Typewriter Ribbon Cartridge Take Up Spool Bias Spring With Loop Unwind Control
Original Publication Date: 1982-Jan-01
Included in the Prior Art Database: 2005-Feb-08
In a typewriter cartridge in which a drive wheel 10, such as illustrated in Fig. 1, bears against the outer diameter of the ribbon take-up spool 11, as the take-up spool 11 gains in diameter due to take-up ribbon build-up, the spools 10 and 11 will tend to a separate. Conventionally, a spring may be employed intermediate the driver spool 10 and driven take-up spool 11. However, it is desirable that the tension within the spring remain uniform and not increase, so that the force required to effect rotation of the driver spool or driver 10 does not increase with increasing diameter of the ribbon take-up spool.