Abstract: A rotary valve has a valve body with a pair of fluid ports providing fluid exits on a face of the valve body. The fluid ports are connected to corresponding fluid channels in the valve body extending between the fluid ports and fluid inlet connections to the valve body. A fluid control plate is positioned in contact with the face of the valve body and extends across the fluid ports. The control plate has a fluid channel therein which is dimensioned to extend between the fluid ports in one position of the valve plate. The valve plate is axially mounted on an output shaft of a drive motor which is connected to the valve plate by a coupling shaft. The face of the valve body and the contacting face of the valve plates are ground precisely flat and after hard anodizing are coated with a low friction coating such as molydisulphide. The motor is arranged to urge the valve plate parallel to and against the face of the valve body by the weight of the motor and the connecting elements between the motor and the valve.

Abstract: A ribbon cartridge in a movable print point printer remains stationary while the ribbon moves to and from the print point along a path of fixed length. The path length is established by a first flexible leader which extends from the cartridge to the print point and a second flexible leader which extends from the print point back to the cartridge. The cartridge includes a supply reel for storing ribbon before the ribbon advances to the movable print point and a take-up reel for storing ribbon after it returns from the movable print point. The flexible leader comprises a steel member having a transverse curvature for preventing the leaders from assuming a reverse curvature and maintaining a curvature of substantially constant radius.