Step 15.3: Piggyback-Slider 2

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Step 15.3: Piggyback-Slider 2

Piggyback-Slider Set 2

Why do we need another set of Piggyback Sliders?

We will add a tool to a chain-link. Each chain-link has two Pin-Joints. The Pin-Joints move along the path of the chain. One Pin-Joint moves ahead of the other.

Our plan is to use two sets of Piggyback-Sliders. Each set moves along the same chain-path, but one set moves ahead of the other. A Point on each set locates a Pin-Joint on the chain-link.

In this Step, we add the second set of Piggyback Sliders.

The second set move ahead of the first set by 30º of the Master-Machine-Angle.

They are ahead by 30º because there are 12 tools and 360/12 = 30º.


When we add the second set of Piggyback Sliders, we can:

Use again the horizontal Line in the Base-Part for Slider-X2.

Use again the X-axis and Y-axis motions for Slider-X2 and Slider-Y2


Add Piggyback Sliders - Slider Set 2

Add the new Sliders:

Two Sets of Piggyback Slider

Two Sets of Piggyback Slider

1.Add a sliding-Part to the same Line used by Slider-X

2.Edit the new sliding-Part, add a vertical Line. Close the Part-Editor

3.Add a sliding-Part to the vertical Line

4.Add a Motion-Dimension FB to the sliding-Part that moves along the horizontal Line - rename it to Slider-X2

5.Add a Motion-Dimension FB to the sliding-Part that moves along the vertical Line - rename it to Slider-Y2

6.Edit the Base-Values of each new Motion-Dimension FB to equal the Base-Values of Slider-X and Slider-Y

Add the Function-Blocks

Function-Blocks for Piggyback Sliders

Function-Blocks for Piggyback Sliders

1.Add a Motion FB.  Edit it to open the Motion FB dialog, select the X-axis motion.

2.Add a Motion FB: Edit it. In the Motion FB dialog, select the Y-axis motion.

3.Rename the Motion FBs correspondingly to X2 and Y2

4.Add a Gearing FB. Edit it. In the Gearing FB dialog: edit After Gear Ratio = 30

5.Connect the existing Linear-Motion FB to the Gearing FB

6.Connect the Gearing FB to the two Motion FBs (X2, and Y2)

7.Connect the Motion FB with the name X2 to the Motion-Dimension FB that controls Slider-X2

8.Connect the Motion FB with the name Y2 to the Motion-Dimension FB that controls Slider-Y2


When you cycle the mechanism, Slider-X2/Y2 lead Sliders-X/Y by 30º of the MMA.