Expansion tank and battery cooling system

Abstract

The invention relates to an expansion vessel (1) for a battery cooling system (3), - having a vessel housing (4) made of plastic, having a housing bowl (5) and at least one cover (6) which is placed on the housing bowl (5) from a first direction (7) and is connected to it in a sealing manner, - having a dryer device (8) having a dryer housing (11) made of plastic, a dryer insert (18) arranged therein and a dryer housing cover (19) closing the dryer housing (11), - in which the vessel housing (4) and the dryer housing (11) are formed in one piece and connected to each other in a communicating manner, - in which the dryer housing cover (19) can be placed on the dryer housing in a sealing manner from a second direction (20), - in which the first direction (7) extends orthogonally to the second direction (20).Thus, a low-cost and easy-to-maintain construction can be achieved. Figure for abstract: Fig. 3.

Description

Title of the invention: Expansion tank and battery cooling system

[0001] The present invention relates to an expansion tank comprising a dryer device and a battery cooling system comprising such an expansion tank.

[0002] Electric or hybrid vehicles are receiving increasing attention from consumers due to environmental aspects and are therefore becoming more and more widespread on the roads. In order to be able to increase both the autonomy and the performance of electric or hybrid vehicles of this type, it is sought to maintain a traction battery of such an electric or hybrid vehicle within an optimal temperature window for said traction battery, whereby temperature balancing devices, in particular cooling devices, are used in a known manner.

[0003] Such a battery cooling system for cooling in particular a traction battery also comprises an expansion tank in which air is stored as a compensation cushion for a temperature-induced volume change of the coolant. An increase in temperature causes the coolant to expand, which, if a resulting overpressure cannot escape, can lead to a high pressure load in the expansion tank and possibly damage it, which must therefore be avoided. Therefore, expansion tanks of this type generally have a connection to the environment in order to possibly be able to reduce a temperature-induced pressure difference by expelling air into the environment.In order to prevent or at least reduce the unwanted emission of hydrocarbon compounds into the environment, adsorbers can be provided, through which the air to be expelled into the environment flows and were arranged separately from the expansion tank. If the coolant cools down, it shrinks, resulting in a negative pressure in the expansion tank, which leads to a suction of fresh air from the environment. In order to prevent or at least reduce the unwanted input of moisture into the coolant, dryer cartridges have previously been provided in which a drying agent was arranged, through which the fresh air drawn in from the environment flows during the suction process and thus absorbs the moisture and dries the drawn-in fresh air.

[0004] The disadvantage of known expansion vessels, however, is their relatively complex and therefore expensive manufacture and maintenance.

[0005] The present invention therefore aims to propose an improved or at least alternative embodiment of an expansion vessel to counter the problem, by means of which the known disadvantages of the state of the art can be overcome.

[0006] The present invention is based on the general idea of ​​arranging for the first time a dryer device of an expansion tank of a battery cooling system on the side of the tank housing, wherein at least one dryer housing is formed in one piece with the tank housing, in particular with a housing bowl of the tank housing, but can be opened laterally and can thus be manufactured inexpensively together with the tank housing, in particular with the housing bowl of the tank housing, and can at the same time be equipped more easily with a dryer insert. The lateral access to the dryer device makes it possible to considerably simplify maintenance, in particular in the case of an expansion tank installed in a motor vehicle.The expansion vessel according to the invention for a battery cooling system has a vessel housing made of plastic having a housing bowl and at least one cover which is placed on the housing bowl from a first direction and is connected to it in a sealing manner. Furthermore, the dryer device is provided having a dryer housing made of plastic, a dryer insert arranged therein and a dryer housing cover closing the dryer housing, wherein the vessel housing, in particular the housing bowl of the vessel housing, and the dryer housing are formed in one piece and connected to each other in a communicating manner and the dryer housing cover can be placed on the dryer housing in a sealing manner from a second direction.In concrete terms, this means that the housing bowl and the dryer housing are designed as a coherent one-piece element, whereby the cover can be placed on the housing bowl and the dryer housing cover can be placed on the dryer housing. The first direction then runs orthogonally to the second direction. In the event of excess pressure in the expansion vessel, a first valve allows air from the expansion vessel to enter the environment, while in the event of negative pressure in the expansion vessel, a second valve allows fresh air from the environment to enter the expansion vessel. The term "fresh air" can / must refer to the surrounding air here.This not only enables economical manufacturing, since the vessel housing, in particular the housing bowl of the vessel housing, and the dryer housing can be manufactured in a common plastic injection molding process, but it also enables relatively simple loading of the dryer device with drying agent, in particular during maintenance in the case of an expansion vessel mounted in a . motor vehicle. In addition, welding the dryer housing cover simultaneously compresses the drying agent. This reduces the surface area subjected to pressure and thus the load on the weld. In other embodiments, the sealing or joining surface subjected to pressure is also reduced.

[0007] According to an advantageous improvement of the expansion vessel according to the invention, the dryer device has a drying agent arranged in a first air-permeable bag or a dimensionally stable drying body made of a sintered, extruded or injected drying agent, or a dryer insert designed as a dryer cartridge having a drying agent arranged therein. In the case of a drying agent in a first air-permeable bag, it is possible to achieve a particularly simple form adaptation and thus to utilize even angular construction spaces. In the case of a dimensionally stable drying body, handling is particularly facilitated. The dimensionally stable drying body can then be adapted, with regard to its outer contour, to an inner contour of the dryer housing, which makes it possible to achieve optimal use of the space and to avoid undesirable bypass flow.A dryer insert made as a dryer cartridge offers the advantage of easy handling.

[0008] In practice, the first bag is made of a fabric, in particular a polyester fabric or a polyamide fabric. Polyester is lightweight and furthermore does not absorb moisture, so that the moisture absorption is solely due to the drying agent. The formation of the bag from polyester fabric further offers the advantages of high strength, good machinability and weldability as well as high air permeability. The use of polyamide offers advantages such as high strength and tear resistance, as well as high elasticity and a long service life.

[0009] Preferably, the drying agent is arranged as a bulk product in the first bag. The drying agent thus adapts optimally to an inner contour of the dryer housing and can be accommodated therein in a form-fitting and positionally fixed manner. This embodiment also avoids manufacturing tolerances that can lead to undesirable bypass flow in rigid housings.

[0010] In another advantageous embodiment, the drying agent comprises silica gel or zeolite. Silica gel is a colorless silicon dioxide of gelatinous, rubbery or solid consistency. It has a large internal surface area (about 600 m2 / g) and is highly hydrophilic. Zeolite can absorb about 20% of its own weight in moisture and thus produces heat, which can also promote drying. The use of zeolite provides a strong drying effect. dehumidification even at low humidity, while silica gel has high water absorption and is also inexpensive.

[0011] In a particularly preferred embodiment, a spring is provided for pre-tensioning the first bag. A spring is provided, which pre-tensions the drying agent in the first bag or the dryer cartridge. Such a spring makes it possible to achieve a reliable and positionally fixed arrangement of the drying agent in the dryer housing, the spring pre-tensioning at the same time preventing the drying agent from producing, during operation, noises which are perceived, for example, as annoying. Such a spring can, for example, be implemented as an inexpensive helical spring. A pre-tension also prevents the crushing of the drying agent arranged as a bulk product in the first bag during operation. The pre-tensioning also ensures the peripheral support of the drying agent or bag against the dryer housing, so that the air to be dried is forced to pass through the drying agent and cannot bypass it.

[0012] In another advantageous embodiment, an adsorber is provided comprising a plastic adsorber housing, an activated carbon insert arranged therein and comprising activated carbon and an adsorber housing cover closing the adsorber housing. The adsorber may for example be an HC adsorber. The vessel housing, in particular the housing bowl of the vessel housing, and the adsorber housing are then made in one piece and connected to each other in a communicating manner, whereby the vessel housing, in particular the housing bowl of the vessel housing, together with the dryer housing and the adsorber housing, can be manufactured in a common, inexpensive plastic injection molding process.The adsorber housing cover can then be tightly fitted onto the adsorber housing from the second direction, allowing maintenance of the adsorber and the dryer device from the same direction.

[0013] In a particularly preferred embodiment of the expansion vessel according to the invention, the activated carbon of the adsorber is placed in a second air-permeable bag. The activated carbon arranged in a second air-permeable bag again allows particularly simple shape adaptation and the use of even angular construction spaces. In addition, undesirable bypass flow can be avoided.

[0014] Conveniently, the second bag is also made of a fabric, in particular a polyester fabric or a polyamide fabric. Thus, the advantages described in particular for the first polyester bag can also be obtained for the second bag.

[0015] In another advantageous embodiment, a spring is provided to prestress the second bag and thus the activated carbon. Such a spring makes it possible to obtain a reliable and fixed arrangement in position of the activated carbon in the adsorber housing, The spring pre-tensioning also prevents the activated carbon from being crushed during operation and thus losing its effectiveness.

[0016] It is practical if at least one cover is welded, clipped, screwed or glued to the housing bowl. In addition or alternatively, the dryer housing cover can be welded, clipped, screwed or glued to the dryer housing, or the adsorber housing cover can be welded, clipped, screwed or glued to the adsorber housing. A removable connection between the dryer housing cover and the dryer housing or between the adsorber housing cover and the adsorber housing then offers advantages during a possibly necessary replacement of the drying agent or the activated carbon.

[0017] Advantageously, the dryer housing cover and the adsorber housing cover are produced in one piece, in particular in the form of a one-piece plastic injection-molded part. This reduces manufacturing costs and simplifies assembly and maintenance.

[0018] Preferably, at least one of the following components is made from polyoxymethylene (POM) or polyketone: cover, housing bowl, dryer housing cover, dryer housing, adsorber housing cover, adsorber housing. POM is a semi-crystalline thermoplastic with high mechanical strength and rigidity and, in addition, high wear resistance and low moisture absorption, which is very advantageous, in particular when used for the expansion vessel according to the invention, since in this case, water infiltration or moisture absorption increases the electrical conductivity of a dielectric coolant. It is also possible to use polyketone as the plastic.Polyketones (PK) are high-performance thermoplastic polymers that exhibit high impact strength, low wear, good solvent resistance, and low water absorption. Polyketone also exhibits high environmental compatibility. In order to further increase mechanical strength and wear resistance, the plastic material may have glass fibers, especially 25% glass fibers, in particular be realized as POM GF-25.

[0019] The present invention is further based on the general idea of ​​equipping a battery cooling system with an expansion tank described in the preceding paragraphs and thus applying to the battery cooling system the advantages described regarding the expansion tank. Concretely, the advantages of a battery cooling system equipped with the expansion tank according to the invention lie in inexpensive manufacturing and easy maintenance.

[0020] Other important features and advantages of the invention will emerge from the subclaims, the diagrams and the description of the corresponding figures with the aid of the diagrams.

[0021] It is self-evident that the above-mentioned features and those which will be explained later can be used not only in the combination respectively indicated, but also in other combinations or alone, without departing from the scope of the present invention. The parts of a higher unit, such as for example a device, an apparatus or an arrangement, which are mentioned above and will be mentioned later, and are designated separately, can constitute separate elements or components of this unit or be integral areas or sections of this unit, even if this is shown differently in the diagram.

[0022] Preferred embodiments of the invention are shown in the diagrams and are explained in more detail in the following description, the same reference signs referring to identical or similar or functionally identical components.

[0023] The following are shown, respectively schematically:

[0024] [Fig-1]: a view of an expansion vessel according to the invention of a system of battery cooling according to the invention,

[0025] [Fig.2]: a representation identical to that of [Fig.l], but in another perspective,

[0026] [Fig.3]: a sectional representation of an expansion vessel according to the invention in the area of ​​a dryer device,

[0027] [Fig.4]: a detailed representation of [Fig.3],

[0028] [Fig.5]: a sectional representation of an expansion vessel according to the invention in the area of ​​an adsorber,

[0029] [Fig.6]: a detailed representation of [Fig.5].

[0030] According to Figures 1 to 6, an expansion vessel 1 according to the invention for air 2 of a battery cooling system 3 according to the invention has a vessel housing 4 made of plastic material having a housing bowl 5 and two covers 6 which are placed on the housing bowl 5 from a first direction 7 and which are connected thereto in a sealed manner. The two covers 6 can then also be made from a single piece and thus form a common cover 6 for covering the housing bowl 5. Furthermore, the expansion vessel 1 has a dryer device 8 comprising a dryer housing 11 made of plastic, a dryer insert 18 arranged therein and a dryer housing cover 19 closing the dryer housing 11, the vessel housing 4, in particular the housing bowl 5 of the vessel housing 4, and the dryer housing 11 being made from a single piece and connected to each other in a communicating manner.The dryer housing cover 19 can . then be placed in a sealed manner on the dryer housing 11 from a second direction 20, the first direction 7 extending orthogonally to the second direction 20. This not only enables economical manufacturing, since the vessel housing 4, in particular the housing bowl 5 of the vessel housing 4, and the dryer housing 11 can, for example, be manufactured in a common plastic injection molding process, but also enables relatively simple equipment of the dryer device 8 with the dryer insert 18 and the drying agent 21 contained therein, in particular during maintenance of an expansion vessel 1 installed in a motor vehicle.

[0031] The dryer device 8 then preferably has a drying agent 21 arranged in a first air-permeable bag 15, the dryer device 8 also being able to alternatively have a non-deformable drying body 17 consisting of a sintered, extruded or injected drying agent 21. The two embodiments are shown in [Fig. 4], it being understood that they are only used alternatively.

[0032] If [Fig. 4] is observed, a dryer device 8 can be recognized in which the first bag 15 is made from a fabric, in particular from a polyester fabric or a polyamide fabric. Of course, other materials resistant to the coolant in the battery cooling system 3 are also conceivable. The drying agent 21 can be arranged as a bulk product in the first bag 15, for example in the form of silica gel or zeolite in the form of beads. The outer contour of the dryer insert 18 can thus optimally adapt to the inner contour of the dryer housing 11, which enables a positive and reliable fit. The positive fit in particular makes it possible to prevent an undesired bypass flow of the fresh air 2a drawn in.

[0033] The drying agent 21 used for the dimensionally stable drying body 17 may also comprise silica gel or zeolite. According to [Fig. 4], the dimensionally stable drying body 17 made of pressed, sintered, extruded or injected drying agent 21 may then have an outer contour which is complementary to the inner contour of the dryer housing 11 and which thus also prevents an undesirable bypass flow of the fresh air 2a drawn in. The dimensionally stable drying body 17 makes it possible to dispense with an additional housing, such as for example the first bag 15, which reduces manufacturing costs.

[0034] The expansion vessel 1 according to the invention may further have an adsorber 12 comprising an adsorber housing 22 made of plastic, an activated carbon insert 23 arranged therein and comprising activated carbon 25 and an adsorber housing cover 24 closing the adsorber housing 22.

[0035] An opening 27 may be provided in the adsorber housing cover 24, through which air 2 can be expelled into the environment in the event of a corresponding overpressure.

[0036] The vessel housing 4, in particular the housing bowl 5 of the vessel housing 4, and the adsorber housing 22 are then made in one piece and connected to each other in a communicating manner, which makes it possible to manufacture the vessel housing 4 together with the dryer housing 11 and the adsorber housing 22 in a common, inexpensive plastic injection molding process. The adsorber housing cover 24 can then also be placed in a sealed manner on the adsorber housing 22 from the second direction 20, which allows maintenance of the adsorber 12 and the dryer device 8 from the same direction, here the second direction 20.

[0037] The dryer housing cover 19 and the adsorber housing cover 24 can be produced in one piece, in particular as a one-piece plastic injection molded part, which reduces manufacturing costs and simplifies handling. Alternatively, the dryer housing cover 19 and the adsorber housing cover 24 can be produced separately from each other.

[0038] The activated carbon 25 of the activated carbon insert 23 or of the adsorber 12 may be arranged in a second air-permeable bag 26.

[0039] In the event of overpressure in the expansion tank 1, a first valve 9 allows air 2 from the expansion tank 1 to enter the environment, the air 2 being able to pass through an adsorber 12 to be purified. The expulsion of air 2 through the adsorber 12 makes it possible in particular to reliably retain pollutants, such as hydrocarbons. In the event of a negative pressure in the expansion tank 1, fresh air 2a from the environment is sucked into the expansion tank 1 via a second valve 10. The battery cooling system 3 is then connected to the expansion tank 1 so as to communicate via a connecting means 28, for example a Quick-Connector type element. The suction of fresh air 2a from the environment into the expansion vessel 1 is carried out via the second valve 10 and the dryer device 8 in which the sucked-in fresh air 2a is dried.

[0040] The first valve 9 is then arranged in the intermediate wall 13 which separates the adsorber 12 from the interior space 16 of the vessel housing 4. The second valve 10 is then arranged in an exterior wall of the vessel housing 4. Certainly, the second valve 10 described previously and another pressure relief valve, through which an expulsion of air 2 coming from the expansion vessel 1 in the environment is carried out, can also be arranged in the outer wall of the vase housing 4.

[0041] If we continue to observe Figures 5 and 6, we can see that a spring 14' is arranged at the adsorber 12, which spring prestresses the adsorber 12 or the activated carbon 25 against the vessel housing 4, here specifically against an intermediate wall 13. The spring 14' makes it possible to obtain a fixation of the adsorbent 12 without vibrations and therefore without rattling. This makes it possible in particular to improve the comfort of the user due to a low noise level and to avoid the grinding of the activated carbon 25 in the activated carbon insert 23.

[0042] The vessel housing 4, i.e. the housing bowl 5 and / or the cover 6, but also the dryer housing 11, the dryer housing cover 19, the adsorber housing 22 and the adsorber housing cover 24 can then be produced as plastic injection-molded parts, which not only enables high-quality production, but also at lower cost.

[0043] At least one cover 6 can be welded, clipped, screwed or glued to the housing bowl 5. Additionally or alternatively, the dryer housing cover 19 can be welded, clipped, screwed or glued to the dryer housing 11 and / or the adsorber housing cover 24 can be welded, clipped, screwed or glued to the adsorber housing 22. In particular, a clip connection or a screw connection has the great advantage of allowing the dryer housing 11 or the adsorber housing 22 to be opened to replace the dryer insert 18 or the activated carbon insert 23, and to be able to continue to use said housing after the replacement of the dryer insert 18 or the activated carbon insert 23.

[0044] At least one of the following components can be made of polyoxymethylene (POM) or polyketone, i.e. a plastic material with high strength and low moisture absorption, which is particularly advantageous, in particular for an expansion vessel 1 for air 2 of a battery cooling system 3: cover 6, housing bowl 5, dryer housing cover 19, dryer housing 11, adsorber housing cover 24, adsorber housing 22. In order to further increase the strength and wear resistance of the vessel housing 4, the plastic material can additionally have glass fibers, in particular a proportion of 25% glass fibers in the plastic material.

[0045] All things considered, the expansion tank 1 according to the invention and the battery cooling system 3 according to the invention make it possible to create an extremely economical and space-optimized solution.

Claims

Claims

1. Expansion vessel (1) for a battery cooling system (3), - comprising a vessel housing (4) made of plastic, having a housing bowl (5) and at least one cover (6) which is placed on the housing bowl (5) from a first direction (7) and which is connected in a sealing manner thereto, - comprising a dryer device (8) having a dryer housing (11) made of plastic, a dryer insert (18) arranged therein and a dryer housing cover (19) closing the dryer housing (11), - wherein the vessel housing (4) and the dryer housing (11) are formed in one piece and connected to each other in a communicating manner, - wherein the dryer housing cover (19) can be placed in a sealing manner on the dryer housing (11) from a second direction (20), - in which the first direction (7) extends orthogonally to the second direction (20),- comprising a first valve (9) through which, in the event of excess pressure in the expansion tank (1), air (2) from the expansion tank (1) enters the environment, - comprising a second valve (10) through which, in the event of a negative pressure in the expansion tank (1), fresh air (2a) from the environment enters the expansion tank (1).,

2. Expansion vessel according to claim 1, characterized in that - the dryer device (8) has a drying agent (21) arranged in a first air-permeable bag (15), or - the dryer device (8) has a dimensionally stable drying body (17) made of a sintered, extruded or injected drying agent (21), or - the dryer insert (18) is designed as a dryer cartridge having a drying agent (21) arranged therein.

3. Expansion vessel according to claim 2, characterized in that the first bag (15) is made from a fabric, in particular from a polyester fabric or a polyamide fabric.

4. Expansion vessel according to claim 2 or 3, characterized in that the drying agent (21) is arranged as a bulk product in the first bag (15).

5. Expansion vessel according to one of claims 2 to 4, characterized in that the drying agent (21) comprises silica gel or zeolite.

6. Expansion vessel according to one of claims 2 to 5, characterized in that a spring (14) is provided, which pre-tensions the drying agent (21) in the first bag (15) or the dryer cartridge.

7. Expansion vessel according to one of the preceding claims, characterized in that - an adsorber (12) is provided having an adsorber housing (22) made of plastic, an activated carbon insert (23) arranged therein and having activated carbon (25) and an adsorber housing cover (24) closing the adsorber housing (22), - the vessel housing (4) and the adsorber housing (22) are made in one piece and connected to each other in a communicating manner, - the adsorber housing cover (24) can be placed sealingly on the adsorber housing (22) from the second direction (20).

8. Expansion vessel according to claim 7, characterized in that the activated carbon (25) of the adsorber (12) is arranged in a second bag (26) permeable to air.

9. Expansion vessel according to claim 8, characterized in that a spring (14') is provided, which pre-tensions the second bag (26) and further the activated carbon (25) arranged therein.

10. Expansion vessel according to one of claims 6 to 9, characterized in that - at least one cover (6) is welded, clipped, screwed or glued to the housing bowl (5), and / or - the dryer housing cover (19) is welded, clipped, screwed or glued to the dryer housing (11), and / or - the adsorber housing cover (24) is welded, clipped, screwed or glued to the adsorber housing (22).

11. Expansion vessel according to one of claims 7 to 10, characterized in that the dryer housing cover (19) and the adsorber housing cover (24) are produced in one piece, in particular in the form of a one-piece plastic injection-moulded part.

12. Expansion vessel according to one of claims 1 to 11, characterized in that at least one of the following components is made of polyoxymethylene (POM) or polyketone, cover (6), housing bowl (5), dryer housing cover (19), dryer housing (11), adsorber housing cover (24), adsorber housing (22).

13. Expansion vessel according to one of claims 6 to 12, characterized in that the plastic material has glass fibers, in particular a proportion of 25% of glass fibers in the plastic material.

14. Battery cooling system (3) comprising an expansion tank (1) according to one of the preceding claims.

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