Automated design of sheet metal punches for bending multiple parts in a single setup
Sheet metal bending is a process in which bends are formed using a combination of a punch and a die. A very large number of mechanical products such as furniture panels, shelves, cabinets, housing for electro-mechanical devices, etc. are created by using the sheet metal bending process. Bending tools need to satisfy the following two criteria: (1) tools should be able to withstand bending forces, and (2) tool shapes should be such that there is no tool-part interference. In this paper, we describe a methodology for automatically designing shapes of bending punches for bending multiple parts in a single setup. We create parametric geometric models of punches. These parametric models describe the family of possible punch shapes. Using the part geometry and parametric punch shape models, we automatically generated constraints on tool parameters that eliminate the possibility of part-tool interference. We use mixed-integer techniques to identify parameters of punch shapes that result in the maximum punch strength. Finally, we perform strength analysis of the designed punch shape using "nite element analysis methods, to verify that the designed punch shape is capable of withstanding the bending forces. 2001 Elsevier Science Ltd. All rights reserved.
Feature reasoning for sheet metal components
The objective of this paper is to develop a set of principles for extracting, recognizing and reasoning about features from sheet metal parts which are created in the CAD system. Recognition of such features will enable the automatic evaluation of designs and the development of process plans by among other things, mapping form features to tools needed to produce the form. The principles are developed by studying the face-oriented representations of features and deriving concepts which relate the features geometrically and topologically. Subsequently, the processes that relate to the geometrical forms are used to further uniquely identify the features.
Composite monolayer fabrication by an arc-spray process
A single layer (monotape) technique for fabricating complex high-temperature tungsten-fiber-reinforced superalloy composites is proposed. The fabrication of sheets of arc-sprayed monotape 38 cm wide and 122 cm long has been demonstrated. Composites fabricated using the method are shown to have equal tensile strength and a cleaner matrix than composites fabricated from powder metal cloth monotapes, and the present technique is less expensive than the powder metal fabrication techniques.