Platen Index Motor Mounted Within Platen
Original Publication Date: 1987-Feb-01
Included in the Prior Art Database: 2005-Feb-01
A platen for a typewriter or printer has its indexing motor mounted within its hollow interior to increase the available space within the typewriter or printer for other elements. A platen 1 has a motor 2, which may be a small stepper motor or an encoded DC motor, mounted within its hollow interior and driving the platen 1. The platen 1 includes a plastic outer cover 3 and an inner metal portion 4 having a ring gear 5 secured thereto. The platen 1 has its ends rotatably supported in end caps 6 and 7 with each of the end caps 6 and 7, having a large hole (shown at 8 in the end cap 7) for ventilation. The motor 2 has a sun gear 9 on its output shaft and meshing with a planetary gear 10, which also meshes with the ring gear 5. Thus, the motor 2 can rotate the platen 1 in either direction.