Patent Publication Number: US-7224259-B2

Title: Unlocking system for automobile vehicle doors and the like

Description:
REFERENCE TO RELATED APPLICATIONS 
   This present invention claims priority to French Patent Application No. 02 01 698, filed Feb. 12, 2002. 
   Technical Field 
   The present invention relates to automobile vehicle locks, and more specifically to electrically-powered automobile vehicle locks. 
   BACKGROUND OF THE INVENTION 
   Vehicle locks are used to keep an automobile vehicle door in the closed position. For purposes of this application, the word “door” should be interpreted to extend to any vehicle closure, such as a door, a trunk, a lift gate, etc. The locks allow the door to be opened by operating an internal or external manipulator, such as a key, linked to the lock and operable by a user. Typically, the locks are mounted in the vehicle door and include a claw mechanism designed to release or engage a cooperating means with respect to the lock to unlock and lock the door, respectively. The claw mechanism is urged into its closing position by the cooperating means when the door is closed. A pawl prevents the claw from returning to its release position and keeps the lock in the closed position if the lock is not subject to any release action by, for example, a release control. A vehicle will have both internal and external release controls, such as actuatable door handles. 
   The lock includes an internal or external release lever to connect the lock to a corresponding internal or external release control. Locking the lock prevents the lock from being opened through actuation of the external release control, while unlocking the lock allows the lock to be opened when the external release control is actuated. In the case of an automobile vehicle door, these operations are conventionally performed using a fascia pull or electromechanical actuator. For mechanical locking, generally, it is necessary to provide a linkage between the lock and a key cylinder. 
   Using a key cylinder raises several following problems, however. A key cylinder represents a considerable architectural constraint: the introduction of an object into the window seal can allow a thief to act on the lock-key cylinder linkage to break into the vehicle. This problem may be resolved by bringing the key cylinder and lock closer together, but this solution imposes a constraint on the relative position of the key cylinder and the lock. The problem may also be resolved by providing a linkage between the key cylinder and the lock that resists manipulation through the window seal, but this constrains the linkage movement. The position of the key cylinder is also constrained by the need to ensure that the key cylinder does not block the path of the window glass when it is lowered into the door. 
   The presence of a key cylinder also creates a mechanical constraint. One way of breaking into a vehicle involves tearing the key cylinder from the vehicle door. This is sometimes solved by strengthening the sheet-metal of the door around the lock area, but this adds weight and bulk to the vehicle door. In all of the cases described above, the keys employed in vehicle locks can be easily copied, further adding potential security problems. 
   Electronic remote controls are known ways to lock and unlock vehicle doors. 
   Remote controls are usually battery-powered and operate at high frequencies, such as 315, 433 or 865 MHz. Remote opening systems can operate over ranges on the order of 10 m and are usually supplemented by conventional locks to ensure that locking is always possible even if the remote control or its receiver should fail. 
   One vehicle, the Peugeot 406, has a key that includes a transponder (a passive circuit) that is remotely powered and can be remotely interrogated. The circuit that powers and interrogates the transponder is disposed in the vehicle and prevents the vehicle from starting if the transponder is not responding. In this application, the power feed and disabling circuit is designed to interrogate the transponder when the key is close to the vehicle steering wheel. The circuit operates at frequencies around 125 kHz, i.e., low frequencies, with a range on the order of 5 cm. 
   French patent 2,740,501 discloses a hands-free system for unlocking and/or opening an automobile vehicle trunk. One or two antennae are provided on the vehicle. Presenting a transponder to the antenna or antennae in a predetermined sequence causes unlocking and/or opening of the trunk. The system disclosed in this patent requires powering by the vehicle battery to achieve unlocking and opening and consequently requires the vehicle to be provided with a cylinder lock as a backup should the hands-free system fail. 
   U.S. Pat. No. 5,134,392 discloses a keyless opening system. The opening system employs a transmitter powered by a long-life battery. 
   There is considerable resistance in the art against eliminating the mechanical key cylinder, which makes opening the vehicle possible even if the radio control should fail. 
   European Patent Application 0,694,644 discloses an electrically-released automobile vehicle lock. Lock opening is provided electrically by operating an actuator powered by the vehicle battery. A standby power source, such as a standby battery, is built into the door associated with the lock. If the electrical power supply from the vehicle battery fails, the lock can still be opened using electrical power supplied by the standby battery. This document says nothing about employing a key cylinder in its system. 
   This proposed solution poses a problem with the proper dimensions of the lock opening because the motor should allow the lock to be released under both normal conditions and degraded (e.g., post-impact) conditions. The motor and its speed reduction gear are therefore designed to allow opening under degraded conditions, leading to both electrical and mechanical over-dimensioning with respect to requirements under normal conditions. Motor dimensioning consequently presents a problem for standby powering because motor should be supplied with the energy needed for release under heavy loads, but this amount of energy is excessive and wasteful for normal operating conditions. 
   U.S. Pat. No. 5,552,641 and European Patent Application 1,052,353 disclose locking systems for automobile vehicles based on portable transponders. These documents do not discuss what type of lock is employed in the vehicle. International Application WO-A-0123695 discloses a transmitter for operating a vehicle locking system. Contacts are provided on the transmitter as a way of overcoming failure of the transmitter or vehicle battery. 
   Other documents disclose locks with electrical or mechanical releases, including European Patent Application 0,589,158, European Patent Application 0,828,049, German Patent Application 196 00 524 and International Application WO-A-01/66889. 
   There is consequently a need for an automobile vehicle unlocking system that overcomes the disadvantages of purely mechanical locking systems and avoids the architectural and mechanical constraints caused by mechanical systems. 
   SUMMARY OF THE INVENTION 
   The present invention is a system for unlocking a key cylinderless automobile vehicle door or other vehicle closure. The system comprises an electric lock with mechanical release means able to be enabled and disabled, a portable object having an identifier, a circuit for interrogating the object, adapted to power the object and interrogate the object when it is outside the vehicle, and adapted to supply a signal to the lock authorizing the vehicle door to be unlocked as a function of said identifier. 
   The signal supplied under normal conditions can be a software unlocking signal for electrical release of the lock. The signal supplied under conditions where the vehicle power supply has failed is preferably a signal for enabling mechanical opening of the lock. 
   The interrogating circuit preferably powers the portable object remotely upon interrogation. The portable object can have contacts and the interrogating circuit can have corresponding contacts adapted to be coupled to the contacts of the portable object. 
   The system can have a standby power supply separate from the main power supply of the vehicle, and the interrogating circuit can be powered by the standby power supply. 
   The system preferably comprises an unlocking mechanism receiving an unlocking signal originating from the interrogation circuit. The unlocking mechanism can be linked to the standby power supply. 
   The system preferably comprises standby electronic circuitry powered by the standby power supply and adapted to enable mechanical release of the lock. The standby electronic circuitry can have a low-power mode that terminates upon reception of a signal from a sensor detecting operation of an inner lock release control or an external lock release control. 
   The system can further comprise an electrically releasable lock with a mechanical release that can be enabled by the action of the unlocking mechanism. 
   Other characteristics and advantages of the invention will become more clear from the description that follows given by way of example and with reference to the attached drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a block diagram of the various parts of the system according to one embodiment of the invention; 
       FIG. 2  is a diagrammatic view of a lock that can be used in the inventive system, where the lock is in a closed position and mechanical release is not enabled; 
     FIG  3  shows the lock of  FIG. 2  in an electrical release position; 
       FIG. 4  shows the lock of  FIG. 2  in a closed, unlocked position, allowing mechanical opening; 
       FIG. 5  shows the same lock in a mechanical release position after release of the lock shown in  FIG. 4 ; 
       FIG. 6  is a diagrammatic view of another lock that can be used in the system of  FIG. 1  in a closed position, where the emergency mechanical release is not enabled. 
   

   DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
   The invention involves the use of a portable object that is powered upon interrogation for releasing a lock of an automobile vehicle door or a similar structure. The portable object is interrogated by an interrogating circuit that is typically mounted in the vehicle door. The interrogating circuit can interrogate the object while the portable object is outside the vehicle and additionally furnish electrical power to the portable object. If the results of the interrogation indicate that the portable object is authorized to release the vehicle lock, the circuit supplies the lock on the door with a signal authorizing release of the lock. 
   The use of such a portable object and an associated interrogating circuit for commanding release of a lock avoids requiring a key cylinder in a vehicle door, thereby avoiding the architectural and mechanical constraints caused by key cylinders. 
   The lock is an electric lock with a mechanical release that can be enabled with the electric lock. Under normal operating conditions, when the vehicle battery is supplying sufficient power, the lock can be used purely as an electric lock. However, in the case of power failure, the mechanical release can be enabled using reduced power. This reduces the electric power needed to overcome the failure. 
   The system of the invention overcomes possible failure of the portable object&#39;s power supply because the interrogating circuit is adapted to power the object when the object is outside the vehicle. The system of the invention also resists failure of the vehicle power supply because of its ability to enable mechanical release of the electric lock. A low-power source in the door is sufficient to allow enabling of the mechanical release. Alternatively, mechanical release can be enabled permanently in the system, as explained with reference to  FIG. 6 . 
     FIG. 1  is a block diagram of the various elements of a system according to one embodiment of the invention. A portable object  2  is powered upon interrogation by an interrogating circuit  10  and is thus able to respond to interrogation from the interrogating circuit  10 . As a result, the object  2  can respond to interrogation from the interrogating circuit  10  that is powering the object  2  without requiring the object  2  to have its own separate power supply. Powering of the portable object  2  can be done remotely, i.e. without contact. One solution is to employ a transponder having a coil  4  that powers the object  2  via a magnetic field and that transmits a response to the interrogating circuit  10 .  FIG. 1  shows a transponder with a coil  4  for a circuit  6  powered by the coil  4  and adapted to short-circuit the coil  4  for transmitting a response. The transponder can be remotely powered and interrogated at low frequencies (e.g., at a frequency of 125 kHz). 
   The portable object  2  can also be powered by contact between corresponding contacts  11 ,  13  on the object  2  and the interrogating circuit  10 , respectively. In this case, interrogation can now be advantageously achieved by modulating the power supply voltage, which can limit the number of contacts. The object  2  could therefore be in the form of a card that is introduced into a slot located, for example, between a vehicle door and the door frame to provide contact between the contacts  11 ,  13 . This card reading position would allow the power supply and/or interrogation contacts of the card to be protected. 
   The portable object  2  has a ROM  8  or other memory, which is reprogrammable and particularly designed to store an identifier even when the object  2  is not powered. The identifier uniquely characterizes the object  2 . The use of such an identifier stored in the memory  8  provides more possible combinations than the possible mechanical combinations of a physical key, enhancing security. Thus, for example, an identifier stored on 15 bits will provide more than 60,000 combinations, while the number of possible combinations for a mechanical key is on the order of 3000 combinations. 
   The memory  8  is connected to circuit  6  to allow transmission of the identifier from the portable object to the interrogating circuit when the circuit  6  is interrogated. From this point of view, any known suitable interrogation protocol (e.g., rotating codes) can be used to provide encryption of the transmitted data. For example, arrangements can be made for temporarily or definitively blocking a vehicle door upon receiving N incorrect codes. 
   Note that  FIG. 1  is a representative view for illustrative purposes only; thus, the distinction between circuit  6  and memory  8  in the portable object  2  has only been provided for clarity. The circuit  6  and the memory  8  can be implemented in a single component without departing from the scope of the invention. It is also possible for the portable object to have functions in addition to the remotely-powered circuit  6 , such as a controlling function provided by a cell or battery power supply and a high frequency transmission circuit. In this case, the circuit  6  could be powered by the cell or battery under normal running conditions and be powered only by the interrogating circuit if the cell or battery fails. 
   In addition to the portable object  2 , the system has an interrogating circuit  10  provided on the vehicle. This circuit  10  ensures that the portable object  2  is powered when interrogated. In the case of the transponder in  FIG. 1 , powering is provided via a power source  12 , such as an antenna, which transmits a magnetic field used for powering the coil  4  in the object  2  and is modulated for interrogation. More than one antenna could be provided. 
   The power supply  12  is controlled by control logic  14  that controls powering of the portable object  2  during interrogation, the interrogation itself, and the responses furnished by the object  2 . Depending on the response from the object  2 , the control logic  14  may deliver a locking release signal. In one simple case, a memory  16  is provided for storing an identifier. Interrogation of the portable object  2  involves comparing the identifiers in memories  8  and  16 . The control logic  14  then issues the locking release signal if the comparison shows that the identifiers are identical. 
   It is also advantageous for the interrogating circuit  10  to be powered by a standby power supply  18  that is separate from the main power supply of the vehicle. The standby power supply  18  can be a cell, battery, super-capacitor or similar device and is used to overcome failure of the main supply of the vehicle. One can also obviously provide for the circuit  10  to be powered from the main supply of the vehicle or for the standby power supply  18  to only be used as a standby source should the main power supply fail. 
     FIG. 1  also shows an unlocking mechanism  20  for releasing the lock of the vehicle door. In one embodiment, the unlocking mechanism  20  receives a release signal from the interrogating circuit  10  and proceeds with releasing the lock of the door upon reception of the locking release signal. In  FIG. 1 , it can be seen that the unlocking mechanism  20  is powered by a power supply  18 , at least in standby mode. Again, powering of the unlocking mechanism  20  separately from the vehicle main power supply ensures that locking release is possible even if the vehicle&#39;s main supply is faulty. 
   To ensure that the standby power supply  18  is easily manufactured, compact and inexpensive, the unlocking mechanism should have limited power consumption. A first solution involves using an electromechanical lock in which a specific motor provides lock release. In this case, the lock release motor is typically a 6 volt motor with an electric power of 10 W. According to the invention, an electric lock can be used with a mechanical release that can be enabled with the lock. Such a lock is described below with reference to  FIGS. 2–5  and is described in more detail in commonly-assigned, co-pending applications entitled “Automobile Vehicle Lock,” U.S. application Ser. Nos. 10/365,024 and 10/365,010 which are incorporated by reference herein. In this case, the lock release signal initiates enablement of a mechanical release so that the door can be opened mechanically using the handle.  FIG. 6  shows a further example of a lock which is opened electrically with a mechanical release that can be enabled, which can also be used in the inventive system. 
   In both cases, the standby power supply  18  can take the form of a cell, battery, or capacitor supplying a voltage of up to 6 V. This value provides operation of the unlocking mechanism  20 , powering upon interrogation, and interrogation of the portable object  2 . 
   The physical positions of the interrogating circuit  10 , power supply  18  and unlocking mechanism  20  can vary in the vehicle. The only constraint is that the interrogating circuit  10  should be able to supply the portable object  2  with power and be interrogated while the portable object  2  is outside the vehicle. For interrogating a transponder, it is sufficient for the interrogating circuit  10  to be on any non-metal part of the vehicle, such as a door handle, a door surround trim, a protective trim, a rear view mirror shell, an optical device, etc. Other locations, such as the door seal mentioned above, may be preferred for other types of interrogating circuits  10 . 
   Other factors may also be considered in positioning the system components. For example, it is appropriate to provide the wiring between the interrogating circuit  10  and the unlocking mechanism  20  and, if appropriate, to provide the wiring of these two components from the standby power supply  18 . It is advantageous from this point of view to place the various components as close together as possible. This favors installation of the various parts of the system in the door. 
   Installation of the various parts of the system in the door, which is a closed element, further increases security. In such an installation, a break in a circuit at the door for separately powering the unlocking mechanism  20  or for isolating interrogating circuit  10  does not adversely affect door locking operation. More particularly, a break in the door wiring would not prevent either interrogation or release of the lock. 
   The interrogating circuit  10  can also be part of the main door electronics while still preserving a separate standby power supply  18 . This solution makes it possible to dispose of information for controlling lock release, notably in emergency situations. Conversely, if wiring to the other vehicle doors is provided, it may be advantageous to put the interrogating circuit  10  at a central position to limit the total amount of wiring in the vehicle. 
   The system described with reference to  FIG. 1  has the following advantages. It makes locking release possible even if the main supply of the vehicle fails. In view of the very high degree of reliability due to the presence of the standby power supply, it is possible to eliminate the key cylinder on the lock, removing constraints on door design and limiting the possibility of vehicle break-ins through the key cylinder. 
     FIGS. 2 through 6  illustrate one embodiment of the inventive lock, which has an electrical lock release as well as a mechanical release that can be enabled. Mechanical release can be enabled via the interrogating circuit  10  to allow the door to be opened even if the main electrical supply of the vehicle has failed. 
   In the following description, the terms vertical, horizontal, left, right, top and bottom refer to the position of the lock shown in the figures. The positions described are for illustrative purposes and should not be understood as limiting the position of the lock in operation. 
     FIG. 2  is a diagrammatic view of a lock in a closed and locked position according to an embodiment of the invention.  FIG. 2  shows the claw  32 , which is mounted rotatably about axis  34 . Rotation of the claw  32  about the axis  34  in a counter-clockwise direction allows the door to be opened as shown in  FIG. 3  or  5 . The claw  32  is biased clockwise by a spring towards its open position. 
   For the claw  32  shown in  FIG. 2 , the pawl  38  prevents the door from releasing and keeps the claw  32  on a cooperating means (not shown) holding the door in place. The exact shape of the claw  32  and its movement are known and will therefore not be described in detail. The claw  32  and the claw movement can be modified without affecting the operation of the lock. 
     FIG. 2  further shows a pawl lifter  36  and the pawl  38 . The pawl  38  and pawl lifter  36  rotate about an axis  40 . The pawl  38  and pawl lifter  36  can be better seen in  FIG. 3  and have, in one embodiment, an integral construction. Counter-clockwise rotation of the pawl lifter  36  and the pawl  38  about the axis  40  allows the claw  32  to rotate counter-clockwise, consequently opening the lock. 
     FIGS. 3 and 5  show the pawl  38  and pawl lifter  36  in the foreground. The pawl lifter  36  has a substantially circular shape with a first bearing surface  42  and a second bearing surface  44 . Abutment against either one of these bearing surfaces causes the pawl  38  to turn counter-clockwise. The pawl  38  is integral with the pawl lifter  36  and is rotatably driven by the pawl lifter  36  when the pawl lifter  36  turns counter-clockwise. The pawl  38  has a finger portion  46  that contacts the claw  32 , preventing the claw  32  from moving when the lock is closed and locked, in the position shown in  FIG. 2 . Movement of the finger portion  46  allows the claw  32  to rotate, as shown in  FIGS. 3 and 5 . The pawl  38  and pawl lifter  36  are biased by a spring (not shown) toward the closed and locked position shown in  FIG. 2 . 
   A lever  48  for manually or mechanically opening the door (visible in  FIG. 2 ) is rotatably mounted about the axis  40  of the pawl  38 . The lever  48  is connected by an external release cable or rod mechanism  50  to an external release control (not shown). The lever  48  is connected by an inside release cable or rod mechanism  52  to an internal release control (not shown). Operating the external release control or the internal release control brings about rotation of the lever  48  about the axis  40  in a counter-clockwise direction via the cable or rod mechanism  50  or the cable or rod mechanism  52 , respectively. The lever  48  also has a bearing surface  54  for driving the pawl lifter  36  when mechanical release of the lock is selectively engaged, as explained below with reference to  FIGS. 4 and 5 . The lever  48  further has an opening  56 , which will be explained in greater detail below. A spring (not shown) biases the lever  48  counter-clockwise to the closed position shown in  FIG. 2 . 
   A motor  58  for electrically opening the lock can be seen in  FIG. 2 . The motor  58  drives a drive arm  60  in translation along a vertical axis in  FIG. 2 . The motor  58  is electrically powered from the main electrical circuit of the vehicle and is dimensioned to ensure release of the door lock under normal operating conditions. The motor  58  can typically consist of a DC motor of, for example, 40 watts with a no-load speed on the order of, for example, 12,500 rpm. 
   The lock has a release coupling lever  62  to allow release of the lock. The release coupling lever  62  is mounted at an end of an arm  64 . The other end of the arm  64  carries a lug  66  that engages in the opening  56  of the lever  62  discussed above. A spring  68  biases the arm  64  to the left in  FIG. 2 . In the position in which the lock is locked shown in  FIG. 2 , when the lever  48  is in the rest position, the lug  66  bears against the left-hand end of the opening  56  under the biasing action of the spring  68 . The arm  64  and the release coupling lever  62  are then brought back toward the right by the lever  62  to clear the first bearing surface  42  of the pawl  38  and the drive arm  60 . 
   In this position, powering of the motor  58  and movement of the drive arm  60  do not allow the pawl to turn. The release coupling lever  62  consequently provides security against accidental release should motor  58  be accidentally powered. 
   When the inner or external release control is operated, the lever  48  rotates about axis  40  counter-clockwise as shown in  FIG. 3 . In this position, the spring  68  biases the arm  64  to the left, and the release coupling lever  62  adopts a position between the first bearing surface  42  of the pawl lifter  36  and the operating arm  60 . In this position, as explained below, the release coupling lever  62  enables the motor  58  to be powered by closing a contact; its position between the drive arm  60  and the first bearing surface  42  of the pawl  38  allows the door to be opened by powering the motor  58 . 
   If the motor  58  does not operate correctly and if the drive arm  60  moves toward the first bearing surface  42  of the pawl lifter  36  and jams in this position, the opening  56  in the lever  48  still allows the lever  48  to turn. Indeed, if the lever  48  turns, the release lever  62  comes into contact with the arm  60  and its movement becomes blocked. The lever  48  can continue to turn, with the lug  66  moving inside the opening  56  against the bias of spring  68 . The opening  56 , the spring  68  and the lug  66  consequently provide a safety measure against faulty operation of motor  58 . This flexible linkage between the release lever  62  and the lever  48  for manually opening the door prevents the lock from jamming if the motor fails when the arm is in the lower position. 
   Finally, the cylindrical or rounded shape of the release lever  62  facilitates its release under the effect of the recall spring for lever  48  if the drive arm  60  jams in the position shown in  FIG. 4  or  5 . Releasing the release lever  62  avoids, in this case, the lock getting jammed in an open position. 
     FIG. 2  shows elements of the selective coupling mechanism for mechanically opening the lock. This mechanism comprises an arm  70 , which is rotatably mounted about an axis  72 . Movement of the arm  70  about the axis  72  is controlled by a standby motor  74  operating under very low load. The motor allows the arm  70  to turn in one direction or the other for reasons explained below. A selective mechanical coupling finger is mounted on arm  70 . When the standby motor  74  causes the arm  70  to rotate counter-clockwise, the end  78  of the finger  76  moves between the bearing surface  54  of the lever  48  and the second bearing surface  44  of the pawl lifter  36 . Reference numeral  80  indicates a member for guiding the end  78  of the finger  76 . The finger  76  is rotatably mounted on the arm  70  and its end  78  can turn about the axis  40  at the same time as the lever  48  and pawl lifter  36 . 
   Electrical contacts may be provided for operating the lock. A first contact is provided at the external release control and is operated when the user manipulates this control. As explained above, a second contact is operated by the release coupling lever  62 , enabling lock release when it becomes inserted between arm  60  and the first bearing surface  42  of the pawl. In one embodiment, a “door open” contact has a state representing the open or closed state of the door. 
   Under normal conditions, operation of the lock is as shown in  FIG. 3 . This diagram shows how the lever  48  moves if the external or inner release control is operated. The external and inner release controls are similar; the operation of the inner release control is shown in parentheses in the following description. The cable or rod mechanism  50  (or the cable or rod mechanism  52 ) transmits this manipulation of the release control to the lever which turns about second axis  40 , as shown by arrow  90  (or  92 ). Under the effect of rotation of the lever  48 , the release coupling lever  62  is driven to the left from the position shown in  FIG. 2 . As shown by arrow  94 , the release coupling lever  62  gets positioned between the arm  60  and the first bearing surface  42  of the pawl lifter  36 . At the end of the travel of the release coupling lever  62 , the lever  62  operates the second contact. 
     FIG. 3  again shows the movement of arm  60  under the action of motor  58 . On  FIG. 3 , to clarify the description, lever  48  is shown behind the pawl  38  and pawl lifter  36 . Operation of the second contact by the release coupling lever  62  energizes motor  58 , which drives arm  60  towards release coupling lever  62  and the first bearing surface of the pawl lifter  36 , as illustrated by arrow  96 . Under the effect of the drive force of the motor  58  transmitted by arm  60  and release coupling lever  62 , the pawl  38  and pawl lifter  36  are driven counter-clockwise around the second shaft  40 ; this rotary movement is shown by arrow  98  on  FIG. 3 . 
   At the end of the lock release movement, the pawl  38  and pawl lifter  36  turn as shown by arrow  98  and allow the claw  32  to turn. Under the effect of the reaction force of the seal, to which the vehicle door responds, the latter turns counterclockwise, as shown by arrow  100 , and releases the closing cooperating means mounted on the vehicle. The door will then open. 
   Once the door has opened, the “door open” contact changes state. The motor  58  is controlled to bring the arm  60  back to a raised position and the release coupling lever  62  is released. The lever  48  returns to the position of  FIG. 2  when the external release control is no longer applied. The pawl  38  is biased back to the position shown in  FIG. 2  so that closing the door brings the claw  32  and pawl  38  back to the position shown in  FIG. 2 . 
     FIGS. 4 and 5  are views of the lock of  FIG. 2  and illustrate how the various parts of the lock move during mechanical release of the lock. Mechanical release is commanded by a locking release signal delivered by the circuit  10  when the electrical supply of the vehicle is faulty. 
     FIG. 4  is a view of the lock after powering the standby motor  74  to selectively establish coupling for mechanically opening the lock. As shown in  FIG. 4 , operating the standby motor  74  causes the arm  70  to rotate about the axis  72  in a counter-clockwise direction as shown symbolically in  FIG. 4  by arrow  102 . As a result of this rotation, the mechanical release coupling lever  62  moves towards the lever  48  and the pawl lifter  36 . The presence of the guide member  80  helps ensure that the end  78  of the finger is inserted between the bearing surface  54  of the lever  48  and the second bearing surface  44  of the pawl lifter  36 . In the position shown in  FIG. 4 , the lock is enabled with the mechanical release of the lock by operating the inner or external release control, independently of operation of the motor  58 , as explained with reference to  FIG. 5 . 
   It will be understood that the standby motor  74  is simply dimensioned to allow rotation of arm  70  and movement of finger  76 . Because of this, the standby motor  74  can be dimensioned for low loads. In one embodiment, a 10 W DC motor can be used as the standby motor  74  with a no-load speed on the order of 4000 to 6000 rpm. “Power,” as used herein, is the simple product of nominal voltage and the start-up current of the motor and is not representative of the mean power consumed by the motor (the energy consumed by the motor while arm  70  is rotating divided by the duration of this rotation). In practice, the average power consumed by the motor is on the order of 1 W. Because the standby motor  74  has low-power and is only subject to a low load, the standby power supply  18  can be compact and inexpensive, as indicated above. 
     FIG. 5  shows the lock during mechanical lock release. Operating an internal or external release control causes the lever  48  to rotate. Because the end  78  of the finger is present between the bearing surface  54  of the lever  48  and the second bearing surface  44  of the pawl lifter  36 , rotation of the lever  48  causes the pawl lifter  36  to rotate and release the claw  32 ; the movement of the pawl and claw assembly is similar to that described above and will not be discussed again in detail. Arrows  104  and  106  in  FIG. 5  represent the rotary movement of the assembly comprising pawl lifter  36 , the pawl  38  and claw  32 .  FIG. 5  also shows arrows  108  and  110  representing rotation of lever  48  under the action of an external or internal release control, causing rotation of the pawl assembly. 
   The lock of  FIGS. 2 through 5  operates as follows. During normal operation, the lock is opened as explained with reference to  FIGS. 2 and 3 . In this case, when the release coupling lever  62  closes its corresponding contact, as explained above, to start the motor  58  and consequently release the lock. 
   Locking or release of the lock can be conducted solely by software. To ensure that the lock is locked, it is sufficient not to drive the motor  58  even when the contact of release coupling lever  62  is operated. Release of the lock is achieved by enabling the motor  58  to turn via the release coupling lever contact. Under normal operating conditions, a signal indicating release of the lock is delivered by the circuit  10  and simply transmitted to the main electronic circuit for the door, enabling software-controlled release of the lock. 
   Under degraded operating conditions, the lock operates as shown in  FIG. 5 , after coupling has been established between the emergency mechanical linkages, as shown in  FIG. 4 . The degraded operating mode may occur for various reasons, including, for example, failure of the electrical supply to the motor  58 , failure of the motor  58  itself, or a detected emergency condition, such as an airbag or an ABS system deployment. 
   Under degraded operating conditions, the unlocking signal transmitted by circuit  10  commands the standby motor  74  for the lock to couple-in mechanical release of the lock as shown in  FIG. 4 . The unlocking mechanism is now formed from the arm  70 , the standby motor  74  and the finger  76 . As explained above, the motor  74  can be powered by a standby power supply  18 , which ensures unlocking even if the main electrical system of the vehicle fails. 
   The lock of  FIGS. 2–5  consequently allows, for example, software-controlled unlocking of the lock under normal operating conditions, and enabling the mechanical release of the lock even if the main power system of the vehicle should fail. Consequently, it is no longer necessary to provide a key-operated cylinder with the lock. 
     FIG. 6  shows another example of a lock usable in the system of  FIG. 1 . This lock is similar to the one in  FIGS. 2–5 , but instead of only providing a single coupling-in system for the external and internal release controls, a mechanical linkage is used for controlling release from inside the vehicle and an electrical linkage for controlling release from outside the vehicle.  FIG. 6  is a diagrammatic view of the lock in a closed position with security locking in operation. The parts of the lock that are similar to those in  FIG. 2  are indicated with same reference numerals and will not be described again. One will recognize the claw  32 , lever  48 , inner release cable or rod mechanism  52 , pawl lifter  36 , pawl  38 , electric release motor  58  with its drive arm  112 , arm  70 , motor  74 , coupling-in finger  76  and the guide member  80 . 
   Unlike the lock of  FIG. 2 , the lock in  FIG. 6  does not have a release coupling lever with the arm and lug. Consequently, the drive arm  112  of motor  58  bears directly on first bearing surface  42  of pawl lifter  36  when the motor  58  is operated. The shape of the drive arm  112  of the motor  58  is slightly different in  FIG. 6  compared to  FIG. 1  in view of the absence of the release coupling lever. More precisely, the arm  112  has a dimension in its displacement direction that is substantially equal to the sum of the dimensions of arm  60  and the release coupling lever  62 . This avoids the need to modify the degree of travel of motor  58  to ensure release and makes it possible to employ, in the example of  FIG. 6 , the same motor as the motor used in the lock of  FIG. 2 . 
   Furthermore, the lock in this embodiment has no external release cable or rod mechanism  50 . Structurally, the lever  48  is identical to the one shown in  FIGS. 2–5 , but it will be understood that the opening and the part designed to receive the external release cable can be dispensed with in this embodiment. 
   In the state shown in  FIG. 6 , the lock is closed with the security locking or child-proof feature in operation. Like in  FIG. 2 , the coupling-in finger  76  is raised and is no longer between the bearing surfaces  44  and  54  of the lever  48  and the pawl lifter  36 . 
   When the lock is locked, attempts to open the lock using the internal release control causes the various parts of the lock to move in a fashion similar to the way shown in  FIG. 3 . The lever  48  is driven to rotate about the axis  40  by traction from the cable or rod mechanism  52 , as shown in  FIG. 3  by arrow  92 . The bearing surface  54  of the lever  48  approaches the second bearing surface  44  of the pawl lifter  36 . In view of the position of the coupling-in finger  76 , the rotation of the lever  48  is not transmitted to the pawl lifter  36 . Operation of the internal release control consequently does not lead to mechanical release of the lock because the mechanical release is disabled in this case. When the security locking or child-proof feature of the lock is in operation, electric release of the lock will also not be effective. In this case, any attempt to release the lock using the internal release control will not release the lock. 
   Mechanical release of the lock in  FIG. 6  can be enabled. In this state, operating the internal release control mechanically releases the lock. Enablement of the mechanical release is achieved, as shown in  FIG. 4 , by lowering the finger  76  via the motor  74 . The end  78  of the finger is positioned between the second bearing surface  44  of the pawl lifter  36  and the bearing surface  54  of the lever  48 . In this state, when the internal release control is operated, it brings about rotation of the lever  48  about axis  40  via the cable or rod mechanism  52 . The rotation of the lever  48  is transmitted to the pawl lifter  36  via the end  78  of the finger  76 . Rotation of the pawl lifter  36  and the pawl  38  allows the claw  32  to turn in a similar manner as shown in  FIG. 5 . 
   This lock operates as follows. Release of the lock from the external release control is electric and is achieved via the motor  58  and the drive arm  112 , causing the pawl lifter  36  to turn. No cable or rod mechanism going to the lever is provided in this embodiment. In this way, it is not necessary to fit the vehicle door with an external release control or a lock cylinder for introducing a key. If needed, power supply redundancy may be employed along with redundancy of the sensor or software to further ensure reliability of lock release. Locking and unlocking of the lock are purely software operations in this case and do not involve any mechanical elements. 
   Lock release from the internal release control is conducted mechanically. In the locked state or with the security locking or child-proof feature in operation, the finger  76  is in the raised position shown in  FIG. 6 . Operating the internal release control shifts lever  48  but has no effect on the pawl  38  and pawl lifter  36 . When the lock is unlocked and if the child-proof feature is not in operation, the finger  76  is in the lower position. Operating the finger  76  acts on the pawl lifter  38  and pawl  38  to release the lock. 
   Lowering the coupling-in finger  76  has the effect of releasing the security locking feature or de-activating the child-proof feature of the lock. As a result, the lock has a purely electrical external release feature and a purely mechanical internal release feature, with a mechanical release that can be enabled to provide security locking or set the child-proof feature. Like in the example of  FIGS. 2–5 , the lock in  FIG. 6  reduces problems caused by diverse lock models and it eliminates the need for a standby power supply in the door. The lock of  FIG. 6  also makes it possible to simplify the door structure because no mechanical linkages between the external release control and the lock are required. External release control members can even be eliminated by using sensors other than the external release control sensor described in the example. 
   In the example shown in  FIG. 6 , the unlocking signal sent by the interrogating circuit  10  for the portable object  2  consequently brings about software unlocking, allowing electrical release of the lock. The portable object can, for example, be triggered when the user approaches the vehicle or manipulates the external release control. The unlocking signal further enables mechanical release of the lock from the internal release control. In other words, the mechanical unlocking system formed by the motor  74 , the arm  70  and the finger  76  is operated to allow mechanical release of the lock from the internal release control. 
   Like in the example shown in  FIGS. 2–5 , the lock shown in  FIG. 6  reduces the problems caused by diverse lock models and limits the need for a standby power supply in the door. It also allows the door structure to be simplified because the door structure no longer needs to accommodate mechanical linkages between an external release control and the lock. The invention can also dispense with external release control members by using sensors other than the sensor for external release control. Alternative embodiments can be provided; thus, for a door implementing a child-proof feature, the unlocking signal may not bring about enabling of mechanical release from the internal release control. This ensures that the door having the child-proof feature set will remain in this state even when the interrogating circuit is issuing an unlocking signal. 
   For the lock in  FIG. 6 , it is advantageous for the finger  76  to be located between the bearing surfaces  44  and  54  in the rest position. This avoids the need to provide a standby power supply for the motor  74  in the vehicle door. Indeed, if the security locking release finger  76  is in the upper position in its rest state, it is preferable to provide a standby power source, such as a battery, capacitor, or similar energy storage device in the door of the vehicle to enable the mechanical release even in post-impact conditions. Conversely, if the security locking release finger  76  is in the rest state in its lowered position, it is possible to implement security locking of the lock or a child-proof feature as soon as the vehicle starts, without providing a standby power source. For this, it is sufficient to raise the security locking release finger  76  using the vehicle battery. If the security locking release finger  76  is always left in the lower position on the driver&#39;s door, in other words, if security locking of the driver&#39;s door is not allowed, there always remains one door that can be opened via the internal release control, even in the case of an accident. 
   An alternative to the embodiment shown in  FIG. 6  is a modification of the embodiment shown in  FIGS. 2–5 . In this alternative embodiment, one could provide, in the example of  FIGS. 2–5 , electrical release via motor  58 , which is initiated by movement of the internal release control or movement of the lever. In this case, the effect of operating the internal release control would be to initiate electrical release. This solution provides electrical release of the lock from the internal release control. This embodiment requires the presence of a standby power source for lowering security locking release finger  76  if the electrical release fails to allow the lock to be opened mechanically at least via the internal release control, but such a power supply is already provided for the interrogating circuit. Thus, if electrical release from the internal release control is provided, the unlocking signal sent from the interrogating circuit also has the effect, for the internal release control, of enabling rotation of a motor  58 . This does not cause finger  76  to descend. 
   Another alternative is to provide electrically-assisted release from the internal release control. In this case, when locking is released in the absence of security locking or the child-proof feature, the security locking release finger  76  is in a lower position. Operating the internal release control shifts the lever and initiates lock release via the motor. This solution has the disadvantage of mechanically-assisted release and, in particular, the risks accompanying rough operation of the internal release control. However, it also avoids the need to provide a standby power source in the door and allows a very low-powered motor  74  to be used for operating security locking release finger  76 . In this case, the unlocking signal sent from the interrogating circuit authorizes operation of the motor  58  when the internal release control is operated, but additionally causes the finger  76  to descend. 
   Another problem with currently known locks is the diversity of lock models. In effect, a key cylinder is generally only provided on the front doors, but not on the rear doors of a vehicle. The use of the system in  FIG. 1  can reduce this diversity by eliminating the need to provide a mechanical key locking cylinder. 
   In all of the examples described, a standby power supply can be provided as indicated above to power the vehicle&#39;s interrogating circuit and/or coupling in of the mechanical release of the lock. In the presence of such a standby power supply, one can cause mechanical release to be enabled even if the vehicle power supply fails, thereby allowing mechanical release of the lock either via the external release control and the internal release control (in the example of  FIGS. 2–5 ), or via the internal release control (in the example of  FIG. 6 ). In all cases, the energy required is small because the only actions required to be powered is the coupling in of the mechanical release and not actual release of the lock. If enablement of the mechanical release via the standby power supply is thus possible, sensors on the internal opening control or external opening control can be used for waking up the interrogating circuit electronics or the electronic circuitry associated with the lock if the main power supply of the vehicle fails. 
   Standby electronic circuitry can also be provided. The standby electronic circuitry should consume minimal power and have only a limited number of functions, including enabling the mechanical release. The standby electronic circuitry has a signal line to the vehicle battery or at the least receives a signal representing the presence of powering from the main vehicle battery. Further, the standby electronic circuitry is powered by the standby power supply and is capable of monitoring sensor status on the internal opening control or external opening control, or receive signals that represent the state of these sensors. The standby electronic circuitry is inactive as long as the vehicle battery is supplying power. If the vehicle battery ceases to provide a supply voltage, the standby electronic circuitry will be woken up by signals originating from the sensor to allow enabling of the mechanical release. Waking up of the standby circuitry by signals from the sensors ensures that the standby electronic circuitry will not consume power from the standby power source under normal operating conditions. The standby electronic circuitry can then be built into a circuit board that includes the standby power supply. The standby electronic circuitry will now include a logic circuit adapted to analyse signals received from the sensors and a changeover switch able to power up coupling-in of mechanical release from the standby power supply. 
   Obviously, the invention is not limited to the embodiments described by way of example. In particular, portable objects other than a transponder can be used; the above description does not exclude implementations in which the functions are implemented differently. The examples mention electric motors for providing unlocking via a signal supplied by the interrogating circuit, but other types of actuator could be used for unlocking, such as pneumatic actuators. 
   The various circuits or software for controlling the lock are not described in detail; they can be provided by those skilled in the art, using components known in the state-of-the-art. 
   In the examples described above, the invention has been described in its application to unlocking of a door; it can apply more generally to all opening components of a vehicle, including the vehicle trunk. The examples described above cover the simplest case in which the interrogating circuit supplies an unlocking signal to the lock of a door of the vehicle. It is also possible for the interrogating circuit to supply an unlocking signal to more than one lock, for example all the locks of the vehicle under normal operating conditions. 
   It should be understood that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention. It is intended that the following claims define the scope of the invention and that the method and apparatus within the scope of these claims and their equivalents be covered thereby.