摘要 |
A gear pump has pairs of intermeshing gears 4, 5, 6 disposed in a housing 1. The gears of each pair are mounted on respective vertical shafts 2 and 3. An inlet path 17 leads to the gears and an outlet path 18 leads from the gears. A channel 20 provides a communication between an axial exit from the teeth of the gears of the lowermost pair on the inlet side and a tunnel 21 provides a communication between an axial exit from the teeth of the gears of the lowermost pair on the outlet side and the outlet path 18. This channel and tunnel enhance the dispersal of colourant, for example, in a surface layer of plastics material passing through the pump. |