Patent ID: 7717480
Filing Date: 2010-05-18
Classification: E05B,E05C,Y10S,Y10T

Abstract:
1. A latch assembly, comprising: a latch bolt; a housing; a spindle; two fixing bolts; a lower connecting plate connected with the housing and having a lower long hole formed on a middle portion of the lower connecting plate for the spindle to pass through, a first hole and a second hole formed on front and back ends of the lower long hole for the fixing bolts to pass through, and a third hole formed on a front portion of the lower connecting plate; an upper connecting plate having an upper long hole formed on a middle portion of the upper connecting plate for the spindle to pass through, a first pair of symmetrical recesses located near two edges of the upper connecting plate across a front portion of the upper long hole, a second pair of symmetrical recesses located near the two edges across a back portion of the upper long hole, a first hole and a second hole formed on front and back ends of the upper long hole for the fixing bolts to pass through, and a third hole formed on a front portion of the upper connecting plate; an actuating plate between the upper and lower connecting plates, the actuating plate passing through the housing, connected with the latch bolt, and having a long slot along a longitudinal direction of the actuating plate with two lower symmetrical protrusions projected from a bottom surface on two edges of a middle portion of the long slot towards the lower connecting plate; a driving plate mounted between the actuating plate and the lower connecting plate, the driving plate having a square hole for the spindle to pass through, and the two lower protrusions of the actuating plate being received in the square hole with a front side wall of the square hole in contact with the lower protrusions of the actuating plate; and a positioning casing in which the upper connecting plate assembled with the lower connecting plate is disposed, the positioning casing having a middle hole on a middle portion thereof for the spindle to pass through, a front hole and a back hole on front and back ends for the two fixing bolts to respectively pass through and two protrusions formed near two edges on the positioning casing across from one another on either side of the middle hole for engaging with the first or second pair of symmetrical recesses of the upper connecting plate; wherein when the protrusions of the positioning casing are engaged with the second pair of recesses of the upper connecting plate, the middle hole of the positioning casing is aligned with the upper long hole of the upper connecting plate, the long slot of the actuating plate and the lower long hole of the lower connecting plate, and the front hole of the positioning casing is aligned with the first hole of the upper connecting plate and the first hole of the lower connecting plate to position the spindle behind the driving plate so that the spindle does not pass through the square hole so that when the spindle is rotated, it will directly move the actuating plate in order to retract the latch bolt; and when the protrusions of the positioning casing are engaged with the first pair of recesses of the upper connecting plate, the middle hole of the positioning casing is aligned with the upper long hole of the upper connecting plate, the long slot of the actuating plate, the square hole of the driving plate and the lower long hole of the lower connecting plate for the spindle to pass through the square hole so that when the spindle is rotated, it will directly move the driving plate to move the actuating plate in order to retract the latch bolt, and the front hole of the positioning casing is aligned with the third hole of the upper connecting plate and the third hole of the lower connecting plate.