Pulleys Driven By Belt

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Pulleys Driven By Belt

Fixed Pulleys centers: Pulleys driven by a Belt

This design arrangement is a little more unusual than the Belt driven by a Pulley.

Physically, the Belt is wrapped around freely rotating Pulleys. The Belt is driven by motion-values at the input-connector to the Motion-Path FB.

tog_minusPreparation

GST-17-1-Option1-BbyP-0

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

a)Base-Part : Add a sketch-loop to represent the path of the Belt

In this example, the sketch-loop has two Arcs and two Lines.

b)Part-Editor:Add a LineRed-14-1b and merge its start-Point with center-point of the Arc.

c)Part-Editor: You MUST dimension each Arc Red-14-2.

d)Part-Editor (Optionally, but a good idea:): Dimension the distance between the Arcs and the length of the lineRed-14-1b you have added in STEP 2.

The radius of each Arc is not important.

Command-Manager:  Add Motion-Path FB

Command-Manager:
Add Motion-Path FB

e)Exit the Part-Editor

STEP 2: Add a Motion-Path FB

a)Mechanism-Editor: Kinematic FB toolbar > Add Motion-Path FB

b)Mechanism-Editor: Click the sketch-loop that represents the path of the belt.

c)Click OK-tiny-15-18 in the Command-Manager

GST-17-1-Option1-PbyB-B

A Motion-Point shows at the start-Point of the sketch-element you select in the sketch-loop. It is a small triangle inside the Point symbol.

STEP 3.Add a Linear-Motion FB

a)Mechanism-Editor: Kinematic FB toolbar > Add Linear-Motion FB

b)Mechanism-Editor: Click the graphic-area

Connect the Linear-Motion FBRed-14-4 to the Motion-Path FBRed-14-3 with a wire.

Motion-values at the output of the Linear-Motion FB are 0-360 .

Because the Data-Type are Rotary, 0-360 moves the Motion-Point the total length of the sketch-loop.

GST-17-1-Option1-PbyB-C

 

STEP 4.Add PartsRed-14-5 : one part for each Pulley / Arc

The length of each Part is not important for the Pulley or belt.

STEP 5.Add a Pin-JointRed-14-6 between the start-Point of each Part and the center-Point of each Arc

The Pin-Joint will be at the center of the Pulley.
tog_minusAdd Pulley command

GST-Icon-AddPulley

STEP 1: Add the Pulleys  

a)Mechanism-Editor: Machine elements toolbar > Add Pulley

Add Pulley opens in the Command-Manager.

Click, in the graphic-area, the four(4) elements from top to bottom - see images Red-14-6Red-14-3Red-14-2Red-14-5 above

Red-14-6 The Pin-Joint

Red-14-3 The Motion-Path FB

The Part-Editor opens to show the sketch-loop to which you added the Motion-Path FB.

Red-14-2 The Radius Dimension of the Arc sketch-element with the Green rotating-Part

The Part-Editor closes.

Red-14-5 The Part joined with a Pin-Joint at the center of the Arc.

b)Click OK-tiny-11-15 to complete the command and to close the Command-Manager.

Do a) and b) again for the two Pulleys.
Command-Manager

Command-Manager
Two Pulleys Driven by the Belt'

Two Pulleys Driven by the Belt'

Notes:

Driven-Pulleys.

The angular-velocity of each Pulley is defined by the linear-speed of the Motion-Point along the sketch-loop (Belt) and the radius of each Pulley.

•When you add a Pulley, the radius of the Arc in the sketch-loop will change to give an integer number-of-teeth on the Pulley.

•Driven-Pulleys are Purple

•Edit the number-of-teeth with the Pulley dialog.

•Edit the Tooth-Pitch in the Motion-Path FB.
tog_minusKinematics Tree Pulley-Rocker
Kinematics-Tree - Pulley  Path-Joint

Kinematics-Tree - Pulley
Path-Joint

The two Driven Rockers are in the Kinematics-Tree as a Pulley-Rockers