Adjustable Heat Shrink Tunnel Side Walls for Load-Specific Thermal Efficiency
Solution Overview
Problem
Conventional shrink wrap tunnels experience inefficiencies due to fixed widths, leading to thermal losses and inefficiencies when handling loads of varying sizes, as the heating elements are not optimally positioned relative to the load, resulting in longer warm-up times and increased energy usage.
Innovation Solution
A heat shrink tunnel with adjustable side walls and a heater/blower assembly that can be moved to closely fit the load, minimizing heat loss by directing hot air directly into the wrapped load and drawing it out efficiently, using a telescopic shaft system and cross-flow blower for optimal air distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the tunnel width is fixed and larger than the load width, then the tunnel can accommodate various load sizes, but thermal losses increase due to convective losses in the larger space
Solution Approach 1:
The side walls of the tunnel are made movable rather than fixed, allowing the tunnel width to be dynamically adjusted to match the load width. This eliminates the need for a permanently larger tunnel and reduces thermal losses by minimizing the air space between the load and tunnel walls.
Solution Approach 2:
The tunnel cross-sectional area is made non-uniform by moving the side walls, creating a localized fit around the load. The tunnel width is reduced in the region where the load is present, while other areas can be adjusted as needed, optimizing the thermal efficiency in the critical heating zone.
2Device complexity
If the heating elements are mounted on stationary walls, then the structure is simple, but the heating efficiency decreases when the load width varies
Solution Approach 1:
The side walls with mounted heating elements are made movable, allowing the heating elements to dynamically adjust their position relative to the load. This maintains simple mounting on the wall structure while enabling the heating elements to be optimally positioned for different load widths, improving heating efficiency.
3Adaptability or versatility
If the tunnel is larger than the load, then the tunnel can handle various load widths, but the warm-up time increases due to larger thermal mass and heat losses
Solution Approach 1:
The movable side walls allow the tunnel to be configured to match the actual load dimensions before heating begins. This reduces the effective thermal mass that needs to be heated and minimizes heat losses during warm-up, thereby reducing the warm-up time while maintaining versatility for different load sizes.
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 configuration reduces warm-up times, cycle times, and energy usage by ensuring heaters/blower assemblies are positioned closest to the load, minimizing heat loss and optimizing air flow, thus improving the efficiency of the shrink wrapping process.
Implementation Method 1
heat, typically applied by forced air heaters, is blown over the wrapped load
Implementation Method 2
there are thermal losses and inefficiencies due to convective losses
Implementation Method 3
The telescopic shafts have a thread on opposing ends thereof that cooperate with receivers mounted to the side wall assemblies. The threads are opposite-hand threads from one another and cooperate with receivers mounted to the side wall assemblies. In such an embodiment rotation of the threaded shaft moves the receivers and their respective side wall assemblies receivers in opposite directions toward and away from one another.
Implementation Method 4
Bevel gears positioned at and end of each of the telescopic shafts and bevel gears positioned on the drive shaft cooperate with to rotate the telescopic shafts in conjunction with one another.
Data Source
AI summary
A heat shrink tunnel with width adjustment includes a pair of opposing side wall assemblies, each including an outer wall and an inner perforated wall defining a plenum therebetween. The opposing side walls define a product path with the side wall assemblies being movable toward and away from each other. A heater/blower assembly disposed in each of the opposing side walls and has an outlet directed into the product path. A shroud extends over the side wall assemblies and an open top space between the side all assemblies. The side wall assemblies extend upwardly toward an inside of the shroud so as to define a small gap between tops of the side wall assemblies and the inside of the shroud. The shroud has a bottom wall. A conveyor is configured to convey items through the heat shrink tunnel. A tunnel includes a side wall assembly width adjusting assembly to move the side walls toward and away from one another by actuation of a single actuator.