Grinding Stone Measuring Electrode Vibration Damping

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The existing systems for detecting contact between a grinding stone and the back of rotating knives in forage harvesters face difficulties due to oscillation caused by radial movement, which complicates the assessment of knife wear.

Innovation Solution

A vibration damper with a spring element and damping element is used to decouple the measuring electrode from the grinding stone, ensuring consistent contact and preventing deviation, while a guide bushing prevents sticking and maintains the measuring electrode's position.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If the grinding wheel is guided radially onto the back of rotating knives, then the contact detection enables wear assessment, but radial movement causes vibration that complicates measurement

Engineering Contradiction:
Improvecontact detection precisionVSAvoidmeasurement stability
Core Design Contradiction:
Measurement precisionVSStability of the object's composition

Solution Approach 1:

A vibration damper is introduced as an intermediary element between the measuring electrode and the grinding wheel. This damper absorbs radial vibrations from the grinding wheel, allowing the measuring electrode to maintain stable contact with the knife back despite the grinding wheel's radial movement and vibration during operation.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The vibration damper converts the harmful radial vibrations of the grinding wheel into beneficial damping action. By absorbing these vibrations, the system transforms the unstable radial movement into a stable measurement condition, where the measuring electrode remains in consistent contact with the workpiece.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

2Device complexity

If the measuring electrode is rigidly connected to the grinding wheel, then the structure is simple, but vibrations cause loss of contact during measurement

Engineering Contradiction:
Improveconnection structure simplicityVSAvoidcontact reliability
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The vibration damper serves as a mediating connection between the measuring electrode and the grinding wheel. Instead of a rigid direct connection, the damper provides a flexible linkage that maintains electrical and mechanical connection while isolating the measuring electrode from vibrations, ensuring reliable contact detection.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Adaptability or versatility

If the measuring electrode moves freely, then it can adapt to vibrations, but it may adhere to the grinding wheel and lose proper positioning

Engineering Contradiction:
Improvevibration adaptationVSAvoidelectrode positioning precision
Core Design Contradiction:
Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

The guide bushing acts as an intermediary constraint that allows the measuring electrode to move vertically to accommodate vibrations while preventing lateral movement and adhesion to the grinding wheel. This ensures the electrode maintains precise positioning relative to the knife back during measurement.

Inventive Principle:
Principle #24Intermediary (Mediator)

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

This solution allows for improved detection of contact between the grinding stone and knife back, enabling continuous assessment of knife wear by maintaining contact even during vibrations, thus enhancing the accuracy of wear state determination.

Implementation Method 1

a vibration damper with a spring element and a damper element, which connects the measuring electrode on the opposite side to the grinding wheel

Methodology Applied
Scientific EffectVibration damping: Damping

Implementation Method 2

A spring element of the vibration damper is pre-tensioned

Methodology Applied
Scientific EffectSpring element: Spring

Data Source

PatentEP3769607B1Grinding stone and grinding method
Publication Date: 2022.08.10 CLAAS SELBSTFAHRENDE ERNTEMASCHINEN GMBH
  • EP3769607B1 patent drawingFigure 1
  • EP3769607B1 patent drawingFigure 2
  • EP3769607B1 patent drawingFigure 3

AI summary

A grinding stone (15) is disclosed, comprising a rod-shaped measuring electrode (16) which is guided through the grinding stone (15) from a counter-side (19) opposite the working side (17) and is connected to the grinding stone (15). A method for grinding knives rotatable about an axis of a comminution unit is also disclosed, wherein a working side (17) of a grinding stone (15) is guided in a direction radial to the axis onto a knife back (18) of the knives, and wherein contact between the grinding stone (15) and the knife backs (18) is detected by means of a rod-shaped measuring electrode (16) which is guided through the grinding stone (15) from a counter-side (19) opposite the working side (17) and is connected to the grinding stone (15). To improve the detection of contact, the invention proposes that the measuring electrode (16) be connected to the grinding stone (15) in a spring-loaded and damped manner in the radial direction.