Patent ID: 6640871
Filing Date: 2003-11-04
Classification: E06B

Abstract:
An endless loop lock comprising:(a) a drive wheel adapted to be driven at a drive speed, wherein the drive wheel has a resistance to rotation at a speed different from the drive speed; (b) an endless loop engaging the drive wheel at a first portion on the endless loop, wherein the endless loop is adapted to be driven by the drive wheel to move a device connected to the endless loop; (c) a guide biased against a second portion of the endless loop at a position spaced apart from the drive wheel; (d) a lock for engaging the endless loop to inhibit movement of the endless loop, the guide being positioned to bias the endless loop out of engagement with the lock when the endless loop is driven by the drive wheel; (e) wherein the lock may be actuated by a force on the device connected to the endless loop, when the force urges the endless loop and the device connected to the endless loop to move against the resistance to rotation provided by the drive wheel so as to exert a tension on the second portion of the endless loop, and the tension on the second portion of the endless loop is sufficient to displace the guide so that the endless loop engages the lock.