Patent ID: 8402953

Claim:
An engine comprising: an engine base having a plurality of cylinders and a supercharger; an engine rotation speed detection means; a supercharger rotation speed detection means that detects rotation of the supercharger as a pulse; an operation means that divides the pulse by a dividing ratio and calculates it as a divided pulse; and a control means that judges a surge state of the supercharger, wherein the control means: sets a predetermined position of a piston of each of the cylinders in a crank angle of the engine as count start timing of the divided pulses, outputs the divided pulse, which is operated based on a time for counting the divided pulse a predetermined number of times from the count start timing of the divided pulse and the predetermined number of times, as a first output, and judges that, if a difference between the first outputs of every cylinder is not less than a predetermined value, the supercharger is in the surge state.