Method of controlling a starter system for a heat engine, of the type having two starters, and apparatus for performing the method

A method of controlling a starting system for a heat engine, in a combination comprising the said heat engine, the said starting system coupled to the engine, and an ignition system having an ignition key, the heat engine including a rotatable starter crown, the ignition system comprising a first starter and a second starter, both connected electrically with the ignition system for activation by operation of the said key, each said first and second starters comprising, respectively:

• a first and a second electric starter motor;
• a rotatable first and second pinion driven by the corresponding said motor;
• and a first and a second power circuit, including in combination the corresponding said motor, a first and a second power interrupter, respectively, and a first and a second control coil, respectively, for actuating the corresponding said interrupter,
• wherein the said method includes the steps of:
• operating the ignition key to enable each said control coil to be energised whereby to close the corresponding power interrupter to start the associated motor;
• when each motor has started, engaging, by running of that motor, the pinion thereof with the starter crown, whereby both pinions engage the starter crown in parallel with each other so as to start the engine,
• retarding the closing of said second power interrupter with respect to the first by a time delay selected so as to prevent a voltage drop caused by closure of the first power interrupter causing reopening of the second interrupter.