Method for actively dampening a start-up resonance of a torsional damper when starting an internal combustion engine

Patent metadata

Field	Value
Publication number	US-11519377-B2
Application number	US-201917421806-A
Country	US
Kind code	B2
Filing date	Dec 10, 2019
Priority date	Jan 16, 2019
Publication date	Dec 6, 2022
Grant date	Dec 6, 2022

Abstract

A method actively dampens a start-up resonance of a torsional damper when starting an internal combustion engine. The torsional damper ( 4 ) is fixed between an internal combustion engine ( 1 ) and a secondary side ( 5 ) of a torsional elasticity, and the internal combustion engine ( 1 ) is started using a starter generator ( 3 ) arranged on a side of the internal combustion engine ( 1 ) counter to the torsional elasticity. A counter excitation is applied to a torque generated by the starter generator ( 3 ) when the internal combustion engine ( 1 ) is started, which counter excitation is modulated on the basis of a parameter of the internal combustion engine ( 1 ) which changes when the internal combustion engine ( 1 ) is being started.

First claim

The invention claimed is:

1. A method for actively dampening a start-up resonance of a torsional damper when starting an internal combustion engine, comprising:
fixing the torsional damper between the internal combustion engine and a secondary side of a torsional elasticity,
starting the internal combustion engine using a starter arranged on a side of the internal combustion engine opposite the torsional elasticity,
applying a counter excitation to a torque generated by the starter while the internal combustion engine is started, which counter excitation is modulated based on a parameter of the internal combustion engine which changes when the internal combustion engine is being started, and
shifting a phase of the counter excitation to take into account a rigidity of a belt drive arranged between the starter and the internal combustion engine.

2. The method according to claim 1 , wherein the parameter of the internal combustion engine is a crankshaft angle with a harmonic excitation of the nth order of the internal combustion engine.

3. The method according to claim 1 , further comprising setting a magnitude of the counter excitation based on a speed of the internal combustion engine and/or a speed difference and/or rotation angle difference between the internal combustion engine and starter or internal combustion engine and transmission.

4. The method according to claim 1 , wherein the counter excitation is a sine function.

5. The method according to claim 1 , further comprising exceeding a nominal torque of the starter during the starting process to superimpose the counter excitation on the torque of the starter.

6. The method according to claim 1 , further comprising reducing a mean torque of the starter during the starting process to such that superposition of the counter excitation does not exceed a maximum value.

7. The method according to claim 1 , further comprising reducing a magnitude of the counter excitation during the starting process in an upper speed range of the internal combustion engine.

8. A powertrain comprising:
an internal combustion engine;
a torsional damper fixed between the internal combustion engine and a secondary side of a torsional elasticity; and
a starter coupled to the engine via a belt; wherein
a counter excitation is applied to a torque generated by the starter while the internal combustion engine is being started, which counter excitation is modulated based on a crankshaft angle of the internal combustion engine.

9. The powertrain according to claim 8 , wherein a magnitude of the counter excitation is set on the basis of a speed of the internal combustion engine.

10. The powertrain according to claim 9 , wherein the magnitude of the counter excitation is reduced during the starting process in an upper speed range of the internal combustion engine.

11. The powertrain according to claim 8 , wherein a magnitude of the counter excitation is set on the basis of a speed difference between the internal combustion engine and the starter.

12. The powertrain according to claim 8 , wherein a magnitude of the counter excitation is set on the basis of a rotation angle difference between the internal combustion engine and the starter.

13. The powertrain according to claim 8 , wherein the counter excitation is a sine function.

14. The powertrain according to claim 8 , wherein superposition of the counter excitation results in a nominal torque of the starter being exceeded during the starting process.

15. The powertrain according to claim 8 , wherein a mean torque of the starter is reduced during the starting process such that superposition of the counter excitation does not result in exceeding a maximum value.

16. The powertrain according to claim 8 , wherein a phase of the counter excitation is shifted to take into account a rigidity of the belt.

17. A powertrain comprising:
an internal combustion engine;
a torsional damper fixed between the internal combustion engine and a secondary side of a torsional elasticity; and
a starter coupled to the engine via a belt; wherein
a counter excitation is applied to a torque generated by the starter while the internal combustion engine is being started, which counter excitation is modulated based on a parameter of the internal combustion engine which changes when the internal combustion engine is being started.

18. The powertrain according to claim 17 , wherein a magnitude of the counter excitation is set based on a speed of the internal combustion engine.

19. The powertrain according to claim 17 , wherein a magnitude of the counter excitation is set based on at least one of a speed difference between the internal combustion engine and the starter and a rotation angle difference between the internal combustion engine and the starter.

20. The powertrain according to claim 17 , wherein a phase of the counter excitation is shifted to take into account a rigidity of the belt.

Assignees

• Schaeffler Technologies Ag

Inventors

• Krause Thorsten
• Schenck Kai
• Pennec Bertrand

Classifications

• F02N11/0851 Primary

  characterised by means for controlling the engagement or disengagement between engine and starter, e.g. meshing of pinion and engine gear · CPC title

• F02N15/10 Primary

  Safety devices not otherwise provided for · CPC title

• F02N2200/022

  Engine speed · CPC title

• F02N2200/04

  said parameters being related to the starter motor · CPC title

• F02D2009/0233

  Engine vibration · CPC title