Electronically controlled door latch

Abstract

The present invention relates to an electronically controlled door latch apparatus for a motor vehicle (2), the apparatus comprising an auxiliary battery (5) configured to provide an auxiliary supply voltage, and an electronically controlled door latch (1) comprising a bank of supercapacitors (3) and an electric motor (4), the bank of supercapacitors (3) being charged by a primary supply voltage received from a primary power source (8) of the motor vehicle (2) during normal operating conditions or by the auxiliary supply voltage and configured to provide a backup supply voltage during backup operating conditions when the primary supply voltage is unavailable, and the electric motor (4) being configured to operate the door latch (1) based on the primary supply voltage or the backup supply voltage.

Description

[Technical Field]

[0001] The present invention relates to an electronically controlled door latch apparatus for a motor vehicle, comprising an electronically controlled door latch comprising a bank of supercapacitors and an electric motor, the supercapacitors configured to be charged by a mains supply voltage received from a mains power source of the motor vehicle during normal operating conditions, and the electric motor configured to actuate the door latch based on the mains supply voltage. The present invention further relates to a method for operating an electronically controlled door latch apparatus for a motor vehicle, the apparatus comprising an electronically controlled door latch comprising a bank of supercapacitors and an electric motor, whereby the supercapacitors are configured to be charged by a mains supply voltage received from a mains power source of the motor vehicle, the method comprising the steps of: actuating the door latch with the electric motor based on the mains supply voltage. [Background technology]

[0002] Some automotive systems require the presence of a backup energy source within the vehicle to provide electrical energy in place of or as a supplement to the vehicle's primary power source in the event of a failure or interruption of that same primary power source. Such a backup power source is kept charged by the vehicle's primary power source during normal operation and is readily available when needed, for example, in the event of a vehicle accident or collision.

[0003] As electronically controlled door latches, often referred to as eLatches, increasingly replace purely mechanical latches, one important safety-related topic is how to release a car door when neither a primary nor a backup power source is available. Furthermore, if a mechanical Bowden cable or lever for an electronically controlled door latch is not available, opening a car door without energy can be very difficult. This can occur after a vehicle collision or damage.

[0004] Additionally, there is growing interest from automakers in long-term parking situations where the electronic control unit directly manages the eLatch's power delivery and puts it to sleep to conserve power. State-of-the-art eLatches contain supercapacitors as storage elements and can achieve a backup range of several days, but are unable to deliver energy for long-term parking situations of a week or more. Summary of the Invention

[0005] It is therefore an object of the present invention to provide an easy, inexpensive, and reliable solution for energizing an electronically controlled door latch during such long-term parking situations.

[0006] The object of the present invention is solved by the features of the independent claims. Preferred embodiments are detailed in the dependent claims.

[0007] The object of the present invention is therefore solved by an electronically controlled door latch device for a motor vehicle, comprising an auxiliary battery configured to provide an auxiliary supply voltage, and an electronically controlled door latch comprising a bank of supercapacitors and an electric motor, the bank of supercapacitors being configured to be charged by a main supply voltage or an auxiliary supply voltage received from a main power supply of the motor vehicle during normal operating conditions and configured to provide a backup supply voltage during backup operating conditions when the main supply voltage is unavailable, the electric motor being configured to operate the electronically controlled door latch based on the main supply voltage or the backup supply voltage.

[0008] Under normal operating conditions, when the vehicle is fully operational, the supercapacitor bank can be charged by a dedicated charger with energy coming from the vehicle's main power supply. During a power loss, such as in the event of an accident, the supercapacitor bank can provide energy to operate an electronically controlled door latch for the first few days. During a long-term power loss, the primary battery provides energy to maintain the operating voltage of the supercapacitor bank, for example, to operate an electronically controlled door latch via an electronic control unit. Operating the electric motor of an electronically controlled door latch typically requires high-current pulses that the auxiliary battery alone cannot provide. Therefore, the energy provided by the supercapacitor bank is needed to drive the electric motor. The energy of the supercapacitor bank is maintained by the auxiliary battery.

[0009] A normal or regular operating condition should be understood as a mode in which the main power supply provides electrical energy to operate the electric motor. A backup operating condition should be understood as a mode in which the main power supply no longer provides electrical energy to operate the electric motor.

[0010] The main power supply is preferably provided as a vehicle battery delivering, for example, 12 or 24 V DC. During normal operating conditions, the main power source charges a bank of supercapacitors that provide a backup supply voltage. In this regard, the vehicle and / or the electronically controlled door latch may be equipped with a charger controllable by an electronic control unit, as described below, and in particular as described below, for recharging the bank of supercapacitors starting from the main supply voltage whenever power from the main supply voltage is available. The electric motor is preferably configured to operate the electronically controlled door latch for locking and unlocking the vehicle doors.

[0011] More generally, the expression "electronically controlled door latch" should be understood as a means for locking a movable element between an open and a closed position, thereby opening and closing access to interior compartments of a motor vehicle, including, for example, the trunk, rear hatch, hood lid or other closed compartment, window regulator, sunroof, as well as the side doors of the motor vehicle. The proposed electronically controlled door latch makes it possible, for example, to comply with security and safety regulations requiring the vehicle doors to remain open even if the vehicle's main power supply fails or if the electrical connection between the main power supply and the vehicle door is interrupted or severed. Such a situation may arise, for example, in the event of an accident or collision involving the vehicle.

[0012] The vehicle may be provided as an electric vehicle. The electronically controlled door latch and / or electronically controlled door latch device may include a housing made of metal, plastic, or a combination thereof. The supercapacitors and / or electric motor are preferably provided within the electronically controlled door latch housing, while the auxiliary battery may be provided inside or outside the housing.

[0013] The electronically controlled door latch may include a four-quadrant controller, which may be applied by a control unit configured with a pulse-width modulated signal for operating the electric motor. Pulse-width modulating the four-quadrant controller preferably means that the four-quadrant controller is switched based on the pulse-width modulated signal. Pulse-width modulation (PWM) or pulse-duration modulation (PDM) is generally understood as a method for reducing the average power carried by an electric signal by effectively dividing the signal into discrete parts. In particular, the electric motor may be operated based on such a PWM signal by turning on a backup supply voltage and / or a primary supply voltage of f. The speed of the electric motor may be controlled by varying the pulse width of the PWM signal.

[0014] A four-quadrant controller can be implemented as an H-bridge and / or with switches implemented as MOSFETs. Generally, an H-bridge is an electronic circuit that switches the polarity of a voltage applied to a load, where the primary and / or backup supply voltage is the voltage and the load is an electric motor. Such an H-bridge allows an electric motor to move forward or backward, for example, to lock or unlock a car door. The name comes from a common circuit diagram representation, where four switches are configured as branches of the letter "H" and the load, i.e., the electric motor, connected as a crossbar. A solid-state H-bridge is typically constructed using reverse-polarity switches, such as PNP bipolar field-effect transistors or p-channel MOSFETs connected to the primary power supply and n-channel MOSFETs connected to ground. Alternatively, p-channel or n-channel MOSFETs can be used on both sides.

[0015] According to a preferred embodiment, the auxiliary battery is provided as a primary battery and / or a non-rechargeable battery. The primary battery is preferably low-leakage and / or non-rechargeable. Advantageously, the auxiliary battery is included in the vehicle maintenance plan for scheduled replacement, for example, every 3-4 years. The auxiliary battery can deliver a voltage of 1.5 or 3V DC and / or can be provided as D cells, C cells, AA cells, AAA cells, PP3 batteries, button cells such as CR2032 or LR44, or a combination or plurality thereof.

[0016] In a further preferred embodiment, the electronically controlled door latch device or electronically controlled door latch comprises a logic element configured to connect the auxiliary battery to the supercapacitor bank a predetermined time after the main supply voltage becomes unavailable. The logic element may be provided as a diode and / or may function in particular to connect the auxiliary battery to the supercapacitor bank to recharge the supercapacitor bank when the voltage across the supercapacitor bank falls below a threshold and when the main power source is no longer available.

[0017] According to another preferred embodiment, the time period is 5, 7 or 10 days. Thus, for example, in long-term parking situations exceeding 5, 7 or 10 days, the auxiliary battery can intelligently provide energy to charge the supercapacitor bank. In another embodiment, the electronically controlled door latch device or electronically controlled door latch comprises a logic element configured to connect the auxiliary battery to the supercapacitor bank when the main supply voltage becomes unavailable and the voltage of the supercapacitor bank falls below a threshold.

[0018] In a further preferred embodiment, the electronically controlled door latch comprises a switch arranged between the auxiliary battery and the bank of supercapacitors, which may be provided as a transistor, for example as a MOSFET, or as any other semiconductor switching element.

[0019] According to another preferred embodiment, the electronically controlled door latch comprises an electronic control unit configured to control the electric motor and operating based on the main supply voltage or the auxiliary supply voltage. The control unit may be provided as a microprocessor, microcontroller, or similar computing module, and is configured to control the operation of the electric motor, particularly via a four-quadrant controller, particularly based on the value of the main voltage and / or the backup supply voltage. Additionally, the control unit may be configured to connect to other controllers of the vehicle, such as, for example, a control device of the vehicle.

[0020] The control unit may be further configured to determine that a crash operating condition has occurred when the value of the main supply voltage falls below a predetermined threshold. In this regard, the electronic control unit may comprise an embedded memory, e.g., a non-volatile random access memory, coupled to the computing module that stores appropriate programs and computer instructions, e.g., in the form of firmware. Alternatively, the control unit may comprise separate component logic circuitry to perform the functions of the computing module and memory.

[0021] In a further preferred embodiment, the door latch is provided Bowden cable-free and / or lever-free. The terms Bowden cable-free and / or lever-free mean that a Bowden cable and a lever are not available, respectively. Thus, when a mechanical Bowden cable or lever is no longer available for an electronically controlled door latch, the proposed solution allows the vehicle door to be opened when the vehicle's main power source is no longer available.

[0022] According to another preferred embodiment, the supercapacitor group comprises at least one first supercapacitor cell, preferably at least one first supercapacitor cell and a second supercapacitor cell, connected together to jointly provide a backup supply voltage. Supercapacitor cells, also known as supercapacitors, supercapacitors, SCs, or ultracapacitors, are high-capacity capacitors that typically have much higher capacitance values ​​but lower voltage limits than other capacitors, bridging the gap between electrolytic capacitors and rechargeable batteries. Supercapacitors typically store 10 to 100 times more energy per unit volume or mass than electrolytic capacitors, can accept and deliver charge much faster than batteries, and can withstand many more charge and discharge cycles than rechargeable batteries.

[0023] When fully charged, the supercapacitor cell includes a voltage of, for example, 2.45 V. Therefore, when the first supercapacitor cell and the second supercapacitor cell are connected to each other, the backup power supply voltage provided jointly is equal to 4.9 V. Preferably, at least two, two, three, or four supercapacitor cells are connected in series to form a supercapacitor group. The vehicle battery preferably includes a voltage of 12 V. The automobile and / or the electronically controlled door latch may include a charging module controllable by the control unit to recharge the supercapacitor group starting from the main supply voltage whenever power from the main supply voltage is available.

[0024] In a further preferred embodiment, the electronically controlled door latch includes an auxiliary battery. In such a case, the auxiliary battery is contained within and / or located within the electronically controlled door latch. Alternatively, the auxiliary battery can be separate from the electronically controlled door latch, e.g., located away from the electronically controlled door latch and / or door.

[0025] This object is further solved by a motor vehicle comprising an electronically controlled door latching device as described above and a charger for the supercapacitor bank, whereby the main power supply is connected to the supercapacitor bank via the charger.

[0026] In this regard, the motor vehicle and / or the electronically controlled door latch may be provided with a charger, particularly controllable by the electronic control unit, for recharging the supercapacitors starting from the mains supply voltage whenever power from the mains supply voltage is available.

[0027] This object is further solved by a method of operating an electronically controlled door latch device for a motor vehicle, comprising an auxiliary battery configured to provide an auxiliary supply voltage, and an electronically controlled door latch comprising a bank of supercapacitors and an electric motor, the bank of supercapacitors being configured to be charged by a main supply voltage received from a main power supply of the motor vehicle or by the auxiliary supply voltage in normal operating conditions, and configured to provide a backup supply voltage in backup operating conditions when the main supply voltage is unavailable, the method comprising the following steps: operating the door latch with the electric motor on the basis of the main supply voltage or the backup supply voltage.

[0028] Further embodiments and advantages of the method can be derived by those skilled in the art from the electronically controlled door latch as described above. [Brief explanation of the drawings]

[0029] [Figure 1] FIG. 1 is a schematic circuit diagram of an electronically controlled door latch device for an automobile equipped with an electronically controlled door latch according to a preferred embodiment.

[0030] Description of the embodiment

[0031] 1 shows a schematic circuit diagram of an electronically controlled door latching arrangement for a purely schematic automobile 2, which includes an electronically controlled door latch 1. The automobile 2 includes side doors, not shown, each equipped with an electronically controlled door latch 1. Additionally, electronically controlled door latches 1 may be associated with the rear hatch, hood lid or other enclosed compartment, window regulators, and sunroof of such automobile 2, in addition to the side doors.

[0032] The electronically controlled door latch 1 includes a housing made of plastic, metal, or a combination thereof. The housing contains a group of supercapacitors 3 and an electric motor 4. An auxiliary battery 5, which is provided as a main battery, is also contained within the housing, and each is a part of the electronically controlled door latch 1. The auxiliary battery 5 may also be located outside the respective outer housing of the electronically controlled door latch 1 within the vehicle 2. The electronically controlled door latch 1 is provided without a Bowden cable and / or a lever.

[0033] The vehicle 2 comprises a mains power supply 6, which may be provided as a standard vehicle battery as known from the prior art, and which delivers a mains supply voltage of 12V DC during normal operating conditions. The mains power supply 6 is connected via a rectifier diode 7 to a charger 8, which is connected to the supercapacitors 3 for charging them.

[0034] Thus, under normal operating conditions, the supercapacitors 3 are charged by the main supply voltage received from the main power supply 6 of the vehicle 2. The auxiliary battery 5 is connected to the supercapacitors 3 via a transistor switch 9, so that the supercapacitors 3 can also be charged by the auxiliary supply voltage received from the auxiliary battery 5.

[0035] For example, when the main supply voltage is unavailable because the vehicle 2 experiences an accident that destroys the electrical connection between the main power source 6 and the electric motor 4, the supercapacitors 3 provide the backup supply voltage so that the electric motor 4 can operate the electronically controlled door latch 1 based on the backup supply voltage instead of the main supply voltage during normal operating conditions.

[0036] The electronically controlled door latch 1 further includes a logic element 10 that operates the switch 9 to connect the auxiliary battery 5 to the supercapacitor bank 3 at a predetermined time after the main supply voltage is unavailable, for example, during a long-term parking situation of 5, 7, or 10 days. The electronically controlled door latch 1 also includes a computerized electronic control unit 12 that controls the electric motor 4 and is operated based on the main or auxiliary supply voltage.

[0037] The supercapacitor group 3 comprises a first supercapacitor cell and a second supercapacitor cell 6 connected in series, with the first supercapacitor cell 6 having its negative terminal connected to ground. When fully charged, each supercapacitor cell delivers, for example, 2.45 V DC, and the supercapacitor group 3 delivers a backup supply voltage of 4.9 V DC. In addition, two or more supercapacitor cells 6 can be connected in series to deliver a higher backup supply voltage.

[0038] While the invention has been illustrated and described in detail in the drawings and the foregoing description, such illustrations and descriptions are to be considered illustrative or exemplary, and not restrictive, and the invention is not limited to the disclosed embodiments. Other variations of the disclosed embodiments will be understood and effected by those skilled in the art in practicing the claimed invention, from a consideration of the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite articles "a" or "an" do not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope. [Explanation of symbols]

[0039] 1...Electronically controlled door latch 2...Automobiles, 3...Supercapacitor group, 4...electric motor, 5...Auxiliary battery, 6...Main power supply, 7...rectifier diode, 8...Charger, 9...switch, 10...Logic element, 11...Supercapacitor cell, 12...control unit, Vbatt: main supply voltage, Vsc...Backup supply voltage.

Claims

1. An electronically controlled door latch device for a motor vehicle (2), comprising: an auxiliary battery (5) configured to provide an auxiliary supply voltage; An electronically controlled door latch (1) comprising a bank of supercapacitors (3) and an electric motor (4); Equipped with the supercapacitors (3) are charged by a main supply voltage received from a main power source (6) of the vehicle (2) during normal operating conditions or by the auxiliary supply voltage; configured to provide a backup supply voltage during a backup operating condition when the primary supply voltage is unavailable; The electric motor (4) is configured to operate the door latch (1) based on the main supply voltage or the backup supply voltage.

2. 2. The electronically controlled door latch device according to claim 1, wherein the auxiliary battery (5) is provided as a primary battery and / or a non-rechargeable battery.

3. 3. The electronically controlled door latch device of claim 1, wherein the electronically controlled door latch (1) comprises a logic element (10) configured to connect the auxiliary battery to the bank of supercapacitors (3) at a predetermined time after the main supply voltage becomes unavailable.

4. 2. The electronically controlled door latch device of claim 1, wherein the time period is 5 days, 7 days, or 10 days.

5. The electronically controlled door latch device according to any one of claims 1 to 4, wherein the electronically controlled door latch (1) comprises a switch (5) arranged between the auxiliary battery (5) and the group of supercapacitors (3).

6. 6. The electronically controlled door latch device according to claim 1, wherein the electronically controlled door latch (1) comprises an electronic control unit (12), the electronic control unit (12) being configured to control the electric motor (4) and being operated based on the main supply voltage or the auxiliary supply voltage.

7. The electronically controlled door latch device according to any one of claims 1 to 6, wherein the door latch (1) is provided in a Bowden cable-free and / or lever-free manner.

8. 8. The electronically controlled door latch device according to claim 1, wherein the supercapacitor group (3) comprises at least a first supercapacitor cell (11), preferably at least a first supercapacitor cell (11) and a second supercapacitor cell (11) connected to each other and jointly providing the backup supply voltage.

9. The electronically controlled door latch device according to any one of claims 1 to 8, wherein the electronically controlled door latch (1) comprises the auxiliary battery (5).

10. A motor vehicle (2) equipped with an electronically controlled door latch device according to any one of claims 1 to 9, The vehicle (2) comprises a charger (8) for the supercapacitor group (3), and the main power source (6) is connected to the supercapacitor group (3) via the charger (8).

11. 1. A method for operating an electronically controlled door latch device of a motor vehicle (2), comprising: The device comprises: an auxiliary battery (5) for providing an auxiliary supply voltage; An electronically controlled door latch (1) comprising a bank of supercapacitors (3) and an electric motor (4); Equipped with the supercapacitors (3) are configured to be charged by a main supply voltage or the auxiliary supply voltage received from a main power source (6) of the vehicle (2) under normal operating conditions, and to provide a backup supply voltage under backup operating conditions when the main supply voltage is unavailable; The method comprises: The method includes the step of actuating the door latch (1) with an electric motor (4) based on the main supply voltage or the backup supply voltage.

Images