Patent ID: 7895865

Claim:
A cylinder lock assembly comprising: a cylinder plug that is rotatable about its longitudinal axis, the cylinder plug having a front end and a rear end; one or more tumbler shafts arranged radially within said cylinder plug; a tailpiece adapted to operatively couple said cylinder plug to a deadbolt or door latch actuator and configured so as to be rotatable with the cylinder plug about the longitudinal axis when the tailpiece is connected to the cylinder plug; a tailpiece connector adapted to connect said tailpiece with said cylinder plug, wherein the tailpiece connector comprises a tailpiece retainer plate coupled to the tailpiece and at least one fastener element extending through a fastener hole formed through the tailpiece retainer plate and into a fastener-receiving hole formed in the cylinder plug; and a coupling element rotationally coupling the tailpiece to the cylinder plug and comprising an anti-rotation element extending axially into the rear end of the cylinder plug at a location offset from the longitudinal axis of the cylinder plug, wherein said anti-rotation element extends axially toward the front end of the cylinder plug and beyond a tumbler shaft disposed closest to the rear end of the cylinder plug so as to prevent the tailpiece from rotating about the longitudinal axis independently of the cylinder plug when said fastener element is altered so that the tailpiece is not connected to the cylinder plug.