【正文】 故，綜上，棘輪滿足要求.同樣，可計算得棘爪也滿足要求.參考文獻[1]鮑際平，江軍，[J].北京汽車，2005，～43[2][M].北京：國防工業(yè)出版社，1998,60～71[3]（下冊）[M].北京：機械工業(yè)出版社，2005,～43[4]劉鴻文．材料力學(I)(II)．北京：高等教育出版社，2004,20～13[5]．第7版，北京：高等教育出版社，2001,2～108[6][M].北京：化學工業(yè)出版社，2002,90～101[7]（第六版）[M].北京：高等教育出版社，2002（2003重印）33～45[8]王安敏，張凱，[P].中國：，2006,71～73[9]張毅，潘可耕，：（P71）,53～56[10]王大康，：,88～96[11]:上?？萍技夹g出版社，2005，60～135[12]張洪欣．汽車設計．第1版，北京：機械工業(yè)出版社，1989，79～81[13] Machine Drive (Reference). Machine (14).1980,23~43[14]Hiroaki Kuroiwa, NaoyukiOzki. Nextgeneration Fuelefficient. Automated. Manual Transmission[15]Hiroaki HOSHINO. Simulationon Synchronization Mechanism of Transmission Gearbox附錄英文文獻Nextgeneration Fuelefficient Automated Manual TransmissionOVERVIEWFuel efficiency standards on vehicles are being increasingly strict to curb global warming, and Japan and Europe plan to reduce current standard values by about 25% in the timeframe from 2008 to 20101). Transmission manufacturers have responded with a range of proposals for enhancing fuel efficiency. A number of alternative schemes have been developed as a more fuelefficient nextgeneration transmission to succeed the existing ATs (automatic transmissions) and CVTs (continuously variable transmissions). One approach that is attracting considerable interest is an AMT (automated manual transmission), essentially an MT (manual transmission) with an automated control system. Hitachi Group is now developing a unique torqueassist AMT that is pactly implemented by adding a friction clutch mechanism to a conventional AT. Combining the fuel efficiency of an MT with the seamless shifting of an MT, this approach shows excellent promise as a pact and costeffective nextgeneration transmission.INTRODUCTIONMT (manual transmission) uses simple spur gears providing excellent transmission efficiency and thus typically get 10% or better fuel mileage than current ATs (automatic transmissions). The object of the AMT (automated manual transmission) is to automate the starting and gear shifting while retaining this excellent fuel efficiency. A round of fierce petition was triggered among European manufactures to see who would be the first to develop what is generally known as a conventional AMT that attempts to automate the shifting of MT. The problem with this design is that the drive torque is momentarily interrupted during shifting. This results in a very different shift feeling from an AT, and thus never saw widespread acceptance as a replacement for the conventional AT in mainstream vehicles. This was followed more recently by a twin clutch AMT that is receiving a great deal of attention.Supporting smooth and responsive shifting much like an AT, the twinclutch AMT has been installed by European vehicle manufacturer on some highenginecapacity sports cars beginning last fall. Hitachi Group is now developing an original torqueassist AMT that is fundamentally different from these other two approaches. In this paper we will highlight the objectives, the concept, and the primary features of the torqueassist AMT.Fig. 1—Hitachi’s Solution Technology for AMT Systems. Hitachi Group contributes to themanufacture of environmentallyfriendly vehicles through the development and deployment of innovative nextgeneration torqueassist AMT systems and integrated control technology enabling AMT systems to interwork smoothly with engine systems.OBJECTIVES AND FEATURES OF TORQUE ASSIST AMTIn order to achieve widespread acceptance as a replacement for conventional transmissions, the next generation transmission must provide the good fuel economy of an MT, the effortless shifting of an AT, and must also be pact and affordable. Unfortunately, the conventional AMT fails to achieve the seamless shifting of an AT and the twinclutch AMT is difficult to implement pactly and cost effectively. Hitachi Group has proposed a third way that does meet all the above requirements — a torqueassist AMT — and is now in the process of developing this system. A key advantage of this approach is that it can be implemented with relatively little modification to existing AMTs by simply adding a friction clutch called an assist clutch to the transmission. Action of the assist clutch effectively solves the torque interruption problem of the conventional AMT while providing the smooth gear shifting of an AT. A pact and economical torqueassist AMT could thus be implemented fairly easily for application on mainstream FF (frontengine frontdrive) pact vehicles with engine displacement under 2 liters.Operating principle and implementation of torqueassist AMTShifting OperationFig. 2—Outline and Principle of Operation for Torqueassist AMT. This new AMT transmits the engine torque to the wheels using the torqueassist mechanism during shifting, so an interruption of torque does not occurFig. 2 shows the shift timing of a 5speed manual gearbox with added assist clutch. The first half of a shift operation when upshifting from 1st to 2nd gear is illustrated in Fig. 2 (a). Transmitted torque from the assist clutch gradually increases until torque transmitted by 1st gear approaches zero. At this point, 1st gear is disengaged by the gear selectshift mechanism putting the transmission into neutral. In the next phase shown in Fig. 2 (b), torque is transmitted by 5th gear with assist clutch and controlled so that when the correct engine speed is reached to allow 2nd gear to mesh, the gear selectshift mechanism engages 2nd gear. Finally, the shift is plete in Fig. 2 (c) when transmitted torque from the assist clutch disappears and the torque transfer path only passes through 2nd gear.During this shifting sequence, there is no torque interruption, and the torque waveform closely approximates that of an AT. All up and downshift transitions are similarly smooth with this torqueassist AMT.System ConfigurationFig. 3—System Configura