1、中文 5496 字 附录 翻译部分 英文原文 Introduction to Computer Integrated Manufacturing D .L.Goetsch CIM Defined Computer integrated manufacturing (CIM) is the term used to describe the modem approach to manufacturing. Although CIM encompasses many of the other advanced manufacturing technologies such as CNC； CAD/
2、CAM, robotics, and just-in-time (JIT) deliuery, it is more th a new tech. noloml or. a cncept. puter integrated :manufacturing is an entirely new approach to manufacturing, a new way of doing business. To understand CIM, it is necessary to begin with a comparison of modern and traditional manufactur
3、ing. Modem manufacturing encompasses all of the activities and processes necessary to convert raw materials into finished products, deliver them to the market ,and support them in the field . These activities include the following: 1) Identifying a need for a product. 2) Designing a product to meet
4、the needs. 3) Obtaining the raw materials needed to produce the product. 4) Applying appropriate processes to transform the raw materials into finished products, 5) Transporting products to the market. 6) Maintaining the product to ensure proper performance in the field. This broad, modern view of m
5、anufacturing can be compared with the more limited traditional view that focused almost entirely on the conversion processes. The old approach excluded such critical preconversion elements as market analysis reseach, development, and design, as well as such after-conversion elements as product deliv
6、ery and product maintenance. In other words, in the old approach to manufacturing, only those processes that took place on the shop floor were considered manufacturing. This traditional approach of separating the overall concept into numerous stand-alone specialized elements was not fundamentally ch
7、anged with the advent of automation. With CIM, not only are the various elements automated, but the islands of automation are all linked together or integrated. Integration means that a system can provide complete and instantaneous sharing of information. In modern manufacturing, integration is acco
8、mplished by computers. CIM, then, is the total integration of all components involved in converting raw materials into finished products and getting the products to the market. Historical Development of CIM The term computer integrated manufacturing was developed in I974 by Joseph Harrington as the
9、title of a book he wrote about tying islands of automation together through the use of computers. It has taken many years for CIM to develop as a concept, but integrated manufacturing is not really new. In fact, integration is where manufacturing actually began. Manufacturing has evolved through fou
10、r distict stages: Manual manufacturing. Mechanization / Specialization Automation. Integration. Manual Manufacturing Manual manufacturing using simple hand tools was actually integrated manufacturing. All information needed to design, produce, and deliver a product was readily available because it r
11、esided in the mind of the one person who performed all of the necessary tasks, The tool of integration in the earliest years of,manufacturing was the human mind of the craftsman who designed, produced, and delivered the product, An example of integrated manual manufacturing is the village blacksmith
12、 producing a special tool for a local farmer. The blacksmith would have in his mind all of the information needed to design, produce, and deliver the farmers tools. In this example, all elements of manufacturing are integrated. Mechanization / Specialization With the advent of the industrial revolut
13、ion, manufacturing processes became both specialized and mechanized. Instead of one person designing, producing, and delivering a product, workers and / or machines performed specialized tasks within each of these broad areas. Commtmication among these separate entities was achieved using drawings,
14、specifications, job orders, process plans, and a variety of other communication aids. To ensure that the finished product matched the planned product, the concept of uality control was introduced The positive side of the mechanization /specialization stage was that it permitted mass production, inte
15、rchange, ability of parts, different levels of accuracy, and uniformity. The disadvantage is that the lack of integration led to a great deal of waste. Automation Automation improved the performance and enhanced the capabilities of both people and machines within specialized manufacturing components
16、. For example, CAD enhanced the capability of designers and drafters. CNC enhanced the capabilities of machinists and computer-assisted planners. But the improvements brought on by automation were isolated within individual components or islands. Because of this, automation did not always live up to
17、 its potential. To understandthe limitations of automation with regard to overall productivity impro- vement, consider the following analogy. Suppose that various subsystems of an automobile (i. e., the engine, steering, brakes) were automated to make the drivers job easier. Automatic acceleration,
18、deceleration, steering, and braking would certainly be more efficient than the manual versions. However, consider what would happen if these various automated subsystems were not tied together in a way that allowed them to communicate and share accurate up-to-date information instantly and continual
19、ly. One system might be attempting to accelerate the automobile while another system was attempting to apply the brakes. The same limitations apply in an automated manufacturing setting. These limitations are what led to the current stage in the development of manufacturing, integration. Integration.
