wall of the bill tray 11 a holder 14 secured detachably by the holder latch 13 a cushion plate 15 retained by the holder 14 and a steel ball 16 the holder 14 has formed therein a cushion chamber 17 in which the cushion plate 15 and the steel ball 16 are disposed the cushion plate 17 produces elastic pressure urging the steel ball 16 into constant engagement with the bill tray 11 thereby allowing as indicated by p in fig8 b a bill to be held between the bill tray 11 and the steel ball 16 tightly the upper wall 6 has the pen holder 4 formed behind the bill holder 8 the pen holder 4 is defined by a protrusion 18 extending in a width wise direction of the upper wall 6 in parallel to the rear wall of the bill holder 8 the bearing assembly 9 includes as clearly shown in fig4 to 6 a front display mount protrusion 20 a rear display mount protrusion 21 and right and left bearings 24 the display mount protrusions 20 and 21 extend in the width wise direction of the upper casing 3 the bearings 24 are disposed between the display mount protrusions 20 and 21 the display mount 10 includes a font slant wall 25 and a rear slant wall 26 rectangular walls 27 as clearly shown in fig4 and 6 are formed on both sides of the front slant wall 25 the rectangular walls 27 have formed therein stay guide slots 28 the display 30 is as shown in fig1 and 2 pivotably 10 supported by the bearing assembly 9.