	US 7,500,363 B2
	Failure detecting device for supercharging-pressure control means in supercharging device of engine
Hirofumi Hara, Saitama (Japan); Atsuhiro Miyauchi, Saitama (Japan); Kazuhiko Imamura, Saitama (Japan); Takashi Kon, Saitama (Japan); and Yoshinori Andou, Saitama (Japan)
Assigned to Honda Motor Co., Ltd., Tokyo (Japan)
Filed on Jul. 25, 2007, as Appl. No. 11/878,604.
Claims priority of application No. 2006-201609 (JP), filed on Jul. 25, 2006.
Prior Publication US 2008/0022679 A1, Jan. 31, 2008
Int. Cl. F02B 33/00 (2006.01)

U.S. Cl. 60—611 [60/602; 123/561]

10 Claims

1. A failure detecting device for supercharging-pressure control means in a supercharging device of an engine, the supercharging device comprising:

a turbocharger for supercharging the engine;

supercharging-pressure control means for controlling a supercharging pressure in a supercharging intake air passage downstream of the turbocharger;

engine-load detecting means for detecting an engine load; and

supercharging-pressure detecting means for detecting the supercharging pressure in the supercharging intake air passage,

wherein the failure detecting device comprises:

acceleration-state determining means for determining whether a turbine is in an acceleration state on the basis of the engine load detected by the engine-load detecting means;

supercharging-pressure-control-state determining means for determining whether the supercharging-pressure control means is in a maximum supercharging pressure control state for maximizing the supercharging pressure in the supercharging intake air passage;

failure-detection permitting means for permitting failure detection for the supercharging-pressure control means, when the engine-load detecting means detects an engine load equal to or larger than a predetermined value, the acceleration-state determining means determines that the turbine is in the acceleration state, and the supercharging-pressure-control-state determining means determines that the supercharging-pressure control means is in the maximum supercharging pressure control state;

convergent-value calculating means for calculating a convergent value of the supercharging pressure on the basis of the engine load detected by the engine-load detecting means, when the failure-detection permitting means permits the failure detection;

delay-coefficient calculating means for calculating a delay coefficient of the turbocharger on the basis of the supercharging pressure detected by the supercharging-pressure detecting means and the convergent value of the supercharging pressure calculated by the convergent-value calculating means; and

failure determining means for determining whether a failure of the supercharging-pressure control means has occurred on the basis of the delay coefficient calculated by the delay-coefficient calculating means.