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# CV Inverse Crank

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# CV Inverse Crank

### Constant-Velocity Inverse Crank

Motion-Description

 This segment is best explained by considering a Point at the end of a Crank when its motion is projected onto a Line. When a Crank rotates with Constant angular velocity, the projected-motion of the Point along the Line is Simple-Harmonic-Motion. When you use CV-Inverse-Crank, the projected-motion of the Point along the Line is Constant Linear Velocity.

#### Motion-Values

 Position at the Start - defined by the three Segment-Parameters - see below. Position at the End - defined by the three Segment-Parameters - see below.

You CANNOT specify the:

 Velocity at the Start or End Acceleration at the Start or End Jerk at the Start or End The actual velocity, acceleration, jerk values, and the distance the Point moves along the Line is a function of the: •Segment-Width •Length of the Rocker/Crank •Segment-Parameters

Segment Parameters

 Typical Segment-Parameters Svhematic to help you understand how to use the CV-Crank motion-law. You can set the: Min Vel (Minimum Velocity) the Angle we add to the Base-Value angle defined by the Motion-Dimension FB Rel Start (Relative Start) Direction angle relative to the angle defined by Min Vel at which Point starts to move along the Orange Line with Constant-Velocity. Rel End (Relative End) Directional angle relative to the angle defined by Min Vel at which Point ends moving along the Orange Line with Constant-Velocity. Note: The Crank rotates Counter-Clockwise when Rel. Start is a Negative and Rel. End is a Positive. The Crank rotates Clockwise when Rel. Start is a Positive and Rel. End is a Negative.

Segment-Range

 Start-Range End- Range 0 ≤ Start-Range < End-Range ≤ 1

CV Inverse-Crank2 x

EXAMPLE Motion with two CV Inverse Crank segments.

Segment 1: Constant-Velocity Inverse-Crank

X-axis : 0 to 90º

Segment Parameters are:

Angle of Minimum Velocity = 90º

Relative Start Angle = -30º

Relative End = 30º

With these Parameters:

When X-axis = 0º ; Y–axis = 60º.

When X-axis =90 ; Y–axis = 120º

Segment 2: Flexible-Polynomial

X-axis : 90 to 180º

Y-axis at Start P=120. V, A, J flow from the end of the Constant-Crank-Velocity Segment.

Y-axis at End 240º

Segment 3: Constant-Velocity Inverse-Crank

X-axis : 180 to 270º

Segment Parameters are:

Angle of Minimum Velocity = 270º

Relative Start Angle = -30º

Relative End = 30º

With these Parameters:

When X-axis = 180º ; Y–axis = 240º

When X-axis =270 ; Y–axis = 300º

Segment 4: Flexible-Polynomial

X-axis : 90 to 180º

Y-axis P at Start = 300º. V, A, J flow from the end of the Constant-Crank-Velocity Segment.

Y=axis at End = 420º.