REFERENCES • 2013 SolidWorks Help. Web. 2013.

• Volt Plastics. VOLT catalog 24. September 2009. 107-108. Web.

<http://www.voltplastics.com/pdf/VOLTCatalog24.pdf>

• Amber Plastics. Designers Guide to Rotational Moulding. 1-13. Web.

<http://www.amberplastics.co.uk/UserFiles/File/Rotational_Moulding_Design_Guide.pdf>

REFERENCES

ACKNOLEDGEMENT

Jason Costello & Tony Abrams at Canyon Coolers, Make-it

Manufacturing, Dr. Srinivas Kosaraju, Dr. Brent Nelson, Dr. John

Tester, and Dr. Timothy Becker.

ACKNOLEDGEMENT

Figure 2: Cooler Assembly in the Latched Position

Figure 3: Experimental Data

Figure 4: Current Cooler Data Compared to Simulated Performance of New Model

Engineering Design

DESIGN

All major components of the cooler assembly were designed in SolidWorks software. The assembly

consists of four part files: the lid, body, and two identical latches. All standard components of the cooler will

be acquired from existing manufacturers. All materials required for one unit are covered in the components

section. The body and lid of the cooler were designed for rotational molding, whereas the latch was

designed for injection molding. The CAD files were designed as blueprints for mold manufacturing. Each

mold functions as the hollow container that dictates geometry for the finished product. Outlined objectives,

manufacturability, and aesthetic finish were all carefully considered in each component of the final design.

DESIGN

40 QUART COOLER DESIGN Dirk Prather ~ Dominic Albano ~ Federico Martolini ~ Daniel Miller ~ Bander Almazroua

Department of Mechanical Engineering

Northern Arizona University, Flagstaff, AZ 86011

INTRODUCTION

Canyon Coolers is a small business located in Flagstaff, Arizona

that provides premium ice chests for its customers. The coolers

they sell feature a rotationally molded UV resistant HDPE (high

density polyurethane) shell injected with low thermal conductivity

polyethylene foam. The demand for these products is rapidly

expanding in the American market, creating increased competition

between the numerous distributors. Canyon Coolers is looking to

improve upon its existing designs in order to expand their business

and develop a prominent position in the market.

The challenge presented was to overhaul the existing 40 quart

model that is offered by Canyon Coolers. A number of models in

their current product line suffer from minor defects that result in an

intolerable profit loss. The 40 quart model was selected for

research and development because of its current design concerns

and its high demand in the premium cooler market. The goal of the

new design was to engineer features that accommodate a wide

range of use, while maintaining long term durability and the

competitive price point of the existing design.

INTRODUCTION

• OB

• MSRP of no more than $199.99

• Increased ice retention from existing model

• Body fits inside at least one existing model for shipping

• Dead weight of approximately 20 lbs.

• Well integrated features that resist impact stress

• Air and water tight construction

• Warp resistant in areas of high concern

• Two available lid positions:

• Open flat against a wall surface (secondary)

• Fully open and supported (primary)

• Improved latching mechanism

• Designed optimally for Roto-molding

• High reliability / affordable maintenance

OBJECTIVES

TESTING

Experimental:

For performance purposes,

temperature testing was

conducted on the existing 40 qt.

model. Eight T-type

thermocouples, configured

through a NI 9213 DAQ, were

affixed in strategic positions on

the inside and outside of the

cooler hull. 24 lbs. of ice were

placed inside the cooler initially

and temperature readings were

taken every 10 seconds until all

the ice had reached a liquid

state.

TESTING

Simulation:

SolidWorks Simulation Xpress

was utilized to map common

stress situations in the latch

design. Stress maps were

developed to indicate areas of

intense stress concentration.

The results helped shape the

latch as it progressed through

the design phase. The stress

map for the final design is

depicted in Figure 1.

TESTING

Figure 1: Von Mises Stress Map of Final Latch Design

Secondary Opening Position

• Opens flat against a wall

• Near vertical angle

• Uses friction to maintain angle

• Allows full use of webbing slots

Primary Opening Position

• Allows complete access of contents

• Uses critter-proofing as stopping point

• Integrated hinge with single closed pin

• Warp resistant ear spacing

Hinge Section View

• Details of secondary stop mechanism

• Details of primary stop mechanism

• Lid to body tolerance maintains seal

and provides rigidity

• Large fillet radii ensure consistency

Phantom Latch

• Improvement on existing design

• EPDM UV resistant rubber

• Ergonomic shape

• Easily Replaceable

• Backwards compatible to all existing

Canyon products

Floor Design

• Four insulation injection holes used

also as rubber feet inserts

• Warp resistant reinforcing

• Slide plates reduce stress on feet

and create ease of motion

• Minimizes heat transfer out bottom

Body Lip Features

• Fixed handle

• Dynamic rope handle guide channels

and knot recesses reduce cost

• Tie down webbing slot

• Critter-proofing surrounds lip

reducing chance of infiltration

0

5

10

15

20

25

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5

Tem

pera

ture

(C

)

Time (days)

Temperature of Selected Walls 24 Pounds of Ice

Inside Bottom

Outside Bottom

Inside Back

Outside Back

Inside Side

Outside Side

Inside Top

Outside Top

Ambient

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2

0 0.5 1 1.5 2 2.5 3 3.5 4 4.5

Hea

t T

ran

sfer

(W

)

Time (Days)

Current Model vs. New Design Heat Transfer 24 Pounds of Ice

Current Model Heat Transfer

New Design Heat Transfer

Heat transfer rates for both the existing and the new design are

shown in Figure 4. An analysis of the results from the temperature

experiment and the geometry of the two coolers revealed an

anticipated 29% reduction in theoretical heat transfer. These

results substantiate the predicted performance of the new cooler

design. The final step, reserved for the client, is to take the

proposed designs in to the manufacturing phase.

RESULTS

The results of the thermocouple testing are depicted in Figure 3.

Initially all thermocouples started at the ambient air temperature

until ice was added. At this point the readings from the sensors

recorded a sharp decrease in temperatures. Steady state was

reached at about six hours. This continued until all of the ice had

melted, occurring around the fourth day. These results provided

insight on heat transfer information which was vital to the design.

• COMPONENTS

• Two plastic handles

• Two feet of Nylon rope, ¼" D

• One drain plug

• Two 3/16” trifold Aluminum

rivets

• Two 3/16” Nylon shoulder

washers

• 72” of insulating foam gasket

• COMPONENTS

• Two plastic knobs (latch part)

• Two flat head screws

• Four rubber feet

• 26” steel rod ¼ “ D

• 17.9 lbs. of HDPE plastic

• 2.26 lbs. of Polyurethane

foam

• 0.07 lbs. EPDM rubber

COMPONENTS