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US 4,485,386 AGranted
Ink jet dot printer
AssigneeIng. C. Olivetti & C., S.p.A.
InventorsGiandomenico Dagna, Enrico Manini, Giorgio Tadini
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AssigneeIng. C. Olivetti & C., S.p.A.
InventorsGiandomenico Dagna, Enrico Manini, Giorgio Tadini
Estimating the term…
The ink jet dot printer comprises a head mounted on a carriage movable along a platen supporting the paper and is formed by a plurality of tubes and piezoelectric transducer for ejecting the ink, which are supported by two parallel plates spaced from one another, between which a polymerizable resin is cast to form a single block. The tubes are aligned in a single row F--F' in a direction inclined with respect to the printing line, in such manner that the distance between the extreme tubes measured perpendicularly to the printing line is equal to the maximum height of the characters. On the outside of the front plate supporting the tubes there is fixed a thin plate bearing a row of nozzles, each of which is aligned with the corresponding ejector tube. The expulsion of the drops of ink is obtained by means of the compression exerted on the tubes by the piezoelectric transducers activated in parallel by electric pulses generated by an energizing circuit under the control of a driving logic circuit by means of which it is possible to vary the slope of the printed characters and obtain bidirectional printing at high speed.
An ink jet dot printer comprising a head mounted on a carriage movable with respect to a printing support and having a plurality of ejecting tubes parallel to one another and in an inclined plane with respect to the movement of the carriage, each tube being provided with a piezoelectric transducer selectively activable for expelling a drop of ink through a corresponding nozzle at predetermined printing positions in response to an electric signal, said tubes being placed in a hollow supporting structure and fixed to a pair of parallel spaced plates of said structure perpendicular to said tubes, the cavity of said structure being filled with a polymerizable resin, to form a single block with the plates, the tubes and the resin, the combination comprising a plurality of flexible conduits connected between an end of the tubes projecting beyond the back plate of said pair and an auxiliary ink reservoir, the conduits being supported by a fixed cylindrical drum mounted on the carriage and passed around the drum alternately in opposite directions for one and a half turns so as to minimize the axial space occupied by the conduits on the drum.
An ink jet dot printer comprising a head mounted on a carriage movable with respect to a printing support and having a plurality of parallel ink ejecting tubes, in a plane so inclined with respect to the movement of the carriage that the vertical distance between the first and the last of the tubes, is equal to the maximum height of the characters to be printed, each tube being provided with a piezoelectric transducer selectively activable for expelling a drop of ink through a corresponding nozzle in predetermined printing positions in response to an electric signal, and a driving logic circuit for generating said electric signals comprising a memory for reading and writing information appertaining to the successive columns of dots of a matrix of the characters to be printed, addressing means connected to the memory and controlled by a control unit for addressing the information in predetermined address locations of said memory shifted from one another by a settable number of address locations, and an adder connected to said addressing means for adding said settable number of locations to the address location of the information of a generic column of dots to be printed, said adder being connected to an entering device for forcing into the adder said settable number of address locations whereby said addressing means address said column information in consecutive address locations in cyclic succession and said control unit permits the reading of column information of the dots to be printed at predetermined address locations shifted from one another by said settable number of locations.
Driving circuit for an on demand ink jet printer having a plurality of ink ejecting tubes mounted on a movable carriage and arranged in a plane inclined with respect to the movement of the carriage, each tube having a nozzle and a transducer to expell an ink droplet, said circuit comprising a character generator to generate character information representative of the character to be printed arranged in dot column patterns according to a predetermined matrix, a read-write memory for storing said information, addressing means connected to said memory and controlled by a control unit, to cyclically address said dot column information in selected address locations of said memory, an adder connected to said addressing means to add a selectable number to the serial number of any preceding address location and an entering device for forcing into said adder said selected number, whereby said dot column information is addressed at address locations shifted from one another by said selected number of locations.
An on demand ink jet printing head comprising an ink ejecting tube associated with a transducer selectively operable for expelling a drop of ink through a corresponding nozzle, said tube and said transducer being secured to a supporting structure, an ink reservoir carried by said structure, and ink conducting tube connecting said reservoir and said ejecting tube made of a flexible material and having a length greater than the distance between the ejecting tube and the reservoir, the improvement comprising a winding member carried by said structure between said ejecting tube and said reservoir, said member holding said ink conducting tube in a wound arrangement to reduce the dimension of said structure.
An on demand ink jet printing head comprising a head mounted on a carriage movable with respect to a printing support and including an elongated ink ejecting tube associated with a transducer selectively operable for expelling a drop of ink through a corresponding nozzle, said tube and said transducer being placed in a hollow supporting structure and fixed to a pair of parallely spaced plates perpendicular to said tube, said plates defining a first cavity therebetween and an adjacent cavity, said first cavity being filled with a polymerizable resin to form a single block with said ejecting tubes, said plates and said resin, an auxiliary ink reservoir, fixed to the structure and connected to a stationary main ink tank, a flexible ink conducting tube for connecting said ejecting tube to said reservoir, said flexible tube having a length greater than the distance between said ejecting tube and said reservoir, and a supporting member placed into said adjacent cavity to hold said flexible conducting tube in a wound arrangement into said adjacent cavity, whereby the transverse dimension of said structure relative to the carriage movement is limited.
Dependencies are inferred from the claim text.