Side channel compressor, method of operating side channel compressor, and fuel cell system

Abstract

A side channel compressor for a fuel cell system for compressing a gaseous medium has a housing with a first housing part having a bearing journal extending along an axis of rotation and having a journal root section and a journal main section, and a second housing part having a bearing journal extending along an axis of rotation. A bearing inner ring of the bearing device is arranged on the journal main section, and a compressor wheel assembly having a compressor wheel is arranged in the housing on a bearing outer ring of the bearing device in a rotatable manner about an axis of rotation and can be driven by means of a drive, the first housing part is at least indirectly tensioned with the bearing device via a fastening element, in particular in the direction of the axis of rotation, a spring element is arranged between the bearing device and the first housing part. The heating disc is arranged in the region of the journal root section, and the heating disc extends around the bearing journal in particular in a circumferential manner. The heating disc is attached to the spring element in the direction of the rotation axis.

Description

Technical Field

[0001] The invention relates to a side channel compressor for a fuel cell system, which serves to compress a gaseous medium. The invention also relates to a method for operating a side channel compressor, in particular a cold start procedure, and a fuel cell system having a side channel compressor according to the generic method. Background Art

[0002] Rising fuel prices and legal requirements to limit CO2 emissions have led car manufacturers to increasingly investigate drive systems that use renewable energy. Hydrogen technology is a promising approach for many reasons, since hydrogen is available almost unlimitedly as an energy carrier and does not produce harmful exhaust gases when burned.

[0003] The direct combustion of hydrogen is a highly complex and currently almost uncontrollable process, and drive systems are becoming increasingly important in which electrical energy is first generated using hydrogen, which can then be used to drive an electric motor for driving the motor vehicle. For this purpose, these drive systems have fuel cells.

[0004] According to the principle, the fuel cell system has a hydrogen inlet, through which hydrogen can be supplied to the fuel cell. The fuel cell system has an anode on the hydrogen inlet side. In order to supply oxygen, the fuel cell system has an oxygen inlet. On the oxygen inlet side, the fuel cell system has a cathode. Finally, the fuel cell system has an exhaust gas outlet for discharging the exhaust gas of the fuel cell. Here, the exhaust gas is mainly water and unconsumed air as a combustion product of the fuel cell. Since not all hydrogen supplied to the fuel cell can be burned during the reaction in the fuel cell, unburned or unconsumed hydrogen is also present in the exhaust gas.

[0005] In order to reduce the hydrogen consumption in fuel cells, it is now common to recirculate the unconsumed hydrogen. For this recirculation, a recirculation blower is used, which sometimes has a so-called "side channel compressor".

[0006] Side channel compressors are known in various embodiments. A side channel compressor is a turbocompressor which can be divided into “planetary compressors” and “peripheral compressors” depending on the impeller used and the fluid guidance.

[0007] The fluid to be delivered is supplied to the working chamber of the side channel compressor via an inlet connection, which is coupled to the exhaust gas outlet of the fuel cell system in a fluidic manner for this purpose. The compressor wheel assembly of the side channel compressor, which is designed as an impeller, is arranged in the working chamber and can be driven and thus rotated by means of an electric motor. The compressor wheel assembly rotates to an axially arranged flow channel, which is lateral to one side or to both sides and is also referred to as a "side channel".

[0008] In this way, the rotating compressor wheel assembly transfers energy to a portion of the delivery flow. The fluid circulates in the blades of the compressor wheel assembly and in the side channel, and forms a circulating flow. Energy is transferred from the circulating flow to the delivery flow in the side channel by pulse exchange. Thus, velocity energy is converted into pressure energy. Here, this energy transfer takes place several times over the entire length of the side channel, so that a large energy transfer can be achieved. As a result, a pressure increase occurs at the outlet connection of the side channel compressor compared to the inlet connection.

[0009] Document DE 10 2018 222 102 A1 discloses a conventional side channel compressor. This side channel compressor may have the following disadvantages: when using the axial fixation of the rolling bearing on the bearing journal at the bottom of the housing, strong tension and therefore excessive bearing preload of the bearing occur. In particular, due to the preload of the fixing element, the fixing element is implemented as a central screw, for example. This may lead to the bearing device being damaged due to the tension of the bearing ring, in particular the corresponding inner bearing ring and the outer bearing ring, wherein the rolling bearing body inside the bearing is damaged. This leads to a reduced bearing service life and therefore to an increased failure probability of the side channel compressor. In addition, DE 10 2018207 891 A1 discloses a side channel compressor, in which a spring element is located between the housing part and the bearing. In this case, it may occur that at low temperatures, in particular temperatures below 0° C., the spring element freezes on the bearing, in particular on the inner bearing ring or on the outer bearing ring. In the event of an unintended, rotating bearing inner ring and / or bearing outer ring, damage to the spring element may occur, since the spring element rotates along with it. This may lead to damage to the spring element. In particular, if the spring element is designed as a wave spring, the wave spring, in particular the individual windings of the wave spring, may become tightened, which may lead to severe damage and / or failure of the wave spring and thus to severe damage and / or failure of the side channel compressor. Summary of the invention

[0010] The invention relates to a side channel compressor for a fuel cell system for compressing a gaseous medium, a method for operating a side channel compressor, in particular a cold start procedure, and a fuel cell system having a side channel compressor. Further features and details of the invention are apparent from the description and the drawings. Features and details described in the context of the side channel compressor according to the invention are of course also applicable in the context of the fuel cell system according to the invention, and vice versa, so that reference is always made to one another or can be made to one another with regard to the disclosure of the individual inventive aspects.

[0011] According to a first aspect of the present invention, a side channel compressor for a fuel cell system is provided, which is used to compress a gaseous medium. The side channel compressor has a housing, which has a first housing part and a second housing part, wherein the first housing part has a bearing journal extending along the rotation axis R, and the bearing journal has a journal root section and a journal main section. At least one bearing inner ring of a bearing device is arranged on the journal main section, wherein the compressor wheel structure group is arranged on the bearing outer ring of the bearing device in a manner that can rotate around the rotation axis R in the housing. In addition, the compressor wheel structure group can be driven by means of a drive, wherein the first housing part is at least indirectly tensioned with the bearing device via a fastening element, and wherein, in particular in the direction of the rotation axis R, a spring element is arranged between the bearing device and the first housing part.

[0012] The housing is formed by a first housing part and a second housing part. According to the invention, it can be provided, but not necessarily required, that the first housing part and / or the second housing part have further housing parts, which can be designed in particular as a housing cover, a housing wall or the like. Preferably, the first housing part defines a preassembled assembly of the side channel compressor, which assembly has a bearing device and a compressor wheel assembly. A working chamber for the compressor wheel assembly is formed by the housing, preferably by the mutual cooperation of the first housing part and the second housing part.

[0013] Preferably, the working chamber is designed to be fluid-tight, except for the working chamber inlet and the working chamber outlet. In the context of the present invention, fluid-tight is also understood to mean that the tightness is maintained at an operating pressure of the side channel compressor that is higher than the ambient pressure. In order to ensure the tightness, preferably a sealing device, such as a sealing ring, in particular a sealing ring made of silicone or rubber or the like, is arranged between the first housing part and the second housing part. Preferably, the first housing part is formed essentially or predominantly of aluminum. Preferably, the second housing part is formed essentially or predominantly of aluminum.

[0014] The bearing journal is configured as a sub-region of the first housing component and extends away from the inner wall of the first housing component. According to the invention, the bearing journal is configured integrally with the first housing component. Alternatively, the bearing journal can also be arranged on the first housing component in a material-locked manner (e.g., by welding) or in a force-locked manner (e.g., by screwing or pressing). The bearing journal extends from the inner wall of the first housing component from the journal root section via the journal main section to the journal end section.

[0015] The bearing device has a bearing inner ring and a bearing outer ring. Preferably, a plurality of rolling bodies, such as balls, rollers, cylinders or the like, are arranged between the bearing inner ring and the bearing outer ring so as to support the bearing outer ring on the bearing inner ring as close to clearance as possible and ensure relative rotation between the bearing inner ring and the bearing outer ring.

[0016] The bearing inner ring of the bearing device is preferably arranged with a loose fit on the main journal section. It is also possible to arrange a plurality of bearing inner rings, preferably each with a loose fit, on the main journal section. The loose fit is preferably designed such that when the tension is released, an easy movement of the bearing device on the bearing journal is ensured, for example manually, and a tilting of the bearing inner ring on the bearing journal is prevented.

[0017] The compressor wheel assembly is preferably arranged on the bearing outer ring of the bearing device with a press fit. The press fit is preferably designed in such a way that a displacement of the compressor wheel assembly on the bearing device is prevented in a force-locking manner. Alternatively, the compressor wheel assembly can be arranged on the bearing outer ring with a loose fit and can be secured by a retaining device to prevent axial slipping from the bearing device.

[0018] According to the invention, the side channel compressor is designed such that at least one heating disk is arranged in the region of the journal root section and abuts against the spring element in the direction of the axis of rotation R, the heating disk extending in particular circumferentially around the bearing journal. In this way, the following advantages can be achieved: in the case of a cold start and / or a cold start procedure, at temperatures below 0° C., the heating disk can be heated, wherein the heating disk transfers its thermal energy to the spring element and / or other contacting components. In this way, contact points that are connected to one another due to freezing and / or adhesion, for example due to existing ice bridges, are removed. When the water in the side channel compressor freezes, in particular at temperatures below 0° C., these ice bridges can form, wherein a positive and / or non-positive connection between components, for example between the spring element and the bearing inner ring, is formed by means of these ice bridges. This in turn leads to the spring element rotating together with the bearing inner ring, whereby the bearing inner ring, the spring element or other components are damaged. In addition, the spring element can be damaged by so-called “tightening”, which can lead to complete failure of the spring element and also damage surrounding components. Therefore, the following advantages are achieved by the configuration of the side channel compressor according to the invention: the heating plate can be heated by introducing external energy, thereby preventing the spring element from rotating together and / or tightening. Therefore, by heating the heating plate, it is possible to quickly eliminate the ice bridge between the spring element and the other components, in particular by melting. In addition, other phenomena, such as force-locking and / or form-locking effects caused by adhesion, cold welding or other effects, are at least almost eliminated by heating the heating plate. As a result, a reliable and fast cold start procedure of the side channel compressor and the fuel cell system can be carried out. This leads to a higher reliability of the side channel compressor. Therefore, the service life of the spring element and therefore the service life of the entire side channel compressor can be increased.

[0019] According to an advantageous embodiment of the side channel compressor, the heating disk is arranged in the direction of the rotation axis R between the spring element and the bearing inner ring and / or between the spring element and the first housing part, in particular in the region of the corresponding contact point. In this way, the region in which the spring element is at least indirectly in contact with another component, such as the bearing inner ring or the first housing part, in particular via the corresponding heating element, can be heated by means of the heating element. In particular, in the case of a cold start of the entire vehicle and / or a cold start procedure, in which the vehicle is started at a temperature below the freezing point of water, this is advantageous because any ice bridges that may exist between the spring element and the other component, such as the bearing inner ring, are thawed. For example, non-positive and / or positive connections between the spring element and, for example, the bearing inner ring, which are caused by adhesion, cold welding or other effects, are also removed in that the heating disk can be heated. Thus, for example, the spring element is prevented from rotating together with the bearing inner ring, whereby damage to the spring element due to tightening can be prevented. In this way, the following advantages can be achieved: the probability of damage to the spring element is reduced, whereby the probability of failure of the entire side channel compressor can be reduced.

[0020] According to an advantageous development of the side channel compressor, the heating plate is in contact with the spring element and with the contact surface of the corresponding inner ring of the bearing, in particular so that the spring element does not directly contact the contact surface. In this way, the following advantages can be achieved: the spring element does not directly contact and / or contact the inner ring of the bearing, because the heating plate is located between the inner ring of the bearing and the spring element. In this way, a "joint rotation" of the spring element and the inner ring of the bearing, which can rotate in a rotational manner relative to the bearing journal in a certain operating state of the side channel compressor, is prevented, because this "joint rotation" is absorbed by the spring element cover and is thus compensated. In addition, a spatial separation of the bearing seal and the spring element can be achieved, so that possible damage to the bearing seal rotating with the outer ring of the bearing is prevented by a stationary spring element, in particular by frictional contact. In this way, the service life of the spring element and / or the bearing seal and / or the bearing device can be improved, thereby reducing the probability of failure of the side channel compressor. Furthermore, by positioning the heating plate at this point, an improved elimination of ice bridges in the region of the spring element by melting can be achieved, whereby the service life of the spring element and thus of the side channel compressor can be extended.

[0021] According to a particularly advantageous embodiment of the side channel compressor, the heating plate is in contact with the spring element and with the inner wall of the first shell, in particular so that the spring element does not directly contact the inner wall. In this way, the following advantages can be achieved: the spring element is in direct contact with the first housing part, in particular the inner wall, in particular frictional contact. The heating plate is located between the spring element and the first housing part. Therefore, wear, in particular frictional wear, of the spring element and / or the first housing part at the contact point can be prevented. In addition, the heating plate can be made of a specially hardened material so that at least almost no material loss occurs. If there is no heating plate, material loss occurs, namely by the so-called "embedding" of the spring element on the first housing part, whereby, on the one hand, chips are generated, which are guided by the bearing device and other components of the side channel compressor. On the other hand, the spring element is extended by the embedding, so that the prestressing force acting on the bearing device is reduced. Since the "embedding" of the spring element can be prevented by using the heating plate, the failure probability of the spring element, the bearing device and the entire side channel compressor can be reduced. Furthermore, positioning the heating plate at this location offers the advantage that the spring element is prevented from freezing to the first housing part, in particular due to ice bridges, since the heating plate can be heated within the framework of a cold start procedure and thus can achieve an improved elimination of ice bridges in the region of the spring element by melting, thereby enabling the service life of the spring element and therefore of the side channel compressor to be extended.

[0022] According to a particularly advantageous construction of the side channel compressor, at least one heating disk has a magnetic material, in particular a ferromagnetic material. In this way, the following advantages can be achieved: the heating disk can be heated inductively by means of an induction field without the need for electrical contacts, for example in the form of sliding contacts or in the form of carbon brushes. Sliding contacts are necessary because relative movements of the heating disk relative to the housing and / or the side channel compressor occur, but this disadvantageous embodiment can be prevented by means of the embodiment of the invention in which the corresponding heating disk is formed of ferromagnetic material. Here, by means of the generated magnetic alternating field, so-called eddy currents are generated in the region of the heating disk. The alternating field or induction field itself can be realized, for example, by the stator of the drive and the corresponding control of the stator. However, alternatively, an induction field can also be generated by other electrical components of the side channel compressor, which heats the ferromagnetic heating disk. In addition, the heat energy transfer from the heating disk to other components of the side channel compressor can be realized, such as spring elements or bearing inner rings. Therefore, the failure of the spring element due to "tightening" or due to damage caused by freezing and / or ice bridges can be reduced, thereby improving the service life of the side channel compressor.

[0023] According to a particularly advantageous embodiment of the side channel compressor, the spring element comprises a magnetic material, in particular a ferromagnetic material or chrome steel. In this way, the advantage can be achieved that the energy from the generated induction field can be introduced directly into the spring element, which leads to heating of the spring element. Thus, existing ice bridges can be eliminated.

[0024] In a particularly preferred embodiment of the invention, it can be provided in the side channel compressor that the spring element is designed as a wave spring. Wave springs are available at low cost and have a characteristic curve that is favorable for the application. This has the advantage that a reliable and constant provision of the tensioning force and / or the bearing prestressing by means of the wave spring is ensured by simple means and in a cost-effective manner.

[0025] According to an advantageous method for operating a side channel compressor, in particular in the framework of a cold start procedure, the stator is energized so that an induction field, in particular an induction magnetic field, is formed. In this case, an inductive energy transfer to the corresponding heating disk is performed, wherein the heating disk is heated as a result. In an exemplary embodiment of the method, the coils of the stator can be energized for a short period of time, so that the heating disk is heated due to the generated power loss. In addition, in another possible embodiment, the stator can be energized by means of an advantageous method so that inductive heating of the heating disk is achieved, wherein in particular a transfer of heat energy is achieved from the heating disk to the spring element. As a result, any ice bridges that may be present melt and the liquid changes from a solid aggregate state to a liquid aggregate state and can be discharged, for example by means of a purge valve and / or a drain valve present in the fuel cell system. In this way, the service life of the side channel compressor and / or the fuel cell system can be increased.

[0026] According to an advantageous method, the stator is energized without: a rotating field being formed between the stator and at least one segmented magnet, and thus the corresponding segmented magnet and thus the compressor wheel having no or very little rotational movement about the axis of rotation. In this case, when the coils of the stator are energized for a short period of time, the stator is heated, in particular due to the generated power loss, which is released as thermal energy. The thermal energy is then diffused from the stator to other components of the side channel compressor. In addition, in another possible embodiment, the stator can be energized by means of an advantageous method in such a way that inductive heating of the segmented magnets and the heating disk is achieved, in this case, in particular, a transfer of thermal energy from the heating disk to the spring element is achieved. As a result, any ice bridges that may be present melt, and the liquid changes from a solid aggregate state to a liquid aggregate state and can be discharged, for example by means of a purge valve and / or a drain valve present in the fuel cell system. As a result, the spring element can be prevented from rotating together with the inner ring of the bearing. In this way, the service life of the side channel compressor and / or the fuel cell system can be increased.

[0027] In the fuel cell system according to the invention, all the advantages that have been described for the side channel compressor according to the first aspect of the invention are produced. Therefore, compared with conventional fuel cell systems, the fuel cell system according to the invention has the following advantages: an improved arrangement of the bearing device on the bearing journal of the side channel compressor is ensured by simple means and in a cost-effective manner. By using a heating element in the region of the journal root section in the immediate vicinity of the spring element, an improved cold start capability of the side channel compressor and / or the fuel cell system can be achieved, in that it can be ensured, for example, that the spring element is prevented from rotating together with the bearing inner ring, in that it is thawed and eliminated by means of a heating disk that can be heated. In addition, the fuel cell system according to the invention has a particularly simple assembly and disassembly of the side channel compressor and can therefore be assembled cost-effectively and is very maintenance-friendly. In addition, the fuel cell system according to the invention has particularly low operating noise.

[0028] The invention is not limited to the embodiments described herein and the aspects emphasized therein. On the contrary, numerous modifications within the scope given by the description are possible which are within the capabilities of a person skilled in the art. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

[0030] The accompanying drawings show:

[0031] Figure 1 A side channel compressor according to the prior art is shown in a sectional view.

[0032] Figure 2The side channel compressor according to the prior art is shown in a cross-sectional view. Figure 1 The side channel compressor has at least one bearing and a spring element,

[0033] Figure 3 A section view shows a detail of a side channel compressor according to the invention having two bearings, a spring element and two heating disks.

[0034] Figure 4 A fuel cell system according to a preferred specific embodiment of the present invention is shown in a top view.

[0035] Components with the same function and mode of action are Figures 1 to 4 The same reference numerals are respectively provided in the figures. DETAILED DESCRIPTION

[0036] exist Figure 1 , a side channel compressor 1 according to the prior art is schematically shown in a sectional view. The side channel compressor 1 has a housing having a first housing part 3 and a second housing part 4. The first housing part 3 has a bearing journal 5 and a bearing device 9, which extends in the direction of the second housing part 4 and is arranged on the bearing journal 5, which has two rolling bearings 19, 20. In this case, the first bearing 19 and the second bearing 20b of the bearing device 9 are arranged side by side in the direction of the rotation axis R. In addition, a spacer disk 15 is located between the rolling bearings 20a, b, wherein in particular the bearing outer rings 11a, b are in axial contact with the spacer disk 15 with respect to the rotation axis R. The bearing inner ring 8 of the bearing device 9 is arranged on the bearing journal 5. The compressor wheel assembly 10 having a compressor wheel 34 is arranged on the bearing outer ring 11 of the bearing device 9. In addition, the side channel compressor 1 has a compressor chamber 36, which extends circumferentially around the rotation axis R and has at least one circumferential side channel 35.

[0037] like Figure 1 As shown, the bearing journal 5 has a blind hole in which a fastening element 28, in particular a tensioning screw 28, is arranged. The bearing 20 is at least indirectly tensioned to the first housing part 3 via the tensioning screw 28 and the spring element 18, wherein the first housing part 3 is at least indirectly tensioned to the bearing device 9 via the fastening element 28. In this case, the bearing stop disk 12 can be arranged in the direction of the rotation axis R between the fastening element 28, in particular the enlarged screw head, and the bearing journal 5 and / or the corresponding bearing inner ring 8. In addition, the bearing stop disk 12 can be at least indirectly tensioned via the spacing sleeve 14 (in Figure 3) in the direction of the axis of rotation 46 against the end face of the bearing journal 5. Now, by machining the spacer sleeve 14 before assembly, a bearing prestressing of the corresponding bearings 19, 20 can be achieved, in particular by means of a bearing prestressing force 39.

[0038] In this case, by screwing in the tensioning bolts 28, a prestressing force 39 acting parallel to the axis of rotation R is applied to the bearing device 9. It is also shown that in the direction of the axis of rotation R, there are four axial gaps 33a, b, c, d in the region between the compressor wheel assembly 10 and the respective housing parts 3, 4, wherein the axial gaps 33a, b, c, d enclose the compressor chamber 30. The bearing journal 5 has a journal root section 6 and a journal main section 7, which is connected to the inner wall 17 of the first housing part 3 (at Figure 2 ), which is directly adjacent to the journal root section 6. Two bearing inner rings 8 of two rolling bearings 20 are arranged on the journal main section 7.

[0039] In addition, Figure 1 , the drive 16 is designed as an axial field motor 16 having a stator 13, wherein a magnetic field is formed by energizing the stator 13, which acts on the segment magnets 44 of the compressor wheel assembly 10 in such a way that the compressor wheel assembly 10 is set into rotational motion. In this case, in an exemplary embodiment, the hub 37 can have a recess 45 which extends annularly around the axis of rotation R, wherein a component loop 46 and at least two segment magnets 44 (ideally, four segment magnets 44) are at least almost completely located in the recess 45.

[0040] Figure 2 The side channel compressor 1 according to the prior art is shown in a sectional view. Figure 1, the side channel compressor has at least one bearing 19, 20 and a spring element 18. It is shown here that the second bearing 20 has a bearing outer ring 11b and a bearing inner ring 8b. Here, the bearing outer ring 11b is in contact with the spacer disk 15 in the direction of the rotation axis R. Here, at least one bearing seal 42 is located between the bearing inner ring 8b and the bearing outer ring 11b in order to achieve the encapsulation of the bearing interior space, wherein in particular, the lubricating material is prevented from flowing out of the bearing interior space, but also the bearing interior space is prevented from being contaminated by particles from the outside of the corresponding bearing. Here, the bearing inner ring 8b is at least indirectly in contact with the spring element 18 in the direction of the rotation axis R. Here, the spring element 18 is supported on the contact surface 40 of the bearing inner ring 8b on one side and on the inner wall 17 of the first housing part 3 on the other side. Here, in the area of ​​the contact point of the spring element 18 with the contact surface 40 and / or the inner wall 17, the spring element 18 acts with a spring force that acts at least almost in the direction of the rotation axis R.

[0041] like Figure 2 As shown, a corresponding wear area 41 can be formed in this case, in which the spring element 18, which is made of a harder material than the friction partner, damages the friction partner 8b, 3 and can lead to material loss, especially in the corresponding wear area 41. In this case, if the bearing inner ring 8b, which should not rotate on the bearing journal 5 in normal operation, rotates at certain operating points of the side channel compressor 1, increased wear can occur. In certain operating conditions of the complete vehicle at low temperatures, especially temperatures below 0° C., such as during long parking times of the complete vehicle and subsequent cold start procedures, the spring element 18 can freeze on the corresponding bearing 19, 20, especially on the bearing inner ring 8. This freezing can occur due to ice bridges, especially at temperatures below 0° C., wherein a positive and / or non-positive connection between the bearing inner ring 8 and the spring element 18 is produced by means of the ice bridge. In this case, in the case of an unintended, rotating bearing inner ring 8, damage to the spring element 18 can occur because the spring element 18 rotates together. This can lead to damage to the spring element 18. In particular, when the spring element 18 is designed as a wave spring 18, the wave spring 18, in particular the individual windings of the wave spring 18, can be tightened, which can lead to severe damage and / or failure of the wave spring 18 and thus to severe damage and / or failure of the side channel compressor 1. In addition, the rotation can lead to considerable wear on the bearing inner ring 8b and / or on the spring element 18. Furthermore, the tightened windings can damage the bearing seal 42.

[0042] Figure 3In the sectional view, a section of a side channel compressor 1 according to the invention is shown, which has two bearings 19, 20, a spring element 18 and two heating disks 43a, b. It is shown here that a first heating disk 43a and a second heating disk 43b each extend, in particular circumferentially, around a bearing journal 5. In this case, the respective heating disk 43 is arranged in the region of the journal root section 6 and bears against the spring element 18 in the direction of the rotation axis R. In this case, the heating disk 43 can be arranged in the direction of the rotation axis R between the spring element 18 and the bearing inner ring 8 and / or between the spring element 18 and the first housing part 3, in particular in the region of the respective contact points 41a, b.

[0043] Here, the first heating disk 43a can be in contact with the spring element 18 and with the contact surface 40 of the corresponding bearing inner ring 8, in particular so that the spring element 18 does not directly contact the contact surface 40. In addition, the second heating disk 43b can be in contact with the spring element 18 and with the inner wall 17 of the first housing part 3, in particular so that the spring element 18 does not directly contact the inner wall 17. It is also shown that the spacer disk 15 is located axially with respect to the rotation axis R between the bearing outer ring 11a of the first bearing 19 and the bearing outer ring 11b of the second bearing 20.

[0044] like Figure 3 As shown, at least one heating disk 43 comprises a magnetic material, in particular a ferromagnetic material. In addition, the spring element 18 can comprise a magnetic material, in particular a ferromagnetic material. In addition, the spring element 18 can be designed as a wave spring 18. According to the invention, in addition, a method for operating a side channel compressor 1, in particular within the framework of a cold start procedure, is claimed. Within the framework of the method, an induction field, in particular an induction magnetic field, is formed by energizing the stator 13, wherein an inductive energy transfer to the corresponding heating disk 43 is thereby generated. In addition, with the method according to the invention, it is possible to energize the stator 13 without the following situation occurring: a rotating field is not formed between the stator 13 and the at least one segmented magnet 44, and thus no or very small rotational movement of the corresponding segmented magnet 44 and thus the compressor wheel 34 about the rotation axis 4 occurs. With the aid of the corresponding method according to the invention, thawing of the contact point 41 between the spring element 18 and the corresponding bearing inner ring 8 and / or between the spring element 18 and the first housing part 3 can be ensured, wherein, in addition, with the aid of heating of the corresponding heating plate 43, acceleration of the cold start procedure of the side channel compressor 1 and / or the fuel cell system 2 can be ensured.

[0045] exist Figure 4Schematically, a fuel cell system 2 according to a preferred embodiment of the present invention is shown in a top view. The fuel cell system 2 has a fuel cell 21, which has an anode 25 and a cathode 26, which are surrounded by an electrolyte 27. A membrane 29 is arranged between the anode 25 and the cathode 26. Adjacent to the anode 25, the fuel cell 21 has a hydrogen inlet 23 for supplying hydrogen. Adjacent to the cathode 26, the fuel cell 21 has an oxygen inlet 22 for supplying oxygen or an oxygen-containing gas mixture and an exhaust gas outlet 24 for conducting exhaust gas from the fuel cell 21, the oxygen-containing gas mixture being, for example, filtered air. A water separator 30 for separating water and a side channel compressor 1 according to the present invention are arranged at the exhaust gas outlet 24.

[0046] In addition, the working chamber inlet 31 of the side channel compressor 1 is coupled to the exhaust gas outlet 24 in fluid communication, so that the exhaust gas can be supplied from the exhaust gas outlet 24 to the working chamber of the side channel compressor 1 via the working chamber inlet 31 for compression. The working chamber outlet 32 ​​of the side channel compressor 1 is coupled to the hydrogen inlet 23 in fluid communication, so that the hydrogen can be supplied from the working chamber to the fuel cell 21 again via the working chamber outlet 32 ​​and the hydrogen inlet 23.

Claims

1. A side channel compressor (1) for a fuel cell system (2), the side channel compressor being used for compressing a gaseous medium, the side channel compressor having a housing, the housing having a first housing part (3) and a second housing part (4), wherein: The first housing part (3) has a bearing journal (5) extending along the rotation axis R, the bearing journal having a journal root section (6) and a journal main section (7), wherein at least one bearing inner ring (8) of a bearing device (9) is arranged on the journal main section (7), wherein a compressor wheel assembly (10) having a compressor wheel (34) is arranged in the housing on at least one bearing outer ring (11) of the bearing device (9) in a manner rotatable about the rotation axis R and can be driven by means of a drive (16) , wherein the first housing part (3) is at least indirectly tensioned to the bearing device (9) via a fastening element (28), and wherein, in particular in the direction of the rotation axis R, a spring element (18) is arranged between the bearing device (9) and the first housing part (3), characterized in that at least one heating disk (43) is arranged in the area of ​​the journal root section (6) and abuts against the spring element (18) in the direction of the rotation axis R, the heating disk in particular extending circumferentially around the bearing journal (5).

2. The side channel compressor (1) according to claim 1, characterized in that The heating disk (43) is arranged in the direction of the rotation axis R between the spring element (18) and the bearing inner ring (8) and / or between the spring element (18) and the first housing part (3), in particular in the region of corresponding contact points (41a, b).

3. The side channel compressor (1) according to claim 1 or 2, characterized in that: The heating disk (43) bears against the spring element (18) and against a contact surface (40) of a corresponding bearing inner ring (8), in particular so that the spring element (18) does not bear directly against the contact surface (40).

4. The side channel compressor (1) according to claim 1 or 2, characterized in that The heating disk (43) bears against the spring element (18) and against the inner wall (17) of the first housing part (3), in particular so that the spring element (18) does not bear directly against the inner wall (17).

5. A side channel compressor (1) according to any one of the preceding claims, characterised in that The at least one heating disk (43) comprises a magnetic material, in particular a ferromagnetic material.

6. A side channel compressor (1) according to any one of the preceding claims, characterised in that The spring element (18) comprises a magnetic material, in particular a ferromagnetic material.

7. A side channel compressor (1) according to any one of the preceding claims, characterised in that The spring element (18) is designed as a wave spring (18).

8. A method for operating a side channel compressor (1) according to any one of the preceding claims, in particular within the framework of a cold start procedure, characterized in that By energizing the stator (13), an induction field, in particular an induction magnetic field, is formed, wherein an inductive energy transmission to the corresponding heating disk (43) is thereby generated.

9. The method according to claim 8, characterized in that The stator (13) is energized without a rotating field being built up between the stator (13) and at least one segmented magnet (44), and thus the corresponding segmented magnet (44) and thus the compressor wheel (34) undergoing no or very little rotational movement about the rotation axis (4).

10. A fuel cell system (2), comprising a fuel cell (21), wherein the fuel cell has an oxygen inlet (22), a hydrogen inlet (23), an exhaust gas outlet (24), an anode (25), a cathode (26) and an electrolyte (27), It is characterized in that The fuel cell system (2) has a side channel compressor (1) according to any one of the preceding claims, which is coupled in a fluidic manner to the exhaust gas outlet (24).

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