Change in Positioning/ Fastening Direction |
Change in positioning direction becomes necessary, within a positioning process, if a component or sub-assembly has to be positioned in more than one direction along a defined positioning axis. Change in fastening direction exists if a component or sub-assembly has to be fastened in more than one fastening axis/direction at the destination. |
Explanation
The aim should be to position and fasten all components or assemblies in only one direction. This requires defining a coordinate system for the positioning direction in order to illustrate the defined positioning axis and positioning or fastening directions. If a component needs to be rotated or turned for further assembly, this is evaluated by changing the positioning or fastening direction.
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Defining a coordinate system |
Change in positioning direction |
Rule M-R1: |
In case of a change of the coordinate axis back to the specified main assembly direction, this is not evaluated. |
Example 1: Changing of positioning and fastening direction
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Adding a coordinate system |
The z-axis is the main assembly direction from top to bottom |
Change in axis |
Change in direction |
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z-axis |
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4 bolts (assembly position) |
0 |
0 |
from z-axis to y-axis |
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2 bolts (left side) |
2 |
0 |
Change in direction on y-axis |
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2 bolts (right side) |
0 |
2 |
from y-axis to x-axis |
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1 bolt |
1 |
0 |
Example 2: Assemble a switch cover to an oven with 3 bolts in a defined assembly order.
In order to fasten the 1st bolt, a change of the axis (X -> Y), and for the 2nd bolt, a change in positioning direction (+Y -> -Y), has to be evaluated.
Note: |
A change in the joining or fastening direction may result in an unfavorable position of the wrist, elbow, and/or shoulder joint. The assembly difficulty is therefore taken into account in the ergonomic risk evaluation for the upper limbs. |