Method engine starting device and starting the engine

PROBLEM TO BE SOLVED: To provide an engine starting device capable of increasing a starting responsibility of an engine.SOLUTION: A belt 4 for transmitting a driving force is wound around a crank shaft 9 of an engine 2 and a motor generator 3. A chain 6 is wound around a valve timing adjustment mechanism 7 arranged at cam shafts 16, 17 for opening or closing to drive either an intake valve or exhaust valve of the engine 2 and the crank shaft 9. An engine starting device 1 applies a normal rotation torque to the crank shaft 9 under a delayed angle driving of the valve timing adjustment mechanism 7 and after a reverse rotation torque is generated at the motor generator 3, the engine starting device 1 restricts an extension or retraction of a first arm 51 of an automatic tensioner 5, produces a normal rotation torque to the motor generator 3 to start the engine 2. With this arrangement, it is possible to increase the reverse rotation torque of the motor generator 3, increase a tension of the belt 4 and restrict a slipping of the belt 4 when the engine 4 is started.