Side-channel compressor for a fuel cell system for conveying and / or compressing a gaseous medium, and fuel cell system

Abstract

The invention relates to a side-channel compressor (1) for a fuel cell system (2) for compressing a gaseous medium, having a housing with a first housing part (3) and a second housing part (4). The first housing part (3) has a bearing journal (5) extending along a rotational axis (R); a bearing inner ring (8) of a bearing device (9) is provided on the bearing journal (5); the bearing device (9) comprises a first bearing (19) and a second bearing (20); each bearing (19, 20) has two sealing discs (21) which encapsulate the bearing interior (27); and a compressor wheel assembly (10) having a compressor wheel (34) is provided within the housing so as to be rotatable about the rotational axis (R) on a bearing outer ring (11) of the bearing device (9). According to the invention, a respective first and / or second outer diameter (D1, D2) of each water-deflecting disc (23, 41) is at least equal to and / or greater than a third outer diameter (D3) of a respective bearing outer ring (11a, b) and / or a first inner diameter (D5) of a hub (16). The invention also relates to a fuel cell system (2) comprising a side-channel compressor (1) according to the invention.

Description

[0001] Description

[0002] title

[0003] Side channel compressor for a fuel cell system for conveying and / or compressing a gaseous medium, fuel cell system

[0004] The present invention relates to a side channel compressor for a fuel cell system for conveying and / or compressing a gaseous medium, in particular hydrogen, which is intended in particular for use in vehicles with a fuel cell drive. Furthermore, the invention relates to a fuel cell system with a side channel compressor according to the invention.

[0005] In the automotive sector, gaseous fuels will play an increasingly important role alongside liquid fuels in the future. Particularly in vehicles with fuel cell propulsion, hydrogen gas flows must be controlled. Unlike liquid fuel injection, where gas flows are controlled discontinuously, the gaseous medium is drawn from at least one high-pressure tank and fed via a supply line of a medium-pressure line system to an ejector unit. This ejector unit then directs the gaseous medium via a connecting line of a low-pressure line system to a fuel cell. After the gaseous medium has flowed through the fuel cell, it is returned to the ejector unit via a return line. A side-channel compressor can be integrated into this process.which supports gas recirculation in terms of flow and efficiency. Side channel compressors are also used to support flow build-up in fuel cell drives, particularly during a (cold) start of the vehicle after a certain period of inactivity. These side channel compressors are typically driven by electric motors, which, when operating in vehicles, are supplied with voltage via the vehicle battery. From the unpublished DE 10 2023 212 524, a side channel compressor for a fuel cell system for conveying and / or compressing a gaseous medium, in particular hydrogen, is described, comprising a housing with a first housing part and a second housing part, wherein the first housing part has a bearing journal extending along an axis of rotation R, wherein a bearing inner ring of a bearing device is arranged on the bearing journal, and wherein the bearing device has a first bearing and a second bearing.wherein each bearing has two sealing discs that encapsulate the bearing interior, wherein a compressor wheel assembly with a compressor wheel is rotatably arranged inside the housing on a bearing outer ring of the bearing device about the axis of rotation R and is driveable via a drive, wherein the first housing part is clamped at least indirectly to the bearing device via a fastening screw. According to the invention, the side channel compressor and / or the compressor wheel assembly has a first water deflector disc and / or a second water deflector disc.

[0006] The side-channel blower known from DE 10 2023 212 524 can have certain disadvantages. Water can accumulate in the area of ​​a water ingress gap, which runs circumferentially around the axis of rotation R and forms between the respective water deflector disc and an end face, in particular the respective sealing disc, of the respective bearing. The water entering this water ingress gap can lead to oxidation of the bearings and the water deflector discs, which can result in component or bearing failure.When operating a side-channel blower according to the state of the art, there is only a reduced risk of water ingress and / or remaining in the water ingress gap. This is because the high rotational speed of the bearings, and thus of the respective sealing disc, throws any water accumulating in the water ingress gap outwards, preventing it from reaching the sealing point between the sealing disc and the inner bearing ring. However, when the side-channel blower is switched off, the risk is increased that the water, which remains permanently in the respective water ingress gap, will eventually penetrate into the bearing interior, particularly through the ingress path between the sealing disc and the inner bearing ring, and damage a rolling element of the bearing. This leads to a shortened service life of the respective bearing and ultimately of the entire side-channel blower.Furthermore, water that is present in and / or has penetrated the water ingress gap can form ice bridges and freeze, especially during extended periods of vehicle inactivity at sub-zero temperatures. This freezing water can then expand and damage the compressor wheel assembly by forcing the water deflector disc out of the assembly. This damage to the compressor wheel assembly increases the likelihood of failure of the entire side-channel compressor.

[0007] Disclosure of the invention

[0008] The present invention relates to a side-channel compressor for a fuel cell system for compressing a fluid, comprising the features of independent claim 1, and to a fuel cell system comprising a side-channel compressor comprising the features of dependent claim 10. Further features and details of the invention will become apparent from the dependent claims, the description, and the drawings. Features and details described in connection with the side-channel compressor according to the invention naturally also apply in connection with the fuel cell system according to the invention, and vice versa, so that the disclosure relating to the individual aspects of the invention always refers, or can refer, to each other.

[0009] According to a first aspect of the invention, a side-channel compressor for a fuel cell system is provided for compressing a gaseous medium. The side-channel compressor has a housing with a first housing part and a second housing part, the first housing part having a bearing journal extending along an axis of rotation R. An inner bearing ring of a bearing assembly is arranged on the main section of the journal. The bearing assembly has a first bearing and a second bearing, each bearing having two sealing discs that fluidically encapsulate the bearing interior. A compressor wheel assembly with a compressor wheel is rotatably arranged inside the housing on an outer bearing ring of the bearing assembly about the axis of rotation R and can be driven by a drive. The first housing part is at least indirectly clamped to the bearing assembly by means of a fastening screw.

[0010] According to the invention, it may be provided, but is not absolutely necessary, that the first housing part and / or the second housing part comprise further housing parts, which may in particular be designed as a housing cover, housing wall, or the like. Preferably, the first housing part defines a pre-assembled assembly of the side channel blower, which includes the bearing device and the compressor wheel assembly. The housing, preferably through the interaction of the first housing part with the second housing part, forms a working space for the compressor wheel assembly.

[0011] The working chamber is preferably designed to be fluid-tight, apart from a working chamber inlet and a working chamber outlet. Within the scope of the invention, "fluid-tight" also means that the tightness is maintained even at a higher operating pressure of the silk channel compressor than the ambient pressure. To ensure tightness, sealing devices, such as sealing rings, in particular elastomers made of EPDM and FKM, or the like, are preferably provided between the first housing part and the second housing part. The first housing part is preferably made essentially or predominantly of aluminum. The second housing part is preferably made essentially or predominantly of aluminum.

[0012] The bearing journal is formed as a section of the first housing part and extends from an inner wall of the first housing part. According to the invention, the bearing journal is formed monolithically with the first housing part. Alternatively, the bearing journal can also be attached to the first housing part by a material bond, for example by welding, or by a force bond, for example by bolting or pressing. The bearing journal extends from the inner wall of the first housing part from the journal root section, through the main journal section, to the journal end section. The journal end section includes the journal clamping section. Preferably, the journal end section is designed as a journal clamping section.

[0013] The bearing assembly comprises an inner bearing ring and an outer bearing ring. Preferably, several rolling elements, such as balls, rollers, barrels, or the like, are arranged between the inner and outer bearing rings to support the outer bearing ring on the inner bearing ring with minimal play and to ensure relative rotation between the inner and outer bearing rings.

[0014] The inner bearing ring of the bearing assembly is arranged on the main journal section, preferably in a loose fit. Several inner bearing rings can also be arranged on the main journal section, preferably each in a loose fit. The loose fit is preferably designed such that, when the clamping force is released, the bearing assembly can be easily moved on the journal, for example manually, and tilting of the inner bearing ring on the journal is prevented.

[0015] The compressor wheel assembly is arranged on the outer bearing ring of the bearing assembly, preferably in an interference fit. The interference fit is preferably designed such that displacement of the compressor wheel assembly on the bearing assembly is prevented by frictional engagement. Alternatively, the compressor wheel assembly can be arranged on the outer bearing ring in a loose fit and secured against axial slippage from the bearing assembly by retaining means.

[0016] With reference to claim 1, the side channel blower is designed such that the respective first and / or second outer diameter D1, D2 of a respective water deflector disc is at least equal to and / or larger than the third outer diameter D3 of a respective bearing outer ring and / or the first inner diameter D5 of a hub. This provides the advantage of improved encapsulation of the blower wheel assembly, as the respective water deflector disc can extend further around the respective bearings and / or the hub, thus providing better encapsulation. The increased diameter of the respective water deflector disc compared to the respective bearing outer ring and / or the hub allows for improved encapsulation of the bearing interior and / or the inner area of ​​the blower wheel assembly, thereby increasing the service life of the side channel blower.Furthermore, the probability of failure of the respective bearing due to water ingress can be reduced. Advantageous further developments of the side channel blower specified in claim 1 are possible through the measures listed in the dependent claims. The dependent claims relate to preferred further developments of the invention.

[0017] According to a particularly advantageous embodiment of the side-channel blower, the first water-deflecting disc and / or a second water-deflecting disc is arranged in the direction of the axis of rotation R on a sixth end face of the hub and / or a seventh end face of the second bearing, in particular with a respective end face, such that a first and / or second water penetration gap is formed. In this way, the advantage can be achieved that a respective additional water penetration gap is formed between the first water-deflecting disc and the hub and / or between the second water-deflecting disc and the outer bearing ring of the second bearing.This allows an additional encapsulating barrier to be formed between the environment and the bearing interior and / or the inner area of ​​the compressor wheel assembly, so that improved encapsulation of the bearings and the compressor wheel assembly against water and / or liquids penetrating from the environment can be achieved, thereby increasing the service life of the bearings and thus of the entire side channel blower.

[0018] According to a particularly advantageous embodiment of the side-channel compressor, the compressor wheel assembly has at least one water deflector disc, wherein the at least one water deflector disc has at least one annular collecting groove on its side facing the respective bearing, in particular on its end face. This achieves the advantage that water penetrating the area between the water deflector disc and the respective bearing and / or the respective sealing disc can be drained and / or collected in the respective groove. Water accumulating in a water ingress gap is thereby drained into the respective groove. Furthermore, the respective collecting groove interrupts the capillary action of the water ingress gap, by which water is drawn into the gap and thus transported to the respective bearing when the compressor wheel is stationary.Thus, the respective bearing is protected from water ingress even when the compressor wheel is stationary. Water is drawn from the water ingress gap only as far as the collecting groove and not to the inner ring, preventing it from penetrating the bearing. According to an advantageous embodiment of the side-channel compressor, a first water deflector disc has a first shoulder, wherein the first water deflector disc forms a first end face and a third end face on its side facing the second bearing, the end faces being set off and / or separable by the first shoulder. This offers the advantage of simplified installation of the respective water deflector disc in or on the compressor wheel assembly, thereby reducing assembly costs.Furthermore, the respective water deflector disc can be arranged in and / or on the compressor wheel assembly in a space-saving manner, resulting in a compact design of the compressor wheel assembly and thus reducing the overall size of the side channel blower. This, in turn, can reduce the installation space required for the side channel blower within the vehicle.

[0019] According to an advantageous embodiment of the side-channel blower, the first water-deflecting disc and / or the second water-deflecting disc is arranged in the direction of the axis of rotation R on a respective end face of a hub and / or the respective bearing and / or the respective sealing disc, in particular with a respective end face, such that the respective water penetration gap is formed. In this way, a compact design of the blower wheel assembly and / or the side-channel blower can be achieved. Furthermore, at least partial fluidic encapsulation of a respective bearing interior and / or the inner area of ​​the blower wheel assembly can be achieved by forming the respective water penetration gap through which water and / or other liquids from the environment cannot pass, or can only pass through with difficulty, due to their surface tension.This can increase the service life of the respective bearing and thus of the entire side channel blower.

[0020] According to an advantageous embodiment of the side-channel compressor, each water ingress gap has a gap dimension of less than 1 mm. This increases the effectiveness of the water ingress gap to such an extent that water penetrating from the surrounding environment cannot pass through it, thus creating an encapsulating effect. This prevents the water from penetrating into the inner area of ​​the compressor wheel assembly and the bearing interior, since the gap dimension of each water ingress gap is so small that the water and / or liquid cannot penetrate it due to the existing surface tension.This prevents water from penetrating the water ingress gap, particularly when the side channel blower is at rest. This, in turn, prevents damage to the bearings from water ingress. Furthermore, it reduces the risk of water wetting the surface of the water deflector disc, especially the surface facing the bearing, and utilizes an inhomogeneous capillary effect. This extends the service life of the bearings, water deflector discs, and surrounding components. Consequently, the failure probability of the entire side channel blower is reduced, and its service life is extended.

[0021] According to an advantageous embodiment of the side-channel blower, a first annular collecting groove is formed in the area of ​​the first end face of the first water deflector disc, wherein a fourth outer diameter D4 of the first annular collecting groove corresponds at least approximately to a first inner diameter D5 of a hub. This achieves the advantage of collecting water that enters the side-channel blower during operation, particularly after passing through a first water ingress gap, which is located especially in the area between the end face of the hub and the first end face. The water can be collected directly in the first collecting groove and / or discharged into it. Furthermore, when the side-channel blower transitions from standstill to operation, the water is transported out of the blower wheel assembly by centrifugal forces.Furthermore, the advantage is that the existing first collecting groove interrupts the capillary action of the first water ingress gap, thus preventing water from being drawn through the respective water ingress gap by capillary action and transported to the bearing when the side-channel blower is stationary. This protects the bearing from water ingress even when the impeller is stationary, thereby reducing the probability of bearing failure and increasing the service life of the side-channel blower. According to a particularly advantageous embodiment of the side-channel blower, a fifth outer diameter D6 of a second annular collecting groove corresponds at least approximately to a sixth inner diameter D8 of the respective bearing.This design offers the advantage of collecting any water that enters the side-channel blower during operation, particularly after it has passed through a second water ingress gap. This gap is located specifically between the end face of the hub and a second end face of a second water deflector disc. The water can then be collected directly in the second collection groove and / or discharged into it. Furthermore, when the side-channel blower transitions from standstill to operation, centrifugal forces expel the water from the impeller assembly.Furthermore, the advantage is that the second collecting groove interrupts the capillary action of the second water ingress gap, thus preventing water from being drawn through the respective water ingress gap by capillary action and transported to the bearing when the side channel blower is stationary. This protects the bearing from water ingress even when the impeller is stationary, thereby reducing the probability of bearing failure and extending the service life of the side channel blower.

[0022] According to a particularly advantageous embodiment of the side-channel blower, the sealing discs located at the respective water ingress gap form several flow wedges on their end face facing the water ingress gap, running at least approximately perpendicular to the axis of rotation R. This achieves the advantage that, during operation of the side-channel blower, in which the sealing disc rotates with a bearing outer ring, the flow wedges perform a rotational movement around the axis of rotation along with the sealing disc. The water in the area of ​​the respective water ingress gap is thereby set into a rotational movement around the axis of rotation by the rotating wedges. This generates centrifugal forces on the medium, directed away from the axis of rotation and / or the bearing inner ring. Thus, the drainage of the water in the respective water ingress gap via the respective axial groove is further supported and accelerated.This allows water to be drained away from the compressor wheel assembly. This prevents damage to the bearing and reduces the probability of bearing failure due to water damage. Therefore, the failure rate of the side channel blower can be reduced and / or the service life of the bearing and / or the side channel blower can be increased.

[0023] According to an advantageous embodiment of the side-channel compressor, a spring element is arranged at least indirectly between the first water deflector disc and the first housing part in the direction of the axis of rotation R. This achieves the advantage of cost reduction. A wave spring is readily available at low cost and exhibits a characteristic curve advantageous for this application. This has the advantage that a reliable and constant supply of the clamping force and / or bearing preload is ensured by means of the wave spring in a simple and cost-effective manner.

[0024] The fuel cell system according to the invention offers all the advantages already described for a side-channel blower according to the first aspect of the invention. Accordingly, the fuel cell system according to the invention has the advantage over conventional fuel cell systems that improved encapsulation of the bearings, in particular of the respective bearing interior, can be achieved with simple means. In this way, the stress and damage to the respective bearings and / or the bearing assembly caused by water ingress can be reduced, and the service life of the bearing assembly can thus be significantly extended compared to conventional side-channel blowers. Furthermore, the fuel cell system according to the invention features particularly easy assembly and disassembly of the side-channel blower and is therefore cost-effective to install and very easy to maintain.

[0025] The invention is not limited to the embodiments described here and the aspects highlighted therein. Rather, within the scope specified by the claims, a multitude of modifications are possible that fall within the bounds of what is considered skilled in the art.

[0026] Brief description of the drawing: The invention is described in more detail below with reference to the drawing.

[0027] It shows:

[0028] Figure 1 shows a sectional view of a side channel blower according to the prior art.

[0029] Figure 2 shows a sectional view of a section of the side channel compressor according to the invention, designated II in Fig. 1, with a compressor wheel assembly.

[0030] Figure 3 shows a sectional view of a section of the side channel compressor according to the invention, designated III in Fig. 2, with a compressor wheel assembly according to the invention.

[0031] Elements with the same function and mode of operation are each provided with the same reference symbols in Figures 1 to 3.

[0032] Figure 1 shows a schematic sectional view of a side-channel blower 1 according to the prior art. The side-channel blower 1 has a housing with a first housing part 3 and a second housing part 4. The first housing part 3 has a bearing journal 5 extending towards the second housing part 4 and a bearing assembly 9 arranged on the bearing journal 5 with two rolling bearings 19, 20. A first bearing 19 and a second bearing 20 of the bearing assembly 9 are arranged side by side in the direction of an axis of rotation R. A spacer 15 is located between the rolling bearings 19, 20, with each bearing outer ring 11a, b being in axial contact with the spacer 15 along the axis of rotation R. Inner bearing rings 8 of the bearing assembly 9 are arranged on the bearing journal 5. A hub 16 with a compressor wheel 34 is arranged on the outer bearing rings 11a, b of the bearing device 9.Furthermore, the side-channel compressor 1 has a compressor chamber 36 extending around the axis of rotation R, which has at least one circumferential side channel 35. As shown in Fig. 1, the bearing journal 5 has a recess with an internal thread in which a fastening screw 28 is arranged. The bearings 19, 20 are at least indirectly clamped to the first housing part 3 and a bearing washer 12 via the fastening screw 28, wherein the first housing part 3 is at least indirectly clamped to the bearing assembly 9 via the fastening screw 28. In an exemplary embodiment, a spring element 14 can also be located between the housing and a compressor wheel assembly 10, which is additionally clamped by means of the fastening screw 28.A stop washer 12 can be arranged in the direction of the axis of rotation R between the fastening screw 28, in particular an enlarged screw head, and the bearing journal 5 and / or the respective inner bearing ring 8. The compressor wheel 34 is arranged to rotate about the axis of rotation R in the housing and can be driven by a drive 37. The first housing part 3 is clamped to the bearing assembly 9, at least indirectly, via the fastening screw 28.

[0033] Furthermore, Fig. 1 shows that by screwing in the fastening screw 28, a preload force 39 acting parallel to the axis of rotation R is applied to the bearing device 9. It is also shown that four axial gaps 33a, b, c, d are located in the direction of the axis of rotation R in the area between the compressor wheel assembly 10 and the respective housing part 3, 4, wherein the axial gaps 33a, b, c, d enclose the compressor chamber 36. The compressed gaseous medium can then be conveyed from the compressor chamber 36 of the side channel compressor 1 to a fuel cell 26 of a fuel cell system 2. The side channel compressor 1 can be arranged in an anode circuit of the fuel cell system 2.The drive 37 can be designed as an axial field electric motor 37, which has a stator 37, wherein a magnetic field is formed by means of an energizing the stator 37, which acts on a segment magnet of the compressor wheel assembly 10 in such a way that the compressor wheel assembly 10 is set into a rotary motion.

[0034] Fig. 2 shows a sectional view of a section of the side channel compressor 1 according to the invention, labelled II in Fig. 1, with the compressor wheel assembly 10. It is shown that the first bearing 19 has the outer bearing ring 11a and the inner bearing ring 8a, while the second bearing 20 has the outer bearing ring 11b and the inner bearing ring 8b. At least one sealing washer 21 is located between the respective inner bearing ring 8a, b and the respective outer bearing ring 11a, b to encapsulate a bearing interior 27, thereby preventing, in particular, the escape of lubricant from the bearing interior 27 and also preventing contamination of the bearing interior 27 by particles from outside the respective bearing 19, 20, especially from an environment 29.The respective sealing disc 21 is connected to the respective bearing outer ring 11 a, b by a force-fit, positive-fit, and / or friction-fit connection, wherein the respective sealing disc 21 rotates with the respective bearing outer ring 11 a, b during operation of the side channel blower 1. The side channel blower 1 has a housing with the first housing part 3 and the second housing part 4, wherein the first housing part 3 has the bearing journal 5 extending along the axis of rotation R, and wherein at least one bearing inner ring 8 of the bearing assembly 9 is arranged on the bearing journal 5. The bearing assembly 9 has the first bearing 19 and the second bearing 20, wherein each bearing 19, 20 has, for example, two sealing discs 21, but has at least one sealing disc 21 that encapsulates the bearing channel space 27. According to the invention, the compressor wheel assembly 10 has at least one water deflector disc 23, 41.

[0035] Furthermore, Fig. 2 shows that at least one sealing element 42 is arranged orthogonally to the axis of rotation R between the bearing journal 5 and at least one inner bearing ring 8a, 8b, wherein the sealing element 42 is arranged in a cup-shaped recess 7 on an outer diameter 47 of the bearing journal 5. This sealing element 42 can, in particular, be an O-ring 42. This at least one sealing element 42 provides additional encapsulation of the respective bearing interior 27 against liquids, in particular against water, which could penetrate between the bearing journal 5 and the respective inner bearing ring 8a, b into the area between the two bearings 19, 20. The respective sealing element 42 thus prevents the penetration of water.

[0036] Fig. 3 shows a sectional view of a section of the side-channel compressor 1 according to the invention, designated III in Fig. 2, with a compressor wheel assembly 10 according to the invention. The side-channel compressor 1 has a first and a second bearing 19, 20 with the respective bearing outer ring 11 a, b and the respective bearing inner ring 8a, b. It is shown that the compressor wheel assembly 10 has at least one water deflector disc 23, 41, wherein the at least one water deflector disc 23, 41 has at least one annular collecting groove 25, 45 on at least its side facing the respective bearing 19, 20, in particular on a respective end face 30, 32. It is also shown that the first water deflector disc 23 has a first outer diameter D1 and the second water deflector disc 41 has a second outer diameter D2.Furthermore, the respective outer bearing ring 11 a, b of the respective bearing 19, 20 has a third outer diameter D3. The hub 16 also has a first inner diameter D5. In the side channel compressor 1 according to the invention, the respective first and / or second outer diameter D1, D2 of the respective water deflector disc 23, 41 is at least equal to and / or larger than the third outer diameter D3 of the respective outer bearing ring 11 a, b and / or the first inner diameter D5 of the hub 16.

[0037] This inventive design of the respective water-deflecting disc 23, 41 makes it possible for the first water-deflecting disc 23 and / or a second water-deflecting disc 41 to be arranged in the direction of the axis of rotation R on a sixth end face 49 of the hub 16 and / or a seventh end face 50 of the second bearing 19, in particular with a respective end face 30, 32, so that a first and / or second water ingress gap 43a, b is formed. This respective water ingress gap 43a, b serves as a further barrier against water penetrating from the environment 29 into the compressor wheel assembly 10 and / or the bearings 19, 20 and / or the bearing interior 27.Furthermore, the first water-deflecting disc 23 has a first shoulder 46, wherein the first water-deflecting disc 23 forms a first end face 30 and a third end face 38 on its side facing the second bearing 20, and wherein the end faces 30, 38 are set off and / or separable by the first shoulder 46. The second water-deflecting disc 41 has a second end face 32, and the sealing disc 21 of the second bearing 20 facing the first water-deflecting disc 23 has a fourth end face 40, and the sealing disc 21 of the first bearing 19 facing the second water-deflecting disc 41 has a fifth end face 44. Fig.Figure 3 further shows that the first water-deflecting disc 23 and / or the second water-deflecting disc 41 is arranged in the direction of the axis of rotation R on a respective end face of the hub 16 and / or the respective bearing 19, 20 and / or the respective sealing disc 21, in particular with the respective end face 30, 32, 38, so that a respective water ingress gap 43a, b, c, d is formed. The respective water ingress gap 43a, b, c, d has a gap dimension of less than 1 mm, thereby achieving good protection against water ingress. Furthermore, a first annular collecting groove 25 in the area of ​​the first end face 30 of the first water deflector disc 23 is designed such that a fourth outer diameter D4 of the first annular collecting groove 25 corresponds at least approximately to a first inner diameter D5 of the hub 16.The hub 16 also forms a second inner diameter D7, wherein the bearings 19, 20 are pressed into the hub 16 in the area D7 and / or the respective bearing 19, 20, in particular the respective bearing outer ring 11 a, b, also forms a respective second shoulder 48a, b, wherein the respective bearing outer ring 11 a, b forms a sixth inner diameter D8 in the area of ​​the respective shoulder 48a, b, wherein the respective sealing washer 21 is located in the area of ​​the shoulder 48a, b and is pressed into it. Furthermore, a fifth outer diameter D6 of a second annular collecting groove 45 corresponds at least almost to a sixth inner diameter D8 of the respective bearing 19, 20. In this respect, the respective groove 25, 45 interrupts the capillary action of the respective gap 43 and thus further improves the protective effect against water penetrating into the respective water ingress gap 43a, b, c, d.Furthermore, the sealing discs 21 located at the respective water ingress gap 43 can form several flow wedges on their end face facing the water ingress gap 43, which run at least approximately orthogonally to the axis of rotation R. This results in a rotationally symmetrical acceleration in a side-channel compressor in operation and with the respective sealing disc 21 in rotation, which also sets the water located between the flow wedges into rotation. Due to the centrifugal forces that occur, the water can now be moved outwards away from the axis of rotation R and out of the respective water ingress gap 43, and thus, in particular, discharged into the surroundings 29. As shown in Fig.Figure 3 further shows that the spring element 14 is arranged at least indirectly between the first water deflector disc 23 and the first housing part 3 in the direction of the axis of rotation R. The spring element 14 allows the compressor wheel assembly 10 and / or the bearing assembly 9 to be subjected to a clamping force and / or bearing preload in the direction of the axis of rotation R. The spring element 14 can be designed as a wave spring 14. It is also shown that each bearing 19, 20 has at least one rolling element 18. The side channel compressor 1 described above can be used, in particular, in the fuel cell system 2.

Claims

Claims 1. Side channel compressor (1) for a fuel cell system (2) for compressing a gaseous medium, comprising a housing with a first housing part (3) and a second housing part (4), wherein the first housing part (3) has a bearing journal (5) extending along an axis of rotation (R), wherein at least one inner bearing ring (8) of a bearing device (9) is arranged on the bearing journal (5), wherein the bearing device (9) has at least one bearing (19, 20), wherein the at least one bearing (19, 20) each has at least one sealing disc (21) that encapsulates the bearing channel space (27), wherein a compressor wheel assembly (10) with a compressor wheel (34) is rotatably arranged inside the housing on a bearing outer ring (11) of the bearing device (9) about the axis of rotation (R) and can be driven by a drive (37), characterized in that a respective first and / or second outer diameter (D1,D2) of a respective water deflector disc (23, 41) is at least equal in size and / or larger than a third outer diameter (D3) of a respective bearing outer ring (11 a, b) and / or a first inner diameter (D5) of a hub (16)., 2. Side channel compressor (1) according to claim 1, characterized in that the first water deflector disc (23) and / or a second water deflector disc (41) is arranged in the direction of the axis of rotation (R) on a sixth end face (49) of the hub (16) and / or a seventh end face (50) of the second bearing (19), in particular with a respective end face (30, 32), so that a first and / or second water penetration gap (43a, b) is formed.

3. Side channel blower (1) according to one of the preceding claims, characterized in that the respective water deflector disc (23, 41) has at least one annular collecting groove (25, 45) on its side facing the respective bearing (19, 20), in particular on the respective end face (30, 32).

4. Side channel blower (1) according to one of the preceding claims, characterized in that the first water deflector disc (23) has a first shoulder (46), wherein the first water deflector disc (23) forms the first end face (30) and a third end face (38) on its side facing the second bearing (20), wherein the end faces (30, 38) are set off and / or separable by the first shoulder (46).

5. Side channel compressor (1) according to one of the preceding claims, characterized in that the respective water ingress gap (43a, b, c, d) has a gap dimension of less than 1 mm.

6. Side channel compressor (1) according to one of the preceding claims, characterized in that the first annular collecting groove (25) is formed in the area of ​​the first end face (30) of the first water deflector disc (23), wherein a fourth outer diameter (D4) of the first annular collecting groove (25) corresponds at least nearly to a first inner diameter (D5) of the hub (16).

7. Side channel compressor (1) according to one of the preceding claims, characterized in that a fifth outer diameter (D6) of the second annular collecting groove (45) corresponds at least approximately to a sixth inner diameter (D8) of the respective bearing (19, 20) 8. Side channel compressor (1) according to one of the preceding claims, characterized in that the sealing discs (21) located at the respective water inlet gap (43) form several flow wedges on their end face facing the water inlet gap (43) which extend at least approximately orthogonally to the axis of rotation (R).

9. Side channel compressor (1) according to one of the preceding claims, characterized in that a spring element (14) is arranged at least indirectly between the first water deflector disc (23) and the first housing part (3) in the direction of the axis of rotation (R).

10. Fuel cell system (2) with a side channel compressor (1) according to one of claims 1 to 9, wherein the side channel compressor (1) is arranged in an anode circuit of the fuel cell system (2).

Images