基于UG的死飛自行車設(shè)計(jì)-運(yùn)動(dòng)自行車結(jié)構(gòu)設(shè)計(jì)【含7張cad圖紙+文檔全套資料】
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地方官員常用的這樣的借口來拒絕電動(dòng)自行車:鉛酸電池會污染環(huán)境;電動(dòng)車會干擾機(jī)動(dòng)車輛行駛,阻塞交通;特別是對公交系統(tǒng)造成巨大沖擊。積極為綠色交通奔走呼吁的請?jiān)溉耸空f,這些借口蒼白無力,不過是試圖去保護(hù)電動(dòng)車的競爭者而已。中國科學(xué)院著名理論物理學(xué)家,院士何祚庥一針見血地指出:“真正的原因就是來自利益集團(tuán)的競爭?!薄?
何院士在有關(guān)環(huán)境和能源政策的公共辯論中一向直言。他說反對電動(dòng)車的理由沒有一條真正站得住腳:汽車上用的也是鉛酸電池,他特別補(bǔ)充:“真正的污染源不是電動(dòng)車,而是汽車?!比绻F(xiàn)有的交通運(yùn)營者們和制造商們想與電動(dòng)車競爭,就要為大眾提供效率更高,價(jià)格更便宜,更清潔的交通工具。但問題是,與其它競爭者相比,電動(dòng)車廠商微不足道,特別是汽車產(chǎn)業(yè),吸引了數(shù)十億美元的外國投資。在中國官方制定的五年計(jì)劃中,汽車生產(chǎn)已經(jīng)被列為“支柱產(chǎn)業(yè)”。
盡管面臨著嚴(yán)酷的生存挑戰(zhàn),但電動(dòng)自行車廠商們并沒有退卻,而是知難而進(jìn),并取得了驚人成功。綠源電動(dòng)車公司的董事長倪捷是代表電動(dòng)車產(chǎn)業(yè)界的靈魂人物,他從一家小企業(yè)開始艱苦創(chuàng)業(yè),以務(wù)實(shí)的態(tài)度開拓市場,并取得成規(guī)模的研究開發(fā)成果,對中國電動(dòng)車的技術(shù)發(fā)展有獨(dú)到的見解?! ?
綠源電動(dòng)公司一開始是從政府風(fēng)險(xiǎn)投資中分離出來的。九年前,綠源現(xiàn)任總經(jīng)理胡繼紅(倪捷的妻子)制造出第一臺樣機(jī),綠源公司成立了,隨后在倪捷和胡繼紅的領(lǐng)導(dǎo)下,公司改為私營,并且從最初的投資者手里買下了所有產(chǎn)權(quán)。公司成長迅猛,去年業(yè)績傲人,電動(dòng)自行車和踏板電動(dòng)車銷量達(dá)到了12萬輛,今年的銷售目標(biāo)是30萬輛。
去尋找綠源,要從上海市一路南下,來到金華。這是浙江省的一座城市,人口百萬,工業(yè)重鎮(zhèn)。順著金華市工業(yè)園的公路就可以找到綠源公司的總部。倪捷的辦公室坐落在辦公樓的一角,寬敞舒適,是公司里為數(shù)不多的帶暖氣的房間之一,寒冷的二月里,這一點(diǎn)顯得尤為突出。倪捷煙不離手,喝著泡著濃濃的綠茶的廣口杯,侃侃道來創(chuàng)業(yè)的艱辛與收獲。他說,在中國的大多數(shù)城市里,交通是個(gè)首要問題,電動(dòng)車是昂貴的轎車和擁擠的公交車的首選替代品和補(bǔ)充品。“如果政府沒有明確的解決方案,人民就可以按自己的辦法去行動(dòng),沒有理由去阻止人們這樣做?!蹦呓莘浅?粗腥嗣竦牧α?,這一點(diǎn)在福州事件中得到了充分印證。2003年夏天,當(dāng)時(shí),綠源最大市場之一是毗鄰的福建省省會福州市,但是該市的政府卻要明令封殺電動(dòng)車,不但不給電動(dòng)車執(zhí)照,而且禁止銷售,他們沒收了綠源專賣店里的20輛電動(dòng)自行車。倪捷就聯(lián)合了126家電動(dòng)車廠家,將市政府(工商局)告上了法庭。此次,廠商聯(lián)手,迫使市政府無條件發(fā)還了無理沒收的電動(dòng)車。這次聯(lián)手取得了局部的成功。
倪捷認(rèn)為此次福州事件更深遠(yuǎn)的意義在于贏得了全國媒體的廣泛關(guān)注和支持,并且也給其它(反對電動(dòng)車的)地方政府有一點(diǎn)警示作用?!拔覀兿蚱渌胤秸畟鬟_(dá)的信息是,如果他們學(xué)習(xí)福州市政府的做法來反對電動(dòng)車,他們就會有一些麻煩?!?
圍繞電動(dòng)車引發(fā)的沖突并不只局限于地方政府和生產(chǎn)廠家,中國自行車協(xié)會也和一些廠商(包括綠源)在產(chǎn)品細(xì)節(jié)上發(fā)生分歧,諸如何種兩輪車才可以上路等。自行車協(xié)會強(qiáng)調(diào)的是電動(dòng)自行車的國家標(biāo)準(zhǔn),如重量不能超過40公斤,腳踏之間的寬度不能超過220毫米,最高時(shí)速小于20公里等等,許多最新的電動(dòng)自行車和踏板電動(dòng)車都不符合這些指標(biāo)。
例如,很多踏板電動(dòng)車配置了騎行功能不好的腳踏,并有限制速度的附加裝置。有些人買回去就可以自己把限速裝置拆掉。綠源公司的一款最新產(chǎn)品已經(jīng)不再被現(xiàn)有的電動(dòng)自行車標(biāo)準(zhǔn)所限制,綠源把這種新車型被稱做LEV,輕型電動(dòng)車的縮寫。倪捷公開承認(rèn)它已經(jīng)不僅僅是“自行車”了。在綠源的網(wǎng)站上它被稱為“電動(dòng)摩托車”:車重95公斤,配備48伏20安時(shí)的電池,電機(jī)的輸出功率高了一倍,達(dá)到500瓦,用CPU控制的電機(jī)可以將時(shí)速提高到35公里。
雖然目前國家還沒有出臺LEV統(tǒng)一標(biāo)準(zhǔn),不過在金華,即使是銷售淡季,顧客還是首選LEV。在不到一個(gè)小時(shí)內(nèi),一位25歲的年輕人和一位上班族母親相繼開走了兩輛。在被問及選中這輛車的理由時(shí),她指著城市上空的空氣污染解釋道她必須送塊頭大的兒子去上學(xué),但是為了降低本地城市的空氣污染,她寧可選擇電動(dòng)車,而不要燃油的踏板摩托車。
倪捷樂觀地相信,政府在看到LEV的普遍使用之后,會給予正式許可的?,F(xiàn)在不少人對該車重量增加是否會降低安全系數(shù)持懷疑態(tài)度。倪捷解釋道:LEV裝有電鼓閘,它的剎車效果比各種各樣電動(dòng)車常用的懸臂閘要好得多。新的能量回收型制動(dòng)系統(tǒng)也已開始使用,這種新系統(tǒng)在剎車時(shí)將把主動(dòng)的電動(dòng)機(jī)變成被動(dòng)的發(fā)電機(jī),一方面有利于迅速制動(dòng),另一方面也可以把剎車要消耗的能量提取出來對電池充電,從而擴(kuò)大了車輛的行車?yán)锍獭?
作為一名企業(yè)家,倪捷把在電動(dòng)自行車和LEV上的成功看成是走向“更大和更好”的電動(dòng)化交通工具的關(guān)鍵一步。他已經(jīng)開始關(guān)注小型電動(dòng)運(yùn)輸車輛的市場,甚至夢想有一天,綠源能夠生產(chǎn)出自己的小型電動(dòng)汽車,與大公司競爭。“他們總是在說,‘我們正在投入大量資金,我們將有計(jì)劃地把燃油系統(tǒng)改成電動(dòng)系統(tǒng)?!蹦呓葜赋?,“但是,這些大公司他們真的愿意毀掉現(xiàn)有的工廠去建設(shè)新的工廠嗎?”依倪捷看來,一批富有進(jìn)取心的小企業(yè),就像綠源這樣的,更有可能推動(dòng)電動(dòng)車革命,因?yàn)檫@樣做他們一無所失。
電動(dòng)車廠家所面臨的最大挑戰(zhàn),還不是部分地方政府的禁行令,保守的標(biāo)準(zhǔn),甚至連技術(shù)也不是主要問題,最大困擾來自道路狀況。中國正遵循著西方發(fā)達(dá)國家的發(fā)展模式,圍繞著汽車來徹底重新規(guī)劃城市。中國的每一個(gè)城市都在摒棄機(jī)動(dòng)車非機(jī)動(dòng)車混合行使模式,實(shí)現(xiàn)嚴(yán)格的分道行使模式,農(nóng)田改造成了工業(yè)園。住房從城市中心也逐漸向郊區(qū)遷徙以便讓位給亮麗的寫字樓,幾十年前西方國家就是這么干的。汽車成了這個(gè)模式中的國王。由于公共交通網(wǎng)很不健全,轎車成了從遠(yuǎn)郊區(qū)居住地到辦公室或工業(yè)園的唯一工具。
為了給更多的汽車讓路,中國的許多城市都將主路拓寬,并修建了高速公路。就像在世界其他地方發(fā)生的一樣,其后果只能是導(dǎo)致了汽車數(shù)量迅猛增長,新增的轎車馬上占據(jù)了新修的馬路。這種惡性循環(huán)在首都北京表現(xiàn)得十分明顯。1997年,北京只有1百萬輛轎車,有人曾經(jīng)預(yù)計(jì)到2008年才達(dá)到2百萬輛。但事實(shí)是,去年已經(jīng)突破了2百萬輛,新的預(yù)測是2008年將達(dá)到350萬輛。北京大學(xué)城市規(guī)劃專家俞孔堅(jiān)尖銳地指出:“舉國上下,大家都認(rèn)為馬路越寬交通狀況就越好,但是他們是錯(cuò)的?!?
汽車文明的興起對自行車是一個(gè)災(zāi)難,馬路拓寬的代價(jià)是占用自行車道,高速公路不許自行車上道,而且?guī)缀醪豢纱┰?。窄一點(diǎn)的馬路上,高峰時(shí)間的車流阻斷了自行車道和交叉路口,引起騎車人的強(qiáng)烈不滿。俞教授以前騎自行車從家到學(xué)校只需要20到30分鐘,但他現(xiàn)在開車,依據(jù)交通狀況,花費(fèi)10到60分鐘不等?!膀T自行車太危險(xiǎn)了,所以許多人不騎車了,我也不騎了?!?
不過俞教授相信從長遠(yuǎn)來看,燃油的車輛終將會被迫給電動(dòng)車讓路。一方面的原因是交通堵塞,另一方面的原因是中國的城市污染。在金華,即使污染不那么嚴(yán)重的日子,城市的天際線也都消失在煙塵之中,越來越多的大氣污染物是從機(jī)動(dòng)車排氣管中排出的。
何院士之所以對電動(dòng)車充滿信心,主要因?yàn)橹袊鵀槭退冻龅膽?zhàn)略代價(jià)太高。中國石油進(jìn)口增加速度和它的汽車數(shù)量增加速度并駕齊驅(qū)。中國已經(jīng)超過了日本成為世界第二大原油進(jìn)口國,開始與美國競爭世界上最大的石油消費(fèi)國。為減少對進(jìn)口原油的依賴,也為減輕沉重的環(huán)保負(fù)擔(dān)著想,中國已經(jīng)制定了比美國更嚴(yán)格的燃料效能標(biāo)準(zhǔn),同時(shí)正在考慮對零售汽油和柴油加征20%到50%的燃油附加稅。
如果中國能找到一種解決辦法,能使得相對高效的電動(dòng)車在交通系統(tǒng)中發(fā)揮更顯著的作用,這將為世界上其它發(fā)展中國家乃至發(fā)達(dá)國家樹立一個(gè)的典范。這也包括了全世界中最依賴汽車的國家——美國。在日本和歐洲,自行車、火車和其它形式的公共交通工具還在積極地運(yùn)轉(zhuǎn),而美國是極少數(shù)絕大部分交通完全依賴汽車的國家之一,引用WaveCrest公司本杰明先生的話:“我們住在大泡沫里?!?
IN REJECTING ELECTRIC BIKES, the municipalities cited such concerns as the threat of pollution from spent lead-acid batteries, interference with automobiles resulting in accidents or slowed traffic, and the impact on the viability of public transit systems. Advocates for green transportation say these arguments amount to thinly veiled attempts to protect the electric-bicycle industry's competitors. "The real reason is competition from interest groups," says He Zuoxiu, a renowned theoretical physicist and academician at the Chinese Academy of Sciences.
An outspoken figure in public debates around environmental and energy policy, He says none of the arguments against electric bikes has merit. Lead-acid batteries, he points out, are used in cars, too. "The real pollution source is not the electric bikes, it's the automobiles," he adds. And he says transit operators and manufacturers should be forced to compete with the electric bikes by offering more efficient services and cheaper, cleaner vehicles. The problem, he explains, is that electric-bike manufacturers are insignificant next to the other interest groups, particularly the car makers that are attracting billions of dollars of foreign investment. The automotive industry is identified as a "pillar industry" in China's official five-year plans.
Back with surpri Although the odds against them are daunting, electric-bike manufacturers are pushing sing success. The mastermind of one of the most high-profile battles is Ni Jie, president of Luyuan Electric Vehicle Co., a privately owned manufacturer that has a pragmatic approach to the market, a sizable R&D effort, and an ambitious vision for Chinese EV technology.
Luyuan EV was a government venture-capital spinoff. Building from a prototype put together nine years ago by Luyuan's general manager, Hu Ji Hong, Ni's wife, Luyuan went private after Ni, Hu, and other principals bought out the initial investors. They have built a dynamic company that sold 120 000 electric bikes and scooters last year and expects to sell 300 000 this year [see photo, "Coming Off the Line"].
To find Luyuan EV, you must head off the beaten track to Jinhua, an industrial metropolis of 1 million people that is tucked into the unbroken sprawl south of Shanghai that is Zhejiang province. In the chairman's spacious corner office (one of the few heated rooms at Luyuan on a cold February day), Ni chain-smokes, sipping from a seemingly bottomless jar of well-steeped green tea. He says traffic is the top concern in many Chinese cities, and the electric bicycle fills a void by offering an affordable alternative to sitting in a stationary car or bus. "If governments don't have the solution, the people will behave in their own ways," says Ni. "There's no way to stop that."!
Ni took people power to surprising limits in 2003 when officials in Fuzhou, the capital of neighboring Fujian province, decided to ban electric bicycles—shutting off what until then had been one of Luyuan's best markets. The city not only ceased issuing licenses for electric bicycles but also seized 20 electric bikes from a bicycle shop in the summer of 2003. Ni gathered a coalition of 126 electric-bike manufacturers and filed suit against the city in its own municipal court. The coalition scored a partial win against the city government, forcing it to return the seized bikes.
Far more valuable, says Ni, was the sympathetic coverage they received from national media and the warning that attention sent to other municipalities. "What we told other governments is that if they do the same as Fuzhou, there will be some trouble," he says.
Conflict over electric bikes isn't limited to the municipalities and the manufacturers. Even the China Bicycle Association has been clashing with some companies, including Luyuan, over what types of electric two-wheelers should be on the road [see photo, "The Basic Bike"]. The bike group enforces a national standard for electric bicycles, and whichever parameter you choose—weight (no more than 40 kilograms), width (220 millimeters for the pedal shaft), speed (20 km/h, maximum)—many of the latest electric scooters either flunk or thwart the standard.
Lots of electric scooters, for example, are outfitted with nonfunctioning pedals and with speed-limiting devices designed for easy removal after purchase. Luyuan's latest machine doesn't just skirt the electric-bike standard; it rumbles right over it. Luyuan calls its new product the LEV, short for light electric vehicle, and Ni openly admits that it's more than a bicycle. Luyuan's Web site calls it an electric motorcycle, and that seems fitting: the LEV weighs in at 95 kg; its 48-V, 20-AH battery packs double the energy of the standard bike; and its 500-watt CPU-controlled motor propels it to 35 km/h.
The LEV has no official status in China. Nevertheless, on what should be a slow sales day at a Luyuan retail outlet in downtown Jinhua, the LEVs are flying out the door. In the space of an hour, one is snapped up by a 25-year-old man, and a working mother rolls out with another. Why did she choose an LEV? She drives her rather big-boned son to school and prefers an LEV to a gas-powered scooter, pointing to the endemic air pollution hanging over the city.
Ni is betting that governments will sanction the LEV if it proves popular. He says he believes that Luyuan has addressed the one concern municipalities could level against the LEV that might have stuck: reduced safety due to the cycle's greater weight. The LEV employs an electric drum brake that, Ni claims, stops it faster than the cantilever brakes used on garden-variety electric bikes could. A is also in the works that would boost braking power by using the in-hub motor as a generator to pull energy out of the wheels, extending the vehicle's range by simultaneously charging the battery.
Ever the entrepreneur, Ni sees the success of the LEV as a step toward bigger and better things. He already has his eye on the market for small delivery vehicles, and he even imagines Luyuan making electric cars and challenging the major automakers. "They are investing money, saying we are going to change the gasoline system to electric," he points out. "But will the big companies really be willing to destroy their own factories to build the new ones?" In Ni's view, small, aggressive Chinese companies like Luyuan are more likely to drive the EV revolution, because they have nothing to lose.
THE BIGGEST CHALLENGE facing electric-bike makers may not be municipal bans, conservative standards, or even technology. It may be the roads. China is following the development path of Western countries like a map, rapidly redesigning its cities around the automobile. Across China, cities are rejecting a mixed-use model and redeveloping along a strict zoning model, razing residential buildings in center cities to make way for shiny office towers and paving farmland on the periphery to create large industrial parks. Displaced from the urban centers, houses and other residential buildings are springing up in sprawling suburbs, just as they did in the West decades ago. The automobile is king in this model, because in the absence of extensive public transit, cars are the only way to get from distant suburbs to offices and industry parks.
To make way for more cars, China's cities are widening their main roads and building highways. The result has been a rapid increase in automobile use that, just as it does everywhere else in the world, almost instantly absorbs the extra roadways. The resulting gridlock has been especially acute in China's capital. Beijing had 1 million cars in 1997 and was once expected to reach 2 million in 2008. Instead, it hit 2 million last year and now expects 3.5 million to be in use in 2008. "All over the country, they believe that wider roads are more efficient for traffic. They're wrong," says Yu Kon gjian, an urban planning expert at Beijing University.
Car culture is a disaster for the bicycle. Road widening often comes at the expense of bike lanes, while highways are off-limits to bikes and nearly impossible to cross. On the smaller roadways, rush-hour traffic blocks the bike lanes and intersections, prompting outbursts of road rage from frustrated cyclists. Yu used to cycle 20 to 30 minutes between work and home, but he now drives—a 10- to 60-minute trip, depending on the traffic. "It's too dangerous to bike, so people give up. I gave up," he says.5 b3 B!
Yu is confident that, in the long run, it is the gas guzzlers that will be forced to give way. One reason is gridlock. Another is China's endemic urban pollution [see photo, "Pea Soup"]. On all but the best days in Jinhua, for example, the city skyline disappears behind a dense haze of smog and particulates; more and more of that atmospheric soup is pouring out of tailpipes.
It's the strategic cost of petroleum that inspires professor He's confidence in the electric bike. China's oil imports are on the same exponential growth path as its car fleet. China has eclipsed Japan as the second-biggest importer of oil, bringing it into direct competition with the world's leading consumer of petroleum: the United States. With import dependence and environmental burdens in mind, China has promulgated fuel-efficiency standards that are stricter in principle than those currently in force in the United States, and it is considering imposition of a 20 to 50 percent national tax on retail gasoline and diesel.
IF CHINA CAN FIND A WAY to make relatively efficient electric bikes a significant part of its transportation system, it could have major repercussions elsewhere in the developing—and developed—world. That includes the United States, which has the world's most car-dependent culture. Unlike Japan and Europe, where bicycles, trains, and other forms of transportation still thrive, the United States is one of the few places where people move almost exclusively by car. As WaveCrest's Benjamin puts it, "We live in a bubble."
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