Granulator Mill Scraping Device Prevents Rotor Wedging

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Granulated plastic chips tend to wedge between the rotatable rotor and static housing in granulator mills, causing friction, overheating, and the formation of disintegrated plastic threads during the recycling process, which restricts rotor rotation and affects the quality of the final granulate.

Innovation Solution

A granulator mill design featuring a scraping device attached to the housing that extends radially towards the outer circumference of the granule chamber, guiding granulated waste away from the axial space between the rotor and housing, preventing chips from getting stuck and ensuring smooth rotor rotation, while also preventing the transformation of plastic chips into disintegrated threads.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If granulated plastic chips are produced in the granulator mill, then plastic waste is successfully recycled into reusable granulate, but the chips tend to wedge between the rotatable rotor and static housing causing friction and overheating

Engineering Contradiction:

Improveplastic waste recycling efficiencyVSAvoidrotor rotation smoothness

Core Design Contradiction:

ProductivityVSReliability

Solution Approach 1:

A scraping device is introduced as an intermediary element between the rotor and housing. This scraper extends radially into the axial space and actively removes granulated chips before they can wedge between the rotating rotor and static housing, thereby preventing friction and overheating while maintaining continuous operation

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The scraping device extracts granulated chips from the axial space between rotor and housing before they can cause problems. By continuously removing these chips through the radial scraping action, the system prevents wedge formation and maintains reliable rotor rotation throughout the recycling process

Inventive Principle:

Principle #2Taking out (Extraction)

2Productivity

If the rotor rotates at high speed to improve granulation efficiency, then productivity increases, but friction heat causes plastic chips to melt and transform into disintegrated threads

Engineering Contradiction:

Improvegranulation speedVSAvoidgranulate quality

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

The scraping device acts as a heat management intermediary by removing chips from the high-friction zone before they accumulate enough heat to melt. This prevents the transformation of granulated chips into disintegrated threads and maintains granulate quality even during high-speed operation

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The scraping device converts the potentially harmful friction heat into a beneficial cleaning action. By scraping chips away from the rotor-housing interface, it prevents overheating and maintains chip integrity, turning the friction problem into an opportunity for continuous chip removal and quality control

Inventive Principle:

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

3Reliability

If the axial space between rotor and housing is reduced to minimize chip wedging, then chip entrapment decreases, but the rotor rotation is restricted and friction increases

Engineering Contradiction:

Improvechip wedging preventionVSAvoidrotor housing clearance design

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The scraping device introduces an active management element that allows the axial space to remain sufficiently large for free rotor rotation. The scraper continuously removes chips from this space, preventing wedging without requiring tight tolerances or complex clearance designs between rotor and housing

Inventive Principle:

Principle #24Intermediary (Mediator)

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

The scraping device effectively prevents plastic chips from wedging between the rotor and housing, maintaining rotor speed and preventing the formation of disintegrated threads, thus enhancing the efficiency and quality of the granulation process.

Implementation Method 1

the larger friction force is exerted between the rotor and the static housing and this leads to heated plastic chips

Methodology Applied

Scientific EffectFriction: Friction

Implementation Method 2

the larger friction force is exerted between the rotor and the static housing and this leads to heated plastic chips which may get sticky

Methodology Applied

Scientific EffectHeating: Heating

Implementation Method 3

the solid plastic of the chip may melt and transform into disintegrated plastic threads during the rotation of the rotor

Methodology Applied

Scientific EffectMelting: Melting

Data Source

PatentUS11273450B2Granulator mill

Publication Date: 2022.03.15 RAPID GRANULATOR

AI summary

Granulator mill granule chamber including at least one non-rotatable blade, rotatable rotor arranged inside the granule chamber, the rotor a number of blades which are arranged for cooperation with the non-rotatable blade, a infeed hopper for feeding waste into the granule chamber, a grid arranged in the granule chamber, where through granulated waste is allowed to pass to an outfeed hopper. A scraping device is provided in a space located axially in between a housing and the rotatable rotor and the scraping device is attached to the housing.