DFMA as Applied to the Swingline 747 Desktop ... - University of Utah

17. Plastic Cover
Fig 20 Plastic Cover
DFMA as Applied to the Swingline ® 747 Desktop Stapler
The plastic cover mainly serves as an advertising plate for Swingline ® . It also covers the
holes in the upper cover.
2 DFMA Paradigms and Analyses
What follows is the discussion of DFMA paradigms and their application to three
areas; material selection, manufacturing, and assembly. In each area, the general
paradigms will be followed by their application to specific parts of the product.
2.1 Material Selection – General Paradigms
There are several factors which bear consideration while designing a product.
Among these are weight, strength, cost, durability, environment, aesthetics, etc. Each one
of these can affect the design both from the manufacture and assembly aspects. A part
that is designed for optimum manufacturability with a specific material may give rise to
assembly issues. The converse is also true. While still in the design phase, giving
thought to these factors will help reduce problems in the subsequent stages. With respect
to the mass of the material, and therefore the weight, some thoughts might go to whether
the product needs to be portable, if it will be manufactured on-site, what loads will be
placed on it, what are the costs involved, and so forth. Strength of the material selected is
also important primarily to prevent failure of the design. Figure 21 shows the stress-
strain plots for various materials. A DFMA analysis of a part might yield wood as the
best possible choice when considering cost and ease of manufacturability, as was the case
with one component of the stapler. However, functional analysis would identify that
material to be inadequate as it would fail under normal operating conditions. Figure 22
describes several general trends in relation to strength of materials.
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