Add Pulley

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Add Pulley

Add Pulley

See also : Pulley dialog

Pulley / Belt Terminology

Term :

Definition

Pulley :

When you do Add Pulley, we add for you the outline of a Pulley, with teeth, to a rotating-Part - see also Types of Pulley

The rotating-Part of a Pulley must rotate about the center-Point of an Arc that is on the sketch-path of a Belt.

Belt :

A sketch-path to represent the path of the Belt. The motion of a Motion-Point along the sketch-path represents the motion of the Belt.

We relate the angular motion of each Pulley to the linear motion of the Motion-Point on a Belt by the radius of each Pulley.

To control the radius of each Pulley, you can control its number-of-teeth and the Tooth-Pitch of the Belt.

Types of Pulley

You can do Add Pulley to a rotating-Part that is kinematically-defined (Type 1) or is not kinematically-defined (Type 2).

Type 1: A Driving-Pulley :

Before you do Add Pulley, the rotating-Part is kinematically-defined.

After you do Add Pulley, we control the linear motion of a Belt from the angular motion of the rotating-Part (Driving-Pulley).

Add a maximum of one Driving-Pulley to a Belt.

Type 2: A Driven-Pulley :

Before you do Add Pulley, the rotating-Part is not kinematically-defined.

After you do Add Pulley, we control the angular motion of a rotating-Part (Driven-Pulley) from the linear motion of the Belt.

Kinematics-Tree of Pulley

MD-ADD-PULLEY-KINEMATIC-TREE

Driven-Pulley

It is a Pulley-Rocker in the Kinematics-Tree after you do Add Pulley.

A Path-Joint is a child to the Pulley-Rocker.

Driving-Pulley

It is a Part that is kinematically-defined in the Kinematics-Tree before you do Add Pulley.

For example, a Driving-Pulley in the Kinematics-Tree is a Rocker.

Prepare to Add Pulley (TYPICAL)

STEP 1: Add the sketch-path for the Belt.

Sketch-loop as the path of the Belt.

Sketch-loop as the path of the Belt.

STEP 1: Add a sketch-path to represent the path of the Belt.

The sketch-path should include only Lines and Arcs. Usually, add Tangent constraints between each Line and Arc. Do not add equal constraints to the Arcs. The sketch-path is usually a closed sketch-loop. It is usually helpful to fully define the geometry of the sketch-path.

1.Mechanism-Editor: Edit the Base-Part (usually) or Part

2.Part-Editor: Add a sketch-path with Lines and Arcs to represent the path of the Belt. You need one Arc for each Pulley.

3.Part-Editor: Add Tangent constraints between each Line and Arc

4.Part-Editor: Add a dimension to the radius of each Arc. (Do not add Equal constraints between Arcs)

If the rotating-Part is a Rocker for a Driving-Pulley - see STEP 3A:

5.Part-Editor: Add a Line from the center-Point of the Arc that is the rotating-axis of the Rocker / Pulley

Why? You need the Line to add a Motion-Dimension FB to the rotating-Part.
A Line for a Motion-Dimension FB

A Line for a Motion-Dimension FB

STEP 2: Add the Motion-Path FB to the sketch-path

MD-ADD-PULLEY-MOTIONPATH-FB-3

STEP 2: Add a MOTION-PATH FB

Add ONE Motion-Path FB to the sketch-path.

1.Click Function-Blocks menu > Add Motion-Path FB.

2.Click a sketch-element in the sketch-path

The Motion-Path FB is in the graphics-area.

And, a Motion-Point is at the start-Point of the sketch-element you click.

STEP 3: Add a Rotating-Part for a Pulley

A Pulley is a Driving-Pulley or Driven-Pulley. It is a rotating-part.

rotating-Part for a Driving-Pulley

rotating-Part for a Driving-Pulley

STEP 3A: Type 1 - Driving-Pulley

A Driving-Pulley is a rotating-Part that is kinematically-defined before you do Add Pulley.

Add a maximum of ONE Driving-Pulley to a Belt.

1.Add a Rocker with its Pin-Joint at the center-Point of the Arc with a Line (see Preparation 1: 5, above)

OR

1.Add Parts to the model, in which there is a rotating-Part with its Pin-Joint at the center-Point of the Arc in the sketch-path of the Belt - and it is kinematically-defined.
rotating-Part for a Driven-Pulley

rotating-Part for a Driven-Pulley

STEP 3b: Type 1 - Driven-Pulley

A Driven-Pulley is a rotating-Part that is not kinematically-defined before you do Add Pulley.

The motion of the Belt and the Pulley's Pitch-Circle Diameter of the control the motion of a Driven-Pulley.

1.Add a rotating-Part with its Pin-Joint at the center-Point of each Arc with a Driven-Pulley.

Add Pulley

MD-CM-AddPulley-1

STEP 1: Click Add Pulley

Add Rack-Pinion Ball-Screw icon

1.Mechanism menu > Add Pulley

- or -

1.Machine-elements toolbar > Add Pulley

There are four elements to select in the Command-Manager

STEP 2: Click the four elements

1.Click a Pin-Joint at the center of a rotating-Part*.

2.Click the Motion-Path FB.

The Part-Editor opens

3.Click the dimension that controls the radius of the Arc.

The Part-Editor closes

4.Click the rotating-Part* that has a Pin-Joint (see 1) at the center-Point of the Arc (see 3)

* If the rotating-Part is :

•is kinematically-defined - the motion of the Pulley moves the Belt (Driving-Pulley).

•is not kinematically-defined - the motion of the Belt moves the Pulley (Driven-Pulley).

STEP 3: Complete the Command

5.Command-Manager: Click OK-tiny-11-15 in the Command-Manager.

Result:

The schematic of the Pulley shows in the graphics-area.

•Use the Motion-Path dialog to edit the Tooth-Pitch and length of the Belt.

The Pulley has an integer number-of-teeth.

•Use the Pulley dialog to edit the number-of-teeth on each Pulley.
1 x Driving-Pulley (Purple) 1 x Driven-Pulley (Magenta)

1 x Driving-Pulley (Purple)
1 x Driven-Pulley (Magenta)

Do Add Pulley to add 1 x Pulley.

The image shows two Pulleys after you do Add Pulley two times.

Video: Add Pulley:

 

Video: Add Pulley (and the Belt-Path)