Patent GB-1314176-A (GB)
Title: Vehicle steering column locking mechanisms
IPC: B60R25/021
Filed: 1969-09-06
Abstract: 1314176 Anti-theft devices C E MARSHALL (WOLVERHAMPTON) Ltd 18 Sept 1970 [6 Sept 1969] 44178/69 Heading B7J [Also in Division E2] A combined steering column locking mechanism and ignition switch means 10 for a motor vehicle has a body 11, bolt 14 housed within the body 11 and movable relative thereto between a projecting position in which it engages a column (not shown) and a retracted position in which it is clear of the column, and has key-operated means within the body 11 for moving the bolt 14 and for actuating the motor vehicle ignition system (not shown). If a key (not shown) has been inserted into a lock 35, it can only be removed when the ignition system is de-actuated, the bolt 14 moving into its projecting position when the key is removed. A spring 53 which is secured to the bolt 14 connects the latter electrically to a strip 51 when the bolt 14 is in its retracted position. Electricity is then connected with a warning device and with an electrical switch (not shown), the latter being closed when the door of the vehicle is either opened or closed. The body 11 has a portion 12 which is clamped around a steering column and has a bore 13 which receives the bolt 14 therein. The bolt 14 is provided with a blind axial bore 16 and with a radial bore 18, a spring 15 being located between a spindle 17 mounted in the bore 18 and an end of the bore 16. The spindle 17 extends through radial bores 19, 20 formed in the body 11, and is non-rotatably connected to a cam 21 which is prevented from moving axially by means of a circlip 22. A portion 25 of the bolt 14 is attached to a shoe 24, the shoe having a cam surface 26 engageable with a portion 8 of the cam 21, and the shoe having a recess 27 in its side 28 with a pawl 29 therein. Outward movement of the pawl 29 is limited by a projection 31 thereon abutting a stop 32 which is formed at the end of a ledge 33. A cylinder lock 35, housed in a bore 34 of the body 11, has a barrel 36 which receives the key and has an escutcheon 37 which is secured to the body 11. In operation, prior to the insertion of the key into the barrel 16, a key-receiving plate 39 is flush with a flange 40 of the escutcheon 37, a peg 47 which is secured to an extension 43 of the barrel 36 is displaced to the right of the position in which it is shown in Fig. 1 and an abutment member 45 is clear of a cavity 23. The bolt 14 is in its projected position, the cam surface 26 of the shoe 24 is in contact with the portion 8 of the cam 21 and the pawl 29 in the same plane as the abutment member 45. When the key is inserted into the barrel 36 and is pushed axially, the barrel is moved so that tumblers 38 of the barrel align with a flange 41 of the escutcheon 37 and the abutment member 45 pushes the pawl 29 into the recess 27 against the action of a spring 30. When the key is rotated the cam 21 moves the shoes 24 to cause the bolt 14 to be retracted against the action of the spring 15 so that it is disengaged from the steering column. The bolt shoe 24 moves axially, the abutment member 45 disengages from the pawl 29 which then returns to the position shown in Fig. 3 under the action of a spring 30, Fig. 4. The pawl 29 now engages the lower surface of the abutment member 45, Fig. 1, so that the bolt 14 is retained in its retracted position.