Fixed Pulley Centres


Fixed Pulley Centres

This means the centre of each pulley does not move in the relative to the machine frame [Base-Part]


We add the sketch for the belt path to the Base-Part.
Each Pulley is a rotating-Part joined to the Base-Part with a Pin-Joint.

A Pulley Part can be a:

Drive Pulley
The Drive Pulley is kinematically-defined with a motion before you use Add Pulley.
The Drive Pulley rotates to move the Belt.

Linear Motion of Belt =

Drive Pulley Radius x Drive Pulley Angular Motion

Driven Pulley
The Driven Pulley becomes kinematically-defined by Add Pulley.
The Driven Pulley is rotated by the Belt.

Angular Motion of Pulley =

Linear Motion of Belt / Pulley Radius.

Pulleys that have 'Fixed-Centres' rotate with their centres fixed to the Base-Part.

It is possible to have:


When Pulleys have Fixed Centres, the:


Pulleys are Rotating-Parts, with Pin-Joints at the centre-Points of the Arcs in the sketch-loop in the Base-Part
Use the Pulley dialog-box to edit the Number-of-Teeth of each with the


The 'Belt' is a sketch-loop
When the Pulleys are on fixed-centres, add the sketch-loop to the Base-Part


The Pulleys or the Belt move with a specified motion.

When the motion is specified for the:

Belt: We use a Motion-Path FB to define the motion of a Motion-Point along the sketch-loop on the Base-Part. Then, the Pulley's motion comes from the Belt's motion.
Pulley. We use a Motion-Dimension FB to define the rotation of the Pulley.  Then, the Belt's motion comes from the Pulley's motion.

To be a Drive Pulley, the Part must be kinematically-defined before you apply to it the Add Pulley command.




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