on a location corresponding to the pickup roller 10 and spaced from the pickup roller 10 at a selected distance to couple with the pickup roller 10 to catch papers 200 of different thickness there is also an auxiliary intermediate roller 21 installed on a location corresponding to the intermediate roller 20 and spaced from the intermediate roller 20 at a selected distance to couple with the intermediate roller 20 to catch papers 200 of different thickness there is further an auxiliary delivery roller 31 installed on a location corresponding to the delivery roller 30 and spaced from the delivery roller 30 at a selected distance to couple with the delivery roller 30 to catch papers 200 of different thickness similarly there is an auxiliary discharge roller 81 installed on a location corresponding to the discharge roller 80 and spaced from the discharge roller 80 at a selected distance to couple with the discharge roller 80 to catch papers 200 of different thickness the driving motor 70 provides the driving power required for the operation of the entire mechanism it drives a first driving gear 71 a second driving gear 72 and a third driving gear 73 while three driving gears are indicated in the drawings it is by no means the limit of the driving gear number that can be used to transmit the driving power to other elements the first clutch is coupled to the driving motor 70 via the gears and is located on the media conveying path to control the operation of the pickup roller 10 the first clutch consists of a first clutch lever 40 a first clutch gear 41 and a first clutch idle gear 42 the first clutch lever 40 is.