Liquid ejection device with a commonly composed actuator and liquid ejector
View Patent ↗A liquid-ejection integrated circuit device includes a substrate that defines a plurality of ink inlet channels. Integrated circuitry is positioned on the substrate. A plurality of nozzle chamber structures is positioned on the substrate. Each nozzle chamber structure defines a nozzle chamber in fluid communication with a respective liquid inlet channel and a liquid ejection port in fluid communication with the nozzle chamber. A plurality of liquid ejection members is positioned in respective nozzle chambers. The liquid ejection members are displaceable to eject liquid from the liquid ejection ports. A plurality of elongate actuators are fast, at respective one ends, to the substrate to receive drive signals from the integrated circuitry and, at the other ends, to respective liquid ejecting members. The actuators and the liquid ejecting members have substantially the same composition of a structural layer interposed between a first conductive layer and a second conductive layer. The first conductive layer defines a heating circuit connected to the integrated circuitry and a discontinuation between the heating circuit and the liquid ejection member electrically to isolate the heating circuit from the liquid in the nozzle chamber.
1. A liquid-ejection integrated circuit device that comprises
a substrate that defines a plurality of ink inlet channels;
integrated circuitry positioned on the substrate;
a plurality of nozzle chamber structures positioned on the substrate, each nozzle chamber structure defining a nozzle chamber in fluid communication with a respective liquid inlet channel and a liquid ejection port in fluid communication with the nozzle chamber;
a plurality of liquid ejection members positioned in respective nozzle chambers and displaceable to eject liquid from the liquid ejection ports; and
a plurality of elongate actuators, each elongate actuator being fast, at one end, to the substrate to receive drive signals from the integrated circuitry and, at the other end, to a respective liquid ejecting member, the actuators and the liquid ejecting members having substantially the same composition of a structural layer interposed between a first conductive layer and a second conductive layer, the first conductive layer defining a heating circuit connected to the integrated circuitry and a discontinuation between the heating circuit and the liquid ejection member electrically to isolate the heating circuit from the liquid in the nozzle chamber.
2. A liquid-ejection integrated circuit device as claimed in claim 1 , in which the first conductive layer is configured so that the heating circuit defines a tapered slot that tapers inwardly toward the liquid ejection member so that a cross sectional area of the heating circuit reduces towards a point at which the actuator is fast with the substrate, thereby enhancing a heating operation of the heating circuit.
3. A liquid-ejection integrated circuit device as claimed in claim 1 , in which the first conductive layer is interposed between the structural layer and the substrate so that, as the heating circuit is heated with an electrical current from the integrated circuitry, a resultant differential thermal expansion of the actuator causes the liquid ejection member to be displaced towards the liquid ejection port.
4. A liquid-ejection integrated circuit device as claimed in claim 3 , in which the structural layer is glass and the first and second conductive layers are titanium nitride.
5. A liquid-ejection integrated circuit device as claimed in claim 4 , in which each drive and transistor circuit includes a plurality of trace wires that extend substantially transversely to its associated actuator, the first conductive layer defining a plurality of corrugations that correspond with the trace wires.
6. A liquid-ejection integrated circuit device as claimed in claim 3 , in which the integrated circuitry includes drive and transistor circuits for each actuator, the drive and transistor circuits being interposed between the substrate and respective, associated actuators.
7. A liquid-ejection integrated circuit device as claimed in claim 1 , in which the nozzle chamber structure has a cylindrical side wall and a roof defining the liquid ejection port, the liquid ejection member being in the form of a disc-like paddle spanning the nozzle chamber.