Ink jet printing systems

Ink jet printing apparatus comprising:

• a plurality of ink jets;
• means mounting the jets in a matrix for non-contact printing of patterns of dots to form characters on a target surface moving past the jets, by selective squirting of drops of ink from the jets,
• each jet comprising an elongate tubular member having an outlet nozzle constituting a valve seat at one end thereof, said seat having an orifice for ejection of drops of ink,
• said tubular member having an ink chamber therein for holding ink under pressure for delivery through the orifice, said chamber being defined by the valve seat and by means sealing against escape of ink from the chamber,
• a valve stem extending longitudinally in said tubular member having a valve member at its end toward the seat engageable with the seat to block flow of ink through the orifice in the seat,
• the valve stem being movable longitudinally in said tubular jet member for closing the valve member against the seat and for opening it for ejection of a drop of ink through the orifice,
• means for supplying the ink chambers of said tubular jet members with ink under pressure,
• and a plurality of solenoids, one for each jet, each connected to a respective valve stem for actuating the latter,
• wherein the mounting means for the jets comprises an ink manifold for holding ink under pressure, said manifold having a front wall and a back wall spaced from each other and defining therebetween a manifold chamber for holding ink under pressure, said walls having a plurality of holes receiving the tubular jet members with the latter extending through the holes in the back wall across the manifold chamber into the holes in the front wall,
• each tubular jet member being sealed in the holes and having a lateral port in communication with the manifold chamber for feeding ink from the manifold chamber to the ink chamber in the tubular jet member.

An ink jet printhead for an ink jet printing system for ink jet printing of messages on objects being fed forward one after another in a predetermined path, said printhead being adapted to be positioned adjacent said path to print the message on the objects as they travel forward in said path, said printhead comprising:

• a plurality of ink jets arranged in a matrix with the jets in close array and in a pattern for ejection of drops of ink across a gap to a surface of an object travelling by the printhead to print dots on said surface in patterns forming selected characters for said messages;
• each jet comprising:
• an elongate tubular member having an outlet nozzle constituting a valve seat at one end thereof, said seat having an orifice for ejection of drops of ink,
• said tubular member having an ink chamber therein for holding ink under pressure for delivery through the orifice, said chamber being defined by the valve seat and by means sealing against escape of ink from the chamber;
• a valve stem extending longitudinally in said tubular member having a valve member at its end toward the seat engageable with the seat on the inside to block flow of ink through the orifice in the seat;
• the valve stem being movable longitudinally in said tubular jet member for closing the valve member against the seat and for opening it for ejection of a drop of ink through the orifice;
• means for supplying ink under pressure to the ink chambers of said tubular jet members;
• a plurality of solenoids, one for each jet, said solenoids being spaced away from valve seats and more widely spaced relative to one another than the jets in said matrix;
• drive means interconnecting each solenoid and the valve stem of the respective jet for actuation by each solenoid of the respective valve stem and the respective valve member,
• wherein the drive means interconnecting each solenoid and the respective valve stem comprises a flexible drive wire allowing for the wider spacing of the solenoids than the jets,
• having a solenoid support tube extending from each tubular member, at least some of said tubes flaring outwardly for said wider spacing of the solenoids than the jets, each solenoid being mounted on the end of its respective support tube away from the respective tubular member, each solenoid having a plunger, the flexible drive wire for each valve stem being interconnected with the plunger of the respective solenoid and extending through the respective solenoid support tube, and
• wherein as to each jet the means sealing against the escape of ink from the respective chamber comprises a resilient diaphragm, the valve stem of and the drive wire for each jet being secured to the respective diaphragm at opposite sides thereof.

A system for ink jet printing of messages on objects being fed forward one after another in a predetermined path, said system comprising:

• a plurality of ink jet printheads positioned adjacent said path to print the messages on the articles as they travel forward in said path;
• each printhead comprising a plurality of ink jets arranged in a matrix and adapted for ejection of drops of ink across a gap to a surface of an object travelling by the printhead to print dots on said surface in patterns forming selected characters for said messages;
• means for supplying ink to the jets;
• a plurality of electrically actuated valve means, one for each jet, each adapted for electrical operation for ejection of a drop of ink from the respective nozzle;
• a terminal including a keyboard for entering message data;
• a message bank having a microcomputer interconnected with the terminal for processing data received from the terminal and storing the data for a plurality of messages;
• a plurality of controllers, one for each printhead, each including a microcomputer interconnected with the bank for processing data for a selected message rceived from the bank and storing the data;
• means for effectng transfer of data for a selected message from the bank to a selected controller for storage in that controller and for transferring predetermined information from each microcomputer of each controller to the microcomputer of the message bank;
• each controller having an output circuit interconnected with the mirocomputer thereof and with the respective printhead for receiving output of data for the selected message from that microcomputer and converting the data to driving signals for the printhead valve means for actuating the latter to print the selected message;
• wherein each jet of each printhead comprises:
• an elongate tubular member having an outlet nozzle constituting a valve seat at one end thereof, said seat having an orifice for ejection of drops of ink;
• said tubular member having an ink chamber therein for holding ink under pressure for delivery through the orifice, said chamber being defined by the valve seat and by means sealing against escape of ink from the chamber;
• a valve stem extending longitudinally in said tubular member having a valve member at its end toward the seat engageable with the seat to block flow of ink through the orifice in the seat;
• the valve stem being movable longitudinally in aid tubular jet member for closing the valve member against the seat and for opening it for ejection of a drop of ink through the orifice,
• said ink supply means supplying the ink chambers of said tubular jet members with ink under pressure;
• each printhead having a plurality of solenoids, one for each jet, each connected to a respective alve stem for actuating the latter;
• wherein said solenoids are spaced away from the valve seats and more widely spaced relative to one another than the jets in said matrix;
• wherein each solenoid is connected to the respective valve stem by drive means comprising a flexible drive wire allowing for the wider spacing of the solenoids than the jets;
• having a solenoid support tube extending from each tubular member, at least some of said tubes flaring outwardly for said wider spacing of the solenoids than the jets, each solenoid being mounted on the end of its respective support tube away from the rspective tubular member, each solenoid having a plunger, the flexible drive wire for each valve stem being interconnected with the plunger of the respective solenoid and extending through the respective solenoid support tube, and
• wherein as to each jet the means sealing against the escape of ink from the respective chamber comprises a resilient diaphragm, the valve stem of and the drive wire for each jet being secured to the respective diaphragm at opposite sides thereof.

A printing jet discharge head assembly for applying characters to an article, said head assembly comprising:

• a chamber for receiving and holding printing liquid under pressure;
• a plurality of outlet orifices in said chamber for discharging printing liquid therefrom, said outlet orifices being arranged sufficiently close together to form legible characters from the discharges of said orifices;
• a plurality of closure elements within said chamber and operatively associated with respective outlet orifices, said closure elements being selectively displacable toward and away from said outlet orifices for closing and opening respective orifices;
• resilient means to urge said closure elements toward said outlet orifices for closing said orifices;
• a plurality of pulling means for selectively moving said closure elements away from said outlet orifices for opening said orifices to discharge printing liquid therefrom to form the characters, said pulling means comprising a plurality of selectively operable actuators located outside said chamber, said actuators being of a size too large to enable direct coupling to said closely spaced closure elements, and a corresponding plurality of flexible pulling elements, each of said flexible pulling elements connecting a respective one of said actuators with a respective one of said closure elements to enable said actuators to selectively withdraw said closure elements from said orifices, the flexible pulling elements obtaining the coupling of the actuators to the closure elements while permitting a substantially unrestricted location of said actuators relative to said chamber and closure elements.

A system for ink jet printing of messages on objects being fed forward one after another in a predetermined path, said system comprising:

• a plurality of ink jet printheads positioned adjacent said path to print the messages on the articles as they travel forward in said path;
• each printhead having an ink chamber;
• means defining a plurality of outlet jet orifices arranged in a matrix and adapted for ejection of drops of ink across a gap to a surface of an object travelling by the printhead to print dots on said surface in patterns forming selected characters for said messages;
• a plurality of valve members which are selectively displaceable to open and close respective orifices;
• resilient means arranged to urge said valve members to close the orifices;
• a plurality of electrical pulling means actuable to effect pulling and associated with respective valve members and spaced therefrom;
• a plurality of elongate pulling elements connecting the valve members to respective electrical pulling means so that the electrical pulling means are actuable to pull respective valve members against the urging of the resilient means to open respective orifices;
• means for supplying ink to the chamber;
• a terminal including a keyboard for entering message data,
• a message bank having a microcomputer interconnected with the terminal for processing data received from the terminal and storing the data for a plurality of messages,
• a plurality of controllers, one for each printhead, each including a microcomputer interconnected with the bank for processing data for a selected message received from the bank and storing the data,
• means for effecting transfer of data for a selected message from the bank to a selected controller for storage in that controller,
• each controller having an output circuit interconnected with the microcomputer thereof and with the respective printhead for receiving output of data for the selected message from that microcomputer and converting the data to driving signals for the electrical pulling means for actuating the valve members to print the selected message.