JP2018084231A - Vacuum pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an improved vacuum pump having at least two inlets separated from each other, which provides a compact structural shape.SOLUTION: A vacuum pump, in particular a turbo molecular pump is provided that has a housing (11) having at least two inlets (15a, 15b) separated from each other, and that transports fluid toward an outlet by a pumping action of a stator and a rotor. In the vacuum pump, at least two inlets (15a, 15b) are provided in the housing (11) offset from each other as seen in the circumferential direction (U) of the rotor, and at least one plane (E1) transiting a rotating axis (21) in a direction perpendicular thereto transits through at least two inlets (15a, 15b).SELECTED DRAWING: Figure 7

Description

  The present invention relates to a vacuum pump, particularly a turbo molecular pump. The vacuum pump has a housing having at least two inlets separated from each other for connecting at least one receiver to at least one pump stage provided in the housing. The pump stage is for transporting fluid, in particular fluid drawn from the receiver, in the direction of the inlet of the vacuum pump provided in the housing. In this case, the pump stage has at least one rotor that can rotate with respect to the stator about the rotation axis. At that time, the stator and the rotor are formed so that they perform a pumping action when the rotor rotates. This conveys the fluid toward the outlet.

  Such vacuum pumps are known from the prior art. These are also referred to as split flow vacuum pumps or multi-inlet vacuum pumps. In such a vacuum pump having a plurality of inlets, there is a problem that these cannot be easily realized in a compact shape. This is because the multiple inlets require correspondingly large structural spaces in the housing of the vacuum pump.

International Publication No. 200404068099A1 European Patent Application Publication No. 2975268A2 Federal model of utility model No. 2013010204 European Patent Application Publication No. 1626179A2

  The present invention provides an improved vacuum pump having at least two inlets separated from each other, wherein the vacuum pump can be realized in a compact structural shape. The task is to do.

  This problem is solved by a vacuum pump having the features of claim 1. Preferred embodiments and developments of the invention are described in the dependent claims.

  A vacuum pump according to the invention, in particular a turbomolecular pump, preferably a split flow pump, has a housing with at least two inlets separated from each other for connection of at least one receiver, and is provided in the housing, At least one pump stage for transporting fluid, in particular fluid drawn from at least one receiver, in the direction of the outlet of a vacuum pump provided in the housing, wherein the pump stage is centered on the axis of rotation At least one rotor that is rotatable relative to the stator, wherein the stator and the rotor are configured so that they act as a pump as the rotor rotates, so that the fluid flows in the direction of the outlet It is conveyed to. In this case, at least two inlets are provided in the housing offset from each other when viewed in the circumferential direction of the rotor, and at least one plane that runs perpendicular to the axis of rotation passes through the at least two inlets. It has changed.

  In the vacuum pump according to the invention, the plane is perpendicular to the axis of rotation and also passes through both inlets or intersects both inlets, so that these inlets are in the housing of the vacuum pump. , At least essentially located at the same axial structural height. Therefore, unlike the arrangement of the inlets offset along the axial direction, the axial length of the vacuum pump according to the invention can be kept short. The vacuum pump according to the invention can thus be made compact, whereby a compact structural shape can be realized.

  The concepts “axial direction” and “axial direction” are matched to the direction of transition along the rotation axis. On the other hand, the concept of “circumferential direction” is matched to the direction of transition around the rotation axis in the peripheral direction.

  In the vacuum pump according to the invention, the main inlet may be provided in the housing in addition to the at least two inlets. Preferably, the main inlet is present at the axial end of the housing, in particular at the front of the housing located at the axial end. In this case, preferably, at least two inlets are not provided in front of the housing.

  The main inlet and the other inlet can in particular be a port of a vacuum pump. A container or a receiver to be evacuated can be connected to these.

  A plane that passes through at least two inlets preferably does not pass through the main inlet. At least two inlets are thus located offset relative to the main inlet, as viewed in the axial direction. The inlet is in particular a secondary inlet. In these, at least one pump stage exhibits a lower pumping action than the main inlet.

  The inlet is preferably located at the other axial end of the housing. This is opposite the axial end with the main inlet. The inlet can be provided on or formed on the peripheral surface of the housing. They are therefore preferably not located at the other axial end of the housing in front of the housing. Preferably, the main inlet is located at the upper axial end of the housing, especially at the upper front, while the inlet is located at the lower axial end of the housing.

  Each inlet has an inlet opening having a center. The inlet opening can be at least approximately circular, square or rectangular. Preferably, the plane transitions through the center of the inlet. Thus, the plurality of inlets are located at exactly the same structural height, which makes it possible to realize a particularly compact structural shape.

  It is possible that the plane does not pass through the center of at least one inlet. The center and thus the at least two inlets can thus have at least a slight deviation when viewed in the axial direction. The axial deviation of the two inlets is then preferably less than the sum of the radii of both inlets. Since the inlet is therefore at least essentially at the same axial height, if not accurate, a compact and short structural shape of the vacuum pump can be realized.

  Preferably, each inlet opening has a predetermined area. In so doing, at least 25%, preferably at least 30%, more preferably at least 40%, and even more preferably at least 50% of the area of the inlet opening is located at the same axial height as viewed in the axial direction. ing. Therefore, the overlap of the inlet opening partly occurs in the axial direction. This achieves that the inlet opening is located at least essentially at the same axial structural height, and the vacuum pump can be realized with a compact structural shape.

  The inlet (s) can be connected to or in fluid connection with the pump stage so that different pressure levels are generated at the inlet. The pump stage thus performs different pumping actions at the plurality of inlets.

  Alternatively, the inlet (s) can be connected to the pump stage such that at least approximately the same pressure level is generated at the inlet, or can be in fluid connection with the pump stage. Is possible.

  The plane across the inlet can also move through the outlet of the vacuum pump. The inlet is thus at least essentially at the same axial structural height as the outlet. This makes it possible to realize a sink pump structure that is particularly compact and short in the axial direction. The outlet is then arranged or formed in the housing, shifted in the direction of the inlet as viewed in the circumferential direction. Preferably, the outlet is present between at least two inlets when viewed in the circumferential direction. The outlet can have a circular, square, or rectangular outlet opening.

  In particular, the outlet opening has one center. The plane can pass through the center of the inlet opening and through the center of the outlet opening. This makes it possible to realize that the outlet and the inlet are located at the same axial height. The compactness can be further improved thereby. However, at least slight axial deviations between the centers described above can also be contemplated.

  The vacuum pump can have at least one Holbeck pump stage. In this case, at least two inlets open into the Holbeck pump stage. The inlet can thus be fluidly connected to or coupled to the Holbeck pump stage.

  The arrangement of a plurality of inlets at least at essentially the same axial structural height of the vacuum pump can be realized particularly simply under the use of a Holbeck pump stage. This is because the connection between the inlet and the Holbeck pump stage can be realized in a particularly simple manner, for example by a channel extending radially inward from the housing outer surface to the Holbeck gap of the Holbeck pump stage. Because it is possible. Moreover, different pressure levels at the multiple inlets can be easily realized.

  Preferably, the Holbeck pump stage is a Holbeck pump stage located radially outward of at least two Holbeck pump stages nested together.

  The vacuum pump can have at least one turbomolecular pump stage. In so doing, it is possible for at least two inlets to open into the turbomolecular pump stage. The inlet can thus be fluidly connected or coupled directly with the turbomolecular pump stage. This allows a lower pressure level to be realized in the plurality of inlets, especially compared to the connection of the inlet to the Holbeck pump stage.

  At least one turbomolecular pump stage is pre-connected in the vacuum pump, preferably to at least one Holbeck pump stage. That is, the fluid conveyed into the vacuum pump via the main inlet first flows through the turbomolecular pump stage and then through the Holbeck pump stage for the first time. The pump channel extending between the main inlet and the outlet thus travels first through the turbomolecular pump stage and then through the Holbeck pump stage. The secondary inlet opens into the pump channel, for example, in the region of the turbomolecular pump stage or in the region of the Holbeck pump stage.

  The inlet is preferably not an intermediate suction inlet used to evacuate the volume of the vacuum pump between the inner and outer seals.

  The invention also relates to a receiver for connection to a vacuum pump according to the invention. The receiver then has at least two outlets. These are formed for connection to at least two inlets of the vacuum pump and are provided in the receiver housing. The outlets are spaced from one another in the circumferential direction of the receiver, corresponding to the inlet of the vacuum pump, and are at least essentially at the same axial structural height. The receiver can thus be made compact as well.

  The invention furthermore relates to a vacuum system comprising at least one vacuum pump according to the invention and at least one receiver. The receiver is connected to a vacuum pump, in which a vacuum seal, in particular an O-ring, is provided or provided for sealing the vacuum connection between the receiver outlet and the vacuum pump inlet. The seal can have different thicknesses. This is to perform tolerance compensation.

  In the following, the invention will be described by way of example on the basis of advantageous embodiments with reference to the accompanying drawings.

Perspective view of turbo molecular pump Bottom view of turbo molecular pump Sectional view of the turbomolecular pump along section line AA shown in FIG. Sectional view of the turbomolecular pump along section line BB shown in FIG. Sectional view of the turbomolecular pump along the section line CC shown in FIG. Cross section of the vacuum pump according to the invention Side view of another vacuum pump according to the invention Side view of yet another vacuum pump according to the invention Cross section of the vacuum pump according to the invention

  The turbomolecular pump 111 shown in FIG. 1 has a pump inlet 115 surrounded by an inlet flange 113. A receiver (not shown) can be connected to the pump inlet by a known method. Gas from the receiver can be aspirated from the receiver via pump inlet 115 and conveyed through the pump to pump outlet 117. A vacuum pump (such as a rotary pump (German: Drehschieberpumpe)) can be connected to the pump outlet.

  The inlet flange 113 forms the upper end of the housing 119 of the vacuum pump 111 in the direction of the vacuum pump of FIG. The housing 119 has a lower portion 121. This is provided with an electronics housing 123 from the side. The electronics housing 123 houses components of an electrical or electronic vacuum pump, for example for the operation of an electric motor 125 arranged in the vacuum pump. The electronics housing 123 is provided with a plurality of connecting portions 127 for accessories. Further, for example, a data interface 129 according to the RS485 standard and a power supply connection portion 131 are provided in the electronics housing 123.

  The housing 119 of the turbomolecular pump 111 is provided with a flood inlet 133 in the form of a flood valve (German: Flutventil). Through this, the vacuum pump 111 can be injected all at once (German: geflut worden). In the region of the lower part 121, another seal gas connection part 135 (also referred to as a cleaning gas connection part (also referred to as German) is provided). Through this, the cleaning gas is stored in the motor chamber 137 (in which the electric motor 125 is stored in the vacuum pump 111) before the gas conveyed by the pump to protect the electric motor 125 (see, for example, FIG. 3). Can be carried in). Two cooling medium connection portions 139 are further provided in the lower portion 125. In this case, one cooling medium connection is provided as an inlet for the cooling medium, and the other cooling medium connection is provided as an outlet. The cooling medium can be introduced into the vacuum pump for cooling purposes.

  Since the lower surface 141 of the vacuum pump can be used as a standing surface, the vacuum pump 111 can be operated upright on the lower surface 141. The vacuum pump 111 can be fixed to the receiver via the inlet flange 113, and can be operated by being suspended (or suspended, German). Moreover, the vacuum pump 111 can be configured to be actuated when configured in a different manner than that shown in FIG. It is also possible to implement an embodiment of the vacuum pump in which the lower side 141 is not provided facing down, but is oriented sideways or facing up.

  Several screws 143 are provided on the lower surface 141 shown in FIG. By these, the members of the vacuum pump not specified in detail here are fixed to each other. For example, the support cover 145 is fixed to the lower surface 141.

  The lower side surface 141 is further provided with a plurality of fixing holes 147. The pump 111 can be fixed to the contact surface, for example, via these.

  A cooling medium pipe 148 is shown in FIGS. Through this, the cooling medium introduced and led out via the cooling medium connection 139 can be circulated.

  As shown in the cross-sectional views of FIGS. 3-5, the vacuum pump has a plurality of process gas stages for conveying process gas that spans the pump inlet 115 to the pump outlet 117.

  A rotor 149 is disposed in the housing 119. This has a rotor shaft 153 that can rotate about a rotating shaft 151.

  The turbo molecular pump 111 has a plurality of pump stages connected in series to each other and performing a pumping action. These pump stages have a plurality of radial rotor disks 155 fixed to the rotor shaft 153 and a plurality of rotor disks 157 disposed between the rotor disks 155 and fixed in the housing 119. In this case, one rotor disk 155 and the adjacent stator disk 157 form one turbomolecular pump stage. The stator disks 157 are held together at a desired axial interval by spacer rings 159.

  In addition, the vacuum pump 111 has a plurality of Holbeck pump stages that are radially nested and connected to each other and serially connected to each other to perform a pumping action. The rotor of the Holbeck pump stage includes a rotor hub 161 provided on the rotor shaft 153, and two holbeck rotor sleeves 163 and 165 fixed to and supported by the rotor hub 161. These are coaxially connected to the rotating shaft 151 and are connected to each other in the radial direction. Further, two holbek stator sleeves 167.169 having a cylinder side surface shape are provided. These are similarly coaxial with respect to the rotary shaft 151 and are connected in a nested manner in the radial direction.

  The pumping surface of the Holbeck pump stage is formed by the side surfaces, that is by the radially inner and / or outer surfaces of the Holbeck rotor sleeves 163, 165 and the Holbeck stator sleeves 167, 169. The radially inner surface of the outer Holbeck stator sleeve 167 faces the radially outer surface of the outer Holbeck rotor sleeve 163, forming a radial Holbeck gap 171, and this is a turbomolecular pump A first Holbeck pump stage connected after the stage is formed. The radially inner surface of the outer Holbeck rotor sleeve 163 faces the radially outer surface of the inner Holbeck stator sleeve 169, forming a radial Holbeck gap 173, and this and the second Holbeck pump Form a step. The radially inner surface of the inner holbeck stator sleeve 169 faces the radially outer surface of the inner holbeck rotor sleeve 165, forming a radial holbeck gap 175, and this and the third holbeck Form a pump stage.

  The lower end of the Holbeck rotor sleeve 163 can be provided with a channel that moves in the radial direction. Through this, the Holbeck gap 171 located radially outward is connected to the central Holbeck gap 173. Furthermore, the upper end of the inner Holbeck stator sleeve 169 can be provided with a channel that moves in the radial direction. Through this, the central Holbeck gap 173 is connected to the Holbeck gap 175 located radially inward. Thereby, a plurality of Holbeck pump stages connected in a nested manner are serially connected to each other. A connecting channel 179 to the outlet 117 can be further provided at the lower end of the Holbeck rotor sleeve 165 located radially inward.

  The above-described surfaces of the Holbeck stator sleeves 163 and 165 that have a pumping effect have a plurality of Holbeck grooves that spiral around the rotating shaft 151 and change in the axial direction. On the other hand, the opposite sides of the Holbeck rotor sleeves 163, 165 are smooth and promote gas into the Holbeck groove for operating the vacuum pump 111.

  For the rotatable support of the rotor shaft 153, a roller bearing 181 is provided in the area of the pump outlet 171 and a permanent magnet bearing 183 is provided in the area of the pump inlet 115.

  In the region of the roller bearing 181, a conical splash nut 185 is provided on the rotor shaft 153. This has an outer diameter that increases towards the roller bearing 181. Splash nut 185 is in sliding contact with at least one skimmer in the operating medium reservoir. The operating medium reservoir has a plurality of absorbent disks 187 stacked on top of each other. These are impregnated with an operating medium for the roller bearing 181, for example, a lubricating medium.

  During operation of the vacuum pump 111, the operating medium is sent from the operating medium reservoir to the rotating splash nut 185 by way of the capillary effect through the skimmer, and centrifugal force causes the splash nut 185 to grow along the splash nut 185. In the direction of the outer diameter, it is conveyed toward the roller bearing 181 where it exhibits a lubricating function, for example. The roller bearing 181 and the operating medium reservoir are surrounded by the tank-shaped insert 189 and the bearing cover 145 in the vacuum pump.

  The permanent magnet bearing 183 has a rotor-side bearing half 191 and a stator-side bearing half 193. Each of these has one ring stack. The ring stack includes a plurality of permanent magnet rings 195 and 197 stacked in the axial direction. The ring magnets 195 and 197 face each other while forming a radial bearing gap 199. At this time, the ring magnet 195 on the rotor side is radially outward and the ring magnet 197 on the stator side is radially inward. Are arranged (provided). The magnetic field existing in the bearing gap 199 causes a magnetic repulsive force between the ring magnets 195 and 197. This provides radial support for the rotor shaft 153. The rotor-side ring magnet 195 is supported by the carrier portion 201 of the rotor shaft 153. This rotor shaft surrounds the ring magnet 195 radially outward. The stator side ring magnet 197 is carried by the stator side carrier portion 203. This carrier portion extends through the ring magnet 197 and is hung on the radial strut 205 of the housing 119. In parallel with the rotating shaft 151, the rotor-side ring magnet 195 is fixed by a cover element 207 connected to the carrier portion 203. The ring magnet 197 on the stator side is fixed in one direction parallel to the rotation shaft 151 by a direction passing through the fixing ring 209 connected to the carrier portion 203 and by a fixing ring 211 connected to the carrier portion 203. Yes. Between the fixing ring 211 and the ring magnet 197, a spring spring 213 can be further provided.

  An emergency or plan urine support 215 is provided inside the magnet support. This is the non-contact idling during normal operation of the vacuum pump 11 and the first engagement with the rotor 149 when it is biased radially with respect to the stator, the radial direction for the rotor 149. Form a stopper. This is because the structure on the rotor side is prevented from colliding with the structure on the stator side. The safety bearing 215 is formed as an unlubricated roller bearing and forms a radial gap with the rotor 149 and / or the stator. This realizes that the safety bearing 215 is not engaged during normal pump operation. The radial deviation when the safety support 215 is engaged is dimensioned sufficiently large so that the safety support 215 does not engage during normal operation of the vacuum pump and at the same time Since it is dimensioned sufficiently small, the rotor side structure is prevented from colliding with the stator side structure in all situations.

  The vacuum pump 111 has an electric motor 125 for rotating the rotor 149. An anchor (ankle, German: Anker) of the transmission motor 125 is formed by a rotor 149. The rotor shaft 153 extends through the motor stator 217. A portion of the rotor shaft 153 extending through the motor stator 217 can be provided with a permanent magnet device radially outward or embedded. An intermediate space 219 is provided between the motor stator 217 and the portion of the rotor 149 extending through the motor stator 217. This has a radial motor gap. Through this, the motor stator 217 and the permanent magnet device can be magnetically influenced to transmit the driving torque.

  The motor stator 217 is fixed inside a motor chamber 137 provided for the electric motor 125 in the housing. A seal gas (also called a cleaning gas, which can be air or nitrogen, for example) reaches the motor chamber 137 via the seal gas connection part 135. Via the sealing gas, the electric motor 125 can be protected from the process gas, for example from the corrosive parts of the process gas. The motor chamber 137 can be evacuated via a pump outlet 117. That is, the inside of the motor chamber 137 is at least approximately the vacuum pressure realized by the pre-vacuum pump connected to the pump outlet 117.

  In addition, a so-called known labyrinth hub 223 can be provided between the rotor hub 161 and the wall portion 221 that bounds the motor chamber 137. This is in particular to achieve a better sealing of the motor chamber 217 for the Holbeck pump stage located radially outward.

  Since the vacuum pump 111 described above can be formed as a split flow vacuum pump, this is a pump inlet 115 used as the main inlet (which is formed on the front face above the pump 111). In addition, it has two or more additional inlets (not shown in FIGS. 1 to 5) that are used as secondary inlets. These sub inlets are provided on or formed on the peripheral surface of the vacuum pump 111 or the housing 119 (including the lower portion 121).

  In accordance with the invention, at least two secondary inlets are provided in the housing 119 (also having a lower part 121) offset from one another in the circumferential direction of the rotor shaft 153 and transition perpendicular to the rotating shaft or rotating shaft 151 , At least one plane (not shown in FIGS. 1 to 5) travels through the secondary inlet. Therefore, the sub inlet is at least basically positioned at the same axial structural height with respect to the longitudinal direction of the rotating shaft 151. As a result, the vacuum pump 111 can be made compact or relatively short despite the sub-inlet. This is particularly the case compared to arrangements or devices in which the secondary inlets are arranged or formed offset from one another in the longitudinal direction of the rotary shaft 151. The secondary inlet then opens into the Holbeck gap 171 located radially outward. Alternatively, the secondary inlet can open into the pump channel in one of the plurality of turbomolecular pump stages or elsewhere.

  The vacuum pump 33 shown as a pure simplified sectional view in FIG. This can be provided with a lower part 121 in the form of a housing 119. The vacuum pump 33 has at least two other inlets 15 in addition to the main inlet 13. Of these, only one inlet 15 can be seen in FIG. The inlet 15 is used as a secondary inlet. Each inlet 13, 15 can be connected to the outlet of a receiver (not shown). This is because the receiver is evacuated through the pump 33.

  Furthermore, at least one pump stage 17 is formed in the housing 11. This can be, for example, at least one turbomolecular pump stage, a Holbeck pump stage, or a combination of a turbomolecular pump stage and a subsequent Holbeck pump stage. The pump stage 17 has a rotor 19 (see the rotor 149 described above). This rotor can rotate a rotating shaft or rotating shaft 21 with respect to a stator (not shown). This is to generate a pump action. Due to the pumping action, a fluid (such as process gas or air) can be transported into the pump from a receiver or from a plurality of connected receivers via a plurality of inlets 13,15. And can be pumped through the pump to its outlet (not shown, see pump outlet 117 in FIG. 1). From there it can be further pumped, for example by a pre-vacuum pump.

  In the vacuum pump 33 of FIG. 6, at least two inlets 15 are located apart from the main inlet 13, and are particularly offset in the housing 11 in the rotational direction U of the rotor 19. In this case, at least one plane E1 moves perpendicularly to the rotation axis 21 and through at least two inlets 15. With respect to the rotary shaft 21, both inlets 15 are thus located at the same axial structural height of the vacuum pump 33, which allows a compact and short formation of the vacuum pump 33.

  Further, as shown in FIG. 6, the plane E <b> 1 transitions through the main inlet 13. At least one other plane E2, which runs perpendicular to the rotation axis 21 and is axially offset with respect to the plane E1, intersects the main inlet 13.

  The vacuum pump shown as a side view in FIG. 7 has a housing 11 with an upper housing part 23 and a lower housing part 25. Inside the housing, the vacuum pump of FIG. 7 is configured like the pump of FIG. Furthermore, a main inlet (not shown) can be provided in the upper housing part 23. For example, it can be provided in the same manner as in the vacuum pumps 1 to 5 of FIGS.

  The vacuum pump of FIG. 7 has two inlets 15a and 15b. These are offset in the circumferential direction U of the rotor 19 and are provided in the lower housing portion 25. At that time, the plane E1 which moves perpendicularly to the rotating shaft 21 moves through both inlets 15a and 15b.

  As shown, both inlets 15a, 15b have a circular cross section with each center M1 or M2. The plane E1 travels through both centers M1 and M2. As a result, the centers M1 and M2 are at the same structural height in the axial direction with respect to the rotary shaft 21.

  Alternatively, the centers M1 and M2 have a slight axial offset when viewed in the axial direction. At such an axial offset, the plane E1 does not transit both centers M1 and M2 at the same time, but indeed indeed crosses both inlets 15a, 15b. Inlets 15a, 15b thus have slightly different axial heights.

  The vacuum pump of FIG. 8 is configured like the vacuum pump of FIG. However, in the vacuum pump of FIG. 8, the outlet 27 is located between both inlets 15a and 15b when viewed in the circumferential direction U. The outlet 27 has a circular outlet opening. The plane E1 changes through the center M3. The same applies to the centers M1 and M2 of the inlet openings of the inlets 15a and 15b. The outlet 27 has the same structural height in the axial direction as both the inlets 15a and 15b.

  The vacuum system 31 of FIG. 9 includes a vacuum pump 33 as described above and a receiver 35 having chambers 37 and 39. The chamber 37 is connected to the main inlet 13 of the vacuum pump 33 in a vacuum-tight manner. On the other hand, the other chamber 39 is vacuum-tightly connected to the sub inlet 15. Another chamber (not shown) of the receiver 35 is connected to another sub-inlet 15b (not shown in FIG. 9) in a vacuum-tight manner.

  As shown in FIG. 9, the chamber 37 slightly protrudes from the chamber 39 in the radial direction with respect to the rotation axis 21. To compensate for this protrusion or to compensate for other tolerances, a thick seal 41, in particular an O-ring seal, can be inserted between the outlet of the chamber 39 and the inlet 15a. On the other hand, a thin seal 43, in particular an O-ring seal, is arranged between the outlet of the chamber 37 and the main inlet 13.

  The described vacuum pump allows a compact structure. This is because the sub-inlets 15, 15a, 15b are basically arranged at the same structural height in the axial direction. The sub-inlets 15, 15a, 15b can then be connected to the pump stage so that different pressure levels act in the inlet during pump operation.

11 Housing 13 Main inlet 15 Sub inlet 15a Sub inlet 15b Sub inlet 17 Pump stage 19 Rotor 21 Rotating shaft 23 Upper housing part 25 Lower housing part 27 Outlet 31 Vacuum system 33 Vacuum pump 35 Receiver 37 Chamber 39 Chamber 41 Seal 43 Seal 111 Turbo molecular pump 113 Inlet flange 115 Pump inlet 117 Pump outlet 119 Housing 121 Lower part 123 Electronics housing 125 Electric motor 127 Accessory connection 129 Data interface 131 Power supply connection 133 Flood inlet (German: Fluteinlass)
135 Seal gas connection part 137 Motor chamber 139 Cooling medium connection part 141 Lower side surface 143 Screw 145 Bearing cover 147 Fixing hole 148 Cooling medium pipe 149 Rotor 151 Rotating shaft 153 Rotor shaft 155 Rotor disk 157 Stator disk 159 Spacer ring 161 Rotor blade part 163 Holbeck rotor sleeve 165 Holbeck rotor sleeve 167 Holbeck stator sleeve 169 Holbeck stator sleeve 171 Holbeck gap 173 Holbeck gap 175 Holbeck gap 179 Connection channel 181 Roller bearing 183 Permanent magnet bearing 185 Splash nut 187 Disc 189 Insert 191 Rotor Side bearing half 193 Rotor side bearing half 195 Ring magnet 197 Ring Magnet 199 Bearing gap 201 Carrier portion 203 Carrier portion 205 Radial column 207 Cover element 209 Support ring 211 Fixing ring 213 Belleville spring 215 Emergency or safety support portion 217 Motor stator 219 Intermediate space 221 Wall portion 223 Labyrinth seal U Circumferential direction E1 plane E2 plane M1 center M2 center M3 center

Claims (11)

Vacuum pumps, especially turbo molecular pumps,
A housing (11, 119, 121) having at least two inlets (15, 15a, 15b) separate from each other for connecting at least one receiver (35);
Housing (11,119) for transporting fluid, in particular fluid drawn from at least one receiver (35), in the direction of the outlet (27,117) of a vacuum pump provided in the housing (11,119,121). , 121) having at least one pump stage (17) provided in
In this case, the pump stage (17) has at least one rotor (19, 149) that is rotatable about the rotation axis (21, 151) with respect to the stator, in which case the stator and rotor (19, 149) is provided so as to exert a pump action in the rotor (19, 149) in which they rotate, and in this vacuum pump the fluid is conveyed in the direction of the outlet (27, 117) by this pump action,
At least two inlets (15, 15a, 15b) are provided in the housing (11, 119, 121) offset from each other when viewed in the circumferential direction (U) of the rotor (19, 149), and the rotating shaft A vacuum pump characterized in that at least one plane (E1) transitioning perpendicular to (21,151) transitions through at least two inlets (15, 15a, 15b). A main inlet (13, 115) is additionally provided in the housing (11, 119, 121) with respect to at least two inlets (15, 15a, 15b), in particular the housing (11, 119, 121). 2. The vacuum pump according to claim 1, wherein the flat surface (E 1) transitions without passing through the main inlet (13, 115). Each inlet (15, 15a, 15b) has a center (M1, M2), in particular a circular inlet opening, where the plane (E1) is the center of the inlet (15, 15a, 15b) 3. A vacuum pump according to claim 1 or 2, characterized by transitioning through (M1, M2). Each inlet (15, 15a, 15b) has a center (M1, M2), in particular a circular inlet opening, where the plane (E1) is at least of the plane (15, 15a, 15b). The vacuum pump according to claim 1 or 2, wherein the vacuum pump does not pass through one center (M1, M2). Each inlet (15, 15a, 15b) has a particularly circular inlet opening, in which case each inlet opening (15, 15a, 15b) has a predetermined area and in that case the inlet At least 25%, preferably 30%, more preferably 40%, even more preferably 50% of the area of the opening is located at the same axial height when viewed in the axial direction The vacuum pump as described in any one of Claim 1 to 4. The inlets (15, 15a, 15b) are connected to the pump stage (17) so that different pressure levels can be generated in the inlets (15, 15a, 15b) or at least approximately the same pressure level can be generated. The vacuum pump according to any one of claims 1 to 5, wherein the vacuum pump is provided. The vacuum pump according to any one of claims 1 to 6, characterized in that the plane (E1) transitions through the outlet (27, 117). These have at least one Holbeck pump stage (163, 165, 167, 169), in which at least two inlets (15, 15a, 15b) have a Holbeck pump stage (163, 165, 167, 169). The vacuum pump according to any one of claims 1 to 7, wherein the vacuum pump is opened into the inside. These have at least one turbomolecular pump stage (155,157), with at least two inlets (15,15a, 15b) opening into the turbomolecular pump stage (155,157) The vacuum pump according to any one of claims 1 to 8, wherein: The receiver (35) has at least two outlets, which are formed for connection to at least two inlets (15, 15a, 15b) of the vacuum pump (33) and the housing of the receiver (35) Receiver (35) for connection to a vacuum pump according to any one of the preceding claims, characterized in that it is provided on the receiver. A vacuum system comprising at least one vacuum pump (33) according to any one of claims 1 to 9 and at least one receiver (35) according to claim 10 connected to the vacuum pump (33). (31), in which case the vacuum seal (41) is used to seal the vacuum connection between the outlet of the receiver (33) and the inlet (13, 15, 15a, 15b) of the vacuum pump (33). 43), in particular O-ring seals, which are preferably of different thickness, (31).

Images