Roller Crusher Gap Adjustment for Uncrushable Object Protection

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Solution Overview

Problem

Roller crushers face damage and increased operational costs due to uncrushable objects, and existing protective systems often require additional space and overdimensioned discharge chutes to handle bypassed material.

Innovation Solution

A method and system that dynamically adjust the gap width between rollers and control the in-feed rate to allow uncrushable objects to pass without a by-pass chute, using detectors to identify and manage uncrushable objects, and hydraulic mechanisms to adjust the gap and in-feed rate, ensuring safe operation and quick return to normal conditions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a by-pass chute is used to divert uncrushable objects, then the roller crusher is protected from damage, but the discharge chute becomes overloaded and the equipment requires more space

Engineering Contradiction:
Improveprotection from uncrushable objectsVSAvoiddischarge chute capacity
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The gap between rollers is made dynamically adjustable rather than fixed. When uncrushable objects are detected, the gap width is increased to allow these objects to pass through without damaging the rollers. This dynamic adjustment protects the crusher while maintaining normal crushing operation for valid material, avoiding the need for a by-pass chute that would overload the discharge chute.

Inventive Principle:
Principle #15Dynamics

2Reliability

If a by-pass chute is used to divert uncrushable objects, then the roller crusher is protected from damage, but the equipment requires more space

Engineering Contradiction:
Improveprotection from uncrushable objectsVSAvoidequipment footprint
Core Design Contradiction:
ReliabilityVSArea of stationary object

Solution Approach 1:

The gap between rollers is made dynamically adjustable rather than fixed. When uncrushable objects are detected, the gap width is increased to allow these objects to pass through without damaging the rollers. This dynamic adjustment protects the crusher while maintaining normal crushing operation for valid material, avoiding the need for a by-pass chute that would require additional space.

Inventive Principle:
Principle #15Dynamics

3Reliability

If the gap is opened wide to allow uncrushable objects to pass, then protection is achieved, but material flow control becomes difficult

Engineering Contradiction:
Improveprotection from uncrushable objectsVSAvoidmaterial flow control
Core Design Contradiction:
ReliabilityVSEase of operation

Solution Approach 1:

The in-feed rate is restricted before the uncrushable object reaches the gap, creating a controlled flow that gives sufficient time for the gap to open wide enough to accommodate the object. This preliminary action ensures that material flow remains manageable even when the gap is widened for protection.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system uses detection of uncrushable objects to trigger automatic adjustment of the gap width and in-feed rate. This feedback mechanism ensures the gap opens appropriately when needed while maintaining normal operation when uncrushable objects are not present, preserving ease of material flow control.

Inventive Principle:
Principle #23Feedback

Data Source

PatentEP2653233B1Roller crusher, and method of protecting a roller crusher from uncrushable objects
Publication Date: 2014.06.18 METSO MINERALS INDUSTRIES INC
  • EP2653233B1 patent drawingFigure 1
  • EP2653233B1 patent drawingFigure 2
  • EP2653233B1 patent drawingFigure 3

AI summary

A method of protecting a roller crusher (1), having two rollers (2) separated by a gap (3), from uncrushable objects (T) is disclosed. The method comprises the steps of: detecting an uncrushable object (T) in an in-feed stream of material (M), opening a gap (3) between said rollers to a by-pass width, which is significantly larger than an operational width, such that said uncrushable object is permitted to pass through said gap (3), restricting an in-feed (4) to said gap (3), such that material is fed to said gap (3) at a restricted in-feed rate, determining that said uncrushable object (T) has passed through said gap (3), reducing said gap (3) to said operational width, and opening said in-feed (4) to said gap (3), such that material (M) is fed to said gap (3) at an operational in-feed rate. A roller crusher (1) having a protective system for protecting the roller crusher (1) from uncrushable objects (T) is also disclosed.