Electronic latch release backup system for a motor vehicle door

Abstract

A latch release backup system for a latch assembly of a motor-vehicle door is provided with a key cylinder configured to receive a vehicle key and which is rotatably mounted to the motor-vehicle door, and a mechanical coupling arrangement mounted within the motor-vehicle door and operable to convert a rotation of the key cylinder into actuation of an actuation group of the latch assembly for causing latch release. The key cylinder defines an electrical interface socket designed to receive the vehicle key. An electronic control unit is mounted within the motor-vehicle door and is electrically connected to the electrical interface socket to receive identification information (Id) from the vehicle key when plugged into the electrical interface socket. The mechanical coupling arrangement is normally disengaged from the actuation group of the latch assembly, and the electronic control unit is configured to control selective engagement of the mechanical coupling arrangement to the actuation group of the latch assembly based on the identification information (Id) received from the vehicle key.

Claims

1. A latch release backup system for a latch assembly of a motor-vehicle door, comprising: a key cylinder configured to receive a vehicle key and which is rotatably mounted to the motor-vehicle door, wherein the key cylinder defines an electrical interface socket configured to receive the vehicle key; a mechanical coupling arrangement mounted within the motor-vehicle door and operable to convert a rotation of the key cylinder into actuation of an actuation group of the latch assembly for causing latch release; and an electronic control unit mounted within the motor-vehicle door and electrically connected to the electrical interface socket to receive identification information (Id) from the vehicle key when plugged into the electrical interface socket; wherein the mechanical coupling arrangement is disengaged from the actuation group of the latch assembly, and wherein the electronic control unit is configured to control engagement of the mechanical coupling arrangement to the actuation group of the latch assembly based on the identification information (Id) received from the vehicle key.

2. The system according to claim 1, further comprising a coupling device controlled by the control unit to cause engagement of the mechanical coupling arrangement to the actuation group of the latch assembly.

3. The system according to claim 2, wherein the coupling device is arranged within a case of the latch assembly.

4. The system according to claim 2, wherein the control unit includes a processing module, configured to receive and process the identification information (Id), and to generate a control signal (S.sub.c) to drive the coupling device as a function of the processing.

5. The system according claim 4, wherein the electronic control unit is further configured to receive a power supply signal (V.sub.s) from the electrical interface socket for driving the coupling device.

6. The system according to claim 5, wherein the vehicle key includes a power supply module configured to generate the power supply signal (V.sub.s), and includes a body which carries an electrical interface plug designed to engage the electrical interface socket.

7. The system according to claim 2, wherein the key cylinder includes a main body having a longitudinal axis (A) and defining the electrical interface socket, wherein the mechanical coupling arrangement includes: a rotating arm coupled to the main body and designed to rotate upon rotation of the key cylinder about the longitudinal axis (A); an actuator carrying an external lever that is rotatably mounted to a case of the latch assembly outside of the case; and a coupling element connecting the rotating arm to the external lever so that rotation of the rotating arm causes a corresponding rotation of the external lever, wherein the coupling device is housed within the case and is configured to selectively couple the external lever to the actuation group of the latch assembly.

8. The system according to claim 7, wherein the coupling device includes a coupling body, mechanically coupled to the actuation group, and an electrically controlled element operable by the control unit to selectively cause engagement of the coupling body with the external lever so that the coupling body rotates with the external lever.

9. The system according to claim 8, wherein the electrically controlled element includes a solenoid, and a magnet element integral with the coupling body and operatively coupled to the solenoid.

10. The system according to claim 8, wherein the coupling device includes an internal lever integral to the coupling body and which is mechanically coupled to the actuation group.

11. The system according to claim 1, wherein the electrical interface socket is a USB interface.

12. The system according to claim 1, wherein the electronic control unit is arranged within a case of the latch assembly.

13. The system according to claim 1, wherein the key cylinder and the vehicle key do not have any matching mechanical code.

14. A door latch system for a motor vehicle door, comprising: a latch assembly having a latch mechanism operable in a latched mode to hold the motor vehicle door in a closed state and in an unlatched mode to release the motor vehicle door in an opened state; a latch release mechanism for shifting the latch mechanism from the latched mode into the unlatched mode; and a latch release backup system having a key cylinder rotatably mounted to the motor vehicle door and having an electrical interface socket configured to receive an electric interface plug of a vehicle key, a mechanical coupling arrangement operable to convert rotation of the key cylinder into rotation of an actuator element, an actuator unit operable in a disconnected mode to disconnect the actuator element from the latch release mechanism and in a connected mode to connect the actuator element to the latch release mechanism, and an electronic controller electrically connected to the electric interface socket to receive identification information (Id) from the vehicle key when plugged into the electrical interface socket and control actuation of the actuator unit for shifting the actuator unit from its disconnected mode into its connected mode upon authentication of the identification information (Id) received from the vehicle key.

15. The door latch system according to claim 14, wherein said actuator unit includes a lever configured to engage the latch release mechanism, and a power-operated device configured to move the lever between a first position disengaged from connection with the actuator element and a second position engaged with the actuator element.

Description

DRAWINGS

(1) A preferred, non-limiting embodiment of certain aspects of the present invention will be described by way of example with reference to the accompanying drawings, in which:

(2) FIG. 1 is a schematic representation of a motor vehicle equipped with a conventional door latch system;

(3) FIGS. 2a-2c show schematic representations of a vehicle door with a latch release backup system and an electronic key and key cylinder arrangement which are collectively constructed according to aspects of the present disclosure;

(4) FIG. 3 is a schematic representation of a latch assembly associated with the latch release backup system of the present disclosure;

(5) FIG. 4 is a general block diagram of the electronic key and a control unit associated with the latch assembly associated with the latch release backup system of the present disclosure; and

(6) FIGS. 5a-5b show an embodiment of a coupling mechanism associated with the latch release backup system of the present disclosure in two different operating conditions.

(7) Corresponding reference numerals indicate corresponding components throughout the several views of the drawings.

DETAILED DESCRIPTION

(8) Example embodiments will now be described more fully with references to the accompanying drawings. The example embodiments are provided so that this disclosure will be thorough, and will fully convey the scope to those who are skilled in the art. Numerous specific details are set forth such as examples of specific components, devices, and methods, to provide a thorough understanding of embodiments of the present disclosure. It will be apparent to those skilled in the art that specific details need not be employed, that example embodiments may be embodied in many different forms and that neither should be construed to limit the scope of the disclosure. In some example embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail.

(9) FIGS. 2a-2c schematically show a motor-vehicle door 18 provided with a latch release (or unlock) backup system 20 according to the present disclosure and including a key cylinder 21 and a latch assembly 22 operatively coupled thereto. It will be understood that operation of latch assembly 22 will be herein discussed only in relation to key cylinder 21 and the latch release backup functions. Accordingly, other aspects and functions of the latch assembly 22 which may not differ from known solutions (i.e. such as discussed with reference to FIG. 1) are not discussed in detail herein.

(10) According to an aspect of the present disclosure, key cylinder 21 is electronic (and is thus denoted hereinafter as electronic key cylinder 21) in that it no longer has any mechanical code or mechanical antitheft feature. Electronic key cylinder 21 includes a cylindrical main body 23, e.g. made of plastic material, which is mounted to vehicle door 18 for rotation relative to a rotary axis A. Main body 23 of electronic key cylinder 21 defines an electrical interface socket or receptacle 24 configured for electrical connection to a vehicle key 25. Vehicle key 25 is also electronic since it no longer has any mechanical code or mechanical antitheft feature. Thus, the combination of electronic key cylinder 21 and electronic vehicle key 25 defines an electronic key and key cylinder arrangement.

(11) Main body 23 defines both the electrical interface and a related case, mechanically matching the same electrical interface. To this end, electrical interface socket 24 is designed to implement any suitable electrical interface, preferably a standard electrical interface such as the USB (Universal Serial Bus) interface (either in the standard, mini or micro version), as illustrated in the example shown in FIG. 2b. However, it is understood that other types of electrical interfaces, either standard (e.g. a standard low voltage DC power supply plug or socket, a PS/2 interface or a HDMI interface) or application-specific, are within the intended scope of the present disclosure.

(12) Moreover, electrical interface socket 24 may have a standard pinout or a specific, proprietary, pinout. According to one non-limiting embodiment, electrical interface socket 24 includes a power supply pin 24a designed to receive a power supply signal V.sub.s, a ground reference pin 24b designed to be coupled to a reference voltage GND (e.g. a ground reference), and a data pin 24c designed to receive a data signal S.sub.d. In another non-limiting solution, just two pins may be used if the power supply is also used to transmit the coded data signal S.sub.d in a manner similar to a power-line.

(13) Electronic vehicle key 25 is designed to plug into electrical interface socket 24 and to electrically interface therewith. Vehicle key 25 includes a respective main body 25 having a circular or elliptical cross section, as shown in FIG. 2c, which carries an electrical interface plug 27 that is configured to engage electrical interface socket 24. Electrical interface plug 27 implements the same standard electrical interface as the electrical interface socket 24, in the particular example, the USB standard electrical interface. Moreover, electrical interface plug 27 has a corresponding pinout and therefore includes (not shown in detail in FIG. 2c) a respective power supply pin, a ground reference pin, and a data pin. Again, only two pins may be used in another possible embodiment.

(14) As is also schematically shown in FIG. 4, vehicle key 25 includes a case which houses a power supply module 28 (e.g. a battery) and an output interface module 29 that is coupled to a memory 29 (e.g. a non-volatile memory). In a possible embodiment, memory 29 stores a key identification and authorization code Id (or, in general, any identification information associated thereto and/or indicative of the same code), and output interface module is operable to transmit, through the data pin of electrical interface plug 27, the identification and authorization code Id to electronic key cylinder 21 (or any information associated thereto). Such transmission may be initiated by a user (e.g. pressing a button on the case 25) or may be started automatically when electronic vehicle key 25 is inserted into electronic key cylinder 21. Output interface module 29 is further operable to provide power supply to electronic key cylinder 21 and, in particular, the power supply signal V.sub.s and the reference voltage GND.

(15) Electronic key cylinder 21 further includes (FIGS. 2a and 2b) a movable arm 26 that is fixed to or integrally formed with main body 23 for common rotation around the longitudinal axis A of cylindrical main body 23. Movable arm 26 carries, at an end portion 26a thereof and at a set distance from the longitudinal axis A, a first end of a connecting element 28 which in this non-limiting example can be in the form of a Bowden cable or a rod. A second end of connecting element 28 is mechanically coupled to a moveable actuator element, preferably positioned outside of latch assembly 22 (as will be detailed in the following). As such, the moveable actuator element is coupled for common movement with moveable arm 26 of electronic key cylinder 21.

(16) As will also be discussed in detail in the following, a mechanical connection between the moveable actuator element (coupled to moveable arm 26 of electronic key cylinder 21) and a moveable latch release element of the latch mechanism within latch assembly 22 (i.e. a release lever acting on pawl 8), is normally disengaged but can selectively and temporarily engage in response to actuation of a power-operated actuation unit. In particular, this mechanical connection is normally operable in a disengaged or first operating condition to define a disconnected mode such that movement of the actuator element caused by rotation of electronic key cylinder 21 and movable arm 26 does not cause any action within latch assembly 22, namely such movement of the actuator element does not result in the release or unlocking of the latch mechanism. In a possible embodiment, rotation of electronic key cylinder 21 may be a free 360 rotation around its longitudinal axis A caused by a corresponding rotation of any suitable element inserted into electronic key cylinder 21 and having the proper electrical interface.

(17) In contrast, once the mechanical connection is shifted into an engaged or second operating condition defining a connected mode, movable arm 26 and the actuator element are mechanically connected to the release mechanism or to the unlocking chain of the latch mechanism (e.g. to the release lever within latch assembly 22) such that rotation of electronic key cylinder 21 (caused by a corresponding rotation of vehicle key 25 inserted within the same electronic key cylinder 21) causes unlocking or release of the latch mechanism and allows opening of vehicle door 18 (for example, rotation of movable arm 26 is translated into a rotation of the release lever within latch assembly 22).

(18) In the discussed embodiment, the mechanical connection between movable arm 26 of electronic key cylinder 21 and the moveable actuator element of latch assembly 22 is always maintained, both in the first and in the second operating conditions.

(19) Electronic key cylinder 21 is also electrically connected to latch assembly 22 in order to communicate the identification and authorization code Id received from vehicle key 25 (or any information associated thereto and/or indicative of the same code) and also to provide the power supply. An electrical cable 30, carrying the above power supply signal V.sub.s, ground reference GND and data signal S.sub.d, connects electronic key cylinder 21 to latch assembly 22. As previously discussed, electrical cable 30 could optionally provide only the power supply signal V.sub.s and not the data signal S.sub.d, in case the same power supply signal V.sub.s where used to transmit the code or the information associated thereto.

(20) In particular, engagement of the above mechanical connection between movable arm 26 of electronic key cylinder and the release element of the latch mechanism is based on processing of the identification and authorization code Id received from vehicle key 25 (or of any information associated thereto).

(21) In more details, as schematically shown in FIG. 3 and according to an aspect of the present solution, latch assembly 22 includes a case 31 which carries on an external surface thereof an electrical connector 32 configured for connection to electrical cable 30 so as to receive the power supply signal V.sub.s, ground reference GND and data signal S.sub.d from electronic key cylinder 21 (or just the power supply signal V.sub.s, and possibly the ground reference GND, in a different embodiment).

(22) In a manner not shown in detail, case 31 internally houses actuation group 6 of latch assembly 22 and, in particular, the ratchet and pawl of the latch mechanism (as previously discussed in more details with reference to FIG. 1). Actuation group is schematically shown and again denoted with reference numeral 6.

(23) Latch assembly 22 further includes a control unit 33 which, in this non-limiting embodiment, is housed within case 31 and is coupled to electrical connector 32. Control unit 33 may also have other functions within latch assembly 22. As schematically shown in FIG. 4, control unit 33 may include an input interface 34 electrically coupled to electrical connector 32 and electrical cable 30, a processing module 35 electrically coupled to input interface 34, and an output interface 36 electrically coupled to processing module 35 and configured to generate and provide at its output an actuation control signal S.sub.c. In particular, input interface 34, processing module 35 and output interface 36 are electrically powered by the power supply signal V.sub.s received from electronic key cylinder 21.

(24) Processing module 35 of control unit 33 includes a microprocessor, a microcontroller or any other suitable processing module, and a non volatile memory storing a firmware including instructions to be performed by control unit 33. Processing module 35 is configured to process the received identification and authorization code Id (or any information associated thereto and/or indicative of the same code) by comparing it to a code stored in the associated memory (or to any information related to the same code), in order to recognize and authorize vehicle key introduced within electronic key cylinder 21. In particular, it is understood that any other known technique for code recognition, e.g. those commonly used for vehicle keys, may be used for the above authentication process; for example any processing technique to evaluate matching of the codes or correspondence of information associated thereto, for example via a function or other features known to control unit 33. In a possible embodiment, communication between vehicle key 25 and control unit 33 may also be of a bi-directional type.

(25) As shown in FIG. 3, latch assembly 22 further includes a power-operated actuation unit 38 having a main body 39 pivotably mounted to case 31. As will be detailed, a segment of main body 39 acts as the moveable actuator element to which the second end of connecting element 28 is secured. In particular, and as better shown in FIGS. 5a and 5b, main body 39 has a first body portion 39a arranged outside of case 31, and a second body portion 39b arranged within the same case 31 (and therefore not accessible from outside of case 31). Main body 39 is, in this non-limiting embodiment, rotatably mounted to case 31 so as to rotate around a longitudinal axis B. First body portion 39a of main body 39 of actuator unit 38 moreover carries, integral thereto, the actuator element, hereinafter referred to as an external lever 40, which extends transverse to the longitudinal axis B. A distal end of lever 40, set at a distance from the longitudinal axis B, is coupled to the second end of connecting element 28.

(26) Accordingly, concurrent rotation of electronic key cylinder 21 (e.g. counter clock-wise) and movable arm 26 causes a corresponding rotation (e.g. also counter clock-wise) of external lever 40 outside of case 31 of latch assembly 22 (this mechanical coupling being present in both the engaged and the disengaged operating conditions).

(27) In particular, when actuator unit 38 is operating in the disconnected mode, rotation of external lever 40 is normally in a free-wheeling or disengaged condition such that it is not coupled to the actuation group 6 and does not cause any action within latch assembly 22. Once actuation unit 38 is shifted into the connected mode, however, external lever 40 is coupled to the actuation group 6 and its rotation causes unlocking or release of the latch (e.g. rotation of external lever 40 in the engaged condition directly or indirectly causes pawl 8 to disengage ratchet 7 within actuation group 6).

(28) In more details and with particular reference to FIGS. 5a and 5b, actuation unit 38 further includes a coupling device 42 that is housed within case 31 (here not shown) and operable, in particular under control of the actuation control signal S.sub.c generated by control unit 33, to cause engagement between external lever 40 and the actuation group 6 of the latching mechanism.

(29) In a possible embodiment, shown in the FIGS. 5a and 5b, coupling device 42 includes a solenoid 44 which receives and is excited by the actuation control signal S.sub.c, and a magnetic element 45 coupled to solenoid 44 and which moves, due to the generated magnetic field, along a direction parallel to the longitudinal axis B.

(30) A coupling body 46 is integrally coupled to magnetic element 45 and carries, at a top surface thereof (with respect to the same longitudinal axis B) and facing second body portion 39b of main body 39 of actuator 38, a lug element 47. In addition, an internal lever 46 is integrally coupled to coupling body 46.

(31) As shown in FIG. 5a, in the first (or disengaged) operating condition, when no magnetic field (no actuation control signal S.sub.c) is generated by solenoid 44, magnetic element 45 and coupling body 46 are arranged at a distance from second body portion 39b of main body 39 of actuation unit 38. In this first operating condition, lug element 47 on coupling body 46 is displaced from engagement with a protruding drive element 50b extending from second body portion 39b of main body 39. As such, rotation of external lever 40 does not cause corresponding rotation of internal lever 46.

(32) As shown in FIG. 5b, in the second (or engaged) operating condition, when the actuation control signal S.sub.c drives solenoid 44, magnetic element 45 moves due to the generated magnetic field and carries, along its movement, coupling body 46 towards second body portion 39b. Accordingly, lug element 47 of coupling body 46 abuts against protruding drive element 50b on second body portion 39b of main body 39 of actuator 38. Moreover, a protruding hub portion 46 of coupling body 46 enters into a seat 50a provided within second body portion 39b.

(33) In this second operating condition, coupling body 46 is therefore mechanically coupled to main body 39 of actuator unit 38, whereby rotation of external lever 40 caused by its connection to arm segment 26 via connecting element 28 is therefore transmitted to coupling body 46. The consequent rotation of coupling body 46 is then transmitted to internal lever 46 and, thereby, to actuation group 6 of latch assembly 22 for causing release or unlocking thereof (any suitable mechanical coupling may be envisaged for the purpose, as will be clear for a person skilled in the field, between internal lever 46 and actuation group 6).

(34) Coupling device 42 moreover includes an elastic element, such as a spring 52, operatively coupled to coupling body 46 and acting as a mechanical return element, as schematically shown in FIGS. 5a-5b.

(35) It is understood that other solutions may be envisaged to selectively cause the releasable mechanical interconnection between actuation group 6 of latch assembly 22 and external lever 40. These alternatives may include, without limitations, arrangements using a micro-motor, or any other low power actuator driven by the control signal S.sub.c generated by control unit 33, and therefore exploiting the energy coming from vehicle key 25 (again, as will be clear for a person skilled in the field).

(36) Engagement between actuator 38 and actuation group 6 in latch assembly 22 is temporary (has a limited duration), suitable for release or unlocking of the latch. Afterwards, the latch can be reset or re-locked mechanically by any conventional means. For example, electronic key 25 being taken out from electrical interface socket (or receptacle) 24 causes interruption of the electrical power supply, and elastic element 52 may return the system in the disengaged state.

(37) The advantages of the discussed solution are clear from the foregoing description.

(38) In any case, it is underlined that latch release backup system 20 of the present disclosure provides the required release/unlocking functions for the user of the vehicle, while allowing elimination of the conventional mechanical key cylinder and latch release mechanical system.

(39) The proposed electronic key and key cylinder arrangement not only allows simplification of the system and reduction of the weight, size and costs, but it also improves security and anti-theft features of the latch system, since the mechanical mechanisms for the release of the latch are not easily accessible, e.g. being arranged within vehicle door 18 and particularly within case 31 of latch assembly 22.

(40) Moreover, the use of an electronic key cylinder allows standardization between vehicles and manufacturers, and in general provides a simplification in the management of vehicle access (e.g. in a vehicle fleet); in particular, programming of vehicle key 25 may require only storing a proper identification code (or information associated thereto) in memory 29, to allow electronic identification and authentication of the key and consequent release of the latch.

(41) Clearly, changes may be made to what is described and illustrated herein without, however, departing from the scope defined in the accompanying claims. For example, it is underlined that control unit 33 of latch release backup system 20 may also be arranged within vehicle door 18, outside case 31 of latch assembly 22, particularly in case of an implementation with conventional mechanical latches.

(42) Moreover, coupling device 42 could be arranged outside of case 31, possibly providing a selective engagement between external lever 40 of the actuator 28 and arm 26 of electronic key cylinder 21 (a fixed mechanical connection being in this case present within the latch between the same actuator 38 and actuation group 6). Also in this case, engagement of the mechanical connection between movable arm 26 of electronic key cylinder 21 and the release of the latch is based on the processing of the identification and authorization code Id received from vehicle key 25 (or of any information associated thereto) by the electronic control unit 33. Moreover, the disclosed latch release backup system 20 may be used also in traditional latch assemblies, envisaging a purely mechanical release, or unlock, action on the latch. In particular, the proposed solution may also advantageously be used to upgrade any existing traditional latch assembly.

(43) The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.