About Generic Gear Pairs
A generic gear pair is a gear which can be created on any combination of motion axes:
Two rotation axes
A rotation axes and a translation axis
Two translation axes
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All legacy gears are displayed as generic.
To create other (dynamic) types of gear pairs, you must have a Mechanism Dynamics license.
Create a generic gear pair to define a motion relationship between two motion axes. Each gear in a gear pair requires two rigid bodies with a motion axis connection. The generic gear pair connection constrains the velocity of the two motion axes but not the relative spatial orientation of the rigid bodies that are connected by them. Use the Drag dialog box for the following purposes:
To change the orientation of the rigid bodies in your gear pair to satisfy other physical constraints in the mechanism
To specify servo motor profiles
To configure the beginning orientation of the gear bodies in your gear pair
Because a generic gear pair is considered a velocity constraint and is not based on the model's geometry, you can specify the gear ratio directly and you can change the pitch circle diameter values. The surfaces of the two moving rigid bodies in a gear pair need not be in contact for the gear pair to work. You can change gear ratios without creating new geometry.
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The gear pairs in Mechanism Design are available in Design Animation. Use them to create an animation of the relative velocity of the two gear bodies or to disable the gear-pair connection during a portion of the animation.