1. 研究目的与意义（文献综述）

since the reform and opening up, china's auto industry development an-d application has been greatly improved. the automobile industry has become an important pillar industry in china, both in military, civilian and commercial, are playing an indispensable role. the car and its parts like the hu-man body and the various organs, is the organic combination of the whol-e. if the engine, wheels and chassis is the heart, limbs and torso, then the transmission is connected to the three of the blood. no blood flow, heart, limbs and torso no matter how good, but also over the plant people. therefore, we study the design of automotive transmission, not only for four years of theoretical knowledge of the university of a summary and promoti-on, the same can be more in-depth understanding of the car structure an-d performance.

china's gearbox market is facing enormous opportunities and challenge-s. on the one hand, china's rapid growth in automobile production and sal-es for the gearbox industry to provide opportunities and enhance the spac-e, china's auto sales in 2015 24.6 million, an increase of 4.7% in 2016 ch-ina's auto sales of 26.04 million, an increase of 6%. on the other hand, the rapid development of foreign automatic transmission technology to the domestic gearbox industry has brought great challenges. in the field of pass-enger cars, the current capacity to produce automatic transmission of dom-estic enterprises only auspicious, chery and other small enterprises, most dependent on imports. in the field of commercial vehicles, still can not use automatic transmission, and foreign countries have begun to use.

in north america, the three major us auto companies always adhere to the automatic transmission research, advanced six-speed transmission wi-ll make full use of the existing four-speed automatic transmission equipme-nt and foundation, and its fuel economy is also better. this is to meet the north american consumers not only focus on comfort, in the energy crisis under the fuel economy focus on the consumer concept.

2. 研究的基本内容与方案

this design g1092a2d2 long head diesel truck truck transmission, mediumsized truck manual six-speed transmission, the use of three-axis transmissi-on. the specific design process is as follows:

1. transmission structure of the program layout: transmission structure selection, reverse the type and layout program, the choice of gear type.

2. determination of the main parameters of the transmission: transmissi-on gear and gear ratio to determine the center distance to determine the gear ratio and gear teeth to determine the number of gear parameters of the calculation.

3. 研究计划与安排

week 1: program ideas, literature search, complete the opening report.

2 to 3 weeks: foreign language translation, data re-collection.

4 to 6 weeks: design calculations, sketching.

4. 参考文献（12篇以上）

[1] wang wangyu. automotive design. beijing: mechanical industry press, 2004.8 (2007.6 reprint).

[2] yu zhisheng. automotive theory. beijing: mechanical industry press, 2009.3.