Impeller Blade Conformity to Chopper Envelope

Solution Overview

Problem

Existing agricultural combine designs face challenges in the efficient transfer of harvested crop residue due to the need for maintaining a certain distance between the straw chopper and impeller blades, which can result in blockages and reduced throughput.

Innovation Solution

A harvested crop residue chopper and distribution arrangement featuring a straw chopper with a rotor rotating about a horizontal axis and impeller blowers with vertically extending axes, where the impeller blades have non-parallel outer edges that conform to the chopper knife envelope, allowing for a reduced spacing and improved crop transfer without collision.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If the outer edges of impeller blades are oriented parallel to the axis of rotation, then the impeller blower can be designed with a simple cylindrical structure, but a certain distance must be maintained between the straw chopper and impeller blower to avoid collision, resulting in reduced throughput and potential blockages

Engineering Contradiction:

Improveimpeller blower structure simplicityVSAvoidcrop residue transfer efficiency

Core Design Contradiction:

Ease of manufactureVSProductivity

Solution Approach 1:

The impeller blade outer edges are designed with non-uniform geometry: the lower portion extends parallel to the axis of rotation for structural simplicity, while the upper portion is angled or curved to conform to the chopper knife envelope. This local variation in blade geometry allows the impeller blower to be positioned closer to the straw chopper without collision, improving crop residue transfer efficiency while maintaining manufacturing feasibility.

Inventive Principle:

Principle #3Local quality

2Productivity

If the spacing between the straw chopper and impeller blower is reduced to improve crop transfer, then throughput increases, but collision between chopper knives and impeller blades may occur

Engineering Contradiction:

Improvecrop residue throughputVSAvoidcollision avoidance

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

The impeller blade outer edges are designed with non-uniform geometry: the lower portion extends parallel to the axis of rotation for structural simplicity, while the upper portion is angled or curved to conform to the chopper knife envelope. This local variation in blade geometry allows the impeller blower to be positioned closer to the straw chopper without collision, improving crop residue transfer efficiency while maintaining manufacturing feasibility.

Inventive Principle:

Principle #3Local quality

3Productivity

If the impeller blades are positioned closer to the straw chopper, then blockages are prevented and throughput increases, but the risk of collision between chopper knives and impeller blades increases

Engineering Contradiction:

Improvecrop residue flow efficiencyVSAvoidcollision risk

Core Design Contradiction:

ProductivityVSObject-affected harmful factors

Solution Approach 1:

The impeller blade outer edges are designed with non-uniform geometry: the lower portion extends parallel to the axis of rotation for structural simplicity, while the upper portion is angled or curved to conform to the chopper knife envelope. This local variation in blade geometry allows the impeller blower to be positioned closer to the straw chopper without collision, improving crop residue transfer efficiency while maintaining manufacturing feasibility.

Inventive Principle:

Principle #3Local quality

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 configuration enhances the flow and transfer of crop residue by reducing the gap between the straw chopper and impeller blower, preventing blockages and increasing throughput while maintaining a compact and efficient design.

Implementation Method 1

impeller blades that can be brought into rotation about an axis of rotation by an appropriate drive. The axis of rotation of the impeller blades extends vertically

Methodology Applied

Scientific EffectCentrifugal force: Centrifugal Force

Data Source

PatentUS8864561B2Harvested crop residue chopper and distribution arrangement for a combine with an impeller blower whose shape conforms to the contour of the straw chopper

Publication Date: 2014.10.21 DEERE & CO

AI summary

The invention concerns a harvested crop residue chopper and distribution arrangement for a combine (10) with a straw chopper (60) with a rotor (74) that can be brought into rotation about a horizontal axis (98) with chopper blades (76) fastened thereto that define an outer envelope (96), and with at least one impeller blower (82) arranged downstream of the straw chopper (60) with impeller blades (84) that can rotate about an axis of rotation (88) that extends vertically, in which the impeller blades (84) are provided with outer edges (94) that conform to the envelope (96) of the chopper knives (76) and follow it very closely and are not in contact with it.