Haymaking Machine Rotor Arm Coupling Eliminates Rotational Play

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing haymaking machines experience rotational play between parts due to manufacturing tolerances, leading to shocks, noise, and increased wear, as existing coupling devices fail to compensate for this play during operation.

Innovation Solution

The coupling device incorporates inclined bearing faces that immobilize the first part with respect to the second part both axially and rotationally, eliminating rotational play and ensuring perfect torque transmission, even with normal manufacturing tolerances, through a single movement of the tensioning mechanism.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If traditional coupling devices with stop means and tension means are used to connect the first and second parts, then the parts can be easily assembled and disassembled, but rotational play between the parts causes shocks, noise, and increased wear during operation

Engineering Contradiction:
Improveease of assembly and disassemblyVSAvoidoperational smoothness and wear resistance
Core Design Contradiction:
Ease of operationVSReliability

Solution Approach 1:

The arm is divided into a first part carrying working tools and a second part linked to the rotor, connected by a coupling device that allows separate assembly while ensuring operational rigidity. The coupling device segments the connection function into axial positioning and rotational locking, resolving the contradiction between easy assembly and operational smoothness.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention introduces a new dimensional approach by using inclined bearing faces that convert axial movement into rotational locking. When the tensioning means moves axially, it forces the inclined faces to engage, which simultaneously locks rotation. This dimensional transformation eliminates rotational play without complicating the assembly process.

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

2Ease of manufacture

If manufacturing tolerances are accepted in traditional coupling devices, then production costs are reduced and assembly is simplified, but rotational play increases leading to shocks and accelerated wear

Engineering Contradiction:
Improvemanufacturing tolerance toleranceVSAvoidshocks and wear from rotational play
Core Design Contradiction:
Ease of manufactureVSObject-affected harmful factors

Solution Approach 1:

The invention converts the harmful effect of manufacturing tolerances into a beneficial feature. The inclined bearing faces are designed to automatically take up rotational play caused by tolerances through axial movement of the tensioning means. What was previously a harmful gap is transformed into a self-compensating mechanism that eliminates shocks and wear during operation.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The invention changes the geometric parameters of the coupling device by introducing inclined bearing faces with specific angles. This parameter change allows the coupling device to transform axial force into rotational locking, automatically compensating for manufacturing tolerances and eliminating the harmful effects of rotational play while maintaining ease of manufacture.

Inventive Principle:
Principle #35Parameter changes

3Ease of operation

If the coupling device allows rotational movement between parts during assembly, then assembly is easier, but rotational play cannot be eliminated during operation

Engineering Contradiction:
Improveassembly easeVSAvoidrotational positioning precision
Core Design Contradiction:
Ease of operationVSManufacturing precision

Solution Approach 1:

The coupling device transitions from a static connection to a dynamic locking mechanism. During assembly, the connection is loose to allow easy positioning. During operation, the tensioning means activates the inclined bearing faces to dynamically lock the rotational position, eliminating play while maintaining assembly ease.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The inclined bearing faces are pre-configured to automatically take up rotational play once axial tension is applied. The geometry is designed in advance so that the moment the tensioning means engages, the rotational locking action occurs automatically, eliminating the need for separate adjustment steps while maintaining manufacturing precision.

Inventive Principle:
Principle #10Preliminary action

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 eliminates rotational play and associated shocks, enhancing the machine's operational smoothness and longevity by ensuring precise immobilization of parts, reducing wear, and improving user experience.

Implementation Method 1

said force keeps said at least one first support face in contact against said at least one second support face so that, in said operational position, the immobilization of said first part with respect to said second part along said axis simultaneously results in immobilization of said first part with respect to said second part around said axis

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 2

during one revolution of said rotor, said second part, subjected in particular to centrifugal acceleration, cannot move relative to said first part at least along said axis

Methodology Applied
Scientific EffectCentrifugal force: Centrifugal Force

Data Source

PatentEP2599376B1Haymaking machine
Publication Date: 2015.10.21 KUHN SA
  • EP2599376B1 patent drawingFigure 1
  • EP2599376B1 patent drawingFigure 2~3
  • EP2599376B1 patent drawingFigure 4~5

AI summary

The machine has a rotor provided with an arm (16) that comprises two portions (24, 25). The portions of the arm are connected together by a coupling device (27), and an abutment (33) comprises two support portions (35, 36) that are attached to the two portions of the arm, respectively. The support portions respectively comprise two support faces (43, 44) that are tilted with respect to an axis (26). The faces are provided in contact with each other such that a relative immobilization of the two portions of the arm along the axis is enabled in an operational position.