Coreless Polymer Film Roll Removal via Air-Water Mixture
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for removing coreless plastic film rolls from a spindle result in high power consumption and complex processes due to the need for high compressed air flow rates and intricate spindle surface treatments, which increase friction and operational difficulties.
Innovation Solution
The method involves using a pressurized air-water mixture through the perforated spindle wall to expand the roll's inner diameter, reducing friction and power consumption by transitioning from 'dry' to 'wet' sliding friction, and employing a mechanical pusher for roll removal, with adjustable air-water mixture pressure based on roll density and film deformation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If high compressed air flow rate is used to reduce friction between the roll and spindle, then the roll can be removed from the spindle, but power consumption increases
Solution Approach 1:
A water film is introduced as an intermediary substance between the roll and spindle surfaces. The water reduces the coefficient of sliding friction by transitioning from dry friction to wet friction, allowing the roll to be removed with significantly lower compressed air flow rates and thus reducing power consumption
Solution Approach 2:
The physical state of the interface between roll and spindle is changed by introducing water, transforming the friction condition from dry to wet. This parameter change in the interface condition enables effective roll removal with reduced energy input
2Ease of operation
If compressed air is used to expand the roll inner diameter for removal, then the roll can be pushed from the spindle, but the process becomes complex with intricate spindle surface treatments required
Solution Approach 1:
Water serves as a mediator that simplifies the spindle surface requirements. Instead of requiring complex surface treatments like sandblasting or protective coatings, the water film provides the necessary lubrication, reducing the spindle surface preparation to basic perforation only
Solution Approach 2:
The complex spindle surface treatment requirements are extracted and removed from the system. The invention eliminates the need for sandblasting, protective coatings, or intricate surface geometries by replacing them with the simpler water film mechanism
3Ease of operation
If high compressed air flow rate is maintained throughout the winding cycle, then friction is reduced, but power consumption increases significantly
Solution Approach 1:
The water film application is implemented as a periodic action rather than continuous compressed air flow. Water is applied at specific moments (during roll formation and removal), allowing the system to maintain low friction conditions without the continuous energy input required by traditional compressed air methods
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 approach significantly reduces power consumption, increases removal speed, and simplifies the process by minimizing spindle surface treatment requirements while effectively reducing friction and electrostatic effects, enhancing safety and operational efficiency.
Implementation Method 1
causing a radial expansion of internal turns of the roll; causing an expansion of some internal turns of the roll by feeding a compressed air flow through the air-chamber of the perforated wall of the spindle
Implementation Method 2
sliding friction produced between the internal surface of the roll and the material of the spindle can be reduced with a specific sliding coating of the spindle surface; reduction of friction between the internal roll surface and the spindle surface
Data Source
Figure 1
AI summary
A technical solution proposed herein relates to rewinding of plastic film out of big rolls to smaller ones, suitable for wrapping different goods and loads, wherein the film is wounded in a roll without a spool directly onto the spindle of the rewinding unit, and may be applied in manual and automated wrapping machines. A method of plastic film coreless roll removal from a spindle, comprising pushing of the plastic film coreless roll from the spindle with a perforated wall, where pressurized air-water mixture is fed at pushing the roll, providing expansion of the inner diameter of the roll. The object of the claimed technical solution is to provide technical results, consisting in reduction of power consumption by decrease of compressed air flow rate, with simultaneous increase of speed and safekeeping of the roll at its removal from the spindle by reduction of friction between the internal roll surface and the spindle surface. 1 independent claim, 2 dependent claims, 1 figure.