US 5,083,122 AGranted

Programmable individualized security system for door locks

AssigneeOSI Security Devices

InventorKeith S. Clark

Life of this patent

Estimating the term…

Loading patent…

Abstract

A battery-powered security device for controlling access through a door by authorized uses which includes a lock operated by a low power driven motor; a keyboard by which a user enters codes or programming; a programmable circuit including a microprocessor, data memory and program memory. The device opens the lock in response to a correct code entered through the keyboard and/or to a chronological schedule enabled by a clock marking real time. An LED provides a wireless link to a hand-held printer so that the device may be programmed with access codes and time schedules and prints out a list of users and times of entry. The operative programs in memory can be added or modified by means of the keyboard. The coupling between the motor shaft and key plunger is designed to avoid accidental misuse such as a user holding the door handle while the motor is turning. The entire package--motor, lock, battery and circuitry,--is contained within a compact package approximately equal in maximum dimension to the length of a door handle and attaches to the door in the region of the handle with no additional modification of the door than is required for standard lock installations.

Claims21

Dependent claims

A locking device comprising in operative combination:

a) a locking mechanism having a first locked position and a second unlocked position;
b) a plunger member having a central axis, said plunger being disposed in engagement with said locking mechanism to move said mechanism alternately into said locked and unlocked positions upon reciprocating linear motion of said plunger along its central axis;
c) a motor having a shaft which is disposed coaxial with said plunger axis;
d) means comprising a helical spring for coupling said motor shaft to said plunger, said coupling means being disposed to move said plunger linearly to said locked position when said motor shaft rotates in one direction, and move said plunger linearly toward said unlocked position when said motor shaft rotates in an opposite direction, said spring having a first fixed end and a second free end portion and said coupling means further includes:
i) means for engaging said second free end portion of said spring disposed to contact individual coil faces of said spring;
ii) said spring engaging means advances along said spring coil faces when said motor turns, to convert rotational motion of said motor shaft to linear reciprocating motion of said plunger, to move said plunger to said locked position when said motor turns in one direction and to said unlocked position when said motor turns in an opposite direction;
and
e) said coupling means permitting said motor shaft to continue rotational motion when said plunger is prevented from linear movement in response to an obstruction, and said coupling means stores energy to permit said plunger to complete its normal linear movement to said locked or unlocked position when said obstruction is removed.

5 more elements

Dependencies are inferred from the claim text.