Asymmetric Coupling Device for Support Wheels in Seed Drills
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Solution Overview
Problem
Existing precision seed drill agricultural machines face challenges with uneven seed distribution and varying seed furrow depths, especially at higher speeds, leading to increased time requirements and potential wear on machinery due to soil irregularities.
Innovation Solution
A coupling device is implemented that adjusts the vertical speed components of support wheels relative to the seed furrow forming means, ensuring the higher support wheel moves more significantly upwards than the lower one downwards, reducing vertical movement and acceleration, thus minimizing seed furrow depth variations and allowing for higher driving speeds.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If support wheels are coupled with equal vertical movement (traditional bogie effect), then load distribution is improved, but seed furrow depth variation increases
Solution Approach 1:
The coupling device is designed with asymmetric geometry where the first coupling member has a different effective lever arm length than the second coupling member. When one support wheel moves vertically, the asymmetric linkage causes the other wheel to move a different distance, creating unequal vertical movements that compensate for soil irregularities and maintain consistent seed furrow depth while still distributing load between wheels.
2Productivity
If driving speed is increased, then productivity is improved, but seed distribution uniformity deteriorates
Solution Approach 1:
The coupling device incorporates dynamic movement characteristics where the vertical speed components of the support wheels are different. The higher disposed support wheel has a greater vertical speed component than the lower disposed wheel, creating a dynamic compensation effect that maintains seed placement uniformity even at higher driving speeds where traditional equal-movement bogie systems fail.
3Force
If support wheels move with equal vertical displacement, then shock load distribution is improved, but seed furrow depth control deteriorates
Solution Approach 1:
The asymmetric coupling mechanism allows different vertical displacements of the support wheels while maintaining force balance. The unequal lever arm lengths in the coupling device create different displacement magnitudes that compensate for soil irregularities, ensuring consistent seed furrow depth control while still distributing shock loads effectively between the wheels.
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 solution results in more uniform seed placement, reduced wear on machinery, and increased driving speeds while maintaining consistent seed furrow depths, even over irregular terrain, by controlling the vertical movement and speed of the seed furrow forming means.
Implementation Method 1
the coupling device is adapted to provide a gearing such that at movement of the support wheels in relation to the seed furrow forming means, a vertical component of the speed in relation to the seed furrow forming means of the higher disposed support wheel is greater than a vertical component of the speed in relation to the seed furrow forming means of the lower disposed support wheel
Data Source
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AI summary
The invention refers to an agricultural machine comprising at least one soil cultivating device (2) comprising a seed furrow forming means (10), for forming a seed furrow (9a) in soil (9) over which the agricultural machine (1) moves, and a first and a second support wheel (11, 12), in addition to which the agricultural machine comprises at least one seed out feeding device (8) for distributing seeds to the seed furrow (9a). The support wheels (11, 12) are coupled with each other via a coupling device (15) which is arranged to provide a gearing such that at movement of the support wheels (11, 12) in relation to the seed furrow forming means (10) a vertical component (V 11) of the speed in relation to the seed furrow forming means (10) of the higher disposed support wheel (11) is greater than a vertical component (V 12) of the speed in relation to the seed furrow forming means (10) of the lower disposed support wheel (12). The mentioned gearing is such that the difference between the mentioned vertical components (V 11, V 12) of speeds of the support wheels (11, 12) in relation to the seed furrow forming means (10) increases when the height difference (AC) between the support wheels (11, 12) increases.