Abstract: A print head assembly for a continuous ink jet printer has an ink heater module, including a valve assembly, which can be independently attached to or detached from the print head assembly. The print head assembly may also have an ink droplet generator module which is independently replaceable and may have other independently replaceable modules. Fluid pathways for in and solvent in the modules are preferably in the form of manifolds having fluid conduits defined between opposing faces of members of the modules. The modular print head assembly is easily repaired and maintained and the number of connectors prone to fluid leakage is minimized by the manifolds.

Abstract: A print head assembly includes a print head and a print head cover disposed around the print head. The print head cover includes a face and a print opening disposed in the face. The print opening disposed adjacent an ejection point of the print head. A perforated area is disposed on the face.

Abstract: A hollow cylindrical support for a plurality of flow-through inkjet print heads has two folded wall sections cooperating to define elongate inlet and outlet ink manifolds, one wall section being thermally conducting so as to promote heat transfer along the length of the support, the other wall section being thermally insulating so as to inhibit heat transfer between the inlet and outlet manifolds. The thermally insulating section serves to trap a boundary layer of fluid, for example in a cavity wall or cellular material.

Abstract: A method of manufacturing an ink jet print head includes the steps of bonding a body of piezoelectric material to a base plate and cutting channels into the piezoelectric material to form ink chambers which are actuated by applying voltages to electrodes provided on surfaces of the chambers. The base plate carries IC's which contain the drive circuitry for actuating the ink chambers. To ensure reliable electrical connection between the chamber electrodes and the IC's, the electrodes and conducting tracks on the base plate are formed in a single step by depositing a conductive layer over both the PZT body and the base plate. A step of masking or selective removal of material may be performed to achieve the necessary patterning of the electrodes and tracks.

Abstract: A hollow cylindrical support for a plurality of flow-through inkjet print heads has two folded wall sections cooperating to define elongate inlet and outlet ink manifolds, one wall section being thermally conducting so as to promote heat transfer along the length of the support, the other wall section being thermally insulating so as to inhibit heat transfer between the inlet and outlet manifolds. The thermally insulating section serves to trap a boundary layer of fluid, for example in a cavity wall or cellular material.

Abstract: Droplet deposition apparatus comprises a fluid chamber comprising an actuator actuable by electrical signals to effect ejection of droplets from the fluid chamber, a drive circuit for supplying the electrical signals; and a conduit for supplying droplet fluid to said fluid chamber, the drive circuit being in substantial thermal contact with the conduit so as to transfer a substantial part of the heat generated in the drive circuit to the droplet fluid.

Abstract: A nozzle plate includes a body and an insert formed of polymeric material. Each nozzle has an inlet, an outlet, and a bore extending between the inlet and the outlet and formed through the polymeric material of the insert located within an aperture formed in a body of the nozzle plate.

Abstract: A component for a drop-on-demand piezoelectric printhead is formed from a block of piezoelectric material and a substrate. The block of piezoelectric material has grooves formed in its lower surface and is attached to the substrate using an adhesive that is applied in sufficient quantity such that adhesive enters the grooves cut into the piezoelectric material. Upper grooves are sawn into the piezoelectric material through to the glue-filled lower channels in order to form ejection channels, the walls of which are separated from one another by means of a glue fillet.

Abstract: A piezoelectric printhead or other droplet deposition apparatus has parallel liquid containing channels defined by a base and displaceable walls, and covered by a cover number. The channels each have at least one nozzle for ejecting droplets. Each nozzle may be disposed in the base, the cover then having two ink supply parts spaced lengthwise of each channel on opposite sides of the nozzle. Alternatively two longitudinally spaced nozzles may be provided in the base of each channel. The cover may have a conductive track corrected to wall-displacing electrodes, the points of connection being outside the channels.

Abstract: A component for a drop-on-demand piezoelectric printhead is formed from a block of piezoelectric material and a substrate. The block of piezoelectric material has grooves formed in its lower surface and is attached to the substrate using an adhesive that is applied in sufficient quantity such that adhesive enters the grooves cut into the piezoelectric material. Upper grooves are sawn into the piezoelectric material through to the glue-filled lower channels in order to form ejection channels, the walls of which are separated from one another by means of a glue fillet.

Abstract: An ink jet printhead has a body of PZT bonded to a base plate. Channels cut in the PZT form ink chambers which are actuated by applying voltages to electrodes on surfaces of the chambers. The base plate also carries IC's which contain the drive circuitry for actuating the ink chambers. To ensure reliable electrical interconnection between the chamber electrodes and the IC's, the electrodes and conducting tracks on the base plate are formed in a single step by depositing a conductive layer over both the PZT body and the base plate. The necessary pattern of electrodes and tracks can be achieved by masking or by selective material of conductive material.