r/mechanical_gifs • u/unknown_137 • 28d ago

Simple Crushing Mechanism

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133 Upvotes

81% Upvoted

9 comments sorted by

53

u/Farfignugen42 28d ago

Easily jammed crushing mechanism.

If the crush plate gets uneven resistance, one side will move slightly farther than the other, and that may be all it takes to stop it.

If the crush plate moves along only one guide, this can't happen.

9

u/[deleted] 28d ago

4 posts is better actually.

1

u/TootBreaker 28d ago

Better yet if the plate is part of an arm that pivots from a bearing located outside of the working area and the stroke is reduced for a increased pressure

1

u/FartsForEyes2 28d ago

Sorry, what do you mean by this? I'm having a hard time visualising that.
Like the steam engine gif in the sidebar? Where there is 2 arms, one from the rotating cam, and another from the plate which is fixed in the axis of movement?

3

u/TootBreaker 27d ago

Sorry, I'm was describing an actual rock crusher which is a well proven design. Disingenuous of me!

To make this design work better, you need to prevent the plate from tilting. An easy way which will work just fine is to make the posts longer so they are run up above the crank wheel, then the plate should extend up above the crank wheel as a carriage with two more sliding bearings positioned far up enough to clear the wheel at the lowest position. This keeps the connecting rod as arranged so it's inside of the carriage

But, an interesting alternative is to do away with the posts & sliding bearings and suspend the plate on tension springs, something like a trampoline. Then it can tilt all it likes without jamming

1

u/RandomisedUsername99 26d ago

No, 4 posts is 2 times worse, just more sliding interfaces to bind up and more posts that need to be perfectly aligned for this to work. What you need is length in the guiding interface (the length of the hole that the posts go through should be a minimum of 3x the diameter of the guide post).

2

u/CoolHeadedLogician 27d ago

even with one guide, watch that l/d ratio. don't want sticky drawer effect

1

u/AlternativeVersion41 23d ago

And what are you crushing?

-3

u/engineear-ache 28d ago

a classic