作者: alpha (要轉換跑道~~)
標題: [轉錄]翻譯文章--四行程與二行程化油器的差別(修正版)
時間: Fri Mar 25 21:43:38 2005

※ 本文轉錄自 [NSR] 看板

作者: Bike (徵小引擎) 站內: NSR
標題: 翻譯文章--四行程與二行程化油器的差別(修正版)
時間: Mon Mar 21 19:45:12 2005

資料來源:http://www.eric-gorr.com
翻譯原則:為了行文順暢、名詞差異,以及自身的語言能力,所以我沒有逐字逐句
          的英翻中。在一些我沒有把握的地方會附上原文或者附註

2005/3/21修改,感謝 GD6150 提供的資料讓我修正~~~

    二行程與四行程化油器的差別主要在於吸入燃油的速度(intake velocity)。
因為二行程引擎的吸入速度比較低,所以將主油嘴座設計成半月造型(註一),
藉此增加文式管的壓力差,增進吸取燃油的能力。相反的,四行程引擎的燃油在
進氣口會遭受剪力(shear) (註二),使得燃油從與空氣的混合能力降低,因此四
行程化油器的設計重點,反而是著重燃油混合氣霧化的能力。另一方面,四行程
化油器的油嘴比較多、調整螺絲的調整能力較佳,通常也會設計一個加速幫浦。
Kehin CR是四行程化油器的經典代表作。
    早期二行程化油器的製造商利用油嘴的大小來彌補油門中度開啟時油氣不足
的缺點,卻也同時降低(註三)全油門時的燃油供應效率。因此,二行程化油器的
設計新趨勢是藉由一個輔助幫浦,在油門開度1/4~3/4時將燃油噴入文式管中,
彌補油氣不足的缺點。這個輔助幫浦由發電機供應約略5W的電力,並搭配油門滑
塊感應器及轉速感應器,藉由油門開度與引擎轉速這兩個參數來控制幫浦作動。

註一:原文為 ”…needle jet has a half-moon shaped hood protruding into the
      venturi to produce a low pressure area that aids in drawing the fuel up
      through the needle jet.”needle jet 是與主油嘴鎖固的元件,有的 needle jet
      與 main jet 為分離設計,有的則是直接做在化油器本體上。原文說 needle jet
      的半月設計,使得文試管中的氣流因為半月外型的落差而產生更多的壓降
註二:原文為 ”… so much of the fuel shears along the intake port and
      separates from the mixture stream.” 因此我用力學名詞”剪力”
      (shear force)來翻譯,我猜測可能跟文中一開始提到的intake velocity
      有關,可能是四行程引擎的 intake velocity 比二行程引擎大,雖然文式
      管的壓差大,也同時使得燃油與空氣的霧化混合能力降低。
註三:原文是用compromised,有妥協的意思,因此我用翻譯成”降低效率”

原文
          The Differences in Two-Stroke and Four-Stroke Carbs
  The difference between a two-stroke and four-stroke engine is intake
velocity. Two-stroke engines have lower velocity so the needle jet has
a half-moon shaped hood protruding into the venturi to produce a low
pressure area that aids in drawing the fuel up through the needle jet.
Four-stroke carbs need to atomize the fuel more so than a two-stroke carb
because so much of the fuel shears along the intake port and separates
from the mixture stream. Four-stroke carbs have more jets and finer
adjustment screws, plus they usually are equipped with an accelerator pump.
A typical state of the art four-stroke carb is the Kehin CR.
  The latest trend in two-stroke carbs features a pump that sprays fuel into
the venturi from 1/4th to 3/4th throttles. In the past, carb manufacturers
made jet needles that attempted to compensate for the natural lean condition
of the mid-range but that compromised the jetting at full throttle.
The auxiliary pumps are powered by electricity supplied by the alternator
(about 5 watts) and controlled by either a throttle position or an rpm sensor.

最後附上 GD6150 提供的化油器各部油嘴中英名詞對照
main jet 高速油嘴
slow jet/idle jet/pilot jet 怠速油嘴
throttle valve/throttle slide 節流閥or柱塞
jet needle/tapered needle 油針
needle jet/atomiser 個人習慣稱作主油嘴座

以上參考看看嘍~~~有錯請更正~~~
--
原先的那篇請板主D掉吧~~~

--
  Origin:  玩車人的天地 ˙東吳機研站  scumotor.com.tw 
  Author: Bike bike1.ess.nthu.edu.tw 發表advance :要知道fcc 日製的價 私底下來信....^^我可以拿到^^        05/03/22
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