I am really new at the COSMOSWorks thing and have never hadformal training. Regardless, I am trying desperately to useCOSMOSWorks to validate the design of a plastic knob insert. I amrunning SW SP05. The 2 key things I am trying to accomplish are:
1. Verify that the forces from the crush ribs and flaps in the Xand Y direction=0. This is critical for the knob to remainconcentric to the potentiometer shaft.
-I have tried to fix the outside of the knob and the flatsurface of the pot shaft and add shrink fit contact sets. I thenran the analysis and tried to see if the stress on the shaft wasequal, which would indicate equal forces form the ribs/flaps. Thisalmost seemed to work, but the stresses on the flat side of theshaft never seemed right. And I'm not sure this is the best way toaccomplish this. Is there another way to do this? Perhaps withe thecorrect restraints I could find the displacement and measure thedistance from the axis or the knob insert and pot shaft.
2. Determine the proper interference to acheive a pull force of ~5kg
-I likewise am using the shrink fit contact sets and have triedadding a force to the bottom of the knob. Although this doesn'ttell me anything but that the knob does in fact slide off! I havetried listing the result force>contact/friction force andselecting the faces that I used in the shrink fit contact set, butthe value for the friction force is extreemly high. Not to mentionit is really annoying to use this tool because it is not a standardresult that is saved, maybe I'm using it wrong.
I am also aware that ABS may not fall under the criteria of alinear elastic material, but I also cannot find how to run anon-linear study as shown in the help file. Is it part ofCOSMOSWorks or another tool? For what I'm doing this may be anacceptable assumption..? As of now, no one here has gone throughthis trouble and the knobs end up needing to be tweaked to get theconcentricity and pull force correct, often with a compromise. Ihope to get this working, my paper calculations have a lot ofassumptions and only get me so close. Any help would be greatlyappreciated!
SolidworksSimulation
1. Verify that the forces from the crush ribs and flaps in the Xand Y direction=0. This is critical for the knob to remainconcentric to the potentiometer shaft.
-I have tried to fix the outside of the knob and the flatsurface of the pot shaft and add shrink fit contact sets. I thenran the analysis and tried to see if the stress on the shaft wasequal, which would indicate equal forces form the ribs/flaps. Thisalmost seemed to work, but the stresses on the flat side of theshaft never seemed right. And I'm not sure this is the best way toaccomplish this. Is there another way to do this? Perhaps withe thecorrect restraints I could find the displacement and measure thedistance from the axis or the knob insert and pot shaft.
2. Determine the proper interference to acheive a pull force of ~5kg
-I likewise am using the shrink fit contact sets and have triedadding a force to the bottom of the knob. Although this doesn'ttell me anything but that the knob does in fact slide off! I havetried listing the result force>contact/friction force andselecting the faces that I used in the shrink fit contact set, butthe value for the friction force is extreemly high. Not to mentionit is really annoying to use this tool because it is not a standardresult that is saved, maybe I'm using it wrong.
I am also aware that ABS may not fall under the criteria of alinear elastic material, but I also cannot find how to run anon-linear study as shown in the help file. Is it part ofCOSMOSWorks or another tool? For what I'm doing this may be anacceptable assumption..? As of now, no one here has gone throughthis trouble and the knobs end up needing to be tweaked to get theconcentricity and pull force correct, often with a compromise. Ihope to get this working, my paper calculations have a lot ofassumptions and only get me so close. Any help would be greatlyappreciated!
SolidworksSimulation
