Patent GB-1321903-A (GB)
Title: Electrically operated typewriter
IPC: B41J11/14
Filed: 1970-06-24
Abstract: 1321903 Typewriters ECOFON VERKAUFSGESELLSCHAFT PROBST KG 24 June 1970 [26 June 1969] 30737/70 Heading B6F A type-disc 5 with radial resilient arms is clutched to a continuously driven electric motor 12. Operation of micro-switch keyboard 1 causes the type-disc to be arrested in the selected position by electromagnetic engaging means 7 with the simultaneous operation of electromagnetic hammer operating means 13, 14, 15. Both electromagnetic means rely on springs to cause movement of their armatures when de-energized. The armature (29, Fig. 2) of the electromagnetic engaging means 7 carries a crown gear (28) which is moved into emgagement with a co-axial matching crown gear (27) fasterned to type-disc 5, to selectively arrest the same. As an alternative, the crown gear (28) could be mounted on a moving coil magnet. The slipping clutch between the pulley 8 (driven by the motor 12) and the shaft 6 of the type-disc 5, in the particular embodiment, comprises a coil spring (53, Fig. 2), one end of which is fastened to the pulley 8 and the other end of which is fastened to an arm (48) radially extending from the shaft 6. The pulley 8 additionally carries an eccentrically mounted, axially extending pin (49), which abuts the arm (48) and defines the relative angular position between the type-disc and the pulley, when the disc is being driven. However, when the disc is arrested, the pulley continues to rotate, the pin (49) moving out of engagement with the arm (48) and the spring (53) taking up the relative movement. Moving type carriage. As an alternative to the particular embodiment illustrated, which has a fixed type carriage and a moving platen, the type carriage may move in the letter space direction. The drive to the type disc may be achieved with a splined shaft parallel to the axis of the platen and suitable crown and bevel gears. In this way proper synchronization between the disc 5 and the electric selection mechanism (which includes a rotating contact finger 54, Fig. 2) may be achieved. The type-disc 5 may also be driven by a timing belt trained over two guide pulleys on a laterally movable spring loaded slide (not illustrated). This allows the type-disc to be moved not only in the letter space direction, but also for case shifting. Case shift. As stated above, the type-disc may be moved for case shifting, but in the particular embodiment, it is the platen 3 which is pivotally mounted at (22, Fig. 3) for movement by an electromagnet (25, Fig. 2). The platen carriage 2 travels on bearing balls (20) set into a guide rail (21) pivoted to the horizontal shaft (22). Escapement mechanism. An electromagnet 16, Figs. 1 and (3), when de-energized, causes an escapement (58) to pivot with respect to escapement rack (58<SP>1</SP>), permitting the carriage to move one step. Inking mechanism. A conventional ink ribbon mechanism may be employed, but it is preferred to ink the types (61, 62, Fig. 5) by means of a train of engaged rollers which transfer ink from a well to the disc 5, or by a single, porous inking roller saturated with ink. This roller could be hollow with its interior filled with ink. The roller could be lifted off the disc between impressions by electromagnetic means.