问题 问答题 简答题

简述齿轮泵的工作原理?

答案

参考答案:

当电机带动主动旋转时,主动轮和从动轮的一对啮合齿转到下面就开始脱开,这时两齿轮下面的齿中容积就逐渐增大,形成局部真空,因此吸入管中的油在大气压力作用下进入吸油腔、填满齿轮空间,齿轮继续旋转,将吸入的油沿齿轮圆周与泵体所形成的空间压送到上面压油腔中去。这时,主、从动齿轮的相互啮合,将上面齿谷中的油挤出来,向压油腔输出,这样就完成了吸油过程和排油过程,齿轮泵也属于容积式泵,结构简单,运转可靠,适用于不含杂质的液体。

听力题

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A.teachers

B.adults

C.children

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A.make them suitable to different readers

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C.reduce the cost of them

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C.enrich students’ knowledge about nature

D.help children to learn English

选择题