Ribbon Cartridge Inlet Closing
Original Publication Date: 1985-May-01
Included in the Prior Art Database: 2005-Feb-18
Circular spring element 1, which is flexed inward, presses a typewriter ribbon 3 against an opposite wall 5 in a ribbon cartridge when ribbon 3 is slack (Fig. 1). This traps ribbon 3 and prevents slack in ribbon 3 from causing malfunctions by entering cartridge 7. During ribbon feed into cartridge 7, as shown by an arrow (Fig. 2), normal tension of ribbon 3 flexes spring 1 further inward. Spring 1 is then spaced away from wall 5, thereby permitting free movement of ribbon 3 over spring 1. Spring 1 has a central ring 1a, which fits over a post 9 in cartridge 7. Rotation of spring 1 is prevented by notch 1b in element 1, which meshes with wall 11 of cartridge 7. Fig. 1 shows the status when ribbon 3 is not being fed.