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Just-in-time (JIT) manufacturing, also known as just-in-time production or the Toyota production system (TPS), is a methodology aimed primarily at reducing flow times within production as well as response times from suppliers and to customers. Following its origin and development in Japan, largely in the 1960s and 1970s and particularly at Toyota,〔Ohno, T. 1978. ''Toyota Production System—Beyond Management of Large-Scale Production''. Tokyo: Diamond Publishing (in Japanese).〕〔Shingo, Shigeo. 1985. ''A Revolution in Manufacturing: The SMED System''. Stamford, Ct.: Productivity Press.〕 JIT migrated to Western industry in the 1980s, where its features were put into effect in many manufacturing companies—as is attested to in several books〔Hall, Robert W. 1983. ''Zero Inventories''. Homewood, Ill., Dow Jones-Irwin.〕〔Goddard, Walter E. 1986. ''Just-in-Time: Surviving by Breaking Tradition''. Essex Junction, Vt." Oliver Wight Ltd.〕〔Suzaki, Kyoshi. 1987. ''The New Manufacturing Challenge: Techniques for Continuous Improvement''. New York: Free Press〕〔Hall, Robert W. 1987. ''Attaining Manufacturing Excellence: Just-in-Time, Total Quality, Total People Involvement''. Homewood, Ill.: Dow Jones-Irwin.〕〔Hay, Edward J. 1988. ''The Just-in-Time Breakthrough: Implementing the New Manufacturing Basics''. New York: Wiley.〕 and compendia of case studies and articles from the 1980s.〔Sepehri, Mehran. 1986. ''Just-in-Time: Not Just in Japan: Case Studies of American Pioneers in JIT Implementation''. Falls Church, Va.: American Production and Inventory Control Society〕〔Mortimer, J. 1986. ''Just-in-Time: An Executive Briefing''. Kempston, Bedford, UK: IFS Ltd.〕〔Voss, Chris, and David Clutterbuck. 1989. ''Just-in-Time: A Global Status Report''. UK: IFS Publications.〕〔Jasinowski, Jerry, and Robert Hamrin. 1995. ''Making It in America: Proven Paths to Success from 50 Top Companies''. New York: Simon & Schuster.〕 Alternative terms for JIT manufacturing have been used. Motorola's choice was short-cycle manufacturing (SCM).〔Heard, Ed. 1987. Short cycle manufacturing: the route to JIT. ''Target''. 2 (3) (fall) 22–24.〕〔High, W. 1987. Short cycle manufacturing (SCM) implementation: an approach taken at Motorola. ''Target'', 3 (4) (Winter), 19–24.〕 IBM's was continuous-flow manufacturing (CFM),〔Barkman, William E. 1989. ''In-Process Quality Control for Manufacturing''. Boca Raton, Fl.: CRC Press.〕〔Bowers, G.H., Jr. 1991. Continuous flow manufacturing. ''Proc. SPIE1496, 10th Annual Symposium on Microlithography''. (March 1, 1991), 239–246.〕 and demand-flow manufacturing (DFM), a term handed down from consultant John Constanza at his Institute of Technology in Colorado.〔Roebuck, Kevin. 2011. ''Business Process Modeling: High-impact Emerging Technology—What You Need to Know: Definitions, Adoptions, Impact, Benefits, Maturity, Vendors''. Tebbo, p 32.〕 Still another alternative was mentioned by Goddard, who said that "Toyota Production System is often mistakenly referred to as the 'Kanban System,'" and pointed out that kanban is but one element of TPS, as well as JIT production.〔Goddard, op. cit., p. 11.〕 But the wide use of the term ''JIT manufacturing'' throughout the 1980s faded fast in the 1990s, as the new term ''lean manufacturing'' became established〔Womack, James P., Jones, Daniel T., and Roos, Daniel (1991), ''The Machine That Changed the World: The Story of Lean Production'', HarperBusiness, 2003, ISBN 0-06-097417-6.〕〔Black, J.T., and S.L. Hunter. 2003. ''Lean Manufacturing Systems and Cell Design''. Dearborn, Mich.: Society of Manufacturing Engineers, 205, 307–326.〕 as "a more recent name for JIT."〔Hyer, Nancy, and Urban Wemmerlöv. 2002. ''Reorganizing the Factory: Competing through Cellular Manufacturing'', New York: Productivity Press. p 41.〕 As just one testament to the commonality of the two terms, ''Toyota production system (TPS)'' has been and is widely used as a synonym for both JIT and lean manufacturing.〔Monden, Yasuhiro, ed. 1986. ''Applying Just in Time: The American/Japanese Experience''. Norcross, Ga.: Institute of Industrial Engineers. This collection of JIT articles includes multiple references to TPS.〕〔Womack, J.P. and D. Jones. 2003. ''Lean Thinking: Banish Waste and Create Wealth in Your Corporation''. Revised. New York: Free Press. Numerous references to both lean and TPS.〕 ==Concept== The nature of just-in-time, meaning JIT manufacturing/production or JIT in any other setting (e.g., administration〔Billesbach, Thomas J. 1987. ''Applicability of Just-in-Time Techniques in the Administrative Area''. Doctoral dissertation, University of Nebraska. Ann Arbor, Mich., University Microfilms International.〕〔Jackson, Paul. 1991. White collar JIT at Security Pacific. ''Target''. 7 (1), Spring, 32–37.〕), may be reduced to four somewhat differently stated views. * Many have said that JIT revolves around wastes: "At its core, JIT is a ''waste-elimination'' philosophy . . . ."〔Hyer, Nancy, and Urban Wemmerlöv. 2002. op. cit., p 40.〕 Among the earliest writings on the matter, Shingo lists, as the "7 wastes," the wastes of: over-production, waiting, transportation, processing itself, stocks (), motion, and making defective products.〔Shingo, Shigeo. 1981. ''Study of 'TOYOTA' Production System from Industrial Engineering Viewpoint''. Tokyo: Japan Management Association. 287–291.〕 * Others have equated JIT production with ''kanban''. For example, one book has both kanban and just-in-time in its main title.〔Japan Management Association, ed. D.J. Lu trans. 1985. ''Kanban: Just-in-Time at Toyota: Management Begins at the Workplace''. Stamford, Ct.: Productivity Press.〕 * Still others assert that JIT's main aim is ''elimination of inventories'', although Murray maintains that "JIT is defined as 'NOT an inventory control system—but a way of thinking, working and management to eliminate wastes in the manufacturing process'.〔Murray, John. Manufacturing excellence through JIT, p 101-103, in Mortimer, J. ed. 1986. ''op. cit''.〕 In keeping with that view, JIT manufacturing has often been referred to in contrast to the more conventional just-in-case (JIC) mode: JIC keeps extra inventories to be used in case of disruptions (e.g., scrap, rework, equipment breakdowns, late deliveries), whereas JIT continually reduces such inventory buffers by continually attacking causes of disruptions.〔Suri, R. 1986. Getting from ‘just in case’ to ‘just in time’: insights from a simple model. 6 (3) 295–304.〕 ''Zero Inventories'' is the title of a 1983 book by Hall,〔Hall, R.W. 1983. op. cit.〕 but the book actually does not suggest that JIT is mainly about inventory; rather the book features quick setup, cells (group technology), kanban, and so on, and zero inventory is posed only as an unattainable ideal, one that is easy to see and count. * The fourth view is that JIT is mainly about ''quick response'', relating to the "T"—for "time"—in JIT. As Blackburn put it, "Quick response is one of the major benefits of JIT. Time or speed is the linchpin of this manufacturing philosophy. Inventory, on the other hand, is an ancillary benefit."〔Blackburn, Joseph T. 1991. ''Time-based Competition: The Next Battleground in American Manufacturing''. Homewood, Ill.; Business One Irwin, p 28.〕 Quick response refers alternatively to reduction of cycle times,〔Thomas, P.R. 1991. Getting Competitive: Middle Managers and the Cycle Time Ethic. New York: McGraw-Hill.〕 flow times, throughput times, and, all the way to the customer, lead times: "JIT," according to Bicheno, has the "provocative goal," of producing "instantaneously, with perfect quality and minimum waste," and he goes on to qualify "instantaneously" by saying, "The ideal way to produce the end product is literally just in time to meet the market demand for it. Thus, JIT is primarily a lead-time reduction programme."〔Bicheno, J.R. 1987. A framework for JIT implementation. in Voss, C.A., ed. 1987. ''op. cit''. pp 191–204.〕 The four JIT views—referring to wastes, kanban, inventory, and quick response/lead-time reduction—do not suggest opposing views, but rather appear to be complementary points of emphasis, collectively serving to describe the essence of JIT. Aside from the four viewpoints, Just in time has often been paired with total quality control, forming the acronym, JIT/TQC.〔Hohner, Gregory. 1988. JIT/TQC: integrating product design with shop floor effectiveness. ''Industrial Engineering''. 20 (9) (Sept. 1988), 42–48.〕〔Goddard, W.E. 2001. JIT/TQC—identifying and solving problems. ''Proceedings of the 20th Electrical Electronics Insulation Conference'', Boston, October 7–10, 88–91.〕〔Hum, Sin-Hoon. 1991 Industrial progress and the strategic significance of JIT and TQC for developing countries. ''International Journal of Operations & Production Management''. 110 (5) 39–46.〕 The rationale is that TQC avoids stoppages and slowdowns disruptive to the quick-flow aims of JIT; and JIT exposes quality issues and their causes soon after they occur, thus facilitating their elimination. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Just-in-time manufacturing」の詳細全文を読む スポンサード リンク
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