caused to separate from or contact lightly or strongly with a feed roller of a printing paper feed device when the switching member is rotated resulting in the required paper tension application_number US 61821384 A description fig1 is a perspective view showing an outer appearance of a main part of the invention inner mechanisms of a printer are protected by a machine frame not shown this machine frame rotatably supports a rotation shaft 1 with a rotation arm 2 at one end and further rotatably supports a switching member 3 via an operating member 8 which is formed with a group of engaging notches 8a 8b 8c at its a lower part the switching member 3 is provided with a connecting link 4 connected to an end of the rotation arm 2 the link 4 has an oblong hole 5 at one end which serves to connect the connecting link 4 to the arm 2 actuation of the rotation arm 2 by rotation of the switching member 3 will be mentioned later in connection with fig2 to 4 a rotation stopping fixture 6 comprising a spring member which temporally and angularly stops rotation of the member 8 due to said notches 8a 8b 8c engaging with a corresponding mountain like member 7 which is formed at an end.