Option 2: Orbiting Pulley center

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Option 2: Orbiting Pulley center

Option 2: Orbiting Pulley center

GST-OrbitingPulleys

Orbiting Gear center: There is one fixed Pulley, joined to the Base-Part.

The belt path is moves with a rotating Part. The Orbiting Pulleys rotate with a rotating Part around the center of one fixed Pulley on a rotating Part.

Each Part can be:

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

Linear Motion of Belt = Driving-Pulley Radius x Driving-Pulley Angular Motion

•Driven-Pulley
The Driven-Pulley becomes kinematically-defined by Add Pulley.
The Belt moves to rotate the Driven-Pulley.

Angular Motion of Pulley = Linear Motion of Belt / Pulley Radius.

tog_minusPreparation

GST-T17-O2-Orbiting-Pulley-001

STEP 1: Add a rotating-Part - a Crank

1.Edit the Base-Part

2.Part-Editor: Geometry toolbar > Add Line. Drag from left to right-to add the Line.

3.Part-Editor: Constraints toolbar > Add Horizontal | Click the Line.  (Add dimensions also to fully constrain the Line )

4.Exit the Part-Editor

GST-T17-O2-Orbiting-Pulley-002

5.Mechanism-Editor: Kinematic-element toolbar > Add Part (INSERT key as shortcut)

6.Mechanism-Editor: Drag to add the Part

GST-T17-O2-Orbiting-Pulley-003

7.Mechanism-Editor: Kinematic-elements-toolbar > Add Pin-Joint | Click the start-Point of the new Part and the start-Point of the Line in the Base-Part

8.Mechanism-Editor: Kinematic-FBs toolbar > Add Motion-Dimension FB | Click the Pin-Joint, the horizontal Line, and the CAD-Line in the Part.

9.Click OK-tiny-11-15 in the Command-Manager.

GST-T17-O2-Orbiting-Pulley-004

STEP 2: Add a sketch-loop to define the belt-path.

1.Edit the rotating Part

Add the belt-path as a sketch-loop. Use the Hover + Drag technique (faster) or use Merge-Points in the Part-Editor

2.Part-Editor: Geometry toolbar > Add Line x 2 | Drag to add the Lines approximately parallel to the X-axis of the Part - see sketch to the left

3.Part-Editor: Geometry-Editor > Add Arcs x 2 | Hover + Drag from the end-Point of a Line to the start-Point of a Line, then Drag again to approximate the radius  of the arc.

4.Part-Editor: Constraints toolbar > Add Coincident | Click the center-Point of an Arc then the start-Point of the CAD-Line at the Origin of the Part.

5.Part-Editor: Constraints toolbar > Add Coincident | Click the center-Point of an Arc then the X-axis of the Part.

GST-T17-O2-Orbiting-Pulley-005

1.Part-Editor: Geometry toolbar > Add Dimension | Click each Arc to define the radius of each Arc.

2.Exit the Part-Editor

STEP 3: Add a Motion FB to the sketch-loop

1.Mechanism-Editor: Kinematic-FBs toolbar > Add Motion-Path FB

2.Mechanism-Editor:  Click the sketch-loop - the belt path.

3.Click OK-tiny-11-15 in the Command-Manager

GST-T17-O2-Orbiting-Pulley-006

STEP 4: Add a Linear-Motion FB

1.Mechanism-Editor: Kinematic-FBs toolbar > Add Linear-Motion FB | Click the graphic-area

STEP 5: Add a Part

We must add a Part to the other end of the sketch-loop. We will add a Pulley with this Part - see below.

tog_minusAdd Pulley × 2

GST-Icon-AddPulley

STEP 1: Click Kinematic-element toolbar > Add Pulley

GST-T17-O2-Orbiting-Pulley-007

Add Pulley opens in the Command-Manager.

1.Click the Pin-Joint at the origin of the rotating-Part.

2.Click the Motion-Path FB

The Part-Editor opens. It shows the sketch-loop the will become the Belt

3.Click the Dimension of the Arc sketch-element at the origin of the CAD-Line

The Part-Editor closes

4.Click the Base-Part.
Select the Base-Part because the Pulley is fixed to the Base-Part.

 

GST-T17-O2-Orbiting-Pulley-008

MechDesigner adds the Pulley. It is Cyan color. It is a Driving-Pulley.

 

 

 

You must do Add Pulley two(2) x to add a Pulley to each Arc.

GST-T17-O2-Orbiting-Pulley-009

STEP 2: Click Kinematic-element toolbar > Add Pulley AGAIN

1.Click the Pin-Joint at the origin of the Part at the end of the belt-path.

2.Click the Motion-Path FB - we click the same Motion-Path FB as it is the same belt-path.

The Part-Editor opens. It shows the sketch-loop the will become the Belt

1.Click the Dimension of the Arc sketch-element at the end of the belt-path

The Part-Editor closes:

2.Click the Part at the other end of the belt-path

The Pulley has a Magenta color. This means it is a Driven-Pulley.