Method and functional monitoring apparatus for functional monitoring of an apparatus for variable setting of a cylinder compression in a reciprocating-piston internal combustion engine

Patent metadata

Field	Value
Publication number	US-10408138-B2
Application number	US-201615287955-A
Country	US
Kind code	B2
Filing date	Oct 7, 2016
Priority date	Oct 12, 2015
Publication date	Sep 10, 2019
Grant date	Sep 10, 2019

Abstract

A method for functional monitoring of an apparatus for variable setting of a cylinder compression in a reciprocating-piston internal combustion engine is described, including ascertaining a value of an engine parameter which is indicative of an engine position of the internal combustion engine at a defined cylinder compression; comparing the ascertained value with a further value of the engine parameter; and determining, depending on a result of the comparison, whether the apparatus for variable setting of the cylinder compression is functioning correctly.

First claim

What is claimed is:

1. A method for functional monitoring of an apparatus for variable setting of a cylinder compression in a reciprocating-piston internal combustion engine, comprising:
detecting, using a crankshaft position sensor and a crankshaft position encoder wheel situated on a crankshaft of the internal combustion engine, first positions of the crankshaft over time at a first defined cylinder compression;
comparing, by a computer processor of a functional monitoring apparatus, a course of the detected first positions of the crankshaft over time to (i) a modeled course of crankshaft positions over time for the defined cylinder compression, or (ii) a course detected second positions of the crankshaft over time at a second defined cylinder compression, different than the first defined cylinder compression, the detected second position being detected using the crankshaft position sensor and the crankshaft position encoder; and
determining, depending on a result of the comparison, by the computer processor, whether the apparatus for variable setting of the cylinder compression is functioning correctly.

2. The method as recited in claim 1 , wherein in the detecting step, the first positions of the crankshaft over time are detected in an engine start phase or an engine stop phase, the internal combustion engine being operated in that context with an open drive train or in a coasting mode.

3. The method as recited in claim 1 , wherein in the comparing step, the course of the detected first positions of the crankshaft over time is compared to the modeled course of crankshaft positions over time for the defined cylinder compression, and wherein in the determining step: (i) a determination is made that the apparatus is functioning correctly when a difference between the course of the detected first positions of the crankshaft over time and the modeled course of crankshaft positions over time for the defined cylinder compression is less than or equal to a predetermined threshold value, or (ii) a determination is made that the apparatus is incorrectly when the difference between the course of the detected first positions of the crankshaft over time and the modeled course of crankshaft positions over time for the defined cylinder compression is greater than a predetermined threshold value.

4. The method as recited in claim 1 , wherein in the comparing step, the course of the detected first positions of the crankshaft over time is compared to the course of the detected second positions of the crankshaft over time at the second defined cylinder compression, and wherein in the determining step: (i) a determination is made that the apparatus is functioning incorrectly when a difference between the course of the detected first positions of the crankshaft over time and the course of the detected second positions of the crankshaft over time at the second defined cylinder compression is less than or equal to a predetermined threshold value, or (ii) a determination is made that the apparatus is correctly when the difference between the course of the detected first positions of the crankshaft over time and the course of the detected second positions of the crankshaft over time at the second defined cylinder compression is greater than or equal to a predetermined threshold value.

5. A method for functional monitoring of an apparatus for variable setting of a cylinder compression in a reciprocating-piston internal combustion engine, comprising:
detecting, using a crankshaft position sensor and a crankshaft position encoder wheel situated on a crankshaft of the internal combustion engine, first positions of the crankshaft over time at a first defined cylinder compression;
determining, by a computer processor of a functional monitoring apparatus, a first time duration of a predetermined number of crankshaft revolutions based on the first determined positions;
detecting, using the crankshaft position sensor and the crankshaft position encoder wheel situated on a crankshaft of the internal combustion engine, second positions of the crankshaft over time at a second defined cylinder compression different than the first define cylinder compression;
determining, by the computer processor, a second time duration of the predetermined number of crankshaft revolutions based on the second determined positions;
comparing, by the computer processor, the first time duration and the second time duration; and
determining, depending on a result of the comparison, by the computer processor, whether the apparatus for variable setting of the cylinder compression is functioning correctly.

6. A functional monitoring apparatus for functional monitoring of an apparatus for variable setting of a cylinder compression in a reciprocating-piston internal combustion engine, wherein the apparatus is configured to:
detect, using a crankshaft position sensor and a crankshaft position encoder wheel situated on a crankshaft of the internal combustion engine, first positions of the crankshaft over time at a first defined cylinder compression;
compare, by a computer processor of the apparatus, a course of the detected first positions of the crankshaft over time to (i) a modeled course of crankshaft positions over time for the defined cylinder compression, or (ii) a course detected second positions of the crankshaft over time at a second defined cylinder compression, different than the first defined cylinder compression, the detected second position being detected using the crankshaft position sensor and the crankshaft position encoder; and
determine, depending on a result of the comparison, by the computer processor, whether the apparatus for variable setting of the cylinder compression is functioning correctly.

7. The functional monitoring apparatus as recited in claim 6 , wherein in the comparing, the course of the detected first positions of the crankshaft over time is compared to the modeled course of crankshaft positions over time for the defined cylinder compression, and wherein in the determination: (i) a determination is made that the apparatus is functioning correctly when a difference between the course of the detected first positions of the crankshaft over time and the modeled course of crankshaft positions over time for the defined cylinder compression is less than or equal to a predetermined threshold value, or (ii) a determination is made that the apparatus is incorrectly when the difference between the course of the detected first positions of the crankshaft over time and the modeled course of crankshaft positions over time for the defined cylinder compression is greater than a predetermined threshold value.

8. The functional monitoring apparatus as recited in claim 6 , wherein in the comparing, the course of the detected first positions of the crankshaft over time is compared to the course of the detected second positions of the crankshaft over time at the second defined cylinder compression by the apparatus, and wherein in the determination: (i) a determination is made by the computer processor that the apparatus is functioning incorrectly when a difference between the course of the detected first positions of the crankshaft over time and the course of the detected second positions of the crankshaft over time at the second defined cylinder compression is less than or equal to a predetermined threshold value, or (ii) a determination is made by the computer processor that the apparatus is correctly when the difference between the course of the detected first positions of the crankshaft over time and the course of the detected second positions of the crankshaft over time at the second defined cylinder compression is greater than or equal to a predetermined threshold value.

Assignees

• Bosch Gmbh Robert

Inventors

• Gladel Pascal
• Kesch Bernd
• Jessen Holger

Classifications

• Y02T10/40

  Engine management systems · CPC title

• F02D41/009

  using means for generating position or synchronisation signals · CPC title

• F02D41/062

  for starting (F02D41/061 takes precedence) · CPC title

• F02D41/042

  for stopping the engine · CPC title

• F02D41/1497

  With detection of the mechanical response of the engine · CPC title