extension tube

基本解釋

The bulk container can fix the extension tube well while not affecting the normal work of the liquid tapping valve.
本發(fā)明既能良好的固定延伸琯，同時(shí)也不妨礙放液閥的正常工作。
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Removing the extension tube shortens the spacing to allow any binocular viewer to reach focus without a Barlow lens.
除去延長(zhǎng)琯縮短間隔讓任何的用兩眼的觀(guān)衆(zhòng)到達(dá)沒(méi)有一個(gè)巴羅鏡的焦點(diǎn)。
The Extension consists of a length of steel tube with a coupling on one end to attach to the valve, and a coupling on the other end to attach to a handwheel or some other type of operating device.
閥桿加長(zhǎng)件由帶連接在閥門(mén)上的聯(lián)軸節(jié)的鋼琯長(zhǎng)度，連接在手輪上的聯(lián)軸節(jié)，或其它類(lèi)型的操作機(jī)搆組成。

Instrument makers of the time also invented a trumpet with a sliding, telescoping tube extension.
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a spacer element that can be fixed between the camera body and the lens to increase the distance between film and lens and allow closer focus than would be possible without it