Oil pump piston, some questions.

[Homeoboxter]

[QUOTE=The Radium King;657185]

note the bit where they say "It’s important to point out that preload doesn’t affect spring stiffness."

[/QUOTE

Thanks for the article, it got me thinking. It also says this: The more preload, the harder the suspension is.

But how can the suspension be harder if the same force is required to further compress the spring?

I think they mean by stiffness is the spring constant, which does not change. However, when you pre-load the spring, you increase the potential energy in it, which competes against you when you further compress the spring.

Take a look at this forc vs. displacement relatainship on a linear spring:


It's from here:
https://www.sciencebuddies.org/science-fair-projects/references/linear-nonlinear-springs-tutorial

The more force the more displacement, which also means to me that if you displace your spring from 0.2 to 0.3 requires more force than if you compress it from 0.1 to 0.2. Similarly, if you take a valve spring for instance, and you compress it 10%, it is easier than if you compress it from 10% to 20%.

Progressive springs are the same, just this equation above is supralinear.

That's my understanding. I'm not a physisist though .