Abstract: Bidirectional communications between a host computer and a printer connected to the host, either locally or by way of a network, are used to provide a user of the host with access to a substantially real-time, visual and functional replica of the operator panel of the printer. The user may view the replica to access all data available through the printer operator panel. Using a mouse or other input device, the user of the host computer can also effectively actuate any pushbuttons or other operator panel control devices depicted as part of the replica.

Abstract: A printer having a disposable print head which contains a consumable ink supply includes the capability of determining the level of ink in the print head without directly measuring the ink supply. The print head includes a number of resistors which can be driven to an open circuit condition by the printer. The printer includes a counter and memory for tracking the usage of the print head and a driver for selectively driving the print head resistors to an open circuit condition based upon such usage. The printer is also capable of detecting the condition of the resistors on the print head and producing a resultant visual display.

Abstract: A serial drop-on-demand ink jet printer having an ink cartridge mounted for reciprocation on a carrier which traverses paper advancing through the printer. The cartridge includes a nozzle array for the ejection of ink droplets onto the paper, and the carrier includes a tab upstream from the nozzle array, in the direction of paper travel, which touches the top surface of the paper and sets the printhead-to-paper gap. The paper is pushed against the tab and maintains a minimum gap to prevent paper from coming into contact with the nozzle array. The paper is urged against the tab into the proper position relative to the nozzle array by a deflectable guide which acts on the back surface of the paper.

Abstract: A computer and printer system in which communication between the computer and printer can be carried out in either a bidirectional mode or a unidirectional mode. As disclosed, the computer operates in a single-threaded multi-tasking environment in which a printer control utility application runs to facilitate bidirectional communication with an attached printer. The application program maintains the computer parallel port in a bidirectional communication and printing mode, but is capable of taking the parallel port out of this mode in order to perform unidirectional printing, either from another application operating in the multi-tasking environment or from a DOS session running in the environment. The printer control utility prevents the mixing of unidirectional and bidirectional print jobs through the parallel port.

Abstract: A maintenance station for maintaining either a monochrome or a multi-color printhead in an ink-jet printer includes a single flexible wiper having a first wiping edge for wiping the ink-jet nozzle surface of a monochrome printhead and a plurality of second wiping edges for wiping the ink-jet nozzle surface of a multi-color printhead. Wiping of a monochrome printhead is accomplished by moving the printhead to one side of the wiper, raising the wiper into the path of travel of the nozzle surface, and moving the printhead past the wiper. Wiping of a multi-color printhead is accomplished in a similar manner but the printhead is first positioned on the opposite side of the wiper. The flexibility of the wiper is chosen to apply an optimum wiping force to a multi-color printhead as the printhead is moved past the wiper. A backstop is provided at one side of the wiper to brace it against deflection, so that the wiper applies a greater wiping force to a monochrome printhead than it does to a multi-color printhead.

Abstract: A wiper for an ink jet printhead comprises a monolithic body having a mounting portion and a head portion, the head portion including a wiper portion and a beam portion for supporting the wiper portion on the mounting portion. The mounting portion has a bottom surface and a slot centered in the bottom surface where the slot extends toward the head portion from the bottom surface and receives a mounting beam that is movable. The wiper is characterized in that the wiper portion has two non-parallel side surfaces which diverge from the beam portion and intersect a flat top surface of the wiper portion at acute angles so as to form two parallel wiping edges which may alternately wipe the printhead as the printhead moves back and forth relative to the wiper. Because the side surfaces of the head portion form angles of less than 90.degree. with the top surface there is less tendency for the head to trap and ride on ink wiped from the printhead.

Abstract: An ink-jet printer cartridge having a center reservoir chamber and two side reservoir chambers for holding inks of three different colors is provided with ink flow pathways of special configuration for connecting the reservoir chambers to exit ports at the print element. The ink flow pathways are provided with ridges extending along substantially their entire lengths so that air bubbles cannot completely block ink flow through the pathways. The ink flow pathways are disposed such that they have a vertical component of direction over their entire length and the pathways connecting the side reservoir chambers to exit ports include duct portions disposed at compound angles relative to the axes of the cartridge so that air bubbles, because of their buoyancy, will naturally tend to drift upwardly through the inclined ducts toward the reservoir chambers during normal usage, or drift toward the exit openings when the cartridge is inverted for priming.

Abstract: Multiple host computers on a network are connected through an interface, or network adapter, to a printer having a printer controller capable of bi-directional communication with the computers on the network. The interface communicates with the network computers in a manner to present a different virtual printer to each host computer. The interface maintains a data set for each host computer which includes designations of the types of printer status information of interest to that host. The interface is capable of communicating with the printer controller to obtain a range of printer status information, and the interface communicates with each host computer to present printer status information of interest to that computer based upon that computer's data set. In the disclosed form of the invention, the interface notifies each interested host computer concerning types of printer status information to which changes have occurred; and the host computers communicate requests for more detailed information.

Abstract: An ink jet printer cartridge assembly including a cartridge body with at least one ink chamber from which ink flows to a print head. A standpipe in the ink chamber includes an opening therethrough for the flow of ink to the print head, and a filter cap is secured on the top of the standpipe to limit the introduction of air bubbles and particulate matter in the flow of ink toward the print head. The filter cap includes a mesh material formed into a dome-shaped configuration and an elastomeric material molded about the periphery of the mesh portion, with the elastomeric material being received around the top portion of the standpipe.

Abstract: A print quality enhancement arrangement for a dot matrix printer such as a thermal ink jet printer. The arrangement includes a buffer for receiving 300 dots per inch (dpi) resolution data in the horizontal (print head movement) direction and creates 600 dpi resolution data using image enhancement techniques. The arrangement further includes correction of the higher resolution data to remove pels which are unprintable due to the frequency response of the print elements in the print head. The correction is performed using knowledge of the history of printed pels and the original 300 dpi data. The creation of the higher resolution data and its correction occur "on-the-fly" as data is being fed to the print head, rather than through the creation of a 300 by 600 dpi bitmap.

Abstract: A method and apparatus for inserting a compressed foam block into a generally rectangular ink jet print head ink chamber. The foam is compressed in an insertion tool which includes a compression area and compression fingers extending therefrom. A block of foam is placed in the principal area of the insertion tool and compressed in two dimensions, following which the ink jet print head is positioned around the compression fingers. The foam is pushed from the principal part of the insertion tool into the area surrounded by the compression fingers inside the print head ink chamber, and the force applied to the foam is continued. At a certain force level, the cartridge is allowed to move, under the force applied to the foam, off of the insertion fingers, leaving the foam inside the cartridge.