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5. Replace separate springs with parts with thin sections that act as springs.
6.When screws are required (often for maintenance) try to reduce the number to a minimum.
7.Cables can be eliminated for a reduction in cost, and an increase in reliability, and access for maintenance. Card edge connectors, and PCBs will be slightly higher in material costs, but the boards are simply plugged together. If cables are strung between boards and other boards/components, they will require additional time for soldering, be the source of soldering quality problems, and make the boards tricky to orient, etc.
DI:13.2.4 Feeding and Orienting Parts
• It must be considered that more complicated parts require greater handling time to properly orient them.
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DI:13.2.4.1 - Part Tangling/Nesting
•It should be considered that when small parts are shipped, they come in bulk lots. (large/more expensive parts are often shipped in pallets, or separately.
•When the parts are stored together, they can sometimes tangle or nest.
Tangling - the parts get looped together, making them difficult to separate Nesting - one part gets stuck inside another, much like styrofoam cups.
•The obvious problem with this situation is that the parts often require additional costly human intervention to separate them, and this problem will greatly reduce the success of an automated parts feeder.
•The problems of nesting and tangling can be significantly reduced through small design modification in many cases.
•A few of the problems, and some possible solutions are shown,
PROBLEM: Two shapes can naturally nest, and in the case, suction and friction will hold them in place. [Iredale, 1964]
SOLUTION: Put a rib or riser in the bottom to stop the two cups from mating.
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PROBLEM: Two split rings can loop over each other, and become tangled. [Iredale, 1964]
SOLUTION: We can’t get rid of the split (it is needed for contraction), but we can remove the large gap between the openings.
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PROBLEM: Two open ended coil springs will tend to get stuck together quite easily. [Iredale, 1964]
SOLUTION: If the ends are closed, then the springs will not be coiled together except when force is applied.
DI:13.2.4.2 - Handling Parts
• As parts vary greatly in size we must how it is to be manipulated. The basic categories are,
CATEGORY |
DESCRIPTION |
One hand with tools |
Very small, or delicate objects will have to be grasped with spe- |
|
cial motion amplifiers, and visual aids. |
One hand |
Parts can be easily picked up with a single hand |
Two Hands |
Parts are light enough for one hand, but a second hand is needed |
|
for untangling, support, etc. |
Two hands/heavy |
Both hands are needed for object bulk and/or mass |
Multiple people |
Two or more workers are required for bulk and/or mass |
Heavy lifting tools |
Equipment such as lift trucks are required to move parts. |