Tài liệu CAM CREATED USING GRAPH FEATURE doc

1 ME-430 INTRODUCTION TO COMPUTER AIDED DESIGN CAM CREATED USING GRAPH FEATURE Pro/ENGINEER Wildfire 2.0 Dr. Herli Surjanhata Use Notepad or Text Editor in Unix system to create the following file called cam_disp.pts. The point coordinates represent the cam angle – follower displacement plot. 2 The extension of the file must be .pts In Windows system, be sure to include the quotation in the filename when you save the test file – see Figure. Click - the Create new object icon to create a new part called CAM. Turn-off Use default template box. Click OK button. 3 Select mmns_part_solid as the Units. Note that the Units for the cam will be millimeters. Click OK button. Create a thin cylinder with a hole vertical up by extruding two concentric circular sections. For this protrusion use TOP as sketching plane RIGHT as right reference for orientation of sketching plane See Figure below for dimensioning. 4 Create a DATUM GRAPH to define a dimension on a cam to produce a desired variable offset of the follower as the cam rotates. From Insert pull-down menu, select Model Datum -> Graph 5 Enter a name for the feature: camgraph Create a coordinate system to identify the origin of the graph. Click the Create reference coordinate system icon. Pick the lower left corner of the screen. Create horizontal and vertical centerlines through the origin of the coordinate system. Use - spline icon to sketch and dimension the following curve: 6 Modify the overall dimension to 360 as shown above. Note that pick the spline curve as shown above. Click the spline curve, then select the Modify icon. . Pick File tab. Make sure the Cartesian is selected. Select the coordinate system created in the previous step. Click the Open file icon. First point Second point Third point 7 Open cam_disp.pts. Answer Yes when asked Do you want to continue? Create a horizontal centerline below the coordinate system, and create a new coordinate system at the intersection between the newly created horizontal centerline and vertical center line. Delete the old coordinate system, and dimension the vertical distance between the two centerlines 5 mm: Click this icon to continue. Create the sweep using the graph to control section dimensions as follows: 8 Insert -> Variable Section Sweep Pick the bottom edge of the cylinder. Note: Pick the front bottom half of the circle first, then while holding the Shift key pick the second half of the circle located on the bottom back. Pick the Sweep as solid tool. Pick the Sketch tool. 9 Create a rectangle aligned on one edge to the cross hairs, and change only the height to 8 mm. See dimensioning scheme in Figure. From Tool pull down menu, select Relations. The width of the rectangle (sd4 in the Figure) is controlled by the graph feature using the relation and call to the built-in function evalgraph. Add the following relation for the width sd4 of rectangle. In the message window box, type in: /* use evalgraph to determine dimension sd4 = evalgraph (“camgraph”,trajpar*360) 10 Click OK to accept the relation. Pick the to continue. Click the icon to finish. Note that: Camgraph & trajpar*360 are arguments. Camgraph is datum graph name, and the trajectory parameter trajpar goes from 0 to 1. Create a cut for keyway with the dimensions of 7 mm width and 4 mm height. [...]...Create a protrusion of your name on the top surface of the cam Pick the icon Make sure that Place Along Curve is checked Also replace NJIT with your name 11 Finally, add the necessary rounds and chamfers 12 . 1 ME-430 INTRODUCTION TO COMPUTER AIDED DESIGN CAM CREATED USING GRAPH FEATURE Pro/ENGINEER Wildfire 2.0 Dr. Herli Surjanhata Use. Model Datum -> Graph 5 Enter a name for the feature: camgraph Create a coordinate system to identify the origin of the graph. Click