Patent Publication Number: US-2011057996-A1

Title: Printer Cartridge Having A Parasitic Power Circuit

Description:
This application claims priority to pending U.S. application Ser. No. 12/023,201 filed Jan. 30, 2008. This and all other extrinsic materials discussed herein are incorporated by reference in their entirety. Where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply. 
    
    
     FIELD OF THE INVENTION 
     The field of the invention is printer cartridge technologies. 
     BACKGROUND 
     Printer manufactures (e.g. HP™, Dell™, Lexmark™, Xerox™, etc. . . . ) design and develop printers that require specific printer cartridges using a medium delivery system designed for the printer. Several example medium delivery systems include thermal inkjets, piezoelectric inkjets, or continuous inkjets. Printers expect their corresponding cartridges to operate according to designed electrical characteristics or behaviors of the medium delivery system. For example, manufacturers of thermal inkjet printers have been the exclusive source of new (e.g. non-remanufactured) printer cartridges for their printer models with third party manufacturers only supplying re-manufactured (e.g. re-conditioned or re-filled) used printer cartridges. 
     Printer manufactures continue to design or produce new models of printers that require different cartridges than used in previous printer models. When one printer model becomes obsolete in favor of a newer model, OEMs that produce printer cartridges eventually stop manufacturing the cartridges for the older printer designs in favor of cartridges for newer printer models. Frequently, consumers find themselves in a position of owning an obsolete, yet functional printer. The consumer is forced to purchase a new printer simply because they are unable to purchase older model cartridges even though their older printer is still operable. 
     Ideally, consumers should be able to purchase cartridges for their functional printers long after their model of printer becomes obsolete. Unfortunately, third party manufacturers do not seek to produce such cartridges for several reasons. First, the third party must duplicate or reverse engineer older models of printer cartridges to determine how the medium delivery system operates. Such an undertaking can be quite cost prohibitive. Second, a third party cartridge has to match exactly the electrical characteristics or behaviors expected by the printer. Empirically discovering all the subtle interactions between the printer and cartridges is time consuming. Third, there could be substantial intellectual property barriers surrounding the medium delivery system to prevent the third party from producing reversed engineered cartridges. Therefore, third party manufactures avoid producing such printer cartridges. 
     Co-owned U.S. patent application 2006/0250667 (to Loyer et al.) addresses various aspects of creating a printer cartridge having a medium delivery system other than a medium delivery system expected by a printer. However, the application does not address how to adapt a non-OEM cartridge&#39;s electrical characteristics (e.g. impedance or power draw) or behaviors to match those expected by a printer. 
     What has yet to be appreciated is that non-OEM printer cartridges targeting various models of printers can be produced using alternative medium delivery systems while avoiding the issues stated above. An alternative medium delivery system will have different electrical characteristics or behaviors than those expected by the printer. However, a circuit can be included in the non-OEM cartridge that adapts the non-OEM cartridge&#39;s electrical characteristics or behaviors to match those expected by the printer. For example, the circuit can parasitically draw power from signal lines activated by the printer and use the power to operate the alternative medium delivery system while maintaining a proper load impedance or power draw on the active signal lines. 
     Thus, there is still a need for a non-OEM printer cartridge having an alternative medium delivery system other than a medium delivery system expected by a printer and where the printer accommodates the non-OEM cartridge when printing. 
     SUMMARY OF THE INVENTION 
     The present invention provides apparatus, systems and methods in which a non-OEM printer cartridge will be accommodated by a printer expecting an OEM cartridge. 
     One aspect of the inventive subject matter includes non-OEM printer cartridges having a medium delivery system other than a medium delivery system expected by the printer. Non-OEM cartridges preferably have a plurality of signal lines that are activated by the printer from which power is drawn to power the non-OEM cartridge&#39;s medium delivery system. A circuit within the non-OEM cartridge parasitically draws power from active signal lines while ensuring the printer observes expected impedances or expected power draws that are within the printer&#39;s tolerances. 
     Some embodiments of a non-OEM cartridge include an independent power source. The power source, preferably a battery, powers a circuit within the cartridge when there is insufficient power supplied by the printer via the active signal lines. The power source preferably supplies power only for a time period consistent with normal printing operations. One should note the power source is not required to power the cartridge when the printer is turned off or not printing. 
     Within the context of this document, “non-OEM printer cartridge” means a cartridge produced by a manufacture using a design other than the recommended design of the printer manufacturer. 
     The term “medium” means a material that can be deposited by a printer. Printable materials preferably comprise liquid inks or other pigmented substances. However, materials are also contemplated to include other substances beyond liquids. For example, mediums can also comprise solids including powders, plastics, or other material that can be deposited on a surface. 
     Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawings in which like numerals represent like components. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         FIG. 1  is a schematic of a printer cartridge. 
         FIG. 2  is a schematic of a printer cartridge&#39;s internal components. 
         FIG. 3  is a schematic of a circuit that parasitically draws power from signal lines activated by a printer. 
     
    
    
     DETAILED DESCRIPTION 
     In  FIG. 1  non-OEM printer cartridge  100  comprises contact pad  110  and print head  120  where non-OEM cartridge  100  is configured to replace an OEM cartridge. Although illustrated using a simple form, preferably cartridge  100  is sized and dimensioned to have substantially similar physical characteristics of the OEM cartridge it is designed to replace. Especially preferred versions of cartridge  100  ensure contact pad  110  and print head  120  are sized and dimensioned to correspond to those of the OEM cartridge to ensure a printer accommodates cartridge  100 . 
     One should note there are a substantial variety of cartridge models, each having different physical characteristics, all of which are contemplated. Physical characteristics can vary widely from manufacturer to manufacturer as well as within a manufacturer&#39;s own product line. For example, cartridges for the HP 842C printer model are physically different than the cartridges for the HP C5180c all-in-one printer model. 
     Contact pad  110  includes one or more of contacts  115  that are accessible by a printer (not shown). Pad  110  and contacts  115  are sized and dimensioned to substantially match the contacts found on the OEM cartridge and in the printer. Contacts  115  couple to the printer&#39;s cartridge interface and provide the printer access to the cartridge&#39;s signal lines including, address lines, power select lines, pen selects, grounds, communication channels, or other electrical connections used to communicate with cartridge  100 . A printer activates one or more of the signal lines via contacts  115 . At least some of contacts  115  preferably correspond to signal lines within cartridge  100 . 
     Print head  120  varies from embodiment to embodiment depending on which medium delivery system is employed by cartridge  100 . Preferably head  120  includes a plurality of nozzles  125  used to expel a medium from cartridge  100  onto a surface. Preferred nozzles are configured with an arrangement to print with a resolution of at least 600 dpi (dots per inch) and even more preferred embodiments have nozzle arrangements to provide printing at a resolution of at least 1200 dpi. 
     In  FIG. 2  non-OEM printer cartridge  200  is adapted to operate with printer  205 . Non-OEM printer cartridge comprises parasitic circuit  250 , medium delivery system  240  other than a medium delivery system expected by the printer, and optional battery  260 . By providing cartridge  200  having parasitic circuit  250 , printer  205  accommodates cartridge  200  as having an acceptable medium delivery system. 
     Ordinarily printer  205  activates one or more signal lines on an OEM printer cartridge to print a medium on a surface. For example, a printer that uses a thermal inkjet technology 
     During operation, printer  205  using an OEM cartridge monitors (e.g. through the signal lines) one or more electrical characteristics or behaviors of the OEM cartridge to ensure the cartridge is operating as expected. Electrical characteristics include power draw (e.g. current or voltage drop), impedance, capacitance, or other electrical properties. Behaviors include timing responses, return signals or information, protocol exchanges, or other operations. Some electrical characteristics and behaviors can be found in existing literature, while others are determined empirically. Example literature containing information relating to thermal inkjet technologies includes, U.S. Pat. No. 5,644,342 (to Argyres, 1995) that describes the addressing of heating resistors, U.S. Pat. No. 5,757,394 (to Gibson et al, 1995) that describes a print head circuit that identifies the specific print head, and U.S. Pat. No. 6,431,677 (to Anderson et al, 2000) that describes methods of driving a print head. 
     In a preferred embodiment, non-OEM cartridge  200  includes medium delivery system  240  that could have substantially different electrical properties or behaviors than those expected by printer  205 . For example, medium delivery system  240  preferably includes a piezoelectric element as a replacement for a thermoelectric element of a thermal inkjet system. A piezoelectric inkjet system utilizes a vibration element (e.g. a crystal) that flexes under a voltage difference to expel ink as opposed to using a heating element to boil the ink. A piezoelectric medium delivery system requires a different nozzle voltage to expel ink than required by a thermal inkjet delivery system. Piezoelectric delivery systems are also described elsewhere including U.S. Pat. No. 4,245,225 (to Fillmore et al, 1978) describing the use of a piezoelectric element to drive ink delivery, U.S. Pat. No. 5,757,396 (to Bruner, 1994) describing the use of ultrasonic vibrations caused by a piezoelectric actuator, and U.S. Pat. No. 6,701,593 (to Lin et al, 2001) describing production methods for piezoelectric print heads. 
     Cartridge  200  utilizes parasitic circuit  250  for several purposes. First, parasitic circuit  250  draws power from a signal line activated by printer  205  to power medium delivery system  240 . Second, parasitic circuit  250  adjusts the electrical characteristics or behaviors of medium delivery system  240  to substantially match the properties of an OEM cartridge. Although circuit  250  is shown as separated from delivery system  240 , one should note that circuit  250  can be easily incorporated into any suitable delivery system without departing from the scope of the inventive subject matter. 
     During operation, printer  205  could expect the electrical characteristics of signal lines  215  to vary over a large spectrum of values. Parasitic circuit  250  adaptively alters the electrical characteristics of signal lines  215  to meet the printer&#39;s expectations by responding to activity on signal lines  215 . 
     Printer  205  expects a load impedance on different signal lines  215  to vary over many orders of magnitude. For printers designed to use thermal inkjet technologies, signal line load impedances can range from a few Ohms to many kOhms or greater from one line to another. Parasitic circuit  250  adjusts the impedance on signal lines  215  to maintain the load impedance within the printer&#39;s impedance tolerances while the signal line is active. A preferred parasitic circuit maintains the signal line&#39;s load impedance within 40% of the load impedance expected by the printer. A more preferred circuit maintains the signal line&#39;s load impedance within 20% of the expected load impedance. A yet more preferred circuit maintains the signal line&#39;s load impedance within 5% of the expected load impedance. 
     Additionally, printer  205  expects the power draw on signal lines  215  to be within tolerances. Just as with impedance, printers that use thermal inkjet technology expect the cartridge to have varying power requirements during use. Within the scope of this document power draw is used euphemistically to describe the voltage on the line or drawn current as well as both combined (e.g. P=IV). Thermal inkjet printers provide 24 volts on a power select line, where newer printers provide 12 volts, and yet newer printers provide 3 volts. In a preferred embodiment, non-OEM cartridge  200  accommodates signals up to 4 volts on an active signal line, where more preferred embodiments accommodate up to 13 volts, and yet more preferred embodiments accommodate up to 25 volts without damaging the non-OEM cartridge or its components. 
     Typically, thermal inkjet printers have different expectations for address lines and for power select lines. For example, a specific printer model expects address lines to have a load impedance in the range from approximately 20 kOhms to approximately 50 kOhms when an address line is active with a voltage of approximately 12 to 23 volts, with a corresponding current draw of about 600 μA. Alternatively, the power select lines are expected to have a load impedance in the range from approximately 8 Ohms to approximately 84 Ohms when the power select line is active with a voltage of about 12 volts, with a corresponding current draw of about 140 mA to 330 mA. One should note the previous values are from a specific model of printer and can vary substantially from one medium delivery system technology to another and can also vary from manufacturer to another or even from one printer model to another. 
     Because medium delivery system  240  has different electrical requirements than an OEM delivery system, one of the responsibilities of circuit  250  is to convert current drawn from one or more of signal lines  215  into current acceptable to system  240 . In a preferred embodiment, circuit  250  is configured to supply system  240  an average current over a time period greater than the active time of the signal lines. In some embodiments, this is achieved through storing charge in a capacitor or an inductor as described below. In other embodiments, an independent power source can be included in cartridge  200  to supply additional power when signal lines  215  supply insufficient power. For example, optional battery  260  can be included to supply additional power needs. 
     Consider, for example, an embodiment where the printer expects an OEM cartridge using a thermal inkjet technology and where non-OEM cartridge  200  includes a medium delivery system  240  comprising a piezoelectric delivery system, or other system having a non-thermoelectric element. Signal lines  215  comprise at least one address line to select a heating element and at least one power select line to drive the heating element. Parasitic circuit  250  draws the bulk of its power from the power select line when it is activated by the printer. Circuit  250  drives the piezoelectric delivery system having a piezoelectric element as well as stores additional power, possibly in an inductor or capacitor. When the power select line becomes inactive, circuit  250  can continue to supply power (e.g. current or voltage) from its stored power. The power is then used to drive the piezoelectric delivery system through one or more of power lines  255  even when the power select line is not active. Especially preferred embodiments draw power from a signal line selected from at least five address lines or at least seven power select lines depending on the OEM cartridge that is being replaced. 
     As printer  205  interacts with cartridge  200  through signal lines  215 , it also expects cartridge  200  to accommodate signal timing under the control of the printer. For example, thermal inkjet printers provide signals on address lines for up to several μS and provide signals on power select lines from a few tens of nS to several μS. During such times, circuit  250  ensures that cartridge  200  does not generate unexpected signals on signal lines  215 . One should note that the timing behavior of signal lines  215  can also depend on printer make or model. 
     Additionally, printer  205  expects cartridge  200  to be responsive to communications over signal lines  215 . Preferred signal lines  215  communicate data (e.g. control information, ID information, status or other information) between the printer and cartridge  200  using a serial communication protocol. However, it is also contemplated that signal lines  215  could also transport data using a parallel communication protocol. 
     Preferably at least some of signal lines  215  are passed through to medium delivery system  240 . System  240  interprets the signals to determine how to operate print head  225 . It is also contemplated that circuit  250  could intercept some or all of signal lines  215  and supply delivery system  240  with necessary signals to control print head  225 . 
     In a preferred embodiment, print head  225  comprises a piezoelectric print head where the signal lines are used to address the nozzles of the print head. Print head  225  draws the medium from medium source  245 , preferably a liquid ink reservoir. Although medium source  245  is preferably within cartridge  200 , it is also contemplated that medium source  245  can include an external source relative to the cartridge. 
     In  FIG. 3  parasitic circuit  300  draws power from one or more of signal lines  315  and supplies power to a medium delivery system via one or more of power lines  355 . One skilled in the art will appreciate that parasitic circuit  300  represents one embodiment of many possible circuit embodiments that can be used to maintain electrical characteristics or behaviors within a printer&#39;s tolerances. Circuit  300  and other suitable circuits are described in co-owned U.S. pending patent application Ser. No. 11/246,728, titled “Diode Power Array”. 
     In some embodiments, a printer may require a more constant load impedance on signal lines  315 . Circuit  300  accommodates such signal lines by having resistor Rc and MOSFET Qr in series with rectification diode Ds and inductor La. It is understood that an optional impedance control circuit can be added for each signal line in use. 
     On initial power-up, bias resistor Rb allows the MOSFET Qr to conduct current when a signal line goes to the high state. Once storage capacitor Ca has sufficient voltage to enable the power supply circuit and the medium delivery system, the impedance control circuit will begin to operate. 
     Inductor La or Capacitor Ca store power while at least one of signal line  315  is active for use when the signal line is not active. Through suitable selection of the elements of circuit  300 , circuit  300  is then configured to supply an average current to the medium delivery system over a time period greater than an active period of the active signal line. 
     It is also contemplated that parasitic circuit  300  can optionally include a microprocessor (not shown) and memory (e.g. RAM, ROM, flash, or other data storage; not shown) that stores data or instructions for use by the microprocessor. When a signal line is active, the microprocessor monitors or communicates with the printer through signal lines  315  according to the printer&#39;s expected cartridge communication protocol. The microprocessor could then adjust the electrical characteristics or behaviors observed by the printer to ensure the printer does not reject the non-OEM cartridge. For example, a Digital Signal Processor (DSP) can be used as a signal converter that converts signals from the printer to signals that can drive the medium delivery system, or that converts return signals from the medium delivery system (e.g. ID information) into signals that would be accommodated by the printer. 
     It should be apparent to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refers to at least one of something selected from the group consisting of A, B, C . . . and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc.