Patent ID: 8219240

Claim:
A conveyance device comprising: a motor; a conveyance unit that conveys an object to be conveyed by a force generated by the motor; a movement detection signal output unit that outputs a movement detection signal each time it is detected that the object to be conveyed has moved a predetermined distance by conveyance operation of the conveyance unit; a storage unit that stores a parameter value TX concerning a cycle of the movement detection signal outputted from the movement detection signal output unit; a time measurement unit that measures elapsed time from when the time measurement unit has been reset; a first updating unit that updates the parameter value TX stored in the storage unit to the elapsed time measured by the time measurement unit and resets the time measurement unit each time the movement detection signal is outputted from the movement detection signal output unit; a standby time setting unit that sets a value larger than the parameter value TX stored in the storage unit as a standby time TW; a second updating unit that updates the parameter value TX stored in the storage unit to the standby time TW each time the elapsed time measured by the time measurement unit reaches the standby time TW; a manipulated variable determination unit that periodically determines a manipulated variable to the motor based on the parameter value TX stored in the storage unit; and a motor driving unit that inputs to the motor a driving signal for driving the motor corresponding to the manipulated variable determined by the manipulated variable determination unit, wherein the standby time setting unit sets to the standby time TW a value of a specified monotonically increasing function f(TX), which has the parameter value TX as an input variable, and the monotonically increasing function f(TX) satisfies a condition f(TX)>TX.