Patent ID: 7350836

Claim:
In a security system for constraining the degree to which a door leaf may be opened of the type having an inoperative position in which it does not block the opening and closing of the door leaf, and an operative door leaf blocking position in which it does so block the opening of the door leaf beyond a predetermined constrained degree and means for selectively activating said system for effecting movement between said inoperative and operative position, the improvement comprising: a chassis; means for mounting said chassis adjacent an opening edge of said door leaf; an electric actuator comprising a motor having a rotatable output shaft; means for mounting said electric actuator on said chassis; an arm operating in response to movement of said output shaft of said actuator, whereby said actuator drives said arm without any lost motion mechanism into and out of said operative position, at least a portion of said arm when in said operative position is moved into a position beyond said chassis, where said arm acts as a barrier to said door leaf being opened beyond a predetermined degree; and means for mounting said arm directly on said output shaft of said motor, so that when said motor shaft rotates, said arm rotates with it, and wherein said arm movement into and out of its operative door leaf blocking position is effected solely by the rotation of said output shaft with essentially no other arm-urging means being deployed.