Method for determining bearing play of exhaust-gas-turbocharger friction bearings

• US 10,119,419 B2
• Filed: 10/01/2010
• Issued: 11/06/2018
• Est. Priority Date: 10/16/2009
• Status: Active Grant

• Current Assignee: BorgWarner Incorporated
• Original Assignee: BorgWarner Incorporated
• Inventors: Walter, Norbert, Seiler, Andre
• Primary Examiner(s): Nguyen, Lam
• Application Number:
  US13/499,946
• Publication Number:
  US 20120197579A1
• Time in Patent Office: 2,958 Days
• Field of Search: 415177, 415407, 246169 A
• CPC Class Codes: F01D 25/166 Sliding contact bearing gas bearings F01D25/22
• CPC Class Codes: F02C 6/12 Turbochargers, i.e. plants for augmenting mechanical power output of internal-combustion piston engines by increase of charge pressure
• CPC Class Codes: F05D 2220/40 in turbochargers
• CPC Class Codes: F05D 2260/80 Diagnostics
• CPC Class Codes: F16C 17/246 related to wear, e.g. sensors for measuring wear
• CPC Class Codes: F16C 2360/24 Turbochargers
• CPC Class Codes: G01M 13/045 Acoustic or vibration analysis

Abstract

The invention relates to a method for determining bearing play of exhaust-gas-turbocharger friction bearings comprising the following method steps: accelerating the exhaust-gas turbocharger or the body group from standstill to a maximum rotational speed and at the same time registering the vibration acceleration by means of a sensor; determining the constant-tone frequency of the friction bearing at at least one rotational speed; plotting the determined constant-tone frequency in a diagram, in which bearing-play ranges determined experimentally in advance are assigned to constant-tone frequency ranges; and establishing whether or not the determined constant-tone frequency lies in a bearing-play target range.

Claims

1. A method for evaluating exhaust-gas-turbocharger friction bearings, comprising the following method steps:

accelerating a rotating body group of a turbocharger, the rotating body group comprising turbine wheel, compressor wheel, and shaft, said shaft supported by friction bearings, from standstill to a maximum rotational speed on a test bench and at the same time registering the vibration acceleration by means of a sensor;

using the registered vibration acceleration to determine a constant-tone frequency associated with the friction bearings at at least one rotational speed of the turbocharger;

looking up the determined constant-tone frequency on a diagram prepared by experimentally measuring constant-tone frequency and bearing-play of a number of friction bearings and showing a correlation between constant-tone frequency and bearing-play; and

if the determined constant-tone frequency corresponds to a bearing play associated with an acoustically conspicuous noise when in vehicle, rejecting the exhaust-gas-turbocharger friction bearings.

2. The method as claimed in claim 1, wherein a frequency spectrum is determined for determining the constant-tone frequency at a rotational speed of the exhaust-gas turbocharger determined experimentally in advance.

3. The method as claimed in claim 2, wherein the constant-tone frequency is determined during the production of the exhaust-gas turbocharger on an operational balancing bench.

4. The method as claimed in claim 3, wherein the oil temperature, the oil pressure, and/or the oil viscosity are taken into account as bearing-oil parameters.