Sieving

Claim 5

Sieving apparatus comprising means whereby fluent material to be sieved is supplied through an inlet port into chamber means,a sieve in said chamber means, two discharge ports for said chamber means, means defining a first passage connected to one outlet port for conveying from the chamber means through material that has passed through the sieve and means defining a second passage connected to the other outlet port for conveying from the chamber means overtail material that has not passed through the sieve, means for forcing air through the sieve co-currently with material to increase the rate of material flow through the sieve, and means for preventing said forced air from escaping at said passages with either the through material or the overtail material.

Claim 6

Sieving apparatus comprising means whereby fluent material to be sieved is supplied through an inlet port into chamber means,a sieve in said chamber means, two discharge ports for said chamber means, means defining a first passage connected to one outlet port for conveying from the chamber means through material that has passed through the sieve and means defining a second passage connected to the other outlet port for conveying from the chamber means overtail material that has not passed through the sieve, means for forcing air through the sieve co-currently with material to increase the rate of material flow through the sieve, and means for preventing said forced air from escaping at said passages with either the through material or the overtail material.

Claim 7

Sieving apparatus according to claim 2, wherein said chamber means comprises upper and lower walls defining a chamber, said sieve extending over part of the horizontal cross-section of said chamber at a position intermediate said upper and lower walls of the chamber, wall means separating that part of the chamber below said sieve from the remainder of the chamber, said inlet port being in the upper wall of the chamber means and said outlet ports being in the lower wall of said chamber.

Claim 8

Apparatus according to claim 3, wherein each said passage defining means incorporates flexible sleeve coupling means.

Claim 9

Apparatus according to claim 2, said means for forcing air through the sieve including means for exhausting air from said first passage communicating with the discharge outlet port adapted to pass the material that has passed through the sieve.

Claim 10

Apparatus according to claim 5, wherein said first passage contains a rotary air lock for preventing escape of the forced air, and said air exhaust means is connected to the first passage between the air lock and the associated discharge outlet port.

Claim 11

Apparatus as defined in claim 2, wherein means defining a passage is connected to said inlet port and rotary air locks are provided in all of said passages.