GB646670A - Improvements relating to electric starting motors for internal combustion engines - Google Patents

Abstract

646,670. Turning-gear. C. A. V., Ltd. Oct. 25, 1948, No. 27659. '[Class 7(v)] [Also in Group XXXVII] In electric starters of the kind in which a pinion d is slidable by an electromagnet into engagement with a gear wheel on the engine to be started and in which a switch, which may be comprised of contacts h, m, operable by the electromagnet is closed for supplying current to the starter after the pinion d has moved into engagement with the engine there is provided spring means i for imparting closing movement to the switch, the spring means being adapted to be energized by movement of the movable part, such as core a, of the electromagnet. When the electromagnet winding b is energized a hollow iron armature g, which is freely mounted on the plunger f of core a is magnetically held in contact with the end of the winding enclosure e by the flux generated by the winding b. During the first part of the movement of plunger f, a collar k secured thereto, advances into contact with an abutment j slidable relatively to plunger f and armature g. Continued movement of the plunger f causes the collar k to move abutment j into contact with the end face of a hollow part p, secured to the armature g, against the action of the spring i located between the other end of part p and the abutment j. After the pinion d has meshed with the engine the spring i causes the armature g to be separated from the enclosure e and contact h on the armature g to complete a circuit through fixed contacts m to turn the starter. During the return of the core a a spring n returns the armature and contact h to their initial positions. In a modification, the moving contact is operated through a toggle mechanism and an over-centre spring, the core plunger serving to compress the spring.