Method for operating a locking device for a vehicle door

Abstract

The invention relates to a method for operating a locking device (2) for a vehicle door (4), comprising an electric lock drive (20) for actuating a lock mechanism (12), a release element (10) for triggering the lock drive (20), and a temperature sensor (24) for detecting a device temperature (T) of the locking device (2), wherein when the release element (10) is actuated, the release element (10) is monitored with regard to further actuations, wherein in the case of further actuations of the release element (10), an actual number (N) of actuations is detected and compared with a maximum number (M) of permissible actuations determined as a function of a detected device temperature (T), with which the lock drive (20) may be repeatedly triggered, and wherein a triggering of the lock drive (20) is blocked if the actual number (N) reaches or exceeds the maximum number (M).

Description

[0001] The invention relates to a method for operating a locking device for a vehicle door, comprising an electric lock motor for actuating a locking mechanism and a release element for triggering the lock motor. The invention further relates to a locking device operated according to the method and a vehicle door with such a locking device.

[0002] To secure the vehicle interior, vehicle doors are regularly equipped with locking devices designed as door locks, which allow the vehicle door to be reversibly locked and unlocked in a closed position. For locking and unlocking, such locking devices typically include a locking mechanism with locking elements (latch, latch, striker, etc.).

[0003] In modern vehicles, such locking devices are increasingly motor-driven to enhance ease of use and security. These motor-driven or electric locking devices feature an electric drive, for example, with an electromagnet or an electric motor, which, when triggered, actuates the locking mechanism, thus locking or unlocking the device. The drive is typically integrated into the vehicle's central locking system via electronic lock components, enabling remote operation of the lock or drive via radio remote controls or keyless entry systems.

[0004] To ensure reliable and safe locking and unlocking of the vehicle door even at high ambient temperatures, it is necessary to protect the lock drive from overheating.

[0005] In this and the following, "overheating" refers specifically to a thermal overload of the locking mechanism, particularly the lock actuator, where the operating temperature rises above a safe or permissible range. Such overheating can lead to damage or destruction of the locking mechanism or the lock actuator, preventing the vehicle door from locking or unlocking properly.

[0006] Since an electric current flows through the lock actuator, particularly through a motor winding or a solenoid coil, when the lock actuator is triggered, ohmic losses occur within the actuator, which increase its operating temperature. Multiple triggering events, where the lock actuator is triggered several times within a short period, are particularly critical in this regard.

[0007] To protect the lock actuator, the number of possible repeated releases is limited. A fixed number is specified for all temperature ranges. Since at high temperatures, such as +80 °C, even a few consecutive releases can lead to overheating of the lock actuator, the permissible number of releases is generally designed with these high temperature values ​​in mind. Limiting the permissible multiple releases to this number is also applied to lower temperature ranges, even though a greater number of consecutive releases might be possible at such temperatures before the lock actuator overheats. This negatively impacts user convenience.

[0008] The invention is based on the objective of providing a particularly suitable method for operating a locking device. In particular, user comfort when operating the locking device is to be increased. The invention is further based on the objective of providing a particularly suitable locking device and a particularly suitable vehicle door.

[0009] With regard to the method, the problem is solved according to the invention by the features of claim 1, with regard to the locking device by the features of claim 7, and with regard to the vehicle door by the features of claim 9. Advantageous embodiments and further developments are the subject of the dependent claims.

[0010] The advantages and features mentioned with regard to the process are analogous to those of the locking mechanism and / or the vehicle door, and vice versa. The conjunction "and / or" here and in the following is to be understood as meaning that the features linked by this conjunction can be either combined or alternative to each other.

[0011] If process steps are described below, advantageous designs for the locking device result in particular from the fact that it is designed to perform one or more of these process steps.

[0012] The method according to the invention is intended for operating a locking device for a vehicle door and is suitable and designed for this purpose.

[0013] The term "vehicle door" is used here and in the following to refer specifically to a movable cover or locking element of the vehicle that allows or prevents access to the interior of the vehicle. The vehicle door is typically connected to the vehicle frame via hinges or sliding mechanisms and can be opened and closed manually or automatically. The term "vehicle door" is used here and in the following in a broad sense and also includes, in particular, gullwing doors, side doors, rear doors, tailgates, trunk lids, and hoods.

[0014] The locking device includes a locking mechanism for locking and unlocking the vehicle door. This locking mechanism includes, for example, a locking bar with at least one movable locking element, which can be adjusted between an open position (unlock position) and a locked position (lock position) during the locking or unlocking process. The locking device also includes an electric drive unit for operating the locking mechanism. This drive unit is coupled to the locking mechanism, specifically to the movable locking element, to move it for locking and unlocking.

[0015] The locking device also includes a release element for activating the lock drive. Upon release, the lock drive is activated, thus actuating the lock mechanism or adjusting the locking element between the open and locked positions. Here and in the following, a "release element" refers specifically to a device which, upon release or actuation, triggers an electronic locking or unlocking action by the lock drive.

[0016] The triggering element is, for example, a (transmitter) receiver for a radio signal from a remote interaction unit, which allows a vehicle user to operate the locking mechanism contactlessly by pressing a button. The triggering element is actively controlled and actuated by the remote interaction unit that generates the radio signal. Upon receiving a corresponding radio signal, the triggering element activates the lock mechanism without requiring manual operation of the locking device itself. In this case, the remote interaction unit is typically a separate component of the locking mechanism. For example, the remote interaction unit could be a radio remote control.

[0017] Alternatively, the triggering element can be implemented, for example, as a keyless entry system, in which the lock drive is automatically triggered when a corresponding (remote) key is within a predetermined distance of the vehicle or the locking mechanism, without requiring any (active) manual operation by the vehicle user. In this case, the triggering element is passively activated by the approach of the key.

[0018] Alternatively, the triggering element can also be designed, for example, as a manually operated door locking switch in the vehicle interior, such as on an interior trim panel of the vehicle door or on a center console (dashboard), which triggers the lock drive when actuated.

[0019] According to the invention, the locking device additionally includes a temperature sensor by means of which the device temperature of the locking device can be detected. In particular, the temperature sensor detects the temperature of the lock drive (drive temperature). The temperature sensor is used here especially for temperature monitoring with regard to overheating of the lock drive.

[0020] As per the procedure, upon initial actuation of the release element, it is monitored for subsequent actuations. This means monitoring whether multiple actuations, i.e., repeated or consecutive actuations, of the release element occur. For example, this is done by monitoring whether at least one further actuation of the release element occurs within a predefined time period.

[0021] As part of this monitoring process, the actual number of activations is determined or recorded. For example, a counter is incremented with each activation, and the counter is reset to an initial value, such as zero (0), after a predetermined period.

[0022] In the event of multiple actuations, where the release element is activated more than once within a specified period, the actual number of actuations is compared with a maximum number of permissible actuations, determined based on a measured device temperature. This maximum number of actuations allows the lock actuator to be triggered repeatedly. The maximum number of actuations is dimensioned such that, with a corresponding number of actuations, overheating of the lock actuator is essentially prevented. In other words, trigger-induced overheating of the lock actuator during multiple actuations at the maximum number is sufficiently improbable. The specific probability considered sufficient and its precise magnitude are initially irrelevant. This can be determined, for example, from historical lock data or from relevant tests or trials.Different maximum numbers may result depending on the vehicle doors, lock drives, operating and environmental conditions or application scenarios.

[0023] The procedure prevents the lock actuator from being triggered if the actual number of activations reaches or exceeds the maximum number. This means that if the release element is activated beyond the maximum number, no further activation of the lock actuator will occur. This results in a particularly suitable method for operating the locking device.

[0024] According to the invention, the permissible maximum number of multiple actuations is thus determined or calculated based on a detected or measured device or drive temperature. In other words, the invention provides that the maximum number of multiple actuations is varied, i.e., changed or scaled, based on the current actual temperature of the locking device or the lock drive. Therefore, according to the invention, there is no single fixed maximum number of actuations value stored for all temperature ranges; instead, a temperature-dependent maximum number of actuations value is dynamically determined during lock operation.

[0025] For example, it is conceivable that the device temperature is continuously monitored, i.e., independently of any actuation of the triggering element, and a current maximum number of actuations is determined, so that the maximum number is already present upon the first actuation of the triggering element. Preferably, the device temperature is recorded after the first actuation, and the maximum permissible number of actuations at that device temperature is determined, which is then used to limit the number of multiple actuations. In other words, the temperature sensor is read upon the first actuation of the triggering element, and the permissible maximum number of actuations for that device temperature is determined based on the recorded temperature value. The number of multiple or consecutive actuations is then limited to the maximum number within a predetermined time period.

[0026] The method according to the invention ensures, firstly, that at specified maximum temperatures the electrical components of the locking device, in particular the lock drive and / or the electronics controlling it, are protected against overheating by limiting or restricting multiple actuations. Secondly, it allows the vehicle user to perform the locking function (unlocking / locking) more frequently in succession at lower temperatures, for example at room temperature, thus increasing user-friendliness.

[0027] For example, the maximum number of operations at room temperature is 25, allowing the vehicle user to lock and unlock the device up to 25 times consecutively if needed. At device temperatures of 80 °C or higher, the maximum number of operations is limited to, for example, only three (3).

[0028] This method thus provides a particularly suitable anti-play function for the locking mechanism. Here and in the following, "anti-play function" refers specifically to a feature of the locking mechanism that prevents the lock drive from being triggered repeatedly within a short period of time by repeated or playful activation of the release element. This protective function aims to prevent the misuse or unnecessary activation of the locking mechanism, for example by children, in order to avoid excessive wear and tear and the associated risk of overheating or potential damage.

[0029] The lock drive can, for example, include an electromagnet that actuates a magnetic locking element of the lock mechanism. This method prevents overheating of the electromagnet's coil winding. In a preferred embodiment, the lock drive includes an electric motor (lock motor). The electric lock drive is thus designed as an electromechanical lock drive. This allows for a higher degree of precision in the actuation of the lock mechanism. In particular, reliable power transmission is ensured, guaranteeing that the lock mechanism is reliably locked or unlocked. Furthermore, the use of a lock drive is more energy-efficient, as the lock motor only requires power during the actuation of the lock mechanism.An electromechanical adjustment of the lock mechanism also results in lower noise levels, thus further improving the user comfort of the lock device.

[0030] In an advantageous embodiment, the release of the lock actuator is blocked for a predetermined period if the actual number of activations reaches or exceeds the maximum number. This period is dimensioned such that the lock mechanism or the lock actuator can cool down sufficiently to minimize the risk of overheating upon subsequent activation. This period is therefore, in particular, a minimum duration before the lock actuator can be released again without risk of overheating.

[0031] The duration is pre-characterized and stored, for example, based on past lock data or from corresponding tests or trials. Different durations are stored for various vehicle doors, lock drives, operating and environmental conditions, or application scenarios. Preferably, the duration is varied based on the recorded device temperature and / or maximum number of locks. In other words, different durations are stored depending on the locking condition (device temperature, maximum number of locks). Alternatively, a mathematical formula for determining the duration based on the recorded device temperature and / or maximum number of locks is stored.

[0032] In an additional or alternative version, the lock actuator's release is blocked when the maximum number of activations is reached or exceeded, until the device temperature reaches or falls below a predefined threshold. This means that after the release is blocked, the device temperature is continuously or periodically measured and compared to the threshold. This ensures that the lock actuator can only be released again once it has cooled down sufficiently. Thus, the risk of overheating is reliably reduced or completely eliminated.

[0033] The threshold is dimensioned to minimize the risk of overheating upon re-triggering. This threshold is pre-characterized and stored based on past lock data or relevant tests and trials. Different thresholds are stored for various vehicle doors, lock drives, operating and environmental conditions, and application scenarios. Preferably, the threshold is varied based on the detected device temperature and / or maximum number of locks. In other words, different thresholds are stored depending on the locking condition (device temperature, maximum number of locks). Alternatively, a mathematical formula for determining the threshold based on the detected device temperature and / or maximum number of locks is stored.

[0034] According to the method, for example, a variable number of maximum actuations is defined in a control unit or controller of the lock drive, depending on the detected device temperature. In a preferred embodiment of the method, the maximum number is reduced with increasing device temperature. For example, at high device temperatures, such as +80 °C, only a small number of actuations, e.g., 3, are possible, whereas at lower device temperatures, such as room temperature, more actuations, e.g., 25, are permitted.

[0035] To determine the maximum number of cycles based on the device temperature, it is conceivable, for example, that a corresponding mathematical formula or characteristic curve is stored. In a preferred embodiment, the maximum number is determined using a stored lookup table in which temperature values ​​for the device temperature are assigned to a respective permissible number of multiple cycles or maximum number of cycles.

[0036] Preferably, the expected operating temperature range of the locking device is divided into a number of temperature ranges, with each temperature range assigned a value representing the maximum number of entries. This results in a particularly memory-efficient table.

[0037] For an application in a side-door lock, the operating temperature range is, for example, divided into four temperature ranges. Up to +40 °C, 25 consecutive actuations are permitted. In a temperature range between +40 °C and +70 °C, 15 consecutive actuations are possible. Between +70 °C and +80 °C, the maximum number is, for example, 5, with a limit of 3 above +80 °C.

[0038] The locking device according to the invention is designed, suitable, and configured for a vehicle door. The locking device is thus designed as a door locking system.

[0039] The locking device comprises a locking mechanism with an electrically coupled drive for actuating the locking mechanism. The drive and the locking mechanism are, for example, designed as a door lock, in particular as a side door lock.

[0040] The locking device further comprises a release element for triggering the lock drive and a temperature sensor for detecting the device temperature of the locking device. The temperature sensor is preferably integrated into the door lock, particularly into the lock drive. According to the invention, a controller (i.e., a control unit) is also provided, which is coupled to the lock drive, the release element, and the temperature sensor via signal transmission. This results in a particularly suitable locking device.

[0041] The controller is, for example, designed as the central control electronics for a vehicle's central locking system. However, it is equally conceivable that the controller is located decentrally within the door lock.

[0042] The controller is generally configured – programmatically and / or circuit-wise – to carry out the method according to the invention described above. Specifically, the controller is configured to detect actuation of the release element and to monitor the release element with regard to further actuations. In the event of further actuations of the release element, the actual number of actuations is recorded and compared with a maximum number of permissible actuations, determined as a function of a detected device temperature, with which the lock drive may be repeatedly triggered. Furthermore, the controller blocks the release of the lock drive if the actual number of actuations reaches or exceeds the maximum number.

[0043] In a preferred embodiment, the controller is formed, at least in its core, by a microcontroller comprising a processor and a data memory. The functionality for carrying out the method according to the invention is implemented programmatically in the form of operating software (firmware), so that the method—optionally in interaction with a vehicle user—is carried out automatically when the operating software is executed in the microcontroller. Alternatively, within the scope of the invention, the controller can also be formed by a non-programmable electronic component, such as an application-specific integrated circuit (ASIC) or an FPGA (field-programmable gate array), in which the functionality for carrying out the method according to the invention is implemented by circuitry.

[0044] In a preferred embodiment, the lock drive incorporates an electric motor as the drive unit. This results in a particularly reliable and quiet door lock.

[0045] The vehicle door according to the invention is designed, suitable, and equipped for a motor vehicle and features a locking device as described above. This results in a particularly suitable vehicle door.

[0046] An embodiment of the invention is explained in more detail below with reference to a drawing. The drawing shows, in schematic and simplified representations: Fig. 1 a locking device for a vehicle door, and Fig. 2. A flowchart for a procedure for operating the locking device.

[0047] Corresponding parts and sizes are always marked with the same reference symbols in all figures.

[0048] The Fig. Figure 1 shows a locking device 2 for a vehicle door 4. The vehicle door 4 is, for example, a hinged door, in particular a side door of a motor vehicle.

[0049] The locking device 2 is designed as a door lock system and has a door lock 6 integrated into the vehicle door 4, which in the illustrated embodiment can be unlocked and locked by a motor, in particular by an electric motor.

[0050] The locking device 2 includes a controller 8 as a control unit, which in the illustrated embodiment is, for example, designed as a control unit for a central locking system. Alternatively, the controller 8 is integrated decentrally into the vehicle door or into the door lock 6.

[0051] The locking device 2 further includes a release element 10 for triggering or actuating the central locking mechanism or the door lock 6.

[0052] The door lock 6 has a locking mechanism 12 with a locking element 14, by means of which a locking device 16 of the locking mechanism can be adjusted between a locked position VS and an unlocked position ES. In the locked position VS, the door lock 6 – and thus the vehicle door 4 – cannot be opened, whereas in the unlocked position ES, opening of the vehicle door 4 or the door lock 6 is permitted.

[0053] The locking element 14 is coupled to an electric, in particular electromechanical, lock drive 20 of the door lock 6 by means of a gearbox 18 of the lock mechanism 12. In the embodiment shown, the gearbox 18 is, for example, designed as a worm gear drive, in which the worm gear drives the locking element 14. Alternatively, a lock drive 20 designed as a linear drive with a threaded spindle is also conceivable.

[0054] The lock drive 20 is designed as an electric motor drive. The lock drive 20 thus comprises an electric motor, designated as the lock motor 22, which drives the gearbox 18 or the worm shaft. The lock motor 22 is, for example, a brushless electric motor, which is controlled by an inverter circuit of motor electronics (not shown in detail).

[0055] The controller 8 is designed to control the lock drive 20 or the lock motor 20 with an actuation signal B after receiving a release signal A from the release element 10. Furthermore, the controller 8 is designed to automatically control the lock drive 20 or the lock motor 20 with the actuation signal B as soon as a specific operating state of the vehicle has been reached. The actuation signal B can, for example, be a pulse-width modulated control signal for the inverter circuit of the motor electronics.

[0056] The release element 10 can be triggered, for example, by a lock cylinder, a locking button, or a handle (exterior door handle, interior door handle). In the illustrated embodiment, the release element 10 is specifically designed as a receiver for a radio signal from a radio remote control (not shown in detail).

[0057] The locking device 2, in particular the door lock 6, has a temperature sensor 24 for detecting a device temperature T. The device temperature T is specifically the temperature of the lock drive 20, preferably the lock motor 22. The detected temperature value is sent by the temperature sensor 24 to the controller 8.

[0058] The following is a procedure for operating the locking device 2 based on the Fig. 2 explained in more detail. The method is designed in particular as a temperature-dependent play protection for the door lock 6, which protects the lock drive 20, in particular the lock motor 22, from overheating.

[0059] The procedure is started in process step 26 by actuating the trigger element 10. In other words, the procedure is started when the controller 8 receives the trigger signal A from the trigger element 10.

[0060] Upon receipt of the trigger signal A, process step 28 is started. In this step, the temperature sensor 24 is read by the controller 8, so that the controller 8 receives a current actual temperature of the lock drive 20 as the device temperature T.

[0061] A table Tab is stored in a data memory of the controller 8, in which temperature values ​​for the device temperature T are assigned to a maximum permissible number M of multiple actuations of the lock drive 20, at which no overheating of the lock drive 20 occurs.

[0062] In this exemplary embodiment, the table Tab, for example, contains four temperature ranges as entries. Up to +40 °C, for example, a maximum number M of 25 consecutive actuations is specified. In a temperature range between +40 °C and +70 °C, the maximum number M is, for example, 15. Between +70 °C and +80 °C, the maximum number M is, for example, 5, with a limit of 3 specified above +80 °C.

[0063] The controller 8 determines the maximum permissible number M for the current device temperature T using the table Tab.

[0064] In a subsequent process step 30, the controller 8 monitors the release element 10 for further subsequent actuations. To this end, the controller 8 monitors whether at least one further actuation of the release element 10 occurs within a specified period, or whether it receives further release signals A within this period. The controller 8 thus counts an actual number N of actuations of the release element 10, or how often the release signal A is received.

[0065] If no further trigger signals A are received, i.e., if the trigger element 10 is only actuated once (actual number N = 1), in a process step 32 the actuation signal B is sent to the lock drive 20 or to the lock motor 22, and thus the locking mechanism is adjusted between the locking position VS and the unlocking position ES.

[0066] In the case of multiple actuations, where the release element 10 is actuated more than once within a specified period, the determined actual number N is compared with the determined maximum number M of permissible actuations in a process step 34.

[0067] As long as the actual number N of the trigger signals A is less than the determined maximum number M, with each trigger signal A in a process step 36 the actuation signal B is sent to the lock drive 20 or to the lock motor 22, and thus the locking mechanism is adjusted several times between the locking position VS and the unlocking position ES.

[0068] If the actual number N reaches or exceeds the maximum number M, actuation of the lock drive 20 is blocked in process step 38. In other words, for trigger signals A exceeding the maximum number M, no further actuation signals B are sent from the controller 8 to the lock drive 20.

[0069] In process step 38, the generation of an actuation signal B is blocked, for example, for a predetermined period of time. Additionally or alternatively, the generation of an actuation signal B is blocked until the device temperature T reaches or falls below a stored threshold value.

[0070] The claimed invention is not limited to the embodiments described above. Rather, other variants of the invention can also be derived by a person skilled in the art within the scope of the disclosed claims without departing from the subject matter of the claimed invention. In particular, all individual features described in connection with the various embodiments can also be combined in other ways within the scope of the disclosed claims without departing from the subject matter of the claimed invention. Reference symbol list 2 Locking device 4 vehicle doors 6 door lock 8 Controller 10 Trigger element 12 Lock mechanisms 14 Locking element 16 Lock 18 gearboxes 20 Lock drive 22 Lock motor 24 Temperature sensor 26th process step 28th process step 30th process step 32nd process step 34th process step 36th process step 38th process step VS locking position ES unlock position A trigger signal B Actuation signal T Device temperature Tab table Maximum number of N Actual number

Claims

[1] Method for operating a locking device (2) for a vehicle door (4), comprising an electric lock drive (20) for actuating a lock mechanism (12), a release element (10) for triggering the lock drive (20), and a temperature sensor (24) for detecting a device temperature (T) of the locking device (2), - wherein, when the release element (10) is actuated, the release element (10) is monitored with regard to further actuations, - wherein, in the case of further actuations of the release element (10), an actual number (N) of actuations is recorded and compared with a maximum number (M) of permissible actuations determined as a function of a recorded device temperature (T), with which the lock drive (20) may be repeatedly triggered, and - wherein a triggering of the lock drive (20) is blocked if the actual number (N) reaches or exceeds the maximum number (M). [2] Method according to claim 1, characterized by , that an electromechanical lock drive (20) is used. [3] Method according to claim 1 or 2, characterized by , that a triggering of the lock drive (20) is blocked for a specified period of time if the actual number (N) reaches or exceeds the maximum number (M). [4] Method according to any one of claims 1 to 3, characterized by , that a triggering of the lock drive (20) is blocked until the device temperature (T) reaches or falls below a stored threshold value when the actual number (N) reaches or exceeds the maximum number (M). [5] Method according to any one of claims 1 to 4, characterized by , that the maximum number (M) is reduced with increasing device temperature (T). [6] Method according to any one of claims 1 to 5, characterized by, that the determination of the maximum number (M) is carried out using a stored table (Tab) in which temperature values ​​for the device temperature (T) are assigned to a respective maximum number (M). [7] Locking device (2) for a vehicle door (4), comprising - a lock mechanism (12) with an electrically coupled lock drive (20) for actuating the lock mechanism (12), - a release element (10) for triggering the lock drive (20), - a temperature sensor (24) for detecting a device temperature (T) of the lock device (2), and - a controller (8) coupled via signal technology to the lock drive (20), the release element (10) and the temperature sensor (24) for carrying out a method according to one of claims 1 to 6. [8] Locking device (2) according to claim 7, characterized by , that the lock drive (20) has an electric motor. [9] Vehicle door (4) for a motor vehicle, comprising a locking device (2) according to claim 8.

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