Forage Harvester Knife Alignment Tool for Worn Chopper Adjustment

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Solution Overview

Problem

The maintenance of chopper knives in forage harvesters is time-consuming, and adjusting the position of worn knives relative to the shear bar is challenging, leading to reduced chopping quality and increased energy consumption.

Innovation Solution

An adjustment tool with edge alignment pins and fixings is used to simplify the process of positioning chopper knives relative to the chopper drum, allowing for precise adjustment without requiring alignment to the shear bar, thereby ensuring correct interaction and reducing the risk of damage.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If chopper knives are adjusted manually without a specialized tool, then the adjustment process becomes simpler in terms of equipment, but the adjustment time increases and precision decreases

Engineering Contradiction:
Improveease of knife adjustmentVSAvoidmaintenance time
Core Design Contradiction:
Ease of operationVSLoss of time

Solution Approach 1:

The adjustment tool serves as an intermediary device between the operator and the chopper knife. It includes a frame with fixings that engage with bores in the knife support, and edge alignment pins that project to engage with non-wearing edges of the knife. This intermediary tool standardizes the adjustment process, making it both easier to operate and faster to complete.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The adjustment tool is designed with pre-positioned edge alignment pins that correspond to predetermined amounts of wear. This preliminary positioning of the pins allows the knife to be quickly adjusted to the correct position without requiring the operator to measure or calculate the adjustment, thereby reducing maintenance time while improving ease of operation.

Inventive Principle:
Principle #10Preliminary action

2Manufacturing precision

If chopper knives are adjusted without alignment pins, then the adjustment process is faster to set up, but the positioning precision and chopping quality deteriorate

Engineering Contradiction:
Improveknife positioning precisionVSAvoidadjustment tool complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The adjustment tool is segmented into distinct functional components: a frame structure, fixings for engagement with the knife support bores, and multiple edge alignment pins positioned at predetermined locations. This segmentation allows each component to perform its specific function independently, ensuring precise knife positioning while keeping the overall device design manageable and not overly complex.

Inventive Principle:
Principle #1Segmentation

3Reliability

If the shear bar is used as a reference for knife adjustment, then the cutting gap can be maintained, but the risk of damage to the shear bar and injury to operators increases

Engineering Contradiction:
Improvecutting gap maintenanceVSAvoidrisk of damage and injury
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The adjustment tool extracts the reference function from the shear bar by incorporating dedicated edge alignment pins that engage with non-wearing edges of the knife itself. This removes the need to use the shear bar as a reference during adjustment, thereby maintaining cutting gap reliability through the pins while eliminating the harmful effects of potential shear bar damage and operator injury.

Inventive Principle:
Principle #2Taking out (Extraction)

4Manufacturing precision

If chopper knives are adjusted frequently to maintain quality, then chopping quality is preserved, but energy consumption and operational interruptions increase

Engineering Contradiction:
Improvechopping qualityVSAvoidharvesting efficiency
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

The adjustment tool incorporates edge alignment pins positioned for predetermined amounts of wear (e.g., new knife position, 50% wear position, 75% wear position). This preliminary configuration of pins at standardized wear intervals allows operators to quickly adjust knives at predetermined maintenance intervals without frequent inspections, thereby maintaining chopping quality while reducing operational interruptions and preserving harvesting efficiency.

Inventive Principle:
Principle #10Preliminary action

Data Source

PatentEP4649817A1An adjustment tool for adjusting the chopper knives of a forage harvester
Publication Date: 2025.11.19 AGCO INT GMBH
  • EP4649817A1 patent drawingFigure 1
  • EP4649817A1 patent drawingFigure 2
  • EP4649817A1 patent drawingFigure 3

AI summary

An adjustment tool (80) is provided for adjusting the chopping knives (61) of a chopper drum of a forage harvester. A frame (82) is provided with a pair of fixings (84) for engaging with a bore (50) through the chopper knife (61). Edge alignment pins (86) project from the frame (82) for engaging with non-wearing edges (64, 66) of a chopper knife (61), thereby setting a position of non-wearing edges (64, 66) of the chopper knife (61) relative to the bores (50). The edge alignment pins (86) are positioned for alignment of a chopper knife (61) with a predetermined amount of wear.