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US 4,390,293 AGranted
Electronic typewriter
AssigneeIng. C. Olivetti & C., S.p.A.
InventorsGiuseppe Gubau, Domenico Roano, Giovanni Quaranti
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AssigneeIng. C. Olivetti & C., S.p.A.
InventorsGiuseppe Gubau, Domenico Roano, Giovanni Quaranti
Estimating the term…
The electronic typewriter comprises a character-carrier disc with flexible blades, which is mounted on a carriage which is movable transversely with respect to the typing roller by means of a stepping motor. Mounted on the carriage is a motor for selecting the character, a striker hammer, a positioning device and an actuating motor which actuates the hammer and the positioning device and which also provides for activating the operations by means of a typing ribbon and by means of a correction ribbon. The selection motor is supplied by a servo control of digital type which imparts to the motor a speed which is proportional to the positional error, positioning the blade of the character to be typed with a maximum error of .+-.1/4 of a pitch. The positioning device then provides for correction of the character, engaging a recess of a positioning disc which is synchronous with the character-carrier disc.
An electronic typewriter comprising a character-carrier disc having flexible fingers, each one carrying a character, a selection motor having the rotor connectable with the disc for the rotation thereof, a digital transducer for revealing incremental rotations of said character-carrier disc and having a plurality of switching area associated with said fingers, and sensing means revealing the presence of said switching areas on a predetermined position for generating a transducer position signal, wherein said transducer position signal is representative of a coarse location of each of said fingers in front of the point of typing, a velocity servo-control circuit for the selection motor including a first means responsive to angular distances of the desired character from the coarse location for generating a corresponding desired velocity signal, second means responsive to each transducer position signal and to a preceding transducer position signal for generating an actual velocity signal, and motor actuating means responsive to said actual velocity signal and to said desired velocity signal for causing the rotor of said selecting motor to be rotated in accordance with a predetermined law of motion, wherein said velocity servo-control means arrests the rotor when the desired character reaches said coarse location in front of the point of typing, and means for fine positioning said desired character in front of the point of typing comprising a correction wheel mounted synchronously with said character-carrier disc and provided with a series of peripheral recess means associated with said fingers, tooth means actuatable for engaging with each of said series of recess means, and correction actuating means responsive to reached coarse location of said desired character for actuating said tooth means, and wherein the engagement of said tooth means with said recess means causes fine positioning of the desired character in front of the point of typing.
An electronic typewriter comprising a character-carrier disc having flexible fingers, each carrying a character, a shaft member for removably mounting said disc for serially positioning said characters in front of the point of typing, wherein said shaft member comprises a gear, a selection motor having a rotor fixing a pinion which engages with said gear for rotating said disc and reducing the speed of said disc with respect to the speed of the rotor, a position transducer including a rotational part fixed with said shaft member and having a plurality of switching areas associated with said fingers and sensing means revealing the presence of said switching areas on a predetermined position for generating a transducer position signal representative of a coarse location of each of said fingers in front of the point of typing, servo-control means for the selection motor responsive to the angular distance of the desired character from its coarse location for causing the rotor of said selecting motor to rotate said character-carrier disc and arrest it when the desired character reaches said coarse location in front of the point of typing, a correcting position wheel fixed on said shaft member having recess means on the periphery thereof associated with said fingers, tooth means actuatable for engaging with said recess means to fine position the desired character in front of the point of typing, and correction actuating means responsive to reached coarse location of the desired character for actuating said tooth means.
A typewriter comprising a character-carrier disc having flexible fingers, each one carrying a character, a selection motor having the rotor operatively connected with the disc for intermittently rotating the disc until a desired character is coarsely located in front of the point of typing, means for fine positioning said desired character in front of said point of typing comprising a correction wheel mounted synchronously with said character-carrier disc and provided with a series of peripheral positioning surfaces associated with said fingers, tooth means actuatable for engaging said positioning surfaces for fine positioning the character from said coarse position to said fine position in front of the point of typing, a hammer actuatable for the typing of the desired character, cam means for actuating said tooth means and said hammer, an operating motor having a rotatable rotor, and control means responsive to the coarse positioning of said desired character for causing the rotor of said operating motor to actuate said cam means.
An electronic typewriter comprising a print unit including:
Dependencies are inferred from the claim text.