protrusions 34 are formed at equal angles apart in the end edge around the axis of the roller 30 the quantity of which is equal to that of the grooves 33 as viewed from the end face of the roller as shown in fig2 and fig5 the protrusions 34 and the grooves 33 are arranged in alternation furthermore the outer sides of the protrusions 34 farther from its axial center are gradually diminished in shape the pawl 40 having a shaft 41 a pivot hole 41 through the shaft 41 and a pressing member 43 extending from the outer portion of the shaft 41 with the portion at the outer edge of the pressing member 43 being of a pointed profile the pawl 40 by means of the pivot hole 42 entrances at its two ends is respectively sleeved onto posts 121 and 181 as shown in fig4 at the interior surface of the main portion 12 of the main member 11 and the main portion 18 of the secondary member 17 and is capable of revolving towards the upper extent of the roller 30 adjacent to the front end of the dispensing body 10 the pressing member 43 is postured vertically downward and furthermore its bottom edge against the circumferential face of the roller 30 in addition the pawl 40 has a triangle shaped engaging portion 45 extending downward from its inner end and based.