Patent ID: 8672247

Claim:
A shredder comprising: a housing having a throat open to an exterior of the housing for permitting a user to feed at least one article to be shredded; a shredder mechanism received in the housing and including an electrically powered motor and cutter elements, the shredder mechanism enabling the at least one article fed into the throat to be shredded to be fed into the cutter elements and the motor being operable to drive the cutter elements in a shredding direction so that the cutter elements shred the articles fed therein; a thickness detector configured to detect a thickness of the at least one article to be shredded being received by the throat, said thickness detector comprising a contact member movable by the at least one article being inserted into the throat; a controller configured to prevent the motor from driving the cutter elements in the shredding direction responsive to the detector detecting that the thickness of the at least one article is at least equal to the predetermined maximum thickness; wherein said thickness detector is a variable thickness detector for outputting a variable amount of movement of said contact member; wherein said thickness detector comprises a sensor and a detectable part movable for detection by the sensor, and wherein said thickness detector is configured such that movement of said contact member amplifies movement of the detectable part at the sensor.