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Step 5.5: Cranks, Rockers and Sliders

Contents

Cranks, Rockers, Sliders

In this step, we connect these Function-Blocks (FB):

•	A Linear-Motion FB

•	A Motion-Dimension FB

•	A Motion FB and a Gearing FB

These FBs, together, specify how and when a Crank, Rocker or Slider moves.

A Rocker

A Rocker is a Part that rotates around a Pin-Joint with a motion as defined by motion-values at the input-connector of a Motion-Dimension FB.

QST6-3-4

The image shows a Rocker. To add a Rocker:

1.	Add a Motion-Dimension FB to a Pin-Joint

The Base-Value is 40º

2.	Add a Motion FB to the graphic-area.

3.	Add a Linear-Motion FB to the graphic-area.

4.	Drag wires to connect the Linear-Motion FB to the Motion FB to the Motion-Dimension FB

5.	To edit the FBs, double-click the FB icons.

A Crank

In MechDesigner, the Crank is a simplified Rocker. It rotates at constant speed.

QST6-3-1

The 'Crank':

1.	A Part joined to a 'kinematically-defined' Part with a Pin-Joint

2.	The angle between the parts defined with a Motion-Dimension FB

3.	Add and connect a Linear-Motion FB to the input of the Motion-Dimension FB

To reverse the direction of the Crank, add and connect a Gearing FB between the Linear-Motion and Motion-Dimension FB, and edit it to change the Gearing Ratio parameter to -1.

A Slider

A Slider is a Part that reciprocates, back-and-forth, along a Slide-Joint.

QST6-3-5

The image shows a Slider. To add a Slider:

1.	Add a Motion-Dimension FB to a Slide-Joint

The initial position, here 7.98mm, is the 'Base-Value'

2.	Add a Motion FB to the graphic-area

3.	Add a Linear-Motion FB to the graphic-area.

4.	Connect the Linear-Motion FB to the Motion FB to the Motion-Dimension FB.

5.	To edit the FBs, double-click the icons.

See the video to the left.

Tutorial and Reference Help Files for MechDesigner and MotionDesigner 13.2 + © Machine, Mechanism, Motion and Cam Design Software by PSMotion Ltd