GB1000609A - Door bolt mechanism and keeper - Google Patents

Abstract

1,000,609. Latch fastenings. S. B. MCKENZIE. Oct. 26, 1962; No. 40631/62. Heading E2A. A door bolt mechanism and keeper comprises a containing chamber 4 adapted to be inserted in the edge of a door 1, a spring loaded bolt 28 slidable therein, a bolt draw bar 25 mounted for longitudinal sliding movement in the chamber and operatively connected by one end to the bolt, a rack 18 secured to the other end of the bolt draw bar, a pinion 10 journalled for rotation within the chamber and engaging the rack, handle means mounted at right angles to the chamber, a spindle 11 secured to the pinion and extending through the chamber to mount the handle means and a dead bolt cross bar 34 mounted transversely for movement in the extending end of the bolt and means co-operating between the bolt draw bar and the dead bolt cross-bar adapted to extend one end of the dead bolt cross-bar when the bolt is extended and to permit retraction of the dead bolt cross bar when the bolt is retracted. In the construction shown, when the door is open the bolt is retained in a semi-retracted position by the engagement of a head-piece 23 attached to the rack with the right hand side of a spring loaded cam 36. Shutting the door engages the bolt with the keeper and retracts it further, this causes a pin 45 on the bolt to pivot the cam to release the head-piece 23, the bolt thus moves to its extended position under the urge of its spring 40. There is a lost motion, pin and slot, connection between the draw bar 25 and the bolt and when the bolt reaches its extended position, the draw bar continues to move under the urge of a spring 53 in the handle sleeve 48 via the rack and pinion, the end of the draw bar engages a recess 35 in the dead bolt cross-bar and moves it to its extended position. To release the door, the handle 17 is turned clockwise and moves the head-piece 23 behind the cam 36 so that the bolt is held in the semiretracted position, the initial movement of the handle takes up the lost motion between the draw bar 25 and the bolt and thus frees the dead bolt cross-bar which is thus retracted by engagement with the keeper. The handle sleeve 48 contains a pair of members 55, 60 with sloping cam faces, one 55 attached to the sleeve 48 and the other 60 to the escutcheon plate 61; the member 55 is loaded by the spring 53 and the arrangement allows the handle 17 to return to a predetermined position when the door is closed and also permits counter clockwise rotation in this position. The spindle 11 is detachably connected to the pinion 10 by a pin 14 engaging slots 13 in a sleeve 8 secured to the pinion. On the opposite side of the door to the handle 17, is a handle 15 containing a barrel lock mechanism connected to the spindle 11 by a universal joint 16.