VALVE FOR A MOTOR VEHICLE

Description

[0001] The invention relates to a valve for a motor vehicle, in particular for a coolant circuit in a motor vehicle, comprising a housing which has a cavity into which an inlet and an outlet open, wherein the inlet is connected to the outlet in an open state of the valve by a flow path running through the cavity, a valve opening arranged between the inlet and the outlet along the flow path in the cavity and a closure which is movable relative to the housing from a first position along an adjustment path to a second position, wherein the closure closes the valve opening to a lesser degree in the first position than in the second position.

[0002] Various valves for motor vehicles are known from the prior art. For example, a corresponding valve, also suitable for use in a motor vehicle's coolant circuit, is disclosed in document EP 3 453 930 A1. In such a valve, an armature is moved by means of an electromagnet under the influence of a spring force. In order to determine the actual position of the armature, this document proposes to incorporate a permanent magnet on the valve and a magnetic field sensor in the cavity, which detects the position of at least one valve.

[0003] However, it has been shown that such a setup can only be produced with great effort and that only a low level of measurement accuracy is achieved, so that the position of the closure or the position of the valve can only be determined with low accuracy.

[0004] This is where the invention comes in. The object of the invention is to provide a valve of the type mentioned above in which the state of the valve can be determined in a simple and at the same time accurate way during operation.

[0005] This problem is solved according to the invention by a valve of the type mentioned at the outset, in which a permanent magnet is connected to the closure, such that a movement of the closure along the adjustment path causes a movement of the permanent magnet, wherein a sensor is arranged outside the cavity with which a position of the permanent magnet can be detected.

[0006] Within the scope of the invention, it was recognized that both the high manufacturing costs and the low accuracy of the position detected by the sensor can be avoided if the sensor is not arranged inside the cavity as proposed in the prior art, but rather positioned outside the cavity. This easily prevents a fluid flowing through the valve, particularly a coolant, from surrounding the sensor and thus distorting the measurement result. Furthermore, positioning the sensor outside the cavity eliminates the need to route the sensor's data lines out of the cavity, which is filled with fluid when the valve is open. This avoids openings in the housing for the data lines, which would otherwise require complex sealing against the fluid.Furthermore, this allows for precise positioning of the closure across its entire adjustment range. Such a valve can be designed in a variety of ways. For example, it can be a slide valve, in which the closure moves along a sealing surface, or a poppet valve, in which the closure moves perpendicular to the sealing surface.

[0007] The permanent magnet is usually connected to the clasp in such a way that a movement of the clasp, particularly along its adjustment path, causes a movement of the permanent magnet. For this purpose, the permanent magnet can be connected to the clasp via a mechanism such as a gear system.

[0008] A particularly simple embodiment according to the invention is achieved when the permanent magnet is rigidly connected to the clasp via a bracket. A movement of the permanent magnet then corresponds to a movement of the clasp, so that by detecting the movement of the permanent magnet, the corresponding movement of the clasp can be directly inferred.

[0009] To ensure reliable actuation of the valve, an electromagnet is preferably provided, with which the closure can be moved along the adjustment path. The closure is designed as a plate-shaped component with openings, which is movable along a longitudinal direction or along an axis of a track of the electromagnet and is kinematically, in particular rigidly, connected to an armature of the electromagnet.

[0010] The clasp can be connected to the armature in virtually any way, in particular by force-fit or form-fit. A connection with play can also be provided, so that when the armature moves along an axis of the electromagnet, its movement is not transmitted immediately upon a change of direction, but only after the armature has moved a distance predefined by the play, in order to achieve favorable force distribution. For this purpose, for example, a projection of the armature or a component rigidly connected to the armature, such as a sleeve, can be provided. This sleeve engages in a corresponding recess in the clasp, such as a window, with play, thus transmitting the armature's movement via the projection or component and end stops in the recess to the clasp. As a result, when moving from an extreme position, initially only the armature is affected, and only after the play has been overcome, or...When the cantilever or component rests against a stop, the closure also moves, thus reducing the masses that need to be accelerated at the start of the movement.

[0011] Furthermore, a spring can be provided against which an opening or closing movement of the closure is carried out by means of the electromagnet, so that a defined position of the closure is ensured in a de-energized state of the valve.

[0012] At least one valve opening typically corresponds to a shape or contour of the closure, which may also have openings corresponding to the valve opening(s), such that the valve is closed when the valve opening(s) is / are covered by the closure. Similarly, the valve is open when the closure does not cover the valve opening, or when one or more openings of the closure are moved into a position corresponding to the valve opening(s) by a corresponding movement of the closure. It can therefore be provided that one or more openings of the closure are arranged directly adjacent to the valve opening(s) in the first position of the closure, so that a fluid flowing through the inlet into the cavity can flow through the opening of the closure and the valve opening leading to the outlet.In the second position of the closure, a valve opening can be completely covered by the closure, so that no flow through the corresponding valve opening is possible.

[0013] The valve can also be configured with one inlet and multiple outlets, whereby, depending on the position of the closure, a first valve opening of a first outlet or a second valve opening of a second outlet is opened or closed. By moving the closure along its adjustment path, a flow path from the inlet to a first outlet or to a second outlet can thus be created or blocked.

[0014] For example, the valve may be designed to have an inlet, a first outlet, and a second outlet, whereby a fluidic connection between the inlet and the first outlet and / or the inlet and the second outlet can be established and interrupted by moving the closure along its adjustment path. This provides a structurally simple valve that allows a medium flowing through the inlet to be selectively directed to one of the two outlets. A valve position can also be provided in which both outlets are closed, preventing any flow through the valve.

[0015] To achieve a particularly simple design, the valve can be configured so that in its first position, it closes one or more valve openings leading from the cavity to the second outlet and opens one or more valve openings leading from the cavity to the first outlet. Similarly, the valve can be configured so that in its second position, it opens one or more valve openings leading from the cavity to the second outlet and closes one or more valve openings leading from the cavity to the first outlet. Thus, by moving the valve from its first to its second position, flow from the inlet through the cavity to the first outlet can be stopped, and flow from the inlet through the cavity to the second outlet can be allowed.With such a valve, for example, the flow of a medium in a coolant circuit can be selectively directed either into a heat exchanger or into a bypass line bridging the heat exchanger. To achieve favorable flow conditions within the valve, preferably at least two valve openings per outlet are provided, to which the inlet can be connected via the valve.

[0016] It is advantageous if the permanent magnet is located within the housing so that, when a fluid flows from the inlet through the cavity to the outlet with the valve open, the permanent magnet is surrounded by the fluid. This eliminates the need for a passage in the housing through which the movement of the closure is transmitted from the interior of the housing or from the cavity to the exterior. Consequently, the need for a complex seal for such a passage is completely eliminated.

[0017] Preferably, the sensor is positioned on the outside of the housing so that, when a fluid flows from the inlet through the cavity to the outlet with the valve open, the sensor is not surrounded by the fluid. This results in a particularly accurate measurement and a long service life for the sensor.

[0018] To achieve highly accurate measurements, it is advantageous for the housing to be made of a non-magnetizable material, particularly a plastic or a metal, preferably aluminum. This allows the position of the permanent magnet, which may be located inside the housing, to be determined with high accuracy using a sensor located outside the housing. For particularly precise measurements, it is preferred that the permanent magnet be positioned in the cavity such that, when the valve is open, it is located outside a direct connection between the inlet and outlet. This results in low flow velocities at the magnet, leading to exceptionally low abrasive wear and a particularly long service life. According to the invention, the permanent magnet is positioned at its end in a lateral recess within the cavity.In particular, the permanent magnet is positioned off-center, especially since flow velocities are typically very low in this area. The connection between the closure, which is usually located centrally in the cavity, and the permanent magnet, which is usually located at one end of the cavity, is made via a rigid bracket.

[0019] To obtain a particularly accurate measurement result, the permanent magnet is positioned within the cavity such that, in every possible position of the valve's closure, the distance to the housing is less than 10 mm, and in particular less than 5 mm. This minimal distance ensures a good measurement result. While a small distance is advantageous for an accurate measurement, a minimal distance between the housing and the permanent magnet also prevents the magnet from sliding against the housing when the closure moves, which would reduce its service life. Therefore, the permanent magnet is typically positioned away from the housing in every operating position of the closure.

[0020] To achieve a compact design and highly accurate measurements, it is further advantageous if the sensor is positioned on the outside of the housing at a location corresponding to the position of the permanent magnet. Despite being positioned outside the housing, the sensor is then located at a minimal distance from the permanent magnet, allowing for particularly precise detection of any movement of the permanent magnet, especially parallel to the adjustment path. Preferably, the sensor is positioned at a distance of less than 5 mm from the housing. The sensor can also be bonded to the housing, for example, using a potting compound such as a resin.

[0021] Advantageously, the distance between the permanent magnet and the sensor is less than 15 mm in every possible position of the closure during operation of the valve, and less than 10 mm according to the invention. This allows the position of the permanent magnet and the sensor to be determined with particular accuracy, even through a housing wall and over the entire adjustment range.

[0022] It has proven advantageous for the sensor to incorporate a Hall sensor or be formed by a Hall sensor. This allows the position of the permanent magnet to be determined with exceptional accuracy, even through the housing.

[0023] The output voltage of a sensor used to detect the position of a permanent magnet, particularly a Hall sensor, often cannot be directly processed by vehicle electronics. Therefore, it can be advantageous to have electronics connected downstream of the Hall sensor, or for the Hall sensor to be part of an integrated circuit that can generate a further processable output voltage based on the sensor's output signal. For this purpose, the sensor can be housed in a sensor module, which can also contain the necessary electronics.

[0024] To facilitate easy integration of the valve into a vehicle with existing on-board electronics, it is preferably provided that an electrical output signal from a sensor module containing the sensor corresponds to a predefined first voltage when the valve is closed. This voltage can, for example, be between 0.5 volts and 1.0 volts, typically 0.75 volts.

[0025] It is then preferably provided that an electrical output signal from a sensor module containing the sensor corresponds to a predefined second voltage when the valve is open. This second voltage usually differs from the first voltage and can, for example, be between 4.0 volts and 4.5 volts, typically in the range of approximately 4.25 volts.

[0026] The sensor module can, for example, contain the sensor and an electronic component with which an electrical output voltage of the sensor can be amplified and shifted relative to a zero point in order to achieve targeted output voltages of the sensor module at certain valve states.

[0027] Such defined voltages can be achieved, for example, during calibration, which can be performed during manufacturing, quality control, or functional testing. A voltage measured during operation, lying between the predefined first and second voltages, can then be used to determine the position of the shutter at any given position via an output voltage from the sensor module. This relationship can be linear, for example, and is based on the current actual position of the shutter.

[0028] Further features, advantages, and effects of the invention will become apparent from the exemplary embodiment described below. The drawings referenced therein show: Fig. 1 and 2 a valve designed according to the invention in different operating states; Fig. 3 another view of a valve according to the invention; Fig. 4 a detail of a valve according to the invention.

[0029] Fig. 1 bis 3 show a sectional view of a valve 1 designed as a slide valve according to the invention, wherein Fig. 1 the valve 1 is shown in a first operating state in which an inlet 4 of the valve 1 is fluidically connected to a first outlet 5 of the valve 1, while Fig. 2 The valve 1 is shown in a second operating state in which the inlet 4 is fluidically connected to a second outlet 6, but there is no fluidic connection between the inlet 4 and the first outlet 5.

[0030] It is understood that a valve 1 according to the invention can also be designed with only one outlet 5, 6, more than one inlet 4 and / or more than two outlets 5, 6.

[0031] The in Fig. 1 As can be seen, the illustrated valve 1 has an inlet 4 and two outlets 5, 6, which open into a cavity 3. A sealing seat 13 with valve openings 7 is arranged between the cavity 3 and the first outlet 5, as well as between the cavity 3 and the second outlet 6, wherein valve openings 7 are provided both opening into the first outlet 5 and opening into the second outlet 6.

[0032] Furthermore, a plate-shaped closure 8, which can be translationally displaced along an axis via an adjustment path by means of an electromagnet, is positioned in the cavity 3. This closure 8 has openings 17 and is rigidly connected to an armature 12 of the electromagnet. In the illustrated embodiment, a movement of the armature 12, which can be triggered by energizing a coil of the electromagnet, is transmitted to the closure 8 via a positive locking mechanism. For this purpose, the armature 12 and the closure 8 are positioned in a plane normal to a direction of movement or normal to a direction of an axis 21 of the armature 12 in the housing 2 such that the armature 12 and the closure 8 are only freely movable along the direction of movement or along the axis 21 relative to the housing. A sleeve 19 connected to the armature 12 engages in a window 20 of the closure 8 to transmit a force in the axial direction or along the axis 21.The force is transmitted parallel to the adjustment path from the armature 12 to the shutter 8. The window 20 is larger than the engaging part of the sleeve 19, as shown, so that the positive-locking force transmission occurs with some play, as the sleeve 19 rests against one of two stops 22 of the window 20, depending on the direction of movement. As can be seen, a spring 16 is positioned between the armature 12 and a core 11 of the electromagnet to achieve a favorable force profile during a switching operation.

[0033] As shown in the Fig. 1 In the first operating state of the valve 1 shown, in which the closure 8 is in a first position, two openings 17 of the closure 8 are positioned immediately adjacent to valve openings 7, which open into the first outlet 5, so that in the Fig. 1 In the first operating state shown, a fluidic connection exists from the inlet 4 via the openings 17 of the closure 8 and the valve openings 7, which open into the first outlet 5. As an example, a flow path 18 is shown, running from the inlet 4 through the cavity 3, one of the openings 17 of the closure 8, and one of the valve openings 7 opening into the first outlet 5, along which a medium can flow from the inlet 4 to the first outlet 5.

[0034] The valve openings 7 of the sealing seat 13, which open into the second outlet 6, are closed by the closure 8 in the first operating state, so that there is no fluidic connection between the inlet 4 and the second outlet 6. The closure 8 is therefore located in the Fig. 1 The first operating state shown is in a first extreme position in which the valve openings 7 leading into the first outlet 5 are completely open and the valve openings 7 leading into the second outlet 6 are closed.

[0035] Conversely, in the Fig. 2 In the second operating state shown, in which the closure 8 is in the second position, those valve openings 7 of the sealing seat 13 which open into the first outlet 5 are closed by the closure 8, and the valve openings 7 of the sealing seat 13 which open into the second outlet 6 are opened by the closure 8 or an opening 17 of the closure 8, so that a fluidic connection between the inlet 4 and the second outlet 6 is given via the valve openings 7 opening into the second outlet 6. As an example, an open flow path 18 is shown, running from the inlet 4 through the cavity 3, one of the openings 17 of the closure 8, and a valve opening 7 opening into the second outlet 6, along which a medium can flow from the inlet 4 to the second outlet 6. The closure 8 is thus located in the state shown. Fig. 2 The second operating state shown is in a second extreme position, in which the valve openings 7 leading into the first outlet 5 are completely closed and the valve openings 7 leading into the second outlet 6 are completely open.

[0036] To enable continuous and simple monitoring of the position of the closure 8, even during operation, a permanent magnet 9, kinematically (here rigidly) connected to the closure 8, is provided in the cavity 3. As can be seen, the permanent magnet 9 is arranged at an upper end of the cavity 3 in a lateral recess 15, so that it neither obstructs the flow through the cavity 3 nor is the magnetic field of the permanent magnet 9, usually a cooling fluid such as water, possibly with appropriate additives, affected by the flow. Furthermore, only a low flow velocity is typically reached at the corresponding position, resulting in favorable wear. The permanent magnet 9 is connected to the closure 8 via a bracket 14, which is located in the Fig. 1 and Fig. 2 is only partially visible, especially since it lies partly outside the cutting plane running through a longitudinal axis of the electromagnet, as can be seen from Fig. 3 results.

[0037] To detect the position of the permanent magnet 9, a sensor module 10 is arranged on the outside of the housing 2. This sensor module 10 is designed as an integrated circuit with a Hall sensor. It can detect the position of the magnetic field generated by the permanent magnet 9 through the housing 2, which in the illustrated embodiment is made of aluminum, but can of course also be made of other materials such as plastic. The sensor module 10 can be bonded to the housing 2 using a potting compound such as resin to achieve a stable and robust connection. Alternatively or additionally, the sensor module 10 can also be positively and / or force-fitted to the housing 2, in particular by means of a screw connection.

[0038] The sensor module 10 can, for example, be calibrated such that it is in Fig. 1 The first operating state shown, i.e., when a fluidic connection exists from inlet 4 to the first outlet 5 and a fluidic connection from inlet 4 to the second outlet 6 is closed, outputs an electrical voltage of approximately 0.75 volts and is in the Fig. 2 The second operating state shown, i.e., when a fluidic connection from inlet 4 to the first outlet 5 is closed and a fluidic connection from inlet 4 to the second outlet 6 exists, outputs an electrical voltage of approximately 4.25 volts, so that it is electronically easy to determine the operating state of the valve 1 or also the position of the closure 8 between the two. Fig. 1 and Fig. 2 The extreme positions shown along the adjustment path can be detected. For example, the current actual position of the shutter 8 between the first operating state and the second operating state can be determined via a linear relationship between the output voltage of the sensor module and the actual position.

[0039] Calibration of these voltages is achieved by means of electronics connected downstream of the Hall sensor in sensor module 10. This electronics amplifies the Hall sensor's output voltage and shifts it relative to a reference potential or zero point. This allows defined voltages to be output regardless of manufacturing tolerances or the actual distance between the permanent magnet 9 and the Hall sensor when valve 1 is open and closed. These defined voltages can then be processed further in vehicle electronics. Calibration of sensor module 10 can be performed, for example, as part of a functional test after valve 1 has been manufactured.

[0040] Fig. 3 shows a top view of the already in Fig. 1 and Fig. 2 Valve 1 shown. As can also be seen here, the permanent magnet 9 is connected to the closure 8 via a bracket 14 and is positioned off-center in the cavity 3, so that the flow velocity in the area of ​​the permanent magnet 9 is low.

[0041] Fig. 4 Figure 1 shows an armature 12 of a valve 1 according to the invention, including a closure 8 connected to it. The connection between the armature 12 and the closure 8 in the direction of an axis 21 of the electromagnet, or in the direction of movement for transmitting a movement, is positively engaged via a sleeve 19 that engages in a window 20 of the closure 8. This sleeve 19 is rigidly connected to the armature 12 or is part of the armature 12. As shown, the sleeve 19 can also be positioned with some play in the window 20, so that when the armature 12 moves from an extreme position in a direction along the axis 21, initially only the armature 12 together with the sleeve 19 moves, until the sleeve 19 is moved across a width of the window 20 in the axial direction and thus rests against a stop 22 of the window 20 at its end. With further movement of the armature 12 in the corresponding direction, the closure 8 is then closed by the sleeve 19 engaging in the window 20.The sleeve 19, which rests against a stop 22 of the window 20, is moved along with the movement of the valve 8. A movement in the opposite direction can also occur, whereby the force required to move the valve 8 is transferred from the anchor 12, via the sleeve 19, to the stop 22 located at the opposite end of the window 20 after the sleeve 19 has moved within the window 20. This enables particularly efficient actuation of the valve 1.

[0042] As can be seen here, the closure 8 is essentially plate-shaped, and the openings 17 in the closure 8, which correspond to the valve openings 7 depending on the position of the closure 8, are approximately rectangular. Furthermore, it is also shown in Fig. 4 It is evident that the permanent magnet 9 is connected to the armature 12 via a bracket 14, so that the permanent magnet 9, as already shown in Fig. 1 and Fig. 2 shown in operation is arranged close to a housing wall in order to achieve an accurate measurement result despite the sensor module 10 being arranged on the outside of the housing 2.

[0043] Although in the Fig. 1 bis Fig. 4 Where a valve 1 designed as a slide valve is shown, in which the closure 8 is thus moved essentially along a sealing surface of the sealing seat 13 and normal to a flow, it is understood that the invention is not limited to a slide valve, but a valve 1 according to the invention can of course also be designed with a closure 8 or sealing element that is not moved along a sealing surface and / or approximately along the flow, for example as a seat valve.

[0044] With a valve 1 according to the invention, the current position of the closure 8 or a valve position can be determined in a simple, robust, and precise manner over the entire adjustment range, even during operation. Such a valve 1 can, in principle, be used in a wide variety of applications. A corresponding valve 1 is preferably used in a motor vehicle, particularly in a motor vehicle's coolant circuit.

Claims

1. Slide valve (1) for a coolant circuit in a motor vehicle having a housing (2), which has a cavity (3), into which an inlet (4) and an outlet (5, 6) open, wherein the inlet (4) is connected to the outlet (5, 6) in an open state of the slide valve (1) by a flow path (18) running through the cavity (3), a valve opening (7) arranged between the inlet (4) and the outlet (5, 6) along the flow path (18) in the cavity (3) and a plate-shaped closure (8), which can be moved relative to the housing (2) from a first position along an adjustment path into a second position, wherein the closure (8) closes the valve opening (7) in the first position to a lesser extent than in the second position, characterized in that a permanent magnet (9) is rigidly connected to the closure (8) via a bracket such that a movement of the closure (8) along the adjustment path causes a movement of the permanent magnet (9), wherein the permanent magnet is arranged in the cavity in such a way that the permanent magnet (9) has a distance to the housing (2) of less than 10 mm in every position of the closure (8) possible when the slide valve (1) is in operation and wherein a sensor is arranged outside the cavity (3), with which a position of the permanent magnet (9) can be detected, wherein the permanent magnet (9) is positioned at the end in a lateral recess (15) in the cavity (3) in such a way that this is arranged outside a direct connection between the inlet (4) and outlet (5, 6) when the slide valve (1) is open and wherein the distance between the permanent magnet (9) and the sensor is less than 10 mm in every position of the closure (8) possible when the slide valve (1) is in operation.

2. Slide valve (1) according to Claim 1, characterized in that an electromagnet is provided, with which the closure (8) can be moved along the adjustment path.

3. Slide valve (1) according to Claim 1 or 2, characterized in that the slide valve (1) has an inlet (4), a first outlet (5) and a second outlet (6), wherein a movement of the closure (8) along the adjustment path can establish and break a fluidic connection between the inlet (4) and the first outlet (5) and / or a fluidic connection between the inlet (4) and the second outlet (6) .

4. Slide valve (1) according to Claim 3, characterized in that the closure (8), in the first position, closes one or more valve openings (7) opening from the cavity (3) into the second outlet (6) and opens one or more valve openings (7) opening from the cavity (3) into the first outlet (5).

5. Slide valve (1) according to Claim 1 or 4, characterized in that the permanent magnet (9) is arranged in the housing (2) such that when a fluid flows from the inlet (4) through the cavity (3) to the outlet (5, 6) when the slide valve (1) is open, fluid flows around the permanent magnet (9).

6. Slide valve (1) according to one of Claims 1 to 5, characterized in that the sensor is arranged on the outside of the housing (2) such that when a fluid flows from the inlet (4) through the cavity (3) to the outlet (5, 6) when the slide valve (1) is open, fluid does not flow around the sensor.

7. Slide valve (1) according to one of Claims 1 to 6, characterized in that the housing (2) consists of a non-magnetizable material, in particular a plastic or a metal, preferably aluminium.

8. Slide valve (1) according to one of Claims 1 to 7, characterized in that the permanent magnet (9) is arranged in the cavity (3) in such a way that the permanent magnet (9) has a distance to the housing (2) of less than 5 mm in every position of the closure (8) possible when the slide valve (1) is in operation.

9. Slide valve (1) according to one of Claims 1 to 8, characterized in that the sensor is arranged on the outside of the housing (2) at a position corresponding to a position of the permanent magnet (9).

10. Slide valve (1) according to one of Claims 1 to 9, characterized in that a distance between the permanent magnet (9) and the sensor is less than 5 mm in every position of the closure (8) possible when the slide valve (1) is in operation.

11. Slide valve (1) according to one of Claims 1 to 10, characterized in that the sensor has a Hall sensor or is formed by a Hall sensor.

12. Slide valve (1) according to one of Claims 1 to 11, characterized in that an electrical output signal of a sensor module (10), which contains the sensor, corresponds to a predefined first voltage when the slide valve (1) is closed.

13. Slide valve (1) according to one of Claims 1 to 12, characterized in that an electrical output signal of a sensor module (10), which contains the sensor, corresponds to a predefined second voltage when the slide valve (1) is open.