Part and Assembly Modeling with ANSYS DesignModeler 14 Huei-Huang Lee
Contents
Contents Preface 2 Section A. Sketching
5
Exercise 1. Arm 6
Exercise 1a.
Structural Analysis of the Arm
Exercise 2.
Ratchet Stop
Exercise 3.
Ratchet Wheel
Exercise 4.
Cover Plate
Section B. Part Modeling
21
28 35
44
54
Exercise 5. Crank 55
Exercise 6.
Geneva Gear Index
Exercise 7.
Yoke
Exercise 8.
Support
Exercise 8a.
Structural Analysis of the Support
Exercise 9.
Wheel
Exercise 10.
Pipe
Exercise 11.
C-Bar Dynamometer
Exercise 11a.
Deformation of the C-Bar
Exercise 12.
Threaded Shaft
Exercise 13.
Lifting Fork
Exercise 14.
Caster Frame
64
72 79 88
94 98 106 111
119
124 130
Section C. Assembly Modeling
144
Exercise 15. Threaded Shaft Assembly 145
Exercise 16.
Universal Joint
152
Exercise 16a.
Dynamic Simulation of the Universal Joint
Exercise 17.
Clamping Mechanism
Exercise 17a.
Simulation of the Clamping Mechanism
Section D. Concept Modeling
165
176 197
215
Exercise 18. 2D Solid Modeling (Arm) 216
Exercise 18a.
Structural Analysis of the Arm Using 2D Model
219
Exercise 19.
Surface Modeling (Support)
Exercise 19a.
Structural Analysis of the Support Using Surface Model
Exercise 20.
Line Modeling (Space Truss)
Exercise 20a.
Structural Analysis of the Space Truss
225 234 240
230
1
2
Preface
Preface Use of the Book This book is designed for those who want to learn how to create parts and assembly models using ANSYS DesignModeler. The author assumes no previous CAD/CAE experiences to begin with the book.
This book is mainly designed as an auxiliary tutorial in a course using ANSYS as a CAE platform. In particular,
this book can serve as a preparation to the author's another book Finite Element Simulations with ANSYS Workbench 14, which emphasizes on finite element simulations rather than geometry modeling such that the exercises on geometry modeling (especially assembly modeling) may not be adequate.
ANSYS DesignModeler ANSYS DesignModeler is a CAD program running under ANSYS Workbench environment. The DesignModeler can create geometries as sophisticated as any other CAD programs. Yet, many engineers choose to create geometry models using other CAD programs (e.g., Pro/Engineer, SolidWorks) and then import them into an ANSYS simulation module (such as Mechanical) for simulations. One of the reasons may be that, other than the training materials provided by the ANSYS Inc., there exist no tutorials in the bookstore. That is the main reason that I created this book.
The DesignModeler is designed specifically for creating models which can be seamlessly imported into an ANSYS
simulation modules (such as Mechanical). Therefore, if a geometry model is solely used for ANSYS simulations, I strongly suggest that we create the model from scratch using DesignModeler, rather than other CAD programs, to avoid any unnecessary incompatibilities.
Structure of the Book There are 20 exercises and 8 appendices in the book; each of them is designed in a step-by-step tutorial style. The 20 exercises involve creating parts and assemblies models, while the 8 appendices show how to perform simulations using some of the models. If you are not currently interested in simulations, you may freely skip the 8 appendices without affecting the learning of the 20 exercises.
An assembly consists of two or more parts. Each part can be viewed as boolean operations (union, subtraction,
etc.) of simpler 3D bodies. Each of the 3D bodies usually can be created by a two-step operation: drawing a 2D sketch on a 2D plane and then generate the 3D body by extrusion, revolution, sweeping, or skin/lofting.
The book is divided into 4 sections. Section A lets students familiarize with sketching techniques. Section B
contains exercises of part modeling. Section C consists of exercises of assembly modeling. The last section introduces the creations of concept models, including 2D models, surface models, and line models. A concept model is a simplification of a 3D models, and is usually easier to create and more efficient to be simulated.
Preface
3
Companion Webpage A webpage dedicated to this book is maintained by the author: http://myweb.ncku.edu.tw/~hhlee/Myweb_at_NCKU/ADM14.html The webpage contains links to finished project files of each exercise and appendix. If everything works smoothly, you do not need them at all. Every model can be built from scratch according to the steps described in the book. The author provides these project files just in some cases you need them. For examples, if you have troubles to follow the geometry details in the textbook, you may need to look up the geometry details from the project files.
Huei-Huang Lee Associate Professor Department of Engineering Science National Cheng Kung University Tainan, Taiwan
[email protected] myweb.ncku.edu.tw/~hhlee
4
Section A. Sketching
Section A Sketching
An assembly is a combination of parts. From manufacture point of view, a part is a basic unit for manufacturing process. Many parts can be created by a two-step operation: drawing a 2D sketch on a plane and then generate a 3D body by extrusion, revolution, sweeping, or skin/lofting. The exercises in Section A are designed to introduce the 2D sketching techniques provided by the DesignModeler. Each part created in Section A involves drawing a sketch and then extrude to generate a 3D solid body representing the part. Although it can be used as a general purpose CAD software, the DesignModeler is particularly designed for creating geometric models to be analyzed (simulated) under the ANSYS environment. To let the readers understand what it means by analysis (simulation) as early as possible, an exercise (Exercise 1a) is appended right after Exercise 1 to perform a structural analysis for the part created in Exercise 1. However, the reader has option to skip Exercise 1a without affect the subsequent learning of geometric modeling.
5
6
Exercise 1. Arm
Exercise 1 Arm
1-1 Introduction In this exercise, we will create a 3D solid model for an arm, which is a part of a clamping mechanism [1]. The clamping mechanism will be introduced in Exercise 17 and simulated in Exercise 17a. The arm model consists of a single solid body, which can be generated by extruding a sketch by a thickness of 0.125 inches [2]. Before creating a geometry model, we must set up a global coordinate system. For this exercise, we arbitrarily choose the global coordinate system as shown [3]. Note that the origin is on the back surface of the part.
[1] The arm is a part of a clamping mechanism.
Y
R0.313
1.375
R0.313
X 3 × D0.25
[3] The global coordinate system.
2.25
R0.25
[2] Details of the arm.
Unit: in. Thickness: 0.125 in.
R0.5
Exercise 1. Arm
1-2 Start Up DesignModeler
[1] Launch ANSYS Workbench.
[2] The (graphical user interface) shows up.
[3] Click the plus sign (+) to expand . The plus sign becomes minus sign.
[7] Double-click to start up the DesignModeler.
[5] A system is created in the area.
[4] Double-click to create a system.
[6] You may click here to show the messages from ANSYS Inc. To hide the message, click it again.
7
8
Exercise 1. Arm
[8] shows up.
[9] Select as length unit.
[10] Click . Note that, after clicking and entering DesignModeler, the length unit cannot be changed anymore.
Speech Bubbles 1. In this book, each exercise is divided into subsections (e.g., 1-1, 1-2). In each subsection, speech bubbles are ordered with numbers, which are enclosed by pairs of square brackets (e.g., [1], [2]). When you read, please follow the order of speech bubble; the order is significant. 2. The square-bracket numbers also serve as reference numbers when referred in other text. When in the same subsection, we simply refer to a speech bubble by its number (e.g., [1], [2]). When in the other subsections, we refer to a speech bubble by its subsection identifier and its bubble number (e.g., 1-2[1]). 3. When a circle is used with a speech bubble, it is to indicate that mouse or keyboard ACTIONS are needed in that step [1, 3, 4, 7, 9, 10]. A circle may be filled with white color [1, 4, 7] or unfilled [3, 9, 10]. A speech bubble without a circle [2, 8] or with a rectangle [6] is used for commentary only, i.e., no mouse or keyboard actions are needed.
Workbench Keywords A pair of angle brackets is used to highlight an Workbench keyword (e.g., in [3]). Sometimes, if the angle brackets do not add any clarity, they may be dropped (e.g., DesignModeler).
Clicking and Selecting When we say "click" or "select," we mean left-click the mouse button.
Exercise 1. Arm
1-3 Prepare to Draw a Sketch on
[1] By default, is the current sketching plane (active plane).
[3] Click to rotate the view angle so that you look at the current sketching plane.
[2] Click to switch to . Note that there are 5 toolboxes available: Draw, Modify, Dimension, Constraints, and Settings. is the default toolbox. [4] By default, the ruler is on. In the next step, we will turn off the ruler to make more sketching space.
[6] This is the global coordinate system.
[5] Select to turn it off. For the rest of this book, we always leave the ruler off.
[7] This is the plane (local) coordinate system.
9
10
Exercise 1. Arm
1-4 Draw a Circle with Dimension [6] As soon as you begin to draw, a name is assigned to the sketch and it becomes the active sketch.
[1] Select tool.
[7] Select toolbox.
[2] In case you don't see the tool, scroll down to reveal the tool.
[5] Move the mouse away from the center and then click the mouse to create a circle with arbitrary radius.
[4] Move the mouse around the origin until a (Point) appears and then click the mouse to locate the center of the circle. The ability to "snap" a point is a feature of the DesignModeler, called .
[3] It gives you hints for using the tool.
[11] It is possible that the circle becomes too small. Select tool to fit the sketch into the graphics window. Now, we may need to adjust (move) the position of the dimension.
[8] Select tool.
[10] In the , type 0.25 for the diameter.
[9] Select the circle, move the mouse outward, and then click to create a dimension. Note that the circle turns blue, meaning the circle has fully constrained (fixed in the space).
Exercise 1. Arm
11
[14] Whenever necessary, select tool to fit the sketch into the graphics window. [12] Select tool. Remember to scroll down to reveal a tool if you don't see the tool.
[13] Select the dimension, move to a suitable position, and then click again.
[15] Select tool. You may need to scroll down to reveal the tool if you don't see the tool.
[16] Click to turn the dimension name off. Note that automatically turns on.
[17] Instead of displaying dimension name, now the dimension value is displayed. For the rest of the book, we always display dimension values instead of name.
12
Exercise 1. Arm
1-5 Draw Two More Circles
[2] Select toolbox.
[4] Move the mouse around the horizontal axis until a (Coincident) appears and then click the mouse to locate the center of the circle. This center is snapped on the horizontal axis.
[1] Click anywhere in the graphics window and then scroll the mouse wheel down to zoom out the sketch roughly like this.
[5] Move the mouse until an (Radius) appears and then click the mouse. The radius dimension is constrained to be the same as the first circle. Note that the circle is greenish-blue, meaning it is not fully fixed in the space yet. A horizontal location is needed to fully defined the circle.
[3] Select tool.
[6] Create another circle in a similar way. Make sure a and an appear before clicking. A vertical location is needed to fully defined the circle.
Exercise 1. Arm
[8] Select the vertical axis. Note that the shape of the mouse cursor changes when your mouse is on the axis.
13
[12] Remember that you always can use and scroll the mouse wheel [1] to zoom in/out the view. Also, to "pan" the view, simply move the mouse while holding the control-middle-button. [10] Move the mouse upward roughly here and click to locate a horizontal dimension. Note that the circle turns blue (fully constrained).
[7] Select toolbox and then select tool. [11] In the , type 1.375 for the horizontal dimension.
[9] Select the center of the circle. Note that the shape of the mouse cursor changes when your mouse is on the point.
[13] Select tool.
[16] Before going further, make sure you familiarize the two most frequently used view operations: scrolling the mouse wheel to zoom in/out the view and moving mouse with control-middle-button to pan the view.
[15] In the , type 2.25 for the vertical dimension.
[14] Select horizontal axis, select the center of the lower circle, move the mouse leftward roughly here, and click to locate a vertical dimension. The circle turns blue.
14
Exercise 1. Arm
1-6 Draw Three Concentric Circles
[2] Select the tool, and create a radius dimension for the circle. In the , type 0.313 for the radius.
[1] Select the tool, and draw a concentric circle. Make sure a appears before defining the center.
[4] With the tool still selected, draw a concentric circle. Make sure a appears before defining the center.
[3] Select the tool, and draw a concentric circle with the same radius as the previous circle. Make sure a appears before defining the center and an appears before defining the radius.
[5] Select the tool, and create a radius dimension for the circle. In the , type 0.5 for the radius.
Exercise 1. Arm
1-7 Draw Tangent Lines
[1] Select the tool, and then select the two circles to be tangent to. A tangent line is created.
[2] Create additional three tangent lines in a similar way.
15
16
Exercise 1. Arm
1-8 Draw a Fillet [1] Select the tool, and type 0.25 for .
[2] Select these two lines. A fillet is created. Note that the fillet is not bluecolored. We need to specify the radius. The radius typed in [1] is not necessarily the final dimension; it just serves as a default dimension.
[3] Select the tool, and create a radius dimension for the fillet. You don't need to type in the , since the default value [1] is automatically used. Note that the color turns blue now.
Exercise 1. Arm
17
1-9 Trim Away Unwanted Segments [1] Select the tool, and turn on , meaning that the axes will not serve as trimming tools.
[3] Click to trim away two other arcs.
[2] Click the circle roughly here to trim away the arc. Note that when you select an edge (a line or a curve), the remaining edges will serve as trimming tools.
[4] The sketch after trimming.
18
Exercise 1. Arm
1-10 Extrude the Sketch to Create the Arm [1] Select tool.
[6] Click to produce a 3D solid body.
[3] Click the little cyan sphere to rotate the view into an isometric view.
[2] It automatically switches to , in which a is displayed, which will be explained later.
[4] Type 0.125 for the .
[7] Click to turn off the display of XYPlane (and the sketches it contains).
[5] The active sketch is automatically taken as .
1-11 Save the Project and Exit Workbench
[2] In the , save the project as "Arm."
[1] Select . The disappears.
[3] Select to quit from the Workbench.
Exercise 1. Arm
19
1-12 Review Global Coordinate System Before creating a geometry model, you must set up a global coordinate system (1-1[3], 1-3[6]).
Workbench GUI In the (1-2[2]), you can create a system (1-2[4]) and start up DesignModeler (1-2[7]). Other capabilities will be introduced later.
Project Schematic Created systems appear on the , an area in the .
DesignModeler GUI Geometries are created entirely within the (1-2[8]).
Length Unit Before creating a model in the DesignModeler, you must choose a length unit (1-2[9, 10]). The length unit cannot be changed thereafter.
Mouse Operations Click -- Left-click the mouse button. Select -- Left-click the mouse button. Double-Click -- Left-click the mouse button twice. Zoom In/Out -- Scroll the mouse wheel Pan -- Move the mouse while holding control-left-button. Other mouse operations will be introduced later.
Current Sketching Plane Each sketch is stored in the current sketching plane (1-3[1]). Manipulating (switching, creating, etc.) sketching planes will be introduced later.
Sketching Mode v.s. Modeling Mode Tools for sketching are provided in the mode (1-3[2]), while tools for creating and manipulating bodies are provided in the mode (1-10[2]). There are 5 toolboxes available: Draw, Modify, Dimension, Constraints, and Settings. Tools in mode includes (1-10[1]). Some tools are available in both modes, e.g., (1-4[11]).
Look At Face/Plane/Sketch Clicking this tool to rotate the view angle so that you look at the current sketching plane (1-3[3]).
Ruler The ruler (1-3[4, 5]) is to help you obtain a better feeling of the drawing scale. In this book, we always leave the ruler off to make more sketching space.
Plane Coordinate System Every plane has its own coordinate system (1-3[7]); it is also called a local coordinate system. The plane coordinate system will be explained further later.
20
Exercise 1. Arm
Scrolling In case you don't see a tool in a toolbox, scroll down/up to reveal the tool (1-4[2]). There is also a scrolling controller for the .
Tools in Toolbox Circle Line by 2 Tangent
-- Draw a circle, giving the center and the radius (1-4[1, 3-5]). -- Draw a line tangent to two curves (including circles and arcs) (1-7[1, 2]).
Tools in Toolbox Radius Move Display Horizontal Vertical
-- -- -- -- --
Specify a radius dimension by selecting a circle (1-4[6, 8-10]) or an arc (1-8[2]). Move (relocate) a dimension name/value by dragging the name/value (1-4[12, 13]). This tool is to toggle the display of dimension name and the dimension value (1-4[15-17]). In this book, we always turn off the dimension name and turn on the dimension value. Specify a horizontal dimension by first selecting a or a point (or a vertical line) and then a second point (or a vertical line) (1-5[7-10]). Specify a vertical dimension by first selecting a or a point (or a horizontal line) and then a second point (or a horizontal line) (1-5[13, 14]).
Tools in Toolbox Fillet Trim
-- --
Create a fillet by selecting two lines or curves (1-8[1-3]). Trim away unwanted segments (1-9[1-4]).
Auto Constraints P -- The mouse cursor snaps to a point (or the origin) (1-4[4]). R -- The radius is the same as another circle (or arc) (1-4[5]). C -- The mouse cursor is coincident to a line (or an axis) (1-5[4, 6]). Other auto constraint features will be introduced later.
Color Codes Greenish-blue -- Blue -- Red --
Under-constrained (1-8[2]) Fully constrained (fixed in the space) (1-4[9], 1-5[10,14]). Over-constrained
Zoom To Fit Click this tool to fit the entire sketch (in the mode) or entire model (in the mode) into the graphics window (1-4[14]).
Extrude This tool extrude a sketch by a specified depth to create a 3D body (1-10[1-5]). More exercises will be given later.
Isometric View Click the little cyan sphere of the triad will rotate the view into an isometric view (1-10[3]). Other view controls will be introduced later.
Display Plane This tool is to toggle the display of current sketching plane and the sketches it contains (1-10[6]).
Exercise 1a. Structural Analysis of the Arm
Appendix:
Exercise 1a Structural Analysis of the Arm 1a-1 Introduction Although it can be used as a general purpose CAD software, the DesignModeler is particularly designed for creating geometric models to be analyzed (simulated) under the ANSYS environment. The purpose of this exercise is to let the readers understand what it means by analysis (simulation). However, the reader has option to skip this exercise without affect the subsequent learning of geometric modeling. In this exercise, we will perform a static structural analysis for the arm created in Exercise 1. The objective is to find the deformation and stresses under the working loads. The clamping mechanism is entirely made of steel and is designed to withstand a clamping force of 450 lbf [1]. After a structural analysis of the entire mechanism [2] (also see Exercise 17a), the results show shows that, to withstand a clamping force of 450 lbf, the arm is subject to external forces as shown [3] (also see 17a-13). Note that the external forces are in a state of static equilibrium. The analysis for the entire clamping mechanism will be perform in Exercise 17a. In this exercise, we will only perform a analysis on the arm. The purpose is to make sure the stresses are within the allowable stress of the steel, which is 30,000 psi. The analysis task cannot not be performed in DesignModeler. Rather, it is carried out with , another Workbench application program.
[2] This is the deformed structure under the design loads. The wireframe is the underformed configuration. Note that, for visual effects, the deformation has been exaggerated.
281 lbf
[1] The clamping mechanism is designed to withstand a clamping force of 450 lbf.
[3] The external forces on the arm. These forces are calculated according to 17a-13.
264 lbf
77 lbf
407 lbf
126 lbf
187 lbf
21
22
Exercise 1a. Structural Analysis of the Arm
1a-2 Start Up
[1] Launch ANSYS Workbench.
[2] Open the project "Arm," which was saved in Exercise 1.
[3] Double-click to create a analysis system.
[5] And drop here. A link is created, indicating that both share the same data.
[4] Drag ...
[6] Double-click to start up the .
Exercise 1a. Structural Analysis of the Arm
[7] This is the GUI. Note that the model is automatically brought into . By default, the body is assumed to be made of steel.
[8] Make sure the length unit is . If not, select the right unit from the pull-down menu (see [9]).
[9] If the length unit is not , select . Unlike DesignModeler, the units can be changed any time as you like in .
23
24
Exercise 1a. Structural Analysis of the Arm
1a-3 Specify Loads [2] Select .
[3] A object is inserted under the branch.
[1] Click to highlight .
[4] Select this cylindrical face.
[5] Click .
[6] Select .
[7] Type -187 (lbf) for , and 126 (lbf) for .
[8] Select again.
[9] A object is inserted. [10] Select this cylindrical face. [11] Click . [12] Select .
[13] Type 264 (lbf) for , and 281 (lbf) for .
Exercise 1a. Structural Analysis of the Arm
1a-4 Specify Supports [1] Select .
[2] A is inserted.
[3] Select this cylindrical face.
[4] Click .
1a-5 Insert Result Objects
[2] Select .
[1] Click to highlight .
[3] A solution object is inserted under the branch.
25
26
Exercise 1a. Structural Analysis of the Arm
1a-6 Solve the Model
[1] Click .
[4] Select .
[6] For visual effect, the deformation is automatically enlarged 49 times.
[3] The maximum stress is 29,690 psi, slightly below the allowable stress (30,000 psi). Note that the maximum stress can be reduced by increasing the radius of the fillet.
[5] Undeformed shape. [2] Click the Z-axis to rotate the view so that you look into the .
[7] Click to close the window.
[8] Click to animate the deformation.
[9] Click to stop the animation.
Exercise 1a. Structural Analysis of the Arm
1a-7 Save the Project and Exit Workbench
[2] In the , save the project as "Arm-a".
[1] Select . The disappears.
[3] Select to quit from the Workbench.
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28
Exercise 2. Ratchet Stop
Exercise 2 Ratchet Stop
2-1 Introduction
[1] The ratchet wheel.
[2] The ratchet stop is used to control the rotational direction of the ratchet wheel.
The ratchet stop is used to control a ratchet wheel so that the ratchet wheel rotates in a certain direction only [1, 2]. The ratchet wheel will be created in Exercise 3. In this exercise, we'll create a 3D solid model for the ratchet stop. The details of the ratchet stop are shown in the figure below [3]. Note that the coordinate system is also shown in the figure.
R0.56 p: Slo
Y [3] Details of the ratchet stop.
40
0.125
0.1
6
X R0.34 Unit: in. Thickness: 0.125 in.
R0.188 0.57
Exercise 2. Ratchet Stop
2-2 Start Up DesignModeler [1] Launch ANSYS Workbench and create a system (1-2[1-5]).
[2] Double-click cell to start up the DesignModeler. Select as the length unit (1-2[9, 10]).
2-3 Draw a Circle on XYPlane
[3] Draw a circle centered at the plane origin (1-4[1-5]).
[1] Switch to (1-3[2]).
[4] Select tool and specify a radius of 0.188 (in.) for the circle. Remember to turn on the display of dimension value (1-4[15-17]). Also remember to use to move the dimension to a suitable position (1-4[12, 13]).
[2] Rotate to XYPlane view (1-3[3])
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30
Exercise 2. Ratchet Stop
2-4 Draw a Line [5] The line is not bluecolored, meaning it isn't fully defined in the space yet. We now specify an angle dimension for the line.
[2] Select tool and create a length dimension by simply selecting the line segment and move the mouse upward. Specify a dimension value of 0.16 (in.).
[1] Select tool and draw a line roughly like this. [4] Select tool and specify a vertical dimension of 0.125 (in.) (1-5[13-15]).
2-5 Specify an Angle Dimension
[3] Select tool and specify a horizontal dimension of 0.57 (in.) (1-5[7-11]).
[1] To specify an angle dimension, you need to select two lines (or axes). When you select a line (or axis), the end near where you click become the "arrow end" of the line. The angle is then measured from the first line to the second line in a counter-clockwise fashion.
[3] Click the line here near the upper-right end.
[4] Click here to create an angle dimension. Type 40 (degrees) in the . Note that the angle is measured counterclockwise from the first line to the second. Also note that the line is blue-colored now.
[2] Select tool and then click the X-axis on the positive side.
[5] If you made mistakes (click on wrong ends or in a wrong order) and the angle is not what you meant, right-click anywhere in the graphics window to bring up a and choose . Repeat this before you click to locate the angle dimension until the correct angle appears.
Exercise 2. Ratchet Stop
2-6 Draw Arcs [2] Click the upperright end of the line to define an end of the arc.
[4] An arc is created.
[3] Click to define another end roughly here on the circle.
[1] Select tool and then click roughly here to define the center. [5] Select tool and specify a radius dimension of 0.56 in.
[7] Also note that the center of the arc moves to a new location to accommodate the constraint.
[6] Select tool and then select the arc and the circle. A constraint is imposed between the arc and the circle. Note that the arc turns blue.
31
32
Exercise 2. Ratchet Stop
[9] Click the lowerleft end of the line to define an end of the arc.
[10] Click to define another end roughly here on the circle. [8] Select tool again and define the center roughly here.
[11] Select tool and specify a radius dimension of 0.34 in.
[12] Select tool and impose a constraint between the newly created arc and the circle.
Exercise 2. Ratchet Stop
33
2-7 Trim Away Unwanted Segments [1] Select tool and make sure is turned on (1-9[1]). Click here to trim away the arc segment.
[2] The finished sketch.
2-8 Extrude the Sketch to Create the Ratchet Stop [1] Extrude the sketch 0.125 in. to create the ratchet stop (1-10[1-6]).
Wrap Up Close DesignModeler, save the project as "Stop," and exit the Workbench (1-11[1-3]).
34
Exercise 2. Ratchet Stop
2-9 Review Context Menu When you right-click the mouse, a menu pops up. The contents of the menu depends on when and where you right-click the mouse. The menu is thus called the (2-5[5]). Try to right-click anywhere in the graphics area, , or (1-10[2]), to see the contents of the .
Tool This tool can be used for any type of dimension. For a line, the default is to create a dimension (2-4[2]). For a circle or arc, the default is to create a diameter dimension. If the default is not what you want, right-click anywhere in the graphics window to bring up the [1] and choose a dimension type.
Tool To specify an angle dimension, you need to select two lines (or axes). When you select a line (or axis), the end near where you click become the "arrow end" of the line. The angle is then measured from the first line to the second line in a counter-clockwise fashion (2-5[1-4]). If you made mistakes (click on wrong ends or in a wrong order) and the angle is not what you meant, right-click anywhere in the graphics window to bring up the [2] and choose . Repeat this until the correct angle appears before you click to locate the angle dimension (2-5[5]).
[1] This is the when is activated.
Tool This tool draws a line by defining two end points (2-4[1])).
Tool This tool draws an arc by defining its center and two end points (2-6[1-4]).
Tool This tool impose a constraint between two curves or between a line and a curve (2-6[6, 12]).
[1] This is the after you select two lines (or axes) and before you click to create an angle dimension.
Exercise 3. Ratchet
35
Exercise 3 Ratchet Wheel
[1] The ratchet wheel.
3-1 Introduction In this exercise, we'll create a 3D solid model for the ratchet wheel mentioned in Exercise 2 [1]. The details of the ratchet wheel are shown in the figure below [2].
Y
60 15
1.00
[2] Details of the ratchet wheel. X
D0.25
Unit: in. Thickness: 0.25 in.
36
Exercise 3. Ratchet
3-2 Start Up DesignModeler [1] Launch ANSYS Workbench and create a system.
[2] Double-click cell to start up the DesignModeler. Select as the length unit.
3-3 Draw Two Concentric Circles [1] On XYPlane, draw two concentric circles with diameters of 0.25 in. and 1.00 in. respectively.
Exercise 3. Ratchet
37
3-4 Draw Lines with Angle Dimensions [1] Draw a line passing the origin like this.
[2] Specify an angle dimension of 15 degrees. Remember to select the line first and then the axis. Clicking positions are also important (2-5[1-5]).
[3] Draw another line like this. [4] Specify an angle dimension of 60 degrees.
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Exercise 3. Ratchet
3-5 Trim Away Unwanted Segments [1] Draw a circle which passes through an end point of the line. When you define the radius, remember to snap (with a constraint) the end point of the line. The circle serves as a construction (temporary) circle.
[3] After trimming, a single tooth remains.
[2] Trim away unwanted segments. Remember to turn on (1-9[1]).
Exercise 3. Ratchet
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3-6 Duplicate Teeth
[1] Select .
[2] Select these two lines. To select multiple entities, hold Control key while click the entities sequentially. You also can "sweep select" multiple entities, i.e., holding left mouse button while sweep through the entities. After the selection, the entities are highlighted with yellow color.
[3] Right-click anywhere in the graphics window to bring up the , and select . Now the tooth has been copied to a "clipboard."
[4] The tool is automatically activated. Type 15 (degrees) for the , meaning that the rotating angle is 15 degrees.
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Exercise 3. Ratchet
[5] Bring up the , and select . Note that a negative angle is to rotate clockwise.
[6] Bring up the again, and select .
[7] The tooth is rotated 15 degree clockwise (using plane origin as center of rotation) and pasted. [8] Repeat steps [5, 6] four more times. Press to end the tool or choose from the .
Exercise 3. Ratchet
[9] Select again, and select all the teeth, using "sweep select" [2]. From the , select [3].
[10] Type 90 (degrees) for the rotating angle.
[11] Repeat steps [5, 6].
[12] Repeat steps [5, 6] two more times. Press to end the tool or choose from the .
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Exercise 3. Ratchet
3-7 Extrude the Sketch to Create the Ratchet Wheel
[1] Extrude the sketch 0.25 in. to create the ratchet wheel.
Wrap Up Close DesignModeler, save the project as "Ratchet," and exit the Workbench.
Exercise 3. Ratchet
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3-8 Review Selection of Multiple Entities There are several ways to select multiple entities. Two of them are and . Control-Select -- Click the entities sequentially while holding the Control key. Sweep Select -- Hold the left mouse button and sweep through the entities. Box Select -- Select [1], and use mouse to define a box. All entities inside the box are selected.
[1] One way to select multiple entities is to turn on .
and Tools copies the selected entities to a "clipboard." A must be specified using one of the methods in the (3-6[3]). After completing the tool, the tool is automatically activated. pastes the entities in the "clipboard" to the graphics window. The pasting location corresponds to the specified in the tool. To define the pasting location, you either click on the graphics window or choose from the (3-6[6]). Many options also can be chosen from the (3-6[5]), where the rotating angle and the scaling factor can be specified with the tool (3-6[4]). A positive rotating angle is to rotate counter-clockwise.
Tool is equivalent to a followed by a .
Ending a Tool You can press to end a tool (3-6[8, 12]). Besides, the often provides an option to end a tool (3-6[5, 6]).
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Exercise 4. Cover Plate
Exercise 4 Cover Plate
4-1 Introduction In this exercise, we'll create a 3D solid model for a cover plate, of which the details are shown in the figure below [2].
2 × R0.188
2 × D0.201
8 × R0.15
0.25
Y
0.376 0.312
2.00
0.312
1.25
[1] Details of the cover plate.
0.25
0.75
6 × R0.06
X Unit: in. Thickness: 0.046 in.
0.562 1.50
Exercise 4. Cover Plate
4-2 Start Up DesignModeler [1] Launch ANSYS Workbench and create a system.
[2] Double-click cell to start up the DesignModeler. Select as the length unit.
4-3 Draw Circles
[2] Draw another circle with the same diameter. Make sure an appears when you define the radius (1-5[5]).
[3] Use to specify a dimension of 0.376 in.
[4] Use to specify a dimension of 2 in.
[1] On XYPlane, draw a circle centered at the origin and with a diameter of 0.201 in.
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Exercise 4. Cover Plate
[6] Draw a concentric circle with the same radius. Make sure an appears when you define the radius.
[5] Draw a concentric circle with a radius of 0.188 in.
4-4 Draw Rectangles and Lines
[1] Select and draw a rectangle with dimensions a shown.
Exercise 4. Cover Plate
[2] Select and draw three segments like this. Select from the after you define the fourth point. Note that the three segments are either horizontal or vertical, therefore make sure an or a appears before clicking. Specify the dimensions as shown.
[4] Trim away this extra segment. [3] Select again and draw a line like this. Note that the two end points coincide with the Y-axis. [5] Trim away this extra segment.
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Exercise 4. Cover Plate
[7] Trim away this segment. [6] Use again to draw a vertical line and specify a horizontal dimension as shown.
[8] Trim away this segment.
[9] Trim away this segment.
Exercise 4. Cover Plate
4-5 Draw Fillets [2] Create 6 fillets with the same radius (1-8 [2]).
[1] Select and type 0.06 (in.) for the .
[3] Create a radius dimension for anyone of the fillets (1-8[3]).
[5] Create 4 fillets with the same radius.
[4] Select again and type 0.15 (in.) for the .
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Exercise 4. Cover Plate
[6] With tool still activated, create this fillet by clicking the horizontal line and the circle. Note that the horizontal line is automatically trimmed.
[7] Repeat the last step to create this fillet.
[8] Use to re-create the trimmed segment.
[9] Repeat the last step to re-create this line.
Exercise 4. Cover Plate
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[12] Create a radius dimension for anyone of the 8 fillets.
[10] Use to create this fillet (with the same radius as before) by clicking the horizontal line and the circle.
[11] Repeat the last step to create this fillet.
4-6 Trim Away Unwanted Segments
[1] Select and turn on , then trim away this segment.
[2] And this segment.
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Exercise 4. Cover Plate
[3] The final sketch.
4-7 Extrude the Sketch to Create the Cover Plate
[1] Extrude the sketch 0.046 in. to create the cover plate.
Wrap Up Close DesignModeler, save the project as "Cover," and exit the Workbench.
Exercise 4. Cover Plate
4-8 Review Draws a rectangle by defining two diagonally opposite points. The edges of the rectangle are either horizontal or vertical. To draw a rectangle at an arbitrary orientation, please use .
This tool allows you to draw a series of connected lines, called a polyline. The polyline can be closed or open. After defining the last point, choose or from the .
Auto Constraints H V
-- --
Horizontal Vertical
Note: For a comprehensive description of sketching tools, please refer to the following ANSYS on-line reference: ANSYS Help System//DesignModeler User Guide//2D Sketching
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Section B. Part Modeling
Section B Part Modeling
As mentioned in the opening of Section A, many parts can be created by a two-step operation: drawing a 2D sketch on a plane and then generate a 3D body by extrusion, revolution, sweeping, or skin/lofting. A more complicated part often can be viewed as a series of the two-step operations; each two-step operation either add material to the existing body or cut material from the existing body. The exercises in Section B are designed to introduce the 3D modeling techniques for more complicated parts.
Exercise 5. Crank
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Exercise 5 Crank
5-1 Introduction In this exercise, we'll create a 3D solid model for a crank, of which the details are shown in the figure below. Note that a global coordinate system is set up and shown in the figure. The crank model can be viewed as a series of three two-step operations; each involves drawing a sketch on XYPlane and then extrude the sketch to generate a material. The materials are either add to the existing body or cut from the existing body.
Y
Y 2 × D10 2 × R10
75
Unit: mm.
R10
X
Z
R22 D30 D20
65
8 20
56
Exercise 5. Crank
5-2 Start Up DesignModeler [3] Select as the length unit. [1] Launch ANSYS Workbench and create a system.
[2] Double-click cell to start up DesignModeler.
5-3 Draw a Sketch on XYPlane
[1] On XYPlane, draw 5 circles and 4 tangent lines (using ) like this. Specify the dimensions.
Exercise 5. Crank
[3] Trim away these three arc segments.
[2] Use to draw a fillet with a radius of 10 mm.
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Exercise 5. Crank
5-4 Extrude to Create a Solid Body [1] The active plane.
[2] The active sketch.
[10] Click to turn off the plane display.
[9] Click . [3] Click . [5] An object is inserted in the model tree.
[8] Click the small cyan sphere to rotate the view into an isometric view.
[4] It automatically switches to .
[6] Click . The active sketch is automatically taken for .
[7] Type 8 (mm) for . [11] The displays a tree structure for the geometry model, called .
[13] Under the XYPlane, we've created a sketch (Sketch1)
[14] The uses as the base geometry. [12] Click all the plus signs to expand the model tree.
[15] This is the body we've created so far.
Exercise 5. Crank
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5-5 Create a New Sketch on XYPlane
[2] A new sketch (Sketch2) is created. Note that, for the first sketch of a plane, you don't need to explicitly click . However, for additional sketches on the same plane, you need to click . Remember that the drawing entities always belong to the active sketch.
[1] Click .
[4] Click .
[5] Click to turn off the solid model display.
[3] Click to switch to .
[6] Draw a circle with a diameter of 30 mm. This is the only entity in . Note that both Sketch1 and Sketch2 are on the same plane (XYPlane).
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Exercise 5. Crank
5-6 Add Material to the Existing Body [2] Click .
[1] Click .
[4] The default is .
[3] Type 20 (mm).
[5] Click .
[8] Click the plus sign to expand .
[6] The newly created material is simply a cylinder; it adds to the existing body to form a single body.
[7] is added under XYPlane.
[9] uses as the base geometry. The is simply a cylinder.
[10] The body after adding material.
Exercise 5. Crank
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5-7 Create Another New Sketch on XYPlane
[2] A new sketch (Sketch3) is created.
[1] Click .
[4] Click .
[5] Click to turn off the solid model display.
[3] Click to switch to .
[6] Draw a circle with a diameter of 20 mm. This is the only entity in . Note that all three sketches are on the same plane (XYPlane).
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Exercise 5. Crank
5-8 Extrude to Create a Third Simple Body [2] Click .
[1] Click .
[3] Select .
[4] Select . [5] Click .
[7] is added under XYPlane.
[8] Click the plus sign to expand .
[6] The newly created material is simply a cylinder; The material is cut from the existing body.
Wrap Up Close DesignModeler, save the project as "Crank," and exit the Workbench.
[9] uses as the base geometry. The is simply a cylinder.
[10] The body after cutting material.
Exercise 5. Crank
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5-9 Review and A sketch must be created on a plane; each plane, however, may contain multiple sketches. In the beginning of a DesignModeler session, three planes are automatically created: XYPlane,YZPlane, and ZXPlane. You can create new planes and new sketches as many as needed.
and The currently active plane and active sketch are shown in the toolbar (5-4[1, 2]). New sketches are created on the active plane, and new drawing entities are created on the active sketch. You may change the active plane or active sketch by selection from the pull-down list, or simply clicking the names on the model tree.
Modeling Mode In the modeling mode (5-4[4]), several modeling tools become available, including Extrude, Revolve, Sweep, Skin/Loft, Thin/Surface, Blend, Chamfer, Point, etc. In addition, a is displayed.
Model Tree (5-4[11]) contains an outline of the model tree, the data structure of the geometric model. Each branch of the tree is called an object, which may contain one or more objects. At the bottom of the model tree is a part branch, which is the only object that will be exported to . By right-clicking an object and selecting a tool from the context menu, you can operate on the object, such as delete, rename, duplicate, etc. The order of the objects is relevant. renders the geometry according to the order of objects in the model tree. New objects are normally added one after another. If you want to insert a new object BEFORE an existing object, right-click the existing object and select from the context menu. After insertion, will re-render the geometry.
and With operation mode, the created material adds to the existing active body (i.e., they form a union). With operation mode, the material is cut from the existing active body. An active body is one that is not frozen (to be defined later).
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Exercise 6. Geneva Gear Index
Exercise 6 Geneva Gear Index
6-1 Introduction In this exercise, we'll create a 3D solid model for a Geneva gear index, of which the details are shown in the figure below. Note that a global coordinate system is set up and shown in the figure.
Y
Y
5× 0
5 × R0.63
.2 Unit: in.
29
1.5
X
Z
D0.25 D0.5
D2.47 D1.25 0.25 0.44
Exercise 6. Geneva Gear Index
6-2 Start Up DesignModeler [1] Launch ANSYS Workbench and create a system.
[2] Double-click cell to start up the DesignModeler. Select as the length unit.
6-3 Draw a Sketch on XYPlane
[2] draw two lines, each connects the origin to an end point of the arc.
[1] On XYPlane, use to draw an arc centered at the origin and with a radius of 1.235 (in.) like this.
[5] draw two circles centered at end points of the new arc and with the same radius of 0.1 (in.).
[3] Specify an angle dimension of 72 (degrees) for the sector.
[4] Use to draw another arc with a radius of 0.625 (in.) like this.
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Exercise 6. Geneva Gear Index
[7] Draw a line connecting the upper circle to the outer arc like this. The line is parallel to the adjacent line, therefore make sure a (indicating parallel auto constraint) appears before clicking.
[6] Draw a line connecting the lower circle to the outer arc like this. The line is horizontal, therefore make sure an appears before clicking. [9] Apply a on the upper circle and the parallel line.
[8] Apply a on the lower circle and the horizontal line.
Exercise 6. Geneva Gear Index
[10] Draw a line starting from the origin like this. Then, make the outer arc symmetric about the newly created line. To do this, select , and then subsequently click the line and the two end points of the arc.
[11] Use to specify a length dimension of 1.529 (in.). [12] Use to draw an arc centered at one end of the new line. Specify the radius dimension of 0.63 (in.).
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Exercise 6. Geneva Gear Index
[13] Trim away unwanted segments. This is the sketch after trimming. Note that, although the the sketch is no more blue-colored, all the dimensions are not changed.
6-4 Extrude to Generate 1/5 of the Gear Index
[1] Extrude the sketch 0.25 in.
Exercise 6. Geneva Gear Index
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6-5 Duplicate the Body Circularly [4] Select the body.
[1] Select from the pull-down menu.
[2] In the , select for . [3] Click the yellow area to bring up buttons.
[5] And click .
[9] Type 4 for .
[6] Click the yellow area to bring up buttons. [8] And click . [7] Select this edge.
[10] Click .
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Exercise 6. Geneva Gear Index
6-6 Create the Hub [4] Click .
[1] Select from the pull-down menu.
[2] Type 0.44 (in.) for the .
[3] Type 0.25 (in.) for the .
[9] Click . [5] Select again.
[6] Select for .
[7] Type 0.44 (in.) for the .
[8] Type 0.125 (in.) for the .
Wrap Up Close DesignModeler, save the project as "Geneva," and exit the Workbench.
Exercise 6. Geneva Gear Index
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6-7 Review Auto Constraints: It is applicable to a line, indicating that the line is parallel to another line in the same plane (6-3[7]).
Sketching Tools: It can be applied on two edges (lines or curves), one of them must be a curve, to make them tangent to each other (6-3[8, 9]).
This tool allows you to create copies bodies in three types of pattern: Linear, Circular, and Rectangular (6-5).
This tool creates a cylinder by specifying its origin, axis, and radius (6-6). The origin and axis are defined by referring to the active plane coordinate system (1-12).
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Exercise 7. Yoke
Exercise 7 Yoke
7-1 Introduction The yoke is a part of a universal joint [1]. In this exercise, we'll create a 3D solid model for the yoke, of which the details are shown in the multiview drawings below. Note that a global coordinate system is also shown in the figure.
[1] The yoke is a part of a universal joint. X
Z
D1.20 Y
Y
Unit: in.
3.55
R1.00
Z 1.50
X
D0.75 2 × 0.75
R1.00
Exercise 7. Yoke
7-2 Start Up DesignModeler [1] Launch ANSYS Workbench and create a system.
[2] Double-click cell to start up the DesignModeler. Select as the length unit.
7-3 Create a U-Shape Body
[2] Use tool to draw a 3-segment polyline, starting from this point.
[1] On XYPlane, use tool to draw two concentric arcs. Specify the radius dimensions (1.00 in. and 1.75 in. respectively).
[5] Click the last point and then select from the . If the last segment is not vertical, use to make it vertical.
[6] Use to specify a length of 2.50 (in.). [3] Click the second point. Make sure the first segment is vertical.
[4] Click the third point. Make sure the second segment is horizontal.
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Exercise 7. Yoke
[7] Draw two vertical lines.
[8] Trim away this segment.
[12] Click . [9] Click .
[10] Select .
[11] Type 1 (in.) for . Note that, the sketch is extruded by 1.0 in. for both sides of XYPlane, therefore the total depth is 2.0 in.
Exercise 7. Yoke
7-4 Create Rounds
[1] Select from the toolbar.
[2] Controlselect these 4 edges.
[4] Type 1 (in.) for .
[5] Click .
[3] Click .
7-5 Create Holes
[1] Select from the pull-down menu.
[3] Click .
[2] Click to bring up buttons, then select from the model tree and click . Now the global Y-axis becomes local X-axis, and the global Zaxis becomes local Y-axis. The origin and the axis are defined using the local (plane) coordinate system.
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Exercise 7. Yoke
7-6 Create Shaft
[1] Click to create a new plane.
[7] The new plane become active plane.
[6] Click .
[2] A new plane (Plane4) is inserted into the model tree. [3] Click to bring up buttons, then select from the model tree and click . Now the global Z-axis becomes local X-axis, and the global X-axis becomes local Y-axis.
[4] Select for . Note that it refers to the local Z-axis.
[5] Type 3.55 (in.) for .
[9] The local coordinate system of the new plane. Note that, in a local coordinate system, the Workbench also uses RGB colors to represent XYZ axes respectively.
[8] The global coordinate system. Note that the Workbench uses RGB colors to represent XYZ axes respectively.
Exercise 7. Yoke
[3] Click to turn off model display.
[2] Click to look at .
[4] Draw a circle with a diameter of 1.2 (in.).
[1] Click to switch to the .
[5] Click .
[6] Select for . Now, the extrusion direction is the -Z direction.
[7] Select . Now the sketch will be extruded up to the next face.
Wrap Up Close DesignModeler, save the project as "Yoke," and exit the Workbench.
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[8] Click .
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Exercise 7. Yoke
7-7 Review Extrude Direction There are four options you can choose for the extrusion direction: , , , and . In case, the extrusion direction is the Z-direction of the sketching plane. When is selected, the extrusion direction reverses to the -Z-direction (7-6[6]). For , the extrusion is along both +Z and -Z directions with the same depth (defined by ) (7-3[10]). For , the extrusion is along both +Z and -Z directions with the different depths (defined by and ).
This tool can be used to place rounds or fillets on a body (7-4). The fillets are specified on edges, while the rounds can be specified on edges or faces. When faces are specified for rounds, the rounds are placed on the enclosing edges.
Create New Planes from Existing Planes There are many ways to create a new plane [1]. Creating new plane from an existing plane (7-6[1-9]) involves selecting the existing plane and then transforming the existing plane to a new position and orientation.
[1] There are many ways to create a plane.
Exercise 8. Support
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Exercise 8 Support 8-1 Introduction The support is a part of the clamping mechanism mentioned in Exercise 1 [1]. In this exercise, we'll create a 3D solid model for the support, of which the details are shown in the multiview drawings below. Note that a global coordinate system is also shown in the figure.
X [1] The support is a part of a clamping mechanism. 0.125 0.375
0.375
0.375 1.250
0.219
Z
Y
0.250
0.750
R0.313 Unit: in.
2 × R0.100 0.250
:4 pe Slo
1.250
5
R0.156
Y
6 × D0.25
0.375
Z
1.250 0.625
0.875
X
2.500
0.125
1.000
R0.100
80
Exercise 8. Support
8-2 Start Up DesignModeler [1] Launch ANSYS Workbench and create a system.
[2] Double-click cell to start up the DesignModeler. Select as the length unit.
8-3 Create Vertical Plate
[3] Use to draw a polyline starting from roughly here.
[1] On XYPlane, draw three circles of the same radius. Specify their locations (two horizontal dimension of 1.25 and one vertical dimension of 1.25)
[2] Specify a diameter of 0.25 in. for any one of the circles.
[6] Click the fourth point, making sure the last segment is vertical. Then select from the .
[5] Click the third point, making sure the last segment is horizontal.
[4] Click the second point, making sure the last segment is vertical. [7] Specify all dimensions so that all entities become blue-colored: length dimensions of 2.50 and 0.625; a horizontal dimension of 0.375, a vertical dimension of 0.875, and an angle dimension of 45 degrees.
Exercise 8. Support
[8] Draw two more circles, specify their radii (0.156 and 0.313) and locations (horizontal dimensions of 0.219 and 0.250; vertical dimensions of 0.25 and 0.75)
[9] Trim away unwanted segments.
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Exercise 8. Support
[10] Draw two fillets with the same radius of 0.1 in.
[11] Click .
[13] Click .
[12] Type 0.125 (in.) for .
Exercise 8. Support
8-4 Create Horizontal Plate
[7] Click ; a is created.
[1] Click .
[3] The default is .
Y
X
[2] Select .
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[4] Click the yellow area to bring up buttons.
Z
[5] Click this face at a location near this circle. A plane coordinate system shows up like this (the X axis points to global -X axis). Note that the location you click determines the origin and the axes of the plane coordinate system. If the coordinate system is not like this, simply re-click again until it is correct.
[6] Click .
[10] Click to turn of the model display.
[8] Click to switch to .
[12] Draw a rectangle like this. Note that three sides of the rectangle coincide with plane's outline. Specify a length dimension of 0.125 in. so that the rectangle become blue-colored.
[9] Click to look at .
[11] This is ; it is called an since it includes an outline. The outline is not part of a sketch but can be used as references.
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Exercise 8. Support
[13] Click . [15] Click .
[14] Type 1 (in.) for .
8-5 Create Holes on the Horizontal Plate [1] Click .
[2] Select .
[3] Click the yellow area to bring up buttons.
[5] Click .
Z
Y
[4] Click this face at a location near this corner so that the plane coordinate system is like this (the X axis points to global X axis). Remember, if the coordinate system is not like this, simply reclick again until it is correct.
X
[6] Click ; a is created.
Exercise 8. Support
[9] Click to turn of the model display.
[11] Draw three circles of the same diameter (0.25 in.) and specify their positions (horizontal dimensions of 0375, 0.375, and 1.25; vertical dimensions of 0.375, 0.375, and 0.125)
[8] Click to look at .
[10] This is ; it includes an outline.
[7] Click to switch to .
[16] Click . [12] Click .
[13] Select . [14] The automatically becomes .
[15] Select .
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Exercise 8. Support
8-6 Create the Round
[1] Select from the toolbar.
[2] Click this edge.
[4] Type 0.1 (in.) for .
[3] Click .
[5] Click .
Wrap Up Close DesignModeler, save the project as "Support," and exit the Workbench.
Exercise 8. Support
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8-7 Review Create New Planes From Faces You can create a new plane from an existing face (8-4[1-7]). There are subtypes to choose: and . The only difference is that a doesn't include the outline of the face. In either subtype, the plane coordinate system is determined according to how you click the face. The origin is usually located at the closest corner point or the center of a circle (or an arc); The Z-axis always points out of the face; The X-axis is usually parallel to the closest edge. An outline plane include the outline of the face (8-4[11]). The outline is not part of a sketch but can be used as references (datum). Without the outline, the only references are two exes (X-axis and Y-axis of the plane). However, you can copy the outline (or part of the outline) into a sketch, using the sketching tool .
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Exercise 8a. Structural Analysis of the Support
Appendix:
Exercise 8a Structural Analysis of the Support
8a-1 Introduction In this exercise, we will perform a static structural analysis for the support created in Exercise 8. The objective is to find the deformation and the stresses under the working loads, and make sure the stresses are within the allowable level (30,000 psi). As mentioned in Exercise 1a, the clamping mechanism is entirely made of steel and is designed to withstand a clamping force of 450 lbf [1]. After a structural analysis of the entire mechanism [2] (which is performed in Exercise 17a), the results show shows that, to withstand a clamping force of 450 lbf, the support is subject to external forces as shown [3] (also see 17a-4). Note that the holes on the horizontal plates are fixed to the ground [4]. The analysis task will be carried out with .
[2] This is the deformed structure under the design loads. The wireframe is the underformed configuration.
[1] The clamping mechanism is designed to withstand a clamping force of 450 lbf.
380 lbf
62 lbf
[3] The external force on the arm. See 17a-14.
163 lbf 380 lbf [4] The horizontal plates are fixed to the ground.
Exercise 8a. Structural Analysis of the Support
8a-2 Start Up
[1] Launch ANSYS Workbench.
[2] Open the project "Support," which was saved in Exercise 8.
[3] Double-click to create a analysis system.
[5] And drop here. A link is created, indicating that both share the same data.
[4] Drag ...
[6] Double-click to start up the .
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Exercise 8a. Structural Analysis of the Support
8a-3 Specify Loads
[7] Make sure the length unit is (1a-2[8, 9]). [2] Select .
[1] Click to highlight .
[4] Click .
[5] Select .
[6] Type -380 (lbf) for , and 62 (lbf) for .
[3] Select this cylindrical face.
Exercise 8a. Structural Analysis of the Support
[7] Select again.
[8] Select this cylindrical face.
[9] Click . [10] Select .
[11] Type 380 (lbf) for , and 163 (lbf) for .
8a-4 Specify Supports
[2] Control-select the three cylindrical faces on the horizontal plate.
[1] Select .
[3] And control-select this face.
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Exercise 8a. Structural Analysis of the Support
[4] Click . Totally 5 faces are set to .
[6] Control-select the four cylindrical faces on the vertical plate.
[7] Click .
[8] Type 0 (in.) for .
[5] Select
