In this tutorial, a plate cam with a translating follower will be designed.
A translating roller follower operating with a plate nongroove cam is to rise 1 inch over 90 degrees of cam rotation, dwell for 90 degrees, then fall back to the starting point over 90 degrees. A dwell of 90 degrees will complete the cam.
The timing chart for the motion above will look like this:
1. With the timing chart we can now start Cam Designer SE. Open Cam Designer SE, an the first dialog you will see is the About:
2. Click OK and you will get the Users Dialog, as seen below. Select the user you want and click OK. See Select user Dialog for how to use this.
3. This will then bring up the Cam Designer SE Main Window:
4. Click the Kinematics Button, or, Click Kinematics in the menu, or Atl K to bring up the Kinematics Form.
5. There are some things that need to be selected before we start adding the motions of the follower. At the top of the form there is a section for selecting the Units, Cam Type and Follower Type, plus the Kinematics Starting Angle. Cam Type and Follower Type must be chosen before any motion data is entered; otherwise, if you try to change either of these after motion data is entered, all the data will be lost. In the case of this tutorial, the Cam Type and Follower Type is as shown.
6. In this tutorial we are going to use Cycloidal for the rise of 1 inch in 90 degrees of cam rotation. So click on the Profile dropdown and select Cycloidal, enter 90 in the Segment Amount, 1 in Segment Incr. 1 in Follower Displacement and 0 in Final Velocity. The Kinematics Form will look like this:
7. Click New and the kinematics for that segment will be computed and the Kinematics Form will look like this:
8. Notice the the All Segments Data now shows the first segment and the Graph shows the results of the computation. Another thing to notice is that the edit boxes in the Individual Segment Data are blanked out ready for new data. NOTE: If Save is clicked the segment will be computed, but the edit boxes will not be blanked. Any changes, then, will be to the segment just saved.
9. Enter the remainder of the segments and the Kinematics Form will look like this:
10. To edit any of the segments, click on the row of the segment and all of the data will be entered in the edit boxes ready to change. Click on the third row down and now change the profile to Modified Sine. The Form will look like this:
11. Notice that the Follower Information has changed from to there is now a C Factor. For this term, refer to the Modified Sine Profile. The Initial and Final Fraction are θ/β decimals shown in the Cycloidal Profile; therefore, the entire Cycloid will be from Initial Fraction = 0, to Final Fraction = 1. The first half of a cycloid is from Initial Fraction =0 to Final Fraction =0.5 and the last half is from Initial Fraction =0.5 to Final Fraction =1.
12. Click Save for this change and the Kinematics Form will be like this: Notice: the change in the third segment and the lower acceleration.
13. Now change the output by clicking on the Radio Buttons and see the changes at the bottom of the form. Refer to Kinematics for help on this. Also you may want to look at this video. Kinematics Basics
14. Now to compute the cam based on the Kinematics. In the Main Window, click the Geometry Button, or , select Geometry from the menu, or Alt G and the Geometry Form will appear:
15. Now we need to select the Cam Type and Follower Type. NOTE: The radio buttons in the Cam Type list is dependent on the license you own. For the Basic license, only Plt will be shown.
16. Here is the data we are going to use for this tutorial:
17. Input this data in the Geometry Form and select the Graph radio button in Output and the Geometry Form will look like this:
18. Notice both the Geometry and Kinematics have Unnamed at the top: This is because they have not been saved to disc. Also, look at the Cam Tree in the Main Window and see what is listed there: Neither the Kinematics, Geometry, or the Cam itself has been saved. You can save the Kinematics and Geometry data separately, or save the Cam with both the Kinematics and Geometry saved in one file. If you choose to save the Cam without saving the Kinematics and Geometry separately, the Kin and Geo in the Cam Tree will remain Unnamed. This is an indication that their data is only in the Cam.camx file. At any time later this data can be saved separately. When the data is saved separately, the name given to the file will be listed in the Cam Tree. To show how this is done, go back to the Kinematics Form and click on the Save button and select Save As from the dropdown. Select a folder to save the data in and give it the name Plate Translator Tutorial 1. Do the same to the Geometry and then notice the Cam Tree:
19. Now click on the Cam Drawing and the drawing will look like this:
20. Add a follower, export the DXF or Surface Curve Vectors and create a Solid model of the cam. Also, you an view this video.