Patent GB-819911-A (GB)
Title: Improvements relating to door locks or latches
IPC: E05B65/20
Filed: 1955-11-23
Abstract: 819,911. Latches. THORNE, H. O.ct. 8, 1956 [Nov. 23, 1955], No. 33538/55. Class 44. A vehicle door lock or latch comprises locking or latching means adapted to be actuated by manually operable means from the interior and exterior of the vehicle, "child safety" dead-locking means operable to lock the locking means from the interior of the vehicle, and releasable only by the manually operable means from the exterior of the vehicle, and means whereby release of the deadlocking means is automatically effected by impact of the vehicle. In the arrangement according to Figs. 1 and 2 as applied to a door lock having an outer fixed handle with a press button, an inner lever handle and a sill-button lock, a rotary bolt member 2 is retained in locking position by an arm 1 of a bell-crank lever the other arm 4 of which co-operates with a stop 4a. The bell-crank lever co-operates through a pin and a slot connection 3, 8 with a lever 6, 7 which is operable by an outside press button 6a to release the bold when the lever is not dead-locked by anti-clockwise rotation of a locking lever 10, 11 by an internal sill button 12. A release lever 16, 17 pivoted about a pin 15 and engaging the arm 11 of the locking lever 10, 11 is adapted to be engaged at its end 18 by a projection 19 on an arm 20 of an inner handle bell-crank lever 20, 22 whereby upon normal operation of the inner handle the lever 10, 11 is moved to its release position. The arm 22 of the lever 20, 22 underlies the arm 4 of the lever 1, 4 whereby actuation of the inner handle moves the arm 1 to its release position without movement of the lever 6, 7. A " child safety" arm 23 is pivotally mounted on a sleeve 26 on the lock casing 25 and is located on the sleeve by a spring 27..The arrangement is such that when the inner handle is moved from its normal position in a reverse direction to turn the lever 20, 22 anti-clockwise a pin 32 on the lever 20, 22 engages a shoulder 31 on the arm 23 as the latter is rotated, by engagement of projection 19 with a spur 34. The arm 23 is released by operation of the push button 6a which causes the arm 4 to rise and engage a spur 33 whereby to swing the arm 23 and free the pin 32. The arm 23 is also automatically releasable under impact securing in either direction of swing and by reason of the mounting 26, 27, in a direction normal thereto. In a modification, Fig. 5 (not shown) the safety arm is provided with a triangular projection which normally lies below the projection 32 on arm 22 but which when the inner handle is moved to the safety posi-. tion, lies above the ;projection 32. The safety arms is maintained in a central position by a light leaf spring. The inner handle, Fig. 6 (not shown) may be connected in known manner for remote control. In another arrangement, Figs. 7 and 8 in which the outer handle is of the pivoted-lever type, the handle actuates a pin which engages. a slot. 51 on a slidable plate 52, a projection 53 on which engages an arm 54 of a pivoted locking plate 55. An arm 59 of plate 55 is located above an arm 63 of a release lever 61 which is connected through a link. 60 to an inner handler A dead-locking plate 65 is operable by a sill button to dead-lock the inner and outer handles. A " child safety " lever 72 is pivotally mounted on the pivotal axis 65a of the plate 65 and is provided with a notch 73 adapted to engage a pin 64 on an arm 63 of lever 61 when the inner handle is moved in the reverse direction to normal. The lever 72 is released by operation of the outer handle to cause arm 59 to move along a cam surface 75 on the lever 72. The lever 72 which may be weighted, is arranged for automatic release under impact. In another arrangement Figs. 10 to 12 (not shown) in which a sliding latch-bolt is operable by inner and outer lever handles and in which a pin on a slider operable by the inner handle engages a groove in a bell-cranked lever operable by the outer handle to lock the outer handle, and in whichthe latter is released by returning the inner handle to its normal position, a "child safety" catch is pivotally mounted on a vertical axis and is provided with a detent which is adapted to engage a part of the slider when the inner handle is moved reversely beyond the normal locking position. Release of the catch is effected by operation of the outer handle or by impact. In some cases the " child safety device " may be moved to its operative position by a sill button. Reference has been directed by the Comptroller to Specification 791,080.