An elavator is a moving cabin that gravity acts on. On the scales of the typical elevator application (a skyscraper for example), gravity is constant. So the gravitational force can be counteracted by a counterweight, and the whole elevator can be moved with comparably little force.
Is there a similar thing to counteract the force that a spring exerts? The inherent problem I see here is that springs have a position dependent force (with a negative proportionality constant), that needs to be counteracted with a position dependent force with a positive proportionality constant: To illustrate what I mean, I appended two figures:
In the first image, we can see what happens if I simply connect two springs whose equilibrium position are displaced from each other. The result is the displacement - force dependence of another spring, that simply has a bigger spring constant, and an equilibrium position between the two beforementioned springs.
Picture two shows the possible effect of the fictious element that I'm looking for, which flattens the resulting overall force curve. The combined system then still has an equilibrium position that it tends to, but the force needed to displace the system from that position are mutch smaller.
Some notes for clarification, as mechanical systems can be abitrarily complex, and some comments pointed out that the question is unclear:
The combined system of the spring and device X that I'm looking for should again have 1 degree of freedom. Displacements in this degree of freedom should result in the same displacement of the spring: There should not be any leverage. Displacing this degree of freedom should however require "less" force in some working range. Here, by "less" it is meant that the magnitude of the force is smaller than highest force in the working range of the original spring. The new combined system may or may not have a new equilibrium position. In case there is one, the force per displacement to displace the system out of that position should be smaller.
Is there such a device? Or a whole class of such devices?
To give context: I'd like to build a (Geigenwerk), and it requires the force of the player to lift the strings off the bowing wheels. Displacing the strings, they behave like a spring, and to ease the players efforts, the force needed to displace them has to be diminished. Leverage is not an option, as in that case the player will need to displace the keys more, and thus the instrument as a whole will be less responsive.