US 6,546,789 B1Granted

Method and arrangement for monitoring the operation of an intake-manifold flap for switching over the intake manifold of an internal combustion engine

AssigneeRobert Bosch GmbH

InventorErnst Wild

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Abstract

The invention is directed to a method for monitoring the operation of an intake-manifold flap for switching the intake manifold of an internal combustion engine. The engine rpm (nmot) is measured utilizing an rpm sensor and the air mass flow (ms) is measured utilizing an air mass flow sensor. The intake manifold pressure (ps) is computed on the basis of the engine rpm (nmot) and the air mass flow (ms) for at least two different intake-manifold flap positions and, simultaneously, the intake-manifold pressure is measured utilizing a pressure-detecting sensor. The difference between the computed and measured intake-manifold pressures is formed for each one of at least two positions of the manifold flap. A diagnosis is then made of the operation of the intake-manifold flap by evaluating the differences formed.

Claims7

Dependent claims

A method for monitoring the operation of an intake-manifold flap of an intake manifold of an internal combustion engine, the intake manifold accommodating said intake-manifold flap therein and being provided to conduct an air mass flow (ms) to the cylinders of said engine and being arranged between an air intake pipe holding a throttle flap and the inlet valves of said cylinders, wherein a change of intake manifold flap position changes the resonance characteristics of the intake manifold to achieve optimal low speed torque and high rated output at maximum engine speed and the engine having an engine rpm (nmot) when running, the method comprising the steps of:

measuring the engine rpm (nmot) utilizing an rpm sensor;
measuring the air mass flow (ms) utilizing an air mass flow sensor;
computing the intake manifold pressure (ps) based on said engine rpm (nmot) and said air mass flow (ms) for at least two different intake-manifold flap positions corresponding to respectively different geometries of said intake manifold and respectively different ones of said resonance characteristics and, simultaneously, measuring said intake-manifold pressure utilizing pressure-detecting means;
forming a difference between the computed and measured intake-manifold pressures for each one of said at least two different positions of said intake-manifold flap;
and,
making a diagnosis of the operation of said intake-manifold flap by evaluating the differences formed.

3 more elements

(a) setting said intake-manifold flap to a first position corresponding to a first one of said resonance characteristics;
(b) measuring the engine rpm (nmot) utilizing an rpm sensor;
(c) measuring the air mass flow (ms) utilizing an air mass flow sensor;
(d) computing the intake-manifold pressure (ps) based on said engine rpm (nmot) and said air mass flow (ms) corresponding to said first position of said intake-manifold flap;
(e) measuring the intake-manifold pressure (ps) utilizing a pressure sensor;
(f) forming and storing the difference of the computed and measured intake-manifold pressures to form a first pressure difference corresponding to said first position of said intake-manifold flap;
(g) setting said intake-manifold flap to a second position corresponding to a second one of said resonance characteristics different from said first one of (said resonance characteristics;
(h) repeating steps (b) to (f) to obtain a stored second pressure difference corresponding to said second position of said intake-manifold flap;
(i) subtracting the first and second pressure differences from each other to determine a difference quantity;
and,
(j) evaluating said difference quantity to make a diagnosis of the operation of said intake-manifold flap.

8 more elements

Dependencies are inferred from the claim text.

Facts

Application: 09/708,539Filed 9 Nov 2000 · continuation in part
Priority: DE 197 27 66930 Jun 1997
Granted: 15 Apr 2003
Term ends: Not estimatedThe source records don’t support an estimate.

Classification9 codes

F02B 27/02
Use of kinetic or wave energy of charge in induction systems, or of combustion residues in exhaust systems, for improving quantity of charge or…:…
F02B 27/0221
Oscillating pipe charging, i.e. variable intake pipe length charging: resonance charging combined with oscillating pipe charging
F02B 27/0278
Valves: multi-way valves
F02B 27/0294
The systems having variable, i.e. adjustable, cross-sectional areas, chambers of variable volume, or like variable means: actuators or controllers…