Abstract:
A lock system for a vehicle, including an authentication module for receiving authentication code transmitted from a remote electronic key and for generating an authentication signal, and an ignition lock assembly having an ignition switch unit, a part movable between at least first and second positions to activate the ignition switch unit, an electronic lock module responsive to the authentication signal for generating a lock release signal, and a lock mechanism which inhibits use of the vehicle and in response to the lock release signal enables use of the vehicle.

Description:
FIELD OF THE INVENTION 
     The present invention relates to a lock system for a vehicle. 
     BACKGROUND INFORMATION 
     Most ignition lock systems for vehicles require an ignition key with a mechanically coded shaft to be inserted into a lock barrel and rotated to activate an ignition switch of the system. Only a mechanically coded key that corresponds to the lock barrel can be used to activate the ignition switch and start the vehicle. The mechanical lock assemblies used in the ignition locks are relatively expensive to implement and provide less security than that which is available with electronic systems used for vehicle entry. Accordingly, it would be advantageous to provide an ignition lock system which alleviates or minimizes these disadvantages or at least provides vehicle manufacturers with a useful choice. 
     SUMMARY 
     In accordance with the present invention, a lock system for a vehicle, is provided. The lock system includes 
     an authentication device for receiving authentication code transmitted from a remote electronic key and for generating an authentication signal. The lock system further includes 
     an ignition lock assembly having: 
     an ignition switch unit; 
     a part movable between at least first and second positions to activate the ignition switch unit; 
     electronic lock means responsive to the authentication signal for generating a lock release signal; and 
     a lock mechanism which inhibits use of the vehicle and in response to the lock release signal enables use of the vehicle. 
     The present invention further includes an electronic system for an ignition and steering lock assembly. The electronic system includes: 
     an authentication device for receiving authentication code transmitted from a remote electronic key and for generating an authentication signal. An electronic lock device of the assembly is responsive to the authentication signal for generating a lock release signal to release a lock mechanism of the assembly. An ignition switch unit of the assembly generates signals representative of the position of movable part of the assembly for the electronic lock assembly, the part being movable between at least first and second positions to activate the ignition switch unit. 
     The present invention further provides a lock system for a vehicle, including: 
     a steering lock tongue which is biased to actuate a steering lock mechanism; 
     a lock mechanism for preventing movement of the lock tongue to actuate the steering lock mechanism; and 
     an electronic lock device for controlling the lock mechanism, so that the lock tongue is released and is able to engage the steering lock mechanism when predetermined data is received. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is an isometric, partial cross-sectional, view of an example embodiment of an ignition lock assembly of an ignition lock system. 
     FIG. 2 is a partial cross-sectional view of the ignition lock assembly. 
     FIG. 3 is a block diagram of the ignition lock system. 
     FIG. 4 is an isometric, partial cross-sectional, view of another example embodiment of a lock assembly. 
     FIG. 5 is a block diagram of the lock assembly of FIG.  4 . 
     FIG. 6 is a block diagram of part of the assembly of FIG.  4 . 
     FIG. 7 is a block diagram of an alternative lock tongue of the assembly of FIG.  4 . and 
     FIGS. 8 to  10  are schematic diagrams showing the different positions of the alternative lock tongue for different states of the lock assembly of FIG.  4 . 
    
    
     DETAILED DESCRIPTION 
     An ignition and steering lock assembly  4  of an ignition lock system, as shown in FIGS. 1 and 2, includes a standard ignition switch  6 , a standard steering lock mechanism, having a lock tongue  8 , and a rotary knob  10  which can be rotated between an OFF position  12 , an ACC position  14  and IGN position  16  and a fourth optional and momentary START or CRANK position  17 . The mechanical lock mechanism, which includes a lock barrel is however removed. The mechanical lock mechanism normally prevents movement of rotary knob  10 , unless a corresponding mechanically coded key is inserted into assembly  4 . Assembly  4 , instead, includes a solenoid  18  with a movable locking plunger  20 , which when extended prevents movement of rotary knob  10  between the OFF and ACC positions  12  and  14 , unless vehicle access authorization is proven. Solenoid  18  is seated within the housing of assembly  4 . Plunger  20  of solenoid  18  is spring loaded, which leaves the plunger in an extracted position when the solenoid is not energized. 
     When solenoid  18  is activated or energized, on access authentication, locking plunger  20  is retracted to allow rotary knob  10  to be moved between OFF and ACC positions  12  and  14 . Rotary knob  10  is coupled by a shaft mechanism  22 , as shown in FIG. 2, to ignition switch  6 , so that rotation of knob  10  to IGN position  16  or optional START position  17  will activate ignition switch  6 , initiate driver authentication and start the vehicle if driving authorization is proven. 
     The rotary knob  10 , as shown in the Figures, includes a rear recessed portion  24  for receiving locking plunger  20  in OFF position  12 . Once the vehicle has been started, rotary knob  10  is held in the START position, until a person positively switches off the vehicle by returning knob  10  to ACC or OFF positions  14  or  12 . To proceed from ACC position  14  to OFF position  12  a push and turn movement is required. More particularly, knob  10  is pushed in while in ACC position  14  and then turned to OFF position  12  to enable steering lock activation. The vehicle is then locked by an electronic key  40 , which may be a remote key, smart card or transponder of a passive entry system, to deactivate solenoid  18  via messages issued from a door lock module  30  to an ignition lock module  32 , as described below. Key  40  can include two communication protocols, one for enabling vehicle entry and solenoid  18  to be energized, and a more secure protocol for communicating with the electronic system to enable starting of the vehicle, i.e., driver authentication. 
     An electronic system, as shown in FIG. 3, includes a door lock control module  30  having a code reader or transceiver, an ignition lock control module  32  for solenoid  18 , a driver authorization reader or transceiver  39 , which are connected by a bus system or Local Area Network (LAN)  34  within the vehicle. Bus system  34  also connects code reader  30  to the vehicle&#39;s Engine Management System (EMS) module  36  and a siren or sounder module  41 . Ignition switch  6  generates switch position outputs  38 , representative of the position of knob  10 , which are coupled to ignition lock control module  32 . These switch position outputs  38  are processed by ignition lock control module  32  and then made available to bus system  34  as status messages. Door lock module  30  communicates with key  40  to obtain an access authentication code which allows rotary knob  10  to be turned. Module  30 , on interrogating the electronic key for the access authentication code, exchanges code, which may be encrypted, with EMS module  36  and ignition lock control module  32 . Actuation of a door handle switch  37  of the vehicle will cause access interrogation to occur. Ignition lock control module  32  includes processing circuitry to validate the access authentication code, which may involve executing a decryption procedure. On validating access authentication code module  32  generates a drive signal for solenoid  18  to retract plunger  20 , as shown in FIG.  3 . This allows knob  10  to be turned and ultimately the vehicle to be started by turning knob  10  to ACC position  14  and then IGN position  16  or the optional START position, provided driving authorization is obtained. 
     The electronic key  40  may be implemented as remote control key with activation buttons or as a key or smart card without buttons in a passive entry system. Key  40  can rely on a communication signal by activation of switch  37  for activation of the communications protocol. 
     Access authorization and driving authorization are granted in two separate steps for reasons of theft security as well as operational safety. Access authorization affects solenoid  18 , while driving authorization affects the success of an attempt to crank the engine of the vehicle. Once the engine is running, no authorization checks are required. During the authorization, key  40  needs to be within proximity of reader modules  30  and  39 . The example sequence of steps for unlocking, driving and locking the vehicle is as follows: 
     1. Activate an access authentication procedure by a button of key  40  or activating door handle switch  37 . Door module  30  sends an encrypted authentication message. Ignition lock module  32  receives the access authentication message and activates solenoid  18  to retract its plunger  20  for release of rotary knob  10 . 
     2. The rotary knob  10  is pushed in and turned from OFF position to ACC position  14 . 
     3. The rotary knob is turned from ACC position  14  to IGN position  16  or optional START position  17 . The ignition signal feed provides an activation signal to module  39  to activate the driving authentication procedure. If driving authorization is proven module  39  places a driving authentication message on bus system  34  where it activates EMS module  36  causing it to start (crank) the engine. 
     4. When rotary knob  10  is turned from IGN position  16  to ACC position  14 , the engine stops. 
     5. The knob  10  is pushed in while in ACC position  14  and turned to OFF position  12  to engage steering lock mechanism  8 . 
     6. The vehicle is locked using a button on key  40  or door handle switch  37 . This deactivates solenoid  18  via a bus message issued by door lock module  30  and sent to ignition lock module  32 . The spring mounted in the solenoid pushes plunger  20  into the rear recessed receptacle  24  of rotary knob  10 . This ensures knob  10  is locked if the vehicle is not driven after vehicle access. 
     If step 5 is missed by moving directly from step 4 to step 6, a warning signal is emitted and/or the door lock system will not activate. This prompts a user of the vehicle to return and execute step 5. Ignition lock control module  32  uses switch position outputs  38  to determine ignition lock status and a bus message can be output if it receives a lock message from door lock module  30  that does not conform or comply with current position of switch  6 . This bus message is directed to door lock control module  30  and/or sounder module  41  for action. Door lock module  30  may ignore a request for actuation. 
     An alternative lock system  104 , as shown in FIGS. 4 to  10 , removes any requirement to provide a warning signal for actuation of the steering lock mechanism as it is automatically activated when the engine is turned off, the vehicle at rest and the doors locked. Alternatively, the steering lock mechanism can be engaged when it is detected that the doors are locked and electronic key  40  is out of range of reader modules  30  and  39 . 
     The ignition and steering lock assembly  104  again does not include any mechanical ignition lock mechanism, as the lock barrel is removed, and again there is no provision whatsoever for insertion of a coded shaft ignition key into rotary knob  110 . Also solenoid  18  for rotary knob  10  is replaced by an electromechanical blocking mechanism (EMB)  88  with a spring loaded plunger  86  which acts on lock tongue  80 , as described below. EMB  88  may be a solenoid or a driven motor. Accordingly, there is no recessed portion  24  in knob  110 . For ignition lock assembly  104 , there is also no OFF position. Rotary knob  110  of assembly  104  is able to move between an ACC position  12  and an IGN position  14 , and can also be moved from IGN position  14  to an optional and only momentary START or CRANK position  16 . 
     Automatic actuation of the steering lock mechanism is provided by incorporating in assembly  104  steering lock tongue  80 , which is the same as lock tongue  8  in that it is spring loaded by a bias spring  82 , except that it includes a side wall cavity  84 , as shown in FIG.  6 . Side wall cavity  84  is for receiving plunger  86  of EMB  88  which is electrically connected to lock module  32  for activation. When the driver is inside the car with the engine running, the steering lock mechanism will be disengaged and lock tongue  80  will be in the position, position A, as shown in FIG.  6 . EMB  88  under the action of a bias spring  90  will cause plunger  86  to engage tongue  80  within cavity  84  so as to hold tongue  80  in position A. Tongue  80  can therefore only be released to engage the steering lock mechanism, by energizing EMB  88  and retracting plunger  86 . Ignition lock module  32  will instruct this to occur when it detects that rotary knob  10  has been moved from IGN position  14  to ACC position  12 , and module  32  also receives a signal or signals to indicate (1) the doors of the vehicle have been locked, and (2) the vehicle speed is zero. Lock tongue  80  will then be released to engage the steering lock mechanism under the action of tongue bias spring  82 . Tongue  80  will move to position B indicated by dotted lines  92 , when the steering wheel is not centered, and will then move to position C indicated by dotted lines  94 , when the steering wheel does become centered. This ensures the steering lock mechanism can be engaged after a driver turns off the engine, the vehicle is stationary, and the doors have been locked. The steering lock mechanism can subsequently be released, as discussed previously, by pushing in and moving rotary knob  10 . 
     Advantageously, lock assembly  104  can be configured so that the steering lock mechanism is mechanically linked to shaft  22  for movement of rotary knob  10 , such that when lock tongue  80  is released to engage the steering lock mechanism, this also simultaneously invokes a lock mechanism to prevent movement of rotary knob  10 , as described below. 
     For secure electronic release of rotary knob  10  and the steering lock mechanism, tongue  80  can be configured to include an additional cavity  85 , as shown in FIG. 7, which is lower than first cavity  84 , so that plunger  86  is received by lock tongue  80 , when it is engaged in position C with the lock mechanisms engaged. This will ensure that the lock mechanisms can only then be released after an electronic release procedure involves EMB  88  being energized. 
     With lock tongue  80  including two cavities  84  and  85 , as shown in FIGS. 8 to  10 , while the vehicle is being driven, EMB  88  will have its plunger  86  engaging first cavity  84  so tongue  80  is in position A, as shown in FIG.  8 . With lock tongue  80  in position A, the driver is free to move rotary knob  110  from IGN position  14  to ACC position  12  to turn off the engine. When, as described previously, the doors of the vehicle have been locked and the vehicle speed is zero, ignition lock module  32  will instruct EMB  88  to retract plunger  84  so as to release tongue  80  so it can move under the action of bias spring  82  to position B or C, depending on whether the steering wheel is centered. On subsequently entering the vehicle, the steering wheel is centered or is moved so as to become centered, lock tongue  80  will be in position C, as shown in FIG. 10, and the steering wheel lock mechanism will be engaged. With the steering lock mechanism also linked to the lock mechanism for rotary knob  110 , it will not be possible to move rotary knob  110  from ACC position  12  to IGN position  14  or start position  16 . In position C, plunger  86  of EMB  88  is extended by the action of its bias spring  90  so as to engage second cavity  85 , thereby locking tongue  80  in position C. Accordingly, steering wheel nor rotary knob  110  of the vehicle can be moved unless the following release procedure is correctly executed. The release procedure involves: 
     (i) pushing in rotary knob  110  to initiate execution of the driver authentication procedure. 
     (ii) the ignition lock  132  detects pushing in of lock module  110  and instructs driver authorization reader  39  to interrogate electronic key  40 . 
     (iii) when driver authorization is proven following execution of the driver authentication procedure, a positive message is passed to ignition module  32 . 
     (iv) the ignition lock module  32  instructs EMB  88  to retract plunger  86 , and the steering mechanism and ignition lock mechanism can be released by pushing in and turning rotary knob  110  and turning the steering wheel of the vehicle. 
     If desired, a second EMB can be included to act on the lock mechanism for rotary knob  110 . 
     Many modifications are possible to those skilled in the art without departing from the scope of the present invention as hereinbefore described.