Patent GB-829326-A (GB)
Title: Locking handles for rotary switches
Inventor: MORGAN EDWARD ALBERT
IPC: E05B13/10
Filed: 1957-04-06
Abstract: 829,326. Keylocks. ALLOY PRESSURE DIE PRODUCTS Ltd. March, 26, 1958 [April 6, 1957], No. 11291/57. Class 44 In a locking handle for a rotary switch of the kind in which the boss or shank 11 of the handle incorporates a key operated cylinder lock for throwing a bolt 22 whereby the handle and the switch spindle 16 which it actuates can be locked in different predetermined angular positions in a fixed barrel or sleeve 12 within which the handle boss or shank is mounted for rotation, the thrower or bolt actuating member 18 instead of being fixed to the plug 19 of the cylinder lock is operated by the plug through an intermediate member 20 which is mounted for rotation in the same bore as the plug and has abutments which co-operate with confronting abutments on the plug and the thrower or bolt actuating member respectively. With this construction by using different intermediate members the key can either be withdrawn when the bolt is in its locked or unlocked positions or alternatively it can only be withdrawn when the bolt is in the unlocked position. The sleeve or barrel 12 is provided with an annular series of bolt holes 13 which are spaced to agree with the various operative positions of the rotary switch and a pointer 14 on the shank or boss 11 works in conjunction with a scale on the forward end of the sleeve or barrel 12 or on a front panel 15 in which the sleeve or barrel 12 is mounted, to indicate the switch positions. To enable the key to be withdrawn in both the locked and the unlocked positions of the bolt a 180 degrees lost motion connection is provided between the plug 19 of the cylinder lock and the intermediate member 20 and this is achieved by providing the plug 19 with an abutment in the form of a stud 25, the co-operating abutment on the intermediate member being a face 26 on its adjacent end which is distanced from the axis of the intermediate member by an amount corresponding to the radius of the stud. A positive driving connection is provided between the intermediate member and the thrower or bolt actuating member 18, the abutment on the intermediate member being an eccentrically positioned stud 27 while the abutment on the thrower or bolt actuating member 18 is a transverse slot or groove 28. The thrower or bolt actuating member 18 is bifurcated to straddle a necked portion of the bolt 22 and the arrangement is such that 180 degrees movement of the intermediate member is converted into longitudinal movement of the bolt; the 180 degrees lost motion connection between the plug 19 and the intermediate member means that the plug must be turned through 360 degrees to move the bolt from its locked to unlocked positions and vice versa. When it is desired that the key cannot be withdrawn the 180 degrees lost motion connection is replaced by a positive driving connection, the stud 25 on the plug 19 then engaging a hole in the intermediate member instead of an abutment face. A spring loaded ball catch 29 co-operates with holes 30 in the sleeve or barrel 12 to retain the intermediate member in its various positions.