Waste shredder comprising at least two rotors

1. A waste shredder ( 1 ), characterised in that it comprises at least one supporting structure ( 12 ) which carries a loading chamber ( 3 ), at least two rotors ( 4 ) placed in seats formed in the bottom wall of the loading chamber ( 3 ) and a movable hopper ( 2 ), sliding above the loading chamber ( 3 ) and provided with a reciprocating translational movement, which has two end walls (B, B′) and which carries a plurality of stiff vanes ( 5 ) placed in the spaces between said rotors ( 4 ), the end walls (B, B′) of the hopper ( 2 ) and the vanes ( 5 ) protruding downwards until they skim the bottom of the loading chamber ( 3 ) to press the material ( 8 ) to be shredded against the rotors ( 4 ), which rotate in the opposite direction to the translational movement of the hopper ( 2 ).

2. A waste shredder ( 1 ) as in claim 1 , characterised in that the waste shredder ( 1 ) comprises n rotors ( 4 ) and n−1 vanes ( 5 ), n being a whole number of two or more.

3. A waste shredder ( 1 ) as in claim 1 , characterised in that the rotors ( 4 ) reverse their direction of rotation when the hopper ( 2 ) reverses its direction of translation.

4. A waste shredder ( 1 ) as in claim 1 , characterised in that each rotor ( 4 ) is driven by a motor ( 6 ).

5. A waste shredder ( 1 ) as in claim 4 , characterised in that the motor ( 6 ) is a hydraulic motor.

6. A waste shredder ( 1 ) as in claim 4 , characterised in that each motor ( 6 ) is carried by supporting means ( 7 ) and is coupled to the shaft of one of the rotors ( 4 ) by means of fast coupling/uncoupling means.

7. A waste shredder ( 1 ) as in claim 1 , characterised in that each rotor ( 4 ) belongs, together with the counter-blades and with a supporting structure, to a shredding unit ( 11 ) that can be extracted sideways from the loading chamber ( 3 ).