To separate and supply paper one by one in a good condition at all times irrespective of changes of temperature by constituting a seat of a member for energizing retard roller pressure or a member for energizing separation roller pressure in such a manner that the height of a seat face is changed by temperature.

If a seat member 7 is constituted by a member which depends on temperature greatly, it is shrunk by temperature, and a bottom face 7a moves. That is, the height of a seat face of a spring 6 moves. Consequently, it is possible to adjust energizing force for a retard roller shaft 2a of the spring 6. The seat member 7 is inflated more when temperature is high, and the bottom face 7a moves downward, that is, the height of the seat face of the spring 6 is reduced. Accordingly, energizing force of the spring 6 is reduced. An increase of friction resistance between papers is offset by this. On the contrary, the seat member 7 is shrunk due to the reduction of temperature, the height of the seat face is increased, and energizing force of the spring 6 is increased. The reduction of friction resistance of a material is made up for by this.