Hello folks.
TL;DR: My question is: is there a way of generating gears, in such a way that the pitch diameters are linked to cylinder diameters?
if not, is there any way to define the pitch diameters or gear ratio in a way that can be linked to part geometry?
I am using gear generator for the first time.
I understand how I can add gear teeth to my parts, but the way I have managed it doesn't seem future-proof, so I think I may be missing something. By the way I'm working with Inventor 2020.2.
The way I have done my model is to create an assembly of cylinders, where each cylinder is the diameter of the desired gear pitch diameter. The centres of the cylinders are constrained in position.
Since I have defined the centres and pitch diameters of the gears, I would have thought this would be enough information for the gear generator tool to be able to create gear designs. But instead I'm prompted to manually enter the desired gear ratio (this should be the ratio of the two cylinder diameters). To make things worse, I can't seem to make the gear ratio value linked to any other parameters, so I can't set it to be equal to the ratio between the cylinder diameters.
I want the gear ratio to be defined by the cylinder parts, because the gear ratios in the mechanism are dependent on other geometry, so if I change one part, I need the gear ratios to update accordingly.
Something else I noticed is that the gear generator features only remove material from the cylinders, and don't add material, so if my cylinders are the diameter of the gear pitch diameter, I won't get the ends of the teeth. instead the teeth will be truncated / shorter than required. A workaround I used is to increase the diameters of the cylinders, but this just seems a bit unnecessary. I do understant where this would be preferable behaviour, but is there no way of changing this for cases like mine?
I really appreciate any help as I am using this for the first time, and for a personal project. I am beginning to think that defining gears from pitch-diameter-cylinders is not the normal way of operating, but I thought that was a very intuitive way of doing it so it's quite surprising to me if that's the case.
Here are a few pictures to help explain my situation:
my master sketch (I'm using top-down modelling) - I want gear pitch diameters to be defined by the cylinder diameters defined here:
my multibody master part:
my assembly (parts are derived from the master part bodies):
also here's a video of the working simulation
trying to define the gears, but the gear ratio has to be defined again:
linked gear ratio parameter not allowed:
gear teeth being truncated because they are being fit to the part diameters (which are the pitch diameters)
desired result (but it should be parametrically linked to the cylinder geometry):
