Reversing Straw Chopper Rotor for Combine Airflow Management

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Solution Overview

Problem

Prior agricultural combines experience reduced airflow and operational limitations due to blockages in the windrowing conduit when chopping straw, which restricts the free flow of air and increases internal pressure.

Innovation Solution

The agricultural combine features a residue management system with a straw chopper that rotates in two directions, allowing for both windrowing and chopping modes, along with a movable crop deflector and exhaust vent to enhance airflow by directing straw and chaff flows effectively and venting air outside the combine.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If the windrowing conduit is blocked by a door to enable straw chopping, then straw can be chopped and distributed over the ground, but airflow through the combine is restricted and internal pressure increases

Engineering Contradiction:
Improvestraw processing capabilityVSAvoidairflow rate
Core Design Contradiction:
Adaptability or versatilityVSProductivity

Solution Approach 1:

The straw chopper rotor is designed to rotate in two opposite directions: clockwise for windrowing mode and counter-clockwise for chopping mode. This dynamic reversal allows the same rotor to perform two different functions, eliminating the need for a blocking door and maintaining continuous airflow through the combine while providing versatile straw processing capability

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The single straw chopper rotor serves multiple functions by rotating in opposite directions: it acts as a windrowing rotor in one direction and a chopping rotor in the opposite direction. This multi-functionality resolves the contradiction by eliminating the need for separate mechanisms or blocking structures, thereby maintaining airflow while providing both windrowing and chopping capabilities

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If the windrowing conduit is blocked to deflect straw over the chopper rotor, then straw chopping is enabled, but the free flow of air out of the combine is prevented

Engineering Contradiction:
Improvechopping functionVSAvoidairflow freedom
Core Design Contradiction:
Adaptability or versatilityVSEase of operation

Solution Approach 1:

The rotor direction is dynamically reversed to enable chopping without blocking the airflow path. The counter-clockwise rotation directs straw downward for chopping while allowing air to flow freely over the top of the rotor and out through the windrowing conduit, maintaining ease of operation and airflow freedom

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP3409095B1Agricultural combine with reversing chopper rotor
Publication Date: 2021.06.09 DEERE & CO
  • EP3409095B1 patent drawingFigure 1
  • EP3409095B1 patent drawingFigure 2
  • EP3409095B1 patent drawingFigure 3

AI summary

An agricultural combine has a straw chopper that rotates in one direction in a straw chopping mode of operation and rotates in an opposing direction in a windrowing mode of operation.