Pneumatic Disc Brake Wear Adjuster with Rolling-Body Coupling

Solution Overview

Problem

Pneumatically actuated disc brakes require a mechanical step-up to generate sufficient application force, leading to excessive wear travel due to the limited force of the brake cylinder, necessitating a wear adjusting apparatus that is costly and has high accuracy requirements, affecting operational reliability.

Innovation Solution

A wear adjusting apparatus for pneumatically actuated disc brakes featuring an overload coupling with a rolling-body coupling and friction clutches on both sides, implemented with low production costs and reduced accuracy requirements, using non-cutting forming and ball bearings for low hysteresis and adaptability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a precision clamping roller freewheel is used for unidirectional coupling, then the adjuster can be rotated in the feed direction only, but the production costs increase and manufacturing precision requirements become high

Engineering Contradiction:

Improveoperational reliabilityVSAvoidproduction costs

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent replaces the expensive precision clamping roller freewheel with a simpler, cheaper unidirectional coupling mechanism that uses a cam profile and friction elements. This simpler mechanism achieves the same unidirectional rotation function without requiring high manufacturing precision, thereby reducing production costs while maintaining operational reliability.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent changes the design parameters of the unidirectional coupling by using a cam profile with specific geometric parameters and friction coefficients instead of precision rollers. This parameter change allows the mechanism to function reliably with lower manufacturing tolerances, reducing both production costs and manufacturing precision requirements.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If a precision clamping roller freewheel is used for unidirectional coupling, then the adjuster can be rotated in the feed direction only, but the manufacturing precision requirements become high

Engineering Contradiction:

Improveoperational reliabilityVSAvoidaccuracy requirements

Core Design Contradiction:

ReliabilityVSManufacturing precision

Solution Approach 1:

The patent replaces the expensive precision clamping roller freewheel with a simpler, cheaper unidirectional coupling mechanism that uses a cam profile and friction elements. This simpler mechanism achieves the same unidirectional rotation function without requiring high manufacturing precision, thereby reducing production costs while maintaining operational reliability.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

Solution Approach 2:

The patent changes the design parameters of the unidirectional coupling by using a cam profile with specific geometric parameters and friction coefficients instead of precision rollers. This parameter change allows the mechanism to function reliably with lower manufacturing tolerances, reducing both production costs and manufacturing precision requirements.

Inventive Principle:

Principle #35Parameter changes

3Ease of manufacture

If friction clutches are used in the unidirectional coupling, then production costs are reduced, but the friction moment must be controllable

Engineering Contradiction:

Improveproduction costsVSAvoidsettable friction moments

Core Design Contradiction:

Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The patent incorporates a dynamically adjustable friction clutch mechanism that allows the friction moment to be varied during operation. This is achieved through an adjustable spring pressure or variable cam profile that can be modified to change the friction characteristics, providing adaptability while using simpler, lower-cost friction-based coupling instead of precision rollers.

Inventive Principle:

Principle #15Dynamics

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The solution reduces production costs while maintaining high operational reliability, achieving simple construction, low tolerance sensitivity, and adaptable settings with settable friction moments, enhancing the disc brake's wear adjustment mechanism.

Implementation Method 1

The unidirectional coupling has a rolling-body coupling and friction clutches, which are arranged on both sides of the rolling-body coupling

Methodology Applied

Scientific EffectRolling contact: Roller

Implementation Method 2

The unidirectional coupling has a rolling-body coupling and friction clutches, which are arranged on both sides of the rolling-body coupling

Methodology Applied

Scientific EffectFriction: Friction

Data Source

PatentUS7694784B2Adjusting apparatus for a pneumatically actuated disc brake

Publication Date: 2010.04.13 KNORR BREMSE SYSTEME FUER NUTZFAHIZEUGE GMBH

AI summary

An adjusting apparatus for a pneumatically actuated disc brake, in particular for arrangement in a rotatable spindle, having an overload coupling and a unidirectional coupling, is distinguished by the fact that the unidirectional coupling has a rolling-body coupling and friction clutches which are arranged on both sides of the rolling-body coupling.