Spur Gear
Use the Spur Gear node to model a spur gear. The gear is assumed to be rigid. Select one or more domains to make them a part of the gear.
A spur gear can be connected to another Spur Gear, or a Helical Gear through the Gear Pair node. Two gears can be connected to each other only if they satisfy the Gear Pair Compatibility Criteria.
The gear has the following subnodes to constraint the displacement and rotation, to apply forces and moments, and to add mass and moment of inertia:
These subnodes are described in the Structural Mechanics Module User’s Guide:
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Fixed Constraint (Rigid Domain)
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Prescribed Displacement/Rotation
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Applied Force (Rigid Domain)
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Applied Moment (Rigid Domain)
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Mass and Moment of Inertia (Rigid Domain)
Sketch
This section shows a sketch of a spur gear. Some of the inputs are also highlighted in the sketch.
Gear Properties
Specify the properties of a spur gear in this section.
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Select the Gear mesh — External or Internal.
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Enter Number of teeth n.
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Enter Pitch diameter dp.
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Enter Pressure angle α.
Gear Axis
The gear axis is defined as the axis of rotation of the gear. The gear axis is defined as the axis of rotation of the gear. To define the axis, choose Specify direction or Select a parallel edge.
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For Specify direction, enter a value or expression for eg. The default is (0, 0, 1). The direction is specified in the selected coordinate system.
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For Select a parallel edge, an edge can be selected on the Gear Axis subnode, which is added automatically. The vector from the first to last end of the edge is used to define the gear axis. Any edge in the model can be used. Select the Reverse direction check box to reverse the direction of the gear axis.
Density
The default Density ρ is taken From material. In this case, the material assignment for the domain supplies the mass density. For User defined enter another value or expression.
The density is needed for dynamic analysis. It is also used when computing mass forces for gravitational or rotating frame loads, and when computing mass properties (Computing Mass Properties).
Center of Rotation
The center of rotation is the point about which the rotation of the gear is interpreted. Select an option from the list — Center of mass, Centroid of selected entities, or User defined.
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For User defined, enter the coordinates of center of rotation Xc in the global coordinate system.
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For Centroid of selected entities, select an Entity level — Boundary, Edge (3D components), or Point.
Once chosen, a default Center of Rotation: Boundary, Center of Rotation: Edge, or Center of Rotation: Point subnode is added.
Spur Gear Theory
Location in User Interface
Context Menus
 Solid Rotor>Gears>Spur Gear
Solid Rotor, Fixed Frame>Gears>Spur Gear
Ribbon
Physics tab with Solid Rotor or Solid Rotor, Fixed Frame selected:
Domains>Gears>Spur Gear