PURPOSE: To provide the subject compact-sized apparatus consisting of a specific construction to enable the loosening of unloosened leaf raw material with a rotary rake and capable of effectively loosening unloosened leaf while preventing the generation of fine pieces.

CONSTITUTION: Unloosened leaf raw material is charged into a feeding path 9 from a charging port 8 opened at the top of a vertical cylindrical casing 7. The raw material is loosened by contacting both faces of the leaf raw material with rotating 1st-stage rotary rakes 11a, 11b having loosening rods protruded from the outer circumference. When the loosening of both side parts is detected by plural sensors pH1 to pH5 arranged in the moving direction of the 1st-stage rotary rakes 11a, 11b, the rakes are moved to the middle part of the raw material by the command transmitted from a controller to effect further loosening of the raw material. Finally, after the complete loosening of the raw material lump, the loosened raw material is further finely loosened by the 2nd-stage rotary rakes 11c to 11g placed under the 1st-stage rotary rakes 11a, 11b and having plural loosening rods on the outer circumference.