EP3792495A1 - Side channel machine (compressor, vacuum pump or blower) with a bleed channel in the stripper - Google Patents

Abstract

The invention relates to a side channel machine which has a housing (4a), a side channel (28) located in the housing (4a) for guiding a gas and at least one in the housing (4a) in flow connection with the side channel (28) ) has formed gas inlet opening (34). Furthermore, the side channel machine has at least one gas inlet connector (29a) adjoining the at least one gas inlet opening (34). The side channel machine also comprises at least one gas outlet opening (33) and at least one gas outlet nozzle (31a) adjoining the at least one gas outlet opening (33). Furthermore, the side channel machine has an impeller rotatable in the housing (4a) with impeller blades which are arranged in the side channel (28) and delimit the impeller cells for conveying the gas in the impeller cells from the at least one gas inlet opening ( 34) to the at least one gas outlet opening (33). The side channel machine also has at least one interrupter (39) arranged between the at least one gas inlet opening (34) and the at least one gas outlet opening (33).

Description

The present patent application takes priority over the German patent application DE 10 2015 213 549.7 claim, the contents of which are incorporated herein by reference.

The invention relates to a side channel machine.

Side channel machines are generally known from the prior art. Side channel machines are able to convey or compress gas.

Generic side channel machines are from the DE 103 34 950 A1 , DE 197 08 953 A1 , DE 103 34 812 A1 or. DE 199 06 515 C1 for example known.

The invention is based on the object of providing a side channel machine which is particularly efficient and operates extremely quietly. Furthermore, the side channel machine should have a very high power density.

According to the invention, this object is achieved by the features specified in independent claim 1. Geometry optimization and targeted flow guidance of the side channel machine bring about an improvement of at least one performance parameter of the same. Advantageously, the power density, the efficiency and / or the noise development of the side channel machine is improved compared to conventional side channel machines. The gas to be conveyed is preferably air or a technical gas. The side channel machine is preferably designed as a side channel blower or side channel compressor executed. It is advantageous if the side channel machine is able to work in vacuum and / or compressor mode.

The side channel machine is designed in one or more stages.

The at least one gas inlet opening and the at least one gas outlet opening are arranged at a distance from one another in the flow direction of the gas about the axis of rotation. It is advantageous if there is an angle about the axis of rotation of at least 170 ° between them.

The impeller is advantageously in direct or indirect drive connection with a motor or drive.

The at least one interrupter is preferably mounted on the housing or is an integral part of the same.

The at least one gas inlet connector and / or the at least one gas outlet connector is / are preferably mounted on the housing or an integral part of the same.

During operation of the side channel machine, the gas is conveyed from the at least one gas inlet opening in a flow direction around the axis of rotation to the at least one gas outlet opening which is arranged downstream of the at least one gas inlet opening. The gas is thus guided in the side channel in an essentially ring-like manner. In this case, it is preferably pressed in the side channel by the centrifugal force that occurs radially outwards and then again to the radially inner region of the side channel with respect to the axis of rotation out, where it re-enters impeller cells between adjacent impeller blades and is again subject to centrifugal force.

It is advantageous if there are two gas inlet openings which are conveniently arranged next to one another and exactly one gas outlet opening and exactly one interrupter. Alternatively, more than two gas inlet openings, several gas outlet openings and / or interrupters are provided.

It is useful if the side channel machine has two impeller flows. For example, there is exactly one gas inlet connection which is designed to divide the gas, in particular evenly, between the two impeller flows. Alternatively, for example, a gas inlet connection is assigned to each impeller inlet.

Further advantageous refinements of the invention are specified in the subclaims.

It is advantageous if the at least one gas outlet connection is connected essentially tangentially to the side channel for the essentially tangential removal of the gas from the side channel. As a result of the essentially tangential arrangement of the at least one gas outlet connection on the side channel, pressure losses can be reduced, which leads to an improvement in the efficiency of the side channel machine. It is advantageous if the at least one gas outlet connection is connected absolutely tangentially to the side channel for the tangential removal of the gas from the side channel.

Advantageously, there is an angle about the axis of rotation between 280 ° and 320 °, more preferably between 290 ° and 310 °, between an upstream connection of the at least one gas outlet connector to the side channel and a downstream outlet of this gas outlet connector. This configuration also results in a reduction in pressure losses.

It is advantageous if the side channel is delimited by a cover that is radially outer with respect to the axis of rotation, the at least one gas outlet connecting to the cover essentially without a transition and essentially tangentially. As a result of this configuration, vortex shedding on the impeller blades and on the at least one gas outlet nozzle can be reduced, so that characteristic curve losses or pressure losses can be avoided. Furthermore, operating noises of the side channel machine can be reduced in this way. It is advantageous if the at least one gas outlet connection connects absolutely seamlessly and tangentially to a cover that delimits the side channel radially outward.

The side channel is preferably delimited by a base which is radially inner with respect to the axis of rotation, the at least one gas outlet connecting to the base in a substantially seamless and substantially tangential manner. The statements relating to the radially outer cover apply essentially analogously to dependent claim 5. It is advantageous if the at least one gas outlet connection connects absolutely seamlessly and tangentially to a base that delimits the side channel radially inward.

It is expedient if there is a flow cross-section in the at least one gas outlet connection in the flow direction of the gas, at least in some areas expanded, whereby preferably at least in an upstream starting area of the at least one gas outlet connector, opposing flow guide walls of the at least one gas outlet connector assume an angle of expansion of at most 11 °, more preferably of at most 9 °, to one another.

It is advantageous if the at least one gas outlet nozzle has at least one wall, preferably radially inner with respect to the axis of rotation, which runs essentially parallel to an absolute velocity vector of the gas flowing in the side channel adjacent downstream to the at least one interrupter. In this side channel machine, noises of the gas hitting the at least one interrupter can be prevented, which ensures particularly low-noise operation of the side channel machine. The gas thus favorably brushes along the at least one wall of the at least one gas outlet connection. It is advantageous if there is at least one wall on the at least one interrupter. It is expedient if the at least one wall runs absolutely parallel to an absolute velocity vector of the gas flowing in the side channel adjacent upstream of the at least one interrupter.

In the case of the side channel machine according to dependent claim 2, an interrupter gas mass flow can be discharged harmlessly into the at least one gas outlet nozzle. The at least one discharge channel is advantageously circular in cross section and preferably runs radially with respect to the axis of rotation. In particular, it extends straight.

The configuration of dependent claim 3 prevents gas from inadvertently escaping from the at least at certain operating points of the side channel machine a gas outlet nozzle flows back into the side channel or the at least one interrupter, which would be unfavorable in terms of efficiency and noise development. It is advantageous if the at least one valve is arranged essentially on the outlet side with respect to the flow of the gas on the at least one interrupter.

As a result of the configuration according to dependent claim 4, the gas can be sucked in a functionally reliable manner from at least one of the impeller cells adjacent to the at least one discharge channel. It is advantageous if the cross-sectional constriction necessary to form the Venturi arrangement is present in the at least one gas outlet nozzle.

As a result of the configuration according to dependent claim 5, the gas can be sucked off in a functionally reliable manner from at least one of the impeller cells adjacent to the at least one discharge channel.

As a result of the configuration according to dependent claim 6, the gas can be sucked in a functionally reliable manner from at least one of the impeller cells adjacent to the at least one discharge channel.

The spacing specified in dependent claim 8 between the downstream inlet opening of the at least one suction channel into the side channel and an upstream start of the at least one suction channel prevents the gas being sucked into the at least one suction channel.

According to dependent claim 9, at least one relief groove extending from the side channel is arranged in the at least one interrupter. By means of the at least one expansion groove, the expansion noise of the gas that arises during operation of the side channel machine due to the tensioned interrupter gas mass flow emerging from the impeller cells can be reduced. Furthermore, useful volume flows can be reduced by blocking an inflow cross-section.

Due to the configuration according to dependent claim 10, influences of the cell expansion in the at least one gas inlet connector can be avoided, so that the useful intake volume flow remains unaffected.

The configuration according to dependent claim 11 effectively prevents the occurrence of noise and turbulence.

The essentially tangential arrangement of the at least one gas inlet connector on the side channel according to dependent claim 12 enables pressure losses to be reduced, which leads to an improvement in the efficiency of the side channel machine. It is advantageous if the at least one gas inlet connection is connected absolutely tangentially to the side channel for the tangential introduction of the gas into the side channel.

Fig. 1

eine Ansicht einer herkömmlichen Seitenkanal-Maschine und eines an diese angeflanschten Antriebs, wobei die Seitenkanal-Maschine im Längsschnitt dargestellt ist,

Fig. 2

eine Draufsicht auf eine erfindungsgemäße Seitenkanal-Maschine gemäß einer ersten Ausführungsform,

Fig. 3

eine der Fig. 2 entsprechende Draufsicht auf eine erfindungsgemäße Seitenkanal-Maschine gemäß einer zweiten Ausführungsform,

Fig. 4

eine der Fig. 2 entsprechende Draufsicht auf eine erfindungsgemäße Seitenkanal-Maschine gemäß einer dritten Ausführungsform,

Fig. 5

eine vereinfachte Ansicht, die im Wesentlichen einen Gas-Auslassstutzen, einen Teil eines Laufrads und einen Teil eines Unterbrechers einer erfindungsgemäßen Seitenkanal-Maschine gemäß einer vierten Ausführungsform veranschaulicht,

Fig. 6

eine der Fig. 5 entsprechende vereinfachte Ansicht, die im Wesentlichen einen Gas-Auslassstutzen, einen Teil eines Laufrads und einen Teil eines Unterbrechers einer erfindungsgemäßen Seitenkanal-Maschine gemäß einer fünften Ausführungsform veranschaulicht,

Fig. 7

eine der Fig. 5 entsprechende vereinfachte Ansicht, die im Wesentlichen einen Gas-Auslassstutzen, einen Teil eines Laufrads und einen Teil eines Unterbrechers einer erfindungsgemäßen Seitenkanal-Maschine gemäß einer sechsten Ausführungsform veranschaulicht, und

Fig. 8

eine der Fig. 5 entsprechende vereinfachte Ansicht, die im Wesentlichen einen Gas-Auslassstutzen, einen Teil eines Laufrads und einen Teil eines Unterbrechers einer erfindungsgemäßen Seitenkanal-Maschine gemäß einer siebten Ausführungsform veranschaulicht.

In the following, preferred embodiments of the invention are described by way of example with reference to the accompanying drawings. Show:

Fig. 1

a view of a conventional side channel machine and a drive flanged to it, the side channel machine being shown in longitudinal section,

Fig. 2

a plan view of a side channel machine according to the invention according to a first embodiment,

Fig. 3

one of the Fig. 2 corresponding top view of a side channel machine according to the invention according to a second embodiment,

Fig. 4

one of the Fig. 2 corresponding top view of a side channel machine according to the invention according to a third embodiment,

Fig. 5

a simplified view which essentially illustrates a gas outlet nozzle, part of an impeller and part of a breaker of a side channel machine according to the invention according to a fourth embodiment,

Fig. 6

one of the Fig. 5 corresponding simplified view, which essentially illustrates a gas outlet nozzle, part of an impeller and part of an interrupter of a side channel machine according to the invention according to a fifth embodiment,

Fig. 7

one of the Fig. 5 corresponding simplified view, which essentially illustrates a gas outlet connection, part of an impeller and part of an interrupter of a side channel machine according to the invention according to a sixth embodiment, and

Fig. 8

one of the Fig. 5 Corresponding simplified view, which essentially illustrates a gas outlet nozzle, part of an impeller and part of a breaker of a side channel machine according to the invention according to a seventh embodiment.

First referring to Fig. 1 , which is used for general explanation, a conventional side channel blower 1 comprises an impeller 3 provided with impeller blades 2, which is rotatably mounted in a housing 4 about a longitudinal center axis or axis of rotation 5. A conventional drive 7 is used to drive the impeller 3 in rotation. The gas is accordingly conveyed in the housing 4.

The housing 4 comprises a first housing part 8 and a second housing part 9. The first housing part 8 and the second housing part 9 are shown in FIG Fig. 1 assembled and together enclose the rotatably drivable impeller 3 with the impeller blades 2, which is arranged on a drive shaft 10 in a rotationally fixed manner.

The impeller 3 is designed like a disk. It comprises an inner impeller hub 11 with a central, circular hub bore 12. The impeller hub 11 is formed by an inner hub base 13 that delimits the hub bore 12 radially outward and a radial, annular hub disk 14 adjoining this. Furthermore, the impeller 3 comprises a radially outer support ring 15, which adjoins the hub disk 14 on the outside and overlaps it on both sides in the direction of the longitudinal center axis 5. The support ring 15 carries a multiplicity of impeller blades 2, distributed in the circumferential direction, which protrude radially from the support ring 15. In particular, the impeller blades 2 are arranged equidistant from one another. The impeller blades 2 limit the impeller cells 50 in the circumferential direction.

The central hub bore 12 is used to accommodate the drive shaft 10. A conventional feather key connection is provided between the drive shaft 10 and the hub base 13 to transmit a torque applied by the drive shaft 10 to the impeller hub 11 to rotate the impeller 3.

The first housing part 8 has a central hub section 16 which delimits a partial hub receiving space 17 radially and axially. The hub section 16 is penetrated by a central shaft bore 18 which opens into the partial hub receiving space 17. An annular side wall 19 adjoins the hub section 16 and extends radially outward from the hub section 16. A circumferential channel section 20 adjoins the side wall 19 on the outside. The hub section 16, the side wall 19 and the channel section 20 are designed as a one-piece cast part and form the first housing part 8.

The second housing part 9, which is screwed to the first housing part 8 by means of a plurality of connecting screws 21, again has a central hub section 22 which delimits a partial hub receiving space 23 radially and axially. An annular side wall 24 adjoins the hub section 22 and extends radially outward. A circumferential channel section 25 is connected on the outside with the side wall 24. A roller bearing 26 for the drive shaft 10 is arranged in the hub section 22. The hub section 22, the side wall 24 and the channel section 25 are designed as a one-piece cast part and together form the second housing part 9.

The first housing part 8 and the second housing part 9 are connected to one another in the assembled state in such a way that the two partial hub receiving spaces 17, 23 jointly delimit a hub receiving space 27 and the two channel sections 20, 25 jointly define a side channel 28 limit for conveying the gas. The two side walls 19, 24 run parallel to one another, spaced apart. The side channel 28 extends annularly around the longitudinal center axis 5.

The second housing part 9 is advantageously designed as a housing cover which can be removed from the first housing part 8. Alternatively, a reverse configuration is possible.

The side channel blower 1 has two gas inlet connections 29. A gas inlet connection 29 is arranged on each housing part 8, 9. Each gas inlet connector 29 supplies a flood of the side channel 28. The gas to be conveyed can be introduced into the side channel fan 1 in a flow direction 30 via the gas inlet connector 29 when the side channel blower 1 is in operation.

The side channel blower 1 also has a gas outlet connection (not shown) which is formed by the two housing parts 8, 9. The gas outlet connection is in flow connection with the side channel 28. The gas can be discharged from the side channel blower 1 in a flow direction 32 via the gas outlet connection. The gas inlet stub 29 and the gas outlet stub extend essentially perpendicular to one another.

In the hub receiving space 27 delimited by the hub sections 16, 22, the side channel blower 1 is in the assembled state the hub foot 13 of the impeller 3 is arranged, the hub bore 12 being penetrated by the drive shaft 10. Between the spaced-apart side walls 18, 24 of the housing 4, the hub disk 14 of the impeller 3 extends radially outward from the hub base 13. The support ring 15 and the impeller blades 2 are located in the circumferential side channel 28.

Referring to FIG Fig. 2 a first embodiment of the invention described, which like the following embodiments in the side channel blower 1 according to Fig. 1 Can be applied. To the remarks on the side channel blower 1 according to Fig. 1 is referred. Identical components are given the same reference numerals as in the side channel blower 1 according to FIG Fig. 1 . Functionally identical, but structurally different components are given the same reference numerals with an "a" after them.

In the case of the side channel blower 1 a, the side channel 28 is spatially delimited radially inward by a floor 35 and radially outward by a ceiling 36 in relation to the longitudinal center axis 5. The floor 35 and the ceiling 36 lie opposite one another and run at a distance from one another, delimiting the side channel 28. They are formed on the housing 4a.

In the side channel blower 1a according to FIG Fig. 2 a gas outlet connection 31a is connected essentially tangentially to the side channel 28, so that gas conveyed in a conveying direction 6 leaves the side channel 28 via a gas outlet opening 33 in the housing 4a essentially tangentially. Between the side channel 28 and the gas outlet connection 31a, adjacent to the gas outlet opening 33, there is a gas deflection point at which the gas being conveyed is slightly radially outward with respect to the Longitudinal central axis 5 is deflected. The conveyed gas is slightly deflected both in the area of the floor 35 and in the area of the ceiling 36.

The gas outlet connector 31a expands substantially uniformly in the flow direction 32 of the gas.

How also from Fig. 2 As can be seen, the at least one gas inlet nozzle 29a is connected essentially tangentially to the side channel 28, so that the conveyed gas enters the side channel 28 essentially tangentially via at least one gas inlet opening 34 in the housing 4a.

Due to the essentially tangential arrangement of the connection pieces 29a, 31a on the side channel 28, pressure losses in the side channel blower 1a can be effectively reduced.

An interrupter 39 is arranged in the side channel 28 between the gas outlet opening 33 and the at least one gas inlet opening 34. The interrupter 39 has a side wall 40 adjacent to the gas outlet opening 33. Furthermore, the interrupter 39 has an inner wall 41 that is radially inner in relation to the longitudinal center axis 5 and a radially outer outer wall 42 opposite the inner wall 41.

Referring to FIG Fig. 3 described a second embodiment of the invention. Structurally identical components are given the same reference numerals as in the side channel blowers 1, 1a according to FIG Fig. 1 or 2. Functionally similar, but structurally different components are given the same reference numerals with a subsequent "b".

In the case of the side channel blower 1b, the at least one gas inlet nozzle 29a is again connected to the side channel 28 essentially tangentially.

The gas outlet connector 31b connects absolutely or completely tangentially to the side channel 28. According to Fig. 3 the connection between the side channel 28 and the gas outlet nozzle 31b is seamless. This applies to both the radially inner and the radially outer guidance of the gas in relation to the longitudinal center axis 5.

It is advantageous if the gas outlet connection 31b widens downstream to the gas outlet opening 33. Particularly preferably, an inner flow guide wall 37 of the gas outlet connector 31b, which adjoins the base 35, deviates by an angle b from a parallel to an opposite outer flow guide wall 38 of the gas outlet connector 31b, as in FIG Fig. 3 is shown in dashed lines. The angle b is a maximum of 9 °.

Between a connection 55 of the gas outlet connection 31b to the side channel 28 and the radially inner flow guide wall 37 at the outlet of the side channel blower 1b, there is advantageously a connection angle c about the longitudinal center axis 5, which is between 290 ° and 310 °.

Referring to below Fig. 4 a third embodiment of the invention will be described. Identical parts are given the same reference numerals as in the previous embodiments. Parts that are structurally different but functionally identical are given the same reference numerals with a "c" after them.

In the case of the side channel blower 1c according to Fig. 4 the interrupter 39c is penetrated by a discharge channel 43 which extends between the inner wall 41 of the interrupter 39c and the outer wall 42 of the interrupter 39c radially with respect to the longitudinal center axis 5. The discharge channel 43 has a cross-sectional area A.

A suction channel 44 adjoins the discharge channel 43 on the downstream side, radially on the inside, and opens into the side channel 28 at a distance from the discharge channel 43. The mouth or inlet opening 45 of the suction channel 44 into the side channel 28 is located approximately opposite the discharge channel 43. The inlet opening 45 is spaced from the discharge channel 43 by an angle d about the longitudinal center axis 5, which is between 120 ° and 140 °. The suction channel 44 has a larger, in particular significantly larger, cross-sectional area B than the discharge channel 43.

Gas is sucked in via the discharge channel 43 from an impeller cell 50 of the rotating impeller 3, which is located just adjacent to an inlet opening 56 of the discharge channel 43 which opens into the side channel 28. The gas transport can be achieved, for example, by means of corresponding pressure differences, in particular between inlet opening 56 and inlet opening 45. In particular, the pressure prevailing at the inlet opening 45 is lower than at the inlet opening 56. The impeller cells 50 are spatially delimited in the circumferential direction of the side channel 28 by adjacently arranged impeller blades 2. The gas then flows in the suction channel 44 and re-enters the side channel 28 via the inlet opening 45.

Referring to FIG Fig. 5 a fourth embodiment of the invention is described. Identical parts are given the same reference numbers as in the previous embodiments. Parts that are structurally different but functionally identical have the same reference numerals followed by a "d".

In the case of the side channel blower 1d according to FIG Fig. 5 the outer wall 42d of the interrupter 39d, which also forms the flow guide wall 37, extends parallel to an absolute velocity vector or to an absolute velocity direction 46 of the gas flowing immediately upstream to the interrupter 39d at the flow point P. The absolute velocity vector 46 is determined by adding the circumferential velocity of the Impeller 3 received about the longitudinal center axis 5 and the relative speed of the gas radially outward with respect to the longitudinal center axis 5.

Between the inner wall 41 and the outer wall 42d there is an angle e which is preferably between 15 ° and 40 °, more preferably between 20 ° and 30 °.

The gas outlet connector 31 can widen in the direction of flow 32.

Referring to FIG Fig. 6 a fifth embodiment of the invention is described. Identical parts are given the same reference numerals as in the previous embodiments. Parts that are structurally different but functionally identical have the same reference numerals followed by an "e".

In contrast to the embodiment according to Fig. 5 In the case of the side channel blower 1e, the discharge channel 43e is located in the interrupter 39e, which provides a flow connection between the side channel 28 and the gas outlet nozzle 31 manufactures. The discharge channel 43e extends radially or essentially radially with respect to the longitudinal center axis 5.

For a functionally reliable suction the following applies in particular: p _U > p _T , where pu is the pressure prevailing in the impeller cell 50 at the discharge channel 43e and p _{T is} the pressure prevailing downstream of the discharge channel 43e in the gas outlet connection 31.

V₁:

Ansaugvolumenstrom bzw. Absaugvolumenstrom in dem Abführkanal 43 e

u:

Umfangsgeschwindigkeit des Laufrads

A_K:

Querschnittsfläche des Seitenkanals 28 auf Druckseite

p₂/p₁:

Druckverhältnis über dem Seitenkanal-Gebläse 1e

D_i:

Durchmesser des Laufrads am Laufrad-Schaufel-Fuß

D_a:

Außendurchmesser des Laufrads

A discharge of the gas via the discharge channel 43e from the side channel 28 to the gas outlet connection 31 is particularly reliable if the following condition is also met: $${\mathrm{V}}_{\mathrm{1}}>\mathrm{u}\cdot {\mathrm{A.}}_{\mathrm{K}}\cdot \sqrt{\frac{{\mathrm{p}}_{\mathrm{2}}}{{\mathrm{p}}_{\mathrm{1}}}\cdot \left(\mathrm{1}-{\left(\frac{{\mathrm{D.}}_{\mathrm{i}}}{{\mathrm{D.}}_{\mathrm{a}}}\right)}^{\mathrm{2}}\right)}$$

V ₁ :

Suction volume flow or suction volume flow in the discharge channel 43 e

u:

Peripheral speed of the impeller

A _K :

Cross-sectional area of the side channel 28 on the pressure side

p ₂ / p ₁ :

Pressure ratio across the side channel blower 1e

D _i :

Diameter of the impeller at the impeller-blade foot

D _a :

Outside diameter of the impeller

The suction volume flow is thus dependent on the circumferential speed of the impeller, the cross-sectional area of the side channel on the pressure side, the pressure ratio over the side channel fan and the diameter of the Impeller at the impeller-blade base as well as the outer diameter of the impeller.

According to a preferred embodiment, a dead space trough 47 extends from the gas outlet connection 31 or the outer wall 42e of the interrupter 39e. The discharge channel 43e opens into the dead space trough 47.

In the dead space trough 47, an automatic valve plate 49 is fastened to the interrupter 39e via at least one fastening means 48, which, in its closed position, closes the discharge channel 43e at its downstream end area opposite its inlet opening 56. In the open position, the valve plate 49 is lifted from the interrupter 39e at least in some areas and thus releases the discharge channel 43e at least in some areas for the gas.

In the area of the dead space trough 47, the gas outlet connector 31 thus has an expanded cross-sectional area. When the side channel blower 1e is in operation, a gas dead space area arises in the dead space trough 47. The pressure of the gas is then reduced in the dead space trough 47, so that when the valve plate 49 is open, gas is sucked out of the impeller cell 50, which is currently adjacent to the discharge channel 43e. In its closed position, the valve plate 49 prevents the gas from flowing back unintentionally from the gas outlet connector 31 or the dead space trough 47 into the discharge channel 43e or the side channel 28.

Alternatively, a design without valve plate 49 is possible. The valve plate 49 can also in the embodiment according to Fig. 6 be present without dead space trough 47.

A_v:

Querschnittsfläche der Vena Contracta der Venturidüse in dem Gas-Auslassstutzen 31

A discharge of the gas via the discharge channel 43e from the side channel 28 to the gas outlet connection 31 is particularly reliable when the following condition is met: $${\mathrm{V}}_{\mathrm{1}}>\mathrm{u}\cdot {\mathrm{A.}}_{\mathrm{K}}\cdot \sqrt{\frac{{\mathrm{p}}_{\mathrm{2}}}{{\mathrm{p}}_{\mathrm{1}}}\cdot \frac{\mathrm{1}-{\left(\frac{{\mathrm{D.}}_{\mathrm{i}}}{{\mathrm{D.}}_{\mathrm{a}}}\right)}^{\mathrm{2}}}{{\left(\frac{{\mathrm{A.}}_{\mathrm{K}}}{{\mathrm{A.}}_{\mathrm{V}}}\right)}^{\mathrm{2}}-\mathrm{1}}}$$

A _v :

Cross-sectional area of the vena contracta of the Venturi nozzle in the gas outlet nozzle 31

The suction volume flow is therefore dependent on the circumferential speed of the impeller, the cross-sectional area of the side channel on the pressure side, the pressure ratio over the side channel fan, the diameter of the impeller at the impeller-blade base and the outer diameter of the impeller as well as the cross-sectional area of the vena contracta of the Venturi nozzle in the Gas outlet connection dependent.

Referring to FIG Fig. 7 a sixth embodiment of the invention is described. Identical parts are given the same reference numerals as in the previous embodiments. Parts that are structurally different but functionally identical have the same reference numerals followed by an "f".

Instead of the dead space trough 47 on the interrupter 39f, the side channel blower 1f has a flow-reducing projection 51 which jumps into the gas outlet connection 31. The discharge channel 43f also penetrates the Flow reduction projection 51. A valve plate 49 is preferably arranged on the flow reduction projection 51 again via at least one fastening means 48.

In the area of the flow-reducing projection 51, the gas outlet connector 31 has a reduced flow cross-section, so that there is a particularly high flow velocity of the conveyed gas. Conversely, there is consequently a reduced pressure there, so that gas is sucked out of the impeller cell 50 which is just adjacent to the discharge channel 43f via the discharge channel 43f into the gas outlet connection 31. A Venturi nozzle or arrangement is created in this way, as it were.

Referring to FIG Fig. 8 a seventh embodiment of the invention is described. Identical parts are given the same reference numerals as in the previous embodiments. Parts that are structurally different but functionally identical have the same reference numerals with a "g" after them.

In the interrupter 39g there is at least one stress-relieving groove 52 which starts from the side channel 28. Between an upstream starting point 53 of the expansion groove 52 and an axial or circumferential impeller cell opening 54, there is preferably a distance x which corresponds to at least 1.5 times the distance r between adjacent impeller blades 2 around the longitudinal center axis 5. In the conveying direction 6, the radial depth t of the relaxation groove 52 gradually increases in relation to the longitudinal center axis 5. The angle e of the expansion groove 52 is favorably based on the pressure ratio p _Z / p ₁ and the circumferential speed u of the impeller, where pz is the pressure prevailing in the impeller cells 50 and p _{1 is} the suction pressure of the side channel blower is. When the impeller cells 50 are relaxed, the circumferential speed of the impeller 3 and the flow speed are superimposed, so that transonic or even supersonic flows can also occur. The equation gives an estimate of the occurrence of supersonic flows: $$\mathrm{M.}\cdot {\mathrm{u}}_{\mathrm{crit}}=\mathrm{0},\mathrm{9}\cdot {\left(\frac{{\mathrm{p}}_{\mathrm{1}}}{{\mathrm{<figure-callout\; id="2"\; label="p"\; filenames="imgf0001.png,imgf0005.png"\; state="\{\{state\}\}">p</figure-callout>}}_{\mathrm{2}}}\right)}^{\mathrm{2},\mathrm{46}}$$

If M u> M u _crit , supersonic occurs. The at least one expansion groove 52 can then be dimensioned according to the known principles of the “Prandtl-Meyer corner flow”.

Combinations of the different embodiments are possible, in particular with regard to the different nozzles and interrupters.

Claims (12)

Side channel machine, comprehensive a) a housing (4), b) an essentially ring-like side channel (28) located in the housing (4; 4a; 4b; 4c) for guiding a gas, c) at least one gas inlet nozzle (29; 29a), d) at least one gas inlet opening (34) which is in flow connection with the side channel (28) and is formed in the housing (4; 4a; 4b; 4c) for guiding the gas out of the at least one gas inlet nozzle (29; 29a) in the side channel (28), e) at least one gas outlet opening (33) arranged in the housing (4; 4a; 4b; 4c) for discharging the gas from the side channel (28), f) at least one gas outlet nozzle (31; 31a; 31b; 31c) adjoining the at least one gas outlet opening (33), g) an impeller (3) rotatable about an axis of rotation (5) in the housing (4) with impeller blades (2) arranged in the side channel (28) and delimiting impeller cells (50) for conveying the impeller Cells (50) of gas located in the side channel (28) from the at least one gas inlet opening (34) to the at least one gas outlet opening (33), and h) at least one interrupter (39; 39c; 39d; 39e; 39f; 39g) arranged between the at least one gas inlet opening (34) and the at least one gas outlet opening (33) for preventing the gas from being transported from the at least one gas Outlet opening (33) to the at least one gas inlet opening (34). Side channel machine according to claim 1, characterized in that in the at least one interrupter (39; 39c; 39e; 39f) at least one discharge channel (43; 43e; 43f) for discharging the in at least one of the, straight to the at least one discharge channel ( 43; 43e; 43f) of adjacent impeller cells (50) of enclosed gas from the side channel (28) into the at least one gas outlet nozzle (31; 31a; 31b; 31c). Side channel machine according to Claim 2, characterized by at least one valve (49), in particular a plate valve, assigned to the at least one discharge channel (43e; 43f), for preventing the gas from flowing back out of the at least one gas outlet nozzle (31; 31a; 31b; 31c ) into the side channel (28). Side channel machine according to Claim 2 or 3, characterized by at least one Venturi arrangement for sucking the gas enclosed in at least one of the impeller cells (50) which is just adjacent to the at least one discharge channel (43e; 43f) from the side channel (28) into the at least one gas outlet nozzle (31; 31a; 31b; 31c) via the at least one discharge channel (43e; 43f). Side channel machine according to one of Claims 2 to 4, characterized by at least one dead space trough (47) arranged on the interrupter (39e) for sucking up the impeller cells (47) in at least one of the at least one discharge channel (43e) adjacent to the impeller. 50) enclosed gas from the side channel (28) into the at least one gas outlet nozzle (31; 31a; 31b; 31c) via the at least discharge channel (43e). Side channel machine according to Claim 2 or 3, characterized by at least one suction channel (44) adjoining the at least one discharge channel (43) for sucking up the impeller cells (44) adjacent to the at least one discharge channel (43) in at least one of the at least one discharge channel (43). 50) enclosed gas from the side channel (28) into the side channel (28) at a distance from the at least one discharge channel (43). Side channel machine according to claim 6, characterized in that a total cross-sectional area of the at least one suction channel (44) between 0.001 x total volume of the impeller cells (50) of the impeller (3) and 0.006 x total volume of the impeller cells ( 50) of the impeller (3). Side channel machine according to claim 7, characterized in that between a downstream inlet opening (45) of the at least one suction channel (44) into the side channel (28) and an upstream beginning of the at least one suction channel (44) an angle (d) about the axis of rotation (5) is between 90 ° and 170 °, more preferably between 120 ° and 140 °. Side channel machine according to one of the preceding claims, characterized in that at least one relief groove (52) starting from the side channel (28) is arranged in the at least one interrupter (39g). Side channel machine according to claim 9, characterized in that between an upstream beginning (53) of the at least one relaxation groove (52) and an impeller cell opening (54) at least one of the impeller cells (50) adjacent to the at least one relaxation groove (52) in the circumferential direction around the longitudinal center axis (5) a minimum distance (x) of 1.1 to 2.0 times, more preferably of 1.4 times to 1.6 times the distance (r) between adjacent impeller blades (2) to one another in the circumferential direction about the axis of rotation (5). Side channel machine according to claim 9 or 10, characterized in that the at least one relaxation groove (52) is shaped in such a way that the gas is able to at least partially along the wall of the interrupter (39g) delimiting the at least one relaxation groove (52) to brush. Side channel machine according to one of the preceding claims, characterized in that the at least one gas inlet connector (29; 29a) is connected essentially tangentially to the side channel (28) for the essentially tangential introduction of the gas into the side channel (28).

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