Forestry Winch Pulley Rope Guide Dynamics

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing forestry winches with upper pulleys experience rope disengagement issues due to the difference in movement axes between the unwinding discs and the wire rope guide, particularly when the guide is facing downwards, leading to potential entanglement and damage.

Innovation Solution

A pulley design featuring a fixed housing with a movable rope guide and an adjustable pushing mechanism that maintains a constant distance with the rope guide, ensuring the rope remains engaged through the use of leading-pushing discs and compression springs, allowing 3D adjustment for reliable guiding.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If fixed unwinding discs are installed on the housing of the upper pulley, then the structure is simple, but the rope may disengage between the unwinding discs and the wire rope guide due to the difference in movement axes

Engineering Contradiction:
Improvepulley structureVSAvoidrope engagement
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent applies the dynamics principle by making the unwinding discs movable rather than fixed. The unwinding discs are mounted on a movable support that can oscillate relative to the housing, allowing them to dynamically adjust their position to track the rope guide's movement. This dynamic adjustment ensures continuous contact between the rope and both the unwinding discs and the rope guide, preventing rope disengagement while maintaining structural simplicity.

Inventive Principle:
Principle #15Dynamics

2Stability of the object's composition

If the wire guide is facing downwards during unwinding, then load pulling stability is improved, but the probability of rope disengagement and entanglement increases

Engineering Contradiction:
Improveload pulling stabilityVSAvoidrope engagement
Core Design Contradiction:
Stability of the object's compositionVSReliability

Solution Approach 1:

When the wire guide faces downwards, the movable support with unwinding discs can still oscillate to maintain proper rope contact. The dynamic adjustment mechanism ensures that even in the downward-facing configuration, the unwinding discs adapt to the rope's path, preventing disengagement and entanglement while preserving the stability benefits of the downward-facing guide.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent applies preliminary anti-action by positioning the movable unwinding discs in advance to counteract the potential rope disengagement that occurs when the guide faces downwards. The oscillating mechanism proactively adjusts the disc positions to prevent the harmful effect of rope disengagement before it can occur, rather than reacting after disengagement happens.

Inventive Principle:
Principle #9Preliminary anti-action

3Productivity

If the rope is damaged or dislocated, then the pulling operation continues, but the wire rope may be damaged or broken or parts of the winch may be damaged

Engineering Contradiction:
Improvepulling operation continuityVSAvoidrope and winch damage
Core Design Contradiction:
ProductivityVSObject-affected harmful factors

Solution Approach 1:

The patent applies feedback by using the movable support with oscillating unwinding discs to continuously monitor and respond to the rope's position. When the rope becomes damaged or dislocated, the dynamic system detects the change in rope path and adjusts accordingly, providing immediate feedback that prevents further damage to the rope and winch components while allowing the pulling operation to continue safely.

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

Prevents rope disengagement from the pulley in all positions, enhancing stability and reducing the risk of entanglement or damage during load pulling, especially when the rope guide is facing downwards.

Implementation Method 1

The housing (holder) of the leading-pushing cylinders is preferably with screws, but also in any other manner, adjustably mounted on the housing of the rope guide. At the same time, at least one compression spring, preferably two or more compression springs, exert pressure of the leading-pushing discs on the driven sheave.

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP4194389B1A pulley with improved guiding of a rope and a winch with said pulley
Publication Date: 2024.05.22 PISEK - VITLI KRPAN D O O
  • EP4194389B1 patent drawingFigure 1a
  • EP4194389B1 patent drawingFigure 1b
  • EP4194389B1 patent drawingFigure 2

AI summary

The present invention belongs to the field of forestry winches, more precisely to the field of constructional details of winches, particularly related to the upper pulley with an unwinding device. The invention relates to a pulley with improved guiding of a rope and a winch with said pulley that comprises: - a housing (11), which is in a vertical axis (11a) rotatably mountable on a housing of a winch, - a movable guide (12) of the rope (2), said guide (12) movable mounted in the fixed housing (11) around a sheave (13) rotation axis, - the sheave (13) along which the rope (2) runs, and - a pushing mechanism (14) arranged to lead the rope (2), said mechanism (14) is mounted on the movable rope guide (12), so that the pushing mechanism (14) is synchronously movable with the rope guide (12) and the distance between the pushing mechanism (14) and the rope guide (12) is constant regardless of the horizontal position of the rope guide (12).