EP2894348A1 - Stator disc - Google Patents

Abstract

The invention relates to a stator disk for a turbomolecular pump, wherein the stator disc extends partially annularly in a plane, has an inner radius and an outer radius and comprises a securing device, by means of which the stator disc at least against radial displacement in the plane relative to an adjacent arranged spacer ring securable is.

Description

The invention relates to a stator disk for a turbomolecular pump, wherein the stator disk extends part-ring-shaped in a plane and has an inner radius and an outer radius.

Turbomolecular pumps serve to generate a vacuum, for example for electron microscopes or mass spectrometers. In this case, gas particles are accelerated by rotor disks of the turbomolecular pump and guided by stator disks in a preferred direction, whereby a vacuum generating flow is formed. To this end, both the rotor disks and the stator disks comprise inclined planes to the plane, which accelerate or deflect the gas particles.

The rotor disks are non-rotatably connected to a high-speed shaft whose axis of rotation defines an axial direction of the turbomolecular pump, while the stator disks are not coupled to the shaft but fixed to a housing of the turbomolecular pump. The rotor and stator discs are alternately arranged in the axial direction and spaced apart by spacers.

During assembly of the turbomolecular pump, the rotor and stator disks and the spacer rings are arranged on the shaft and the resulting package is introduced into the housing of the turbomolecular pump. In this case, it is desirable that, in particular, the stator disks do not move laterally out of the package and, when inserted into the housing, wedging with the same is prevented.

The invention has for its object to provide a stator for a turbomolecular pump, which prevents wedging during assembly of a turbomolecular pump in a simple manner.

The object is achieved by a stator with the features of claim 1 and in particular by the fact that the stator comprises a securing device by means of which the stator is at least secured against radial displacement in the plane relative to an adjacent spacer ring.

The securing device allows the stator disk to be secured against any radial movement in the plane when the turbomolecular pump is being assembled, so that it can not slip out of the rotor disk, stator disk and spacer ring package and become wedged with the turbomolecular pump housing during insertion. As a result, the introduction of the disk package into the housing of the turbomolecular pump and thus ultimately the assembly of the turbomolecular pump as a whole are considerably simplified.

Before the disk package is introduced into the housing of the turbomolecular pump, rotor disks, stator disks and spacer rings are successively stacked on one another in the axial direction, for example, so that the rotor and stator disks alternate with spacers between them. If the stator disks and spacer rings abut each other, the stator disks are secured by means of the securing device to the spacer rings against radial displacement in the plane. An axial movement and a rotation of the stator disks about the axial direction, however, can remain possible.

Advantageous embodiments of the invention are described in the subclaims, the description and the drawings.

According to a preferred embodiment, the securing device comprises at least two, in particular three, protruding from the plane projections. The projections may be formed, for example, as protruding noses or folds, which protrude in particular perpendicularly, that is in the axial direction of the stator disc. If the projections engage in complementary recesses of an adjacent spacer ring, the stator disk is effectively secured against rotation and displacement in the plane.

Also can be formed by one or more of the projections a stop surface, which comes to lie on a shoulder of an adjacent spacer ring. In particular, the stop surface extends in the circumferential direction and thus prevents the stator disk from coming out of the stack of stator, rotor and spacer disks. It is additionally advantageous that a radial centering of the stator can be achieved by the concerns of the stop surface on the shoulder.

Alternatively, the projections can also engage in grooves formed as grooves of an adjacent spacer ring. As a result, in principle, a displacement of the projections along the grooves is possible. To secure the stator disk against in-plane displacement as well, the projections may engage in at least two grooves whose directions of extension enclose an angle with each other, i. E. not parallel to each other.

Preferably, at least three projections are provided, of which two engage in parallel grooves and a third projection can engage in a groove which forms an angle with the other grooves. By using more than two projections higher forces can be absorbed and the stator can be better secured against radial displacement in the plane.

According to a further advantageous embodiment, at least two projections with the center of curvature of the stator at an angle of not equal to 180 °. Such an arrangement of the projections prevents in particular in grooves extending in the circumferential direction, a displacement of the stator in the radial direction. The protection against radial displacement takes place all the more reliable, the further the angle formed by two projections with the center approaches 90 °.

Advantageously, the angle is 75 ° to 105 ° and preferably 90 °. In the case of a semicircular stator disk, for example, two projections may be arranged in the region of the ends of the stator disk, and at least one further projection may be arranged in the circumferential direction centrally between the ends of the stator disk. This means that the further projection encloses an angle of approximately 90 ° with the center of curvature and the projections arranged at the ends. In addition, one or more further projections may be provided.

In particular, the projections at the ends of the stator disc also serve to prevent a superposition of two adjacent semicircular stator discs.

Instead of a plurality of noses or folds, the projections may also be formed by a single protruding nose or fold and by blades of the stator disc, which are inclined to the plane defined by the stator disc and thus protrude out of the plane. The nose or fold can engage in a groove of an adjacent spacer ring and secure the stator so against radial movement in the direction of the nose or fold to the shaft of the turbomolecular pump. At the same time, the blades on an outer wall engage the groove to secure the stator disc against any radial movement away from the shaft of the turbomolecular pump.

According to a further advantageous embodiment, the stator is integrally formed. The stator disc may e.g. be formed as a stamped bent part of a metal sheet. Alternatively, the stator can also be worked out of a solid material, for example by milling.

Particularly preferably, the securing device is formed by bent material of the stator. For this purpose, in a stamping bending process, for example, an edge portion of the stator can be bent to form the securing device. For the safety device no additional material must be attached to the stator in this way.

According to a further advantageous embodiment, an in-plane recess of the stator is formed by the bent material. In stator disks, the blades are usually limited at least in some areas by recesses. If the material to be punched out anyway for the recess is instead bent over and used as a securing device, it is possible to dispense with the provision of additional recesses or the use of additional material for the securing device. In addition, the securing device can be formed in the same process step of the stamping bending process, such as, for example, the blades of the stator disk.

According to a further advantageous embodiment, a portion of at least one of the projections extends at least partially parallel spaced from the plane. The projection may thus have, for example, an L or S shape, whereby the projection has an enlarged contact surface in a groove of the spacer ring. As a result, the stator is even better protected against radial displacement in the plane.

Preferably, the securing device is designed like a bayonet. This means that, for example, an L-shaped or S-shaped projection can engage behind an undercut of the spacer ring. When mounting the rotor and stator, the stator can thus be secured in the axial direction of the spacer.

Alternatively, the securing device may comprise a circumferential elevation. Instead of a plurality of protruding individually from the plane projections, the securing device may be formed continuously in the circumferential direction, for example by a circumferential collar.

Alternatively or additionally, the securing device comprises at least two recesses in the stator disk. In these recesses, for example, projections of the spacers can engage and prevent in this way a radial displacement of the stator relative to the spacer ring. For example, the projections of the spacers can engage in already existing recesses which define the blades.

According to yet another advantageous embodiment, the securing device is arranged in the region of an outer edge of the stator disk. In this way, it is ensured that the securing device can engage in the spacers, which in turn are located in the region of the outer edge of the stator disk, when the rotor and stator packs are stacked.

The securing device may be formed plastically deformable and be brought by bending in a predetermined position. In this way, tolerances, for example a spacer ring, which occur in the production process can be compensated by bending the securing device. According to a further advantageous embodiment, the securing device comprises a knurling and / or a toothing in the region of an outer edge of the stator disk. For example, a toothing of the stator disk can engage in a knurling of a spacer. It can be provided in the circumferential direction one, two or more areas with a toothing, which in particular form an angle of 90 ° with each other. In this way, both a rotation and a radial displacement of the stator in the plane is prevented. Alternatively or additionally, the stator disc may also have a knurling in which a toothing of a spacer ring engages.

The invention further comprises a method for producing a turbomolecular pump provided for a stator which extends part-ring in a plane having an inner radius and an outer radius and comprises a securing means by which the stator disc at least against radial displacement in the plane relative to a adjacent arranged spacer ring is securable. The method according to the invention is characterized in that the securing device and at least one blade of the stator disk are formed by punching or laser cutting and subsequent bending. Thus, the safety device and the blade can be formed in one and the same process and thus particularly economically.

Furthermore, the invention also relates to a turbomolecular pump having at least one stator disk of the type described above and a spacer ring, wherein the securing device cooperates with the spacer ring to secure the stator disk against movement in the plane. The aforementioned advantages and further developments of the stator disk apply correspondingly to the turbomolecular pump according to the invention.

According to an advantageous embodiment of the turbomolecular pump, the stator disc comprises a securing device, which cooperates with at least one recess of the spacer ring. For example, the at least one recess may be formed by a groove extending in the circumferential direction of the spacer ring or by at least one depression of the spacer ring.

Fig. 1

eine erfindungsgemäße Turbomolekularpumpe in Querschnittsansicht;

Fig. 2

eine erste Ausführungsform einer erfindungsgemäßen Statorscheibe in bereichsweiser (a) Seitenansicht und (b) Ansicht von oben;

Fig. 3

eine zweite Ausführungsform einer erfindungsgemäßen Statorscheibe in bereichsweiser (a) Seitenansicht und (b) Ansicht von oben;

Fig. 4

eine dritte Ausführungsform einer erfindungsgemäßen Statorscheibe in bereichsweiser (a) Seitenansicht und (b) Ansicht von oben;

Fig. 5

eine vierte Ausführungsform einer erfindungsgemäßen Statorscheibe in (a) einer Ansicht von oben, (b) einer Ansicht eines Schnitts in Umfangsrichtung und (c) einer Ansicht eines Schnitts in radialer Richtung;

Fig. 6

das Zusammenwirken einer Statorscheibe mit einem Distanzring in schematischer Schnittansicht;

Fig. 7

eine fünfte Ausführungsform einer erfindungsgemäßen Statorscheibe in (a) Ansicht von oben, (b) seitlicher Schnittansicht, (c) seitlicher Detailansicht und (d) Detailansicht von oben; und

Fig. 8

eine sechste Ausführungsform einer erfindungsgemäßen Statorscheibe in (a) Ansicht von oben und (b) das Zusammenwirken mit einem Distanzring in bereichsweiser Seitenansicht.

Hereinafter, the invention will be described by means of possible embodiments with reference to the accompanying drawings. Show it:

Fig. 1

a turbomolecular pump according to the invention in cross-sectional view;

Fig. 2

a first embodiment of a stator according to the invention in a section (a) side view and (b) top view;

Fig. 3

a second embodiment of a stator according to the invention in a section (a) side view and (b) top view;

Fig. 4

a third embodiment of a stator according to the invention in a section (a) side view and (b) top view;

Fig. 5

a fourth embodiment of a stator according to the invention in (a) a view from above, (b) a view of a section in the circumferential direction and (c) a view of a section in the radial direction;

Fig. 6

the interaction of a stator with a spacer ring in a schematic sectional view;

Fig. 7

a fifth embodiment of a stator according to the invention in (a) top view, (b) side sectional view, (c) side detail view and (d) detail view from above; and

Fig. 8

a sixth embodiment of a stator according to the invention in (a) view from above and (b) the interaction with a spacer ring in partial side view.

In the Fig. 1 shown turbomolecular pump 10 comprises a pump inlet 14 surrounded by an inlet flange 12 and a plurality of pumping stages for conveying the gas present at the pump inlet 14 to a in Fig. 1 not shown pump outlet. In a housing 16 of the turbomolecular pump 10, a rotor 18 is arranged with a about a rotational axis 20 rotatably mounted rotor shaft 22.

To generate a pumping action, the turbomolecular pump 10 comprises a plurality of pump-effectively connected in series turbomolecular pumping stages with a plurality of attached to the rotor shaft 22 rotor disks 24 and in the axial direction between the rotor disks 24 stator 26th The stator 26 are by spacer rings 28 at a desired axial distance from one another held.

Furthermore, three Holweckpumpstufen arranged one inside the other in the radial direction and pump-connected in series with one another are provided. The rotor-side part of Holweckpumpstufen includes one connected to the rotor shaft 22 Rotor hub 30 and two fixed to the rotor hub 30 and carried by this cylinder jacket Holweckrotorhülsen 32, 34, which are coaxial with the axis of rotation 22 oriented and nested in the radial direction. Furthermore, two cylinder jacket-shaped Holweckstatorhülsen 36, 38 are provided, which are also coaxial with the axis of rotation 22 oriented and nested in the radial direction.

The pump-active surfaces of the Holweckpumpstufen are each formed by each other with the formation of a narrow radial Holweckspalts radial lateral surfaces of a Holweckrotorhülse 32, 34 and a Holweckstatorhülse 36, 38. In each case, one of the pump-active surfaces is smooth - mainly that of Holweckrotorhülse 32, 34 - and the opposite pumping surface of the Holweckstatorhülse 36, 38 has a structuring with helically around the rotation axis 22 around in the axial direction extending grooves in which during rotation of the rotor 18, the gas is propelled and thereby pumped.

The rotatable mounting of the rotor shaft 22 is effected by a roller bearing 40 in the region of the pump outlet and a permanent magnet bearing 42 in the region of the pump inlet 14.

The permanent magnet bearing 42 comprises a rotor-side bearing half 44 and a stator bearing half 46, each comprising a ring stack of a plurality of stacked in the axial direction of permanent magnetic rings 48, 50, wherein the magnetic rings 48, 50 opposite to form a radial bearing gap 52.

Within the magnetic bearing 42 an emergency or fishing camp 54 is provided, which is designed as an unlubricated roller bearing and idles in normal operation of the turbomolecular pump 10 without contact and only at an excessive radial displacement of the rotor 18 with respect to the stator is engaged to form a radial stop for the rotor 18, which prevents a collision of the rotor-side structures with the stator-side structures. The emergency bearing 54 thus defines the maximum radial deflection of the rotor 18th

In the region of the roller bearing 40, a conical injection nut 56 with an outer diameter increasing towards the rolling bearing 40 is provided on the rotor shaft 22. The spray nut 56 is in sliding contact with at least one wiper of a plurality of stacked absorbent disks 58 having an operating means such as e.g. a lubricant for the rolling bearing 40 are soaked.

In operation of the turbomolecular pump 10, the resource is transmitted by capillary action of the resource storage on the wiper on the rotating spray nut 56 and due to the centrifugal force along the spray nut in the direction of increasing outer diameter of the spray nut 56 to the rolling bearing 40 promoted towards where it for example fulfills a lubricating function.

Turbomolecular pump 10 includes an engine compartment 60 into which rotor shaft 22 extends. The engine compartment 60 is sealed in the region of the entry of the rotor shaft 22 by a victory track 62 with respect to a working or suction chamber of the turbomolecular pump 10. A barrier gas inlet 64 allows delivery of a barrier gas into the engine compartment 60.

In the engine compartment 60, a drive motor 66 is arranged, which serves for the rotational driving of the rotor 18. The drive motor 66 comprises a motor stator 68 with a core 70 and with several in Fig. 1 only schematically illustrated coils 72 which are defined in provided on the radially inner side of the core 70 grooves of the core 70. The core 70 consists of a laminated core with several in the axial direction stacked sheet metal discs made of a soft magnetic material.

The rotor of the drive motor 77, which is also referred to as an armature, is formed by the rotor shaft 22, which extends through the motor stator 68 therethrough. On the extending through the motor stator 68 through portion of the rotor shaft 22, a permanent magnet assembly 74 is fixed radially on the outside. Between the motor stator 68 and the section of the rotor shaft 22 extending through the motor stator 68, a radial motor gap 76 is formed, via which the motor stator 68 and the permanent magnet arrangement 74 influence magnetically for transmission of the drive torque.

The permanent magnet assembly 74 is fixed to the rotor shaft 22 by means of gluing and / or shrinking and / or pressing. The permanent magnet arrangement 74 comprises a soft-magnetic yoke 75a made of iron sheets or solid iron and a permanent magnet 75b. An encapsulation 80, which is designed as a CFK or stainless steel sleeve, surrounds the permanent magnet arrangement 74 on its radial outer side and seals it against the motor gap 76. On the rotor shaft 22, a balancing ring 78 is further attached by gluing and / or shrinking and / or pressing, which has threaded holes for receiving balancing weights. The balancing ring 78 has no direct mechanical connection to the permanent magnet assembly 74 in order to transmit any axial constraining forces on the permanent magnet assembly 74.

A control and power supply unit 82 is configured to supply the drive motor 66 with electrical energy during operation of the turbomolecular pump 10.

In Fig. 2 a first embodiment of a stator 26 is shown. The stator disc 26 is formed partially annular, defines a plane and has a circular outer periphery 84 defining an outer radius and a circular inner periphery defining an inner radius ( Fig. 2b ). Furthermore, the stator 26 is integrally formed and produced by means of a stamping bending process of a metal sheet. Circumferentially extending recesses 86 are provided in the stator disk 26 in the region of the outer circumference 84, which are separated from one another by webs 88, which in turn connect blades 90 to an outer edge region 91 of the stator disk 26.

The circumferentially extending recesses 86 in each case pass centrally into radial recesses 92, whereby approximately T-shaped recesses are formed, which separate the respective adjacent blades 90 from each other.

The blades 90 are each rotated about the webs 88 and inclined to the plane defined by the stator 26 level ( Fig. 2a ).

At the radially outer edge of the recess 86, a circumferentially extending fold 94 is bent downwards ( Fig. 2a ). The fold 94 extends in the circumferential direction over the entire length of the recess 86 and serves as a securing device. The securing device can include further folds 94. To secure the stator 26, the fold engages, for example, in a corresponding recess of a spacer ring 28, as based on Fig. 6 is explained in more detail.

In the manufacture of the stator disc 26, the crease 94 is formed of material which emerges from the outer edge region 91 and is punched and bent to form the recess 86.

Fig. 3a and Fig. 3b show a second embodiment of a stator 26, which differ from the in Fig. 2 shown embodiment differs in that instead of the fold 94 two lugs 96 are provided, each of which shown Bars 88 emerge. The lugs 96 together with at least two further, not shown, from the webs 88 resulting, circumferentially spaced lugs 96, the securing device.

In Fig. 4a and 4b a third embodiment of a stator disc 26 is shown, which differs from the first embodiment in that in the in Fig. 4a and 4b shown area a projection 98 is provided which is S-shaped. The protrusion 98 shown forms together with at least one further protrusion 98 (not shown) and preferably at least two further protrusions 98 (not shown) the securing device. The S-shaped projection 98 includes a circumferentially extending portion 99a in the plane of the stator disc 26 and a portion 99b spaced parallel to the plane, which are interconnected by a transition portion 99c. The S-shaped projection 98 is formed of material of the stator disc 26, which emerges from the webs 88 and was punched and bent to form the recesses 86.

Also, the S-shaped projection 98 allows a bayonet-like locking of the stator 26 on a spacer ring 28th

In addition, the S-shaped projection 98 is plastically deformable or bendable within certain limits, as indicated by arrows in FIG Fig. 4b is clarified. Due to the deformability of the projection 98 during assembly of the turbomolecular pump 10 or even in the manufacture of the stator 26 can be adapted to the position of an associated recess of the spacer ring 28.

Fig. 5 shows a fourth embodiment of a stator 26th In Fig. 5a are in each case two semicircular stator discs 26a, 26b shown, which rest in a transition region 106 to each other. The stator disks 26a, 26b have an inner periphery 108 and an outer periphery 84. A variety of Blades 90 are outwardly defined by circumferentially extending recesses 86, by radially extending recesses 92, and by inner circumferentially extending recesses 110.

Fig. 5b represents a view in the direction of arrows B of Fig. 5a Here it is particularly easy to see that the blades 90 are employed relative to the plane formed by the stator 26.

Fig. 5c shows a radial section through the stator disc 26. In this case, the inner circumference 108 is located in Fig. 5c above and the outer circumference 84 below. The outer periphery 84 is formed as a circumferential bent over collar 112 which extends at least approximately perpendicularly away from the plane of the stator disc 26. The circumferential collar 112 serves as a securing device and engages in the installed state in a circumferential groove of a spacer ring 28, whereby the stator disc 26 is secured against any movement in the plane.

Fig. 6 shows the interaction of the stator 26 of Fig. 2 with an adjacent spacer ring 28, wherein the fold 94 of the stator 26 engages in a recess of the spacer ring 28, here a circumferential groove 104. Alternatively, it could be in the recess but also a slot or a hole. By the engagement of the fold 94 in the groove 104, a movement of the stator disc 26 in the radial direction relative to the spacer ring 28 is prevented, in Fig. 6 So right or left. By using at least two folds 94 offset by 90 ° in the circumferential direction, any radial displacement of the stator disk 26 relative to the spacer ring 28 is prevented according to the invention.

Instead of the fold 94, at least one nose, L or S-shaped projection 96, 98 and / or circumferential collar 112, which is offset by 90 ° in the circumferential direction, can engage in the groove 104.

In addition, the blades 90 bear against a radially inner wall 106, which delimits the groove 104 radially on the inside. The wall 114 extends in the circumferential direction of the spacer ring 28 and forms a stop for the blades 90 of the stator 26. By the concerns of the blades 90 on the wall 114, the stator 26 is secured against radial movement away from the axis of rotation 20.

When assembling rotor disks 24, stator disks 26 and spacer rings 28, the securing devices of the stator disks 26 engage in the grooves 104 of the spacer rings 28. By the cooperation of securing devices and grooves 104, the radial displacement of the stator disks 26 is prevented, whereby the package of rotor disks 24, stator disks 26 and spacer rings 28 without the risk of jamming with the housing 16 can be introduced into the same. If the disk package is installed in the housing 16 of the turbomolecular pump 10, then the stator disks 26 are fixed by the housing 16 and the spacer rings 28.

Fig. 7 shows a fifth embodiment of a stator 26th This embodiment differs from the fourth embodiment according to Fig. 5 in that the semicircular stator disks 26a, 26b ( Fig. 7a ) are free at their ends in the region of the outer circumference 84 and the inner circumference 108, so that the stator disks 26a, 26b do not bear directly against one another, but define a gap 116 between them.

When viewed in the circumferential direction, each semicircular stator disk 26a, 26b comprises a bent nose 118, which protrudes from the plane defined by the stator disk 26 and forms a securing device. The area marked by the letter A of Fig. 7a and thus the nose 118 is in Fig. 7c in side view and in Fig. 7d shown in more detail in plan view.

In Fig. 7b is a side sectional view of the semicircular stator discs 26a, 26b and their interaction with a spacer ring 28 is shown. The semicircular stator disks 26a, 26b have stator blades 90 projecting out of the plane between the inner circumference 108 and the outer circumference 84, which have approximately a rectangular cross section.

If the semicircular stator disks 26a, 26b contact the spacer ring 28, the lugs 118 engage with a radially outwardly pointing step 122 and the stator blades 90 engage with a radially inwardly pointing double stage 124 of the spacer ring 28. The outer profile of the stator blades 90 is adapted to the double stage 124.

The abutment of the semicircular stator discs 26a, 26b on both the outwardly facing step 122 and the inward pointing step 124 prevents radial displacement of the semicircular stator discs 26a, 26b.

Fig. 8 shows a sixth embodiment of a stator 26, in contrast to the embodiment of Fig. 7 a plurality of parallel offset to the outer periphery 84 bent tips, teeth or projections 128 ( Fig. 8a ). Recesses 126 each ensure the flatness of the zones 128 surrounding the tips 128 of the outer edge region 91, since the shaping of the tips 128 can lead to the formation of beads in the area of the bending edge.

The tips 128 engage in recesses of the axially adjacent spacer ring 28, which are designed as radially encircling knurling 130 ( Fig. 8b ).

In particular, a plurality of tips, teeth or projections 128 may be provided which enclose an angle of 90 ° with each other. This way will a movement, both displacement and rotation, prevents the stator 26 in the plane defined by it by engaging the projections 128 in the knurling 130 of the spacer ring.

LIST OF REFERENCE NUMBERS

10

Turbo molecular pump

12

inlet flange

14

pump inlet

16

casing

18

rotor

20

axis of rotation

22

rotor shaft

24

rotor disc

26, 26a, 26b

stator

28

spacer

30

rotor hub

32

Holweckrotorhülse

34

Holweckrotorhülse

36, 38

Holweckstatorhülse

40

roller bearing

42

Permanent magnetic bearings

44

Rotor-side bearing half

46

stator side half

48

magnetic ring

50

magnetic ring

52

bearing gap

54

safety bearing

56

spray mother

58

absorbent disc

60

engine compartment

62

Siegbahn stage

64

Sealing gas inlet

66

drive motor

68

motor stator

70

core

72

Kitchen sink

74

Permanent magnet assembly

75a

soft magnetic inference

75b

permanent magnet

76

motor gap

78

balancing ring

80

encapsulation

82

Control and power supply unit

84

outer circumference

86

in the circumferential direction recess

88

web

90

shovel

91

outer edge area

92

radial recess

94

wrinkle

96

straight nose

98

S-shaped projection

99a

circumferentially extended section

99b

parallel spaced section

99c

Transition section

104

groove

106

Transition area

108

inner circumference

110

inner circumferential recess

112

collar

114

wall

116

gap

118

curved nose

122

outer stage

124

inner double stage

126

recesses

128

sharp lead

130

knurling

Claims (15)

A stator disk (26) for a turbomolecular pump (10), wherein the stator disk (26) extends in a part-annular manner in a plane, has an inner radius and an outer radius and comprises a securing device (94, 96, 98, 112, 118, 128), by means of which the stator disc (26) can be secured at least against radial displacement in the plane relative to an adjacently arranged spacer ring (28). Stator disc (26) according to claim 1,
characterized in that
the securing device (94, 96, 98, 112, 118, 128) comprises at least two, in particular three, projections (94, 96, 98) projecting out of the plane. Stator disc (26) according to claim 2,
characterized in that
at least two projections (94, 96, 98, 128) with the center of curvature of the stator disc (26) enclose an angle of not equal to 180 °. Stator disc (26) according to claim 3,
characterized in that
the angle is 75 ° to 105 ° and preferably 90 °. Stator disc (26) according to one of the preceding claims,
characterized in that
the stator disc (26) is integrally formed. Stator disc (26) according to one of the preceding claims,
characterized in that
the securing device (94, 96, 98, 112, 118, 128) is formed by bent-over material of the stator disk (26). Stator disc (26) according to claim 6,
characterized in that
formed by the bent material in a plane recess (86, 92, 110) of the stator disc (26) is formed. Stator disc (26) according to one of claims 2 to 7,
characterized in that
a section (99b) of at least one of the projections (94, 98) extends at least partially parallel to the plane. Stator disc (26) according to one of the preceding claims,
characterized in that
the securing device (94, 96, 98, 112, 118, 128) is constructed in the manner of a bayonet catch. Stator disc (26) according to claim 1,
characterized in that
the securing device (94, 96, 98, 112, 118, 128) forms a peripheral elevation (112). Stator disc (26) according to one of the preceding claims,
characterized in that
the securing device (94, 96, 98, 112, 118, 128) comprises at least two recesses (86, 92, 110) in the stator disk. Stator disc (26) according to one of the preceding claims,
characterized in that
the securing device (94, 96, 98, 112) is arranged in the region of an outer edge (91) of the stator disk (26) and / or the securing device (94, 96, 98, 112) has a knurling (130) and / or a toothing (128) in the region of an outer edge (91) of the stator disc (26). Method for producing a turbomolecular pump (10) provided stator disc (26) which extends in a part-annular manner in a plane having an inner radius and an outer radius and a securing means (94, 96, 98, 112, 118, 128), by means of which the stator disc (26) can be secured at least against radial displacement in the plane relative to an adjacently arranged spacer ring (28),
characterized in that
the securing device (94, 96, 98, 112, 118, 128) and at least one blade (90) of the stator disk (26) are formed by punching or laser cutting and subsequent bending. Turbomolecular pump (10) with at least one stator disk (26) according to one of claims 1 to 12 and a spacer ring (28),
characterized in that
the securing means (94, 96, 98, 112, 118, 128) and the spacer ring (28) cooperate to secure the stator disc (26) against in-plane movement. Turbomolecular pump according to claim 14,
characterized in that
the stator disc (26) comprises a securing device (94, 96, 98, 112, 118, 128) which cooperates with at least one recess (104) of the spacer ring (28).

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