| 摘要 |
<p>An improvement is provided in a combination of an axial split-pin tumbler-type lock mechanism and a key therefor, wherein the mechanism includes a lock cylinder and an operating part rotatable therein, the operating part including a cylindrical head and a key guide post having a reduced diameter with respect to the head, the head having tumbler bores extending therethrough and disposed radially outwardly of the post, and wherein the key includes a shank having a socket adapted for receiving the post therein, and bittings on the outer periphery of the shank adapted for endwise engagement with tumblers carried by the bores to free the operating part for rotation, such improvement including means providing a longitudinal blind drive groove in the post and facing one of the tumbler bores substantially in a longitudinal plane therewith, and a drive lug on the shank extending radially inwardly from the wall of the socket and substantially in a longitudinal plane with one of the bittings and adjacent thereto, the lug being adapted to be received in the groove for interengaging the key and the operating part to cause the latter to rotate when the key is turned, the aforesaid one bitting being adapted to engage a tumbler carried by the aforesaid one bore. An additional improvement is the provision of a drive groove having a maximum depth of about 0.030 inch.</p> |
