Harvester Header Interlock Mechanism for Reel-Cutterbar Spacing

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Solution Overview

Problem

Existing interlock mechanisms for harvesting headers face issues with high reaction loads on the frame, frame deformation, and oil leakage due to direct load transfer and reliance on sensors, which can lead to interference between the reel and cutterbar during adjustments, especially when handling down crops.

Innovation Solution

An interlock mechanism with a linkage system that includes a wedge-like body connected to the cutterbar and a hydraulic cylinder, allowing for vertical adjustment of the reel relative to the cutterbar while maintaining a constant spacing, supported by guiding means like rollers and slots to prevent interference and optimize frame stability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the cutterbar is extended to forwardmost position, then the cutting capacity is improved, but the reel may interfere with the cutterbar causing damage

Engineering Contradiction:
Improvecutting capacityVSAvoidinterference prevention
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The reel arm is made dynamically adjustable through a hydraulic actuator that changes the reel's vertical position based on the cutterbar extension position. The linkage mechanism converts horizontal cutterbar movement into vertical reel movement, allowing the system to adapt its configuration dynamically rather than being fixed

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

A linkage mechanism acts as an intermediary between the cutterbar and reel, translating the cutterbar's fore-and-aft movement into corresponding reel position adjustments. This intermediary system coordinates the movement of both components to prevent interference while maintaining cutting capacity

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If the reel position is automatically adjusted on vertical flexure of the cutterbar, then the reliability is improved, but the load on the interlock mechanism becomes high

Engineering Contradiction:
Improvereel-cutterbar coordinationVSAvoidload on interlock mechanism
Core Design Contradiction:
ReliabilityVSForce

Solution Approach 1:

The linkage mechanism transforms the vertical adjustment problem into a horizontal-coupled-vertical movement system. By connecting reel position to cutterbar horizontal position through the linkage, the system uses the cutterbar's horizontal movement dimension to control reel vertical position, distributing loads more effectively across the mechanism

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

The patent replaces sensor-based electronic control systems with a purely mechanical linkage system that automatically coordinates reel and cutterbar positions through physical connectivity. This mechanical substitution eliminates complex electronics while providing reliable, load-distributed automatic adjustment

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

3Reliability

If the cam system is used to limit the vertical position of the reel arm, then the interference is prevented, but the load is transferred directly to the frame causing deformation

Engineering Contradiction:
Improveinterference preventionVSAvoidframe stability
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The linkage mechanism extracts the reel positioning function from the frame structure, creating an independent positioning system that does not rely on frame rigidity to limit reel movement. The reel arm connection point is positioned remote from the frame, separating the positioning function from the load-bearing frame structure

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The linkage mechanism serves as an intermediary that mediates between the reel arm and frame, preventing direct load transfer. The mechanism translates cutterbar position into reel position while distributing forces through the linkage components rather than concentrating them on the frame

Inventive Principle:
Principle #24Intermediary (Mediator)

4Device complexity

If the hydraulic lift cylinder is fixed to the frame, then the structure is simplified, but oil leakage occurs when the reel arm is forced upwardly

Engineering Contradiction:
Improvecylinder mounting structureVSAvoidsealing integrity
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The hydraulic cylinder mounting is made dynamic through the linkage mechanism, allowing the cylinder to move vertically in conjunction with reel position changes. This dynamic mounting prevents the cylinder rod from being pulled outward during reel upward movement, maintaining sealing integrity while adding minimal structural complexity

Inventive Principle:
Principle #15Dynamics

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

The solution effectively prevents interference between the reel and cutterbar during adjustments, reduces frame deformation, and avoids oil leakage by distributing loads away from the pivot point, maintaining optimal spacing and stroke range.

Implementation Method 1

a hydraulic cylinder extending between each reel arm and a corresponding side wall of said header frame to effect a generally vertical movement of said reel

Methodology Applied
Scientific EffectHydraulic actuation: Hydraulic Press

Data Source

PatentEP2143318B1Extendable header for harvesting machine
Publication Date: 2011.06.15 CNH IND BELGIUM NV
  • EP2143318B1 patent drawingFigure 1~2
  • EP2143318B1 patent drawingFigure 3

AI summary

A header (10) for a harvesting machine having a frame (11), a cutterbar (12) mounted on the frame operable to cut standing crop, the cutterbar being adjustable relative to the frame in a fore-and-aft direction, and a reel (15) rotatably supported between a pair of reel arms (16) pivotally mounted (17) on the frame and operable to sweep crop material towards and over the cutterbar, a hydraulic cylinder (20) extending between each reel arm (16) and a corresponding side wall of said header frame (11) to effect a generally vertical movement of said reel, comprising an interlock mechanism (70) operably interconnecting the cutterbar (12) and the hydraulic cylinder (20) at each side of the header for adjusting the vertical position of the reel in response to a fore-and-aft movement of the cutterbar to maintain substantially constant the spacing and avoiding interference between the reel and the cutterbar.