Patent GB-1296852-A (GB)
IPC: E05B67/24
Filed: 1969-01-24
Abstract: 1296852 Locks INGERSOLL LOCKS Ltd 21 Jan 1970 [24 Jan 1969] 4300/69 Heading E2A A key operated plug assembly for a locking mechanism adapted to be pivotally mounted in a lock body 11 comprises an intermediate portion, including body engaging means to prevent said pivotal movement of the plug assembly within the body, said body engaging means being rendered inoperative by the insertion into the plug assembly of an appropriate key, a face element 33 having therein a key receiving opening and being connected to the remainder of the plug assembly by means of a rupturable connection, the arrangement being such that when more than a predetermined force is applied to the face element the collapsible connection fails so that the face element rotates relative to the remainder of the plug assembly. In the construction shown The plug assembly in addition to the intermediate portion 32 and the face element 33 has a cam means 31 for positively locating locking balls 20 in engagement with recesses 21 in the limbs of the shackle to prevent release of the shackle from the body; the cam means 31 includes a pair of camming faces 41 which when located adjacent the balls permit the balls to move out of the recesses in the shackle limbs to free the shackle. Rotation of the plug assembly through 90‹ from such position causes the cam means to engage the balls and urge them into the recesses. The intermediate portion is disposed between the cam means and the face element and includes a pair of spaced rods 45, 46 which extend from the cam means to engage the face the plug assembly 30 is part of a padlock, the body 11 being the body of the padlock and the padlock also including a shackle 17 having two limbs 16 which are received in bores 15 in the body. The body 11 is made up of a number of plates 12 secured together and in addition to the bores 15 it has a main bore 13 which extends from an end phase of the body in which the plug assembly is disposed. element 33 by means of the rupturable connection; as shown the rupturable connection is provided by chamfering the end portion of each rod and providing the face element with shallow recesses 48, the chamfering permitting the rods to become disengaged from the face element when more than the predetermined force is applied; instead of being chamfered however the end portions of the rods can be rounded or can be of reduced cross section so that the end portions shear when the excessive force is applied to the face element. The portion 32 also includes a casting carried by the rods the casting including spacers 51 and dividers 50, the spacers and dividers being arranged alternately and the spaces between them containing ten levers arranged in pairs the two levers of each pair being separated by one of the dividers; the two levers 60 of each pair are pivoted in a scissor configuration about the rod 45 and each lever is spring biassed by means of a spring 61 to a datum position and has a key engaging portion 62 which together with the corresponding portions of the other levers defines a central key way within the centre of the plug assembly, the key when inserted moving the levers against their spring loadings to operative positions. Each lever has a notch 66 in its peripheral edge and when the levers are in their operative positions with the correct key inserted the notches 66 are all aligned to define a longitudinal groove 67 parallel to the axis of the plug assembly and to the axis of the second rod 46 which constitutes a pivot for the body engaging means which is in the form of a talon 70 which has a pair of space arcuate arms 71 terminating in a thickened portion 72 with a longitudinal ridge 73 which when the key is inserted into the key way is able to enter the groove 67 defined by the notches 66 when the plug assembly is rotated by the key, this causing the internal wall of the main bore of the padlock body to urge the talon 70 inwardly, which is allowed by the groove. A part of the talon is normally disposed within a longitudinal recess 14 formed in a wall of the main bore 13 and so prevents rotation of the plug assembly in the bore. The talon is held in the recess 14 by a wire spring 88 carried by the cam means 31 across the entrance to a recess 81 and the talon 70 has a pin 74 which engages the spring; rotation of the plug assembly by the key causes the pin to bear against the spring and move it inwardly.