Humidifier

Abstract

The invention relates to a humidifier for humidifying a dry first gas stream by means of a humid second gas stream, in particular for a fuel cell system, comprising a housing made of plastic, which has a recess in the housing bottom, in which recess there is a recess cavity for collecting water produced in the housing, wherein there is a discharge opening in the recess cavity, wherein there is a water outlet on the housing externally for conducting water out, which is in fluid connection with the discharge opening. A compact and low-cost construction is possible if the humidifier has a tube made of metal, which forms the discharge opening at one end, the water outlet at the other end and fluidically connects the discharge opening with the water outlet, and if the humidifier has an electric heating device, which is directly or indirectly in heat transfer connection with the tube.

Description

Technical Field

[0001] The present invention relates to a humidifier for humidifying and drying a first gas stream by means of a moist second gas stream, as described in the preamble of claim 1, the humidifier being particularly suitable for fuel cell systems. Background Technology

[0002] This type of humidifier is particularly useful in fuel cell systems, where a humidified cathode exhausts air to humidify a dry cathode intake. However, in principle, it can also be considered for any other applications of this type. For example, within the framework of building air conditioning, a humidified building exhaust can be used to humidify a dry building intake. The corresponding application applies to air-conditioned spaces and air-conditioning boxes where a constant humidity level with air exchange is required. In the current context, humidity is water, which can appear in liquid, gaseous, droplet, or vapor form—that is, both gaseous and droplet forms. Water can be generated in humidifiers, especially through condensation, and accumulates in the housing, potentially freezing at correspondingly low ambient temperatures. This can impair the humidifier's functional efficiency.

[0003] Humidifiers according to this category are known by DE 10 2021 204 250 A1 and have a housing made of plastic with a recess in the bottom of the housing containing a cavity for collecting water generated in the housing. Additionally, a drain opening is present in the cavity, and an outlet is located on the outside of the housing for draining water, the outlet being in fluid connection with the drain opening. In this way, water collected in the housing or cavity can be drained from the housing through the drain opening and the outlet. In known humidifiers, a heating channel is provided in the area of ​​the cavity at the bottom of the housing, through which a heating medium can flow. This prevents water accumulated in the housing or cavity from freezing. Similarly, frozen water in the area of ​​the cavity can be thawed by means of the heating channel. The heating channel has a heating medium inlet for supplying the heating medium and a heating medium outlet for draining the heating medium on the bottom of the housing, and is therefore relatively laboriously designed and constructed to be relatively large. Summary of the Invention

[0004] The present invention addresses the problem of providing an improved or at least different implementation of the humidifier of the type mentioned above, the outstanding feature of which is, in particular, reduced cost, while striving to achieve a compact structural form.

[0005] According to the present invention, this problem is solved by the subject matter of the independent claims. Advantageous embodiments are the subject matter of the dependent claims.

[0006] This invention is based on the following general concept: equipping a humidifier with an electric heating device and a metal fitting, which is connected to the heating device via heat transfer, and connecting the discharge opening to the water outlet. The electric heating device requires little installation space and can be implemented relatively simply. By using a metal fitting that can be heated by the heating device, the transfer of heat to the water is simplified. Therefore, the electric heating device operates particularly efficiently when combined with the fitting.

[0007] Specifically, the humidifier includes a metal tubing with a discharge opening at one end and a water outlet at the other, which are in fluid connection. Furthermore, the humidifier according to the invention includes an electric heating device connected directly or indirectly to the tubing via heat transfer. The tubing typically has two ends, and according to the invention, one end forms the discharge opening, while the other forms the water outlet. Therefore, the heat input to the tubing, achievable by the heating device, directly reaches the discharge opening and the water outlet, extending from the discharge opening to the water outlet within the tubing. This protects a crucial component of the water discharge from the housing from icing or allows for easy defrosting of that component.

[0008] In the current context, “configuration” is synonymous with “structure” and / or “establishment”, making the expression “configured such that” synonymous with the expressions “structured such that” and / or “established such that”.

[0009] According to an advantageous embodiment, the heating device can be arranged to extend into a discharge area located in the recess, particularly the central part, with a discharge opening leading into this discharge area. Heat is thus introduced into the pipe near the discharge opening, thereby protecting the discharge opening from icing particularly effectively and de-icing the discharge opening particularly effectively.

[0010] According to an advantageous embodiment, the humidifier can be configured with a heating element made of metal, which is connected, preferably directly, to a heating device on one side and to a pipe on the other. In this way, the heating device can directly transfer heat to the heating element, which in turn can directly transfer heat to the pipe. Through this connection, which preferably generates heat through direct contact, heat conduction occurs from the heating device through the heating element to the pipe, thereby enabling the heating device to operate particularly efficiently and requiring relatively little electrical energy.

[0011] According to an advantageous embodiment, the heating element can be configured with a shell made of metal forming a cavity, the shell being arranged within the cavity and a drain opening located within the shell. Preferably, water accumulated in the shell is collected in the cavity. By constructing a cavity in the shell of the heating element, the heat supply to the water accumulated in the shell is simplified or concentrated. This improves the efficiency of the heating device.

[0012] According to an advantageous embodiment, a seal, particularly an annular seal, can be provided between the shells in the recess. This prevents water from entering the rear space away from the recess within the recess.

[0013] According to an advantageous embodiment, the heating element and the shell can be manufactured integrally, such that the shell is formed from an integral region of the heating element. For example, the heating element is a casting that already has the shell. This integral manufacturing is particularly advantageous at low cost. However, improved heat conduction within the integral heating element is especially advantageous.

[0014] According to an advantageous embodiment, the heating element may have at least one rib made of metal extending into the cavity, such that the rib is in direct contact with the water collected in the cavity. With this type of rib, it is possible to easily prevent or facilitate the thawing of the water in the cavity from freezing. By heating the heating element, the corresponding rib is also heated, thereby allowing heat to be easily transferred to the water via the rib.

[0015] According to an advantageous embodiment, the corresponding ribs can be arranged on the shell mentioned above. Therefore, heating of the heating element causes the shell to conduct heat outwards at its edges into the water located in the recess, while the corresponding ribs conduct heat from within the recess into the water. Thus, the heating device operates with particularly high efficiency.

[0016] According to an advantageous embodiment, the heating element can be integrally manufactured with the corresponding ribs, such that the respective ribs are formed from integrally formed regions of the heating element. For example, the heating element can be a casting already equipped with the corresponding ribs. This integral construction improves heat conduction down to the respective ribs.

[0017] Here, the following configuration is particularly advantageous: in this configuration, the heating element is integrally manufactured with the shell and the corresponding ribs, such that the shell and the corresponding ribs are each formed by a region integrally formed of the heating element. For example, the heating element can be a casting already equipped with the shell and the corresponding ribs.

[0018] According to an advantageous embodiment, the heating element may have at least two ribs of this type, said at least two ribs being arranged and configured such that said at least two ribs form a free space therebetween, which fluidly connects a discharge area located in a recess, particularly the central one, to an external area of ​​the housing interior space located outside the recess, with a discharge opening opening into the discharge area. In the installed state of the humidifier, the external area outside the recess is located above the recess in the housing interior space. The free space constructed between the two ribs represents a discharge channel that fluidly connects the external area to the discharge area, with a discharge opening located in the discharge area. The heating ribs protect the water in this free space from freezing or allow the water to preferably be thawed there. Therefore, in the event of freezing, the free space or discharge channel can preferably be thawed, allowing water to be quickly drained from the housing through the free space or discharge channel.

[0019] According to an advantageous embodiment, the cavity can be surrounded by a cavity edge that abuts the bottom of the housing. Suitably, the two ribs can extend parallel to each other to or beyond the cavity edge. Therefore, the free space, or the aforementioned discharge channel, also extends to or beyond the cavity edge, thereby enabling rapid and efficient discharge even at relatively high water levels within the housing.

[0020] According to an advantageous embodiment, the heating element may have a tube receptacle made of metal, which opens toward a cavity, and a tube extends into the tube receptacle such that a discharge opening leads into the tube receptacle or the cavity. Therefore, heating the heating element results in heating the tube receptacle, which in turn heats the tube. This allows for particularly efficient heating of the tube in the area of ​​the discharge opening.

[0021] According to an advantageous embodiment, the tube receptacle can be configured with an internal thread, and the fitting has an external thread that matches the internal thread, allowing the fitting to be screwed into the tube receptacle. This simplifies the assembly of the humidifier. Simultaneously, it results in good heat conduction from the heating element to the fitting.

[0022] In principle, the following implementation method can be adopted: In this implementation method, the heating element and the pipe are manufactured as a single unit, such that the pipe is formed from a region integrally formed by the heating element. Obviously, the integrally manufactured heating element may also optionally have the shell and / or the corresponding ribs mentioned above. Then, the pipe receiving portion mentioned above can be omitted.

[0023] According to another advantageous embodiment, the heating element and the tube housing can be manufactured integrally, such that the tube housing is formed by a region integrally formed of the heating element. The heating element can be a casting already equipped with the tube housing.

[0024] According to an advantageous embodiment, the heating element can be integrally manufactured with the tube housing and the shell and / or corresponding ribs, such that the tube housing and the shell and / or corresponding ribs are each formed by integrally formed regions of the heating element. Accordingly, for example, a heating element configured as a casting can be equipped with a tube housing and a shell and / or corresponding ribs.

[0025] According to an advantageous embodiment, the heating device may have at least one PTC element coupled to the heating element in a heat-transfer manner. Here, PTC typically stands for Positive Temperature Coefficient. A key advantage of this type of PTC element is its high energy efficiency.

[0026] According to an advantageous embodiment, the bottom of the housing may have a through opening in a recess, through which a tube extends into the cavity. This simplifies the construction of the humidifier. Alternatively, the bottom of the housing may have an attachment opening in the recess, through which a heating element extends into the recess. This also simplifies the implementation of the humidifier.

[0027] According to another advantageous embodiment, the fitting can be sealed relative to the housing in the recess by means of an external seal, particularly an annular external seal. Alternatively, the fitting can be sealed relative to the heating element in the cavity, particularly in the pipe housing, by means of an internal seal, particularly an annular internal seal. These measures prevent unwanted leakage or outflow of water from the housing. Similarly, they prevent impurities from entering the housing.

[0028] Other important features and advantages of the invention are revealed by the dependent claims, the drawings, and the accompanying drawings.

[0029] It is evident that the features mentioned above and described below can be used not only in the corresponding combinations given, but also in other combinations or individually, without departing from the framework of the invention as defined by the claims. The separately marked components of a higher-level unit (e.g., apparatus, device, or component) mentioned above and still referred to below may form individual members or parts of that unit or may be regions or segments constituting the unit as a whole, even if this is otherwise shown in the drawings. Attached Figure Description

[0030] Preferred embodiments of the invention are shown in the drawings and described in more detail in the following description, wherein the same reference numerals refer to the same or similar or having the same function.

[0031] The attached figures schematically illustrate: Figure 1 A simplified cross-sectional view of the humidifier in the area at the bottom of the housing is shown. Figure 2 Show Figure 1 Enlarged detail II in the concave area, which includes a heating device, heating element, and tubing. Figure 3 Showing the corresponding in Figure 2 Sectional view of section line III in the middle, Figure 4 The image shows a top isometric view of a heating element with heating devices and pipes. Figure 5 A bottom isometric view of a heating element with heating devices and pipes is shown. Detailed Implementation

[0032] according to Figure 1 The humidifier 1, shown only partially here, includes a housing 2 made of plastic, which has a housing bottom 3. The humidifier 1 is used to humidify a dry first gas flow 4 by means of a moist second gas flow 5. For this purpose, a membrane block 6, shown only simplified here, can be arranged in the housing 2 or in the internal space 40 of the housing surrounded by the housing 2. This membrane block can be passed through by the first gas flow 4 and the second gas flow 5 in a medium-separated manner, and the membrane block achieves the transfer of moisture from the second gas flow 5 to the first gas flow 4 by means of a membrane not shown in detail here.

[0033] A recess 7 is constructed in the bottom 3 of the shell, and a cavity 8 for collecting water 9 is provided in this recess. The water is generated in the shell 2, for example, by condensation and... Figure 1 and Figure 2 The arrow indicates this. A discharge opening 10 exists within the cavity 8. An outlet 11 for discharging water 9 is located on the exterior of the housing 2, and this outlet is fluidly connected to the discharge opening 10 for this purpose.

[0034] Furthermore, the humidifier 1 shown here has a metal tube 12 and an electric heating device 13. The tube 12 is arranged linearly and has two axially opposite tube ends 14, namely a first tube end 14.1 and a second tube end 14.2. The first tube end 14.1 is located inside the housing 2 and forms a discharge opening 10. The second tube end 14.2 is located outside the housing 2 and forms a water outlet 11. An internal tube space 15 exists inside the tube 12, which fluidly connects the two tube ends 14 to each other. Therefore, the discharge opening 10 and the water outlet 11 are fluidly connected to each other through the tube 12. The electric heating device 13 is directly or indirectly connected to the tube 12 by heat transfer. A discharge region 16 is constructed in the cavity 8, and the discharge opening 10 opens into this discharge region. Preferably, the discharge region 16 is centrally located in the cavity 8. Alternatively or additionally, the discharge region 16 is located at or forms the lowest part of the cavity 8. Suitablely, the heating device 13 is configured such that it extends to the discharge area 16. Thus, the heating device 13 can introduce heat into the pipe 12 in the discharge area 16, i.e., relatively close to the discharge opening 10.

[0035] according to Figures 1 to 5 In the preferred embodiment shown here, the humidifier 1 may further include a heating element 17 made of metal. The heating element 17 is connected to the heating device 13 directly or indirectly via heat transfer. On the other hand, the heating element 17 is connected to the pipe 12 directly or indirectly via heat transfer. Preferably, in the embodiment shown here, the heating element 17 is directly connected to both the heating device 13 and the pipe 12 via heat transfer. This means that the heating element 17 is in direct contact with both the heating device 13 and the pipe 12. The heating element 17 may have a shell 18 made of metal, which is shaped and positioned such that it forms a cavity 8. For this purpose, the shell 18 is arranged in the recess 7. Furthermore, a discharge opening 10 is located in the shell 18. The cavity 8 is surrounded by a cavity edge 19, which is adjacent to the bottom 3 of the shell and is also constructed on the heating element 17. The heating element 17 has a closed annular groove 20 on its radially outer side, adjacent to the edge 19 of the cavity. A heating element seal 21 is arranged in this annular groove, the heating element seal being suitably configured in annular shape. The heating element seal 21 seals the heating element 17 in the recess 7 relative to the housing 2.

[0036] Furthermore, the heating element 17 has at least one rib 22. In the example shown, purely exemplary and not limiting in general, exactly two ribs 22 are constructed on the heating element 17, namely the first rib 22.1 and the second rib 22.2. The corresponding ribs 22 extend in the cavity 8, more precisely, such that the ribs 22 come into contact with water 9 that may be present in the cavity 8. In the illustrated installed state of the humidifier 1, the cavity 8 is located in the lower part of the housing 2. Furthermore, the bottom 3 of the housing is inclined toward the cavity 8 or toward the recess 7, such that the water 9 generated in the housing 2 flows along the bottom 3 of the housing in the direction toward the recess 7 due to gravity and enters the cavity 8 there. Suitably, the corresponding ribs 22 are arranged in a straight line, and in the example shown here, they extend vertically. Here, the corresponding ribs 22 can originate from and project upward from the shell 18.

[0037] According to the preferred embodiment of the humidifier 1 shown herein, at least the two ribs 22 are provided, wherein the two ribs are arranged and configured such that the two ribs form a free space 23 therebetween, which fluidly connects the discharge region 16 to the outer region 24 of the housing interior space 40, wherein the outer region 24 is located outside the cavity 8 within the housing interior space 40. In the normal installed state of the humidifier 1, the outer region 24 is located above the cavity 8 and within the housing interior space 40. The free space 23 forms a discharge channel 25 that extends from the outer region 24 to the discharge region 16. In the example shown, the first rib 22.1 protrudes from the shell 18, while the second rib 22.2 protrudes from the tube housing 26, which will be discussed in more detail below. Thus, the discharge region 16 or the discharge channel 25 extends to below the second rib 22.2. If so much water accumulates in the shell 2, causing the water level above the cavity 8, ice can form under the corresponding low ambient temperature. This ice blocks the free space 23 and thus the drain channel 25, as well as the pipe 12 from the drain opening 10 to the outlet 11. The heating element 17 is heated by the heating device 13, thereby also heating the ribs 22. This preferably thaws the free space 23, thereby clearing the drain channel 25. Additionally, the pipe 12 is heated through direct contact between the heating element 17 and the pipe, and preferably thaws the ice contained therein. Therefore, the area that leads from the outer area 24 to the drain area 16 via the free space 23 or the drain channel 25, and from the drain opening 10 to the outlet 11 via the pipe 12, is primarily thawed and cleared. Thus, a large amount of water can be drained from the shell 2 relatively quickly. In the example shown, the two ribs 22 extend parallel to each other and beyond the edge 19 of the cavity, allowing relatively large ice blocks in the area of ​​the ribs 22 to be thawed and the drainage channel 25 to be cleared.

[0038] Furthermore, the heating element 17 may have a tube housing 26 made of metal and open toward the cavity 8. A fitting 12 extends into the tube housing 26, more specifically, so that the discharge opening 10 passes into the tube housing 26. In the illustrated example, the discharge region 16 is largely constructed within the tube housing 26. In the illustrated example, the tube housing 26 is further provided with an internal thread 27, and the fitting 12 has an external thread 28 that matches this internal thread. Accordingly, the fitting 12 is screwed into the tube housing 26. In the preferred example shown here, the heating element 17 is integrally manufactured with the housing 18, the cavity edge 19, the corresponding ribs 22, and the tube housing 26. Thus, the housing 18, the cavity edge 19, the corresponding ribs 22, and the tube housing 26 are each formed by integrally constituting regions of the heating element 17. This results in a high degree of integration for the heating element 17, which facilitates the assembly of the humidifier 1 and reduces manufacturing costs.

[0039] according to Figure 3 and Figure 5 The heating device 13 has at least one PTC element 29, which is coupled to the heating element 17 in a heat-transfer manner. For this purpose, the heating device 13 may have a metal plate 30, which contacts the PTC element 29 via a first contact strip 31. The metal plate 30 is directly and surface-mounted against the metal wall 32 of the heating element 17, thereby enabling large-area heat transfer between the heating device 13 and the heating element 17. Electrical contact of the PTC element 29 is achieved via the aforementioned first contact strip 31 and second contact strip 33. The two contact strips 31 and 33 lead to an electrical contact portion 34, which is arranged in a plug 35, serving as a carrier for the PTC element 29 and the metal plate 30.

[0040] By positioning the heating device 13 near the discharge opening 10, a shoulder 41 that rises in the height direction is created within the cavity 8. This shoulder transitions in a stepped manner through the metal wall 32 into a region of the cavity 8 that is lower in the height direction, where the discharge region 16 and the discharge opening 10 are located. Figure 4 The two ribs 22 are directly adjacent to the metal wall 32, which improves heat transfer on the ribs 22.

[0041] Figure 3 The sectional view contains a misalignment, which is caused by the following: according to Figure 2 Section line III extends centrally through the heating device 13 on one side and centrally through the pipe fitting 12 on the other, wherein the heating device 13 is arranged slightly offset from the pipe fitting 12 in the height direction. In the installed state of the humidifier, it extends vertically in the height direction.

[0042] according to Figure 3The bottom 3 of the housing has a through opening 36 in the recess 7, through which the tube 12 extends into the cavity 8. Here, according to Figure 3 The pipe fitting 12 is sealed relative to the housing 2 in the recess 7 by means of a suitably annular outer seal 37, and further sealed relative to the heating element 17 in the cavity 8, in this example, in the pipe receiving portion 26, by means of a suitably annular inner seal 38. Furthermore, the bottom 3 of the housing here has an attachment opening 39 in the recess 7, through which the heating device 13 extends into the recess 7. The heating device 13 or plug 35 is sealed relative to the housing 2 by means of a suitably annular plug seal 42.

[0043] List of reference numerals 1 Humidifier 2. Shell 3. Bottom of the casing 4 First gas flow 5 Second gas flow 6 membrane blocks 7. Depression 8. Cavity 9 Water 10 Discharge opening 11. Water outlet 12 Pipe Fittings 13 Heating device 14 Pipe end 15. Internal space of the tube 16 Discharge Area 17 Heating element 18 shells 19. Cavity edge 20 Annular groove 21 Heating element seal 22 ribs 23 Free Space 24 External Area 25 Discharge Channel 26-tube housing section 27 Internal thread 28 External thread 29 PTC components 30 Metal Plate 31 First contact strip 32 Metal Strip 33 Second contact strip 34 Electrical Contact Part 35 plug 36 Through opening 37 External seal 38 Internal seal 39 Attachment opening 40 Internal space of the shell 41 shoulder 42. Plug seal.

Claims

1. A humidifier (1) for humidifying a dry first gas stream (4) by means of a moist second gas stream (5), said humidifier being particularly suitable for fuel cell systems. - The humidifier has a housing (2) made of plastic, the housing having a recess (7) in the bottom (3) of the housing, and a cavity (8) in the recess for collecting water (9) generated in the housing (2). - in, There is a discharge opening (10) in the cavity (8). - Wherein, an outlet (11) for discharging water (9) is provided on the outside of the housing (2), the outlet being fluidly connected to the discharge opening (10). Its features are, - The humidifier (1) has a metal fitting (12) with a discharge opening (10) at one end and a water outlet (11) at the other end, and the discharge opening (10) and the water outlet (11) are fluidly connected. - The humidifier (1) has an electric heating device (13) which is directly or indirectly connected to the pipe (12) in a heat transfer manner.

2. The humidifier (1) according to claim 1, Its features are, - The heating device (13) extends to the discharge area (16) located in the cavity (8), and the discharge opening (10) opens into the discharge area.

3. The humidifier (1) according to claim 1 or 2. Its features are, - The humidifier (1) has a heating element (17) made of metal, which is connected to the heating device (13) on one side and to the pipe (12) on the other side in a heat transfer manner.

4. The humidifier (1) according to claim 3. Its features are, - The heating element (17) has a shell (18) made of metal, the shell forming the cavity (8), the shell being arranged in the recess (7) and the discharge opening (10) being located in the shell.

5. The humidifier (1) according to claim 4. Its features are, - The heating element (17) and the shell (18) are manufactured integrally, such that the shell (18) is formed by the integral region of the heating element (17).

6. The humidifier (1) according to any one of claims 3 to 5. Its features are, - The heating element (17) has at least one metal rib (22) extending in the cavity (8) such that the rib is in direct contact with the water (9) collected in the cavity (8).

7. The humidifier (1) according to claim 6 and claim 4 or 5. Its features are, - At least one such rib (22) is arranged on the shell (18).

8. The humidifier (1) according to claim 6 or 7. Its features are, - The heating element (17) and the corresponding rib (22) are manufactured integrally, such that the corresponding rib (22) is formed by the integrally formed area of ​​the heating element (17).

9. The humidifier (1) according to any one of claims 6 to 8. Its features are, - The heating element (17) has at least two ribs (22) of this type, the at least two ribs being arranged and configured such that the at least two ribs form a free space (23) therebetween, the free space fluidly connecting the discharge area (16) located in the cavity (8) with the external area (24) of the housing interior space (40) located outside the cavity (8), the discharge opening (10) opening into the discharge area.

10. The humidifier (1) according to claim 9. Its features are, - The cavity (8) is surrounded by a cavity edge (19), and the cavity edge is adjacent to the bottom (3) of the housing. - The two ribs (22) extend to or beyond the edge of the cavity (19).

11. The humidifier (1) according to any one of claims 3 to 10. Its features are, - The heating element (17) has a tube receptacle (26) made of metal, which is open toward the cavity (8), and the tube (12) extends into the tube receptacle, such that the discharge opening (10) leads into the tube receptacle (26) or into the cavity (8).

12. The humidifier (1) according to claim 11, Its features are, - The tube receiving portion (26) has an internal thread (27). - The pipe fitting (12) has an external thread (28) that matches the internal thread (27). - The fitting (12) is screwed into the pipe receiving part (26).

13. The humidifier (1) according to any one of the preceding claims. Its features are, - The heating element (17) and the tube housing (26) are manufactured integrally, such that the tube housing (26) is formed by the integral region of the heating element (17).

14. The humidifier (1) according to any one of claims 3 to 13. Its features are, - The heating device (13) has at least one PTC element (29) coupled to the heating body (17) in a heat transfer manner.

15. The humidifier (1) according to any one of the preceding claims. Its features are, - The bottom of the housing (3) has a through opening (36) in the recess (7), through which the tube (12) extends until it reaches the cavity (8), and / or - The bottom of the housing (3) has an attachment opening (39) on the recess (7), through which the heating device (13) extends into the recess (7).

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