参数控制型腔布局系统注射注塑模具类外文文献翻译中英文翻译外文翻译.docx

1、参数控制型腔布局系统注射注塑模具类外文文献翻译中英文翻译外文翻译Int J Adv Manuf Technol (2003) 21:807819Ownership and Copyright 2003 Springer-Verlag London LimitedA Parametric-Controlled Cavity Layout Design System for aPlastic Injection MouldM. L. H. Low and K. S. LeeDepartment of Mechanical Engineering, National University of Si

2、ngapore, SingaporeToday, the time-to-market for plastic products is becoming shorter, thus the lead time available for making the injection mould is decreasing. There is potential for timesaving in the mould design stage because a design process that is repeatable for every mould design can be stand

3、ardised. This paper presents a methodology for designing the cavity layout for plastic injection moulds by controlling the geometrical para- meters using a standardisation template. The standardisation template for the cavity layout design consists of the configur- ations for the possible layouts. E

4、ach configuration of the layout design has its own layout design table of all the geometrical parameters. This standardisation template is pre-defined at the layout design level of the mould assembly design. This ensures that the required configuration can be loaded into the mould assembly design ve

5、ry quickly, without the need to redesign the layout. This makes it useful in technical discussions between the product designers and mould designers prior to the manu- facture of the mould. Changes can be made to the 3D cavity layout design immediately during the discussions, thus saving time and av

6、oiding miscommunication. This standardisation tem- plate for the cavity layout design can be customised easily for each mould making company to their own standards.Keywords: Cavity layout design; Geometrical parameters; Mould assembly; Plastic injection mould design; Standardis-ation templateon it a

7、nd provides the mechanism for molten plastic transfer from the machine to the mould, clamping the mould by the application of pressure and the ejection of the formed plastic part. The injection mould is a tool for transforming the molten plastic into the final shape and dimensional details of the pl

8、astic part. Today, as the time-to-market for plastic parts is becoming shorter, it is essential to produce the injection mould in a shorter time.Much work had been done on applying computer techno- logies to injection mould design and the related field. Knowl- edge-based systems (KBS) such as IMOLD

9、1,2, IKMOULD 3, ESMOLD 4, the KBS of the National Cheng Kang University, Taiwan 5, the KBS of Drexel University 6, etc. were developed for injection mould design. Systems such as HyperQ/Plastic 7, CIMP 8, FIT 9, etc. are developed for the selection of plastic materials using a knowledge-based approa

10、ch. Techniques have also been developed for parting design in injection moulding 1012.It has been observed that although mould-making industries are using 3D CAD software for mould design, much time is wasted in going through the same design processes for every project. There is great potential for

11、timesaving at the mould design stage if the repeatable design processes can be standard- ised to avoid routine tasks. A well-organised hierarchical design tree in the mould assembly is also an important factor 13,14. However, little work has been done in controlling the para-meters in the cavity lay

12、out design; thus this area will be our main focus. Although there are many ways of designing the1. IntroductionPlastic injection moulding is a common method for the mass production of plastic parts with good tolerances. There are two main items that are required for plastic injection moulding. They

13、are the injection-moulding machine and the injection mould. The injection-moulding machine has the mould mountedCorrespondence and offprint requests to: K. S. Lee, Department of Mechanical Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 119260. E-mail address: mpelee

14、ks nus.edu.sgReceived 8 January 2002Accepted 16 April 2002cavity layout 15,16, mould designers tend to use only conven- tional designs, thus there is a need to apply standardisation at the cavity layout design level.This paper presents a methodology for designing the cavity layout for plastic inject

15、ion moulds by controlling the parameters based on a standardisation template. First, a well-organised mould assembly hierarchy design tree had to be established. Then, the classification of the cavity layout configuration had to be made to differentiate between those with standard con- figurations a

16、nd those with non-standard configurations. The standard configurations will be listed in a configuration database and each configuration has its own layout design table that controls its own geometrical parameters. This standardisation808 M. L. H. Low and K. S. LeeFig. 1. Front insert (cavity) and b

17、ack insert (core).template is pre-defined at the layout design level of the mould assembly design.2. Cavity Layout Design for a PlasticInjection MouldAn injection mould is a tool for transforming molten plastic into the final shape and dimensional details of a plastic part. Thus, a mould contains an

18、 inverse impression of the final part. Most of the moulds are built up of two halves: the front insert and the back insert. In certain mould-making industries, the front insert is also known as the cavity and the back insert is known as the core. Figure 1 shows a front insert (cavity) and a back ins

19、ert (core). Molten plastic is injected into the impression to fill it. Solidification of the molten plastic then forms the part. Figure 2 shows a simple two-plate mould assembly.Fig. 2. A simple mould assembly.2.1 Difference Between a Single-Cavity and aMulti-Cavity MouldVery often, the impression i

20、n which molten plastic is being filled is also called the cavity. The arrangement of the cavities is called the cavity layout. When a mould contains more than one cavity, it is referred to as a multi-cavity mould. Figures 3(a) and 3(b) shows a single-cavity mould and a multi-cavity mould. A single-c

21、avity mould is normally designed for fairly large parts such as plotter covers and television housings. For smaller parts such as hand phone covers and gears, it is always more economical to design a multi-cavity mould so that more parts can be produced per moulding cycle. Customers usually deter- m

22、ine the number of cavities, as they have to balance theinvestment in the tooling against the part cost.2.2 Multi-Cavity LayoutA multi-cavity mould that produces different products at the same time is known as a family mould. However, it is not usual to design a mould with different cavities, as the

23、cavities may not all be filled at the same time with molten plastic of the same temperature.On the other hand, a multi-cavity mould that produces the same product throughout the moulding cycle can have a bal- anced layout or an unbalanced layout. A balanced layout is one in which the cavities are al

24、l uniformly filled at the same time under the same melt conditions 15,16. Short moulding can occur if an unbalanced layout is being used, but this can be overcome by modifying the length and cross-section of the runners (passageways for the molten plastic flow from the sprue to the cavity). Since th

25、is is not an efficient method, it is avoided where possible. Figure 4 shows a short moulding situation due to an unbalanced layout.A balanced layout can be further classified into two categor-ies: linear and circular. A balanced linear layout can accommo- date 2, 4, 8, 16, 32 etc. cavities, i.e. it

26、follows a 2n series. A balanced circular layout can have 3, 4, 5, 6 or more cavities, but there is a limit to the number of cavities that can be accommodated in a balanced circular layout because of space constraints. Figure 5 shows the multi-cavity layouts that have been discussed.3. The Design App

27、roachThis section presents an overview of the design approach for the development of a parametric-controlled cavity layout design system for plastic injection moulds. An effective working method of mould design involves organising the various subas- semblies and components into the most appropriate

28、hierarchy design tree. Figure 6 shows the mould assembly hierarchy design tree for the first level subassembly and components. Other subassemblies and components are assembled from the second level onwards to the nth level of the mould assembly hierarchy design tree. For this system, the focus will

29、be made only on the “cavity layout design”.Fig. 3. (a) A single cavity mould. (b) A multi-cavity mould.A Cavity Layout Design System 8093.1 Standardisation ProcedureFig. 4. Short moulding in an unbalanced layout.In order to save time in the mould design process, it is necessary to identify the features of the design that are com- monly used. The design processes that are repeatable for every mould design can then be standardised. It can be seen from Fig. 7 that there are two sections that interplay in the stan- dardisation procedure for the “cavity layout design”: component assembly sta