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 sub-assemblies in only one direction. This requires defining a coordinate system relative to the positioning direction in order to illustrate the main assembly direction and a positioning or fastening direction. If a component has to be rotated or turned over for the further assembly, this is being evaluated with a change in 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 |
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Change in axis |
Change in direction |
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.
Please 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. |