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Mate to use for a Cam
ShepRCS
Member Posts: 9 ✭
Hi All
I've built Combers Rotary engine which uses a Cam to create rotary motion. It appears circular although it is not quite.
I don't think that there is a Mate/Relation I can apply that will make the engine actually work when I spin the shaft? It would be a mate between the bearing and the cam ring or a relation between the piston and the model like a rack and pinion but it needs to go up for 180deg and down for the rest. Anyone with any ideas on this?
Here is a link to the model I hope (just copied the address bar from the model which I have made public)
Shep
I've built Combers Rotary engine which uses a Cam to create rotary motion. It appears circular although it is not quite.
I don't think that there is a Mate/Relation I can apply that will make the engine actually work when I spin the shaft? It would be a mate between the bearing and the cam ring or a relation between the piston and the model like a rack and pinion but it needs to go up for 180deg and down for the rest. Anyone with any ideas on this?
Here is a link to the model I hope (just copied the address bar from the model which I have made public)
Shep
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Best Answer
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Optionsandrew_troup
Member, Mentor Posts: 1,584 ✭✭✭✭✭
@Shep
Here's a recent post on another thread which will hopefully answer your questions
Andrew_Troup said:@Hansrudolf : You can certainly model a cam as a part very nicely in OnS. What the contributors are saying above is that (at present) there is no OnS way (or at least, no intended way) to have a non-circular cam activate a follower realistically, as it spins in an assembly model of a mechanism.
In other packages (and presumably in OnS at some future date) there is a "cam mate" which allows creating a tangent mate with a path. In some cases, the path is limited to arcs and lines, in others it can be spline-based.
An option OnS might perhaps consider, if they implement a "Fit Spline" solution (which can convert chains of arcs and lines to a single spline) would be to simplify the input options to a cam mate by accepting only splines - preferably open splines, as well as closed ones.6
Answers
Here's a recent post on another thread which will hopefully answer your questions
Andrew_Troup said:@Hansrudolf : You can certainly model a cam as a part very nicely in OnS. What the contributors are saying above is that (at present) there is no OnS way (or at least, no intended way) to have a non-circular cam activate a follower realistically, as it spins in an assembly model of a mechanism.
In other packages (and presumably in OnS at some future date) there is a "cam mate" which allows creating a tangent mate with a path. In some cases, the path is limited to arcs and lines, in others it can be spline-based.
An option OnS might perhaps consider, if they implement a "Fit Spline" solution (which can convert chains of arcs and lines to a single spline) would be to simplify the input options to a cam mate by accepting only splines - preferably open splines, as well as closed ones.
Waiting on Cam Mate then!
Shep
There is a post in the Improvement Request section for completion of the Mates Suite, including Cam. Head on over there and vote it up!