Measurement of elliptical gear flowmeter is mainly composed of two meshing elliptical gear and shell (measurement room) composed of oval gear in the measured medium pressure difference of p=pl-p2, which make the rotation torque. 在(a)所示位置時，由于P1>P2，在P1和P2的作用下所產(chǎn)生的合力矩使輪A產(chǎn)生順時針方向轉(zhuǎn)動，把輪A和殼體間的半月形容積內(nèi)的介質(zhì)排至出口，并帶動輪B作逆時針方向轉(zhuǎn)動，這時A為主動輪，B為從動輪，在 (b)上所示為中間位置，A和B均為主動輪；而在（c）上所示位置，P1和P2作用在A輪上的合力矩為零，作用在B輪上的合力矩使B輪作逆時針方向轉(zhuǎn)動，并把已吸入半月形容積內(nèi)的介質(zhì)排至出口，這時B為主動輪，A為從動輪，與 (a)上所示情況剛好相反．如此往復(fù)循環(huán)，輪A和輪B互相交替地由一個帶動另一個轉(zhuǎn)動，將被測介質(zhì)以半月形容積為單位一次一次地由進口排至出口． Obviously, on the map (a), (b), (c) shows, only said elliptic gear turned 1/4 weeks, and the discharge of the measured medium is a half moon volume. Therefore, the elliptical gear per week to the ratio of measured medium quality for half 4 times the product description the volume flow of Q through the oval gear meter meteor: Q=4n V 0 type: n - rotation frequency of elliptical gears (Rev / sec);

The 0 part of the volume V - half moon (beckham. ).

In this way, as described in the elliptical gear flowmeter half product 0 V under certain conditions, as long as the measured elliptical gear rotation speed n, can know the measured medium flow.