System for supplying an operating fluid in a motor vehicle

Abstract

System (1) for providing an operating fluid in a motor vehicle (2) comprising a tank (3) in which the operating fluid can be stored and a dispensing point (4) at which the operating fluid can be provided, further comprising a bidirectionally operable pump (9) for pumping the operating fluid, functionally arranged between the tank (3) and the dispensing point (4), and further comprising a suction line (15) and a return line (16), which functionally are arranged parallel to each other between the pump (9) and the tank (3), wherein the operating fluid can be pumped back to the tank (3) via the return line (16) past the suction line (15), wherein a shut-off valve (6) is arranged in the return line (16), which is designed as a beak valve (27) and which prevents the suction of operating fluid from the tank (3) via the return line (16).

Description

[0001] The supply of operating fluids in a motor vehicle is necessary for many of its functions. The most important operating fluid in a motor vehicle today is usually the fuel for an internal combustion engine. Other operating fluids are used, for example, for the operation of the exhaust system of the internal combustion engine, such as urea-water solutions for selective catalytic reduction, or for optimizing the energy conversion process in the internal combustion engine, such as water or a water-alcohol mixture to improve the performance of the internal combustion engine, exhaust emissions, and / or fuel consumption.

[0002] When using water as the operating fluid, and depending on the mixing ratio also when using water-alcohol mixtures, it may be necessary to protect a system for supplying the operating fluid from freezing when the vehicle is parked, in order to avoid damage to the system.

[0003] It is known, for example, to remove the operating fluid from the system, particularly from the system's pipes, by pumping the operating fluid back from a system dispensing point into a system tank. A return line can be provided for such return pumping, as well as for pumping back excess operating fluid. Generally, it is desirable that, during normal operation of the pump supplying the operating fluid to the dispensing point, the intake of operating fluid via such a return line be prevented.

[0004] German patent applications DE 10 2019 201 144 A1 and DE 10 2015 208 509 A1 each disclose a system in which a ball check valve is used to prevent the intake of operating fluid via the return line. However, a disadvantage of such a ball check valve is that a certain spring preload is required to keep the ball check valve closed. This preload must then be overcome during return pump operation to allow operating fluid to be pumped back to the tank. Overcoming this initial preload has proven problematic in practice.

[0005] Starting from this premise, the object of the present invention is to at least partially solve the problem described with reference to the prior art. This object is achieved by the system according to the features of independent claim 1.

[0006] Further advantageous embodiments are specified in the dependent claims, as well as in the description and, in particular, in the description of the figures. It should be noted that a person skilled in the art can combine the individual features in a technologically meaningful way and thereby arrive at further embodiments of the invention.

[0007] This document describes a system for supplying an operating fluid in a motor vehicle, comprising a tank in which the operating fluid can be stored and a dispensing point at which the operating fluid can be supplied, further comprising a bidirectionally operable pump for supplying the operating fluid, functionally arranged between the tank and the dispensing point, and further comprising a suction line and a return line, which functionally arranged parallel to each other between the pump and the tank, wherein the operating fluid can be returned to the tank via the return line past the suction line, wherein a shut-off valve, designed as a beak valve, is arranged in the return line and prevents the suction of operating fluid from the tank via the return line.

[0008] With the nozzle valve provided according to the invention, an initial overcoming of a spring preload force is unnecessary in the return operation of the pump. During suction operation, the nozzle valve closes essentially without force and is increasingly closed by the pressure differential acting before and after the nozzle valve. When the pressure differential reverses during return operation, the nozzle valve opens similarly with essentially no force.

[0009] The beak valve has a section resembling a duck's bill, in which a wall tapers from an inlet to an outlet, with flattened side walls abutting each other at the outlet when the beak valve is closed. Such a beak valve is known, for example, from DE 10 2008 006 686 A1. The flattened side walls can be pre-tensioned against each other, with the pre-tension being determined in particular by the material of the beak valve and the geometry of the section described above. When designing the beak valve, it is preferably important to ensure that such a pre-tension is low compared to the spring pre-tension required in a ball check valve known from the prior art.

[0010] In the inlet area, the nozzle valve preferably has a circular cross-section. Furthermore, the nozzle valve may have a flange in this area for mounting it in a pipe.

[0011] The beak valve is arranged in the return line in such a way that it allows operating fluid to be pumped back to the tank, with the "duckbill" of the beak valve functionally pointing towards the tank.

[0012] The beak valve is made of an elastic material, preferably an elastic plastic containing, for example, silicone, or an elastic natural material containing, for example, natural rubber. Such an elastic material ensures that the "duckbill" of the beak valve remains securely closed even at low suction pressure, thus preventing the intake of operating fluid from the tank via the return line. Furthermore, such a material is corrosion-resistant.

[0013] In the context of the invention, "functionally" means that the arrangement of the system components, or the relationship between two or more system components, does not necessarily have to be spatially or geometrically defined. For example, in the context of the invention, the suction line does not have to be spatially or geometrically parallel to the return line. Rather, it means that the return line can be used for pumping the operating fluid independently of the suction line, and vice versa. The term "arranged parallel to each other" is therefore to be understood in the context of the invention as the opposite of "arranged in series".

[0014] The suction line and the return line can merge into a single line in the area of ​​the tank and / or in the area of ​​the pump. Functionally speaking, at least one branch point can be provided between the pump and the tank where the return line branches off from the suction line or vice versa, or where both branch off from a third line.

[0015] The bidirectional pump can be used for metering the operating fluid in addition to pumping it. For this purpose, the pump is preferably driven by an electric motor. The pump is connected to the delivery point via at least one line. Additional system components, such as a valve and / or a sensor, can be provided on or in the line.

[0016] The system preferably has a sensor in or on the tank with which the fill level and / or properties, for example a temperature, of the operating fluid in the tank can be measured.

[0017] Preferably, the nozzle valve is designed such that a pressure loss generated by the nozzle valve during a return pump operation is smaller than a pressure loss generated by all other components in the return line.

[0018] In particular, the valve is designed such that the pressure loss is in the range of 20 to 30 kPa, preferably in the range of 22.5 to 27.5 kPa, and more preferably 25 kPa. The flow rate is in particular at least two liters per hour, preferably at least 2.5 liters per hour, and more preferably three liters per hour.

[0019] Such dimensioning of the valve is achieved in particular through the choice of material and the design of the geometry of the previously described section of the valve. The other components in the return line can be, for example, further valves or sensors.

[0020] It can be advantageously provided that a further shut-off valve, preferably designed as a ball check valve, is arranged in the return line in the return direction before or after the nozzle valve.

[0021] Such an additional shut-off valve is therefore preferably designed as a poppet valve and can be used, for example, when additional protection against the intake of operating fluid through the return line is desired. The additional shut-off valve can thus be considered as a supplement to the poppet valve.

[0022] When using a ball check valve, the spring preload force of the ball check valve can be smaller than that of ball check valves known from the prior art, due to the nozzle valve provided according to the invention.

[0023] It is also preferred if a shut-off valve is also arranged in the suction line, which is preferably designed as a ball check valve and which prevents the operating fluid from being pumped back to the tank via the suction line.

[0024] Such a shut-off valve in the suction line allows the operating fluid to be drawn from the tank. The shut-off valve is preferably designed as a poppet valve. However, it is also conceivable that the shut-off valve in the suction line is designed as a beak valve.

[0025] Furthermore, it is preferred if several of the shut-off valves are combined in one integral component.

[0026] Such an integral component preferably has a first connection connected to the feed pump, a second connection connected to the suction line, and a third connection connected to the return line. The integral component is then designed such that operating fluid is drawn in through the second connection and returned through the third connection.

[0027] The additional shut-off valve in the return line and the shut-off valve in the suction line can be functionally combined in an integral component, particularly in the form of a diverter valve. For this purpose, the integral component can be designed to include at least one movable valve element, for example, in the form of a ball, which performs the function of both shut-off valves. Such a movable valve element is moved by the flowing operating fluid, depending on the direction of flow, so that either the second or the third port of the valve is selectively closed. The integral component then acts as a kind of diverter valve for the suction line and the return line.

[0028] In a preferred embodiment, a first filter module is arranged on or in the intake line.

[0029] Functionally speaking, the first filter module is positioned between the tank and the pump and absorbs particles, such as deposits from the tank, from the operating fluid, primarily to protect the pump from these particles. The first filter module can comprise one or more filters, which may be designed as sieves and / or fabric filters.

[0030] If a previously described shut-off valve is provided in the suction line, the first filter module is preferably arranged behind the shut-off valve in the return direction so that the operating fluid does not reach the first filter module during return operation.

[0031] Preferably, a second filter module may be arranged at or in the delivery point or in or on a line between the delivery pump and the delivery point.

[0032] The second filter module serves primarily to absorb particles, such as pump abrasion from the feed pump, from the operating fluid and thereby protect the discharge point from these particles. This second filter module can comprise one or more filters, which may be designed as sieves and / or fabric filters.

[0033] Water is particularly preferred as the operating fluid.

[0034] The use of water as the operating fluid offers the advantage that the material of the beak valve does not need to be resistant to, for example, oil or acid.

[0035] The point of delivery is preferably a water injection unit on an internal combustion engine. By providing the water, the energy conversion process in the internal combustion engine can be optimized. In particular, the combustion temperature can be lowered by introducing the water, which can lead to an improvement in the performance of the internal combustion engine, the emission quality and / or fuel consumption.

[0036] As an alternative to water, mixtures with water and other substances are also possible, for example a water-alcohol mixture as an operating fluid, whereby ethanol and / or methanol are added to the water.

[0037] Furthermore, it is preferred if the system has a control unit with which the delivery pump can be controlled.

[0038] The control unit can be located outside the fuel pump and is preferably connected to the fuel pump via an electrical connection. This electrical connection can be a combined line for transmitting electrical power to operate the fuel pump and for transmitting data / control commands for its operation. The control unit may be a higher-level control unit of the vehicle, for example, an engine control unit of the internal combustion engine.

[0039] The control unit can be used, for example, to change the direction of flow. It can also be configured to adjust the flow rate of the operating fluid. Such an adjustment can be made based on sensor data from a sensor in the exhaust system of an internal combustion engine. Alternatively or additionally, the control unit can be configured to control an electric motor used to operate the fuel pump.

[0040] Furthermore, a motor vehicle with an internal combustion engine and a system according to the invention is described here, wherein the internal combustion engine has at least one intake manifold for supplying the internal combustion engine with air and at least one cylinder for combustion, wherein the discharge point of the system is arranged on or in the intake manifold and is equipped for discharging the operating fluid into the intake manifold or the discharge point is arranged on the cylinder and is equipped for discharging the operating fluid into the cylinder.

[0041] If the injection point is designed to deliver the operating fluid into the intake manifold, the injection method is also referred to as port injection and the injection point as a port injection unit. If the injection point is designed to deliver the operating fluid into the cylinder, the injection method is also referred to as direct injection and the injection point as a direct injection unit.

[0042] Port fuel injection requires lower pressure for delivering the operating fluid than direct injection, making it simpler and therefore more cost-effective to implement. However, direct injection offers greater design freedom in the described system.

[0043] It is conceivable that the system has two dispensing points, one of which is located on or in the suction pipe and is designed to dispense the operating fluid into the suction pipe, and another dispensing point is located on the cylinder and is designed to dispense the operating fluid into the cylinder.

[0044] The invention and its technical context are explained in more detail below with reference to the figures. The figures show preferred embodiments, to which the invention is not limited. It should be noted in particular that the figures, and especially the size relationships shown in the figures, are only schematic. They show: Fig. 1: a schematic representation of a first embodiment of a described system for providing an operating fluid in a motor vehicle; Fig. 2: a schematic representation of a second embodiment of a described system for providing an operating fluid in a motor vehicle; Fig. 3: a schematic representation of a third embodiment of a described system for providing an operating fluid in a motor vehicle; Fig. 4: a schematic representation of a fourth embodiment of a described system for providing an operating fluid in a motor vehicle; Fig. 5: a schematic representation of a fifth embodiment of a described system for providing an operating fluid in a motor vehicle; Fig. 6: a schematic representation of a sixth embodiment variant of a described system for providing an operating fluid in a motor vehicle; Fig. 7: a schematic representation of a seventh embodiment variant of a described system for providing an operating fluid in a motor vehicle; Fig. 8: a schematic representation of an eighth variant of the described system for providing an operating fluid in a motor vehicle; Fig. 9: a schematic representation of a first embodiment of a motor vehicle with the embodiment of the described system according to Fig. 1; and Fig. 10: a schematic representation of a second design variant of the motor vehicle with the design variant of the described system according to Fig. 1.

[0045] The Fig. Figures 1 to 8 show different design variants of a system 1 for providing an operating fluid in a motor vehicle 2.

[0046] System 1 has a tank 3 in which the operating fluid can be stored. System 1 also has a dispensing point 4 at which the operating fluid is dispensed to a consumer, in particular to an intake manifold 29 or a cylinder 30 of an internal combustion engine 28 (see Fig. 9 and Fig. 10), is available.

[0047] System 1 also includes a bidirectionally operable pump 9, which can draw the operating fluid from tank 3 and pump it to the dispensing point 4, where it can be metered if necessary, and can also pump it back from the dispensing point 4 to tank 3. Functionally, the pump 9 is located between tank 3 and the dispensing point 4 and is connected to the dispensing point 4 via a line 8.

[0048] The operating fluid can be drawn from the tank 3 via a suction line 15 which is functionally arranged between the feed pump 9 and the tank 3.

[0049] Operating fluid can be returned to tank 3 via a return line 16, which is functionally arranged between the feed pump 9 and the tank 3. A shut-off valve 6, designed as a poppet valve 27, is arranged in the return line 16 and prevents the operating fluid from being drawn in through the return line 16.

[0050] Compared to Fig. 1 is in the execution variant of system 1 according to Fig. 2 next to the beak valve 27 in the return line 16 a shut-off valve 6 designed as a ball check valve 7 is arranged, which is intended to support the beak valve 27 in preventing the suction of the operating fluid through the return line 16.

[0051] In the implementation variant of system 1 according to Fig. 3 is in comparison to the version variant in Fig. 1 in the suction line 15 a shut-off valve 6 designed as a ball check valve 7 is arranged, which prevents the operating fluid from being pumped back through the suction line 15.

[0052] In the implementation variant of system 1 according to Fig. 4 is in comparison to the version variant in Fig. 1 in the intake line 15 a first filter module 17 is arranged, with which particles are filtered from the operating fluid conveyed through the intake line 15.

[0053] In the implementation variant of system 1 according to Fig. 5 is in comparison to the version variant in Fig. 1 in line 8, i.e. functionally considered between the feed pump 9 and the discharge point 4, a second filter module 26 is arranged, with which particles are filtered from the operating fluid conveyed through line 8.

[0054] The implementation variant of system 1 according to Fig. 6 includes the implementation variants according to Fig. The system includes 3 to 5 additional components, namely the first filter module 17 and the check valve 6, designed as a ball check valve 7, in the suction line 15, as well as the second filter module 26 in the line 8. Furthermore, the system 1 has a control unit 21, which monitors and controls the delivery and / or metering of the operating fluid by the feed pump 9. Such a control unit 21 can, of course, also be provided in other design variants. The control unit 21 is connected to the feed pump 9 via an electrical connection 22. The electrical connection 22 can be designed as a combined line for transmitting electrical energy to operate the feed pump 9 and for transmitting data / control commands for the operation of the feed pump 9.

[0055] The implementation variant of system 1 according to Fig. 7 shows, in comparison to the one in Fig. In the embodiment shown in 6, next to the beak valve 27 in the return line 16, a shut-off valve 6 designed as a ball check valve 7 is installed.

[0056] In the implementation variant of system 1 according to Fig. 8 are compared to the one in Fig. In the embodiment shown in Figure 7, the two check valves 6, designed as ball check valves 7, are combined in an integral component 11. The integral component 11 has a first port 12, to which the feed pump 9 is connected, a second port 13, to which the suction line 15 is connected, and a third port 14, to which the return line 16 is connected. Operating fluid is drawn in through the second port 13 and returned through the third port 14. The check valves 6 can be functionally combined in the integral component 11, particularly in the form of a shuttle valve.

[0057] The Fig. 9 and Fig. Figure 10 shows a motor vehicle 2 with an internal combustion engine 28 and a system according to the one shown in Fig. 1 shown design variant.

[0058] The internal combustion engine 28 has at least one intake manifold 29 for supplying the internal combustion engine 28 with air and at least one cylinder 30 for combustion.

[0059] During the Fig. In the embodiment shown in 9, the discharge point 4 of system 1 is arranged on the suction pipe 29 and is designed to discharge the operating fluid into the suction pipe 29. In the embodiment shown in the Fig. In the embodiment shown in Figure 10, the dispensing point 4 is arranged on the cylinder 30 and is designed for dispensing the operating fluid into the cylinder 30. Reference symbol list 1 system 2 motor vehicles 3 Tank 4 Delivery point 6 shut-off valve 7 Ball check valve 8 Line 9. Pump 10 Valve arrangement 11 integral component 12 first connection 13 second connection 14 third connection 15 Intake pipe 16 Return line 17 first filter module 21 Control unit 22 electrical connection 26 second filter module 27 beak valve 28 Internal combustion engine 29 Intake manifold 30 cylinders

Claims

[1] System (1) for providing an operating fluid in a motor vehicle (2) comprising a tank (3) in which the operating fluid can be stored and a dispensing point (4) at which the operating fluid can be provided, further comprising a bidirectionally operable pump (9) for pumping the operating fluid, functionally arranged between the tank (3) and the dispensing point (4), and further comprising a suction line (15) and a return line (16) which are functionally arranged parallel to each other between the pump (9) and the tank (3), wherein the operating fluid can be pumped back to the tank (3) via the return line (16) past the suction line (15), wherein a shut-off valve (6) is arranged in the return line (16), characterized by, that the shut-off valve (6) is designed as a nozzle valve (27) and prevents the suction of operating fluid from the tank (3) via the return line (16). [2] System (1) according to claim 1, wherein the nozzle valve (27) is designed such that a pressure loss generated by the nozzle valve (27) during a return pump operation of the feed pump (9) is smaller than a pressure loss generated by all other components in the return line (16). [3] System (1) according to claim 1 or 2, wherein a further shut-off valve (6) is arranged in the return line (16) in the return direction upstream or downstream of the nozzle valve (27). [4] System (1) according to one of the preceding claims, wherein a shut-off valve (6) is also arranged in the suction line (15), which prevents the operating fluid from being pumped back through the suction line (15) to the tank (3). [5] System (1) according to one of claims 3 or 4, wherein several of the shut-off valves (6) are combined in an integral component (11). [6] System (1) according to one of the preceding claims, wherein a first filter module (17) is arranged on or in the intake line (15). [7] System (1) according to one of the preceding claims, wherein a second filter module (26) is arranged at or in the discharge point (4) or at or in a line (8) between the delivery pump (9) and the discharge point (4). [8] System (1) according to any of the preceding claims, wherein the operating fluid is water. [9] System (1) according to one of the preceding claims, wherein the system (1) comprises a control unit (21) with which the delivery pump (9) can be controlled. [10] Motor vehicle (2) with an internal combustion engine (28) and a system (1) according to one of the preceding claims, wherein the internal combustion engine (28) has at least one intake manifold (29) for supplying the internal combustion engine (28) with air and at least one cylinder (30) for combustion, wherein the discharge point (4) of the system (1) is arranged on or in the intake manifold (29) and is configured for discharging the operating fluid into the intake manifold (29) or the discharge point (4) is arranged on the cylinder (30) and is configured for discharging the operating fluid into the cylinder (30).

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