Creation Part Family for Reuse Library
Parametric feature modeling technology is the foundation of parts reuse. Parts reuse method in NX includes: Expression, Spreadsheet, part family, User Defined Feature and NX/OPEN [2-4]. Part families provide a method to quickly define a family of similar parts using a spreadsheet based on a single template part [5]. Each family member is based on a single template part, which can be a piece part or an assembly. In the process of creation part family, Excel application will be executed. For standard parts, part family is adopted usually to create model. The following with a bolt example is given to illustrate the method and process of creating part family of standard parts. Step1: Create a new Part, named ‘Hex Bolt,AM.prt’. Step2: Enter MODELING application, choose Tool→Expression. In the Expression dialog, designer could set up important parameter of the relative model. In this case, the two parameters of LENGTH and DIAMETER should be defined first because they would be invoked in reuse library subsequent. Step3: Create the solid model of bolt. Step4: Choose Tool→Part Families. Create model family table in Excel application that invoked by NX. Step5: Finish part family creation. Create bitmap file of part family diagram, as shown in Fig. 1. Bitmap file can be made by Photoshop software etc. In this case, bitmap file is named Hex Bolt, AM.bmp.
Reuse Library Directory
Reuse library navigator structure is shown in Fig. 2 that organize reuse objects by a hierarchical tree structure. The reuse object relative files are placed to the corresponding file directory, for example, ‘…\NXPARTS\Reuse Library\Reuse Examples\Standard Parts’. In order to manage file conveniently, create new folder “Hex Bolt” under the directory of ‘Standard Parts’. Copy the Hex Bolt,AM.prt and Hex Bolt,AM.bmp two files to the new folder ‘Hex Bolt’.
Fig. 1 Part family diagram Fig. 2 Reuse library navigator structure
Manufacturing Technology, Electronics, Computer and Information Technology Applications
Creation Knowledge Components
Designer can create personal knowledge components in reuse library through creating KRX file [6]. The KRX file defines the relationship between component file and non-geometry file, for example, outer spreadsheet, image file and other information of design automation. The KRX file is also a part to define how to display the ‘Add Reusable Component’ dialog. The steps to create KRX file as follow: Step1: In reuse library main board, choose corresponding member node, for example ‘Hex Bolt’. Step2: In ‘Member Select’ panel, right click on a component, choose ‘Create KRX file’, as shown in Fig. 3. Step3: Edit "Create/Edit KRX file" dialog, as shown in Fig.4. Assign ‘Output File’; choose the main member parameter of standard parts at ‘Primary Parameters’; choose the bitmap file made earlier at the same directory. Though the above operation, a new ‘.krx’ file is gained at the corresponding reuse library file directory.
Fig. 3 Create KRX file Fig. 4 Create/Edit KRX file
Application of Standard Parts in Reuse Library
After defined knowledge components in reuse library, there are two ways to perform part family or model template. First, drag the part family or model template into graphics window directly. Second, in ‘Member Select’ panel, right click a component; choose ‘Add to Assembly’. In ‘Add Reusable Component’ dialog box, as shown in Fig.5, choose ‘Primary Parameters’ to ensure the correct ‘member part parameter’. If the part is added to assembly, then choose the parameter Placement, Pocket etc to make it get the correct position and restriction.