Portable electronic typewriter

Claim 2

In an electronic typewriter comprising a platen; a carriage which is movable in front of said platen and on which is mounted a print device; an electric motor having a bidirectionally rotating rotor; motion converting means for converting the rotation of said rotor to motion of said carriage including a rotatable member permanently operating on said carriage for its movement wherein said electric motor is selectively actuatable for moving the carriage in two opposite directions in front of the platen; and setting means actuatable for arresting said rotatable member for a fine positioning of said carriage, the improvement comprising rectifying means for exactly arresting said carriage in front of a desired position of the platen, independently of the direction of movement of said carriage, said rectifying means comprising: arrest means of said setting means capable of operating solely unidirectionally on said rotatable member; first means defining an intermediate coarse position at a first side of said desired position along a given direction; a control circuit which first actuates the electric motor for coarsely moving the carriage along one or another of the two opposite directions from a current position up to said intermediate coarse position then deactuates said electric motor once the intermediate coarse position has been reached; and second means for causing said control circuit to actuate again the electric motor and for actuating said setting means for unidirectional movement of the carriage from said coarse intermediate position to said desired position as defined by the unidirectional arrest of said rotatable member by actuated arresting means.

Claim 3

A typewriter according to claim 1, wherein said motion converting means further comprises friction means interposed between the rotor of said electric motor and said rotatable member to permit the rotation of said rotor when the rotatable member has been arrested by said actuated setting means.

Claim 4

An electronic typewriter according to claim 2, wherein said second means cause said control circuit to actuate said electric motor for a time longer than the time necessary to enable said carriage to reach said desired position.

Claim 5

A typewriter according to claim 1, further comprising a coarse transducer for the position of the carriage, wherein said transducer comprises a movable portion synchronous with said rotatable member and a detecting portion which produces a position signal in response to the movement of said movable portion and wherein the control circuit actuates said electric motor and said setting means under the control of said position signal.

Claim 6

A typewriter according to claim 4, wherein the movable portion of said transducer comprises a rotary ring having sectors which are magnetized alternately and the detecting portion of the transducer comprises detector means switchable under the action of the magnetic field of said sectors in a reference zone adjacent to the ring and wherein each field switching action is associated with a position of the carriage in front of a given region of another desired position of the platen.

Claim 7

A typewriter according to claim 4, wherein said motion converting means further comprises a pair of friction members interposed between the rotor of said electric motor and said rotatable member to permit further rotation of said rotor when the rotating member has been arrested by said actuated setting means, and wherein said friction members comprise a first portion permanently rotated by the rotor of said motor and a second portion permanently operating on the movable portion of the transducer.

Claim 8

A typewriter according to claim 6, wherein said motion convertiing means comprises a rotating wheel permanently operating on said carriage for its movement and provided with a peripheral tooth arrangement, wherein the setting means comprise a tooth engageable with the spaces of the peripheral tooth arrangement of the rotating wheel and wherein the movable portion of said tranducer is carried by one of said pair of friction members synchronous with said wheel.

Claim 9

A typewriter according to claim 7, wherein said tooth is actuated by a solenoid controlled by the said control circuit.

Claim 10

A typewriter according to claim 8, wherein said peripheral tooth arrangement has a sawtooth configuration.

Claim 11

A typewriter according to claim 1, wherein said rotating member is provided with a peripheral tooth arrangement, and wherein said setting means comprise a tooth engageable with the spaces of the peripheral tooth arrangement of the rotating member.

Claim 12

A typewriter according to claim 1, wherein said motor is mounted on said carriage and said motion converting means comprises an elongated member mounted parallel to the platen, and an intermediate member rotatably mounted on said carriage and operatively connecting the rotor of said motor with said elongated member for conversion of the rotation of said rotor into a translational movement of said carriage.

Claim 13

A typewriter according to claim 11, wherein said elongated member is a flexible wire and said intermediate member comprises a drum on which a portion of said flexible wire is wound.

Claim 14

An electronic typewriter comprising a rotatable selecting member defining a plurality of given positions; an electric motor having a rotor and actuatable for bidirectionally rotating its rotor; motion transmitting means for transmitting the rotation of said rotor to said selecting member including a pair of friction members interposed between said rotor and said selecting member to permit a free movement of said rotor also when said selecting member is held arrested; a coarse transducer for said given positions of the selecting member having a rotatable portion synchronous with the selecting member and a detecting portion which produces a coarse position signal in response to each of the given positions of said selecting member; means defining an intermediate coarse position at a first side of a desired given position along a given direction; setting means actuatable for fine arresting of said selecting member; and circuit means responsive to said position signal for first actuating said electric motor for coarsely and selectively moving the selecting member in one of said two opposite directions from a current position to said intermediate and then deactuating said electric motor once the intermediate coarse position has been reached position; and wherein said circuit means reactivate said motor and actuate said setting means for unidirectional movement of said selecting member from said intermediate position to said desired position as defined by the arrest of said rotatable member by said actuated setting means.

Claim 15

An electronic typewriter comprising a rotatable selecting member defining a plurality of given positions; an electric motor having a rotor and actuatable for bidirectionally rotating its rotor; motion transmitting means for transmitting the rotation of said rotor to said selecting member including a pair of friction members interposed between said rotor and said selecting member to permit a free movement of said rotor also when said selecting member is held arrested; a coarse transducer for said given positions of the selecting member having a rotatable portion synchronous with the selecting member and a detecting portion which produces a coarse position signal in response to each of the given positions of said selecting member; means defining an intermediate coarse position at a first side of a desired given position along a given direction; setting means actuatable for fine arresting of said selecting member; and circuit means responsive to said position signal for first actuating said electric motor for coarsely and selectively moving the selecting member in one of said two opposite directions from a current position to said intermediate and then deactuating said electric motor once the intermediate coarse position has been reached position; and wherein said circuit means reactivate said motor and actuate said setting means for unidirectional movement of said selecting member from said intermediate position to said desired position as defined by the arrest of said rotatable member by said actuated setting means.

Claim 16

An electronic typewriter according to claim 13, wherein said circuit means arrest again said motor during the unidirectional movement of said selecting member in response to a position signal associated with the desired position of said selecting member and after a time sufficient to the operation of said actuated setting means.

Claim 17

A typewriter according to claim 13, wherein said setting means comprise a tooth and a rotatable member, wherein said rotatable member is rotating in synchronism with the movement of the selecting member, and wherein said rotatable member is provided on its periphery with recesses of a sawtooth configuration, and further comprising an electromagnet connected with said tooth and actuatable by said circuit means for causing said tooth to engage one of said recesses to arrest said rotatable member.

Claim 18

A typewriter according to claim 13, wherein the movable portion of said coarse transducer comprises a rotary ring having sectors which are magnetised alternately and the detecting portion comprises a detector for the magnetic field of the sectors in a reference zone adjacent to the ring and wherein each field switching action is associated with the region of each one of said given positions of said selecting member.

Claim 19

An electronic typewriter comprising a platen; a carriage which is movable in front of said platen and on which is mounted a print device; an electric motor having a bidirectionally rotatable rotor; motion converting means operated by said rotor for moving the carriage in two opposite directions in front of the platen, said motion converting means comprising a flexible wire extending substantially parallel to the platen, a drum member on which a portion of said wire is wound and friction means interposed between said rotor and said drum member; setting means actuatable for precisely arresting the carriage in given positions in front of said platen, said setting means comprising a toothed wheel synchronous with said drum member and a positioning tooth actuatable for engaging and arresting said toothed wheel and wherein said friction means enable said rotor to rotate when the toothed wheel is arrested by said positioning tooth; a coarse transducer for defining coarse positions of the carriage associated with said given positions, wherein said transducer comprises a movable portion which is synchronous with said toothed wheel and a detecting portion which produces a position signal responsive to the rotation of said movable portion and univocally associated with the coarse positions of said carriage; means defining an intermediate coarse position at a side of a desired position of said given positions along a given direction; a control circuit responsive to said position signal for first actuating said electric motor for coarsely moving the carriage in one or another of the two opposite directions from a current position up to said intermediate coarse position and then deactuating said electric motor once the intermediate coarse position has been reached; and means for causing said control means to actuate again said electric motor and for actuating said setting means for unidirectional movement of the carriage from said coarse intermediate position to said desired position as defined by the arrest of said toothed wheel by actuated positioning tooth.

Claim 20

An electronic typewriter comprising a platen; a carriage which is movable in front of said platen and on which is mounted a print device; an electric motor having a bidirectionally rotatable rotor; motion converting means operated by said rotor for moving the carriage in two opposite directions in front of the platen, said motion converting means comprising a flexible wire extending substantially parallel to the platen, a drum member on which a portion of said wire is wound and friction means interposed between said rotor and said drum member; setting means actuatable for precisely arresting the carriage in given positions in front of said platen, said setting means comprising a toothed wheel synchronous with said drum member and a positioning tooth actuatable for engaging and arresting said toothed wheel and wherein said friction means enable said rotor to rotate when the toothed wheel is arrested by said positioning tooth; a coarse transducer for defining coarse positions of the carriage associated with said given positions, wherein said transducer comprises a movable portion which is synchronous with said toothed wheel and a detecting portion which produces a position signal responsive to the rotation of said movable portion and univocally associated with the coarse positions of said carriage; means defining an intermediate coarse position at a side of a desired position of said given positions along a given direction; a control circuit responsive to said position signal for first actuating said electric motor for coarsely moving the carriage in one or another of the two opposite directions from a current position up to said intermediate coarse position and then deactuating said electric motor once the intermediate coarse position has been reached; and means for causing said control means to actuate again said electric motor and for actuating said setting means for unidirectional movement of the carriage from said coarse intermediate position to said desired position as defined by the arrest of said toothed wheel by actuated positioning tooth.

Claim 21

An electronic typewriter according to claim 17, wherein said electric motor, said drum member and said setting means are mounted on said carriage.

Claim 22

An electronic typewriter according to claim 17, wherein said motion converting means comprise a rotating support fixing said drum member and said toothed wheel, wherein said rotor drives a pinion engaging with an intermediate gear rotatably supported by said rotating support and wherein said friction means comprises a first portion fixed to said rotating support and a second portion fixed to said intermediate gear.

Claim 23

An electronic typewriter according to claim 19, wherein said toothed wheel has a plurality of peripheral teeth having a sawtooth configuration, wherein each of said peripheral teeth has a steep surface and an inclined surface, and wherein the steep surface of one of said teeth is arrested against the actuated positioning tooth during the unidirectional movement of the carriage from the coarse intermediate position to said desired position.