KD1100中型載貨汽車設(shè)計(jì)-離合器及傳動(dòng)軸設(shè)計(jì)【4張CAD圖紙+外文翻譯+畢業(yè)論文】
33頁 14900字?jǐn)?shù)+論文說明書【詳情如下】
KD1100中型載貨汽車設(shè)計(jì)-離合器及傳動(dòng)軸設(shè)計(jì)說明書.doc
傳動(dòng)軸.dwg
外文翻譯--選擇中國汽車工業(yè)的發(fā)展模式.doc
摘要.doc
目錄.doc
離合器壓盤.dwg
離合器總成裝配圖.dwg
膜片.dwg
目 錄
第一章 前 言…………………………………………………………………1
第二章 離合器概述…………………………………………………………2
§1.1 離合器的主動(dòng)部分……………………………………………………2
§1.2 離合器的工作原理……………………………………………3
第三章 離合器設(shè)計(jì)計(jì)算………………………………………………6
§3.1離合器設(shè)計(jì)要求……………………………………………6
§3.2離合器參數(shù)的選擇…………………………………………6
§3.3從動(dòng)盤總成………………………………………………10
§3.4壓盤和離合器蓋計(jì)算…………………………………………12
§3.5 膜片彈簧的設(shè)計(jì)計(jì)算……………………………………………15
§3.6 扭轉(zhuǎn)減震器計(jì)算………………………………………………17
§3.7 離合器操縱系統(tǒng)設(shè)計(jì)…………………………………………18
§3.8 離合器試驗(yàn)……………………………………………………18
§3.9 國外離合器發(fā)展………………………………………………18
第四章 傳動(dòng)軸計(jì)算……………………………………………………………21
§4.1 萬向傳動(dòng)的計(jì)算載荷…………………………………………………21
§4.2 十字軸設(shè)計(jì)計(jì)算………………………………………………………22
§4.3 十字軸滾針軸承的計(jì)算………………………………………………23
§4.4 萬向節(jié)叉的設(shè)計(jì)計(jì)算…………………………………………………24
§4.5 傳動(dòng)軸臨界轉(zhuǎn)速計(jì)算…………………………………………………27
§4.6 軸管強(qiáng)度計(jì)算…………………………………………………………29
§4.7 傳動(dòng)軸花鍵軸的計(jì)算…………………………………………………29
第五章 結(jié) 論…………………………………………………………………31
參考文獻(xiàn)…………………………………………………………………32
致 謝………………………………………………………………………33
外文翻譯…………………………………………………………………34
KD1100中型載貨汽車設(shè)計(jì)
—離合器及傳動(dòng)軸設(shè)計(jì)
摘 要
本次設(shè)計(jì)了離合器和傳動(dòng)軸。在汽車傳動(dòng)系的這些部件中，離合器和傳動(dòng)軸是其中兩個(gè)重要的部件。在傳動(dòng)系統(tǒng)中，離合器位于發(fā)動(dòng)機(jī)與變速器之間，其作用是使駕駛員可以把發(fā)動(dòng)機(jī)與變速器接合或分離。離合器是一種摩擦式分離裝置，與駕駛室中離合器踏板相連接。駕駛員通過操縱離合器既可以使發(fā)動(dòng)機(jī)與離合器暫時(shí)分離，也可以在汽車起步時(shí)使發(fā)動(dòng)機(jī)與離合器平穩(wěn)接合。本次設(shè)計(jì)為膜片彈簧離合器。
本設(shè)計(jì)通過對傳動(dòng)軸的傳動(dòng)類型分析，結(jié)合所設(shè)計(jì)中型載貨汽車的特點(diǎn)以及市場趨勢等因素，對傳動(dòng)方式和傳動(dòng)軸進(jìn)行了選型；通過對傳動(dòng)軸的類型與結(jié)構(gòu)分析，選擇傳動(dòng)軸的十字軸滾針軸承的密封形式為蓋板式密封，并在其密封部位采用橡膠骨架油封和氈圈油封相結(jié)合的密封形式，以適應(yīng)農(nóng)村地區(qū)的惡略路況；通過對萬向節(jié)的十字軸 、滾針軸承 、萬向節(jié)差的設(shè)計(jì)計(jì)算，確定了所設(shè)計(jì)車輛使用的這些部件的具體尺寸；通過對傳動(dòng)軸的臨界轉(zhuǎn)速和計(jì)算載荷的確定，用待定系數(shù)法確定了傳動(dòng)軸的花鍵軸和軸管的尺寸，并校核了其扭轉(zhuǎn)強(qiáng)度和臨界轉(zhuǎn)速，確定了合適的安全系數(shù)。鑒于矩形花鍵的一系列優(yōu)點(diǎn)和國內(nèi)的生產(chǎn)加工水平，傳動(dòng)軸花鍵采用了矩形花鍵。傳動(dòng)軸的實(shí)驗(yàn)室傳動(dòng)軸的生產(chǎn)加工中的一項(xiàng)至關(guān)重要的程序，本文在該書中對傳動(dòng)軸的試驗(yàn)進(jìn)行了簡要介紹，并且在設(shè)計(jì)過程中對涉及到實(shí)驗(yàn)的部分有針對性查閱了同類型的產(chǎn)品的試驗(yàn)結(jié)果，對設(shè)計(jì)結(jié)果予以修正。綜合各部分的設(shè)計(jì)及校核結(jié)果，所設(shè)計(jì)的傳動(dòng)軸能滿足所設(shè)計(jì)的中型載貨汽車的傳動(dòng)要求。
關(guān)鍵詞：離合器, 摩擦式, 膜片彈簧, 傳動(dòng)軸, 十字軸
KD1100MEDIUM-LADEN CAR
—CLUTCH AND PROPELLER SHAFT DESIGN
ABSTRACT
In this thesis ,clutch and propeller shaft is designed .The clutch and the transmission are two important units of all .The clutch is located in the power train between the engine and the transmission .Its purpose is to permit the driver to coupe or uncouple the engine and transmission .The clutch is a friction-type device .It is linked to a clutch pedal in the driver’s compartment .The clutch allows the driver to couple the engine or uncouple the engine from transmission while he is shifting gears or starting the automobile moving rest .In the design ,we use the type of coil-pressure-spring .
The thesis introduced power transmission shaft used on farming transporters. According to the features of the farming transporter and the characters of the road in rural areas ,we chose the simply made open style power transmission shaft .For farming transporters , its cost and convenience for reparation and adaptability rather than its comfort ability and science ratio are concerned .So during the design we did not pay too much attention to the popular which is often advanced technology of the filed .On the contrary ,we just made some necessary improvement to the using form .For example ,we use involutes serration instead of rectangle serration ,so the durability of the spine will be much upgraded while its cost still low because nowadays its not more difficult to machine involutes serration than rectangle serration .To up the durability of the shaft ,we paid much attention to the seal form of the unit .We used rubber bone seal together with felt washer .
KEY WORDS：clutch, friction-type, Diaphragm spring, power transmission shaft, cross axle
第一章 前 言
隨著汽車工業(yè)的發(fā)展,離合器也在原有的基礎(chǔ)上不斷改進(jìn)和提高,以適應(yīng)新的使用條件。從國外的發(fā)展動(dòng)向來看,汽車的性能在向高速發(fā)展,發(fā)動(dòng)機(jī)的功率和轉(zhuǎn)速不斷提高,載重汽車趨于大型化,國內(nèi)情況也類似于此。另外,離合器的使用條件也日酷一日。因此,增加離合器的傳扭能力,提高其使用壽命,簡化操作已成為離合器目前發(fā)展的趨勢。
離合器的結(jié)構(gòu)形式雖然可以各不相同,但在使用中對它們的基本要求卻是一致的。對汽車離合器的基本要求有以下幾點(diǎn): ①能可靠地傳遞發(fā)動(dòng)機(jī)的最大扭矩; ②接合時(shí)要平順、柔和,使汽車起步時(shí)沒有抖動(dòng)和沖擊; ③分離時(shí)要迅速徹底; ④離合器從動(dòng)部分的轉(zhuǎn)動(dòng)慣量要小,以減輕汽車起步和換檔時(shí)變速器齒輪輪齒間的沖擊,方便換檔; ⑤離合器的通風(fēng)散熱應(yīng)良好; ⑥高速回轉(zhuǎn)時(shí)要具有可靠的強(qiáng)度,應(yīng)注意平衡問題和離心力的影響; ⑦應(yīng)使汽車傳動(dòng)系避免共振,并具有吸收振動(dòng),緩和沖擊和減少噪音的能力; ⑧操縱輕便; ⑨離合器的工作性能應(yīng)保持穩(wěn)定,這就要求作用在摩擦片上的總壓力要不因摩擦表面的磨損而變化,或者變化較小; ⑩要求使用壽命長。此外,離合器也要盡量做到結(jié)構(gòu)簡單,緊湊,制造工藝性好,維修方便,重量輕等等。
基于上述要求,離合器的壓緊彈簧從普遍采用的圓柱螺旋彈簧改為膜片彈簧,其利甚多。首先,膜片彈簧本身兼起壓緊彈簧和分離杠桿的作用,使零件數(shù)量減少,重量減輕,離合器結(jié)構(gòu)大為簡化,并顯著地縮短了離合器的軸向尺寸。其次,由于膜片彈簧與壓盤以整個(gè)圓周接觸,使壓力分布均勻,摩擦片的接觸良好,磨損均勻,再者,由于膜片彈簧具有非線性的特性,因此,可設(shè)計(jì)成當(dāng)摩擦片磨損后,彈簧壓力幾乎可以保護(hù)不變,且可減輕分離離合器時(shí)的踏板力,使操縱輕便。另外,膜片彈簧的安裝集團(tuán)對離合器軸的中心線來說是對稱的,因此它的壓緊力實(shí)際上不受離心力的影響。
膜片彈簧與螺旋彈簧的對比：
1、 制造工藝方面 膜片彈簧由彈簧鋼板沖制而成,而螺旋彈簧由鋼絲卷繞而成,相比之下前者制造工藝性好。
2、 零件數(shù)量方面 膜片彈簧本身帶有分離爪,勿須另加分離桿,且一個(gè)離合器只用一張膜片彈簧作為壓緊彈簧;而螺旋彈簧要另加分離桿,且一個(gè)離合器要用若干個(gè)螺旋彈簧作為壓緊彈簧。相比之下前者零件數(shù)量少,結(jié)構(gòu)緊湊;后者零件數(shù)量多。零件數(shù)量少者,拆裝、維修方便省時(shí);零件數(shù)量多則費(fèi)時(shí)。
3、其他方面
(1) 螺旋彈簧其彈性特性為線性的,因此離合的調(diào)整比較容易。而膜片彈簧其彈性特性為非線性的,因而離合器的調(diào)整較困難。不過,適當(dāng)選取H/ h 的值,適合汽車離合器使用的膜片彈簧總可以制造出來,只要我們掌握了膜片彈簧的特性,離合器調(diào)整問題也可隨之解決。
(2) 膜片彈簧的制造成本比圓柱螺旋彈簧的制造成本高一些,但壽命也比螺旋彈簧長一些。另外,膜片彈簧不受離心力的影響,而螺旋彈簧要受離心力影響,特別是高速旋轉(zhuǎn)時(shí),其影響不可忽視。
現(xiàn)代汽車向高速發(fā)展,離合器也向高速發(fā)展,壓緊彈簧在高轉(zhuǎn)速下工作,膜片彈簧的優(yōu)越性會(huì)隨之顯示出來。膜片彈簧取代螺旋彈簧作為離合器壓緊彈簧勢所必然。第五章 結(jié) 論
在本次設(shè)計(jì)的整個(gè)過程中，首先要做的是對所設(shè)計(jì)整車有一個(gè)全面的、系統(tǒng)的、整體的認(rèn)識，明確各自的任務(wù)以及與整車設(shè)計(jì)過程中的聯(lián)系。在這次設(shè)計(jì)中，我個(gè)人承擔(dān)了離合器及傳動(dòng)軸連部分的設(shè)計(jì)任務(wù)。
離合器是汽車傳動(dòng)系中的重要組成部分它的性能好壞直接影響整車的整體性能。在本次設(shè)計(jì)中，首先對離合器的類型和各自的特點(diǎn)進(jìn)行分析，然后結(jié)合所設(shè)計(jì)整車的性能要求確定離合器的結(jié)構(gòu)型式。接下來根據(jù)所確定離合器的形式，按照離合器設(shè)計(jì)要求，對每個(gè)零件進(jìn)行設(shè)計(jì)計(jì)算。其中最重要的是確定離合器的后備系數(shù)、摩擦片的內(nèi)外徑大小、從動(dòng)盤轂連接花鍵齒、壓盤厚度以及離合器蓋等的各個(gè)參數(shù)。并在計(jì)算過程中，注重個(gè)零部件之間的相互聯(lián)系，即滿足相互之間的約束條件關(guān)系。本次設(shè)計(jì)的膜片彈簧離合器經(jīng)計(jì)算校核能夠滿足所需設(shè)計(jì)要求。
傳動(dòng)軸同離合器一樣，在汽車傳動(dòng)系中起著重要的作用。傳動(dòng)軸設(shè)計(jì)過程中最重要的就是傳動(dòng)軸的動(dòng)平衡以及臨界轉(zhuǎn)速的校核。此次設(shè)計(jì)的中型載貨汽車，根據(jù)其使用要求和使用條件，同時(shí)參考同類車型的設(shè)計(jì)特點(diǎn)。在設(shè)計(jì)中采用十字軸式萬向節(jié)。通過一系列參數(shù)的計(jì)算和校核，十字軸式萬向節(jié)能夠滿足設(shè)計(jì)的要求。傳動(dòng)軸連接花鍵的設(shè)計(jì)也是設(shè)計(jì)過程中重要的一環(huán)?；ㄦI齒強(qiáng)度和有效接合長度直接決定傳動(dòng)軸是否能夠有效地傳遞轉(zhuǎn)矩。因此在設(shè)計(jì)中對傳動(dòng)花鍵進(jìn)行設(shè)計(jì)計(jì)算之后，要進(jìn)行必要的校核，以確定其能滿足設(shè)計(jì)需要。
此次設(shè)計(jì)，是對以前所學(xué)知識的一次全面回顧和掌握的過程，同時(shí)也是對運(yùn)用所學(xué)知識解決實(shí)際問題的一次鍛煉。在設(shè)計(jì)過程中，是我認(rèn)識到了自己知識的缺乏，使我明白了在以后工作過程中不斷學(xué)習(xí)的重要性。由于自身知識和能力的限制，此次設(shè)計(jì)難免存在不足之處。例如，某些計(jì)算部分不夠完整，計(jì)算數(shù)據(jù)不夠合理，整體設(shè)計(jì)不夠合理等。特別是傳動(dòng)軸部分的設(shè)計(jì)，由于整體布置和其它傳動(dòng)部分設(shè)計(jì)不夠緊湊，造成傳動(dòng)軸部分空間長度過短，使傳動(dòng)軸實(shí)際長度較短，給生產(chǎn)和加工造成困難。這些都有待日后進(jìn)一步的學(xué)習(xí)提高。
參考文獻(xiàn)
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致 謝
此次設(shè)計(jì)，是對以前所學(xué)知識的一次全面回顧和掌握的過程，同時(shí)也是對運(yùn)用所學(xué)知識解決實(shí)際問題的一次鍛煉。在設(shè)計(jì)過程中，是我認(rèn)識到了自己知識的缺乏，使我明白了在以后工作過程中不斷學(xué)習(xí)的重要性。由于自身知識和能力的限制，此次設(shè)計(jì)難免存在不足之處。例如，某些計(jì)算部分不夠完整，計(jì)算數(shù)據(jù)不夠合理，整體設(shè)計(jì)不夠合理等。
在設(shè)計(jì)中，老師提出的要求和建議使我們學(xué)到了如何認(rèn)真的對待一項(xiàng)工作，也使我們養(yǎng)成了對待任何事情都要認(rèn)真、嚴(yán)肅的態(tài)度，同時(shí)也使我們學(xué)會(huì)了如何在工作中克服浮躁心理。李水良老師本人治學(xué)嚴(yán)謹(jǐn)?shù)膽B(tài)度給我們留下了非常深刻的印象，從他的身上我們學(xué)到了許多課本上學(xué)不到的寶貴經(jīng)驗(yàn)，這一切使我們受益匪淺。此外，在本次設(shè)計(jì)中，我得到了同班其他同學(xué)的大力幫助，更得到了車輛研究所多位老師的熱情指導(dǎo)，他們給我提供了許多寶貴的建議，在這里特此以我向他們致以最誠摯的謝意！再次感謝設(shè)計(jì)過程中關(guān)心和幫助過我的老師和同學(xué)！感謝參與評審的老師！
英文翻譯Options for the Development Pattern of China’s Automobile IndustryI. Why is China’s Automobile Industry Not Competitive? Of the many industries in China, auto industry does not develop fast and is not competitive. There are many reasons that lead to this situation. But the main reason is that it has not experienced a complete process of market opening and competition. This will be clearer after being compared with the development of other industries.Since the reform and opening-up, China has seen some fast-developing industries, especially the household electrical appliance industry. In spite of many problems, they are generally healthy and dynamic, and outperform other industries in product upgrading, technological progress, quality, service and guaranteeing consumers’ rights. They will be most competitive even after China’s entry into WTO. The sound development of these industries should be mostly attributed to the fact that they have experienced a process of market opening and intensive competition, thus solving the three key problems crucial to the development of an industry: First, the “discovery” of advantageous enterprises. The advantageous enterprises are not born by nature, self-styled or designated by the government. They must experience a process of being “screened” through competition before being “discovered”. Any individuals or organizations including the governments cannot foretell which enterprises are advantageous enterprises. Today’s advanced enterprises were once not sure whether they would surely succeed today. This is determined by the competition on the market.Second, the learning and training of enterprises’ competitiveness. “Competitiveness can only be acquired through competition” is a basic tenet. An enterprise’s marketing, management, R&D and financing abilities can only be acquired and accumulated from the twists and turns in the course of competition, and consequently, the organization, mechanism and system of an enterprise can be gradually improved as well. The scale and competitiveness of an enterprise are not only a technical concept. More importantly, it is related to system and mechanism. Third, the exploration and use of market potentials. Competition helps enterprises reduce costs and prices, raise product quality, improve services, promote new products and turn great potential need to realistic demand. Automobile and electrical appliance industries, both belonging to processing, assembling and manufacturing industries, are similar in terms of technological and market structure, for instance, they both have a high demand for scale economy and develop into highly industrial concentration as a result of competition. However, auto industry has not shown the active development momentum and competitiveness like household electrical appliance industry. This is largely because the former has not experienced a full process of market opening and competition. From the view of policy, we should, in particular, reflect on and examine the strict policy on market access and the restrictive consumption policy. Due to strict limitation on market access, in addition to the restriction on the model, variety and specification of automobiles, the competition is not complete and limited, although China has more than 100 car plants. The restrictive consumption policy has prevented the existing market demand from being unleashed, and at the same time, placed the insufficient production capacity in surplus. II. “Establishing the Competitive Edge as a Big Country in the Course of Opening”: The Option for the Development Pattern of China’s Auto Industry under the New Situation.The development pattern of China’s auto industry under the new situation should proceed from the current domestic and international condition and be based on current and potential advantages. China should learn from the international experiences in the development of auto industry, especially those of the newly developed countries, for making options that conform to the law of development. We believe this pattern could be summarized by “establishing the competitive edge as a big country in the course of opening”.This means, firstly, we should base ourselves on opening. To put it specifically, we should gradually integrate the auto industry into the system of international working division under the framework of WTO so as to adapt to and make use of, not reject, the trend of globalization of auto industry. As a rising developing country, China certainly needs some necessary protection over some of its industries. Instead of relying on the protection, it should take an active part in extensive and in-depth international competition and cooperation. Secondly, China should make full use of and cultivate its own advantages. At the present stage, the advantages of China’s auto industry include the overall capability of the manufacturing industry, labor cost and the large market in a big country. These advantages are the comparative advantages according to the theory of economics. But in many cases, comparative advantages are not equal to competitive advantages. The key is to adjust the system, strategy and policies under the opening policy in order to turn the realistic and potential comparative advantages to competitive advantages. Thirdly, the advantage of a large market in a big country is most important. First of all, China’s huge market will yield the effect of scale economy in various links of the auto industry chains. This will mainly be reflected in car assembling and production of some spare parts. And the demand for independent R&D that meets the need of Chinese market will therefore arise. Next, China’s domestic market can accommodate several strong transnational corporations. At the same time, it can also provide space large enough for a large number of domestic enterprises and enterprises with domestic capital. Finally, Chinese market is not only large, but also appears to be obviously multi-layered, which is conducive to the domestic enterprises that started late and are still developing. To be specific, the new development pattern should include the following features: 1. Cultivating a domestic market with active and full competitive environment. Compared with the production and sale capacity of more than 10 million automobiles in the future 20 to 30 years, China’s current auto industry with manufacturing and marketing capacity of more than 2 million cars is still at an infant stage now. Therefore, there will be a necessary, possible, to put it more precisely, unavoidable process of competition designed to select advantageous enterprises, raise enterprises’ competitiveness and explore the market potentials. Due to market access barriers on investment scale and technologies on the current industrial basis, the gradual entry of transnational corporations and the government’s rational policy guidance, competition within the auto industry may take on different characteristics from that in the electrical appliance industry, and the process of competition spurring the industrial growth could be shortened. The urgent task is to foster a domestic environment of active and full competition. The limitation on industrial access should be drastically relaxed; as the government’s direct investment stops, various responsible investors including non-state investors should be allowed to enter the industry; the administrative monopoly by departments and regions should be further done away with so as to form an open and unified domestic market; competition order should be regulated, and new systems should be built to restrict activities that hamper positive competition. The basis of and key to the successful new development pattern is a market with active and full competition, without which development will hardly go on. If this foundation could be laid well, we will have every reason to predict that in a short period of time (five years or longer), China will have a batch of competitive enterprises with initial international competitiveness, which include joint venture enterprises, solely-foreign invested enterprises, domestic enterprises and enterprises with domestic capital. 2. Several transnational corporations will enter into Chinese market while outstanding domestic enterprises develop on their own. One important policy orientation is that supporting the entry of transnational corporations will be a component of the country’s global strategy. When the tariff rates are drastically reduced after China’s entry into WTO, the transnational corporations will have two choices: first, exporting cars to China, second, building factories and manufacturing cars in China. Our policy should clearly avoid large-scale car imports, or large-scale cars assembling with low added value for the Chinese market. After China’s entry into WTO, we should relax or abolish the restriction on the equity and localization rate set for foreign investors at a proper time so that they would make industrial transfer to China out of the consideration of global strategy. They should be specially encouraged to export cars and parts from China. The other policy orientation is to encourage the positive competition between transnational corporations in China. The experience of many industries has proved that such competition is extremely important to product upgrading, speeding up transnational corporations’ transfer of technologies to China, improving management and reducing costs. On the other hand, we should encourage domestic enterprises and enterprises with domestic capital to cultivate their core competitiveness and support them to cooperate with foreign-invested enterprises in various forms (not just joint venture), especially their effort in developing, upgrading and enlarging the scale of R&D, brand building and marketing system. The entry of transnational corporations does not conflict with the independent development of domestic enterprises and enterprises with domestic capital. The Chinese market can provide sufficient space for both of them. They will surely compete with each other, but more often, they will cooperate, unite and merge, eventually raising the overall competitiveness of China’s automobile industry.3. Gradually integrating into the world’s work division system of automobile industry in the course of opening, and taking the improvement of international competitiveness and realization of net export as the mid- and long-term objectives. We should change the ideas and practice of confining the industrial chains in the country (even within an area) and mainly relying on domestic market and resources, gradually integrate the auto industry into the global system of purchasing, manufacturing, marketing and R&D in order to make good use of domestic and international markets and resources. We should completely give up the goals of substituting imports with domestic-made products. We will import and export cars, concentrate our efforts in developing the products with market and resource advantages while importing some products that China does not produce or has no advantages, such as luxurious automobiles. As the country’s auto market is large and still developing, it can support large-scale car-assembling production mainly aimed at the domestic market and demonstrate the positive effect of scale economy. On this basis, the fast growth of entire cars and auto parts with international competitiveness could well be expected. From the mid- and long-term point of view, we should strive to realize the net export of automobiles at a very high level of opening and gradually increase its share in the global market. This means that China will not only be the largest potential consumer, but also a strong car processor and manufacturer with fairly strong competitiveness. 4. The mid-term development strategy is focused on economical household automobiles. Firstly, this strategy targets at the demand at the initial development stage of the automobile market, where the household automobiles will be the focus with the greatest demand for economical household cars. Secondly, the strategy will be beneficial to the involvement of new enterprises and cultivation of competitiveness. The demand for technologies, management, funds and talent from the development of economical household cars is relatively low, or there exists less access hindrance. This is a rare opportunity (maybe the last opportunity) for the domestic enterprises or enterprises with domestic capital. Of course, economical household cars don’t necessarily mean low level of technology and quality. With the change of market demand and the development of enterprises, there will be much room for improvement in technology and quality. Thirdly, if China has developed a fairly large scale of economical household car production with certain competitiveness, it will have a good market opportunity in the international market, especially in the market of adjacent emerging countries. 5. Reorganization of auto part industry oriented towards the global market. On the one hand, China’s auto part enterprises, affected by the domestic policy that requires the high localization rate of cars, are mainly catering to the domestic market. On the other hand, in enterprise organization, they usually include auto part production and car production in an enterprise group. The auto part production mainly meets the need of car production. So these enterprises are plagued by small product batches, high costs and low technological development ability. This has not only seriously restricted the development of auto part industry, but also increased the cost of the whole industry. The objective of reorganizing the auto part industry is to adjust the relationship between car enterprises and auto part enterprises so that the car factories are able to select good auto parts from all the enterprises. The auto part enterprises can supply parts to all the car factories through competition. The objective of the first phase of the reorganization is to free the auto part factories from the restriction of enterprise groups and regions so that the enterprises in good conditions would speed up reorganization and build up capability in order to become nationwide suppliers. Then the objective of the second phase is to actively take part in the transnational reorganization. With the help of transnational corporations’ global purchase and marketing network plus their own efforts, a number of competitive auto part enterprises will gradually become global suppliers. In the middle and long run, the proportion of China’s auto part import and export should be higher than that of cars. In this course, the number of auto part enterprises will be reduced comparatively while the large auto part enterprises characterized by modularization and systematization will increase. There will be a huge development space for international auto part corporations and competitive domestic auto part enterprises. 6. Transferring towards the top of industrial value added chains step by step. In terms of technological content and added value, the late-coming countries have basically experienced four phases in their auto industry development -- imports, KD assembling, introduction of technologies and production of scale, and turning to maturity. At present, China’s auto industry is basically at the stage with the characteristics of the second and third phases. Raising technological development and value adding capability of the industry should be the objective for the new development pattern. But in general, we should follow the track of transferring towards top of industrial value added chains by phases. The large-scale production based on the large-country market will make transnational corporations transfer part of their R&D capability to China. The R&D that meet China’s specific demand will be prioritized. The competition between transnational corporations will also help speed up the transfer of technology. Secondly, this move, identical with the strategy of developing economical household cars, should seek a technological breakthrough and develop a certain degree of advantage. At the same time, with the reorganization of auto part enterprises, we should speed up improving the R&D capability and develop international competitiveness in some auto part products. Thirdly, as the auto industry is more mature and its degree of internationalization is higher, especially with the progress of R&D talent, the domestic technological development forces will be more involved in the international work division of R& D and become a more and more important part of it.選擇中國汽車工業(yè)的發(fā)展模式為何中國汽車行業(yè)缺乏市場競爭？在中國有許多產(chǎn)業(yè)，汽車工業(yè)是發(fā)展較慢且缺乏市場競爭。這里存在許多導(dǎo)致這種現(xiàn)狀的原因，但最主要的原因是沒有經(jīng)歷一個(gè)市場開放和充分競爭的過程。拿它與其它發(fā)展行業(yè)相比是不難看出的。改革開放以來，我國出現(xiàn)了一批發(fā)展快、競爭力強(qiáng)的產(chǎn)業(yè)， 最具典型性的是家電盡管這一產(chǎn)業(yè)也存在著諸多問題，時(shí)常受到這樣那樣的批評，但總體上是健康而富有活力的，在產(chǎn)品更新、技術(shù)進(jìn)步、質(zhì)量和服務(wù)、消費(fèi)者受益等方面比其他產(chǎn)業(yè)表現(xiàn)得更為突出，中國“入世” 后也是最具競爭力的產(chǎn)業(yè)。這批產(chǎn)業(yè)之所以發(fā)展得較好，最值得強(qiáng)調(diào)的是其經(jīng)歷了一個(gè)市場開放和充分競爭的過程。正是經(jīng)由這個(gè)過程，解決了對一個(gè)產(chǎn)業(yè)發(fā)展至為關(guān)鍵的三個(gè)問題： 第一，優(yōu)勢企業(yè)的“ 發(fā)現(xiàn)”問題。優(yōu)勢企業(yè)不是天上掉下來的，也不是自封或由政府指定的，必須經(jīng)歷一個(gè)市場競爭的“篩選”過程才能被“發(fā)現(xiàn)” 。不論個(gè)人、政府及其他組織都不可能事先預(yù)知哪個(gè)企業(yè)是優(yōu)勢企業(yè)，今天的優(yōu)勢企業(yè)昨天或前天也不可能知道自己能夠成功。這是必須經(jīng)過市場競爭才能解決的問題。 第二，企業(yè)競爭力的學(xué)習(xí)和培養(yǎng)問題?！案偁幜κ峭ㄟ^競爭獲得的”是一個(gè)基本道理。企業(yè)的營銷、管理、研發(fā)、融資等等能力，只有在市場競爭的曲折經(jīng)歷中才能真正學(xué)到并積累下來，企業(yè)的組織、機(jī)制和制度才能隨著逐步完善。所謂“企業(yè)規(guī)模 ”及其競爭力，并不僅僅是技術(shù)概念，主要是體制和機(jī)制概念。一個(gè)經(jīng)過長期的市場摸爬滾打成長起來的年產(chǎn) 30 萬輛汽車的企業(yè)，與一個(gè)在計(jì)劃經(jīng)濟(jì)體制下由國家一次性投資建成的同樣年產(chǎn) 30 萬輛企業(yè)的企業(yè)，肯定不是一回事。 第三，市場潛力的發(fā)掘和利用問題。競爭促進(jìn)企業(yè)降低成本和價(jià)格，提高產(chǎn)品質(zhì)量和服務(wù)，促進(jìn)新產(chǎn)品普及，從而增加經(jīng)濟(jì)學(xué)上說的“消費(fèi)者剩余”，老百姓買得起，用的滿意或比較滿意，大量的潛在需求得以轉(zhuǎn)化為現(xiàn)實(shí)需求。 汽車產(chǎn)業(yè)與家電產(chǎn)業(yè)同屬組裝加工制造類產(chǎn)業(yè)，在技術(shù)和市場結(jié)構(gòu)性質(zhì)上相近，如對規(guī)模經(jīng)濟(jì)有較高要求，經(jīng)過市場競爭后較高的產(chǎn)業(yè)集中度等。然而，汽車產(chǎn)業(yè)并沒有表現(xiàn)出家電產(chǎn)業(yè)那種積極的發(fā)展態(tài)勢和競爭力，主要是因?yàn)闆]有經(jīng)歷一個(gè)市場開放和充分競爭的過程。從政策的角度說，尤其值得檢討和反思的是嚴(yán)格的市場進(jìn)入管制政策和抑制性消費(fèi)政策。由于嚴(yán)格的進(jìn)入限制，加上產(chǎn)品品種和價(jià)格管制、地方保護(hù)、封閉性強(qiáng)的企業(yè)體制，形式上看中國有一百多家整車廠，但競爭是很不充分和受到扭曲的。抑制性的消費(fèi)政策使已有的市場需求得不到釋放，同時(shí)也使事實(shí)上并不充裕的生產(chǎn)能力處于過剩狀態(tài)?！敖⒏偁帣C(jī)制是一個(gè)大國對外開放的開端”: 在新的形勢下選擇中國汽車工業(yè)的發(fā)展模式。在新形勢下，中國汽車工業(yè)的發(fā)展模式應(yīng)從當(dāng)前的國內(nèi)和國際形勢，并根據(jù)其當(dāng)前和潛在的有利條件來制定。中國應(yīng)該學(xué)習(xí)發(fā)達(dá)國家汽車工業(yè)先進(jìn)經(jīng)驗(yàn)，特別是那些新興的發(fā)達(dá)國家學(xué)習(xí)。制定自由競爭的法律依據(jù)。我們相信這一形式能概括為“建立選擇機(jī)制是作為一個(gè)大國對外開放的開端”。首先，這意味著我們應(yīng)該根據(jù)自己的實(shí)際情況對外開放。我們應(yīng)當(dāng)在世貿(mào)組織的相關(guān)協(xié)議的框架下參與到國際分工合作當(dāng)中，以充分適應(yīng)和利用汽車工業(yè)的全球化趨勢，而不是逃避這種趨勢。作為一個(gè)快速發(fā)展的發(fā)展中國家，中國需要對某些國內(nèi)行業(yè)有適度的保護(hù)政策，但不是依靠保護(hù)，而是應(yīng)該積極參與到國際競爭和合作當(dāng)中。第二，中國應(yīng)當(dāng)充分利用和培養(yǎng)自己的優(yōu)勢。當(dāng)前階段，中國的汽車工業(yè)優(yōu)勢包括制造工業(yè)的整體能力，勞動(dòng)力成本和國內(nèi)的廣大的市場。這些根據(jù)經(jīng)濟(jì)理論屬于比較優(yōu)勢。但在許多情況下，比較優(yōu)勢不等同于競爭優(yōu)勢。最重要的是在開放政策的條件下的調(diào)整機(jī)制，戰(zhàn)略和相關(guān)政策，來把實(shí)際的和潛在的比較優(yōu)勢轉(zhuǎn)變?yōu)楦偁巸?yōu)勢。第三，在一個(gè)大國有廣闊的市場是極為重要的。首先，中國巨大市場將帶動(dòng)與汽車相關(guān)的各行業(yè)產(chǎn)業(yè)鏈而產(chǎn)生規(guī)模經(jīng)濟(jì)。這件反映在汽車組裝和配件的生產(chǎn)上，并且對適應(yīng)中國市場需要的獨(dú)立 R&D 的需求間因此而出現(xiàn)。其次，中國的國內(nèi)市場競爭可同時(shí)容納幾個(gè)國際跨國公司。同時(shí)，它能提供大量過國內(nèi)企業(yè)和國內(nèi)資本發(fā)展空間。最后，中國國內(nèi)市場不僅很大，而且呈現(xiàn)出多層次發(fā)展，這對于國內(nèi)后來正在發(fā)展的企業(yè)是十分有利的。具體來說，新的發(fā)展模式應(yīng)包括以下特點(diǎn)：一、培養(yǎng)體格活躍和充分的國內(nèi)競爭環(huán)境。相對于未來 20 年到 30 年汽車超過上千萬的生產(chǎn)和銷售能力，中國目前的汽車生產(chǎn)能力合適場 200 萬輛的需求還處于起步階段。因此，有必要、并且有可能通過競爭來選擇優(yōu)勢企業(yè)，提升企業(yè)的競爭能力并且擴(kuò)大潛在市場需求。由于在投資規(guī)模市場進(jìn)入限制機(jī)制和當(dāng)前工業(yè)技術(shù)基礎(chǔ)，隨著跨國公司的進(jìn)入和政府合理的政策指導(dǎo)，汽車國內(nèi)工業(yè)可能呈現(xiàn)出不同于電器用品行業(yè)的發(fā)展特點(diǎn)。并且競爭激勵(lì)工業(yè)發(fā)展將被縮短。當(dāng)前迫切的任務(wù)是促進(jìn)一個(gè)具有活力和競爭的國內(nèi)環(huán)境。行業(yè)進(jìn)入限制應(yīng)當(dāng)盡快地解除，同時(shí)政府應(yīng)停止直接投資。各相應(yīng)的投資者，包括國外的投資者，應(yīng)允許進(jìn)入汽車行業(yè)。部門和地區(qū)壟斷應(yīng)進(jìn)一步廢除，以便形成一個(gè)統(tǒng)一和開放的國內(nèi)市場。競爭階段應(yīng)受到調(diào)控，并且新的機(jī)制應(yīng)建立以制約阻礙正面競爭的活動(dòng)。成功的發(fā)展模式的依據(jù)是一個(gè)具有活力和充分競爭的市場環(huán)境，否則很難進(jìn)一步發(fā)展。如果這個(gè)基礎(chǔ)能被打好，我們將有充分理由預(yù)言在一個(gè)短的時(shí)期（五年或更長），中國將有一批具有初步國際競爭力的企業(yè)，包括合資企業(yè)、外國獨(dú)資企業(yè)、國有企業(yè)和國有控股企業(yè)。二、當(dāng)優(yōu)勢的國有企業(yè)獨(dú)立發(fā)展時(shí)，一些跨國公司將會(huì)進(jìn)入中國市場。一個(gè)重要的政策取向是支持跨國公司的進(jìn)入。這將是國家全球性戰(zhàn)略的組成部分。當(dāng)中國加入世貿(mào)組織后，關(guān)稅將會(huì)大幅度降低，跨國公司將面臨兩個(gè)選擇：第一，對中國出口汽車。第二，在中國建廠并生產(chǎn)汽車。我們的政策是避免大量進(jìn)口汽車，或向市場大規(guī)模組裝低附加值的汽車。中國加入世貿(mào)組織后，我們應(yīng)放松或廢除對產(chǎn)權(quán)和地方化率的制約，以便于外國投資者出于全球戰(zhàn)略考慮而把行業(yè)轉(zhuǎn)向中國。我們應(yīng)當(dāng)鼓勵(lì)他們從中國出口整車和零部件。令體格政策取向是鼓勵(lì)跨國公司在中國積極競爭。許多行業(yè)發(fā)展經(jīng)驗(yàn)表明，競爭對于產(chǎn)品升級，加速跨國公司向中國技術(shù)轉(zhuǎn)移，改進(jìn)管理和減低成本是極端重要的。另一方面，我們應(yīng)當(dāng)鼓勵(lì)國有企業(yè)和國有控股企業(yè)培養(yǎng)他們核心競爭能力，支持他們與外資企業(yè)開展各方面合作（不僅僅是合資建廠），特別是他們在發(fā)展 、升級 和擴(kuò)大 R&D 的規(guī)模，建立品牌和市場機(jī)制方面?？鐕镜倪M(jìn)入不會(huì)與國內(nèi)企業(yè)獨(dú)立發(fā)展相沖突。中國市場能為兩者提供充足的發(fā)展空間。他們將互相競爭，但更多是相互合作，團(tuán)結(jié)和合并，最終提高中國汽車的整體競爭性。三、在開放期間，逐漸地加入到汽車工業(yè)的世界分工合作當(dāng)中，采取提升國際競爭力和實(shí)現(xiàn)凈出口作為中間和長期宗旨。我們應(yīng)當(dāng)改變觀念和改變把工業(yè)產(chǎn)業(yè)鏈限制在國內(nèi)（或在一個(gè)地區(qū)），并且主要依靠國內(nèi)市場和資源的做法。而應(yīng)逐步參與到汽車工業(yè)全球性購買 、制造 、營銷和 P&D 的體制中，以充分利用國內(nèi) 、國際市場和資源。我們應(yīng)該完全放棄以國內(nèi)產(chǎn)品替代進(jìn)口產(chǎn)品的目標(biāo)。我們將進(jìn)口和出口汽車，集中精力開發(fā)中國沒有進(jìn)口且國內(nèi)不生產(chǎn)或在中國沒有優(yōu)勢，而市場需求和有資源優(yōu)勢的產(chǎn)品。由于國內(nèi)汽車市場很大且處于發(fā)展階段，它能提供大規(guī)模以國內(nèi)市場為主的汽車組裝產(chǎn)品，并對規(guī)模經(jīng)濟(jì)產(chǎn)生積極影響。歌劇這個(gè)依據(jù)，整車和汽車零部件的國際競爭力的快速增長是可以預(yù)見的。從中長期的發(fā)展來看，我們應(yīng)當(dāng)努力實(shí)現(xiàn)汽車凈出口在一個(gè)相當(dāng)高的開放水平，并逐漸增加國際市場占有率。這意味著，中國不僅是最大的潛在消費(fèi)者，而且是一個(gè)具有相當(dāng)競爭力的汽車生產(chǎn)者和制造者。四、中期發(fā)展戰(zhàn)略集中于經(jīng)濟(jì)型家庭轎車。首先，這個(gè)戰(zhàn)略目標(biāo)在汽車市場最初需求的發(fā)展階段，那時(shí)家庭轎車將集中在巨大的家庭經(jīng)濟(jì)型轎車需求上。第二，這一戰(zhàn)略對新企業(yè)的進(jìn)入和培養(yǎng)競爭力是有利的。家庭型經(jīng)濟(jì)轎車對技術(shù) 、管理 、資金和人才的需求相對地降低，或哪里存在較少的限制。這是一個(gè)罕見的機(jī)會(huì)（可能是最后機(jī)會(huì)），對于國有企業(yè)或國有控股企業(yè)來說。當(dāng)