Sonic sifter

Comparative tests performed on a Ro-Tap unit, a vibrating unit (Sonic Sifter — Allen-Bradley), and the Alpine Air Jet Sieve are shown in Figs 6 and 7. Fig 6 is a powdered cement Fig 7 is cadmium stearate, a waxlike material which clogs easily. These separations were all made on a 42 micron mesh sieve. These tests showed that the Alpine Jet Sieve effected good separations in a matter of minutes compared with the much longer times required for the other systems... 

Brittle powders are best sieved using a gentle sieving action as is found, for example, with the Air Jet Sieve or the Sonic Sifter. 

A downward air flow has been found to improve sieving rate for 10, 25 and 45 pm electroformed sieves using a sonic sifter operating at 107 dB and 78 Hz [102]. The sieving rate also increased with decreasing feed rate, especially for sub-10 pm sieves [103]. 

FIGURE 28 Sonic sifter with the typical setup. 

Figure 3.11. The ATM Sonic Sifter uses a pulsating air column to assist the passage of powder down through a nest of sieves [33]. a) Appearance of the Sonic Sifter, b) A single cycle in the operation of the Sonic Sifter. (Images courtesy of, and used with the permission of ATM Corp.)...

The Sonic Sifter has been designed to combine two motions to provide a precise particle separation. A vertical oscillating column of air and a repetitive mechanical pulse is used to move the material to be sifted through a single sieve or set of sieves. The name Sonic Sifter appears to come... 

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