Motor vehicle lock

Abstract

The invention relates to a motor vehicle lock and in particular a motor vehicle door lock, preferably a motor vehicle side door lock. The basic design of the motor vehicle lock is equipped with a locking mechanism (1, 2) substantially consisting of a rotary latch (1) and at least one pawl (2) as locking mechanism components (1, 2). Moreover, at least one sensor (3, 4) for sensing the position of the rotary latch (1) and / or of the pawl (2) is implemented. According to the invention, at least two differently designed sensors (3, 4) are provided, wherein in each case, one sensor (3) which has a diagnostic capability is designed to carry out scans that are sensitive to functionality, and one sensor (4) which does not have a diagnostic capability is designed to carry out scans that are not based on functionality.

Description

[0001] Description

[0002] Motor vehicle lock

[0003] The invention relates to a motor vehicle lock, in particular a motor vehicle door lock, preferably a motor vehicle side door lock, with a locking mechanism consisting essentially of a rotary latch and at least one pawl as locking mechanism components, and with at least one sensor for detecting the position of the rotary latch and / or the pawl.

[0004] Motor vehicle locks, and in particular motor vehicle side door locks or motor vehicle tailgate locks, are often equipped with additional functions in addition to their original locking function or are integrated with such additional functions. For example, an additional closing aid can be provided. This closing aid can be used to initiate a closing process of the motor vehicle door or vehicle tailgate equipped with the respective motor vehicle lock. This generally requires that the closing process is started when the locking mechanism assumes a pre-locking position. The assumption of the pre-locking position is detected by the sensor for detecting the position of the rotary latch and / or the pawl.

[0005] Other functions are also conceivable in this context, such as an anti-theft function. This anti-theft function is activated as soon as the locking mechanism has reached its main locking position. In this case, too, the position is detected using the sensor. This has proven itself in principle and is widely used in practice.

[0006] For example, DE 10 2019 107 572 A1 discloses such a motor vehicle lock, in which a sensing element is additionally provided between the sensor and the associated locking component. The sensing element is designed to sense the locking position of the pawl on the one hand and the rotary latch on the other. Any deviation of at least one locking component from its closed position triggers a signal from the associated sensor. The sensor can be a Hall sensor, which reacts to the movements of an associated and opposing permanent magnet. In principle, a tactile microswitch can also be used in this position.

[0007] DE 102021 117277 A1 concerns a control arrangement for operating a motorized flap assembly of a motor vehicle. A closing drive is also provided. The control arrangement can determine the flap position and / or flap speed using a displacement sensor arrangement associated with the flap drive, the closing drive, and / or the flap. The displacement sensor arrangement can be configured as a Hall sensor arrangement and / or as a position switch, in particular a latch switch.

[0008] DE 10 2020 101 428 A1 concerns an actuating device for a motor vehicle lock. It features a lever arrangement equipped with two actuating levers that are spring-biased and pivotally connected to each other. A sensor is also provided to detect the relative movement of the two levers. The sensor can be a non-contact sensor that operates inductively and is preferably designed as a Hall sensor.

[0009] The state of the art has generally proven itself when it comes to querying individual positions of the locking mechanism. Both switches and Hall sensors are used for this purpose. Hall sensors have the fundamental advantage that they are, in principle, capable of diagnosis or can be designed for this purpose. This means that the functional reliability of the Hall sensor can be checked before or during operation. Such self-checking is generally not possible with a conventional switch or microswitch. This explains why Hall sensors are expensive, whereas switches and especially microswitches are available at low cost. However, there have so far been no approaches to cost-optimizing the sensor technology in such a motor vehicle lock in this direction.

[0010] Accordingly, the invention is based on the technical problem of further developing such a motor vehicle lock and in particular a motor vehicle door lock in such a way that a cost-optimized sensor system is monitored and available.

[0011] To solve this technical problem, a generic motor vehicle lock is characterized within the scope of the invention in that at least two differently designed sensors are provided, wherein a diagnostic-capable sensor is or are configured for function-sensitive scanning and a non-diagnosable sensor is or are configured for function-independent scanning.

[0012] According to the invention, therefore, a (single) sensor is not used to detect the position of the rotary latch and / or the pawl. Instead, two sensors are used. This is usually done in such a way that one sensor serves as the main locking sensor and another sensor as the pre-locking sensor. The main locking sensor can be used to detect the assumption of a main locking position of the locking mechanism implemented according to the invention, which essentially consists of a rotary latch and at least one pawl as locking components. In contrast, the pre-locking sensor serves to detect a corresponding pre-locking position of the locking mechanism.

[0013] According to a particularly advantageous embodiment, the overall procedure is such that the diagnosable sensor is designed as the main stop sensor and the non-diagnosable sensor as the pre-stop sensor. The term “diagnosable sensor” refers to a sensor that is designed and capable of self-testing. For this purpose, both sensors are usually connected to a control unit, which at least initiates the self-test of the diagnosable sensor. During this self-test of the diagnosable sensor, not only is its basic functionality checked, but also the functionality of a signal line outgoing from the sensor to the control unit. In addition, the proper power supply to the sensor is checked in connection with this self-test.

[0014] The usual procedure is to subject the diagnostic-capable sensor to a self-test in an unloaded state. Alternatively or additionally, the self-test can also be performed each time the sensor is switched on. This provides a significant increase in safety and simultaneously leads to the cost savings pursued by the invention. The increased safety is explained by the fact that the self-test, which is performed, for example, each time the sensor is switched on, ensures that malfunctions or false signals from the sensor are virtually eliminated. This is particularly relevant given that the diagnostic-capable sensor is designed for function-sensitive scanning.

[0015] According to the invention, "function-sensitive scanning" refers to a scanning process by the diagnostic-capable sensor that is particularly relevant to the function of the motor vehicle lock. This also applies, and in particular, to security requirements. For example, a function-sensitive scanning corresponds to the locking mechanism scanned by the sensor having safely assumed its main locking position. This is particularly important for a closing drive with a closing aid.

[0016] Activating the closing aid generally moves the locking mechanism into an overtravel position before assuming the main locking position. This allows the pawl to securely engage the rotary latch in this overtravel position, blocking the rotary latch properly in the main locking position. Only then can the locking mechanism unfold its full effect, particularly in the event of a crash, and prevent a vehicle door or tailgate equipped with it from accidentally opening, for example. Furthermore, the functionality of additional safety features such as airbags, belt tensioners, etc. is usually linked to the secure engagement of the main locking position.

[0017] This means that a flawless and credible main locking signal is not only relevant with regard to the reliable operation of the motor vehicle lock according to the invention, but also represents an essential safety criterion. Only the reliable assumption of the main locking position ensures optimal protection of car occupants.

[0018] In contrast, the "function-independent scanning" of the non-diagnostic sensor is a scanning process that has no fundamental significance for security or does not call into question the general functionality of the vehicle lock. For example, such a function-independent scanning is simply an on / off signal for the previously mentioned control unit. Should the non-diagnostic sensor malfunction at this point, the control unit is usually still switched on or, for example, a wake-up function is initiated for the control unit. The basic functionality of the vehicle lock is therefore not called into question.

[0019] If, for example, the non-diagnostic sensor or pre-locking sensor does not correctly sense the pre-locking position assumed by the locking mechanism, this only results in the closing drive or closing aid in the example case not receiving any input from the control unit. An operator must then, for example, manually ensure that the corresponding vehicle door or vehicle tailgate is completely closed and reaches the main locking position. Consequently, even a failure or malfunction of the non-diagnostic sensor does not change the basic functionality of the vehicle lock according to the invention, because proper security depends on the main locking position being assumed, which in turn must be correctly and verifiably assumed with the help of the diagnosable sensor as the main locking sensor.

[0020] In this way, the required security and functionality of the vehicle lock is ensured overall, while at the same time maintaining a particularly cost-effective design. This is because the non-diagnostic sensor is used for function-independent scanning, for example, as a pre-lock sensor to detect when the locking mechanism has entered its pre-locking position. For example, entering the pre-locking position corresponds to the fact that this triggers the operation of the closing aid. Alternatively or additionally, entering the pre-locking position ensures that the control unit is "woken up" because it previously entered "sleep mode" when the locking mechanism was open. Even in this case, malfunctions related to the wake-up function are generally acceptable and are not particularly safety-relevant.

[0021] If the control unit's wake-up function hasn't been initiated and the control unit consequently remains unloaded, in the example case, either the closing aid won't operate and will close a corresponding wing of the vehicle door or hatch all the way to the main stop. Or, for example, an anti-theft function won't be implemented, which then leads to a malfunction signal, but doesn't call into question the fundamental mechanical functionality of the vehicle lock according to the invention.

[0022] In particular, this mechanical functionality and thus the safety aspect for the vehicle occupants is reflected because the main locking sensor is responsible for sensing the main locking position. This sensor is designed as a diagnostic-capable sensor and is therefore subjected to regular self-testing with regard to its functionality. In this way, the motor vehicle lock according to the invention combines, on the one hand, reliable functionality, particularly with regard to sensing the main locking position, with, on the other hand, a cost-effective design, because the non-diagnostic and therefore cost-effective sensor is used for the function-independent sensing or checking of positions that are unimportant for function or mechanical safety.

[0023] The invention is also based on the realization that, for example, the assumption of the pre-locking position in a motor vehicle is usually additionally sensed by door contact switches, which generate a corresponding warning signal if the corresponding motor vehicle door does not assume its fully closed position. This represents the key advantages.

[0024] According to an advantageous embodiment, the diagnosable sensor is designed with at least two poles. One pole serves for the power supply. The second pole serves for signal output and / or diagnostics. Furthermore, it has proven useful in this context if the diagnosable sensor is designed as a Hall sensor or switch whose electrical connections are connected to at least one electrical resistor. If the diagnosable sensor is designed as a Hall sensor, the control unit applies a voltage simulating a magnetic field to the sensor in question for self-testing. Furthermore, the control unit samples the sensor's response, including the signal path, to perform the self-test described. This will be explained in more detail with reference to the description of the figures.

[0025] The non-diagnostic sensor is usually a switch without resistors, which is designed particularly cost-effectively. The control unit, in turn, can be configured to activate an anti-theft device and / or a closing aid and / or a retraction unit. In the case of a retraction unit, the signals from the pre-locking sensor and main-locking sensor can be used again. This is because such a retraction unit is generally only activated and ensures that the leaf of the vehicle door or tailgate is raised when both the pre-locking position and the main-locking position of the locking mechanism have been left.

[0026] In any case, the motor vehicle lock according to the invention is, on the one hand, particularly secure in design because, in particular, the assumption of the main locking position is reliably sensed. This is ensured by the diagnostic-capable sensor as the main locking sensor. As a result, any false activations of, for example, airbags, a belt tensioner, etc., can be avoided because the main locking sensor is regularly subjected to the self-test described above, and malfunctions or false signals can be ruled out by design. At the same time, and on the other hand, a particularly cost-effective design is observed because the pre-locking sensor is typically configured as a non-diagnostic sensor and, in this case, is usually configured as a particularly simple and cost-effective switch, in particular a microswitch.The assumption of the pre-locking position is of secondary importance with regard to safety aspects and the proper functioning of the motor vehicle lock according to the invention.

[0027] The invention is explained in more detail below with reference to a drawing which merely represents an exemplary embodiment; in the drawings:

[0028] Fig. 1 shows the motor vehicle lock according to the invention in a schematic overview,

[0029] Fig. 2A and 2B show two different variants of a diagnosable switch and

[0030] Fig. 3 shows a Hall sensor capable of diagnosis schematically.

[0031] Figures 1A and 1B show a motor vehicle lock equipped with a locking mechanism 1, 2. In the exemplary embodiment, the motor vehicle lock is a motor vehicle door lock, and more specifically, a motor vehicle side door lock. This is, of course, only an example and is in no way restrictive. In principle, it could also be a motor vehicle tailgate lock. The locking mechanism 1, 2 is in turn composed of a rotary latch 1 and a pawl 2 interacting therewith in the usual manner. In principle, more than one pawl 2 can also be implemented, although this is not shown. The rotary latch 1 and the pawl 2 are respective locking mechanism components 1, 2.

[0032] In addition, at least one sensor 3, 4 is provided for sensing the position of the rotary latch 1 and / or the pawl 2. According to the exemplary embodiment, two sensors 3, 4 are implemented, namely a main locking sensor 3 and a pre-locking sensor 4. Both sensors 3, 4 are connected to a common control unit 5 according to the exemplary embodiment. Also connected to the control unit 5 is a closing drive or closing aid 6 (only indicated) with the aid of which the rotary latch 1 is transferred from the pre-locking position shown in Fig. 1A to the main locking position as shown in Fig. 1B.

[0033] According to the invention, the two sensors 3, 4 are designed differently. In fact, the main locking sensor 3 according to the exemplary embodiment is configured as a diagnostic-capable sensor 3 for functionally sensitive scanning of the locking mechanism 1, 2. This means that the precise, reproducible, and long-lasting functionality of the diagnostic-capable sensor 3 is essential and safety-relevant for the function of the motor vehicle lock and, in particular, its locking mechanism 1, 2. Specifically, and in the exemplary embodiment, this means that the main locking sensor 3 must be able to reliably detect the assumption of the main locking position as shown in Fig. 1B. For this purpose, the diagnostic-capable sensor or main locking sensor 3 in question is subjected to a self-test.

[0034] The self-test of the diagnostic-capable sensor 3 typically occurs in its unloaded state and regularly during each power-on process. For this purpose, the diagnostic-capable sensor 3 is designed with at least two poles according to the exemplary embodiment. In fact, three poles are implemented according to the exemplary embodiment.

[0035] Based on the specific embodiment of the diagnosable sensor 3 as shown in Fig. 3, one can first of all recognize a Hall sensor 10, which reacts to approaches of the rotary latch 1 or an edge 1a of the rotary latch 1. For this purpose, a permanent magnet may additionally be provided in or on the edge 1a. In addition, the Hall sensor 10 is connected to a series resistor 8 and a capacitor 9. Furthermore, a diode 7 is provided, which is designed, for example, as a Schottky diode. The diagnosable sensor 3 is supplied with the required electrical energy with the aid of a current source 11. The current source 11 is a vehicle-mounted battery, only indicated in Fig. 3. The diagnosable sensor 3 is connected to the control unit 5 via two external connections 12, 13.

[0036] With correct polarity reversal and continuous connection of the power source 11, the diagnostic-capable sensor 3 in the illustrated embodiment has a current consumption of approximately 10 to 20 mA in the activated state. The activated state corresponds to the rotary latch 1 being in the main locking position as shown in Fig. 1B, and the Hall sensor 10 being actuated accordingly by the approach of the edge 1a.

[0037] In contrast, the deactivated state of the Hall sensor 10 and thus of the diagnosable sensor 3 corresponds to the current consumption dropping to values ​​well below 10 mA, for example 5 mA and less down to 2 mA. If a short circuit to ground is observed, the current consumption is above 20 mA. A short circuit to battery voltage leads to a current consumption of less than 2 mA. Consequently, the different functional states, namely the activated Hall sensor 10, the deactivated Hall sensor 10 and any short circuits as well as reversed polarity can be determined, with the control unit 5 measuring the respective current consumption of the diagnosable sensor 3 and deriving the functional state from this. This means that with the help of the diagnosable sensor 3, a function-sensitive scanning of the locking mechanism 1, 2 is possible in the specific example case, namely the clear differentiation between the pre-locking position in Fig.1A and the main locking position according to Fig. 1B. A current consumption between 10 mA and 20 mA is interpreted as activation of the Hall sensor 10 and, accordingly, the assumption of the main locking position of the rotary latch 1. If, on the other hand, the current consumption is between 2 mA and 5 mA, this corresponds to the deactivation of the Hall sensor 10 and consequently of the diagnostic-capable sensor 3 as a whole. Then, for example, the pre-locking position or an open position is assumed by the rotary latch 1. A current consumption of more than 20 mA or less than 2 mA is interpreted as a short circuit.

[0038] Alternatively or additionally, the diagnosable sensor 3, as shown in Fig. 3, can also be subjected to a voltage simulating a magnetic field for self-testing using the control unit 5. In this case, the control unit 5 ensures that the Hall sensor 10 is supplied with voltage via the voltage supply 11 and detects the reaction of the Hall sensor 10, including the signal path, by measuring the current consumption via the two poles or connections 12, 13 using the control unit 5. In any case, the diagnosable sensor 3 or the Hall sensor 10 can be subjected to a self-test using the control unit 5 in the manner described.

[0039] Another embodiment of a diagnostic-capable sensor 3 is shown in Figs. 2A and 2B. Here, it can be seen that a contact device 14 is implemented, which has two electrical terminals 15, 16 that are electrically connected to one another via a high-resistance resistor R1. Furthermore, a second high-resistance resistor R2 is provided between the second terminal 16 and a further third terminal 17. In the variant according to Fig. 2B, the two resistors R1 and R2 are implemented in a plastic body that is designed to be conductive. However, the functionality corresponds to the basic principle shown in Fig. 2A.

[0040] If the contact device 14 is in the position shown in Fig. 2A or 2B, the resistance value across the two terminals 15, 16 is zero. For this purpose, the three terminals 15, 16, 17 are again connected to the control unit 5. However, if the resistance value across the two terminals 15, 16 is as high as the high-ohmic resistor R1 specifies, the contact device 14 is open. In this case, the resistance value between the terminals 15 and 17 is zero. If, on the other hand, a resistance value of zero is observed between the contact points 15 and

[0041] 16 and 16 and 17 each observe infinitely large resistances, there is a fault in the supply line or in the contacting of the contact device 14.

[0042] The diagnostic sensor 3 as shown in Figs. 2A and 2B is a switch whose electrical connections 15, 16,

[0043] 17 according to the exemplary embodiment are connected to at least one electrical resistor R1, R2. In contrast, a non-diagnostic sensor 4 in the embodiment as a switch without resistors does not require the resistors R1, R2 in question, namely, it is reduced to the contact device 14 in the exemplary embodiment according to Figs. 2A and 2B.

[0044] As already explained in the introduction, the control unit 5 is configured to activate an anti-theft device, or rather the closing aid 6 shown in Fig. 1. In the case of an anti-theft device, the control unit 5 evaluates the signal from the non-diagnostic sensor 4 upon reaching the pre-locking position shown in Fig. 1A in such a way that this signal is used as a wake-up signal for the control unit 5. At the same time, in this example, the signal from the pre-locking sensor 4 causes the closing aid 6 to be activated with the help of the control unit 5, which then pivots the rotary latch 1 around its axis in the indicated clockwise direction during the transition from the position shown in Fig. 1A to Fig. 1B. This closing process is continued up to an over-stroke position beyond the main locking position shown in Fig. 1B, so that the pawl 2 can securely engage.The locking mechanism 1, 2 then moves into the main locking position as shown in Fig. 1 B. Reaching the main locking position is reported to the control unit 5 by means of the diagnostic-capable sensor 3 or the main locking sensor 3 and ensures that the closing aid 6 is no longer energized.

[0045] At the same time, reaching the main locking position according to Fig. 1 B corresponds to the fact that the anti-theft protection is activated and safety devices not shown are activated when the vehicle moves in the event of a crash.

[0046] List of reference symbols

[0047] Lock 1 , 2

[0048] Rotary latch 1

[0049] Edge 1 a

[0050] Pawl 2

[0051] Sensors 3, 4

[0052] Pre-locking sensor 4

[0053] Control unit 5

[0054] Closing aid 6

[0055] Diode 7

[0056] Hall sensor 7

[0057] Series resistor 8

[0058] Capacity 9

[0059] Hall sensor 10

[0060] Power source 11

[0061] External connections 12, 13

[0062] Contact device 14

[0063] Contact points 15

[0064] Connections 15, 16

[0065] Connection 17

[0066] Resistor R1 , R2

Claims

Patent claims 1. Motor vehicle lock, in particular motor vehicle door lock, with a locking mechanism (1, 2) essentially consisting of a rotary latch (1) and at least one pawl (2) as locking mechanism components (1, 2), and with at least one sensor (3, 4) for querying the position of the rotary latch (1) and / or the pawl (2), characterized in that at least two differently designed sensors (3, 4) are provided, wherein a diagnostic-capable sensor (3) is set up for function-sensitive scanning and a non-diagnostic-capable sensor (4) is set up for function-independent scanning.

2. Motor vehicle lock according to claim 1, characterized in that the diagnostic sensor (3) is subjected to a self-test in the unloaded state.

3. Motor vehicle lock according to claim 1 or 2, characterized in that the self-test is carried out each time the sensor (3) is switched on.

4. Motor vehicle lock according to one of claims 1 to 3, characterized in that both sensors (3, 4) are connected to a control unit (5) which initiates at least the self-test of the diagnosable sensor (3).

5. Motor vehicle lock according to one of claims 1 to 4, characterized in that the diagnostic sensor (3) is designed with at least two poles, one pole serving for power supply and the other pole for signal output and / or diagnosis.

6. Motor vehicle lock according to one of claims 1 to 5, characterized in that the control unit (5) applies a voltage simulating a magnetic field to the diagnostic sensor (3) for self-testing and scans the reaction of the sensor (3) including the signal path.

7. Motor vehicle lock according to one of claims 1 to 6, characterized in that the diagnostic sensor (3) is designed as a Hall sensor (10) or contains such a sensor or is designed as a switch whose electrical connections (15, 16, 17) are connected to at least one electrical resistor (R1, R2).

8. Motor vehicle lock according to one of claims 1 to 7, characterized in that the non-diagnostic sensor (4) is designed as a switch without resistors.

9. Motor vehicle lock according to one of claims 1 to 8, characterized in that the diagnostic sensor (3) is designed as a main locking sensor (3) and the non-diagnostic sensor (4) is designed as a pre-locking sensor (4).

10. Motor vehicle lock according to one of claims 1 to 9, characterized in that the control unit (5) is designed to activate an anti-theft device and / or a closing aid (6) and / or a setting unit.

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