40 of each cylinder to have male threads that match the female threads, thereby allowing the sleeve portions 18 and 20 to be screwed to each other.

[0059] With respect to the respective end contours 30 and 32, the sleeve portions 18 and 20 can be swapped with each other as needed, or, in some cases, replaced with appropriately configured sleeve portions having other Holbeck thread geometry, thereby increasing the degree of freedom in pump design with respect to characteristic values ​​such as pumping speed and / or compression performance and power consumption. Furthermore, while this application relates to the invention described in the claims, it also includes the following additional aspects. 1. A vacuum pump (111), in particular a turbomolecular vacuum pump (111), A Holbeck pump stage comprising a Holbeck stator and a Holbeck rotor, The Holbeck stator has a status leaf (10, 169), the status leaf (10, 169) having a fixed end (14) attached to the fixed housing portion (12) of the vacuum pump (11), and a free end (16) located axially opposite to the fixed end (14), In a vacuum pump (111), the Holbeck rotor has a rotor sleeve (163), the rotor sleeve (163) surrounds the status sleeves (10, 169) while forming a Holbeck gap (173), The vacuum pump (111) is characterized in that the status leaf (10, 169) is formed from multiple parts. 2. The vacuum pump (111) of the above-mentioned status sleeve (10, 169) comprises a first sleeve portion (18) having a first end (22) and a second end (24) located opposite to the first end (22), and at least one second sleeve portion (20) having a first end (26) and a second end (28) located opposite to the first end (26), wherein the first end (22) of the first sleeve portion (18) is attached to the housing portion (12) in a fixed position, and the first end (26) of the second sleeve portion (20) is attached to the second end (24) of the first sleeve portion (18). 3. The first end (22) of the first sleeve portion (18) has a first end contour (30), and the first end of the second sleeve portion (20) has a first end contour (30) corresponding to the first end contour (30) of the first sleeve portion (18), and / or The vacuum pump (111) according to the 1 or 2 above, characterized in that the second end (24) of the first sleeve portion (18) has a second end contour (32), and the second end (28) of the second sleeve portion (20) has a second end contour (32) corresponding to the second end contour (32) of the first sleeve portion (18). 4. The first end (22) of the first sleeve portion (18) has a first end contour (30), and the second end of the second sleeve portion (20) has a second end contour (32) formed complementary to the first end contour (30) of the first sleeve portion (18), and / or A vacuum pump (111) which is characterized in that the first end (26) of the second sleeve portion (20) has a first end contour (30), and the second end of the first sleeve portion (18) has a second end contour (32) formed complementary to the first end contour (30) of the second sleeve portion (20), any one of the above 1 to 3. 5. Each of the first end contours (30) has a first end face (34) and a second end face (36) that is axially recessed relative to the first end face (34), and / or The vacuum pump (111) according to the 3 or 4 above, characterized in that each of the second end contours (32) has a first end face (34) and a second end face (36) that is recessed in the axial direction relative to the first end face (34). 6. The vacuum pump (111) of the above 5, characterized in that the distance between the first end face (34) of the first end contour (30) and the second end face (36) of the second end contour (32) corresponds to the distance between the second end face (36) of the first end contour (30) and the first end face (34) of the second end contour (32). 7. The vacuum pump (111) according to 5 or 6, characterized in that the first end face (34) of the first end contour (30) is connected to the second end face (36) of the first end contour (30) via the inner cylindrical surface (38), and the first end face (34) of the second end contour (32) is connected to the second end face (36) of the second end contour (32) via the outer cylindrical surface (40) having a larger diameter than the inner cylindrical surface (38) of the first end contour (30). 8. A vacuum pump (111) which is any one of the above 1 to 7, characterized in that the status sleeve (10, 169) has male threads having a plurality of screw grooves, the screw grooves are defined by the threaded portion formed on the status sleeve (10, 169) and the groove bottom formed by the status sleeve (10, 169), the male threads of the first sleeve portion (18) differ from the male threads of the second sleeve portion (20) by at least one thread coefficient, and at least one thread coefficient is selected from the group of thread coefficients consisting of the number of threaded portions, the screw pitch, the width of the screw groove, and the width of the threaded portion and the height of the threaded portion on the groove bottom. [Explanation of Symbols]

[0060] 10 Status Leaves 12. Housing portion in its designated position 14 Fixed end 16. The end on the free side 18. First sleeve section 20 Second sleeve section 22 18 first end 24 18 second end 26 20 First end 28 20 second end 30 First end contour 32 Second end contour 34 First end face (annular) 36. Second end face (annular) 38. Inner surface of the cylinder 40 Cylindrical outer surface 111 Turbomolecular pump 113 Intake flange 115 Pump intake 117 Pump exhaust port 119 Housing 121 Lower part 123 Electronics Housing 125 Electric Motor 127 Accessory connection part 129 Data Interfaces 131 Current supply connection 133 Ventilation intake 135 Seal gas connection 137 Motor Room 139 Coolant connection part 141 Bottom surface 143 screws 145 Bearing cover 147 Fixed hole 148 Coolant piping 149 Rotor 151 Rotation axis 153 Rotor Shaft 155 Moving blade 157 Static Wing 159 Spacer Ring 161 Rotor Hub 163 Holbeck Rotor Sleeve 165 Holbeck Rotor Sleeve 167 Holbeck Status Leaf 169 Holbeck Status Leaf 171 Holbeck gap 173 Holbeck gap 175 Holbeck gap 179 connection channels 181 Rolling bearings 183 Permanent magnet type magnetic bearing 185 Splash Nut 187 discs 189 Inserts 191 Rotor-side bearing half 193 Stator-side bearing half 195 Ring Magnets 197 Ring Magnets 199 Bearing clearance 201 Support part 203 Support part 205 Radial support columns 207 cover elements 209 Support ring 211 Fixing ring 213 Disc spring 215 Emergency bearing or safety bearing 217 Motor Stator 219 Intermediate Room 221 Wall section 223 Labyrinth Seal

Claims

1. A vacuum pump (111), A Holbeck pump stage comprising a Holbeck stator and a Holbeck rotor, The Holbeck stator has a status leaf (10, 169), the status leaf (10, 169) having a fixed end (14) attached to the housing portion (12) in a fixed position of the vacuum pump (111), and a free end (16) located axially opposite to the fixed end (14), In a vacuum pump (111), the Holbeck rotor has a rotor sleeve (163), the rotor sleeve (163) surrounds the status sleeves (10, 169) while forming a Holbeck gap (173), The status sleeve (10, 169) comprises a first sleeve portion (18) having a first end (22) and a second end (24) located opposite to the first end (22), and at least one second sleeve portion (20) having a first end (26) and a second end (28) located opposite to the first end (26), wherein the first end (22) of the first sleeve portion (18) is attached to the housing portion (12) in a fixed position, and the first end (26) of the second sleeve portion (20) is attached to the second end (24) of the first sleeve portion (18), The first end portion (22) of the first sleeve portion (18) has a first end contour portion (30), The second end portion (24) of the first sleeve portion (18) has a second end contour portion (32), The first end portion (26) of the second sleeve portion (20) has a first end contour portion (30), The second end portion (28) of the second sleeve portion (20) has a second end contour portion (32), The first end contour portion (30) of the second sleeve portion (20) corresponds to the first end contour portion (30) of the first sleeve portion (18), The second end contour portion (32) of the second sleeve portion (20) corresponds to the second end contour portion (32) of the first sleeve portion (18), The second end contour portion (32) of the second sleeve portion (20) is formed complementaryly to the first end contour portion (30) of the first sleeve portion (18), A vacuum pump (111) characterized in that the second end contour portion (32) of the first sleeve portion (18) is formed complementaryly to the first end contour portion (30) of the second sleeve portion (20).

2. Each of the first end contours (30) has a first end face (34) and a second end face (36) that is recessed axially relative to the first end face (34), and / or The vacuum pump (111) according to claim 1, characterized in that each of the second end contours (32) has a first end face (34) and a second end face (36) that is recessed in the axial direction relative to the first end face (34).

3. The vacuum pump (111) according to claim 2, characterized in that the distance between the first end face (34) of the first end contour (30) and the second end face (36) of the second end contour (32) corresponds to the distance between the second end face (36) of the first end contour (30) and the first end face (34) of the second end contour (32).

4. The vacuum pump (111) according to claim 2, characterized in that the first end face (34) of the first end contour (30) is connected to the second end face (36) of the first end contour (30) via the inner cylindrical surface (38), and the first end face (34) of the second end contour (32) is connected to the second end face (36) of the second end contour (32) via the outer cylindrical surface (40) having a larger diameter than the inner cylindrical surface (38) of the first end contour (30).

5. The vacuum pump (111) according to claim 1, characterized in that the status sleeve (10, 169) has male threads having a plurality of screw grooves, the screw grooves are defined by the threaded portion formed on the status sleeve (10, 169) and the groove bottom formed by the status sleeve (10, 169), the male threads of the first sleeve portion (18) differ from the male threads of the second sleeve portion (20) by at least one thread coefficient, and the at least one thread coefficient is selected from the group of thread coefficients consisting of the number of threaded portions, the screw pitch, the width of the screw groove, and the width of the threaded portion and the height of the threaded portion on the groove bottom.

Images