Abstract:
In an ink jet print head wherein a plurality of pumping chambers are provided for receiving ink and individually discharging the ink on demand in droplet form. The pumping chambers are formed on a substrate and defined in part by a continuous film of piezoelectric material extending over the substrate. Electrodes are electrically coupled on opposite sides of the piezoelectric film and positioned to define a plurality of distinct, electrically pulsed ink droplet drive elements operatively associated individually with the plurality of pumping chambers. An orifice for each chamber causes ink to be ejected from the chamber in response to demand electrical pulsation of the drive element for the respective chamber.
Abstract:
A multi-channel array, pulsed droplet ink jet printer comprises a plurality of channels each communicating with a respective nozzle. A side wall of each channel is formed as a shear mode piezo-electric actuator. Electrodes applied to the actuators enable electric fields to be applied such that the actuators move laterally in the direction of the field to change the liquid pressure in the channels for effecting droplet ejection through the channel nozzles. The actuators can be made in two parts so as to deform, in cross section, to a chevron formation.
Abstract:
An ink jet"drop-on-demand" printer has a number of parallel channels each containing ink. A thread of mercury extends longitudinally of each channel or pair of channels and is connected for electrical current flow. A magnetic field is applied orthogonally to the channel plane such that current flow in a selected channel causes electromagnetic deformation of the mercury thread. This leads to a pressure pulse in the ink causing ejection of an ink droplet. With a mercury thread shared between a pair of channels, current in the opposite sense results in droplet ejection from the opposite channel of the pair.
Abstract:
The present invention provides several methods for engraving gravure cylinders much more rapidly and at a higher resolution while, at the same time, reducing the engraving cost. The present invention employs a resist that is deposited onto the surface of a gravure cylinder. The resist is capable of being physically and/or chemically changed in response to being exposed to a form of actinic energy, such as a laser beam. The exposed areas of resist allow a material, such as chromium, to be plated onto the surface of the gravure cylinder to form walls that define cells therebetween. In use, the cells contain ink for printing the desired patterns of text and/or images.
Abstract:
A method of manufacturing one or more nozzles for an ink jet printhead initially comprises bonding a nozzle plate to the ink ejection end of the printhead. A mask is then secured in contact with the nozzle plate, the mask having a plurality of apertures each defining a respective nozzle exit. Laser radiation applied to the mask exposes the areas defined by the apertures to ablate the plate material between the nozzle exits on the external surface of the plate and corresponding nozzle inlets on the opposite surface of the plate. The assembly comprising the printhead, plate and mask is rocked during the exposure step to increase the area of the nozzle inlet relative to its outlet. Also, prior to the nozzle formation step, one or more ink troughs may be provided for supplying an external source of ink for each nozzle. The ink troughs, which may be formed using laser ablation techniques similar to those used in the formation of the nozzles, facilitate a continuous, positive flow of ink through the nozzles.
Abstract:
A pulsed droplet ink jet printer has at least one channel communicating with a nozzle. The side wall of the channel is formed as a shear mode piezo-electric actuator comprising an unpoled crystalline material. Electrodes applied to the actuator enable an electric field to be applied such that the actuator moves in transversely of the field to change the liquid pressure in the channel and thereby eject a droplet through the nozzle. The actuator can be made in two parts so as to deform, in cross section, to a chevron formation.
Abstract:
A pulsed droplet ink jet printer has at least one channel communicating with a nozzle. The side wall of the channel is formed as a shear mode piezo-electric actuator. Electrodes applied to the actuator enable an electric field to be applied such that the actuator moves in the direction of the field to change the liquid pressure in the channel and thereby eject a droplet through the nozzle. The actuator can be made in two parts so as to deform, in cross section, to a chevron formation.
Abstract:
A pulsed droplet ink jet printer has relatively long thin ink channels extending in parallel between an ink manifold 13, and a nozzle plate 5 providing a nozzle 6 for each channel. Side walls 11 may be formed substantially entirely of piezo-electric material so as to be displaceable transversely into a selected channel on the application of an electric field. This transverse displacement produces an acoustic wave in the channel which results in the ejection of an ink droplet. The side walls may deflect in shear mode to a cross-section of chevron formation. Usefully, it is arranged that both side walls adjoining the selected channel are displaced inwardly of the channel to cooperate in droplet ejection. Under this arrangement, the channels are assigned alternately to first and second groups of channels, only one group of channels being capable of actuation at any one instant. The nozzles associated with the respective groups of channels may be offset so as to compensate for the time delay in actuation of channels in the first and second groups.
Abstract:
A pulsed droplet ink jet printer has at least one channel communicating with a nozzle. The side wall of the channel is formed as a shear mode piezo-electric actuator. Electrodes applied to the actuator enable an electric field to be applied such that the actuator moves in the direction of the field to change the liquid pressure in the channel and thereby eject a droplet through the nozzle. The actuator can be made in two parts so as to deform, in cross section, to a chevron formation.
Abstract:
A method for folding demand printed webs into signatures for gathering by rotary gathering and binding machines, as well as the signatures produced thereby, are disclosed. The method involves the steps of digitally printing pages onto a moving web of material, creating a series of fan folds across the transverse axis of the web, severing the web after a desired number of fan folds have been created to form a separate log, and chop folding the resulting log zero one or more times to form a signature. The resulting signature includes a plurality of layers each having pages printed thereon in proper orientation and sequence and includes a sturdy closed backbone which enables the signature to be easily handled by conventional high-speed rotary gathering machines.