Abstract: A method of sharing a printer between a plurality of users on a computer network includes attaching host-based networking hardware to the printer. A network communication protocol defines a command channel and a data channel. Only one of the users is allowed to own the data channel at any single point in time. The host-based networking hardware is instructed to accept information on the data channel only from the user that owns the data channel.

Abstract: A method of sharing a printer between a plurality of users on a computer network includes attaching host-based networking hardware to the printer. A network communication protocol defines a command channel and a data channel. Only one of the users is allowed to own the data channel at any single point in time. The host-based networking hardware is instructed to accept information on the data channel only from the user that owns the data channel.

Abstract: A print head having an ink reservoir therein is made by forming, in a one-shot plastic injection molding step, a rigid monolithic frame including high melt temperature material having an opening therein extending from a first side to a second side, and first and second bonding surfaces surrounding the opening and facing the first and second sides, respectively. First and second thin flexible films are adhesively secured to the first and second bonding surfaces, respectively. The adhesive material may be a hot melt adhesive or dry adhesive films pre-formed to the shape of the bonding surfaces. By securing the flexible films to the bonding surfaces adhesively, rather than by heat staking, it is not necessary to form the frame of different materials during two separate molding steps.

Abstract: A print head having an ink reservoir therein is made by forming, in a one-shot plastic injection molding step, a rigid monolithic frame comprising high melt temperature material having an opening therein extending from a first side to a second side, and first and second bonding surfaces surrounding the opening and facing the first and second sides, respectively. First and second thin flexible films are adhesively secured to the first and second bonding surfaces, respectively. The adhesive material may be a hot melt adhesive or dry adhesive films pre-formed to the shape of the bonding surfaces. By securing the flexible films to the bonding surfaces adhesively, rather than by heat staking, it is not necessary to form the frame of different materials during two separate molding steps.

Abstract: Disclosed is an ink jet printhead apparatus for modulating drop size. Drop size modulation is achieved by providing an ink jet printhead chip for use in an ink jet printhead having a cavity in communication with a supply of ink and a nozzle. The chip includes an unitary actuator having a first active section and a second active section. The first and second active sections are defined at a substantially equal distance from the nozzle by a location of attachment of at least three conductors.

Abstract: Disclosed is an ink jet printhead apparatus for modulating drop size. Drop size modulation is achieved by providing an ink jet printhead chip for use in an ink jet printhead having a cavity in communication with a supply of ink and a nozzle. The chip includes an actuator having a first active section and a second active section. The first and second active sections are positioned at a substantially equal distance from the nozzle.

Abstract: An ink jet printing apparatus is provided comprising a print cartridge including a heater chip and a nozzle plate coupled to the heater chip. The heater chip has first, second, third and fourth heating elements, and the nozzle plate has a plurality of primary and secondary nozzles. The primary nozzles include first and second nozzles positioned in first and second nozzle plate columns and the secondary nozzles include third and fourth nozzles positioned in third and fourth nozzle plate columns. Each of the nozzles has one of the heating elements associated therewith for generating energy to discharge ink therefrom. The apparatus further includes a driver circuit, electrically coupled to the print cartridge, for applying firing pulses to the heating elements.

Abstract: Method and apparatus is described for detecting faults, such as cracks, in ink jet printhead heater chips using a resistor on the heater chip. The resistor is located adjacent to at least one edge of the heater chip. One method, for example, includes the steps of measuring the resistance of the resistor at a first temperature and comparing the measured electrical resistance to a theoretical calculated resistance. Another method, for example, includes the steps of measuring the resistance at a first temperature, heating the chip, and measuring the resistance at a second temperature. Faults are detected by comparing expected changes in resistance or temperature to measured changes.

Abstract: An ink jet print head identification system for providing print head identifying information to the electronics of an ink jet printer includes one or more parallel load, serial out, dynamic shift registers integrated into a print head chip having a plurality of address lines interconnecting the printer electronics and print head electronics. Each shift register is programmed or encoded with a single digital bit. In one embodiment, a voltage pulse (load signal) received on a single chip address line by a plurality of shift registers loads the input of each encoded register with the register's own encoded bit. Two of the address lines provide each of the registers with successive sequential clock signals to serially shift the encoded information to an output device where the print head identifying information is read by the printer electronics. Other embodiments of the invention may employ any number of encoded registers independently of the number of available address lines.

Abstract: An ink jet printing apparatus includes a printhead controller including a printhead driver circuit having a set of ink jet nozzle control outputs and a printhead select circuit having a plurality of printhead select outputs. A plurality of printheads are provided, wherein each printhead includes a plurality of ink jet nozzles, a plurality of individually controllable ink jet nozzle firing circuits, and a printhead enable circuit, wherein the printhead enable circuit is electrically coupled between the plurality of individually controllable ink jet nozzle firing circuits and the set of ink jet nozzle control outputs, and wherein the printhead enable circuit is electrically coupled to one of the plurality of printhead select outputs and enables the electrical conduction of the plurality of controllable ink jet nozzle firing circuits upon receipt of a printhead select signal from one of the printhead select outputs of the printhead select circuits.

Abstract: An ink jet printhead includes a chip layer having a via for receiving ink, and having at least one actuator. A barrier layer is disposed adjacent the chip layer, and forms at least one throat which has a width and a cross-sectional area. The barrier layer also forms at least one bubble chamber, with each throat adapted to receive ink from the via and provide it to the respective bubble chamber. A nozzle layer is disposed adjacent the barrier layer, opposite the chip layer, and forms at least one nozzle for ejecting ink from the respective bubble chamber when the ink is energized by the associated actuator. At least one post is disposed proximate the throat, and extends part way between the chip layer and the nozzle layer. The post forms one or more gates through which the ink must pass from the via to the at least one throat.

Abstract: In an active ink jet printhead chip (13) a layer of boron-phosphorus doped silicate glass (BPSG) immediately underneath the heaters followed by a silicon dioxide layer. This insulates the substrate during the fire pulse of its heater, yet allows thermal energy to diffuse into the silicon during the time between firing pulses.

Abstract: Improved methods for fabricating the ink feed slots in silicon substrate for use in thermal ink-jet print heads is disclosed. One method involves the partial anisotropic etching of an ink feed slot in a silicon substrate for use in aligning the electrical resistive elements on one surface of the substrate. Another embodiment involves laser drilling alignment holes and anisotropically etching the substrate. In both methods, at least one photoresist masking and development step is eliminated thereby reducing fabrication time and alignment difficulties for locating the feed slots relative to the electrical resistance elements and increasing product yield.