Cam Properties

The cam object is a point object located in the Cam (Imperial).sta and Cam (Metric).sta templates. Cam properties can be edited in the Object Info palette.

 

Parameter	Description
Prime Circle Radius	Specify the prime circle radius
Cam Type	Select plate or groove
Outside Dia.	Enabled if Groove is selected in Cam Type. Enter the outside diameter for groove cam types.
Cam Drawing Incr. (Deg.)	Enter the cam drawing increment, in degrees; this parameter affects how the cam is drawn. The larger the value, the less smoothly the cam is drawn.
Cam Speed (rpm)	Specify the cam rotation in revolutions per minute (rpm); this value is used to calculate the velocity and acceleration of the cam follower
Follower Type	Select one of the follower types
Follower Dia.	Enter the follower diameter
Follower Offset	Enabled if Offset Translating Roller or Offset Pivot Roller is selected in Follower Type. Indicate the distance between the center of the cam and the follower center for the offset follower types.
Pivot X/Y (from cam center)	Enabled if Pivot Roller is selected in Follower Type. Specify the x and y distance from the cam center to the pivot arm for pivot roller follower types.
Draw Followers	Select to display the followers
Follower Incr. (Deg.)	Determine at what angles to display followers by entering the follower increment in degrees (to show only the actual follower, enter 360). If a segment of the cam ends on an angle that does not correspond to the follower increment, the additional follower is also displayed.
Draw Prime and Offset Circles	Select to display both the prime and offset circles
Draw Follower Path	Select to display the follower path
Draw Radii	Select to draw a radius from each follower to the center mark
Draw Center Mark	Select to draw a center mark
Write Data to File	Select to write the current cam data and results to a text file; by default, the file name is Cam Data.txt, and it is located in the application folder
Data Incr. (Deg.)	Specify the increment at which the displacement, velocity, and acceleration of the cam follower are calculated
Define Cam Profile	Click to specify the profile of each cam segment; for more information, see Defining the Cam Profile
Animate	Click to animate the cam; for more information, see Animating Cam Movement
Reset Cam to 0	Click to position the cam back to zero degrees; for more information, see Resetting the Cam to Zero Degrees

Defining the Cam Profile

Specify the profile of each cam segment in the Define Cam Profile dialog box.

To define the cam profile:

1.	Select the cam, and click Define Cam Profile on the Shape tab of the Object Info palette.

The Enter Value dialog box opens.

2.	Enter the number of cam segments and click OK.

The Define Cam Profile dialog box opens for specifying the parameters for each segment. Click OK to update cam diagram.

Parameter	Description
Type of Motion	Select the type of motion for each segment
End Angle	Specify the end angle for the segment
Displacement	Specify the displacement at the end point of the segment

Animating Cam Movement

The effect of parameter changes to the cam design can be evaluated by animating the cam.

To animate the cam:

1.	Select the cam, and in the Object Info palette, click Animate.

The Rotate Cam dialog box opens.

2.	Adjust the relative speed by moving the slider along the Speed bar.

3.	Click Rotate.

The cam rotates at the relative speed specified and the follower moves accordingly.

Since the animation is for illustrative purposes only, the Cam Speed parameter does not affect the animation. However, the animation is affected by the selected speed in the Rotate Cam dialog box; the larger the increment, the faster the cam appears to rotate. In addition, the computer processor speed also affects the apparent animation speed.

4.	To stop the cam rotation, press any key or click anywhere on the screen.

Resetting the Cam to Zero Degrees

Once the cam rotation stops, the position of the cam remains where it was when it was stopped. To reset the cam to zero degrees (original position), click Reset Cam to 0 on the Shape tab of the Object Info palette.