Patent GB-1023454-A (GB)
Title: Improvements in or relating to releasable fastening devices
Inventor: HEMUS ROBERT BAYNHAM
IPC: E05B65/19
Filed: 1961-09-11
Abstract: 1,023,454. Latch fastenings. WILMOTBREEDEN Ltd. Sept. 11, 1962 [Sept. 11, 1961], No. 32493/61. Heading E2A. A releasable fastening device has a rotary bolt 5 mounted for angular movement between an unlatched position and a latching position to which it is urged by spring means 33 for latching engagement behind a latching surface of a keeper 6, the keeper and bolt undergoing relative translatory movement during fastening in a direction generally aligned with the rotational axis of the bolt, latch retaining means 15 which are moved during the translatory movement from a retaining position in which the bolt is held in the unlatched position in which it can enter freely into the keeper to a released position in which the bolt is freed for movement to the latching position in which it cannot be withdrawn from the keeper and release means 25 arranged to turn the bolt from the latching position for withdrawal from the keeper. In the construction shown the device is intended for fastening the boot lid 4 of a motor vehicle and the bolt 5 has a cylindrical body with a cross pin 9 adjacent its lower end the pin 9 providing two diametrically opposed latching projections. The bolt 5 is rotatable between the unlatched and latching positions in a housing 1 which is fixed by screws to the bottom edge of the boot lid 4. The keeper 6 is fixed to the vehicle body by screws and it has an aperture 10 through which the bolt 5 including the pin 9 passes during the translatory movement. Turning of the bolt 5 to the latching position moves the cross pin 9 behind the keeper 6 so that it engages the rear surface of the keeper. The housing 1 has two guide pins, not shown, parallel with the bolt and which project further than the bolt 5 and have tapered nose sections and these pins enter guide bores in the keeper 6 during the translatory movement. The retaining means 15 is a slide which is mounted alongside the bolt 5 in the housing 1 and at its upper end it has a laterally projecting arm 16 which extends diametrically across the upper end of the bolt 5 the arm being pulled into a cross slot 17 in the bolt by a tension spring 18 when the bolt is turned to the unlatched position; hence in this position the bolt is retained by the retaining means. When the boot lid is open the projecting end of the bolt is concealed by a shroud 19 which is slidably mounted on the guide pins and which is urged to its shrouding position by springs around the guide pins; the shroud has grooves which receive the cross pin 9 of the bolt and the length of the grooves limits the downward movement of the shroud 19. The slide 15 has a forked lower end and the fork arms 24 project slightly from the housing 1 and in the fastened position a slight clearance exists between the ends of these arms and the inner face of the shroud 19. Closing the lid causes the shroud 19 to come into contact with the keeper and so move it up the pins to unshroud the bolt and overtravel of the lid against the resilience of lid seal 34 causes the arms 24 to come into contact with the shroud and this moves the slide 15 sufficiently to move the arm 16 out of the cross slot 17 in the bolt and the bolt then rotates to the latching position under the urge of the spring 33 to fasten the lid to the vehicle body. The release means 25 comprises a contactor pivotally mounted on the housing 1 one arm 26 being engaged by an externally mounted push button 27 and the other arm 28 having a slot which engages a cross pin 30 at the upper end of the bolt 5. Hence depression of the push button 27 pivots the contactor 25 which in turn rotates the bolt from the latching position to the unlatching position and the springs 23 urge the shroud against the vehicle body to cause the boot lid to spring open.