GB145527A - Improvements relating to electric starting devices for internal combustion engines - Google Patents

Abstract

145,527. Bosch Akt-Ges., R. May 26, 1919, [Convention date]. Turning-gear.-In an electric starter in which a free-wheel coupling between the starter and the engine shaft is brought into engagement by a brake device and in which a weak current is supplied initially to the starting-motor, the supply of full current to the motor is not effected until the play m the driving-gear is taken up. In the form shown in Figs. 1 and 2, current is supplied initially through a high-resistance field winding H on closing a switch d. The motor M is geared to the engine shaft w through planetary gearing P, a chain-wheel z on the shaft of the planet carrier o, and a chain k passing over a chainwheel F having a free-wheel connexion with the engine shaft. The free-wheel comprises a ring v carrying a pawl x engaging a notch in the chain wheel and normally held by a spring y out of engagement with a toothed disk u on the shaft w. When the switch d is closed, a brake band c, connected by a spring f to a solenoid core r, is applied to the ring v, and the pawl x is thus brought into engagement with the disk u. The consequent tightening of the chain k actuates a lever h and so withdraws a catch g from the end of the core r, which then closes a switch i, completing the circuit of the main field coil E. In a modification, the lever h is acted upon by a lug on the outer member p' of the planetary gearing, which is allowed a limited angular movement against a spring. In another form, a lever such as h moves a solenoid core within the solenoid coil, the switching movement being completed by the attraction of the coil. This core is separate from the one actuating the brake. In other forms, the main switch is closed by axial movement of the motor armature, and the delay in the action of the switch may be caused by a pneumatic, hydraulic, or electric damping-device.