In old cars, doors are locked and unlocked from inside the vehicle by pulling or pushing a door tab connected to a Bowden cable that manually operates the unlocking mechanism. This has been largely done away with in modern cars, which feature electric locks and provide a cable-actuator only as an emergency backup for when the lock fails or service personnel has to operate it with the battery disconnected.
The problem is that if the cable mechanism can be accessed from outside the vehicle and manipulated through the window shaft or door frame, someone can unlock the car and gain unauthorized access. Audi’s recent patent application with the European Patent Office is smart in that the backup cable will break and not unlock the car if accessed this way.
Audi’s Patent Is Tamper-Proof
Audi’s solution is simple and retains the cable connection between the unlocking mechanism and an access point in the car door, where the other end can be grasped to operate it. The operating mechanism is placed in line with the cable and pulls the cable along its longitudinal axis to trigger the unlocking device, but it has a portion in the middle that will fail and cause a break in the cable if it’s pulled in any other direction.
In this way, Audi ensures that if the mechanism is accessed with any device forced into the door housing from the outside, and the cable is pulled on in any other direction than the way its built-in lever is designed to, it will break at the predetermined point. It will then become disabled, failing to unlock the door and not granting access to a would-be intruder. This eliminates the weakness of easily manipulatable manual systems when the electrics don’t work.
Covers All The Bases
Audi’s patent is unique in providing a cable-operated backup mechanism to unlock the door from the inside when the electrical lock doesn’t work, but with a fool-proof design that cannot be manipulated from the outside, even if an intruder gains access to the cable. It argues that this is the best interim manual solution until a suitable electrical emergency unlocking device with reliable backup power has been designed.
