Vehicle Brake Pad Noise Control via Electronic Pre-Loading

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Vehicle brake systems generate unpleasant noises, such as reversing clicks and rattling, due to the play between brake pads and their holders, which can occur during changes in direction or when driving over uneven road surfaces, and existing solutions like springs are inadequate in preventing these noises at higher acceleration levels.

Innovation Solution

An electronic control unit detects changes in vehicle direction and uneven road surfaces, initiating a minimal, imperceptible deceleration process through sensors and measurement technology, ensuring the brake pads are slowly applied within the shaft clearance without noise, using a light braking pressure that is imperceptible to the driver.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If springs are used to prevent rattling noise, then noise prevention is improved up to a defined acceleration level, but unwanted rattling noises still occur when acceleration exceeds this level

Engineering Contradiction:
Improverattling noiseVSAvoidnoise prevention effectiveness
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The electronic control unit initiates a light braking process before the vehicle reaches high acceleration levels when driving over uneven road surfaces. This preliminary action prevents the brake pads from accelerating within the clearance and striking the caliper components, thereby preventing rattling noise before it occurs rather than just mitigating it after springs fail at high acceleration levels

Inventive Principle:
Principle #10Preliminary action

2Speed

If brake pads are rapidly accelerated during braking after direction change, then braking response is improved, but loud clacking noise known as reversing clack occurs

Engineering Contradiction:
Improvebraking response speedVSAvoidreversing clack noise
Core Design Contradiction:
SpeedVSObject-affected harmful factors

Solution Approach 1:

The electronic control unit detects a change between forward and reverse travel and initiates a light braking process before the driver applies the brakes. This preliminary action ensures that the brake pads are already in contact with the brake disc and properly positioned, so when the driver subsequently applies the brakes, the brake pads do not slide rapidly within the clearance and produce reversing clack noise

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The light braking process creates a preliminary counteracting force that prevents the brake pads from moving rapidly within the clearance during subsequent braking. By applying a small braking force in advance, the system counteracts the tendency of the brake pads to slide and strike the caliper components, thereby preventing the reversing clack noise while maintaining ready-to-brake conditions

Inventive Principle:
Principle #9Preliminary anti-action

3Object-affected harmful factors

If minimal deceleration is applied to prevent brake pad impact noise, then noise prevention is improved, but driver perceivability of braking remains imperceptible

Engineering Contradiction:
Improvebrake pad impact noiseVSAvoiddriver perception of braking
Core Design Contradiction:
Object-affected harmful factorsVSEase of operation

Solution Approach 1:

The electronic control unit applies a light braking pressure that is sufficient to prevent brake pad impact noise but minimal enough to be imperceptible to the driver. This partial action approach uses just enough braking force to achieve the desired noise prevention effect without creating a noticeable deceleration that would interfere with the driver's perception or control of the vehicle

Inventive Principle:
Principle #16Partial or excessive action

Data Source

PatentEP3411274B1Method for operating a vehicle brake system
Publication Date: 2021.07.28 BAYERISCHE MOTOREN WERKE AG
  • EP3411274B1 patent drawingFigure 1
  • EP3411274B1 patent drawingFigure 2a~2ad
  • EP3411274B1 patent drawingFigure 2b~2bh

AI summary

The invention relates to a method for operating a vehicle brake system, which has at least one brake pad and a friction partner interacting with the same, wherein an electronic control unit detects a state at the brake pad and/or the friction partner and, depending on the state, triggers a pressing between the brake pad and friction partner in such a way that substantially no vehicle deceleration is perceptible for a vehicle passenger. The electronic control unit thereby detects as the aforementioned state a change between forward and reverse driving and/or a vertical movement and/or a source of a future vertical movement of the vehicle wheel and/or of a vehicle body of the vehicle. Noises can be reduced in this way.