proportional valve mechanism

[Konstantin Bogach]

I don't have much resonse on my question about proportional valve rod
(or pin) length of travel. So, I am trying to ask different question.
Does the valve change the pressure (really)  proportionally to load or
it has just on/off states (for example, on 1:1, off 5:1 ).  Again, the
rod travels only 1mm  and I don't believe it is right.  But if it on/off
switch then it might be ok.  Frankly speaking, I don't believe it works
lke switch but, from other hand, I don' t see how it can seize. There is
no rust inside. Unless something is dislodged inside...  Any BTDTs?

Konstantin Bogach.