Patent ID: 8162244
Filing Date: 2012-04-24
Classification: B02C,G01B

Abstract:
1. A shredding machine for shredding sheet material, the machine comprising a feed aperture and a cutting mechanism powered by an electric motor, the feed aperture being arranged to receive sheets for shredding and to direct such sheets to the cutting mechanism for shredding, the machine having means for measuring the thickness of sheet material passed into said feed aperture for shredding which sheet material may comprise a plurality of superimposed sheets which together provide such thickness, said measuring means controlling said cutting mechanism so as to permit energisation of the cutting mechanism where the thickness of sheet material measured thereby is below a controlling threshold and to prevent such energisation where the thickness of sheet material measured is above said controlling threshold, characterised in that the machine includes at least one sensor sensing a variable supply voltage and control means operable to adjust said controlling threshold automatically in dependence upon the value of the supply voltage sensed.