Lock latch

A door latch assembly comprising an elongate latch housing having one end with a face plate, a latch tongue in said housing, spring means in the housing urging the latch tongue to project from said one end of the housing, an actuating mechanism in said housing for withdrawing the latch tongue into the housing against the force of the spring means, the actuating mechanism including an actuating plate, connector means between the plate and the latch tongue, an actuator wheel rotatably mounted in said housing about a doorknob axis perpendicular to a longitudinal axis of the housing, means on said actuator wheel for attaching a doorknob to rotate the actuator wheel about the doorknob axis, a projecting tooth formed on said actuator wheel, and a pulling lever pivotally mounted in said housing on a pivot axis parallel to said doorknob axis, said pulling lever having a projection to be engaged by said tooth when the actuator wheel is rotated in one direction, said lever further having a lever arm longer than said tooth engaging in an aperture in the actuating plate so that rotation of the actuator wheel in said one direction from a rest position provides pivotal motion of the lever through engagement of said tooth and said projection effective to cause said lever arm to move the actuating plate lengthwise in the housing and withdrawn the latch tongue into the housing against the force of the spring means, and so that release of the actuator wheel enables the spring means to return the actuator plate and latch tongue, the lever and the actuator wheel to the rest position.