DOOR LOCK, ESPECIALLY MOTOR VEHICLE DOOR LOCK

Description

[0001] The invention relates to a door lock, in particular a motor vehicle door lock, with a locking mechanism consisting essentially of a rotary latch and a locking pawl, furthermore with an electromechanical opening drive for the locking mechanism, and with at least one emergency energy source for powering the opening drive in the event of emergency opening of the locking mechanism, wherein the emergency energy source is charged by means of a main energy source according to a control unit.

[0002] For convenience, so-called electric locks are increasingly used in modern vehicle door locks. These locks feature an electric motor that opens the door. A corresponding opening signal for the electric motor is typically generated by a sensor or switch, which can be located, for example, in or on an exterior door handle. Of course, it is also possible to activate such a sensor without a handle. The vehicle door lock can also be opened wirelessly. Such keyless vehicle systems, including an emergency power source, are described, for example, in DE 20 2016 105 621 U1.

[0003] The prior art, as defined by US 10,138,656 B2, involves a control unit that monitors the charge level of the emergency power source and ensures that the emergency power source is recharged using the electrical power supplied by the main power source. In this context, the primary focus is on ensuring reliable operation even in the event of an accident.

[0004] In an electronic lock with a power failure control circuit according to EP 2 659 075 B1, a supercapacitor charger is implemented, which is connected to a microcontroller. During normal operation, the microcontroller ensures that the supercapacitor charger is switched on when the charge level of at least one supercapacitor falls below a desired level. Conversely, the supercapacitor charger is switched off when the charge level of the respective supercapacitor reaches a desired level.

[0005] US Patent 6,914,346 B2 describes a motor vehicle door lock assembly in which the emergency power source is designed as a supercapacitor and mounted on an electronic circuit board. This allows the emergency power source to be integrated into an associated lock housing.

[0006] From DE 10 2014 105874 A1, a method for operating a motor vehicle lock for an adjustable locking element of a motor vehicle is known, wherein the motor vehicle lock is equipped with a lock latch for holding engagement with a locking wedge or the like and a locking pawl associated with the lock latch, wherein an opening auxiliary drive is provided for the motorized lifting of the locking pawl, wherein the motor vehicle lock has an emergency power supply arrangement with at least one rechargeable energy storage device, and wherein the power supply of the motor vehicle lock in an emergency operation generated by a predetermined emergency, in particular in the event of failure of a central battery of the motor vehicle, is at least partially taken over by the rechargeable energy storage device.It is proposed that at least one energy storage device be charged upon detection of an emergency warning signal, with the emergency warning signal indicating that a predetermined emergency is imminent.

[0007] Finally, utility model DE 20 2016 106 542 U1 relates to a supercapacitor charging system. For this purpose, the charging system is equipped with an energy management controller, which is used to charge and discharge at least one supercapacitor. Furthermore, the energy management controller is able to detect and determine the charge level. Depending on this, charging is either continued or stopped.

[0008] The current state of the art has proven effective when it comes to integrating an emergency power source into the door lock's function and using it to manage vehicle situations where the primary power source is unable to supply the electric motor with the necessary electrical energy to open the lock as desired, for example, due to insufficient voltage or an accident. In this context, in addition to conventional rechargeable batteries, so-called supercapacitors are increasingly being used as emergency power sources. These are typically electrochemical capacitors whose advantage lies in the fact that, compared to batteries of the same weight, they have only about 10% of the energy density, while their power density is approximately 10 to 100 times greater.For this reason, supercapacitors can be charged and discharged much faster compared to batteries. They also boast a long lifespan because they are suitable for significantly more switching cycles than batteries of the same capacity.

[0009] Accordingly, supercapacitors can be used as emergency power sources, for example, on circuit boards and inside a lock housing. However, as with any power source, including emergency power sources, supercapacitors face the problem that their electrical power output can decrease due to self-discharge after, for example, a prolonged period of inactivity of the associated vehicle. This can lead to a point where the electric motor for opening the lock is no longer able to open it in an emergency. A similar problem arises if the electrical connection between the emergency power source and the main power source is torn or interrupted, for example, as a result of an accident or crash. The emergency power source is typically recharged when the vehicle is started.This is because then enough electrical energy is available via the generator or, for example, recuperators to complete the charging process.

[0010] However, if an accident or other interruption of the connection between the main power source and the emergency power source occurs immediately after the journey begins, there is a risk that the emergency power source will not have sufficient stored energy at that time to unlock the door in the event of a subsequent emergency opening. Typically, the electric motor-driven opening mechanism disengages a locking pawl from its engagement with the rotary latch, allowing the rotary latch to then open, for example, with spring assistance or due to the force of the door seal, releasing a previously engaged locking bolt. Only then can the corresponding vehicle door be opened. The invention aims to remedy this situation.

[0011] The invention is based on the technical problem of further developing such a door lock, and in particular a motor vehicle door lock, in such a way that emergency opening is possible even immediately after starting the journey.

[0012] To solve this technical problem, a generic door lock and in particular a motor vehicle door lock is characterized within the scope of the invention in that the emergency energy source is charged as soon as the control unit receives an unlocking signal for the lock.

[0013] The invention is based on the premise that the unlocking signal for the locking mechanism is always, or must be, triggered before the starting of a vehicle, for example, by a starting device, provided that a vehicle door and thus the associated vehicle door lock is in a closed state. In the unlocking process and the associated unlocking signal for the locking mechanism, a mechanically operated vehicle door lock, for example, involves closing an actuating lever chain from the exterior door handle to the locking mechanism. Subsequently, manual action on the exterior door handle can release the locking pawl from its engagement with the rotary latch.

[0014] In the present invention, a mechanical actuating lever chain is not typically implemented. Accordingly, the unlocking of the vehicle door lock following the receipt of the unlocking signal corresponds to the activation of a sensor or switch, for example, associated with the exterior door handle, which can then detect actuations of the exterior door handle. Consequently, if the exterior door handle, and thus the sensor or switch, is subsequently actuated, the corresponding follow-up signal is interpreted as an opening signal, so that the electromechanical opening drive is then energized to open the lock normally.

[0015] Only now can the vehicle door be opened, granting access to the interior for a user wishing to enter. The user must then typically activate the starter so that the vehicle starts moving and, in the prior art, the main power source can charge the emergency power source. According to the invention, however, this charging process occurs significantly earlier, namely, it is initiated by the unlock signal for the locking mechanism. Since the control unit dictates, monitors, and controls the charging process of the emergency power source from the main power source, the receipt of the unlock signal by the control unit, according to the invention, immediately ensures that the emergency power source is charged. All of this occurs—as described—before the starter (ignition lock) is activated or engaged.This usually allows the emergency power source to be charged sufficiently within the time between receiving the unlock signal and starting the system using the starting device to enable at least a single opening operation using the electric motor. In other words, the aforementioned timeframe is generally sufficient for the emergency power source to reach a minimum charge level that allows at least the previously described single opening operation to be completed by the electric motor.

[0016] Consequently, the invention is, for the first time, capable of providing emergency opening of the associated vehicle door lock even if an accident occurs immediately during or after starting the vehicle. In other words, an accident directly after starting the journey can be managed in this way because, even in such a case, the emergency power source, due to its minimum charge level, is able to control the electric motor for emergency opening in such a way that the lock is reliably opened. This ultimately eliminates the need for any mechanical redundancies, resulting in significant design and cost advantages.

[0017] In an advantageous embodiment, the unlocking signal is transmitted wirelessly and / or via a wired connection to the control unit. In the case of a wireless unlocking signal, for example, keyless access can be implemented, as described in the previously referenced DE 20 2016 105 621 U1. If, on the other hand, the unlocking signal is transmitted via a wired connection to the control unit, the authorization of the user seeking access is usually queried and verified via an inserted key or an activated sensor. Subsequently, the unlocking signal is generated and transmitted via a wired connection to the control unit, enabling the unit to immediately and subsequently ensure that the emergency power source is charged using the main power source.

[0018] For this purpose, the control unit typically bypasses the previously discussed starting device after receiving the unlock signal and connects the main power source directly to the emergency power source. This means that, unlike prior art, the electrical power supply to the emergency power source does not initially run through the starting device from the main power source and is not dependent on it. Rather, after receiving the unlock signal, the control unit ensures that the main power source is directly connected to the emergency power source for charging. It is irrelevant that the starting device has not yet been activated or powered at this point.

[0019] In a further advantageous embodiment, the emergency power source is supplied with an increased initial current at the start of the charging process. This increased initial current is maintained primarily until the minimum charge level is reached. As previously explained, the minimum charge level of the emergency power source corresponds to the requirement that the opening drive can be actuated at least once using this minimum charge level in order to open the lock.

[0020] Once the minimum charge level is reached, the emergency power source is generally supplied with a reduced normal current. This reduced normal current usually reflects the maximum service life of the emergency power source. That is, the reduced normal current is dimensioned and designed to ensure the emergency power source achieves its maximum service life.

[0021] In this context, the control unit ensures that the charging current and / or charging voltage of the emergency power source are monitored and, typically, the charging current and / or charging voltage are regulated by the control unit. Furthermore, various time-dependent current / voltage profiles can be stored in the control unit. These profiles are selected based on the specific emergency power source, electric opening actuator, and primary power source used. This means that, depending on the electrical energy demand of the electric opening actuator in a given case, the initial current and its time profile are predefined to achieve the necessary minimum charge level.In this context, the type of emergency power source used also plays a role, for example whether a battery, a supercapacitor or several supercapacitors are used and what their characteristics are, i.e. how quickly they can be charged.

[0022] Finally, the invention recommends using one or more supercapacitors as an emergency power source. The supercapacitor or supercapacitors in question can be mounted on a circuit board inside a lock housing. Of course, external mounting outside the lock housing is also possible and is included in the invention.

[0023] The result is a door lock, and in particular a vehicle door lock, that ensures the emergency power source is typically charged sufficiently, or at least has reached the minimum charge level, immediately after the vehicle is started, to allow for emergency unlocking even in the event of an accident immediately after driving. This significantly increases safety and eliminates the need for mechanical redundancies. These are the key advantages.

[0024] The invention will now be explained in more detail with reference to a drawing that shows only one embodiment: Fig. 1 shows an overview of the door lock according to the invention in the form of a motor vehicle door lock and Fig. 2 shows a schematic time-dependent signal of the charging current for the emergency energy source.

[0025] The figures depict a door lock, which in this example is a motor vehicle door lock. Its basic structure consists of a locking mechanism 1, 2, essentially comprising a rotary latch 1 and a locking pawl 2. The locking mechanism 1, 2 interacts with an indicated locking bolt or lock holder 3, which is provided on the motor vehicle side, whereas the locking mechanism 1, 2 is typically located inside a motor vehicle door (not shown in detail).

[0026] The locking mechanism 1, 2 is arranged together with an electromechanical opening drive 4 inside a housing 5. Also located inside the housing 5 are an emergency power source 6 and a control unit 7. The emergency power source 6 can be used to energize the opening drive 4 when the locking mechanism 1, 2 is opened in an emergency. Under normal operating conditions, however, the opening drive 4 is powered by a main power source 8.

[0027] It can be seen that both the emergency power source 6 and the main power source 8 are connected to the control unit 7 on the one hand and the electromechanical opening drive 4 on the other. The same applies to the control unit 7, which in this way controls the electromechanical opening drive 4 both during normal operation and emergency opening.

[0028] Outside the lock housing 5 is the main power source 8, located in a vehicle body (not shown in detail), to which the vehicle door (also not explicitly shown) with the vehicle lock located inside is attached. The vehicle or vehicle body also generally has a starting device 9, which is also connected to the control unit 7.

[0029] This also applies to a sensor 10, which is a switch 10 that detects the actuation of an external door handle 11. When the external door handle 11 is actuated to open the lock 1, 2, the sensor or switch 10 sends a signal to the control unit 7. However, this requires that the control unit 7 first unlocks the vehicle door lock.

[0030] According to the exemplary embodiment, this unlocking is initiated by means of an unlocking signal which the control unit 7 receives wirelessly, as shown in the Fig. 1As indicated, the unlocking signal in this embodiment actually originates from a transmitter / receiver unit 12, which could be a radio remote key, a remote control, etc. Generally, a magnetic card or similar device could also be used here, which, upon approaching a user seeking access, is queried via a question-and-answer dialogue regarding the user's authorization. In any case, in this embodiment, the approach of the authorized user seeking access results in the unlocking signal being transmitted wirelessly or via a wired connection to the control unit 7, as shown. The unlocking signal causes the switch 10 to be "armed" and ready to be queried in order to open the lock 1, 2.

[0031] According to the invention, the design is such that the emergency power source 6 is charged as soon as the control unit 7 receives the unlocking signal for the lock 1, 2. In this exemplary embodiment, and without limitation, the unlocking signal originates from the transmitter / receiver unit 12. Alternatively or additionally, the unlocking signal for the control unit 7 can also be provided by a control device, and in particular a door control device, which is not shown in detail.

[0032] Upon receiving the unlock signal, the control unit 7 bypasses the starting device 9. In this way, the main power source 8 is directly connected to the emergency power source 6. That is, the unlock signal and its reception by the control unit 7 immediately results in the main power source 8 being electrically connected to the emergency power source 6 and immediately charging the emergency power source 6. In contrast, in the prior art, such a charging process only occurs when the starting device 9 is activated. According to the invention, this is not necessary because, upon receiving the unlock signal, the control unit 7 bypasses the starting device 9 and connects the main power source 8 directly to the emergency power source 6.

[0033] Based on the Fig. 2 It is now clear how emergency power source 6 is charged over time. In fact, in the Fig. 2A current or charging current I is plotted against time t. It can be seen that the emergency power source 6 is supplied with an increased initial current at the beginning of the charging process. The increased initial current and the consequently increased charging current I for supplying the emergency power source 6 are maintained until a [missing information] is reached. Fig. 2 The indicated minimum charge level L of the emergency power source 6 has been reached. This minimum charge level L of the emergency power source 6 corresponds to the fact that the emergency power source 6 is charged sufficiently to enable the electromechanical opening drive 4 to open the lock 1, 2 at least once during an emergency opening operation.

[0034] In fact, the minimum charge state L of the emergency power source 6 corresponds to the representation according to the Fig. 2This ensures that the integral of the time-dependent current or charging current I(t) reaches a specific value for a single opening, which depends on the electromechanical opening drive 4. As soon as the emergency power source 6 reaches the minimum charge level L = ∫ 0 t 1 I t dt Once the minimum charge level L has been reached, the emergency power source 6 is supplied with a reduced normal current, as can be seen from the time-dependent current profile I following the hatched section in the Fig. 2 can understand the minimum charge level L shown.

[0035] The reduced normal current observed after reaching the minimum charge level L reflects a maximum service life of the emergency power source 6. In any case, the design is such that the control unit 7 regulates the charging current I according to the diagram below. Fig. 2and / or monitors the charging voltage at the emergency power source 6. According to the invention, monitoring the charging current I or the charging voltage by the control unit 7 means that the charging current I and / or the charging voltage for the emergency power source 6 are controlled and / or regulated by the control unit 7. Furthermore, the design is such that the control unit 7 can process various time-dependent current profiles, as described in the Fig. 2 These are shown and stored. Using these current waveforms or corresponding voltage waveforms, differently configured emergency power sources 6, varying electromechanical opening drives 4, and different configurations of the main power source 8 can be reflected, and the respective current / voltage waveform can be adapted to the specific conditions.

[0036] According to the exemplary embodiment, the emergency power source 6 consists of one or more supercapacitors, which are not only arranged inside the lock housing 5, but are also located on a circuit board (not explicitly shown). The same applies to the control unit 7. Reference symbol list:

[0037] 1, 2 Lock 1 Rotary latch 2 Locking pawl 3 Locking bolt or lock holder 4 Opening drive 5 Lock housing 6 Emergency power source 7 Control unit 8 Main power source 9 Starting device 10 Sensor 11 Exterior door handle 12 Transmit / receive device t Time I Charging current L Minimum charge level

Claims

1. Door latch, in particular a motor vehicle door latch, comprising a locking mechanism (1, 2) consisting substantially of a catch (1) and a pawl (2), the door latch further comprising an electromotive opening drive (4) for the locking mechanism (1, 2), at least one emergency power source (6) for supplying current to the opening drive (4) during the emergency opening of the locking mechanism (1, 2), and at least one control unit (7), the emergency power source (6) being charged in accordance with a control unit (7) of the door latch using a main power source (8), characterized in that the emergency power source (6) is charged as soon as the control unit (7) receives an unlocking signal for the locking mechanism (1, 2).

2. Door latch according to claim 1, characterized in that the unlocking signal is transmitted to the control unit (7) wirelessly and / or by wire.

3. Door latch according to either claim 1 or claim 2, characterized in that the control unit (7) bridges a starting device (9) after receiving the unlocking signal and connects the main power source (8) directly to the emergency power source (6).

4. Door latch according to any of claims 1 to 3, characterized in that the emergency power source (6) is supplied with an increased initial current intensity at the beginning of the charging process.

5. Door latch according to claim 4, characterized in that the increased initial current intensity is maintained until a minimum charge state (L) has been reached.

6. Door latch according to claim 5, characterized in that the emergency power source (6) is supplied with a reduced normal current intensity after the minimum charge state (L) has been reached.

7. Door latch according to either claim 5 or claim 6, characterized in that the reduced normal current intensity reflects a maximum service life of the emergency power source (6).

8. Door latch according to any of claims 1 to 7, characterized in that the control unit (7) monitors, in particular regulates, the charging current intensity and / or charging voltage of the emergency power source (6).

9. Door latch according to any of claims 1 to 8, characterized in that different time-dependent current / voltage curves are stored in the control unit (7) depending on the emergency power source (6), electromotive opening drive (4) and main power source (8) used.

10. Door latch according to any of claims 1 to 9, characterized in that the emergency power source (6) is designed as one or more supercapacitors.