Patent ID: 7270469

Claim:
Apparatus for adding pigmentation material to a concrete mixture, comprising: a hopper for containing the pigmentation material and having a bottom wall; a lower horizontal rotor with flighting positioned adjacent the bottom wall of the hopper and having opposite first and second ends; an upper horizontal rotor with flighting positioned in the hopper above the lower rotor; an outlet opening adjacent the first end of the lower rotor; a cleanout opening adjacent the second end of the lower rotor, the cleanout opening being normally closed to prevent pigmentation material from exiting through the cleanout opening; a drive system to rotate the upper and lower rotors; the drive system being adapted to rotate the lower rotor in opposite first and second directions for moving the pigmentation material towards the outlet and cleanout openings, respectively; a conveyor below the outlet opening for carrying the concrete mixture and receiving the pigmentation material discharged through the outlet opening; the conveyor having a discharge end; a concrete mixer adjacent the discharge end of the conveyor for receiving the concrete mixture and pigmentation material from the conveyor and for mixing the concrete mixture and pigmentation material together.