Mechanical constraint

Hi all
I tried to use rack and pinion mechanism in design
I use rack and pinion constraint, select pitch line of rack and pitch dia circle of gear for constrain
constraint added but if I drag rack it moves in linear direction no gear movement
if I drag gear it rotate no rack movement
normal constraint added gear has only rotate freedom and rack moves only linear direction
what is the meaning of revolution/Distance or distance/revolution?
what value should be write in next column?
Please guide me with example

Hi PDPatel,

I am pretty sure that in your try, if you attempt to infinitly rotate the wheel, you would eventually start to notice slight RACK movement. Then you can start to grasp what is happening (did it myself ^^).

From my understanding, the value you have to enter is:
how much you want part A to move, if you move part B by a unit of dimension

If you have a wheel of pitch diameter = 100, if it does 1 full rotation, you would want the rack to translate by (100*π).
You would divide, the other way around (you slide RACK first, then observe PINION rotation).

As a “UNIT of dimension”, I guess you would use either the nominal diameter of the wheel, or the tooths’ step(interval?).


Part001.Z3 (1.6 MB)

Hi Nicolas_TR
I understand it, now its works fine
Thanks for detailed replay with example

Hi PD, I agree with Nicolas.
Normally rotation is in radians . Pi radians per rev.
Mathematical relationship is more reliable than inferred solution from geometry.
Good to see a happy outcome.