Opening device for a motor vehicle door

Abstract

The invention relates to an opening device for a motor vehicle door, which is equipped with a tappet (6), also with an electromotive drive (5) for the tappet (6), and with at least one sensor (7) for detecting an actuating movement of the tappet (6). The tappet (6) can be moved at least between a retracted and an extended position with respect to a housing (3, 4) accommodating the drive (5) and the tappet (6). According to the invention, the sensor (7) is designed as a stationary pressure sensor (7) in the sealed housing (3, 4). The stationary pressure sensor (7) detects pressure fluctuations caused by an actuating movement of the tappet (6) with respect to the housing (3, 4) in its interior.

Description

[0001] Description

[0002] Opening device for a motor vehicle door

[0003] The invention relates to an opening device for a motor vehicle door, comprising a plunger, further comprising an electric motor drive for the plunger, and comprising at least one sensor for detecting an actuating movement of the plunger, wherein the plunger can be moved at least between an extended and a retracted position relative to a housing accommodating the drive and the plunger.

[0004] Modern vehicles are often designed and engineered, particularly for aerodynamic reasons, in such a way that an exterior door handle is either omitted entirely or reduced to its function as a switch or sensor to trigger an electric motor opening mechanism inside the vehicle's door lock. In principle, such a sensor or switch can also be omitted if wireless communication between a transmitter and the vehicle is used to open the lock. In any case, the electric motor opening process of the lock results in the corresponding vehicle door being "open," but unable to be swung open by a user wishing to enter.This also requires increasing or generally adjusting the gap between a door leaf of the vehicle door in question and the bodywork that accommodates the vehicle door to such an extent that the user in question can reach behind the door leaf and swing it open.

[0005] In principle, it is of course also possible to equip the vehicle door in question with an electric motor for opening, either in addition to or as an alternative to the opening mechanism. Generally, however, the complete opening of the door leaf from the described gap position is initiated by the user wishing to enter. This presupposes that the required gap position is actually reached. The sensor serves this purpose, detecting the movement of the plunger acting on the door leaf, specifically at least its retracted and extended positions. After the door leaf has fully swung open, or after the opening process is complete, the plunger is generally moved from its previously extended position to its retracted position to prevent any potential damage to the plunger when the vehicle door is open.

[0006] A mounting device, such as that promoted by the applicant, is the subject of WO 2020 / 187360 A1. This device additionally incorporates a locking mechanism that can hold a door element or door leaf in place. Furthermore, the locking mechanism can be electrically operated.

[0007] A comparable installation device is the subject of DE 10 2007 021 840 B4 or DE 10 2020 131 792 B3. In the latter case, a pyrotechnic device is additionally provided, which is used in emergency operation.

[0008] The generic and therefore closest prior art according to EP 3 430 217 B1 concerns a method for operating a vehicle door. This method detects a movement associated with the unlocked vehicle door. For this purpose, in conjunction with a door presentation system for such a vehicle door, not only is a presentation actuator implemented, but also a motion sensor for detecting movement associated with the door. The motion sensor in question could, for example, be an accelerometer. Such accelerometers, or semiconductor-based sensors in general, are sometimes sensitive to harmful environmental influences. These can include dust, humidity, temperature, etc.This applies particularly when the positioning movement of the plunger is to be detected, because for this purpose the plunger must be extended, at least partially, relative to the vehicle door or an associated door leaf. As a consequence, functional impairments are to be expected. The invention aims to remedy this problem entirely.

[0009] The invention is based on the technical problem of further developing such a support device for a motor vehicle door in such a way that reliable operation is guaranteed under all conceivable environmental conditions, even over long time scales.

[0010] To solve this technical problem, the invention proposes, in a generic opening device for a motor vehicle door, that the sensor is designed as a stationary pressure sensor in the sealed housing, which detects pressure fluctuations inside caused by an positioning movement of the plunger relative to the housing.

[0011] In contrast to the prior art, particularly according to the generic patent EP 3 430 217 B1, the invention therefore employs a sensor that detects the positioning movement of the plunger not directly, but rather indirectly. This is because the sensor is a stationary pressure sensor located in the housing that contains the drive and the plunger. The housing in question is designed to be sealed, meaning it has only one sealed opening through which the plunger is extended and retracted. As a result, positioning movements of the plunger relative to the housing cause pressure fluctuations inside the sealed housing. For example, an extension movement of the plunger causes the pressure in the sealed housing to drop, or a negative pressure is observed compared to its retracted position.Conversely, when the plunger moves from its extended to its retracted position, the pressure inside the housing increases; that is, an overpressure is observed inside the housing compared to the extended position. These pressure fluctuations inside the housing, caused by each movement of the plunger relative to the housing, are now detected by the stationary pressure sensor.

[0012] As a result, the absolute values ​​from the stationary pressure sensor in the sealed housing allow conclusions to be drawn about the plunger's position (retracted or extended). Furthermore, the pressure's behavior over time provides additional information about the plunger's operating speed. For example, a steep pressure increase corresponds to a high operating speed, while a slow pressure increase over time corresponds to a low operating speed. Therefore, in conjunction with the plunger's initial position (retracted or extended), the pressure sensor can provide comprehensive information about the plunger's operating movement.

[0013] If the pressure sensor is or will be connected to a control unit, the previously specified pressure increase gradients over time, as well as absolute values, can be evaluated and compared as actual values ​​with, for example, target values ​​stored in the control unit. This allows conclusions to be drawn about the actuator speed as well as its position (retracted or extended). Finally, the aforementioned target-actual value comparison also allows a determination of whether the observed values ​​correspond to the proper functioning of the actuator and thus the entire positioning device, or whether functional problems exist or are to be expected in the future. In other words, with the help of the pressure sensor, the control unit, and the recorded actual pressure values ​​compared to the target values, additional predictions and diagnostic statements can be made.This is where the main advantages lie.

[0014] Further advantageous embodiments are explained below. The plunger is generally equipped with a front seal for contact with a vehicle body or a door leaf. The invention is based on the understanding that the actuating device, with its sealed housing containing the drive and the plunger, is generally located inside the door leaf. This allows the extended plunger to move against the vehicle body, ensuring that the door leaf is opened into the previously described gap position. However, the housing in question, and thus the actuating device, can also be placed inside the vehicle body and, in its extended state, actuate the door leaf from this position.

[0015] In any case, the plunger is usually equipped with at least one cavity that communicates with the interior of the sealed housing. That is, the plunger is advantageously a typically cuboid-shaped component made of plastic. This component is equipped with the cavity in question within its interior. The cavity, and consequently the cuboid-shaped component, can communicate with the interior of the sealed housing. For this purpose, the cavity in question, and thus also the cuboid-shaped housing, is sealed by at least one membrane both to the outside and inside of the housing.

[0016] The membrane in question is generally a so-called breathable membrane, which allows air to pass through but not water. This creates a pressure equalization inside the sealed housing via the plunger, linked to the plunger's adjustment movements. Nevertheless, the previously described pressure fluctuations are still observed and recorded by the stationary pressure sensor and the control unit that evaluates its signals. Such breathable membranes are known, for example, under the brand name "Gore-Tex." Generally, these are membranes made of PTFE (polytetrafluoroethylene) that are microporous.

[0017] The housing containing the actuator and plunger is itself divided into a drive housing, which also houses the actuator and plunger, and an electronics housing, which contains the previously mentioned control unit and pressure sensor. Both housing components are typically made of plastic, connected by a diaphragm, and can communicate with each other via this diaphragm, thus ensuring pressure equalization. Otherwise, the drive housing is sealed off from the electronics housing.

[0018] This means that pressure fluctuations in the drive housing caused by the plunger's movements are transmitted to the electronics housing via the diaphragm that couples the drive housing and the electronics housing. In this way, the stationary pressure sensor located in the electronics housing can detect these fluctuations and evaluate them using the control unit. This design protects the control unit, including the pressure sensor, from environmental influences, as no moisture or dirt can penetrate the sealed electronics housing, even if a seal surrounding the plunger in the drive housing should become worn. In principle, this even makes a separate seal somewhat unnecessary.

[0019] In addition to the previously described and essential stationary pressure sensor in the sealed housing, at least one position sensor can be provided on the plunger. While not strictly necessary for the reasons already explained, this represents a safety measure to detect the plunger's retracted and extended positions not only via the pressure sensor but also via the one or two position sensors provided on the plunger. The position sensor in question is generally a magnet, and in particular a permanent magnet, whose presence can be detected by a position sensor designed as a Hall effect sensor. Usually, two position sensors are present, corresponding to the retracted and extended positions of the plunger.In principle, the position transmitter can also be designed as, for example, a reflective surface, and the position sensor can work optically as a light sensor including receiver.

[0020] The invention also relates to a method for operating such a positioning device. In this method, the stationary pressure sensor in the sealed housing detects the positioning movements of the plunger in the form of pressure fluctuations inside the housing relative to the housing. For this purpose, and in detail, the pressure sensor can detect both pressure changes inside the sealed housing associated with a positioning movement of the plunger with its seal in contact with the vehicle body or the door leaf, and pressure changes that occur when the seal, and thus the plunger, detaches from the vehicle body or door leaf. This will be explained in more detail with reference to the description of the figures.

[0021] Finally, the electric motor drive located inside the sealed housing, and specifically inside the sealed drive housing, is generally equipped with an overload spring. This overload spring usually allows or even facilitates the return movement of the extended plunger towards its retracted position. Depending on the pressure change detected by the pressure sensor, the drive can be designed so that, during its return movement, the drive retracts the plunger at a suitably adjusted speed. This allows for handling various practical situations. Even when the plunger is in its extended position, a user can still close the corresponding vehicle door. The overload spring allows this because it enables the return movement of the extended plunger towards its retracted position.Provided that the seal, usually located at the head of the plunger, remains in contact with the vehicle body or door leaf during this process, a pressure change occurs inside the sealed housing. The control unit interprets this pressure change as the user attempting to close the door. Consequently, the control unit can activate the electric motor to retract the plunger.

[0022] The speed of the plunger's return movement, driven by the electric motor, can also be adjusted based on the rate of change of the measured pressure. If a large pressure gradient is observed, meaning a rapid pressure change per unit of time, this can be interpreted as an increased closing speed of the vehicle door initiated by the user. Consequently, the control unit can then drive the electric motor at a higher speed.

[0023] That is, different speeds for controlling the electric motor drive can be derived from the temporal gradients of the pressure changes by the control unit.

[0024] This also generally applies if, during or before the described user-operated closing process of the vehicle door, the seal on the plunger has become detached from the vehicle body or the door leaf. In this case, this process can also be detected by a pressure change at the pressure sensor and may lead to the electric motor retracting at an adjusted speed via the control unit, in this case at a reduced speed compared to the previous scenario. In any case, gradients of pressure change, i.e., increases or decreases in pressure over time, can be processed by the control unit in such a way that the speed of the electric motor is varied accordingly.

[0025] This also applies if the plunger is slowed down or blocked during the transition from its retracted to its extended position. This occurs, for example, when the vehicle door is frozen shut to the vehicle body. Any deformation can also lead to this. In any case, this results in the pressure inside the sealed housing remaining constant. The associated absence of a pressure gradient over time indicates a blockage of the plunger. The control unit can then utilize this information by applying increased electrical energy to the plunger to release the blockage.

[0026] In this case as well, the control unit evaluates the temporal pressure gradients of the pressure sensor signal. Depending on the nature of these pressure gradients—whether rising or falling, whether a specific pattern is observed, or simply no gradient at all—the control unit adjusts the application of pressure to the electric motor drive accordingly. The scenarios described in detail previously—along with other conceivable approaches—are possible and can be implemented. This is where the key advantages lie.

[0027] The invention is explained in more detail below with reference to a drawing that illustrates only one embodiment. The single figure, 1, shows the support device according to the invention in a schematic sectional view. Figure 1 depicts a support device for a motor vehicle door. A door leaf 1 of the motor vehicle door is visible. A motor vehicle body 2 is also shown schematically. In this embodiment, the support device, which will be described in more detail below, is arranged inside the door leaf 1. However, the support device can also be installed inside the motor vehicle body 2, for example, in a B-pillar of the motor vehicle body 2.

[0028] The basic structure of the setup device includes, firstly, a housing 3, 4 made of plastic. An electric motor drive 5 is arranged in the housing 3, 4. Also included is a plunger 6 that can be moved back and forth along a double arrow indicated in Fig. 1 by means of the electric motor drive 5.

[0029] In the embodiment shown in Fig. 1, only an output-side pinion of the electric motor drive 5 is visible. This pinion engages with a rack-like toothing of the plunger 6, thereby causing the plunger 6 to perform the positioning movements indicated by the double arrow. According to the embodiment, and without limitation, the housing 3, 4, the output gear of the electric motor drive 5, and the plunger 6 are made of plastic. In reality, the plunger 6 in this embodiment is a rod-shaped hollow cuboid made of plastic.

[0030] Furthermore, a sensor 7 is provided in the housing 3, 4. The sensor 7 detects the positioning movements of the plunger 6 along the double arrow shown in Fig. 1. In fact, the plunger 6 can move back and forth between the retracted position (shown as a solid line in Fig. 1) and the extended position (indicated by a dashed line). In the extended position (shown as a dashed line), the plunger 6 moves against the vehicle body 2 and ensures that the vehicle door, or its door leaf 1, which accommodates the lifting device, is raised relative to the vehicle body 2, taking into account a gap S. This allows a user to grasp the door leaf 1 and swing it fully open, as already described in the introduction.

[0031] According to the invention, the sensor 7 is designed as a stationary pressure sensor 7 within the sealed housing 3, 4. The pressure sensor 7 detects the positioning movement of the plunger 6 relative to the housing 3, 4 such that these positioning movements correspond to pressure fluctuations inside the housing 3, 4. The pressure sensor 7 detects these fluctuations and transmits them as signals to a control unit 8 electrically coupled to it. The control unit 8, in turn, can detect the pressure signals from the pressure sensor 7 with respect to absolute values ​​and gradients, i.e., pressure changes per unit of time. In the exemplary embodiment, the control unit 8 and the pressure sensor 7 are arranged on a common circuit board. This also applies to the position sensors 14, 15, which will be described subsequently.

[0032] Furthermore, the control unit 8 is capable of performing a target / actual value comparison of the absolute values ​​or gradients based on stored target values. This allows, for example, statements to be made about the functionality of the positioning device, any wear, aging effects, etc., as well as about the position of the plunger 6. In addition, the pressure fluctuations or pressure changes in the sealed housing 3, 4 allow conclusions to be drawn about the positioning movement of the plunger 6. Furthermore, it allows conclusions to be drawn about whether the plunger 6 is moved by a user, for example, together with the door leaf 1, into the closed position of the vehicle door relative to the vehicle body 2.

[0033] The sealed housing 3, 4 is divided into two parts according to the exemplary embodiment. In this context, a drive housing 3 is provided, which contains the electric motor drive 5 and the plunger 6. Furthermore, a second electronics housing 4 is provided, in which the control unit 8 is located together with the pressure sensor 7 and the two position sensors 14, 15. Both housing components 3, 4 are sealed against each other and connected only by a breathable membrane 9. The plunger 6 can be moved outside the housing 3, 4 by means of a surrounding seal.

[0034] Figure 1 shows that the plunger 6 is equipped with a front-facing seal 10. In fact, the seal 10 is located at the head of the plunger 6 and can, for example, be designed as an elastomer seal. The plunger 6 is equipped with an opening in the area of ​​the seal 10, which is closed by a further diaphragm 11. Furthermore, the plunger 6 is also provided with an additional third diaphragm 12, which, according to the exemplary embodiment, is inserted into an opening in the side wall of the cuboid plunger 6. In principle, it is also possible to use two opposing openings with diaphragms 12 located therein.

[0035] All the membranes 9, 11, 12 referred to above are designed to be air-permeable according to the exemplary embodiment, but prevent water from penetrating the interior of the plunger 6. Thus, the breathable membranes 9, 11, 12 additionally ensure that water or moisture cannot penetrate the interior of either the drive housing 3 or the electronics housing 4.

[0036] The basic assembly also includes a position sensor 13 on the plunger 6. In this exemplary embodiment, and without limitation, the position sensor 13 is a permanent magnet. In addition to the pressure sensor 7, the position sensor 13 can detect the extended and retracted positions of the plungers 6. For this purpose, the approach of the position sensor 13 to the associated position sensor 14, or the two position sensors 14 and 15, is detected, and corresponding signals are transmitted to the control unit 8. In fact, both the position sensor 14 and the position sensor 15 are located in the electronics housing 4. Furthermore, the design is such that the approach of the position transmitter 13 to the position sensor 14 corresponds to the retracted position of the plunger 6, while the approach of the position transmitter 13 to the position sensor 15 corresponds to the plunger 6 having assumed its extended position.Due to its hollow nature, the plunger 6 is equipped with a hollow passage 16. The hollow passage 16 is sealed to the outside of the housing 3, 4 and also to the inside of the housing 3, 4 by means of the diaphragms 11, 12.

[0037] The operating principle is as follows. As soon as the plunger 6 is moved from the retracted position (shown in solid lines in Fig. 1) to the extended position (shown in dashed lines), the seal 10 located at the head of the plunger 6 makes contact with the vehicle body 2, according to the exemplary embodiment. As a result, a pressure drop is initially observed at the pressure sensor 7 because the plunger 6 moves outside the sealed housing 3, 4 and any pressure equalization via the front diaphragm 11 and the two side diaphragms 12 does not occur immediately. Such pressure equalization is interrupted at the latest when the front seal 10 has come into contact with the vehicle body 2.The previously described pressure change (for example, the pressure drop) propagates via the diaphragm 9 from the drive housing 3 to the electronics housing 4 and can be detected there using the pressure sensor 7 and reported to the control unit 8.

[0038] As soon as the plunger 6, with its front seal 10, comes into contact with the vehicle body 2, the pressure remains essentially constant. The corresponding gradient, i.e., the pressure change per unit of time, is therefore zero or nearly zero, so that the control unit 8, based on the evaluation of the time-dependent signal from the pressure sensor 7, "knows" that the plunger 6 has reached the vehicle body 2 and is in contact with it via the seal 10.

[0039] As soon as, for example, an operator or user grasps the door leaf 1 through the gap S and fully swings it open, the contact between the front seal 10 of the plunger 6 and the vehicle body 2 is interrupted. This results in a pressure equalization between the outside and inside of the housing 3, 4. This pressure equalization manifests itself in a further pressure change, usually in the form of a pressure increase observed from the initial vacuum associated with the extension movement of the plunger 6. This increase is then interpreted by the control unit 8 as the release of the door leaf 1 from the vehicle body 2 together with the plunger 6. If the plunger 6 is in the extended position, this generally leads to the plunger 6 being moved – controlled by the control unit 8 – into its retracted position.For this purpose, the control unit 8 transmits a corresponding signal to the electric motor drive 5.

[0040] If the plunger 6 is in its extended position and the vehicle door or door leaf 1 describes the gap S with respect to the vehicle body 2, the user cannot swing the door leaf 1 open as described, but instead ensures that the door leaf 1 closes. Such a reverse movement of the plunger 6 is made possible by an additional overload spring, which is integrated into the drive train of the electric motor drive 5. In the event of a closing movement of the door leaf 1, the seal 10 located against the vehicle body 2 ensures that the plunger 6 is sealed against the housing 3, 4 and is then moved into its retracted position.This results in a pressure change and, regularly, a pressure increase, which propagates from the drive housing 3 via the diaphragm 9 to the electronics housing 4, where it is detected by the stationary pressure sensor 7 and transmitted to the control unit 8. Simultaneously, the control unit 8 interprets this process as an attempt by a user to close the door leaf 1.

[0041] Based on the pressure gradient associated with this closing movement, the control unit 8 can now actuate the electric motor 5 accordingly, varying its speed depending on the pressure gradient. If the pressure gradient is high, i.e., a large pressure change per unit of time is observed, the electric motor 5 is actuated at a high speed to prevent potential damage. If, on the other hand, the pressure gradient is low, a low speed of the electric motor 5 is sufficient.

[0042] In any case, depending on the pressure gradient detected by the pressure sensor 7, the electromechanical drive 5 can be controlled accordingly and its speed varied via the control unit 8. Such a detailed evaluation not only of the position of the plunger 6, but also with regard to its positioning movement, taking into account the positioning speed, as well as

[0043] Adjusting speeds was not possible with the current state of the art.

[0044] Reference symbol list

[0045] Door leaf 1

[0046] Motor vehicle body 2

[0047] Housing 3, 4

[0048] Electronic housing 4

[0049] Drive 5

[0050] Pestle 6

[0051] Sensor 7

[0052] Control unit 8

[0053] Membrane 9

[0054] Seal 10

[0055] Membrane 11

[0056] Membrane 12

[0057] Position sensor 13

[0058] Position sensor 14

[0059] Position sensor 15

[0060] Hollow passage 16

[0061] Gap S

Claims

Patent claims 1. Opening device for a motor vehicle door, comprising a plunger (6), further comprising an electric motor drive (5) for the plunger (6), and comprising at least one sensor (7) for detecting a positioning movement of the plunger (6), wherein the plunger (6) can be moved at least between an extended and a retracted position relative to a housing (3, 4) accommodating the drive (5) and the plunger (6), characterized in that the sensor (7) is designed as a stationary pressure sensor (7) in the sealed housing (3, 4), which detects pressure fluctuations inside caused by a positioning movement of the plunger (6) relative to the housing (3, 4).

2. Device according to claim 1, characterized in that the plunger (6) has a front seal (10) for contact with a motor vehicle body (2) or a door leaf (1) of the motor vehicle door.

3. Device according to claim 1 or 2, characterized in that the plunger (6) is equipped with a hollow passage (16) which communicates with the interior of the housing (3, 4).

4. Device according to claim 3, characterized in that the hollow passage (16) is sealed to the outside and inside of the housing (3, 4) by at least one membrane (11 , 12).

5. Device according to one of claims 1 to 4, characterized in that the housing (3, 4) is divided into a drive housing (3) accommodating the drive (5) and an electronics housing (4) accommodating a control unit (8) and the pressure sensor (7).

6. Device according to claim 5, characterized in that both housing components (3, 4) communicate with each other via a membrane (9).

7. Device according to one of claims 1 to 6, characterized in that at least one position sensor (13) is additionally provided on the plunger (6).

8. Method for operating a lifting device for a motor vehicle door, in particular for operating a lifting device according to one of claims 1 to 7, wherein a plunger (6) is moved by means of an electric motor drive (5) at least between an extended and retracted position relative to a housing (3, 4) accommodating the drive (5) and the plunger (6), and wherein positioning movements of the plunger (6) in the form of pressure fluctuations caused inside the housing (3, 4) are detected by means of a sensor (7) designed as a stationary pressure sensor (7) in the sealed housing (3, 4).

9. Method according to claim 8, characterized in that the pressure sensor (7) detects both pressure changes inside the housing (3, 4) associated with an actuating movement of the plunger (6) with its seal (10) in contact with the motor vehicle body (2) or the door leaf (1) of the motor vehicle door, and those that occur when the seal (10) and thus the plunger (6) is detached from the motor vehicle body (2) or the door leaf (1).

10. Method according to claim 8 or 9, characterized in that the drive (5) is equipped with an overload spring which allows a backward movement of the extended plunger (6) in the direction of its retracted position, wherein, depending on the pressure change detected by the pressure sensor (7) during the backward movement of the plunger (6), the drive (5) retracts the plunger (6) at a correspondingly adjusted speed.

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