Advanced Assembly

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(1)Pro/ENGINEER: Advanced Assembly Design & Management Wildfire RA-T-251-WF-02. Delivered to you by:. At ASCENT, we strive to produce training materials of the highest quality. If you have any comments or suggestions regarding this training manual, please contact us: [email protected].

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(3) ASCENT - Center for Technical Knowledge™ Advanced Assembly Design and Management Wildfire PRINTING HISTORY Document Number. Date. Description. RA-T-251-WF-01 RA-T-251-WF-02. 05/05/03 05/20/03. Initial Printing for Wildfire Release Printing for Wildfire Release. Prepared and Produced by ASCENT - Center for Technical Knowledge™ 5285 Solar Dr. Mississauga, Ontario Canada L4W 5B8 www.ASCENTed.com ASCENT - Center for Technical Knowledge™ is a division of RAND Worldwide™, providing custom developed knowledge products and services for leading engineering software applications. ASCENT is focused on specializing in the creation of education programs that incorporate the best of classroom learning and technology-based training offerings.. © ASCENT - Center for Technical Knowledge™, 2003 Printed in the United States of America, all rights reserved. No part of this manual may be reproduced in any form by any photographic, electronic, mechanical or other means or used in any information storage and retrieval system without the written permission of ASCENT, a division of Rand Technologies of Michigan, Inc...

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(5) ASCENT - Center for Technical Knowledge™. Table of Contents Table of Contents .............................................................................. i Chapter 1 Introduction to Assembly .......................................... 1-1 1.1. Assembly Design Philosophies................................... 1-3 Default Datum Planes................................................ 1-3 Parts and Subassemblies .......................................... 1-4 Skeleton Models ........................................................ 1-4 Assembly Features .................................................... 1-4 Parts in Assembly Mode ............................................ 1-4 Assembly Relations ................................................... 1-5 Assembly Regeneration............................................. 1-5. 1.2. Component Placement ................................................. 1-6 Constraints and Offsets ............................................. 1-7 References ................................................................ 1-8. 1.3. Revision Tools............................................................... 1-9 Edit Definition............................................................. 1-9 Edit References ......................................................... 1-9 Reorder.................................................................... 1-10 Insert Mode.............................................................. 1-11. 1.4. Repeating Components.............................................. 1-12 General Steps.......................................................... 1-12 Start the Repeat operation ................................ 1-12 Modify constraints and references .................... 1-13 Complete the repeat operation.......................... 1-13. 1.5. Assembly Design Approach ...................................... 1-14. 1.6. Assembly File Management ....................................... 1-15 Rename ................................................................... 1-15 Save a Copy ............................................................ 1-16 Backup..................................................................... 1-17. Exercise 1a Assembly Constraints I .................................. 1-19 Exercise 1b Assembly Constraints II ................................. 1-31 Chapter 2 Skeleton Models ......................................................... 2-1 2.1. Skeleton Models............................................................ 2-3 Parent/Child Relationships ........................................ 2-3 Incorporating Motion .................................................. 2-4 Spatial Claims............................................................ 2-5 Geometry Creation .................................................... 2-6 General Steps............................................................ 2-7 Create a skeleton model ..................................... 2-7. Pro/ENGINEER: Advanced Assembly Design and Management. i.

(6) ASCENT - Center for Technical Knowledge™. Define the skeleton geometry ............................. 2-8 2.2. Skeleton Properties ...................................................... 2-9. Exercise 2a Creating a Skeleton part................................. 2-11 Chapter 3 Packaging.................................................................... 3-1 3.1. Packaging ...................................................................... 3-3 General Steps............................................................ 3-3 Assemble the component.................................... 3-3 Position the component in the assembly............. 3-4 Move Options................................................. 3-4 Free Form Packaging .................................... 3-7. 3.2. Finalizing Components ................................................ 3-8 Snap by Proximity...................................................... 3-8. Exercise 3a Packaging Assembly Components ............... 3-11 Chapter 4 Assembly Duplication Tools ..................................... 4-1. ii. 4.1. Pattern Tables ............................................................... 4-3 General Steps............................................................ 4-3 Start the creation of the pattern........................... 4-4 Set the pattern type............................................. 4-4 Convert a dimension pattern to a table.......... 4-4 Select the driving dimensions ............................. 4-5 Edit the table ....................................................... 4-5 Save the table to disk, if necessary..................... 4-6 Modify the pattern table, if necessary ................. 4-7. 4.2. Reference Patterns ....................................................... 4-8 General Steps............................................................ 4-8 Start the creation of the pattern........................... 4-8 Set the pattern type............................................. 4-9 Complete the pattern........................................... 4-9. 4.3. Fill Patterns ................................................................. 4-10 General Steps.......................................................... 4-10 Start the creation of the pattern......................... 4-11 Set the pattern type........................................... 4-11 Define the fill area ............................................. 4-11 Define the fill options......................................... 4-12 Remove members of pattern, if necessary ....... 4-13. 4.4. Copying........................................................................ 4-14 General Steps.......................................................... 4-14 Start the copy operation .................................... 4-14 Select the reference coordinate system............ 4-14 Select the component(s) to be copied............... 4-15 Define the first copy direction............................ 4-15 Define additional copy directions ...................... 4-16 Pro/ENGINEER: Advanced Assembly Design and Management.

(7) ASCENT - Center for Technical Knowledge™. Modify the instances, as necessary .................. 4-17 Exercise 4a Copy and Pattern ............................................ 4-19 Chapter 5 Assembly Family Tables ............................................ 5-1 5.1. Creating Assembly Family Tables............................... 5-3 General Steps............................................................ 5-3 Open the family table editor ................................ 5-4 Add items to the family table ............................... 5-4 Add instances to the family table......................... 5-6 Manipulate the family table instances ................. 5-7 Component Manipulation ............................... 5-7 Pattern ........................................................... 5-8 Controlling Lower Level Items...................... 5-10 Create a multi-level family table, if necessary ... 5-10 Verify the family table ........................................ 5-11 Retrieve an instance.......................................... 5-11 Instance Index ......................................................... 5-12. 5.2. Modifying Family Tables ............................................ 5-13 Modifying family tables ............................................ 5-13 Modifying non-family tables ..................................... 5-14 Adding components to the generic model ............... 5-14 Adding components to an instance.......................... 5-15 Deleting components from an instance ................... 5-16 Deleting components from the generic .................... 5-17. Exercise 5a Assembly Family Tables ................................ 5-19 Chapter 6 Assembly Management.............................................. 6-1 6.1. Component Display Styles........................................... 6-3 General Steps............................................................ 6-4 Open the View Manager...................................... 6-4 Create a display style .......................................... 6-4 Define display settings for the components......... 6-5 Complete the display style .................................. 6-6 Edit the display style, as necessary .................... 6-7. 6.2. Layers in Assembly Mode ............................................ 6-8 General Steps............................................................ 6-8 Access the layer tree........................................... 6-8 Create the layer................................................. 6-10 Add features or components to the layer .......... 6-11 Add part level features to a layer ................. 6-12 Set and save the display status of the layer...... 6-13 Blank ............................................................ 6-13 Unblank........................................................ 6-13 Isolate .......................................................... 6-13 Hidden.......................................................... 6-13. Pro/ENGINEER: Advanced Assembly Design and Management. iii.

(8) ASCENT - Center for Technical Knowledge™. Layer Info..................................................... 6-14 Modify the layer, as necessary.......................... 6-15 Default Layers.............................................. 6-15 6.3. Suppress and Resume ............................................... 6-16 Select the items to be suppressed .................... 6-16 Suppress the selected items ............................. 6-17 Resume items as necessary ............................. 6-18. 6.4. Restructure.................................................................. 6-20 General Steps.......................................................... 6-20 Start the restructuring operation........................ 6-21 Select the component to move.......................... 6-21 Select the target component ............................. 6-21 Continue moving components as necessary .... 6-21 Break external references as necessary........... 6-22. Exercise 6a Layers .............................................................. 6-23 Exercise 6b Restructure...................................................... 6-33 Chapter 7 Designing in Context.................................................. 7-1. iv. 7.1. Introduction to External References ........................... 7-3. 7.2. External References for the Current Assembly ......... 7-4 General Steps............................................................ 7-4 Activate the reference control ............................. 7-4 Define the Accessible tab options ....................... 7-5 Define the Shared tab options............................. 7-6 Complete the settings ......................................... 7-7. 7.3. Global External References ......................................... 7-8 General Steps............................................................ 7-8 Activate the reference control ............................. 7-8 Define the Object tab options.............................. 7-9 Define the Geometry tab options ........................ 7-9 Define the Selection tab options ....................... 7-10 Complete the settings ....................................... 7-11. 7.4. Global Reference Viewer............................................ 7-12. 7.5. Creating Parts in Assembly ....................................... 7-14 General steps .......................................................... 7-14 Start the creation of a new component ............. 7-15 Select the type of component............................ 7-15 Define the creation options ............................... 7-16 Create geometry or assemble components ...... 7-17. 7.6. Creating Assembly Features ..................................... 7-19 General Steps.......................................................... 7-20 Create the assembly feature ............................. 7-20 Set intersection option....................................... 7-20. Pro/ENGINEER: Advanced Assembly Design and Management.

(9) ASCENT - Center for Technical Knowledge™. 7.7. Mirroring Components ............................................... 7-23 General Steps.......................................................... 7-23 Create a temporary assembly ........................... 7-24 Start the mirror operation .................................. 7-24 Select the type of mirror .................................... 7-24 Select the component(s) to mirror ..................... 7-25 Select the reference for mirroring...................... 7-25 Complete the component .................................. 7-26 Mirroring Subassemblies ......................................... 7-27. Exercise 7a Assembly Features ......................................... 7-29 Exercise 7b Assembly parts ............................................... 7-35 Exercise 7c Mirroring Components ................................... 7-53 Chapter 8 Distributing Design Information................................ 8-1 8.1. Merge & Cut Out............................................................ 8-3 General Steps............................................................ 8-3 Create an assembly ............................................ 8-4 Start the Merge or Cut Out operation .................. 8-4 Select the references .......................................... 8-5 Merge......................................................................... 8-5 Cut Out ...................................................................... 8-5 Review the models .............................................. 8-6. 8.2. Part Intersections.......................................................... 8-7 General Steps............................................................ 8-7 Create an assembly ............................................ 8-7 Create the new component ................................. 8-8 Select the references .......................................... 8-8 Review the model................................................ 8-8. 8.3. Copy Geometry Features ........................................... 8-10 General steps .......................................................... 8-11 Create or open an assembly ............................. 8-12 Set the reference control ................................... 8-12 Start the creation of the feature......................... 8-12 Select the entities to copy, as necessary .......... 8-13 Define options for the feature ............................ 8-15 Complete the feature......................................... 8-16. 8.4. External Copy Geometry Feature ............................. 8-17. 8.5. Inheritance Features ................................................... 8-18 General Steps.......................................................... 8-19 Create or open an assembly ............................. 8-20 Start creation of the inheritance feature ............ 8-20 Define the base model ...................................... 8-20 Define the optional elements, as necessary...... 8-21 Complete the feature......................................... 8-24. Pro/ENGINEER: Advanced Assembly Design and Management. v.

(10) ASCENT - Center for Technical Knowledge™. Exercise 8a Assembly Merge ............................................. 8-25 Exercise 8b Copy Geometry ............................................... 8-31 Chapter 9 Simplified Representations ....................................... 9-1 9.1. Simplified Representations.......................................... 9-3. 9.2. System-Defined Simplified Representations ............. 9-5 General Steps............................................................ 9-5 Open the View Manager ..................................... 9-5 Select the simplified representation .................... 9-6 Master Rep .................................................... 9-6 Symbolic Rep................................................. 9-6 Graphics Rep................................................. 9-6 Geometry Rep ............................................... 9-6. 9.3. User-Defined Simplified Representations .................. 9-7 General Steps............................................................ 9-7 Open the View Manager ..................................... 9-7 Create a new simplified representation............... 9-7 Define the representation settings ...................... 9-8 Manual Selection ........................................... 9-8 Definition Rules.............................................. 9-9 Update the simplified representation................. 9-11 Redefine the simplified representation.............. 9-11. 9.4. Zones .......................................................................... 9-12 General Steps.......................................................... 9-12 Start the creation of the zone ............................ 9-12 Create a new zone ............................................ 9-13 Define the zone regions .................................... 9-13 Redefine the zone, as necessary...................... 9-15 Use the zone in a simplified rep ........................ 9-16. 9.5. Envelopes .................................................................... 9-17 General Steps.......................................................... 9-17 Start the creation of the envelope ..................... 9-18 Create a new envelope ..................................... 9-18 Select the components to be represented ........ 9-19 Create the envelope model ............................... 9-19 Use the envelope in a simplified rep ................. 9-20. Exercise 9a Simplified Reps I ............................................. 9-21 Exercise 9b Simplified Reps II............................................ 9-29 Chapter 10 Interchange Assemblies ........................................ 10-1 10.1. vi. Functional Component............................................... 10-3 General Steps.......................................................... 10-3 Start creation of the interchange assembly....... 10-3 Assemble the components................................ 10-4 Pro/ENGINEER: Advanced Assembly Design and Management.

(11) ASCENT - Center for Technical Knowledge™. Specify reference tags....................................... 10-4 Auto Tagging ........................................................... 10-6 Manual Tag Creation ............................................... 10-6 Complete the interchange assembly ................. 10-8 Replace components with functional interchange components....................................................... 10-8 10.2. Simplify Components ............................................... 10-10 General Steps........................................................ 10-10 Start the creation of the interchange assembly 10-10 Assemble a functional component .................. 10-10 Assemble or create the first component.......... 10-11 Assemble ................................................... 10-12 Create ........................................................ 10-12 Complete the first association ......................... 10-12 Add functional components, as necessary...... 10-13 Add simplified components, as necessary ...... 10-14 Complete the interchange assembly ............... 10-16 Substitute for the simplified component .......... 10-16. 10.3. Case Studies............................................................. 10-17 Example 1.............................................................. 10-17 Example 2.............................................................. 10-18 Example 2.............................................................. 10-19. Exercise 10a Functional Interchange Assemblies I........ 10-21 Exercise 10b Functional Interchange Assemblies II ...... 10-29 Exercise 10c Optional - Flexible Component .................. 10-37 Exercise 10d Simplify components.................................. 10-41 Chapter 11 Automation.............................................................. 11-1 11.1. Assembly Relations .................................................... 11-3 General Steps.......................................................... 11-4 Start the creation of the relation ........................ 11-4 Specify the geometry to be referenced ............. 11-5 Enter a comment statement .............................. 11-5 Determine dimension symbols, as necessary ... 11-6 Enter the relation ............................................... 11-6 Symbols ....................................................... 11-7 Operators ..................................................... 11-7 Functions ..................................................... 11-8 Parameters .................................................. 11-8 Complete the relation ........................................ 11-9 Regenerate the model....................................... 11-9 Flex the model................................................... 11-9. 11.2. Assembly Pro/PROGRAM ........................................ 11-10 General Steps........................................................ 11-12. Pro/ENGINEER: Advanced Assembly Design and Management. vii.

(12) ASCENT - Center for Technical Knowledge™. Access the design program............................. 11-12 Add input statements ...................................... 11-13 Add relations ................................................... 11-14 Edit the body of the program, as necessary.... 11-14 Conditional Statements.............................. 11-14 Execute Statements................................... 11-15 Interchanging Components........................ 11-16 Fix errors, if necessary.................................... 11-17 Incorporate the design .................................... 11-18 Regenerate the model..................................... 11-18 Creating Instances..................................... 11-18 Process Flowchart ..................................... 11-19 Exercise 11a Relations I.................................................... 11-21 Exercise 11b Relations ll................................................... 11-25 Exercise 11c Program l ..................................................... 11-31 Exercise 11d Program ll .................................................... 11-37 Chapter 12 Shrinkwrap Features .............................................. 12-1 12.1. Shrinkwrap Features .................................................. 12-3 General Steps.......................................................... 12-5 Start or open an assembly ................................ 12-5 Start the creation of the shrinkwrap .................. 12-6 Define the shrinkwrap attributes........................ 12-6 Define additional elements, as necessary......... 12-8 Complete the shrinkwrap feature ...................... 12-9. 12.2. External Shrinkwrap Feature ................................... 12-10. 12.3. Simplifying using Shrinkwrap Features ................. 12-11 Replace ................................................................. 12-11 Simplified Representation Substitution.................. 12-12. Exercise 12a Creating a Shrinkwrap Feature.................. 12-13 Exercise 12b Substituting a Shrinkwrap .......................... 12-19 Chapter 13 Assembly Model Performance .............................. 13-1 13.1. viii. Factors Affecting Model Performance ...................... 13-3 CPU Speed.............................................................. 13-3 RAM......................................................................... 13-3 Swap Space ............................................................ 13-3 Network Traffic ........................................................ 13-3 Dual Processors ...................................................... 13-4 Trail Files ................................................................. 13-4 Search Paths ........................................................... 13-4 Levels of Detail ........................................................ 13-4 Software change configuration ................................ 13-5. Pro/ENGINEER: Advanced Assembly Design and Management.

(13) ASCENT - Center for Technical Knowledge™. Appendix A Model Tree Usage................................................... A-1 A.1. Search Tool................................................................... A-3 Activate the Search Tool ..................................... A-3 Define the type of item and model....................... A-4 Define the rule ..................................................... A-4 Search the model ................................................ A-5 Save the search results to a layer, if necessary.. A-5 Complete the search ........................................... A-6. A.2. Model Tree Customization .......................................... A-7 Activate model tree settings ................................ A-7 Make the desired changes .................................. A-8 Tree Filters..................................................... A-8 Tree Columns ................................................ A-8 Save the settings............................................... A-10. Pro/ENGINEER: Advanced Assembly Design and Management. ix.

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(15) Chapter 1 Introduction to Assembly Pro/ENGINEER: Introduction to Solid Modeling I & II and Pro/ENGINEER: Advanced Part Design emphasize the importance of using Pro/ENGINEER as a design tool to capture all the required design information in the model. This same statement is true for assembly design. Throughout this course, you will learn new techniques to help create and manage your assembly designs. In learning these techniques, you will learn how to create flexible assembly designs and robust models.. This chapter introduces:. 9Assembly Design Philosophies 9Component Placement 9Repeating Component Placements 9Assembly Design Approach 9Assembly File Management. 1–1.

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(17) ASCENT - Center for Technical Knowledge™. 1.1 Assembly Design Philosophies Default Datum Planes. New assemblies, like new parts, should start with default datum planes. Default datum planes provide a foundation for the assembly and should not be deleted. As references, they are convenient for constraining the first component to any subsequent components and features at assembly level. Default datum planes can be created manually as the first features in the model using Pro/ENGINEER’s default template. They have a naming convention ASM_FRONT, ASM_RIGHT and ASM_TOP, as shown in Figure 1–1.. Figure 1–1 Keep in mind that default datums must be created as the first three features in the assembly. A start-assembly or template can be used to ensure that the assembly starts with the default datum planes.. Pro/ENGINEER: Advanced Assembly Design and Management. 1–3.

(18) ASCENT - Center for Technical Knowledge™. Parts and Subassemblies. Assemblies are comprised of components, which can be parts or other assemblies. Parts can either be assembled or created in the assembly. Consider using subassemblies in the top-level assembly to organize the design. Components are listed in the model tree in the order they were added to the assembly, as shown in Figure 1–2. Notice the name of the assembly is listed first in the model tree, followed by the three assembly default datum planes, coordinate system, and the parts and subassemblies currently constrained in the assembly.. Figure 1–2. Skeleton Models. A skeleton model is used to conceptualize a top-level assembly. The use of a skeleton model can help you to simulate motion in an assembly and control space requirements.. Assembly Features. The ability to create features at the top-level assembly and subassembly level is a powerful tool. Remember that the selection of sketching planes, orientation planes, and sketching references all form parent/child relationships. Parent/child relationships that are established between two components in an assembly are termed external references. External references can be desired or undesired in your assembly depending on your design intent; they are discussed later in this course.. Parts in Assembly Mode. Pro/ENGINEER enables you to create parts in the context of the assembly. As with assembly features, you must be careful about creating external references when creating a part in Assembly mode.. 1–4. Pro/ENGINEER: Advanced Assembly Design and Management.

(19) ASCENT - Center for Technical Knowledge™. Assembly Relations. Relations are user-defined mathematical equations used to capture and control design intent in parts and assemblies. The use of assembly-level relations can drive dimensions and parameters in one component and equate them to dimensions and parameters in other components.. Assembly Regeneration. In an assembly, component features are regenerated before components. Each feature is regenerated in the order that they were added or created in the assembly. It is a good idea to regenerate every time you modify your model so that it is up-to-date. To regenerate your model, click Edit > Regenerate or select the button. To regenerate assembly features or components select the button.. Pro/ENGINEER: Advanced Assembly Design and Management. 1–5.

(20) ASCENT - Center for Technical Knowledge™. 1.2 Component Placement The Component Placement dialog box, shown in Figure 1–3, is used to constrain components within an assembly. The dialog box appears every time you choose to assemble a new component or redefine the placement of an existing component. Select here to indicate how a component being assembled should be displayed.. This section lists the currently defined constraints and enables you to redefine them. Select the button to remove an existing constraint.. Select the button to add a new constraint. Select here to specify the component reference.. Select this button to flip the reference for a constraint... Select here to specify the assembly reference. The placement status for the component is listed here. This section also enables you to toggle the Allow Assumptions option.. Select the button to complete the placement.. Select the button to preview the placement.. Select the button to cancel the placement.. Figure 1–3 The choice of constraints and references used to assemble components is important. The references selected form parent/child relationships. Ensure that the relationships that are established do not limit future manipulation (i.e., deleting a component).. 1–6. Pro/ENGINEER: Advanced Assembly Design and Management.

(21) ASCENT - Center for Technical Knowledge™. Constraints and Offsets. The Constraint Type column provides a pull-down menu with the available constraints. Constraints can be added or removed at any time using the and buttons. You can further define placement of the component using the options in the Offset column. These options include the following: • • •. Consider using Mate or Align with an offset of zero instead of Mate or Align with the Coincident option in the Offset field. The offset dimension can then be modified if necessary.. Coincident (default) 0.0 Oriented. To define an offset other than Coincident, double-click in the Offset column and select an option. The 0.0 option provides a modifiable dimension while maintaining the Align or Mate requirement. The Oriented option maintains Mate and Align without having to define a specific offset. The checkmark to the right of the offset column allows individual constraints to be enabled or disabled. Clearing the checkmark temporarily disables the constraint. The placement constraint options available in Assembly mode are described in Table 1–1. Table 1–1 Option. Description. Mate. Selected planar surfaces face opposite directions and are coplanar. Align. Selected planar surfaces face the same direction and are coplanar. Selected revolved surfaces or axes are coaxial. The system changes aligned axes or revolved surfaces into an Insert constraint. Mate Angle. Selected planar surfaces face opposite directions and are offset with an angular dimension. Align Angle. Selected planar surfaces face the same direction and are offset with an angular dimension. Insert. Selected cylindrical surfaces are coaxial. Coord Sys. Selected coordinate systems are aligned at their origins with axes facing the same direction. Tangent. Selected surfaces are tangent. Surface normals face each other. Pnt on Line. A point or vertex is constrained to be in line with an edge, axis, or datum curve. Pnt on Srf. A point/vertex is constrained to be in contact with a surface. Pro/ENGINEER: Advanced Assembly Design and Management. 1–7.

(22) ASCENT - Center for Technical Knowledge™. References. Option. Description. Edge on Srf. A straight edge is constrained to be in contact with a planar surface or datum plane. Automatic (default). The system assigns an appropriate constraint type based on the references from the assembly and the component. Constraints are specified to locate components parametrically with respect to existing components and assembly features. Similar to the interdependencies between features in a part, parent/child relationships also exist in assemblies. Any reference made to other components when assembling a new component creates a parent/child relationship. Default datum planes can be used as constraint references when defining component placements. When a datum is selected as a reference, and the orientation is not acceptable, select the. 1–8. button to flip the component.. Pro/ENGINEER: Advanced Assembly Design and Management.

(23) ASCENT - Center for Technical Knowledge™. 1.3 Revision Tools As in Part mode, the following four options enable you to easily manipulate component sequence and parent/child relationships between components: • • • •. Edit Definition. Edit References. Edit Definition Edit References Reorder Insert Mode. The Edit Definition option enables you to redefine the original placement constraints of a component using the Component Placement dialog box or redefine any of the elements specified when creating features in the assembly. To edit the definition of a component or feature in assembly mode, select the item and click Edit Definition in the pop-up menu or in the Edit pull-down menu. The Edit References option enables you to change the placement constraint references for the component within the assembly or the placement constraint for an assembly feature. This option enables you to make the necessary changes without accessing the Component Placement dialog box or the feature’s dashboard. To edit references, select the item and click Edit References in the pop-up menu or in the Edit pull-down menu. The REROUTE REFS menu appears as shown in Figure 1–14.. Figure 1–4. Pro/ENGINEER: Advanced Assembly Design and Management. 1–9.

(24) ASCENT - Center for Technical Knowledge™. It is a good idea to roll back the model so you do not try to select references that are on components below it in the model tree.. Before making any selection you are first prompted if you want to roll back the model. Rolling back the model enables you to return the assembly back to the state it was in when the component or feature was added to the assembly (i.e., all features and components below it will be suppressed). If you select “No” then all the existing components and features will remain in the model. When redefining references in a model that has not been rolled back, be sure to consider parent/child relationships. The Reroute Feat option enables you to select a component to change its assembly references. The Replace Ref option enables you to replace one reference for another. This option replaces all references that are made to the original. The Replace Ref option is recommended when a reference needs to be removed from the model.. Reorder. Components and features can be reordered in an assembly. This enables you to change the order in which they appear in the model tree and the order in which they are regenerated. To reorder an item in an assembly, select it in the model tree and drag and drop it to the required location. Be sure to consider parent/child relationships when reordering items (i.e., a child cannot exist before its parent). Features and components cannot be reordered before the first items in an assembly. You can also reorder by clicking Edit > Component Operations > Reorder. Select the item to reorder and click Done. The message window indicates where you can insert the feature, as shown in Figure 1–5. To complete the reorder, click Before or After and select the item to move before or after. Feature 6 (the selected component for reorder) can be placed before or after any feature between feature number 2 and 5.. Figure 1–5. 1–10. Pro/ENGINEER: Advanced Assembly Design and Management.

(25) ASCENT - Center for Technical Knowledge™. Insert Mode. Insert mode enables you to add new features or components before existing items in the model tree. To control inserting using the model tree, ensure that Features are enabled in the Model Tree Items dialog box (. > Tree Filters). To insert a new feature or component. in the assembly, select the icon at the bottom of the model tree and drag it to the required location. The model appears as it did at this point in the creation of the assembly. All the remaining items in the assembly are suppressed. You can continue to add components or features as necessary. Once done, select and drag the icon to the end of the model. All of the suppressed items are automatically resumed. You can also insert by clicking Edit > Component Operations > Insert Mode > Activate. Select an item to insert after. All features below the selected item are suppressed. Once you have finished adding components or features you can resume the suppressed components by clicking Cancel in the Insert Mode menu.. Pro/ENGINEER: Advanced Assembly Design and Management. 1–11.

(26) ASCENT - Center for Technical Knowledge™. 1.4 Repeating Components In many cases, components are duplicated in the assembly using the same assembly constraints, with small variations in the references or offset values. Pro/ENGINEER provides an option that enables you to repeat constraints and make the necessary modifications.. General Steps. Use the following general steps to repeat the placement of an existing component: 1.. Start the Repeat operation.. 2.. Modify constraints and references. 3.. Complete the repeat operation.. Step 1: Start the Repeat operation To repeat an existing component within an assembly, select it and click Edit > Repeat. The Repeat Component dialog box appears, as shown in Figure 1–6. The constraints and references used to assemble the selected component are listed in the Variable Assembly Refs section of the dialog box.. The 10_32_STUD component was assembled using an Align and Mate constraint, as shown in the Variable Assembly Refs section. Figure 1–6. 1–12. Pro/ENGINEER: Advanced Assembly Design and Management.

(27) ASCENT - Center for Technical Knowledge™. Step 2: Modify constraints and references To select multiple constraints, press and hold the <Ctrl> key while selecting the constraints.. To reuse constraints listed in the Variable Assembly Refs section, select the constraints and select the button. The system prompts you for the new assembly reference for each constraint. Once the references are selected the instance is listed in the Place Component section of the dialog box. In Figure 1–7 four additional components are added to the assembly by repeating constraints and selecting new references from those used to place the original 10_32_STUD component.. Each additional component that is repeated must reuse the same selected constraints as the first repeated component. If you want to reuse a different combination of constraints you must confirm the existing components and click Edit > Repeat to repeat the additional component. Four additional 10_32_STUD components are repeated by selecting a new alignment reference for each instance. The Mate reference is maintained, as shown in the Place Component section. Figure 1–7. Step 3: Complete the repeat operation Once the new references have been selected, select the button to complete the repeat operation.. Pro/ENGINEER: Advanced Assembly Design and Management. 1–13.

(28) ASCENT - Center for Technical Knowledge™. 1.5 Assembly Design Approach Two methods can be used to build the top-level assembly: existing components can be brought into the assembly and constrained or new components can be created within the context of the assembly. In the bottom-up design method, parts are created first, brought into the assembly and constrained using the Component Placement dialog box. This approach limits the ability to design around other parts or reference other geometry in the assembly. The top-down approach enables you to create parts within the context of the assembly. This approach allows for the organization of complex designs by controlling interactions and dependencies between the components within the assembly. To create a new component in an assembly, click Insert> Component> Create or select the button. The Component Create dialog box appears as shown in Figure 1–8.. Figure 1–8 The Component Create dialog box lists four types of components and their sub-types. When creating parts in Assembly mode you have the advantage of seeing the geometry of existing components. This existing geometry can be used to create geometry for the new part.. 1–14. Pro/ENGINEER: Advanced Assembly Design and Management.

(29) ASCENT - Center for Technical Knowledge™. 1.6 Assembly File Management An assembly model can contain many part files; a large amount of files require effective management. File management is important because a poorly arranged directory structure can lead to failures on retrieval. Assembly files are created in the current working directory. Components can be assembled from this directory or from another directory; however, if assembled from another directory, search paths must be established in the config.pro to ensure that the system can find the components. When you save an assembly model, the system saves the assembly model and any modified component to its original location. The following options can be used to manage an assembly file: • • •. Rename. Rename Save a Copy Backup. To rename an assembly component, click File > Rename. The Rename dialog box appears as shown in Figure 1–9.. Figure 1–9 Select the button to select the component to be renamed. Enter the new name in the New Name section of the dialog box and select the. button.. Pro/ENGINEER: Advanced Assembly Design and Management. 1–15.

(30) ASCENT - Center for Technical Knowledge™. Save a Copy. You can copy an existing file to a new name while retaining the original file. This enables you to explore different design options. To save a copy of an existing assembly, click File > Save a Copy in the menu bar. The Save a Copy dialog box appears as shown in Figure 1–10.. The copied file is by default stored in the current working directory. You can select a different directory to save the file using the Look in pull-down menu.. Figure 1–10 Enter a new name for the file and select the button to save it to the hard disk drive. The original file remains in the active window; to work on the new file you must explicitly open it. If you do not want to save changes in the original file, make sure to erase the file from session without saving.. 1–16. Pro/ENGINEER: Advanced Assembly Design and Management.

(31) ASCENT - Center for Technical Knowledge™. Backup. To avoid the loss of work, you may want to create a backup copy of your file by clicking File > Backup in the menu bar. This enables you to create a copy of the assembly and all its components in one location. The Backup dialog box appears as shown in Figure 1–11.. The button at the top of the Backup dialog box enables you to create a new directory for backup. Select this pull-down menu to navigate to the directory where you to back up the file.. Figure 1–11 The original model remains in the active window when you save the backup copy.. Browse to the target directory. The assembly and all associated part and subassembly files are stored in the target directory using the same file names as the original files. Any changes saved to the backup file remain independent of the original file.. Pro/ENGINEER: Advanced Assembly Design and Management. 1–17.

(32) ASCENT - Center for Technical Knowledge™. 1–18. Pro/ENGINEER: Advanced Assembly Design and Management.

(33) ASCENT - Center for Technical Knowledge™. Exercise 1a Goal. Assembly Constraints I In this exercise, you will assemble a turbine rotor using the required placement constrains such that the completed assembly appears as shown in Figure 1–12.. Figure 1–12 After you complete this exercise, you will be able to:. 9 Assemble generic and instances using placement constraints Task 1: Create a new assembly called rotor. 1.. Set the current working directory to the Compressor directory.. 2.. Create a new assembly called [rotor] using the default template.. Pro/ENGINEER: Advanced Assembly Design and Management. 1–19.

(34) ASCENT - Center for Technical Knowledge™. Task 2: Assemble the impeller component. You can also click Insert > Component > Assemble to assemble a component.. 1.. Select the button to assemble the first component and select impeller.prt. The model appears as shown in Figure 1–13.. Figure 1–13 2.. Align the datum planes in the component and the assembly. To unblank datum planes, select the and click Layer Tree. Select impeller.prt from the pull-down menu. Select the two datum plane layers and click Unblank in the pop-up menu.. 3.. Align datum plane TOP from the impeller model with ASM_TOP in the assembly. Align datum plane RIGHT and ASM_RIGHT and FRONT and ASM_FRONT.. 4.. Select the impeller.. 5.. Blank the datum planes in the impeller component and return to the assembly model tree.. button to complete the assembly of the. Task 3: Assemble the bolt_tie component. 1.. 1–20. Select the. button and select bolt_tie.prt.. Pro/ENGINEER: Advanced Assembly Design and Management.

(35) ASCENT - Center for Technical Knowledge™. 2.. Mate the surfaces shown in Figure 1–14.. Mate these surfaces. Figure 1–14 3.. Using the Insert constraint, select the surfaces shown in Figure 1–15.. Insert these cylindrical surfaces. Figure 1–15 Pro/ENGINEER: Advanced Assembly Design and Management. 1–21.

(36) ASCENT - Center for Technical Knowledge™. 4.. Clear the Allow Assumption option and add an Align constraint that orients datum plane RIGHT in the bolt_tie component with datum plane ASM_RIGHT in the assembly, as shown in Figure 1–16. Orient the datum planes so that this surface is aligned with ASM_RIGHT. Figure 1–16 5.. Select the bolt_tie.. button to complete the assembly of the. Task 4: Assemble an instance of the second_third_stage component. 1.. 1–22. Turn on the display of datum coordinate systems if they are not already displayed.. Pro/ENGINEER: Advanced Assembly Design and Management.

(37) ASCENT - Center for Technical Knowledge™. 2.. Select the button and select second_third_stage.prt. The Select Instance dialog box appears as shown in Figure 1–17.. Sixth.prt is a family table instance of second_third_stage.prt.. Figure 1–17 3.. Select SIXTH and select the button. The model appears in the assembly as shown in Figure 1–18.. Figure 1–18. Pro/ENGINEER: Advanced Assembly Design and Management. 1–23.

(38) ASCENT - Center for Technical Knowledge™. 4.. Constrain the PRT_DEF_CSYS coordinate system in the sixth model and the SIXTH coordinate system in the impeller part. The assembly appears as shown in Figure 1–19.. Figure 1–19 5.. Select the instance.. button to complete the assembly of the SIXTH. Task 5: Assemble an instance of the second_third_stage component.. To unblank datum planes, select the and click Layer Tree. Select impeller.prt from the pull-down menu. Select the axis layer and click Unblank from the pop-up menu.. 1–24. 1.. Select the button and assemble the FIFTH instance of the second_third_stage.prt.. 2.. Align axes A-2 in the FIFTH instance and A-2 in the SIXTH instance.. Pro/ENGINEER: Advanced Assembly Design and Management.

(39) ASCENT - Center for Technical Knowledge™. 3.. Mate the surfaces shown in Figure 1–19.. Mate these surfaces. Figure 1–20 4.. Select the instance.. button to complete the assembly of the FIFTH. Task 6: Assemble an instance of the second_third_stage component.. 1.. Select the button and assemble the FOURTH instance of the second_third_stage.prt. 2.. Align axes A-2 in the FOURTH instance and A-2 in the FIFTH instance.. Pro/ENGINEER: Advanced Assembly Design and Management. 1–25.

(40) ASCENT - Center for Technical Knowledge™. 3.. Mate the surfaces shown in Figure 1–21. Mate these surfaces. Figure 1–21 4.. Select the button to complete the assembly of the FOURTH instance.. Task 7: Assemble the generic of the second_third_stage component.. 1.. Select the button and assemble the Generic of the second_third_stage.prt.. 2.. Assemble the component using the Align and Mate constraints and similar references used when the previous instances were assembled.. 3.. Select the generic.. button to complete the assembly of the. Task 8: Assemble the first_stage component.. 1–26. 1.. Select the. button and assemble the first_stage.prt.. 2.. Assemble the component using the Insert and Mate constraints and similar references used when the previous instances were assembled.. Pro/ENGINEER: Advanced Assembly Design and Management.

(41) ASCENT - Center for Technical Knowledge™. 3.. Select the button to complete the assembly of the first_stage.prt. The assembly appears as shown in Figure 1–22.. Figure 1–22 Task 9: Assemble the coupling_adaptor.prt component.. Use Pick From List to select the hidden references.. 1.. Select the. button and assemble the coupling_adaptor.prt.. 2.. Mate the surfaces shown in Figure 1–23. Mate this surface of the bolt_tie. with this surface of the coupling_adaptor. Figure 1–23. Pro/ENGINEER: Advanced Assembly Design and Management. 1–27.

(42) ASCENT - Center for Technical Knowledge™. 3.. Insert the surfaces shown in Figure 1–24.. Mate this surface of the coupling_adaptor. with this surface of the impeller Figure 1–24. 4.. Orient the surfaces shown in Figure 1–25.. Use Mate as the constraint and Orient as the offset.. Orient this surface of the tie_bolt.... ...with this surface of the coupling_adaptor Figure 1–25. 1–28. Pro/ENGINEER: Advanced Assembly Design and Management.

(43) ASCENT - Center for Technical Knowledge™. 5.. Select the button to complete the assembly. The assembly appears as shown in Figure 1–26. Figure 1–26 6.. Save the assembly and close the window.. Pro/ENGINEER: Advanced Assembly Design and Management. 1–29.


(45) ASCENT - Center for Technical Knowledge™. Exercise 1b Goal. Assembly Constraints II In this exercise, you will assemble four components into an engine assembly using the required placement constraints. The completed assembly appears as shown in Figure 1–27.. Figure 1–27 After you complete this exercise, you will be able to:. 9 Assemble components using placement constraints. Pro/ENGINEER: Advanced Assembly Design and Management. 1–31.

(46) ASCENT - Center for Technical Knowledge™. Task 1: Create a new design assembly. 1.. Set your working directory to Engine.. 2.. Create a new assembly called [engine]. Clear the default template. Select the button. The New File Options dialog box appears as shown in Figure 1–28.. Alternatively, you can click Edit > Setup > Units and set your unit system once you have created the assembly using the default template.. Figure 1–28 3.. Select mmns_asm_design in the template section of the dialog box to set the units for the assembly. Select the. 1–32. button.. Pro/ENGINEER: Advanced Assembly Design and Management.

(47) ASCENT - Center for Technical Knowledge™. Task 2: Assemble the block_left component. To clear the model notes from the display, click Tools > Environment and clear the 3D Notes option.. 1.. Select the. button and assemble block_left.prt.. 2.. Align the bottom planar surface in the block_left model with ASM_TOP in the assembly.. 3.. Mate datum plane RIGHT in the block_left model and ASM_RIGHT in the assembly.. 4.. Align datum plane FRONT in the block_left model and ASM_FRONT in the assembly.. 5.. Select the button to complete the assembly of the block_left part. The assembly appears as shown in Figure 1–29.. Figure 1–29 Task 3: Assemble the bushing component.. 1.. Select the. button and assemble bushing.prt.. 2.. Insert the surfaces shown in Figure 1–30.. Pro/ENGINEER: Advanced Assembly Design and Management. 1–33.

(48) ASCENT - Center for Technical Knowledge™. Insert these surfaces Figure 1–30 3.. Mate the surfaces shown in Figure 1–31.. Mate these surfaces Figure 1–31 4.. Select the bushing part.. button to complete the assembly of the. 5.. Assemble bushing.prt to the other side of block_left.prt.. Task 4: Assemble the crank component.. 1–34. 1.. Select the. button and assemble crank.prt.. 2.. Insert the surfaces shown in Figure 1–30.. Pro/ENGINEER: Advanced Assembly Design and Management.

(49) ASCENT - Center for Technical Knowledge™. Insert these surfaces Figure 1–32 3.. Align datum plane DTM12 on the crank with datum plane RIGHT on the engine.. 4.. Select the button to complete the assembly of the crank part. The assembly appears as shown in Figure 1–33.. Figure 1–33 5.. Save the assembly and close the window.. Pro/ENGINEER: Advanced Assembly Design and Management. 1–35.


(51) Chapter 2 Skeleton Models Skeleton techniques are used in Pro/ENGINEER Assembly mode to create an underlying structure for assembly models. It generally consists of datum and surface features to which assembly components are constrained and geometry can be created.. This chapter introduces:. 9Skeleton Models to control Parent/Child Relationships 9Skeleton Models for Simulating Motion 9Skeleton Models for Spatial Claims 9Skeleton Models for Geometry Creation. 2–1.

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(53) ASCENT - Center for Technical Knowledge™. 2.1 Skeleton Models A skeleton model acts as a three-dimensional layout of an assembly and facilitates a top-down design strategy. The skeletal structure is defined by creating part-level datum, surface, and solid features in the skeleton model. A skeleton model can be used to control parent/child relationships, incorporate motion, define spatial claims and create geometry. By default, only a single skeleton can exist in an assembly. Subassemblies can also contain a skeleton; however, it must be created in the subassembly.. Parent/Child Relationships. By assembling to a skeleton instead of referencing other components, the likelihood of creating unwanted parent/child relationships between components is reduced. Using this technique makes operations such as suppressing, deleting, and interchanging components easier, since fewer dependency relationships exist between components. The component shown in Figure 2–1 is being assembled to datum features in a skeleton model. Additional components are assembled referencing only the skeleton so that no parent/child relationships are established between components.. Consider suppressing components as you are selecting your assembly references to ensure that references are only established with the skeleton model.. Align axis A_7 and axis CONNECTING_ROD1.. Align axis A_5 and axis CRANK.. Align datum plane BLJ to the end surface.. Figure 2–1. Pro/ENGINEER: Advanced Assembly Design and Management. 2–3.

(54) ASCENT - Center for Technical Knowledge™. Incorporating Motion. When creating the skeleton, the capacity for motion can be incorporated into the design using dimensioning and construction techniques. You can simulate motion by modifying the skeleton model dimensions in the assembly instead of modifying the components or the assembly constraints. The assembly shown in Figure 2–2 is created by assembling components to the features in the skeleton model. Changes made to the angular dimension value affect the position of components in the top-level assembly. This is because the linear entity in the skeleton was used as a reference when assembling the components. The angular dimension in the skeleton can be modified.. The linear curve in the skeleton was dimensioned using an angular value.. The new dimension value affects the component’s positions in the assembly, simulating rotational motion.. The components in the assembly were assembled referencing the skeleton curves.. Figure 2–2. 2–4. Pro/ENGINEER: Advanced Assembly Design and Management.

(55) ASCENT - Center for Technical Knowledge™. Spatial Claims. A skeleton can be used to create conceptual parts that define regions of an assembly, known as "spatial claims". These regions represent the volume to be occupied or avoided by components that have yet to be created. The skeleton model representing the volume of these regions can then be referenced during the construction of these components to ensure they fall within location and volume limitations. For example, the skeleton model shown at the top of Figure 2–3 is a skeleton model that represents the base and the electrical components for a power assembly. Both of these sub-assemblies have not been designed yet; however, their size is accounted for when the top-level assembly is created, as shown a the bottom of Figure 2–3. This surface feature is created in the skeleton to represent the electrical subassembly.. This surface feature is created in the skeleton to represent the base subassembly.. Figure 2–3. Pro/ENGINEER: Advanced Assembly Design and Management. 2–5.

(56) ASCENT - Center for Technical Knowledge™. Geometry Creation. In a top-down design environment, component geometry can be created in the context of the assembly. The benefit of this technique is that references can be made between components to create the required geometry. However, as the number of references increase they can become difficult to organize and control. In this case, creating or copying cross-referenced geometry from the skeleton model creates a centralized location for exchanging information between assembly components. The reference geometry is easily distinguished from the final assembly geometry because it is located in a single location. The solid model shown on the right-hand side of Figure 2–4 is created in the assembly, referencing datum points PNT0 and PNT1 from the skeleton model, as shown in the sketched section on the left-hand side. Additional components can be created in the assembly referencing the same skeleton.. Figure 2–4. 2–6. Pro/ENGINEER: Advanced Assembly Design and Management.

(57) ASCENT - Center for Technical Knowledge™. General Steps. Use the following general steps to create skeleton models: 1.. Create a skeleton model.. 2.. Define the skeleton geometry.. Step 1: Create a skeleton model To create a skeleton model, click Insert > Component > Create or by selecting the button in the toolbar. Select the Skeleton Model option in the Component Create dialog box, enter a name for the skeleton, and select the button. The Creation Options dialog box appears as shown in Figure 2–5. The default skeleton name consists of the parent assembly model name with "skel" appended to it (e.g., crank_skel.prt). You can also enter a user-defined name for the skeleton.. Figure 2–5 Skeleton models can be created using one of the following three options: • • •. Copy From Existing Empty Create First Feature. The Copy From Existing option copies features from an existing model. This option is valuable when the skeleton model is created prior to the top-level assembly.. Pro/ENGINEER: Advanced Assembly Design and Management. 2–7.

(58) ASCENT - Center for Technical Knowledge™. The Empty option creates a blank part file where all features, including the default datum planes, must be created. The Create First Feature option creates a feature in the skeleton model at the assembly level. This option can be used to create the default datum planes for the skeleton model by selecting three perpendicular planes in the assembly to copy into the skeleton. The skeleton model always exists as the first component in the assembly model tree. Even if it is created after other components, the skeleton is placed before the assembly default datum planes and any previously assembled components. If there are existing components, an origin to origin constraint is added to align the origin (the point of intersection of the three default datum planes) of the first component to the origin of the skeleton model. This alignment may result in the reorientation of the first component and its children. You can manually redefine the component’s placement constraints to correct the orientation. You can avoid this situation entirely by creating the skeleton model before any components are assembled. Skeleton models appear with a unique icon in the model tree to distinguish them from other components. Figure 2–6 shows the model tree icons for parts, sub-assemblies and skeletons.. Part Component Icon. Assembly Component Icon. Skeleton Component Icon. Figure 2–6. Step 2: Define the skeleton geometry To define the geometry for a skeleton created within the assembly, use either of the following techniques: • •. Activate the skeleton and create the geometry within the context of the assembly Open the skeleton in Part mode and create the geometry. Any type of feature can be added to the skeleton model, including solid and sheet metal features; however, skeleton models typically only consist of surface and datum features.. 2–8. Pro/ENGINEER: Advanced Assembly Design and Management.

(59) ASCENT - Center for Technical Knowledge™. 2.2 Skeleton Properties Skeleton models in Pro/ENGINEER have the following properties: •. • •. •. • • • • •. By default, only one skeleton model can be created for an assembly. By setting the configuration option multiple_skeletons_allowed to "yes", you can have more than one skeleton belonging to an assembly. Skeleton models can exist in sub-assemblies but must be created at the subassembly level. Skeleton models are always given the default name of assembly_name_skel.prt where assembly_name is the name of the parent assembly model. You can use an alternative name if desired. If you are creating multiple skeletons, the default name is incremented for each skeleton (assembly _name _ skel0002.prt). Skeleton models can be created at any time but are automatically reordered to appear before the first component and feature in the assembly. Assembly features such as cuts and holes do not intersect skeleton models. Skeleton models are not included in the mass property calculations. Skeleton models can be filtered out of assembly bill of material listings. The display of skeleton models can be removed from assembly drawings and simplified representations. By default, the color of all solid and surface geometry in the skeleton is medium blue (R=0, G=0, B=49). This color is controlled by the configuration option skeleton_model_default_color. The color is defined by three values (ranging between 0 and 100), specifying the percentages of red, green and blue. This option only applies to skeleton models created after the configuration option is set.. Pro/ENGINEER: Advanced Assembly Design and Management. 2–9.


(61) ASCENT - Center for Technical Knowledge™. Exercise 2a Goal. Creating a Skeleton part After you complete this exercise, you will be able to:. 9 Create a skeleton model that defines motion in an assembly In this exercise, you create the assembly shown in Figure 2–7 and Figure 2–8 using a skeleton model. The skeleton model is used to define circular motion for the crankshaft and linear motion for the pistons.. Figure 2–7 2 4. 1. 4. 5. 3 6. 2 3. Figure 2–8. Pro/ENGINEER: Advanced Assembly Design and Management. 2–11.

(62) ASCENT - Center for Technical Knowledge™. The assembly components include the following: • • • • • •. bearing_journal_short.prt piston.asm piston_pin.prt connecting_rod.prt connecting_rod_journal.prt bearing_journal_main.prt. Task 1: Create the assembly and set up the skeleton model. 1.. Change your working directory to the Piston directory.. 2.. Create a new assembly called [crank_piston] using the default template.. 3.. Set the length units for the assembly by clicking Edit > Set Up. Click Units in the ASSEM SETUP menu.. 4.. Click millimeter Newton Second (mmNS) in the Systems of Units section of the Units Manager dialog box. Select the button to set the new units.. 5.. Click Convert Existing Numbers (Same Size) in the Warning dialog box. Select the. 2–12. button.. 6.. Select the. button.. 7.. Click Done in the ASSEM SETUP menu.. 8.. Select the. button to create a new component.. Pro/ENGINEER: Advanced Assembly Design and Management.

(63) ASCENT - Center for Technical Knowledge™. 9.. Select Skeleton Model from the type menu of the Component create dialog box, as shown in Figure 2–9. Select the button to accept the default name of crank_piston_skel.. Figure 2–9 10. Click Empty in the Creation Options dialog box. 11. Select the. button.. 12. Save the assembly and close the window. Task 2: Add features to the Skeleton model. 1.. Open crank_piston_skel.prt in Part mode.. 2.. Ensure that the length units of the part are set to millimeters to match those of the other components in the assembly.. 3.. Select the. 4.. Create a sketched datum curve that represents the overall length. button to create default datum planes.. of the assembly. Select DTM3 datum plane, and select the button. Select the Curve dialog box.. Pro/ENGINEER: Advanced Assembly Design and Management. button from the Sketched Datum. 2–13.

(64) ASCENT - Center for Technical Knowledge™. 5.. Sketch the curve so that one endpoint of the curve is aligned to DTM1, as shown in Figure 2–10.. The endpoint of the line should be aligned to DTM1.. Figure 2–10 6.. 2–14. The first component in the assembly, bearing_journal_main.prt, is aligned to DTM1 of the skeleton. Rename DTM1 to reflect this alignment. Double-click on DTM1 in the model tree and rename the datum plane to [BJL].. Pro/ENGINEER: Advanced Assembly Design and Management.

(65) ASCENT - Center for Technical Knowledge™. 7.. Create a datum plane offset from datum plane BJL. Use an offset dimension of [-107]. This locates the first instances of the piston, piston_pin, and connecting_rod components. See Figure 2–11.. 8.. Rename this datum plane to [PCR1].. Figure 2–11 9.. Sketch a datum curve on datum plane PCR1 that controls the motion of the first piston. Use PCR1 as the sketching plane and DTM2 as the top reference. Use DTM3 and DTM2 as sketching references.. Pro/ENGINEER: Advanced Assembly Design and Management. 2–15.

(66) ASCENT - Center for Technical Knowledge™. 10. Sketch the two line entities first and dimension them as shown in Figure 2–12. Create the circle to represent the path of the rotation.. Sketch the two linear entities first and then sketch the circle. The diameter of the circle should be driven by the length of the shorter line.. Figure 2–12 A dimension symbol can be changed from the default (e.g., d12) to help identify the dimension when it is modified and used in relations.. 2–16. 11. When the feature is completed, change the symbol of the angular dimension. Select the datum curve and click Edit in the pop-up menu. 12. Select the angular dimension and click Properties in the pop-up menu. From the Dimension Text tab, change the name of the dimension to [crank_angle] using the Name field. The sketch appears as shown in Figure 2–13.. Pro/ENGINEER: Advanced Assembly Design and Management.

(67) ASCENT - Center for Technical Knowledge™. Figure 2–13 13. Select the button to create two datum points. Create the datum points through the vertices of the datum curve shown in Figure 2–14. Select these two vertices to create the datum points.. Figure 2–14 Press the <Ctrl> key while selecting the references to select multiple references for the axis.. 14. Select the button to create a datum axis. Create the datum axes normal to datum plane PCR1 and through one of the datum points just created. Create a second datum axis normal to datum plane PCR1 and through the other datum point created in the previous step.. Pro/ENGINEER: Advanced Assembly Design and Management. 2–17.

(68) ASCENT - Center for Technical Knowledge™. 15. Rename the axes using the names shown in Figure 2–15. These axes are used as assembly references.. Figure 2–15 16. Create a datum plane offset from datum plane BJL by a distance of [-117]. Rename this new datum plane to [CRJ]. This plane is used to locate the connecting rod journal component. The sketch appears as shown in Figure 2–16 (axes display has been disabled for clarity).. Figure 2–16 17. Create a datum plane offset from datum plane BJL. Use an offset dimension of [-127]. This locates the second instances of the piston, piston_pin, and connecting_rod components. Rename this datum plane [PCR2]. 18. Create a datum plane offset from datum plane BJL. Use an offset dimension of [-163]. This locates the bearing_journal_short. Rename this datum plane [BJS].. 2–18. Pro/ENGINEER: Advanced Assembly Design and Management.

(69) ASCENT - Center for Technical Knowledge™. 19. Sketch a datum curve on datum plane PCR2 that controls the motion of the second piston. Use PCR2 as the sketching plane and DTM2 as the top reference. Select the four sketching references shown in Figure 2–17. Sketch the two lines segments and the circle.. Select these four sketching references: 1. Point PNT1 2. Top half of circle 3. Bottom half of circle 4. DTM3. Sketch these entities: 1. Circle 2. Line 3. Line. Figure 2–17. Pro/ENGINEER: Advanced Assembly Design and Management. 2–19.

(70) ASCENT - Center for Technical Knowledge™. The completed feature appears as shown in Figure 2–18.. Figure 2–18 20. Create two datum points through the vertices of the datum curve shown in Figure 2–19.. Select these two vertices to create the datum points.. Figure 2–19. 2–20. Pro/ENGINEER: Advanced Assembly Design and Management.

(71) ASCENT - Center for Technical Knowledge™. 21. Create two datum axes. Make them normal to datum plane PCR2 and through the datum points just created. Rename the axes using the names shown in Figure 2–20.. Figure 2–20 22. Create an axis at the intersection of datum planes DTM2 and DTM3. Rename the axis to [CRANK], as shown in Figure 2–21.. Figure 2–21 23. The skeleton model is now complete. Save the part and close the window.. Pro/ENGINEER: Advanced Assembly Design and Management. 2–21.

(72) ASCENT - Center for Technical Knowledge™. Task 3: Assemble the components to the skeleton. 1.. Open crank_piston.asm. You should see the geometry of the skeleton model.. 2.. Assemble the component bearing_journal_main.prt, as shown in Figure 2–22 and Figure 2–23. Keep the Automatic constraint default option and select entities to align. The Align constraint is assigned automatically.. Align axis A_7 and axis CONNECTING_ROD1.. Align axis A_5 and axis CRANK.. Align datum plane BLJ to the end surface.. Figure 2–22. Figure 2–23. 2–22. Pro/ENGINEER: Advanced Assembly Design and Management.

(73) ASCENT - Center for Technical Knowledge™. 3.. Assemble the component connecting_rod.prt as shown in Figure 2–24 and Figure 2–25.. Align axis A_3 to axis PISTON1.. Align axis A_5 to axis CONNECTING_ROD1.. Align DTM1 to PCR1.. Figure 2–24. Figure 2–25. Pro/ENGINEER: Advanced Assembly Design and Management. 2–23.

(74) ASCENT - Center for Technical Knowledge™. 4.. Assemble the component piston_pin.prt, as shown in Figure 2–26 and Figure 2–27.. Align axis A_3 and axis PISTON1.. Align DTM3 and PCR1.. Figure 2–26. Figure 2–27. 2–24. Pro/ENGINEER: Advanced Assembly Design and Management.

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