| 摘要 |
<p>For continuous measurement of the mass flow of threshed grain in a combine harvester by means of a signal transmitter (18) and a signal detector (20) placed on their respective sides of a passage (12) for the grain flow, use is made of a beta, gamma or X-ray radiation source as a signal transmitter. Since the attenuating effect of the grain flow on these rays practically does not depend upon other variable factors than the density of the grain flow, the output signal of the detector is an accurate expression of this density. Knowing the velocity of the grain flow and the cross sectional area of the passage, the mass flow can then be calculated with a correspondingly great accuracy.</p> |
