Cooling system and vehicle including such cooling system

Abstract

A cooling system comprising a cooling circuit (10) having a degassing device (40) arranged in the cooling circuit for separating gas bubbles from a coolant circulating therein. The degassing device comprises a degassing chamber (41) having a coolant inlet (43) connected to a supply pipe (15) of the cooling circuit; a first coolant outlet (44) connected to a coolant pump (12) of the cooling circuit; and a second coolant outlet (45) connected to an expansion tank (30) via a static line (5). The degassing chamber has a larger cross-sectional dimension than the supply pipe. The second coolant outlet (45) is located relative to the coolant inlet (43) and the first coolant outlet (44) in such a position that a coolant flow in the degassing chamber between the coolant inlet and the first coolant outlet will move migrating gas bubbles in the longitudinal direction of the degassing chamber towards the second coolant outlet (45).

Description

Technical Field

[0001] The present invention relates to a cooling system and a vehicle comprising such a cooling system. Background Art

[0002] Some of the vehicle components included in a motor vehicle can be cooled by means of a coolant circulating in a cooling circuit of a cooling system. The absorbed heat can be discharged from the circulating coolant to the surrounding environment via a radiator, which is arranged in the cooling circuit and at the front end of the vehicle. The coolant flowing through the radiator is cooled by means of ambient air, which is blown towards the radiator when the vehicle is in motion.

[0003] When vehicle components are cooled by coolant circulating in a cooling circuit, they release heat into the coolant, which in turn heats and expands. The resulting increase in the total coolant volume in the cooling circuit depends on the initial coolant volume and the temperature increase. To prevent excessive pressure increases in the cooling circuit, the cooling circuit is equipped with an expansion tank, which can accommodate the excess coolant volume generated by the expansion of the coolant. Another important function of conventional expansion tanks in cooling systems of the type described above is that the coolant received in the expansion tank should be degassed in the expansion tank before leaving the expansion tank. In conventional cooling systems of the type that connect the cooling circuit to an expansion tank in a motor vehicle, there is a small, continuous flow of coolant from the cooling circuit to the expansion tank via one or more degassing lines and from the expansion tank back to the cooling circuit via so-called static lines. Air accompanying the coolant entering the expansion tank is intended to rise to the surface of the coolant volume received in the expansion tank, accumulating in the air-filled space at the upper portion of the expansion tank. This degasses the coolant in the expansion tank. Alternatively, the cooling system may include a separate degassing device, which is arranged in the cooling circuit for separating gas bubbles from the coolant circulating in the cooling circuit, wherein the degassing device is connected to the expansion tank via a static line so as to allow gas bubbles separated from the coolant in the degassing device to migrate upward in the static line to the expansion tank. A cooling system of the latter type is previously known, for example, from US Pat. No. 7,395,787 B1.

[0004] By using a degassing device of the type disclosed in US Pat. No. 7,395,787 B1, it is possible to degas the coolant in the cooling circuit without requiring any coolant flow from the cooling circuit to an expansion tank connected to the cooling circuit, which in turn means that conventional degassing lines for supplying coolant from the cooling circuit to the expansion tank can be dispensed with. Such degassing lines can be quite expensive and can also take up a lot of space, so being able to dispense with them is advantageous.

[0005] The degassing device included in the cooling system disclosed in US Pat. No. 7,395,787 B1 includes a degassing chamber having an outlet at its top that is connected to an expansion tank via a static line. The cross-sectional dimensions of the degassing chamber are substantially larger than the cross-sectional dimensions of the coolant supply pipe leading to the degassing chamber, thereby slowing the coolant flow and increasing the coolant flow's residence time in the degassing chamber. This, in turn, allows bubbles in the coolant to migrate within the degassing chamber to the outlet at the top of the degassing chamber and then further migrate to the expansion tank via the static line.

[0006] Purpose of the Invention

[0007] It is an object of the present invention to achieve a further development of a cooling system of the type mentioned above, in order to provide a cooling system which is improved in at least some aspects. Summary of the Invention

[0008] According to the invention, the above-mentioned object is achieved by means of a cooling system having the features defined in the present application.

[0009] The cooling system of the present invention comprises:

[0010] Cooling circuit;

[0011] a coolant pump, the coolant pump being used to circulate the coolant in the cooling circuit;

[0012] an expansion tank for accumulating coolant; and

[0013] a degassing device arranged in the cooling circuit for separating gas bubbles from the coolant circulating in the cooling circuit, wherein the degassing device is connected to the expansion tank via a static line and comprises a degassing chamber having:

[0014] a coolant inlet connected to a supply pipe of the cooling circuit so as to allow the coolant circulating in the cooling circuit to flow from the supply pipe into the degassing chamber via the coolant inlet,

[0015] a first coolant outlet connected to the coolant pump so as to allow coolant to flow from the degassing chamber to the coolant pump via the first coolant outlet, wherein the coolant inlet and the first coolant outlet are spaced apart from each other in a longitudinal direction of the degassing chamber, and

[0016] a second coolant outlet connected to the expansion tank via the static line and located at a higher position relative to a local gravity vector gv than the first coolant outlet when the cooling system is mounted to a vehicle and the vehicle is in an upright use position on a horizontal surface.

[0017] The cross-sectional size of the degassing chamber is larger than that of the supply pipe, thereby allowing air bubbles flowing with the coolant flowing through the supply pipe to enter the degassing chamber through the coolant inlet and then migrate to the second coolant outlet in the degassing chamber.

[0018] According to the present invention, the aforementioned second coolant outlet, i.e., the coolant outlet connected to the expansion tank via a static line, is located relative to the coolant inlet and the first coolant outlet such that coolant flow between the coolant inlet and the first coolant outlet in the degassing chamber will move the migrating bubbles in the longitudinal direction of the degassing chamber toward the second coolant outlet. Furthermore, when the cooling system is mounted on a vehicle and the vehicle is positioned in an upright use position on a horizontal surface, the first coolant outlet is arranged at a higher position relative to the local gravity vector gv than the coolant inlet.

[0019] As a result, bubbles migrating within the degassing chamber toward the second coolant outlet do not need to move against the flow direction of the coolant within the degassing chamber, and the coolant flow within the degassing chamber therefore does not resist the migration of bubbles toward the second coolant outlet. Instead, the coolant flow within the degassing chamber promotes the migration of bubbles within the degassing chamber toward the second coolant outlet, thereby enabling efficient separation of bubbles from the circulating coolant within the degassing chamber. It has been demonstrated that directing the coolant flow within the degassing chamber in the direction of the expected bubble migration, compared to directing the coolant flow within the degassing chamber against the expected bubble migration direction, allows for efficient bubble separation at a higher coolant flow rate within the degassing chamber. It has also been demonstrated that directing the coolant flow within the degassing chamber in the direction of the expected bubble migration, compared to directing the coolant flow within the degassing chamber against the expected bubble migration direction, requires a smaller difference in cross-sectional dimensions between the degassing chamber and the coolant supply pipe leading thereto, which in turn means that the cross-sectional dimensions of the degassing chamber can be reduced. Reducing the difference in cross-sectional dimensions between the degassing chamber and the coolant supply pipe leading to the degassing chamber will also advantageously reduce the pressure drop across the degassing chamber. The degassing device is located at a lower position than the expansion tank to allow gas bubbles separated from the coolant in the degassing device to migrate upward in the static line toward the expansion tank.

[0020] Furthermore, when the cooling system is mounted on a vehicle and the vehicle is positioned in an upright usage position on a horizontal surface, by arranging the first coolant outlet at a higher position than the coolant inlet relative to the local gravity vector gv, the coolant flow will have an upwardly directed flow component, i.e., a flow component parallel to and pointing opposite the local gravity vector gv. Consequently, the coolant flow in the degassing chamber will act on the air bubbles with a force having a vector component parallel to and pointing opposite the local gravity vector gv. Consequently, the air bubbles will be pushed upward toward the second outlet and the static line. This improves the separation of the air bubbles from the coolant and their evacuation into the expansion chamber. This effect is particularly pronounced for small bubbles with low terminal velocities, thereby enabling efficient degassing.

[0021] With the degassing device described above, the coolant in the cooling circuit can be degassed in a simple and efficient manner using components of simple construction that can be produced at low cost.

[0022] The cross-sectional dimensions of the degassing chamber are preferably substantially larger than those of the supply pipe, such that the ratio between the flow rate of coolant flowing through the degassing chamber and the flow rate of coolant flowing through the supply pipe between the coolant inlet and the first coolant outlet is 1:2 or less, preferably 1:3 or less. Accordingly, by appropriately controlling the coolant pump, the coolant flow through the cooling circuit can be adjusted in such a way that the coolant flow rate in the supply pipe is high enough to allow the coolant to move bubbles along the supply pipe and into the degassing chamber, while the coolant flow rate in the expansion chamber is low enough to allow the bubbles to migrate within the degassing chamber to the second coolant outlet of the degassing chamber. If the coolant flow rate in the supply pipe is too low, bubbles may become stuck in the supply pipe. If the coolant flow rate in the degassing chamber is too high, the coolant may carry bubbles with it and leave the degassing chamber via the first coolant outlet. The coolant pump can be controlled in such a way that the coolant circulating in the cooling circuit is continuously degassed. As an alternative, however, the coolant pump may be configured to adapt the coolant flow in the cooling circuit in such a way that degassing is achieved intermittently or only in specific cases.

[0023] According to an embodiment of the present invention, the degassing chamber has an elongated shape and is arranged with its longitudinal axis vertical, wherein the coolant inlet is located at a lower position than the first coolant outlet and the second coolant outlet. A degassing device having such a degassing chamber has a relatively simple construction and can be produced in a simple and cost-effective manner.

[0024] According to another embodiment of the present invention, the degassing chamber has an elongated shape and is arranged with its longitudinal axis tilted at an angle of 0-90° relative to the horizontal plane, preferably an angle greater than 0° and less than 90°, more preferably an angle of 10-90°, and most preferably 15-90°. In this context, the horizontal plane refers to a plane whose normal is parallel to the principal gravity vector. When the degassing chamber is arranged with its longitudinal axis tilted at an angle greater than 0° relative to the horizontal plane, bubbles can rise within the degassing chamber and strike the inclined upper wall surface within the degassing chamber. As a result, under the influence of the coolant flow between the coolant inlet and the first coolant outlet in the degassing chamber, the bubbles are transported along this wall surface toward the second coolant outlet. Furthermore, even at very low flow rates, bubbles that have separated from the coolant will rise toward the static line due to their buoyancy. Thus, improved degassing is achieved. By having an inclination between 10-90°, the chamber will be tilted toward the horizontal plane in most situations, even when the vehicle is traveling on a downward slope. Therefore, the aforementioned effect is maintained even when the vehicle is moving on hilly terrain. By inclining the chamber between 15 and 90 degrees, it is ensured that for the vast majority of standard travels, the chamber will be tilted relative to the horizontal plane. This ensures that the degassing of the cooling system is operating optimally almost all the time, thereby minimizing the risk of adverse effects due to air bubbles in the system. The incline can also be 10 to 80 degrees or 15 to 75 degrees, in order to take into account both upward and downward slopes.

[0025] According to another embodiment of the present invention, one or more flow-guiding members are arranged in the degassing chamber downstream of the coolant inlet and are configured to guide the coolant entering the degassing chamber via the coolant inlet substantially parallel to the longitudinal axis of the degassing chamber. The flow-guiding members direct the coolant flow in the expected migration direction of the bubbles in the degassing chamber, which promotes efficient separation of the bubbles in the degassing chamber.

[0026] According to another embodiment of the present invention, the degassing chamber includes at least one further coolant inlet connected to an associated further supply pipe of the cooling circuit so as to allow coolant circulating in the cooling circuit to flow from the further supply pipe into the degassing chamber via the associated further coolant inlet. The cross-sectional dimensions of the degassing chamber are preferably larger than the cross-sectional dimensions of the further supply pipe, thereby allowing air bubbles entrained with the coolant flowing through the further supply pipe to enter the degassing chamber via the associated further coolant inlet and subsequently migrate within the degassing chamber to the second coolant outlet. The further coolant inlet is located relative to the first and second coolant outlets such that coolant flow within the degassing chamber between the further coolant inlet and the first coolant outlet moves these migrating air bubbles in the longitudinal direction of the degassing chamber toward the second coolant outlet. As a result, air bubbles delivered to the degassing chamber can be efficiently separated from the coolant within the degassing chamber, along with the coolant from the further supply pipe.

[0027] When the cooling system is mounted on a vehicle and the vehicle is positioned in an upright use position on a horizontal surface, the first coolant outlet can be arranged at a higher position relative to the local gravity vector gv than the other coolant inlet. The advantages associated with this configuration have been discussed above with respect to the coolant inlet and the first coolant outlet, and therefore, for the sake of brevity, will not be repeated here.

[0028] Another embodiment of the present invention is characterized in that:

[0029] the cooling circuit and the coolant pump constitute a first cooling circuit and a first coolant pump of the cooling system, wherein the cooling system includes a second cooling circuit and a second coolant pump for circulating coolant in the second cooling circuit; and

[0030] The degassing chamber is provided with:

[0031] another coolant inlet connected to the supply pipe of the second cooling circuit so as to allow the coolant circulating in the second cooling circuit to flow from the supply pipe into the degassing chamber via the another coolant inlet, and

[0032] Another coolant outlet is connected to the second coolant pump so as to allow coolant to flow from the degassing chamber to the second coolant pump via the other coolant outlet.

[0033] In this case, a degassing chamber can be used to separate gas bubbles from the coolant circulating in two different cooling circuits.

[0034] According to another embodiment of the present invention, the cross-sectional dimensions of the degassing chamber are larger than the cross-sectional dimensions of the supply pipe of the second cooling circuit, thereby allowing bubbles entrained with the coolant flowing through the supply pipe to enter the degassing chamber via the associated additional coolant inlet and subsequently migrate within the degassing chamber to the second coolant outlet. The additional coolant inlet is located relative to the second coolant outlet and the additional coolant outlet so that the coolant flow in the degassing chamber between the additional coolant inlet and the additional coolant outlet will move these migrating bubbles in the longitudinal direction of the degassing chamber toward the second coolant outlet. As a result, bubbles delivered to the degassing chamber can also be efficiently separated from the coolant in the degassing chamber along with the coolant from the supply pipe of the second cooling circuit. The number of cooling circuits connected to the degassing chamber of the degassing device may also be three or more.

[0035] When the cooling system is mounted on a vehicle and the vehicle is positioned in an upright use position on a horizontal surface, the second coolant outlet can be arranged at a higher position relative to the local gravity vector gv than the other coolant inlet. The advantages associated with this configuration have been discussed above with respect to the coolant inlet and the first coolant outlet, and therefore, for the sake of brevity, will not be repeated here.

[0036] According to another embodiment of the invention, the static line has a lower end and an upper end, wherein the static line is connected to the degassing device at its lower end, and wherein:

[0037] The static line slopes upward along its entire length from its lower end to its upper end, or

[0038] The static pipeline consists of a number of interconnected length sections arranged in series with one another and formed by one or more first length sections and one or more horizontal second length sections, each of the one or more first length sections being inclined upward when viewed in a direction along the static pipeline from its lower end towards its upper end.

[0039] Thus, the static line lacks a downwardly sloping section which could prevent gas bubbles from migrating from the degasser towards the expansion tank.

[0040] Further advantageous features of the cooling system according to the invention will emerge from the following description.

[0041] The invention also relates to a vehicle having the features defined in this application.

[0042] Further advantageous features of the vehicle according to the invention will emerge from the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] With reference to the accompanying drawings, the following is a detailed description of an embodiment of the present invention cited as an example. In the accompanying drawings:

[0044] Figure 1 is a schematic diagram of a cooling system according to a first embodiment of the present invention,

[0045] Figure 2 is a schematic diagram of a cooling system according to a second embodiment of the present invention,

[0046] Figure 3 is a schematic diagram of a cooling system according to a third embodiment of the present invention,

[0047] Figure 4 is a schematic diagram of a cooling system according to a fourth embodiment of the present invention,

[0048] Figure 5 is through Figure 1 Schematic vertical section of a degassing device included in a cooling system of

[0049] Figure 6 is a schematic vertical section through a degassing device according to an alternative variant, and

[0050] Figure 7 is a schematic vertical section through a degassing device according to another variant. DETAILED DESCRIPTION

[0051] Figure 1 A cooling system 1 according to an embodiment of the present invention is shown very schematically in FIG. The cooling system 1 comprises a cooling circuit 10 for cooling at least one component 11 by means of a coolant circulating in the cooling circuit. The coolant flowing through the cooling circuit 10 is preferably water, possibly with an antifreeze additive, such as ethylene glycol. A coolant pump 12, preferably in the form of an electrically driven pump, is arranged in the cooling circuit 10 in order to circulate the coolant in the cooling circuit. The cooling system 1 may further comprise an electronic control unit 2, which is connected to the coolant pump 12 and is configured to control its operation in order to thereby control the flow rate of the coolant circulating in the cooling circuit 10.

[0052] Furthermore, a cooling device 13, such as in the form of a heat exchanger, is provided in the cooling circuit 10 to remove heat from the coolant circulating therein. The cooling system 1 can be used, for example, in a motor vehicle 3, such as a hybrid or fully electric vehicle, in which case the cooling device 13 can be in the form of a radiator, such as a conventional coolant radiator. In this case, the cooling circuit 10 can be a cooling circuit for cooling a vehicle component 11, such as an electrical energy storage device (e.g., a battery or a bank of batteries), for supplying electrical energy to the vehicle's electric traction motor, or a cooling circuit for cooling a vehicle component, such as a power electronics device (e.g., an inverter and a DC converter), for controlling the flow of electrical power between an electrical energy storage device of the aforementioned type and the electric traction motor. The coolant flowing through the radiator 13 is cooled by ambient air, which is blown toward the radiator when the vehicle 3 is in motion. The vehicle 3 can also be provided with a fan (not shown), which can be operated when necessary to generate an air flow through the radiator 13.

[0053] The cooling system 1 includes an expansion tank 30, which is provided with an expansion chamber 31 for accumulating coolant, wherein the expansion chamber 31 is surrounded by an outer shell 32 of the expansion tank. The expansion tank 30 is provided with a closable refill opening 33, which is arranged in the upper part of the shell 32. Coolant can be introduced into the expansion chamber 31 via the refill opening 33 to provide replenishment of the cooling system.

[0054] The refill opening 33 is closed by means of a removable cover 34. Furthermore, the expansion tank 31 is provided with a valve arrangement (not shown), which comprises a pressure relief valve for limiting the pressure in the expansion chamber 31 and a return valve. The valve arrangement can be arranged in the cover 34 or in the housing 32. When the pressure in the expansion chamber exceeds the pressure level given by the pressure relief valve due to an increase in the coolant volume, the pressure relief valve allows air and coolant to flow out of the upper part of the expansion chamber 31. Thus, the pressure relief valve ensures that the pressure in the expansion chamber 31 cannot exceed a predetermined pressure level. When the pressure in the expansion chamber becomes lower than the pressure level given by the return valve due to a decrease in the coolant volume, the return valve allows air to flow from the surrounding environment into the upper part of the expansion chamber 31.

[0055] The expansion chamber 31 is connected to the cooling circuit 10 via a static line 5 so as to allow the expansion chamber 31 to receive coolant from the cooling circuit 10 .

[0056] The cooling system 1 includes a degassing device 40, which is arranged in the cooling circuit 10 for separating air bubbles from the coolant circulating in the cooling circuit, wherein the degassing device 40 is located at a lower position than the expansion tank 30 and is connected to the expansion chamber 31 of the expansion tank 30 via the static line 5 so as to allow the air bubbles separated from the coolant in the degassing device 40 to migrate upward in the static line 5 toward the expansion chamber 31. Figure 1 In the embodiment shown, the static line 5 is connected directly to the expansion chamber 31 via an opening 35 provided in the housing 32 of the expansion tank.

[0057] The static line 5 has a lower end 5a and an upper end 5b, wherein the static line 5 is connected to the degassing device 40 at its lower end 5a. Figure 1 In the embodiment shown, the static line 5 is inclined upwards along its entire length from its lower end 5a to its upper end 5b. Figure 2 As shown in , as an alternative, the static pipeline 5 may consist of a combination of one or more first length sections 6a and one or more horizontal second length sections 6b, each of the one or more first length sections being inclined upward when viewed in a direction along the static pipeline from its lower end towards its upper end, wherein these first length sections 6a and second length sections 6b are interconnected and arranged in series with each other.

[0058] The degassing device 40 includes a degassing chamber 41 (see Figure 5 ), the degassing chamber is surrounded by a housing 42 and has:

[0059] a coolant inlet 43 connected to the supply pipe 15 of the cooling circuit 10 so as to allow the coolant circulating in the cooling circuit to flow from the supply pipe 15 into the degassing chamber 41 via this coolant inlet 43 ;

[0060] A first coolant outlet 44 is connected to the coolant pump 12 to allow coolant to flow from the degassing chamber 41 to the coolant pump 12 via the first coolant outlet 44 , wherein

[0061] The coolant inlet 43 and the first coolant outlet 44 are spaced apart from each other in the longitudinal direction of the degassing chamber 41 ; and

[0062] a second coolant outlet 45 which is connected to the expansion chamber 31 via the static line 5 and which is located at a higher position relative to the local gravity vector gv than the first coolant outlet 44 when the cooling system is mounted to the vehicle and the vehicle is positioned in an upright use position on a horizontal surface.

[0063] The second coolant outlet 45 is located in the upper part of the degassing chamber 41 in order to allow gas bubbles that have migrated to the upper part of the degassing chamber to leave the degassing chamber via the second coolant outlet 45 and enter the static line 5. The gas bubbles can be separated here from the coolant in the cooling circuit 10. The second coolant outlet 45 is preferably located at the highest point in the degassing chamber 41, but as an alternative, it can be located slightly below the highest point in the degassing chamber 41.

[0064] The cross-sectional dimensions of the degassing chamber 41 are larger than the cross-sectional dimensions of the supply pipe 15, so that the flow rate of the coolant in the degassing chamber 41 is lower than the flow rate of the coolant in the supply pipe 15 leading to the degassing chamber, thereby allowing air bubbles to be carried along with the relatively fast coolant flow in the supply pipe 15 and enter the degassing chamber 41 through the coolant inlet 43, and then migrate to the second coolant outlet 45 in the degassing chamber 41. The slower coolant flow in the degassing chamber 41 will increase the residence time of the coolant in the degassing chamber, which in turn will give the air bubbles in the coolant an opportunity to migrate to the second coolant outlet 45 in the degassing chamber 41.

[0065] The cross-sectional dimensions of the degassing chamber 41 are preferably much larger than the cross-sectional dimensions of the supply pipe 15, so that the relationship between the flow rate v1 of the coolant flowing through the degassing chamber 41 and the flow rate v2 of the coolant flowing through the supply pipe 15 between the coolant inlet 43 and the first coolant outlet 44 is 1:2 or lower, preferably 1:3 or lower.

[0066] The degassing chamber 41 may have a cylindrical shape, for example a circular cylindrical shape, but alternatively it may have any other suitable shape.

[0067] The electronic control unit 2 may be configured to control the coolant pump 12 in such a way that the flow rate of the coolant circulating through the cooling circuit 10 is maintained during normal operating conditions at a value that allows continuous degassing of the coolant in the cooling circuit during normal operating conditions. However, as an alternative, the electronic control unit 2 may be configured to control the coolant pump 12 in such a way that the flow rate is set intermittently or only in specific cases to a value suitable for efficient degassing of the coolant in the cooling circuit 10.

[0068] The second coolant outlet 45 is located relative to the coolant inlet 43 and the first coolant outlet 44 such that the coolant flow between the coolant inlet 43 and the first coolant outlet 44 in the degassing chamber 41 will move the migrating bubbles in the degassing chamber 41 toward the second coolant outlet 45 in the longitudinal direction of the degassing chamber 41. Therefore, the migration direction of the bubbles in the degassing chamber 41 corresponds to the flow direction of the coolant in the degassing chamber, and the coolant flow in the degassing chamber 41 will thereby promote the movement of the bubbles toward the second coolant outlet 45.

[0069] When the cooling system is mounted on a vehicle and the vehicle is positioned in an upright use position on a horizontal surface, the first coolant outlet 44 is arranged at a higher position relative to the local gravity vector gv than the coolant inlet 43. As a result, the coolant flow from the coolant inlet 43 will have a vector component opposite to the local gravity vector gv, and will thereby cause the air bubbles to have a flow vector component in an upward direction, which will further promote the movement of the air bubbles toward the second coolant outlet 45.

[0070] exist Figure 1 In the embodiment shown, the degassing chamber 41 has an elongated shape and is arranged with its longitudinal axis 46 extending in the vertical direction. In this case, the above-mentioned flow direction of the coolant in the degassing chamber 41 is achieved by locating the coolant inlet 43 at a lower position than the first coolant outlet 44, which results in an upward coolant flow in the degassing chamber 41. However, as an alternative, the degassing chamber 41 may be arranged with its longitudinal axis 46 inclined at an angle α of 0-90° relative to the horizontal plane, for example, at an angle α of >0° and <=90°, or at an angle between 10-90° or 15-90°. When the degassing chamber 41 is arranged with its longitudinal axis 46, for example, at Figure 2 When inclined in the manner shown, air bubbles can rise in the degassing chamber 41 and hit the inclined upper wall surface 47 in the degassing chamber, so that under the effect of the coolant flow between the coolant inlet 43 and the first coolant outlet 44 in the degassing chamber 41, the air bubbles will be transported along this wall surface 47 towards the second coolant outlet 45.

[0071] One or more flow guide members 48, 49 (see Figure 6 and 7 ) can be arranged downstream of the coolant inlet 43 in the degassing chamber 41 and is configured to guide the coolant entering the degassing chamber 41 via the coolant inlet 43 substantially parallel to the longitudinal axis 46 of the degassing chamber. Such a flow-guiding member can, for example, be in the form of a guide plate 46 or similar device arranged in front of the coolant inlet 43 in order to deflect the incoming coolant flow into a direction substantially parallel to the longitudinal axis 46 of the degassing chamber 41, such as Figure 6 As shown. Figure 7 As shown, the flow guide member may alternatively be in the form of a perforated plate 49 or the like arranged across the degassing chamber 41 .

[0072] exist Figure 3 In the embodiment shown, the cooling system 1 comprises a degassing device 40 having a degassing chamber 41 having the Figure 1The coolant inlet 43, which is connected to the first supply pipe 15 of the cooling circuit 10, and the first coolant outlet 44 and the second coolant outlet 45 are arranged in the manner described. In this case, the degassing chamber 41 also includes a further coolant inlet 43a, which is connected to the associated second supply pipe 15a of the cooling circuit 10, so as to allow the coolant circulating in the cooling circuit to flow from this second supply pipe 15a into the degassing chamber 41 via the associated further coolant inlet 43a. In the example shown, the cooling circuit 10 includes a valve device 16 for controlling the coolant flow toward the first supply pipe 15 and the second supply pipe 15a.

[0073] The cross-sectional dimensions of the degassing chamber 41 are larger than those of the first supply pipe 15, thereby allowing air bubbles entrained with the coolant flowing through the first supply pipe 15 to enter the degassing chamber 41 via the associated coolant inlet 43 and subsequently migrate within the degassing chamber 41 to the second coolant outlet 45. The cross-sectional dimensions of the degassing chamber 41 are preferably substantially larger than those of the first supply pipe 15, such that when the valve device 16 directs the entire coolant flow in the cooling circuit 10 to the first supply pipe 15, the relationship between the flow rate v1 of the coolant flowing through the degassing chamber 41 and the flow rate v2 of the coolant flowing through the first supply pipe 15 between the coolant inlet 43 and the first coolant outlet 44 is 1:2 or less, preferably 1:3 or less. In this case, the electronic control unit 2 can be configured to control the valve device 16 to direct the entire coolant flow in the cooling circuit 10 to the first supply pipe 15 when the coolant in the cooling circuit 10 is to undergo efficient degassing in the degassing chamber 41.

[0074] exist Figure 3 In the illustrated embodiment, the cross-sectional dimensions of the degassing chamber 41 are also larger than the cross-sectional dimensions of the second supply tube 15 a, thereby allowing air bubbles carried along with the coolant flowing through the second supply tube 15 a to enter the degassing chamber 41 via the associated coolant inlet 43 a and subsequently migrate to the second coolant outlet 45 in the degassing chamber 41, wherein the coolant inlet 43 a is located at such a position relative to the first coolant outlet 44 and the second coolant outlet 45 that the coolant flow in the degassing chamber 41 between the coolant inlet 43 a and the first coolant outlet 44 will move these migrating air bubbles in the longitudinal direction of the degassing chamber 41 toward the second coolant outlet 45.

[0075] When the cooling system is mounted on a vehicle and the vehicle is positioned in an upright position for use on a horizontal surface, the first coolant outlet 44 is positioned at a higher position relative to the local gravity vector gv than the coolant inlet 43a. As a result, the coolant flow from the coolant inlet 43a has a vector component opposite to the local gravity vector gv, and thus, the air bubbles have a flow vector component in an upward direction, which further encourages the bubbles to move toward the second coolant outlet 45.

[0076] exist Figure 4 In the illustrated embodiment, a cooling system 1 includes a first cooling circuit 10 for cooling at least one first component 11 with coolant circulating therein, and a second cooling circuit 20 for cooling at least one second component 21 with coolant circulating therein. A first coolant pump 12 is provided in the first cooling circuit 10 to circulate the coolant therein, and a second coolant pump 22 is provided in the second cooling circuit 20 to circulate the coolant therein. The first coolant pump 12 and the second coolant pump 22 are preferably electrically driven pumps. An electronic control unit 2 is connected to the coolant pumps 12 and 22 and is configured to control their operation, thereby controlling the flow rate of the coolant circulating in the first cooling circuit 10 and the second cooling circuit 20. A cooling device 13 and 23, such as a radiator or any other suitable type of heat exchanger, may be provided in each cooling circuit 10 and 20 to remove heat from the coolant circulating therein.

[0077] exist Figure 4 In the embodiment shown, the cooling system 1 comprises a degassing device 40 having a degassing chamber 41 having the Figure 1 The coolant inlet 43 and the first coolant outlet 44 and the second coolant outlet 45 are arranged in the manner described, wherein the coolant inlet 43 is connected to the supply pipe 15 of the first cooling circuit 10, and the coolant outlet 44 is connected to the first coolant pump 12 so as to allow the coolant circulating in the first cooling circuit 10 to flow from the supply pipe 15 into the degassing chamber 41 via the coolant inlet 43, and to allow the coolant to flow from the degassing chamber 41 to the first coolant pump 12 via the coolant outlet 44. In this case, the degassing chamber 41 further includes another coolant inlet 43b connected to the supply pipe 25 of the second cooling circuit 20 and another coolant outlet 44b connected to the second coolant pump 22 so as to allow the coolant circulating in the second cooling circuit 20 to flow from the supply pipe 25 into the degassing chamber 41 via the another coolant inlet 43b, and to allow the coolant to flow from the degassing chamber 41 to the second coolant pump 22 via the another coolant outlet 44b.

[0078] The cross-sectional dimensions of the degassing chamber 41 are larger than the cross-sectional dimensions of the supply pipe 15 of the first cooling circuit 10, thereby allowing air bubbles entrained with the coolant flowing through the supply pipe 15 to enter the degassing chamber 41 via the associated coolant inlet 43 and subsequently migrate within the degassing chamber 41 to the second coolant outlet 45. The cross-sectional dimensions of the degassing chamber 41 are preferably much larger than the cross-sectional dimensions of the supply pipe 15 of the first cooling circuit 10, so that when the first coolant pump 12 is in operation and the second coolant pump 22 is off, the relationship between the flow rate v1 of the coolant flowing through the degassing chamber 41 between the coolant inlet 43 and the first coolant outlet 44 and the flow rate v2 of the coolant flowing through the supply pipe 15 is 1:2 or lower, preferably 1:3 or lower.

[0079] exist Figure 4 In the embodiment shown, the cross-sectional dimensions of the degassing chamber 41 are also larger than the cross-sectional dimensions of the supply pipe 25 of the second cooling circuit 20, thereby allowing air bubbles carried along with the coolant flowing through the supply pipe 25 to enter the degassing chamber 41 via the associated further coolant inlet 43 b and subsequently migrate in the degassing chamber 41 to the second coolant outlet 45, wherein the further coolant inlet 43 b is located at such a position relative to the second coolant outlet 45 and the further coolant outlet 44 b that the coolant flow in the degassing chamber between the further coolant inlet 43 b and the further coolant outlet 44 b will move these migrating air bubbles in the longitudinal direction of the degassing chamber 41 toward the second coolant outlet 45.

[0080] When the cooling system is mounted on a vehicle and the vehicle is positioned in an upright position for use on a horizontal surface, the further coolant outlet 44b is arranged at a higher position relative to the local gravity vector gv than the further coolant inlet 43b. As a result, the coolant flow from the coolant inlet 43b toward the coolant outlet 44b will have a vector component opposite to the local gravity vector gv, thereby causing the air bubbles to have a flow vector component in an upward direction, which will further promote the movement of the air bubbles toward the second coolant outlet 45.

[0081] Of course, it is also possible to connect more than two cooling circuits to the same degassing device 40 of the type described above.

[0082] Of course, the present invention is by no means limited to the embodiments described above. On the contrary, many possibilities for its modification will be apparent to those skilled in the art without departing from the basic concept of the invention as defined in the appended claims.

Claims

1. A cooling system comprising: Cooling circuit (10); a coolant pump (12) for circulating the coolant in the cooling circuit (10); an expansion tank (30) for accumulating coolant; and a degassing device (40) arranged in the cooling circuit (10) for separating gas bubbles from the coolant circulating in the cooling circuit (10), wherein the degassing device (40) is connected to the expansion tank (30) via a static line (5) and comprises a degassing chamber (41), The degassing chamber has: A coolant inlet (43) connected to a supply pipe of the cooling circuit (10) to allow the coolant circulating in the cooling circuit (10) to pass through the A coolant inlet (43) flows from the supply pipe into the degassing chamber (41), a first coolant outlet (44) connected to the coolant pump (12) so as to allow coolant to flow from the degassing chamber (41) to the coolant pump (12) via the first coolant outlet (44), wherein the coolant inlet (43) and the first coolant outlet (44) are spaced apart from each other in a longitudinal direction of the degassing chamber (41), and a second coolant outlet (45) connected to the expansion tank (30) via the static line (5) and located at a higher position relative to the local gravity vector gv than the first coolant outlet (44) when the cooling system is mounted to a vehicle and the vehicle is positioned in an upright use position on a horizontal surface, wherein the cross-sectional dimension of the degassing chamber (41) is larger than the cross-sectional dimension of the supply pipe, thereby allowing bubbles carried along with the coolant flowing through the supply pipe to enter the degassing chamber (41) through the coolant inlet (43) and then migrate to the second coolant outlet (45) in the degassing chamber (41), wherein the second coolant outlet (45) is located relative to the coolant inlet (43) and the first coolant outlet (44) such that coolant flow in the degassing chamber (41) between the coolant inlet (43) and the first coolant outlet (44) will move migrating bubbles in the longitudinal direction of the degassing chamber (41) toward the second coolant outlet (45), wherein the first coolant outlet (44) is arranged at a higher position relative to the local gravity vector gv than the coolant inlet (43) when the cooling system is mounted to a vehicle and the vehicle is positioned in an upright use position on a horizontal surface, and The degassing chamber (41) has an elongated shape and is arranged so that its longitudinal axis (46) is inclined at an angle (α) in the range of 0-90° relative to a horizontal plane when the cooling system is mounted to a vehicle and the vehicle is positioned in an upright use position.

2. The cooling system according to claim 1, wherein: The degassing chamber (41) is arranged such that its longitudinal axis (46) is inclined at an angle (α) in the range 10°-90° relative to a horizontal plane when the cooling system is mounted to a vehicle and the vehicle is positioned in an upright use position.

3. The cooling system according to claim 1, wherein: The degassing chamber (41) is arranged such that its longitudinal axis (46) is inclined at an angle (α) in the range 15°-90° relative to a horizontal plane when the cooling system is mounted to a vehicle and the vehicle is positioned in an upright use position.

4. The cooling system according to any one of claims 1 to 3, wherein: The cross-sectional size of the degassing chamber (41) is larger than the cross-sectional size of the supply pipe, so that the relationship between the flow rate (v1) of the coolant flowing through the degassing chamber (41) and the flow rate (v2) of the coolant flowing through the supply pipe between the coolant inlet (43) and the first coolant outlet (44) is 1:2 or less.

5. The cooling system according to any one of claims 1 to 3, wherein: The cross-sectional size of the degassing chamber (41) is larger than the cross-sectional size of the supply pipe, so that the relationship between the flow rate (v1) of the coolant flowing through the degassing chamber (41) and the flow rate (v2) of the coolant flowing through the supply pipe between the coolant inlet (43) and the first coolant outlet (44) is 1:3 or less.

6. The cooling system according to any one of claims 1 to 3, wherein: The coolant inlet (43) is located at a lower position than the first coolant outlet and the second coolant outlet.

7. The cooling system according to any one of claims 1 to 3, wherein: One or more flow guide members (48, 49) are arranged in the degassing chamber (41) downstream of the coolant inlet (43) and are configured to guide the coolant entering the degassing chamber (41) through the coolant inlet (43) substantially parallel to the longitudinal axis (46) of the degassing chamber.

8. The cooling system according to any one of claims 1 to 3, wherein: The cooling system (1) includes a radiator (13) for cooling the coolant circulating in the cooling circuit (10).

9. The cooling system according to any one of claims 1 to 3, wherein: The degassing chamber (41) comprises at least one further coolant inlet connected to an associated further supply pipe (15a) of the cooling circuit (10) so as to allow the coolant circulating in the cooling circuit (10) to flow from the further supply pipe (15a) into the degassing chamber (41) via the associated further coolant inlet.

10. The cooling system according to claim 9, wherein: The cross-sectional dimensions of the degassing chamber (41) are larger than the cross-sectional dimensions of the further supply tube (15a), thereby allowing air bubbles carried along with the coolant flowing through the further supply tube (15a) to enter the degassing chamber (41) via the associated further coolant inlet and subsequently migrate to the second coolant outlet (45) in the degassing chamber (41), wherein the further coolant inlet is located at such a position relative to the first coolant outlet and the second coolant outlet that the coolant flow in the degassing chamber (41) between the further coolant inlet and the first coolant outlet (44) will move these migrating air bubbles in the longitudinal direction of the degassing chamber (41) toward the second coolant outlet (45).

11. The cooling system according to any one of claims 1 to 3, wherein: The cooling circuit (10) and the coolant pump (12) constitute a first cooling circuit and a first coolant pump of the cooling system (1), wherein the cooling system (1) includes a second cooling circuit (20) and a second coolant pump (22) for circulating the coolant in the second cooling circuit (20); and The degassing chamber (41) is provided with: another coolant inlet connected to a supply pipe of the second cooling circuit (20) so as to allow the coolant circulating in the second cooling circuit (20) to flow from the supply pipe into the degassing chamber (41) via the another coolant inlet, and Another coolant outlet (44b) connected to the second coolant pump (22) so as to allow coolant to flow from the degassing chamber (41) to the second coolant pump (22) via the other coolant outlet (44b).

12. The cooling system according to claim 11, wherein: The cross-sectional dimensions of the degassing chamber (41) are larger than the cross-sectional dimensions of the supply pipe of the second cooling circuit (20), thereby allowing air bubbles carried along with the coolant flowing through the supply pipe to enter the degassing chamber (41) via the associated further coolant inlet and subsequently migrate to the second coolant outlet (45) in the degassing chamber (41), wherein the further coolant inlet is located at such a position relative to the second coolant outlet (45) and the further coolant outlet (44b) that the coolant flow in the degassing chamber (41) between the further coolant inlet and the further coolant outlet (44b) will move these migrating air bubbles in the longitudinal direction of the degassing chamber (41) toward the second coolant outlet (45).

13. The cooling system according to any one of claims 1 to 3, wherein: The static line (5) has a lower end (5a) and an upper end (5b), wherein the static line (5) is connected to the degassing device (40) at its lower end (5a), and wherein: - the static line is inclined upwards along its entire length from its lower end (5a) to its upper end (5b), or - the static pipeline (5) consists of several interconnected length sections arranged in series with one another and formed by one or more first length sections (6a) and one or more horizontal second length sections (6b), each of the one or more first length sections being inclined upwards when viewed in a direction along the static pipeline from its lower end towards its upper end.

14. A vehicle, wherein The vehicle (3) comprises a cooling system (1) according to any one of claims 1-13.

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