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Glass Run Channel
What is a Glass Run Channel?
A glass run channel is a seal that enables movable door glass to slide freely
in a confined flocked or coated channel. When in a fully sealed position, the
glass run channel protects the vehicle from the outside environment: water,
dust, and noise pollution. The channel also stabilizes the window during
glass movement, door closing, and vehicle operation. Glass runs are
generally constructed of metal casings, dense rubber or thermoplastic
vulcanizates, and flock, strategically designed to fit the door environment.
Problem Statement
ME 481 Design Projects
Team Members
Wesley Fan
Keith Pigeon
Matt Radley
Chris Stevens
Faculty Advisor
Dr. Koochesfahani
Industrial Advisors
Matthew Ply
Jon Masini
Company Background
General Motors is a large
manufacturing company that
produces many different models of
cars, trucks, and SUV’s. The
company was founded in 1908 and
have been the global industry
sales leader for 76 years. They
currently employ approximately
284,000 people and manufactures
cars and trucks in 33 countries.
Design a low cost glass run channel with superior performance in sealing,
noise, and cost. It should aim to perform better or as effective as the current
GM glass run channel.
Assumptions
Before any modeling of the glass run channel began, a few assumptions had
to be made. First, since automotive seal extrusions have a uniform cross
section, it’s sufficient to analyze the system in 2-D. Also, the type of analysis
would be contact, where the seal sections are deformable and the
environment is a rigid body. Finally, material properties and boundary
conditions are assigned only to the deformable boundaries.
Research
The research for this project consisted of determining which material was
best suited for a new glass run channel. The two materials in question were
thermoplastic vulcanizates, TPV’s, and ethylene propylene diene monomer
rubbers, EPDM. From the beginning of the project, it was known that EPDM
has long dominated the glass-run channel industry. However, through
careful research it was discovered that TPV is slowly becoming the material
of choice in the weather sealing industry for many reasons. These reasons
include: recycling of process scrap and end-products, weight reduction,
better dimensional tolerances, and a simplified manufacturing process.
These qualities were crucial in the decision to choose TPV over EPDM as
they all lead to one important conclusion, a reduced cost of the glass run
channel.
Modeling
•The model used in the finite element analysis was a 2nd order strain energy
potential of polynomial form.
•The equation that represents the material properties for this model is:
FE Analysis Results
Manufacturing Position
Fully Sealed Stress Plots