US 2006/0218901 A1 · Diagnosis apparatus for secondary air supply apparatus

Abstract

A secondary air supply system includes a supply passage, a valve, and a detecting unit. Secondary air is supplied to the upstream of a purification apparatus in an exhaust passage of an engine through the supply passage. The valve communicates and blocks the supply passage to be in open and close conditions. The detecting unit detects a detection object of secondary air in the upstream of the valve in the supply passage. A diagnosis apparatus for the secondary air supply system includes a diagnosis unit that obtains a detection result of the detecting unit in each of the open and close conditions of the valve for evaluating an abnormity of the secondary air supply system in accordance with the detection result. The diagnosis apparatus includes a reliability maintaining unit that determines the diagnosis operation of the diagnosis unit to be valid when the detecting operations in the open and close conditions are continuously performed.

Claims32

Dependent claims

A diagnosis apparatus for a secondary air supply system for an internal combustion engine having at least one exhaust passage, which connects with an exhaust gas purification apparatus, the secondary air supply system comprising:

at least one secondary air supply passage, through which secondary air is supplied to an upstream of an exhaust gas purification apparatus in at least one exhaust passage of the internal combustion engine;
at least one valve for communicating the secondary air supply passage to be in an open condition and for blocking the secondary air supply passage to be in a close condition;
and
a detecting unit for detecting a detection object of secondary air in an upstream of the valve in the secondary air supply passage,
the diagnosis apparatus comprising:
a diagnosis unit for obtaining a detection result of the detecting unit in each of the open condition of the least one valve and the close condition of the least one valve, the diagnosis unit being adapted to evaluating an abnormity of the secondary air supply system in accordance with the detection result;
and
a reliability maintaining unit for determining the diagnosis operation of the diagnosis unit to be valid when the detecting operation of the detecting unit in the open condition and the detecting operation of the detecting unit in the close condition are continuously performed.

5 more elements

A diagnosis apparatus for a secondary air supply system for an internal combustion engine having an exhaust passage, which connects with an exhaust gas purification apparatus, the secondary air supply system comprising:

a secondary air supply passage that connects with the exhaust passage;
an air pump for supplying secondary air to an upstream of the exhaust gas purification apparatus in the exhaust passage of the internal combustion engine through the secondary air supply passage;
and
a detecting unit for detecting a detection object of secondary air,
the diagnosis apparatus comprising:
a diagnosis unit for performing a diagnosis operation to evaluate an abnormity of the secondary air supply system in accordance with a detection result of the detecting unit;
an obtaining unit for obtaining information of temperature of the air pump;
and
a changing unit for changing the diagnosis operation of the diagnosis unit in accordance with the information of the temperature of the air pump.

6 more elements

Dependencies are inferred from the claim text.

Diagnosis apparatus for secondary air supply apparatus

Life of this patent

Diagnosis apparatus for secondary air supply apparatus

Life of this patent

Abstract

Claims32