辘轳是古代汲水用的工具,广泛应用于农业灌溉。在井上固定木架,中间穿过一根横轴,轴上安装绞轮并缠绕绳索,绳索一端拴住水桶垂于井下盛水,一端为固定手摇柄。取水时,转动绞轮上手柄,将水提上来。辘轳是利用轮轴原理做功的机械,最早见于汉代(公元前202年~公元9年)。辘轳出现后,深井取水问题得以解决,逐渐成为使用最为普遍的提水机械。
Windlass is an ancient pumping tool, widely used in agriculture irrigation. A wooden bracket is fixed over a well, and a horizontal axle goes through in the middle of the bracket. Twisted wheels are equipped on the axle to wound ropes. One end of the rope is hitched with a bucket to hang in the well to contain water, and the other end is the fixed handle. In watering, it is needed to rotate the handle, and leverage the bucket. Windlass is a kind of machinery based on the axle principle.
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