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Forces acting on a linearly actuated pin 1

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dlagr21

Mechanical
Apr 12, 2017
5
The site will not let me upload my picture, so hopefully I can explain clearly.

I am going to actuate a pin with a cylinder with a max force of 629N, downward, with a lead angle of 18deg. The pin will then pick up the hole in a cover that weights 14kg, and then pickup an assumed static (it weights 1 ton) hole in a tray, and move the cover into place. The force required to move the cover would be roughly 59N with friction at 0.43, but how do I calculate the force working back up against the pin through the 18deg angle. I did some calculations and came up with a normal force of 167N, but I am second guessing myself. I spoke with a colleague who is good at this stuff and he is also stumped and suggesting using dynamic FEA software to simulate as he cannot come up with an answer either. It is correct to just go back to simple dynamics and use the 18deg, Fn, Fs, Fp based on the cover weight?

Thanks in advance!
 
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It is a JPG named "pin dynamics" and it just gives me an error.
 
Is it "pin dynamics.jpg" or "pin_dynamics.jpeg" or some other variation?
What is the error message?
Did you Browse to the file location or drag and drop?
Did you confirm javascript was enabled? The only failure to upload for me is from not enabling javascript.
Is this from Safari, Chrome, or Firefox? If you are using Chrome see chrome://settings/content/javascript?search=java
 
It is named Pin Dynamics. I browsed to the location, and then selected it. Javascipt is enabled on my chrome browser. It does not tell me what the error is, it just says "error".

But I have created an imgur link here:
 
What is the frictional work to move this? W = F x d = mu x normal force x taper horizontal distance from vertex to o.d. in horizontal plane
What is the cylinder work? W = F x d = Fcyl x taper vertical length

Do some algebra and include actual acceleration kinetic energy changes, if needed, otherwise use a reasonable acceleration force multiplier.

Caution - using the cylinder rod and seals to guide the pin will wear out the seals. You need to guide this thing with some type of linear bearing.
 
Without the ".jpg" or ".jpeg" suffix it cannot know the file type, though your folders likely have common suffixes hiddem.

Probably there is an ad blocker like NoScipt.

One feature missing is the friction between the pin and the cover which will increase the normal force against the table. This will increase the force required and so forth - it will take a few iterations to settle on the value. There will also be some friction with any guide that holds the pin straight which will also participate.

The mechanical ratio is sideways vs. down - the tangent of the slope.
 
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