Chain Assembly
1.
Create
an extra part where the relationship between the parts
can be stored
(Mating)
Sketch the
chain path and outer limit
Make them selectable objects with Ableiten & Parallel Curve
2.
Bring in Chain link
2xKongruenz
3.
DMU Kinematics
Fix sketch to create mechanism
2xPunktkurvenverbindung
1xGleitkurveverbindung
4.
Bring in 2
nd
link element
2xKongruenz
5.
Change to DMU Kinematics
Insert Revolute Joint between Links
Insert Punktkurvenverbindung
6.
Repeat step 4 & 5
… It may
take a while
Then add the turning of the gears to the Mechanism
:
1.
Draw
the
centre axis of both gears in the
part
“Mating”
2.
Use the
se
axes in DMU Kinematics to create 2 Drehverbindungen
3.
Create a Zahnradverbindung
Find the two required Drehverbindugen from
the
Mechanism Verbindungen
And tick the box
“Abhänginger Winkel fr die Drehverbindung 1 or 2”
Don’t forget the Gear Ratio!
Now to match the Gear to the chain
First go back to the “Mating” Part and draw a
line that is 45⁰ to the coordinate system of the gear.
The gear should be the one that has the “Abhängiger Winkel
für die Drehverbindung” from earlier
Now connect this to the Befehle by right clicking on each
Befehle and selecting “Object Befehle …

Defin
ition”. Then
click on Verknüpfen and select the line
. Do this for both
Befehlen
(it will become clear why later)
The mechanism can now be simulated with both the chain and gears moving together using the
“Simulation mit Regeln” Button.
It is located besi
de the Simulation mit Befehlen button
You will notice that the gear speed and the chain speed don’t match. To fix this, right click on the Go
to the Befehle in the Mechanism. There should be two. One for the Chain movement and one for the
rotation. If y
ou check the definition of each Befehle and look at the formula
you will notice that
the formula for rotation is multiplied by 1deg and the one for linear motion of the chain is multiplied
by 1mm. Therefore 1degree of
rotation of the driving gear is take
n as
equivilant to 1mm of motion of the
chain. We know this is however not
the case and in order to find the
correct value, Use the earlier sketch in
“Mating” of the diameter of the
centre of the chain path (what you
you have been telling the middle of
the
chain links to be Kongruent to),
take a 1degree arc of this circle and
measure the absolute distance
between the start and finish of this arc.
In this case it was 0,325mm. Enter this value into the formula from earlier
(Above). Make sure that you change
0,325mm to 0.325mm!
Now the teeth and chain run at the correct speed but they don’t mesh
properly. To fix this simply measure by how much the teeth are out
and
add this value to the formula with + or

. Then Finished!!
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