Haymaking Rotor Tine Force Sensing for Ground Contact Control

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Solution Overview

Problem

Existing haymaking machines face issues with unwanted forage contamination and crop loss due to tine tips penetrating the soil, as existing systems do not adequately monitor and adjust the distance of tine tips from the ground, leading to inefficiencies in the harvesting process.

Innovation Solution

A haymaking machine equipped with measuring devices on spring tines to detect forces acting on each tine, allowing for automatic adjustment of the distance and angle of the tines relative to the ground based on measured force differences, using strain gauges for signal detection and a control unit for parameter generation.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the spring tine tips are positioned to lift the crop from the grass stubble, then the conveying efficiency is improved, but the risk of soil penetration and forage contamination increases

Engineering Contradiction:
Improveconveying efficiencyVSAvoidforage contamination
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent implements a feedback control system where force sensors mounted on the spring tines continuously monitor the contact force between tine tips and the ground. When the measured force exceeds a predetermined threshold indicating soil penetration, the control unit automatically adjusts the rotor height to increase the clearance between tine tips and ground, thereby preventing further contamination while maintaining optimal conveying efficiency during normal operation

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The system dynamically changes the operational parameters by adjusting the rotor height based on real-time force measurements. The control unit modifies the vertical position of the rotor to optimize the distance between spring tine tips and ground surface, transitioning between different operational states (normal conveying vs. soil contact prevention) to resolve the contradiction between productivity and contamination prevention

Inventive Principle:
Principle #35Parameter changes

2Productivity

If the rotor height is adjusted based on crop material amount and moisture content, then the conveying conditions are optimized, but the actual distance between tine tips and ground remains unmonitored

Engineering Contradiction:
Improveconveying conditionsVSAvoidtine-to-ground distance monitoring
Core Design Contradiction:
ProductivityVSMeasurement precision

Solution Approach 1:

The patent replaces indirect mechanical height adjustment mechanisms with direct force-based sensing and control. Instead of relying on mechanical positioning systems that are difficult to monitor precisely, the invention uses force sensors to directly detect soil contact conditions and translates these measurements into automated height adjustments, achieving precise monitoring of the effective tine-to-ground distance through force feedback rather than direct positional measurement

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

3Reliability

If manual monitoring of tine-to-ground distance is performed, then contamination can be detected, but the operator monitoring effort and time consumption increase

Engineering Contradiction:
Improvecontamination detectionVSAvoidoperator monitoring effort
Core Design Contradiction:
ReliabilityVSLoss of time

Solution Approach 1:

The system performs self-monitoring and self-adjustment through automated force sensing and control. The spring tines equipped with force sensors continuously self-assess their contact condition with the ground, and the control unit automatically adjusts the rotor height without requiring operator intervention. This self-service mechanism maintains high reliability in contamination detection while eliminating the time-consuming manual monitoring previously required

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The automated feedback loop continuously monitors force on the spring tines and adjusts rotor height in real-time based on detected soil contact conditions, providing reliable contamination detection without requiring continuous operator attention or manual intervention

Inventive Principle:
Principle #23Feedback

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

Reduces operator monitoring effort and minimizes forage contamination and crop loss by ensuring tine tips do not penetrate the soil, optimizing the work result through precise tine positioning.

Implementation Method 1

the force acting on each spring tine is determined by detecting a deformation of the spring tine

Methodology Applied
Scientific EffectStrain gauge measurement: Deformation

Data Source

PatentEP4491008B1Haymaking machine
Publication Date: 2025.12.03 MASCHINENFABRIK BERNARD KRONE GMBH & CO KG
  • EP4491008B1 patent drawingFigure 1
  • EP4491008B1 patent drawingFigure 2
  • EP4491008B1 patent drawingFigure 3

AI summary

Haymaking machine for tedding or windrowing agricultural straw or leaves, comprising at least one tedding or raking rotor (3) arranged on a machine beam (4), which is driven in a working and operating position around an approximately vertical axis (5), and is provided with at least two or more tine arms (6) evenly distributed in a circumferential direction around the vertical axis (5) and oriented approximately radially, wherein at least one first spring tine (7) having a first length (12) is arranged on the tine arms (6), wherein at least one second spring tine (8) having a second length (13) that is shorter than the first length (12) is arranged on the tedding or raking rotor (3), wherein the tedding or raking rotor (3) comprises at least one first measuring means (10) which interacts with the first spring tine (7), and a second measuring means (11) which interacts with the second spring tine (8). where the measuring instruments (10,11) each are designed to measure a force acting on the respective spring prong (7, 8).