Abstract: A dead bolt lock automatically blocks the extended bolt to prevent externally-applied force from thrusting the bolt back into the lock case, and in the event of physical attack the lock responds by prolonging or perpetuating the dead bolt blocking condition. A push-pull lock has a bolt whose motion in both directions is stopped in response to detection of a rise in motor current above a certain level: a cushioning arrangement allows the current-limiting feature to be implemented without risk of damage to the motor, gear teeth or other drive components. A re-locker arrangement includes an angled flange that is part of a motor-supporting bracket; when forcibly pressed, the flange breaks plastic pins to release a spring-biased re-locker wire to block the bolt from being withdrawn, and when the wire is in the dead bolting position an extension of the re-locker wire engages a ridge in the lock's case to prevent the re-locker from being manipulated back to its original position.

Abstract: A dead bolt lock automatically blocks the extended bolt to prevent externally-applied force from thrusting the bolt back into the lock case, and in the event of physical attack the lock responds by prolonging or perpetuating the dead bolt blocking condition. A push-pull lock has a bolt whose motion in both directions is stopped in response to detection of a rise in motor current above a certain level: a cushioning arrangement allows the current-limiting feature to be implemented without risk of damage to the motor, gear teeth or other drive components. A re-locker arrangement includes an angled flange that is part of a motor-supporting bracket; when forcibly pressed, the flange breaks plastic pins to release a spring-biased re-locker wire to block the bolt from being withdrawn, and when the wire is in the dead bolting position an extension of the re-locker wire engages a ridge in the lock's case to prevent the re-locker from being manipulated back to its original position.