Step 1: Perform a
tolerance study of your worst-case assembly misalignment.
a.) Tolerance to which your assembly machine
can position Part A.
b.) Tolerance to which your feeder can position Part B.
c.) Repeatability of tooling handling Part A.
d.) Locational tolerance of Part B's feature (e.g.: hole)
e.) Repeatability of Compensator is +/- 0.002" in the vertical position.
Assembly Misalignment (worst case) = a)
+ b) + c) + d) + e)
Step 2: Find your
total clearance.
a.) Chamfer size on Part A (a lead in is
required on at least one part)
b.) Chamfer size on Part B.
c.) Worst case part clearance, Y subtract X.
Total Clearance = a) + b) + c)
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The Compensator is needed when the assembly
misalignment is greater than the part clearance.
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The total clearance must be greater than the
assembly misalignment or two parallel surfaces will contact. If the total
clearance is less than the assembly misalignment, then increase the chamfer
size on Part A and/or Part B.
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Select a Compensator with allowable misalignment
greater than the assembly misalignment.
When the insertion axis is not vertical, the initial
offset of the Compensator due to the weight of the tooling and part must be
taken into consideration as there is some lateral and cocking deflection of the
flexing shear pads. This reduces the allowable misalignment in the
downward direction, while increasing it in the upward direction.
