Round Baler Wrap System Torque Control for Ejection Trajectory

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing round balers face challenges in controlling the mesh trajectory of wrap material as it is ejected from the nip between spool rollers, leading to misalignment and blockage of the wrap material from entering the baling chamber.

Innovation Solution

A round baler with a torque controller system that adjusts the torque transmitted to the spool rollers based on the current weight of the supply roll of wrap material, ensuring a desired acceleration rate and aligning the leading edge of the wrap material with the access into the baling chamber.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the wrap material is ejected from the nip between spool rollers with high acceleration, then the wrapping speed is improved, but the ejection trajectory becomes unpredictable and misaligned with the access

Engineering Contradiction:
Improvewrapping speedVSAvoidejection trajectory alignment
Core Design Contradiction:
ProductivityVSManufacturing precision

Solution Approach 1:

The system dynamically adjusts the acceleration rate of the spool rollers based on the real-time weight of the supply roll. As the supply roll weight decreases during the wrapping cycle, the acceleration rate is increased to maintain consistent ejection trajectory and leading edge alignment with the access, thereby resolving the contradiction between maintaining high wrapping speed and ensuring precise trajectory control

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The controller modifies the acceleration parameter of the spool rollers as a function of supply roll weight. By changing the acceleration rate parameter dynamically throughout the wrapping cycle, the system maintains optimal ejection trajectory alignment despite variations in supply roll mass, thus achieving both high productivity and manufacturing precision

Inventive Principle:
Principle #35Parameter changes

2Reliability

If the supply roll weight varies during the wrapping cycle, then the available torque from the driver becomes insufficient to maintain consistent acceleration, but increasing torque continuously would waste energy

Engineering Contradiction:
Improveacceleration consistencyVSAvoidenergy consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The system employs a feedback mechanism where the weight of the supply roll is continuously monitored and used to adjust the torque applied by the driver. This closed-loop control ensures that torque is optimized based on actual conditions, maintaining consistent acceleration and ejection trajectory while avoiding unnecessary energy consumption that would result from continuous maximum torque application

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The driver torque is dynamically adjusted throughout the wrapping cycle based on supply roll weight variations. The system transitions from high torque when the supply roll is heavy to reduced torque when the supply roll is lighter, maintaining reliable acceleration consistency while optimizing energy usage by matching torque output to actual operational needs

Inventive Principle:
Principle #15Dynamics

3Reliability

If the leading edge of the wrap material does not align with the access, then the wrap material is blocked from entering the baling chamber, but adjusting the ejection angle requires complex mechanical modifications

Engineering Contradiction:
Improvewrap material feed reliabilityVSAvoidmechanical adjustment complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The system replaces complex mechanical adjustments for ejection trajectory control with a control system that dynamically adjusts spool roller acceleration rates. By using electronic control and software algorithms instead of mechanical linkages or adjustable components, the system achieves reliable wrap material feed alignment without increasing mechanical device complexity

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

Solution Approach 2:

Instead of mechanically adjusting the ejection angle, the system changes the acceleration parameter of the spool rollers to control the ejection trajectory. This parameter-based control approach achieves reliable alignment of the leading edge with the access while avoiding the complexity of mechanical adjustment mechanisms

Inventive Principle:
Principle #35Parameter changes

Data Source

PatentEP4151076B1Bale wrapping system with proportional cycle acceleration
Publication Date: 2025.05.28 DEERE & CO
  • EP4151076B1 patent drawingFigure 1
  • EP4151076B1 patent drawingFigure 2
  • EP4151076B1 patent drawingFigure 3

AI summary

A method of controlling a wrap system of a round baler includes determining a current characteristic of a supply roll of wrap material related to a current weight of the supply roll, and controlling rotation of a pair of spool rollers based on the current characteristic of the supply roll. As the current characteristic indicates a decrease in weight, the rotation of the pair of spool rollers is controlled to achieve a desired acceleration rate of the spool rollers, such that a leading edge of the wrap material is ejected from a nip formed between the pair of spool rollers at an ejection trajectory that is within an allowable angular range relative to a tangent of the nip, so that the leading edge of the wrap material passes through an access and into a baling chamber of the round baler.