JP7018114B2 - How to make a vacuum pump - Google Patents

Description

INDUSTRIAL APPLICABILITY The present invention is a method for manufacturing a vacuum pump, particularly a turbo molecular vacuum pump, wherein the vacuum pump has at least one ring-shaped stator disk, and the stator disk is a rotor of a pump, particularly at least one. It relates to one in which the stator disk is set to work with one rotor disk to generate pumping action and the stator disk has at least two separate partial rings.

The present invention has at least one ring-shaped stator disk, the stator disk being set to work with at least one rotor disk of the pump to generate pumping action, and at least two stator disks. Also relevant are vacuum pumps with separate partial rings, especially turbo molecular vacuum pumps.

For example, in a turbomolecular vacuum pump, a plurality of rotor disks and stator disks are typically arranged alternately in the axial direction with respect to the rotation axis of the rotor of the pump. In this case, the stator disc is usually configured to consist of two partial rings extending about 180 ° about the rotation axis of the rotor of the turbo molecular vacuum pump, respectively. It is used for simplified assembly of stator discs. Therefore, these partial rings can be introduced from outside in the radial direction into the intermediate space between two adjacent rotor discs and assembled into a stator disc.

In order to separate the stator disc into the partial ring, for example, it is known that the stator disc having a pump active blade structure is separated as a member in advance, particularly after being manufactured by machining, by a hand-held tool. .. The manual process involves high inaccuracies and the risk of indefinite burr formation and workpiece deformation.

Other known methods attempt to separate the stator discs by wire erosion after manufacturing the stator discs with the blade structure. Wire erosion constitutes additional work steps, requires complex equipment, and has high cost and lead time.

An object of the present invention is to particularly simplify the manufacture of a vacuum pump.

This problem is solved by the method according to claim 1. According to this, in the first process portion, at least two stator disk partial rings are as follows, i.e., the partial ring comprises at least one pump active structure after the first process portion. The joints that are bonded to the member and between the partial rings have a locally reduced material thickness, so that the joints are manufactured together to form a planned separation point, and It is intended that the partial ring be separated at the planned separation point in a second process part separate from the first process part.

That is, the joints initially maintain the partial ring as a set of at least two partial rings. The partial rings can later be separated from each other at any time. The planned separation points allow the separation to take place independently of the formation of the blade structure of the partial ring or independent of the first process portion. That is, this method allows for particularly easy handling of the partial ring in the manufacturing process of the pump, the partial ring must be separated only when necessary, eg just before assembly. The manufacturing process is simplified as a whole because the separation is particularly easy based on the planned separation points.

The independence of separation from the first process part means that either a different tool and / or a different machine may be used for the separation, in particular to form the pump active structure. Thus, the tool or machine only needs to be able to separate the partial rings, in which way it can be formed obviously easier and smaller. Particularly preferably, since the separation is done by hand, no additional tools or machines are required for the separation. Hand separability can be easily assured by the appropriate dimensional setting of the material thickness or the shape of the joint.

Separation at the planned separation site means the final separation of the partial ring, especially by breaking the joint or the material constituting the planned separation site after the first process portion. Thus, the second process portion comprises the final separation of the partial ring, i.e., the partial ring is no longer coupled to one member after the second process portion. Basically, the first process part may also include, for example, measures to prepare the final separation, which may include, for example, locally reducing the material of the partial ring bonded to one member. For example, it is done by making a notch to form a planned separation point.

It should be understood that a stator disk is generally at least a substantially disk-like component of a pump, which remains static with respect to the pump housing during pump operation and is a pump active structure. To prepare for.

It should be understood that a partial ring is basically an element with a pumping active structure suitable for cooperating with a rotor, especially a rotor disk, to generate pumping action. That is, the formation of a partial ring involves at least the formation of a pump active structure. In this case, the pump active structure can be formed, for example, in a fully completed state before the second process part, or basically even more after the first process part or the second process part. Another process part in the later pump active structure can be done.

The pump-active structure is preferably molecularly pump-active. The pump active structure can be, for example, a turbo blade structure or a Ziegburn structure. The rotor or rotor disk generally comprises a structure corresponding to the pumping active structure of the stator disk to the extent that both of these structures exert pumping action due to their relative motion during rotor rotation. When the stator disc is a turbo molecular stator disc, the rotor or rotor disc particularly comprises a turbo blade structure as well. If the stator disc is, for example, a Ziegburn stator disc, the rotor or rotor disc comprises a substantially smooth and / or flat surface specifically facing the pump active structure of the stator disc.

According to a preferred embodiment, it is intended that the partial ring is manufactured in a completely finished state except for its joints prior to separation. This allows, in particular, the partial ring to be separated by the assembler only, especially shortly before assembly. In particular, such assembly involves the radial introduction of a partial ring into the intermediate space between the two rotor discs, as previously described in connection with the turbostator discs exemplary. Therefore, handling in the pre-assembly stage is particularly easy.

Scheduled separation points can include, for example, at least planned fracture points, material bridges and / or notches. The partial ring can be advantageously broken for separation, for example. Fracture, on the other hand, constitutes a particularly simple possibility for separating partial rings, with no special tools and / or special precision requirements, especially based on the planned break location. In addition, fracture provides the special advantage that the fractured part, i.e., the partial ring, is then precisely fitted and precisely aligned with each other in the assembled state, which is typical. Based on the fracture edge that corresponds exactly to.

For example, the joint or planned separation can be provided with a material thickness of up to 1 mm, especially within the minimum dimensions of the fracture direction and / or the cross section of the joint. Generally preferably, the material bridges at the joints are small, especially fragile, preferably small enough to be broken by hand. In general, material bridges can be formed, for example, as a particularly fragile bonded web.

In general, the turbomolecular stator disk and / or the turbomolecular stator disk partial ring can include, for example, an inner ring and / or an outer ring. From the inner ring, a plurality of stator blades extend radially outward, and from the outer ring, a plurality of stator blades extend radially inward. If both the inner and outer rings are provided, multiple stator blades extend radially between the inner and seven side rings.

The joint between the partial rings that make up the planned separation can preferably join the inner or outer ring of one partial ring to the inner or outer ring of the other partial ring, especially the blade. In particular, the material bridge at the joint is attached to at least one inner and / or outer ring of the partial ring, but not specifically to the blade. Material bridges have a significantly reduced material thickness, especially with respect to the inner or outer rings.

According to the evolution, it is intended that the partial ring be separated by hand and / or without tools, especially before assembling the partial ring to the stator disc by the assembler. The process is particularly simple, as no tools and / or machines are required for separation.

The partial ring can preferably be separated for the first time for assembly, but this is done, for example, in the assembly workshop and / or by the assembler. That is, in advance, the partial ring can maintain the bond, especially as a set of bonded partial rings, which makes it easy to handle. For example, a partial ring may be stored, transported, processed and / or processed as a set or combined between a first process part and a second process part, ie between production and separation together. Can be done. With respect to transport, this can also include transport within the manufacturing plant, eg, transport from the machine that manufactures the partial rings together to the assembly site. The treatment can include, for example, a coating.

According to another embodiment, it is intended that at least two partial rings manufactured together will be assembled into one stator disk during pump assembly. Thus, at least two partial rings manufactured together and coupled to one member after the first process portion complement each other in the sense that these partial rings together form a stator disk after assembly. As a result, erroneous assembly can be easily avoided. It is easy for the fitter to see which partial rings complement each other. In particular, if the assembler separates, for example, breaks the partial ring for the first time just before assembling, accurate mapping is easily guaranteed. This applies not only to the question of which partial rings complement each other, but also to their relative orientation. That is, for example, it is effectively prevented that one of the partial rings is mistakenly rotated, and as a result, the upper side and the lower side are mistaken for each other. If the assembler breaks the partial ring by hand, the assembler can also assemble the partial ring directly because the assembler has the partial ring in the correct orientation, especially already in the hand. For example, it can be introduced radially in the intermediate space between the two rotor disks. That is, assembly is simplified and additional possible errors are eliminated.

Essentially, more than one joint with a scheduled separation can be provided between the partial rings after the first process portion. In particular, multiple material bridges can be provided between the partial rings. The at least two spaced joints bond the partial ring, on the one hand, for the required time, eg, reliably enough to maintain the bond during transport, and on the other hand, relatively easily separable, especially fractureable. To be able to form.

Basically, the partial rings can be optionally aligned with each other when manufactured together or in a coupled state. For example, the partial rings can be aligned with each other as if they were aligned with each other after assembly, at least substantially before separation. Optionally, for example, material-saving and / or space-saving arrangement can be selected.

In addition, the problem of the present invention is solved by a set of at least two stator disk partial rings according to claim for this purpose. The partial ring is provided for at least one stator disc in the vacuum pump. The partial rings are joined together in one member, and the joints between the partial rings have a locally reduced material thickness, so that the joints form the planned separation points.

An object of the present invention is the method according to claim 8, that is, a method for manufacturing a vacuum pump, wherein the vacuum pump has at least one ring-shaped stator disk, and the stator disk is the same. In a pump rotor, particularly one set to work with at least one rotor disk to generate pumping action, where the stator disk has at least two separate partial rings, the at least two stator disk partial rings are. It is formed by separating this part from one part or after forming it as one part, and the separation is solved by a method characterized by including a machining process. In addition, this method may include the above-mentioned configuration and / or individual features.

The partial rings can be finally separated from each other, for example by a machining process. Particularly preferably, the machining process allows the material of the joint between the partial rings to be locally shrunk so that the joint constitutes the planned separation point and the partial ring is a separate process. The part is separated at the planned separation point, preferably broken. In this case, the machining process constitutes a partial step of separation and is carried out in preparation for a second separate partial step of separation, i.e. the final separation.

In particular, a first process step in which the blade structure is formed and a second process step in which the separation machining process is carried out, especially the small material bridge is left as the scheduled separation point, and the partial ring is finally scheduled. A third process step separate from the first two process steps is performed at the separation point, where separation, eg breakage, is performed. With respect to the context, the first and second process steps are both parts of the first process part and the third process step is the second process part.

From the above, it goes without saying that the separation at the planned separation site generally includes at least the final separation. Thus, the machining process that is part of the separation is used specifically for the preparation of the final separation and / or the formation of the planned separation site, but can also include the final separation.

The machining process that is part of the separation can preferably be sawing, in particular with a circular saw, for example milling and / or grinding with a side milling cutter. Sawing and milling allow for particularly accurate cutting.

According to the present invention, the two stator disc partial rings are formed from one part, for example by machining from solid material or punching from sheet metal, and then separated from this part, or two stator discs. The partial ring is either formed by separating the parts after being formed as one part, for example by casting. Each separation involves a machining process.

According to an advantageous embodiment, the separation machining process is carried out by a cutting tool with a cutting width of up to 1 mm, in particular a saw blade. Particularly preferably, the cutting width is up to 0.6 mm. During separation with a cutting tool, the material is typically removed, resulting in voids between the partial rings. From this, it can be seen that the partial rings can move to each other in the circumferential direction according to the width of the void in the circumferential direction. Therefore, there is some play in the relative orientation and positioning of the rotor with respect to its axis of rotation. It was found that a particularly small play was obtained with a small cutting width of up to 1 mm, and for this play, the vacuum performance was hardly affected within this play range. Therefore, the small cutting width advantageously harmonizes with the high performance requirements of vacuum pumps for which a simple manufacturing process should be manufactured.

In a particularly preferred embodiment, for both partial rings, one pump active structure is formed by the machining process, and the separate machining process is the same mounting condition as the machining process for forming the pump active structure. It is intended to be done within the scope of. This allows for particularly accurate application of separation machining processes for pump active structures. In this case, no new clamps with complex orientations are needed during the machining process. However, for example, a tool change can be provided during the machining process, which can preferably be done automatically, for example, depending on the type of machine used.

More preferably, multiple sets of each at least two stator disk partial rings can be manufactured by clamping together in one mounting condition on one machine, especially with one clamping tool. Preferably, for each partial ring, a pump active structure can be formed by a machining process. In this case, preferably, the partial rings of each set can be separated, each containing a machining process. Again, it is particularly preferred that the machining process for forming the pump active structure and the separation machining process be performed in one and the same mounting state. Multiple sets are preferably clamped together in one clamping device.

Basically, for at least one set of partial rings, it is preferred that the separation machining process be performed after the formation of the pump active structure. In particular, for each of the sets, the partial ring is separated after the formation of the pump active structure, the separation involves a machining process, and both the forming and separating machining processes of the pump active structure are multiple of the partial discs. It can be intended to be done in the same mounting condition for each of the sets of. For a particularly efficient example, first all pump active structures are formed in all sets of partial rings, then in all sets a separation machining process is performed.

Generally preferably, the formation of the pump active structure is carried out by at least one tool, which is different from the separation machining process. The pump active structure can be formed, for example, by sawing and / or milling.

The raid structure of the turbob circular saw blade is such that two circular and coaxially oriented circular saw blades are introduced into the raw material while rotating, especially so that the stator blade remains between the round saw blades. By doing so, it can be formed.

Ziegburn structures can be created from raw materials by end mills.

On the other hand, basically preferably, the separation machining process can be performed by individual circular saw blades. Both the tool for forming the pump active structure and the tool for separation can be operated preferably in one and the same tool holder, especially between the machining processes of forming and separating the pump active structure. In addition, the tool is changed.

Another aspect of the present invention relates to the vacuum pump according to claim 13. The vacuum pump has at least one ring-shaped stator disk, which is set to work with the rotor of the pump, in particular at least one rotor disk, to generate pumping action. , Has at least two separate partial rings. In this case, the partial ring is separated by at least two separate cuts, and at least one of the separate cuts is oriented diagonally with respect to the rotation axis of the pump rotor. Preferably, both separate cuts are oriented diagonally.

The present invention is essentially a method for manufacturing a vacuum pump that is not currently separately claimed, wherein the vacuum pump comprises at least one ring-shaped stator disk, which is the rotor of the pump. In particular, the stator disk is set to work with at least one rotor disk to generate pumping action, the stator disk has at least two separate partial rings, and the two partial rings are provided by at least two separate cuts. It is aimed at being separated and having at least one of the separated cuts introduced diagonally with respect to the rotation axis of the rotor of the pump and / or the central axis of the stator disk.

The diagonal orientation of the separation cut improves the vacuum performance of the pump. The separation cut is not parallel to the axis of rotation as was customary in the past, but is optically sealed, especially in the axial direction. That is, the particles to be transferred cannot easily flow back through the separated cut portion in the axial direction without being disturbed. Rather, the separable cuts, due to their oblique arrangement, have a particularly similar effect to blades that are also obliquely oriented.

In addition, the oblique placement of the separation cuts allows for easy separation of the partial rings, especially in turbomolecular stator disks, without damaging the blades, even if the blades overlap in the circumferential direction.

Preferably, the separation cut is oriented at least 10 °, particularly at least 20 °, at an angle with respect to the rotation axis of the pump rotor.

The stator disc can preferably be formed as a turbomolecular stator disc. According to an advantageous embodiment, the separation cut is at least substantially radial to the inner blade end, radially with respect to at least one stator blade disposed circumferentially adjacent to the separation cut. Oriented parallel to the outer blade edge and / or the radial blade center.

In general, stator blades and / or stator disk partial rings have their pump active structures formed, for example by machining, in particular sawing and / or milled, formed from sheet metal, or , Can be cast or can be cast.

Basically, for turbo molecular stator discs, the number of blades can be even or odd.

More basically, the two partial rings of the stator disc can form, for example, symmetrical halves, or be selectively asymmetrically split.

Especially in relation to the odd number of blades and / or the asymmetric division of the partial ring, it has been found to be particularly good to keep the partial ring connected through the planned separation points until assembly. This is because it easily guarantees that the complementary halves will be assembled together.

Basically, the vacuum pump described herein can preferably be formed as a molecular vacuum pump, particularly a turbo molecular vacuum pump and / or a Ziegburn vacuum pump. More basically, the pumping action may be molecular, particularly turbomolecular or Ziegburn-like pumping action. More basically, the vacuum pump may include, for example, one or more turbo molecular stator disks and / or a Ziegburn stator disk and / or a turbomolecular pump stage and / or a Ziegburn pump stage. More basically, one, more than one or all stator disks can be formed according to the configurations described herein.

A turbo molecular vacuum pump basically comprises a rotor disk that rotates at least during the operation of the pump and a stator disk that is axially located downstream of the rotor disk of the pump or the axis of rotation of the rotor. Basically, a turbo molecular vacuum pump may also include a plurality of, in particular a large number of rotor disks and stator disks, which may be particularly arranged in the form of a plurality of so-called turbo stages. In addition, the turbomolecular vacuum pump can also include another pump stage based on other pump principles such as Holbeck pump stage, Siegburn pump stage and / or side channel pump stage.

It can be formed as a sink pump, eg, a so-called split flow vacuum pump, i.e., it can also include at least one intermediate inlet in addition to the inlet and outlet.

It goes without saying that the method, the set of partial rings and / or the vacuum pump can be advantageously developed by the individual features or embodiments of different embodiments.

Hereinafter, the present invention will be exemplified by an advantageous embodiment associated with the accompanying drawings.

Perspective view of turbo molecular pump Lower view of the turbo molecular pump of FIG. Cross-sectional view of the turbo molecular pump along the cutting line AA shown in FIG. Cross-sectional view of the turbo molecular pump along the cutting line BB shown in FIG. Cross-sectional view of the turbo molecular pump along the cutting line CC shown in FIG. Multiple stator discs for turbo molecular pumps during the manufacturing process Clamping device for accommodating multiple stator discs during the manufacturing process Two separate partial rings of the stator disc Side view of the separated cut portion between the two stator blades Separation cut in the separation plane The first exemplary arrangement of the two partial rings when forming together A second exemplary arrangement of the two partial rings when forming together A third exemplary arrangement of the two partial rings when forming together

The turbo molecular pump 111 shown in FIG. 1 has a pump inlet 115 surrounded by an inlet flange 113, to which, as is well known per se, a recipient (not shown) can be connected. Gas from the recipient is drawn from the recipient through the pump inlet 115 and can be transferred through the pump to the pump outlet 117, to which a preliminary vacuum pump, such as a rotary vane pump, is connected. be able to.

The inlet flange 113 constitutes the upper end of the housing 119 of the vacuum pump 111 when the vacuum pump is oriented according to FIG. The housing 119 has a lower portion 121, and an electronic device housing 123 is arranged next to the lower portion. The electrical and / or electronic components of the vacuum pump 111 are housed in the electronic device housing 123, for example, to operate the electric motor 125 disposed in the vacuum pump (see also FIG. 3). The electronic device housing 123 is provided with a plurality of ports 127 for accessories. In addition, for example, a data interface 129 and a power supply port 131 according to the RS485 standard are arranged in the electronic device housing 123.

There are also turbo molecular pumps that are connected to external drive electronics rather than having such mounted electronics housings.

The housing 119 of the turbo molecular pump 111 is provided with a water injection inlet 133 in the form of a water injection valve, and the vacuum pump 111 can inject water through the water injection inlet. Furthermore, in the region of the lower portion 121, a seal gas port 135, which is also called a scavenging gas port, is arranged, and the scavenging gas is transferred from the gas transferred by the pump through the scavenging gas port to the electric motor 125 (see, for example, FIG. 3). The electric motor 125 can be introduced into the motor space 137-in which the electric motor 125 is housed in the vacuum pump 111-to protect. Furthermore, two coolant ports 139 are arranged in the lower portion 121, one of these coolant ports is provided as an inlet for the coolant, and the other coolant port is provided as an outlet for the coolant. This coolant can be introduced into the vacuum pump for cooling. Other existing turbomolecular vacuum pumps (not shown) are operated solely by air cooling.

Since the lower side 141 of the vacuum pump can be used as a stand surface, the vacuum pump 111 can be operated while standing on the lower side 141. However, the vacuum pump 111 may be fixed to the recipient via the inlet flange 113 and thereby operated in a suspended state to some extent. In addition, the vacuum pump 111 can be configured to operate even when oriented differently than that shown in FIG. It is also possible to realize an embodiment of a vacuum pump in which the lower side 141 can be arranged sideways or oriented so as to face up instead of facing down. In this case, basically any angle is possible.

In particular, other existing turbomolecular vacuum pumps (not shown) larger than the pumps shown here cannot be operated in an upright position.

Further, various bolts 143 are arranged on the lower side 141 illustrated in FIG. 2, and these bolts fix the parts of the vacuum pump, which are not further specified here, to each other. For example, the bearing cover 145 is fixed to the lower side 141.

In addition, a fixing hole 147 is arranged on the lower side 141, and the pump 111 can be fixed to, for example, a mounting surface through these fixing holes. This is not possible, especially for other existing turbomolecular vacuum pumps that are larger than the pumps illustrated here.

FIGS. 2 to 5 show a coolant line 148, through which the coolant introduced and taken out can circulate through the coolant port 139.

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

A rotor 149 is arranged in the housing 119, and the rotor includes a rotor shaft 153 that can rotate about a rotation shaft 151.

The turbo molecular pump 111 has a plurality of radial rotor disks 155 fixed to the rotor shaft 153 and a stator disk 157 disposed between the rotor disks 155 and fixed to the housing 119, effectively in series with the pump. It has multiple turbo molecular pump stages interposed in it. In this case, the rotor disk 155 and the adjacent stator disk 157 each form one turbo molecular pump stage. The stator discs 157 are held by spacer rings 159 at desired axial spacing from each other.

In addition, the vacuum pumps are radially spaced from each other and have Holbeck pump stages effectively interspersed with each other in the pump. There are other existing turbomolecular vacuum pumps (not shown) that do not have a Holbeck pump stage.

The rotor of the Holbeck pump stage has one rotor hub 161 located on the rotor shaft 153 and two cylinder shell shaped Holbeck rotor sleeves 163, 165 fixed to and supported by the rotor hub 161. These Holbeck rotor sleeves are coaxially oriented with respect to the rotation shaft 151 and are nested with each other in the radial direction. Further, two cylinder shell-shaped Holbeck stator sleeves 167 and 169 are provided, and these Holbeck stator sleeves are also coaxially oriented with respect to the rotation shaft 151 and are nested with each other when viewed in the radial direction. Has been done.

The pump active surface of the Holbeck pump stage is composed of shell surfaces, i.e., radial inner and / or outer surfaces, Holbeck rotor sleeves 163,165 and Holbeck stator sleeves 167,169. The radial inner surface of the outer Holbeck stator sleeve 167 faces the radial outer surface of the outer Holbeck rotor sleeve 163 while forming a radial Holbeck gap 171 and, together with this radial outer surface, a turbo molecule. It constitutes a first Holbeck pump stage following the pump. The radial inner surface of the outer Holbeck rotor sleeve 163 faces the radial outer surface of the inner Holbeck stator sleeve 169 while forming a radial Holbeck gap 173, along with this radial outer surface and a second. Consists of the Holbeck pump stage. The radial inner surface of the inner Holbeck stator sleeve 169 faces the radial outer surface of the inner Holbeck rotor sleeve 165 while forming a radial Holbeck gap 175, and together with this radial outer surface a third. Consists of the Holbeck pump stage.

At the lower end of the Holbeck rotor sleeve 163, a radially extending passage can be provided that connects the Holbeck gap 171 located radially outward by its intervention to the central Holbeck gap 173. In addition, a radially extending passage can be provided at the upper end of the inner Holbeck stator sleeve 169 to connect the central Holbeck gap 173 to the radial inwardly located Holbeck gap 175 by its intervention. .. As a result, the Holbeck pump stages nested in each other are interposed in series with each other. Further, a connecting passage 179 to the outlet 117 can be provided at the lower end of the Holbeck rotor sleeve 165 located inward in the radial direction.

The pump-active surfaces of the Holbeck stator sleeves 167 and 169 each include a plurality of Holbeck grooves spirally extending axially about the rotation shaft 151, but the opposite shells of the Holbeck rotor sleeves 163 and 165. The surface is formed smooth and propels the gas for operating the vacuum pump 111 in the Holbeck groove.

In order to rotatably bearing the rotor shaft 153, a rolling bearing 181 is provided in the region of the pump outlet 117 and a permanent magnet bearing 183 is provided in the region of the pump inlet 115.

In the area of rolling bearing 181 the rotor shaft 153 is provided with a conical spray nut 185 having an outer diameter that increases towards rolling bearing 181. The spray nut 185 is in sliding contact with at least one wiper of the working medium accumulator. For other existing turbomolecular vacuum pumps (not shown), spray bolts can be provided in place of the spray nuts. Therefore, the term "spray tip" is also used in this context as different configurations are possible.

The working medium accumulator has a plurality of hygroscopic discs 187 stacked one above the other, and these discs absorb a working medium for the rolling bearing 181 such as a lubricant.

During operation of the vacuum pump 111, the working medium is transmitted from the working medium accumulator to the rotating spray nut 185 via the wiper by capillary action, and due to centrifugal force, the outer diameter of the spray nut 185 along the spray nut 185. Is transferred towards the rolling bearing 181 in the increasing direction, where the working medium satisfies, for example, the lubrication function. The rolling bearing 181 and the working medium accumulator are surrounded by a tub-shaped insert 189 and a bearing cover 145 in a vacuum pump.

The permanent magnet bearing 183 has a bearing half body 191 on the rotor side and a bearing half body 193 on the stator side, and these bearing half bodies consist of a plurality of permanent magnet rings 195 and 197 stacked vertically vertically, respectively. It has one ring stack. The ring magnets 195 and 197 face each other while forming a radial bearing gap 199, the ring magnet 195 on the rotor side is arranged on the outer side in the radial direction, and the ring magnet 197 on the stator side is arranged on the inner side in the radial direction. ing. The magnetic field present in the bearing gap 199 causes a magnetic repulsive force between the ring magnets 195 and 197 that causes the radial bearing of the rotor shaft 153. The ring magnet 195 on the rotor side is supported by a carrier portion 201 of the rotor shaft 153, which surrounds the ring magnet 195 from the outside in the radial direction. The stator-side ring magnet 197 is supported by a stator-side carrier portion 203, which extends through the ring magnet 197 and is suspended by a radial brace 205 of the housing 119. Parallel to the rotation shaft 151, the ring magnet 195 on the rotor side is fixed by a cover element 207 connected to the carrier portion 201. The ring magnet 197 on the stator side is fixed in one direction in parallel with the rotation shaft 151 by a fixing ring 209 coupled to the carrier portion 203 and a fixing ring 211 coupled to the carrier portion 203. In addition, a disc spring 213 can be provided between the fixed ring 211 and the ring magnet 197.

An emergency or safety bearing 215 is provided within the magnetic bearing, which slips without contact during standard operation of the vacuum pump 111, with the rotor 149 relative to the stator being excessive. Only when displaced radially to engage to form a radial stopper for the rotor 149, this is done to prevent collisions between the stator-side and rotor-side structures. .. The safety bearing 215 is formed as an unlubricated rolling bearing and, together with the rotor 149 and / or the stator, constitutes a radial gap that causes the safety bearing 215 to be released during standard pump operation. The radial displacement in which the safety bearing 215 engages is large enough so that the safety bearing 215 does not engage during standard operation of the vacuum pump, while at the same time colliding between the structure on the stator side and the structure on the rotor side. Is set small enough to prevent under all circumstances.

The vacuum pump 111 has an electric motor 125 for rotationally driving the rotor 149. The anchor of the electric motor 125 is composed of a rotor 149, and the rotor shaft 153 of the rotor extends through the motor stator 217. A permanent magnet device can be arranged in a portion of the rotor shaft 153 extending through the motor stator 217, either radially outward or embedded. An intermediate space 219 is arranged between the motor stator 217 and the portion of the rotor 149 extending through the motor stator 217, the intermediate space having a radial motor gap through which the motor The stator 217 and the permanent magnet device can be magnetically affected to transmit the drive torque.

The motor stator 217 is fixed in the housing in the motor space 137 provided for the electric motor 125. Through the seal gas port 135, a seal gas, also called scavenging gas, which can be, for example, air or nitrogen, can reach into the motor space 137. Through the seal gas, the electric motor 125 can be protected from the process gas, for example, the corrosive action component of the process gas. The motor space 137 can also be evacuated through the pump outlet 117, i.e., the inside of the motor space 137 is at least largely dominated by the vacuum pressure generated by the preliminary vacuum pump connected to the pump outlet 117.

In addition, it is well known between the rotor hub 161 and the wall 221 that defines the motor space 137, in particular to achieve good sealing of the motor space 217 for the Holbeck pump stage located radially outward. The so-called labyrinth seal 223 can be provided.

The assembly of the stator disk 157 can be described, for example, with reference to FIG. There, a plurality of stator disks 157 are arranged in an intermediate space between the rotor disks 155, respectively. For assembly, first, a rotor 149 with all its rotor disks 155 is assembled. Each stator disk 157 consists of two partial rings, each occupying about 180 ° around it. The two complementary partial rings are introduced radially into the intermediate space between the two rotor disks 155 and assembled into the rotor disk 157. A spacer ring 159 is placed between the two stator discs 157, which keeps the stator discs 157 in position with respect to each other and with respect to the housing 119.

FIG. 6 illustrates an exemplary manufacturing process for a turbomolecular pump in which a plurality of stator discs 10, i.e., turbomolecular stator discs, are both manufactured in one mounted state. For this purpose, the ring discs are clamped together in the clamping device 12 as a semi-finished product for the stator disc 10 and machined on one and the same machine.

The clamping device 12 is configured as a kind of tower, and the segments 14 of the clamping device 12 and the stator disk 10 are alternately inserted so as to overlap each other in order to clamp the stator disk 10 or its semi-finished products, and then the outermost in the axial direction. The segments 14 of the above are fixed to each other, for example, by bolts (not shown here). In this case, the stator disc 10 is clamped in the axial direction so that it is immovably arranged.

In FIG. 6, the clamp device 12 is shown partially disassembled to illustrate its configuration and assembly. In addition, the tool in use, ie the circular saw blade, is illustrated. This is also used for illustration purposes only. It goes without saying that the tool is typically only activated after the clamping device 12 is configured in the finished state and the stator disc 10 or its semi-finished product is steadily clamped.

The stator disc 10 is already fully manufactured in the figure of FIG. 6, but has not yet been finally separated into partial rings as intended for the assembly of the stator disc 10.

The stator disc 10 is similarly configured and is illustrated in detail by the above stator disc 10. The stator disc 10 has an inner ring 18 that supports a large number of stator blades 20 evenly distributed over the perimeter. In this case, each stator blade 20 extends radially outward from the inner ring 18 and is oriented obliquely with respect to the shaft 22. The shaft 22 constitutes the central shaft of the stator disc 10 and the clamping device 12. The central shaft 22 of the stator disc 10, in the assembled state, coincides with the rotating shaft of the rotor of the pump, for example, the rotating shaft 151 in FIG.

For the formation of the stator discs up to the state shown in FIG. 6, especially the blade structure thereof, as illustrated in FIG. 7, first, the ring disc 24 is used as a semi-finished product for each stator disc 10 and the clamp device 12 is used. Including being clamped in. The blades 20 are then sequentially machined from the solid material of the ring disc 24. For this purpose, for example, two circular saw blades (not shown) arranged parallel and coaxially but spaced apart can rotate and enter the material of the ring disc in the radial direction. The stator blade 20 remains between the circular saw blades. After the circular saw blade is ejected again, the clamping device 12, i.e., is rotated by the intended angular spacing of the stator blades 20, and the next stator blades 20 are formed as well. In this case, the circular saw blade is diagonally arranged as in the circular saw blade 16 of FIG. 6-where the circular saw blade 16 is used to separate the stator disc 10 into partial rings. .. Two parallel circular saw blades for forming the stator blades can be operated, for example, with the same tool holder 26, with the formation of the stator blades 20 and the machining process to separate the stator discs 10 into partial rings. During that time, the tool is changed.

Preferably, further, both the formation of the stator blade 20 and the separation and cutting by the circular saw blade 16 can be performed in one mounting state. This is because, for the arrangement of FIG. 6, three ring disks 24 are first clamped in the clamping device 12 as semi-finished products, and then the blade structure and the stator of the stator disk 10 without releasing the clamping device 12 in the middle. It means that both machining processes with the circular saw blade 16 for separating the discs are carried out. The clamping device 12 can then be released and the completed stator disc can be removed as a partial ring or as a set of partial rings. This has the advantage that the separation cut introduced by the circular saw blade 16 can be accurately oriented with respect to the stator blade 20 and therefore does not require alignment within the range of the new clamp.

That is, the separation of the stator disc 10 into the partial ring involves machining with a circular saw 16. The cutting process by the circular saw blade 16 is preferably performed after at least the entire blade structure of the stator disc 10, especially all the stator discs 10, has been formed in a completed state.

The circular saw blade 16 is oriented here at an angle with respect to the shaft 22 and substantially parallel to the stator blade 20, and the circular saw blade is inserted between the stator blades. That is, an oblique separation cut with respect to the shaft 22 is introduced into the inner ring 18. Each stator disc 10 is introduced with two separate cuts that face each other with respect to the axis 22, i.e., offset by 180 ° in the circumferential direction. As a result, the stator disc 10 is divided into two partial rings that are symmetrical with respect to the axis 22.

The clamping device 12 comprises a plurality of notches 28, each of which allows the circular saw blade 16 to enter the inner ring 18 without removing the material of the clamping device 12 or colliding with the clamping device. It is provided in. Such a notch 28 is preferably present for all intended separation cuts, i.e., as opposed to the notch 28 on the opposite side of the gaze person in FIG. There are three notches.

The notch 28 comprises a predetermined angular position, i.e., the same angular position. To ensure this angular position during clamping, the segment 14 can be oriented at the correct angle, for example with a long alignment pin. Due to such alignment pins, a notch 30 is seen in the upper segment 14.

The completed stator disc 10 finally separated into two partial rings 31 is shown in FIG. This stator disc has two diagonally separated cuts 32. The partial rings 31 are shown here with large interstitial spacing for illustration purposes, and this spacing does not match that of the assembled state, and does not match that of the clamped state within the clamping device 12. That is, the separation and cutting section 32 is shown too broadly for illustration purposes. That is, the separated cutting portion 32 is not shown here with a width introduced by the circular saw blade 16 or provided in a state where the separated cutting portion is assembled. Actually, the cutting width of the separation cutting portion 32 or the circular saw blade 16 is preferably less than 1 mm.

The diagonal arrangement of the separate cuts 32 is illustrated in more detail in FIG. The separation cut portion 32 is oriented there diagonally with respect to the axis 22, i.e. with an angle 34 with respect to the axis 22. As already shown, the shaft 22 coincides with the rotating shaft of the rotor as assembled in the vacuum pump.

The separate cutting portion 32 is further oriented parallel to both adjacent stator blades 20. Therefore, the angle 34 coincides with the so-called angle of attack of the stator blade 20, that is, the angle with respect to the axis 22 of the stator blade.

The stator blades 20 are arranged so as to overlap each other, that is, a part of each stator blade 20 projects into a region of adjacent stator blades 20 in the axial direction. This can be seen in FIG. 9 from the fact that the line of the shaft 22 intersects both stator blades 20 in the figure. The overlapping arrangement of the stator blades 20 also causes the gaze person to be unable to see through between the stator blades 20 in the gaze direction along the axis 22. In this connection, we will also talk about the close optical arrangement. This allows for particularly good vacuum performance. This is because the particles to be transferred cannot easily move axially through the stator disc 10 in the opposite direction to the pump direction.

As is particularly well recognized in FIG. 9, the oblique arrangement of the separation cuts 32 allows the inner ring 18 to be separated without damaging the stator blades 20 despite the overlapping arrangement of the stator blades 20. .. On the other hand, the axial separation cutting will damage the stator disk 20 at least at the inner end in the radial direction.

Further, the separation cutting portion 32 itself is optically close in the axial direction, unlike the separation cutting oriented in the axial direction. That is, the separation / cutting portion 32 prevents the molecule to be transferred from easily moving through the separation / cutting portion in the axial direction opposite to the pump direction. Therefore, the vacuum performance is improved as compared with the axial separation cutting.

In FIG. 10, the separation cut portion 32 is illustrated in its cross section, i.e., the cross section of the inner ring 18 can be seen. Two more small material bridges 36 can be seen in this cross section. These are left unattended, for example, during the process according to FIG. 6 by allowing the circular saw blade 16 to penetrate deeper into the inner ring 18 so that the material bridge 36 remains, rather than finally separating the inner ring. Can be left.

The material bridge 36 constitutes a joint of one member between the two partial rings 31 of the stator disc 10. Thereby, the partial ring 31 is maintained as a set of partial rings 31 and is stored, transported and possibly another process and / or processed as a set of partial rings 31 following the machining process illustrated in FIG. Can be done.

In this case, the material bridge 36 is dimensioned so that, on the one hand, the partial ring is reliably maintained so that it can be stored, transported or processed and / or processed, and on the other hand, it can be easily broken by hand when needed. It is set. That is, the material bridge 36 constitutes the planned fracture point 38. This allows the fitter to separate the partial ring 31 for the first time for assembly, i.e., to easily break at the planned break point 38. The handling of the partial ring 31 as a set in advance is particularly easy. In addition, it is always clear to the fitter which partial rings 31 complement each other. This is because the partial ring is provided as a set combined with the fitter. Therefore, the causes of possible errors during assembly are reduced.

Since the material bridge 36 has a reduced material thickness with respect to the inner ring 18, the material bridge constitutes a planned separation point or a planned break point 38. In this case, the material thickness is significantly reduced so that the material bridge 36 can be separated without invading the inner ring 18, for example bending. Therefore, the exact shape of the inner ring 18 and the placement and orientation of the stator blades 20 remain maintained, yet the partial ring 31 can be easily separated by hand.

It goes without saying that the material bridge 36 can be formed differently depending on the strength requirements. For example, only the material bridge 36 may be provided in the separation cutting portion 32. The shape and number of such material bridges can be easily influenced by the guide trajectory of the circular saw blade 16 in the context of the process according to FIG. Typically, the stator disc comprises two separate cuts 32, as is the case in FIG. 8, for example. In this case, basically, one or a plurality of material bridges may be provided on at least one of the separated cutting portions 32, but for example, at least one material bridge may be provided on each of the separated cutting portions 32.

The stator discs 10 shown in FIGS. 6-9 are manufactured by machining and their separation into partial discs also involves a machining process, ie sawing with a circular saw blade 16. The selective manufacturing method for the stator disk or blade structure is, in particular, manufacturing from sheet metal-the blade structure is typically formed by punching and bending from the original sheet metal-and by casting. In both cases, the stator disc can then be separated by a machining process, for example by a circular saw.

The following description with respect to FIGS. 11 to 13 particularly relates to manufacturing from sheet metal, and the description is basically applicable to manufacturing by machining and manufacturing by casting.

11-13 show a set of two partial rings 31, respectively, of the stator disc, the partial rings 31 being arranged differently from each other. The partial rings 31 are connected via a planned separation point 38, particularly a planned break point. The joint or planned separation point 38 is formed as a small material bridge and does not appear to be so in FIGS. 11-13. The joints have a material thickness that is clearly reduced relative to the portion of the partial ring 31 to which they-the inner ring 18 and / or the outer ring 40 of the partial ring 31 in FIGS. 11-13 are attached. Be prepared.

FIG. 11 shows a particularly simple variation in which the partial rings 31 are arranged facing each other in the same manner that they are arranged facing each other even in the assembled state. FIGS. 12 and 13 show selective placement variations used specifically for optimal material utilization of sheet metal-partial rings 31 are punched out of this sheet metal. Depending on the specific dimensional setting of the stator disc, for example, the arrangement according to FIG. 12 or the arrangement shown in FIG. 13 may be advantageous.

The joint or planned separation point 38 is always attached to the inner ring 18 and / or the outer ring 40 of the partial ring 31 in FIGS. 11-13, but not particularly to the blade. In FIG. 11, the two scheduled separation points 38 connect the outer ring 40 of one partial ring 31 to the outer ring 40 of the other partial ring 31, and the two scheduled separation points 38 are inside the one partial ring 31. The ring 18 is coupled to the inner ring 18 of the other partial ring 31. In FIG. 12, both planned separation points 38 connect the inner ring 18 of one partial ring 31 to the outer ring 40 of the other partial ring 31. In FIG. 13, two scheduled separation points 38 connect the inner ring 18 to the outer ring 40, and two other scheduled separation points 38 connect the inner ring to the inner ring 18.

By the method illustrated in the figure, the partial ring 31 is a first process portion in which the partial ring 31 comprises at least a blade structure after the first process portion and is coupled into one member between the partial rings 31. The joints of the are provided with a locally reduced material thickness, so that the joints are manufactured together to form the planned separation point 38.

With respect to FIGS. 6-10, the first process portion is the formation of a blade structure with a parallel rotating saw blade and subsequent partial steps of separation, ie a circular saw into the inner ring 18 so that the material bridge 36 remains. Includes the entry of blade 16. The second partial step of separation, the final separation by manual break, constitutes a second process part separate from the first process part. That is, in this other second process part, it is finally separated at the planned separation point. Therefore, the separation involves two partial steps-the first of which is a machining process, ie composed by sawing and is part of the first process part. The second partial step comprises the actual final separation of the separation rings from each other at the planned separation points and constitutes the second process part.

With respect to FIGS. 11-13, the first process portion comprises forming a blade structure by punching and bending from sheet metal as a starting material. Again, a small material bridge is left at the planned separation point 38, which is particularly based on the appropriate formation of the punching tool used. In a second process part separate from the first process part, the partial ring is separated at the planned break point, but for this purpose it is easily broken, for example, by the assembler just before assembly.

It can be seen that the second process part is completely independent of the first process part and can eventually be done at any time point. Preferably, the partial rings 31 are separated from each other for the first time for assembly. Along the way, the partial ring 31 can be stored and transported as a set of two optionally coupled partial rings 31, for example further processed and / or processed. This allows for particularly easy handling in the manufacturing process of turbo molecular vacuum pumps.

Although a set of two partial rings is illustrated in FIGS. 6 to 13, it is also conceivable to provide more than two partial rings as a set or to combine them via a planned separation point. Thus, it is also possible to provide at least two stator disk partial rings, especially four partial rings, as a set, for example for turbo molecular pumps. For example, within the set, all stator discs of the pump or partial rings of all similar stator discs can be provided.

The embodiment described in connection with the figure relates to a turbo molecular stator disk by way of example. In that respect, the description for FIGS. 11-13 also applies to, for example, the Ziegburn stator disc.

111 Turbo Molecular Pump 113 Inlet Flange 115 Pump Inlet 117 Pump Outlet 119 Housing 121 Bottom 123 Electronic Equipment Housing 125 Electric Motor 127 Accessory Port 129 Data Interface 131 Power Supply Port 133 Water Injection Inlet 135 Sealed Gas Port 137 Motor Space 139 Coolant Port 141 Below Side 143 Bolt 145 Bearing cover 147 Fixing hole 148 Coolant line 149 Rotor 151 Rotating shaft 153 Rotor shaft 155 Rotor disk 157 Stator disk 159 Spacer ring 161 Rotor hub 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 passage 181 Rolling bearing 183 Permanent magnet bearing 185 Spray nut 187 Disc 189 Insert 191 Rotor side bearing half body 193 Stator side bearing half body 195 Ring magnet 197 Ring Magnet 199 Bearing gap 201 Carrier part 203 Carrier part 205 Radial brace 207 Cover element 209 Support ring 211 Fixed ring 213 Countersunk spring 215 Emergency or safety bearing 217 Motor stator 219 Intermediate space 221 Wall 223 Labyrinth seal 10 Stator disk 12 Clamping device 14 Segment 16 Round saw blade 18 Inner ring 20 Stator blade 22 Ring disk 26 Tool holder 28 Notch 30 Notch 31 Partial ring 32 Separation cut 34 Angle 36 Material bridge 38 Scheduled separation / planned break 40 Outer ring

Claims (13)

A method for manufacturing a vacuum pump (111), wherein the vacuum pump has at least one ring-shaped stator disk (10,157), which is the stator disk of the pump (111) rotor (149). Or set to work with at least one rotor disk ( 155 ) to generate pumping action, where the stator disk (10,157) has at least two separate partial rings (31).
In the first process portion, at least two stator disk partial rings (31) are as follows, i.e., the partial ring (31) comprises at least one pump active structure after the first process portion. Together so that the joints between the partial rings (31) that are coupled to one member form a planned separation point (36,38) that has a locally reduced material thickness and is manually breakable. Manufactured and the partial ring (31) is characterized by being separated at the planned separation point (38) by manual fracture in a second process portion separate from the first process portion. Method. The method according to claim 1, wherein the partial ring (31) is manufactured in a completely completed state except for the joint portion thereof before being separated. The method according to claim 1 or 2 , wherein the planned separation point (38) includes at least a planned break point, a material bridge (36) and / or a notch. The partial ring (31) is separated for the first time for assembly and / or the partial ring (31) is stored and transported in a coupled state between the first process part and the second process part. The method according to any one of claims 1 to 3 , wherein the process is processed and / or processed. According to any one of claims 1 to 4 , at least two partial rings (31) manufactured together are assembled into one stator disk (10,157) at the time of assembling the pump (111). The method described. In a set of at least two stator disc partial rings (31) for at least one stator disc (10,157) in a vacuum pump (111).
The partial rings (31) are joined together in one member, and the joints between the partial rings (31) have a locally reduced material thickness and are manually breakable. A set characterized by constituting a location (38). At least two stator disk partial rings (31) are formed by separating this part from one part (24) or after forming it as one part, the separation comprising a machining process. The method according to any one of claims 1 to 5 . The method of claim 7 , wherein the machining process is sawing , milling and / or grinding. The method according to claim 7 or 8 , wherein the machining process is performed by a cutting tool (16) or a saw blade having a cutting width of up to 1 mm or up to 0.6 mm. For both partial rings (31), one pump active structure is formed by the machining process, and the separated machining process is the same mounting condition as the machining process for forming the pump active structure. The method according to any one of claims 7 to 9 , wherein the method is performed within the range of. Multiple sets of each at least two stator disk partial rings (31) are manufactured in one mounting condition on one machine, for each partial ring (31) the pump active structure is a machining process. The method of any one of claims 7-10 , wherein each set of partial rings (31) is separated and the separation comprises a machining process, respectively. It has at least one ring-shaped stator disk (10,157), and this stator disk cooperates with the rotor (149) of the pump (111) or at least one rotor disk (155) to generate a pumping action. In a vacuum pump (111) where the stator disk (111) is set for and has at least two separate partial rings (31).
The stator disk (10,157) has at least two separate cuts (32), and at least one of the separate cuts (32) is the rotating shaft (22) of the rotor (149) of the pump (111). , 151) diagonally oriented , configured by a joint between the partial rings (31) that are present in the separate cut (32) and that join the partial ring (31) to one member. Partial rings (31) separated by hand breaks are assembled to the stator discs (10,157) at planned separation points (38) with locally reduced material thickness and breakability by hand. A vacuum pump (111) characterized by being . The stator disk (10,157) is a turbomolecular stator disk, and the separation cutting portion (32) is at least substantially substantially adjacent to the separation cutting portion (32) in the circumferential direction (20). The vacuum pump (111) according to claim 12 , wherein the vacuum pump (111) is oriented in parallel with respect to the relative direction.

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