Patent ID: 7128483
Filing Date: 2006-10-31
Classification: B41J

Abstract:
1. A ribbon cassette, comprising: a ribbon supply spool; a ribbon take up spool that takes up an ink ribbon from said ribbon supply spool by rotating in a first rotation direction, said ribbon take up spool being provided with an engaging portion; and an engaging member disposed on the ribbon take-up spool that resiliently engages with said engaging portion to prevent said ribbon take up spool from rotating in a second rotation direction opposite to said first rotation direction, said engaging member coming off from said engaging portion when said ribbon take up spool rotates in said first direction, wherein said engaging portion includes a first and second walls, said take-up spool being prevented from rotating in said second direction as said engaging member engages with the first wall, and said take-up spool being allowed to rotate in said first direction as said engaging member slips on the second wall.