In a rice huller, a first small-diameter pulley and a second large-diameter pulley are attached to a first roll shaft. The cable length detection apparatus has a signal compressing circuit, a signal converting circuit and a length calculating circuit. An electronic switch connects the juncture of the inductor and the diode to both the other terminal of the stack and the battery. A second sensor cluster comprises a second plurality of bearing measuring sensors. The heating rod includes a first portion inserted in the hole and coupled to the arm, and a second portion protruding from the bottom surface. A controller stops an operation of the master and controls the switch such that the clock signal output from the oscillation generator is supplied to the slave, upon transition to a power saving mode.