Abstract:
A method and apparatus for refurbishing used ink jet cartridges. The apparatus utilizes an interchangeable cradle attachment arrangement that can hold virtually any type of ink jet cartridge. After the ink jet cartridge is placed in an ink jet cartridge cradle, a vacuum is applied to the print head of the cartridge to drain any excess ink. After draining excess ink, the ink jet cartridge can be replenished using the fill gun that is included in the ink jet cartridge refurbishing system.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     This application is a continuation of U.S. patent application Ser. No. 10/875,463 filed Jun. 24, 2004, and entitled APPARATUS AND METHOD FOR REFURBISHING USED CARTRIDGES FOR INK JET TYPE IMAGING DEVICES. Applicants claim the benefit of this prior applications under 35 U.S.C. §120. The prior application is incorporated herein by reference. A Power of Attorney and Change of Correspondence Address Indication form was filed on Jan. 5, 2006. 
     
    
     TECHNICAL FIELD OF THE INVENTION  
       [0002]     The invention is directed to the refurbishment of ink jet cartridges used in ink jet type imaging devices such as printers, photocopiers, and facsimile machines, for example. The invention encompasses both devices and methods for refurbishing used ink jet cartridges.  
       BACKGROUND OF THE INVENTION  
       [0003]     Ink jet imaging devices produce text and images on a substrate, such as paper, by ejecting minute quantities of ink from a reservoir onto the substrate in response to electrical commands. The electrical commands activate small orifices or ink jets in a print head to eject the ink in the desired locations to form the desired images. Because the ink in an ink jet imaging device is used up eventually in the printing process, conventional ink jet imaging devices include the ink reservoir in a replaceable cartridge commonly referred to as an ink jet cartridge. The print head containing the orifices through which the ink is ejected is also commonly included in the replaceable ink jet cartridge. The remainder of the ink jet imaging device includes electrical control components and mechanical components for moving the ink jet cartridge with respect to the printing substrate (paper) and for moving the substrate with respect to the ink jet cartridge.  
         [0004]     Photocopiers, printers, plotters, and facsimile machines are examples of devices that may utilize an ink jet printing or imaging process. As used in this disclosure “ink jet device” encompasses any type of device using an ink jet process. Also, for purposes of the following description, the portion of the ink jet device other than the ink jet cartridge will be referred to herein simply as an ink jet device whether or not the ink jet cartridge is installed. The portion of the ink jet device that carries the consumable ink for the ink jet imaging process will be referred to as an ink jet cartridge, or simply cartridge, regardless of the particular design and regardless of the other components included on the ink jet device such as a print head and associated electrical lines and contacts.  
         [0005]      FIG. 1  is a view in perspective of a typical prior art ink jet cartridge  100 . Ink jet cartridge  100  includes a container  101  adapted to contain a supply of ink (the ink not being shown in the figure). The bulk of container  101  is generally rectangular in shape with a lower portion  102  projecting from the rest of the container. Print head assembly  104  is located on lower portion  102  of container  101  and includes a large number of minute, electrically stimulated orifices or ink jets  105  through which ink from container  101  is ejected in the printing process. It will be appreciated that the orifices or ink jets are shown diagrammatically in  FIG. 1  in an exaggerated scale, and that the orifices are in fact very small in order to produce the desired image resolution. The commands or electrical stimuli required to operate the orifices or ink jets  105  are applied to print head assembly  104  through electrical conductors  106  which terminate at contact pads  107  on a side of container  101 . An ink jet device in which cartridge  100  is to be used will include a corresponding set of electrical contacts exposed so as to make contact with contact pads  107  on the cartridge. The electrical signals required for operating print head assembly  104  originate from a print control system (not shown) included in the ink jet device. The illustrated prior art ink jet cartridge  100  also includes additional orifices facilitating fluid communication to ink container  101 . The first additional orifice comprises an opening  109  commonly referred to as a vent opening or vent hole. The second additional orifice comprises an opening which is commonly referred to as a maze opening or maze hole located on the surface of cartridge  100  indicated by arrow  110 . The maze hole is associated with a ball that functions as a check valve to prevent the flow of material out of container  101 .  
         [0006]     Due to space limitations and other physical restrictions in ink jet devices, ink jet cartridges typically have a relatively limited supply of ink for use in the ink jet printing process. The working life of the print head assembly of an ink jet cartridge is, in fact, commonly much greater than the working life of the ink supply in the cartridge. Thus, although original equipment manufacturers may prefer for ink jet device users to use totally new ink jet cartridges due to the relatively high profit margins associated with selling new ink jet cartridges, it is commonly possible to refurbish and reuse ink jet cartridges many times before they are no longer serviceable. Due to the popularity and low cost of ink jet devices, the sale of both new and used ink jet print cartridges has become a very big business.  
       SUMMARY OF THE INVENTION  
       [0007]     The present invention includes a method and apparatus for refurbishing used ink jet cartridges. The apparatus of the invention utilizes an interchangeable cradle attachment arrangement that can hold virtually any type of ink jet cartridge. After the ink jet cartridge is placed in an ink jet cartridge cradle, a vacuum is applied to the print head of the cartridge to drain any excess ink. After draining excess ink, the ink jet cartridge can be replenished using the fill gun that is included in the ink jet cartridge refurbishing system.  
         [0008]     The cradle attachment arrangement of the ink jet cartridge refurbishing system includes a first component that is secured to a supporting surface and has a receiving slot that is open on the top receiving end and closed on the bottom end by a support member. The second component of the cradle attachment arrangement includes a flange that is substantially the same shape as the receiving slot of the first component. The second component is connected to an ink jet cartridge cradle that holds the ink jet cartridge selected to be refurbished. The flange from the second component can be positioned alternatively in an attached position inside the receiving slot and a detached position outside of the receiving slot. Each ink jet cartridge cradle may include a vacuum sealing element that connects to a vacuum line. The vacuum applied through the vacuum line is used to help draw any remaining ink out of the ink jet cartridge while the cradle is positioned with the flange in the attached position.  
         [0009]     The cradle attachment arrangement may be used at one or more stations included in the ink jet cartridge refurbishing system for servicing ink jet cartridges. For example, the system may include an ink recovery station that serves only to draw ink out of the used ink jet cartridges using a vacuum source as described above. In addition, the system may include a clean/fill station. Either of these types of stations may employ a cradle attachment arrangement as described above.  
         [0010]     The clean/fill station utilizes a specialized ink jet cartridge cradle that includes a fixed component and a sliding component that moves vertically to allow loading and unloading an ink jet cartridge. The sliding component includes a maze vacuum sealing element associated with the cartridge maze hole and the fixed component includes a print head sealing element associated with the cartridge print head and an ink fill sealing element associated with an ink fill tube. The vacuum sealing element and print head cartridge sealing element are each connected to a vacuum source through respective tubes. The vacuum applied at the maze hole closes the valve in the cartridge at that location during the operation of the clean/fill station and the vacuum applied at the print head assembly draws ink through the ink fill tube and into the reservoir to re-fill the cartridge with ink.  
         [0011]     An additional component of the present invention is an ink pump assembly that includes an ink intake, ink outlet, and a control input. The ink pump assembly sends ink through an ink supply line to a fill gun that uses a fill needle that may be positioned to direct ink into an empty ink jet cartridge. The fill gun also includes a handle that is connected to the fill needle. A fill trigger switch or start switch is also preferably located on the handle. The fill trigger switch applies a control signal to the control input that causes the pump motor to activate the pump assembly and begin sending ink to the fill gun. Ink flows to the fill gun and into the ink jet cartridge through the properly positioned fill needle until a timer removes the control signal from the control input after a specified period of operation has elapsed. The flow of ink can also be stopped by a kill switch located on the fill gun that, when activated, produces a signal that is applied to turn off the ink pump. Once the ink jet cartridge has been re-filled with ink, air bubbles that may have formed in the ink may be removed from the cartridge by applying a vacuum at the vacuum sealing element of the recovery station.  
         [0012]     The ink pump assembly can be mounted in the interior of a housing that is also included in the ink jet cartridge refurbishing system of the present invention. The housing may also provide a supporting surface for one or more cradle attachment arrangements described above and for a fill gun holster that holds the fill gun when not in use. The fill gun holster also may serve to collect any excess ink flowing from the fill needle when the fill gun is in a holstered position.  
         [0013]     These and other objects, advantages, and features of the invention will be apparent from the following description of the preferred embodiments, considered along with the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]      FIG. 1  is a view in perspective of a prior art ink jet cartridge of a type that may be refurbished according to the present invention.  
         [0015]      FIG. 2  is a partially diagrammatic front view of an ink jet cartridge refurbishing system embodying the principles of the present invention.  
         [0016]      FIG. 3  is a diagrammatic representation of the ink jet cartridge refurbishing system shown in  FIG. 2 .  
         [0017]      FIG. 4  is a view in longitudinal section of a recovery cradle used in the system shown in  FIG. 2 .  
         [0018]      FIG. 5  is a partially cut away side view of an ink jet cartridge clean and fill cradle used in the refurbishing system shown in  FIG. 2 .  
         [0019]      FIG. 6  is a side view showing a preferred cradle attachment arrangement that may be used for one or more cradles in the refurbishing system shown in  FIG. 2 .  
         [0020]      FIG. 7  is a side view of a first component of the cradle attachment arrangement.  
         [0021]      FIG. 8  is a top view of the first component of the cradle attachment arrangement.  
         [0022]      FIG. 9  is a front view of the first component of the cradle attachment arrangement.  
         [0023]      FIG. 10  is a side view of a second component of the cradle attachment arrangement.  
         [0024]      FIG. 11  is a top view of the second component of the cradle attachment arrangement.  
         [0025]      FIG. 12  is an exploded side view of the ink jet cartridge cradle and cradle attachment arrangement shown in  FIG. 6 .  
         [0026]      FIG. 13  is a mostly diagrammatic representation of the ink jet cartridge fill gun included in the ink jet cartridge refurbishing system shown in  FIG. 2 . 
     
    
     DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0027]      FIGS. 2 and 3  illustrate an ink jet cartridge refurbishing system  200  embodying the principles of the invention, while  FIGS. 4 through 13  illustrate various components of the system. Referring first to the overall system view in  FIG. 2 , ink jet cartridge refurbishing system  200  embodying the principles of the invention generally includes a housing shown at reference numeral  201 . A lateral side  216  of housing  201  provides a support surface for a receptacle or fill gun holster  211  used to hold an ink jet cartridge filling gun or fill gun  210 . The opposite lateral side  216  of housing  201  provides a location for pressure regulator  213  and a vacuum application tool  214 . Pressure regulator  213  regulates air pressure to the various components of the system  200  that require air pressure for operation. In the alternative, pressure regulator  213  may be located in the interior of housing  201  as described in more detail with respect to  FIG. 3 .  
         [0028]     Front panel  202  of housing  201  includes two different stations for performing refurbishing operations on ink jet cartridges. The illustrated form of the invention includes a cradle attachment arrangement shown at reference numeral  208 , which can function as a recovery station for a variety of ink jet cartridges or a pressure equalization station, and a separate clean/fill station shown at reference numeral  205 . Each of these stations operate using at least one vacuum connection. The required vacuum is supplied from a respective vacuum fitting  206 ,  207 , or  209  in front panel  202  through a respective vacuum hose  218 ,  219 , or  220 . As will be discussed below with reference to  FIG. 5 , clean/fill station  205  uses two separate connections and an ink supply connection. The required vacuum is created in each instance with a venturi effect device as will be discussed further below with reference to  FIG. 3  although any suitable vacuum source may be used within the scope of the invention. While multiple external vacuum sources may be may be utilized, in a preferred embodiment a single source of external air is directed to regulator  303  which in turn creates a vacuum using a venturi effect as described herein resulting in first vacuum source  303 A. Regulator  303  then directs the vacuum through conduit  305  to control valve  307  which in turn provides a second vacuum source  219 A and third vacuum source  220 A through outlet tubes  308  and  309  to vacuum tubes  311 . Vacuum tubes  311  extend to a respective one of the vacuum fittings  206 ,  207  or  209  mounted on front panel  202  which in turn are connected to vacuum supplied tubes  219  and  220  as described in front in ¶38.  
         [0029]     Interchangeable cradle attachment arrangement  208  and fill gun  210  included in system  200 , allow the system to refurbish substantially any type of ink jet cartridge. The specific refurbishment process varies from one cartridge to another, however, the system is designed to accommodate each process step. In some cartridges, it is necessary or desirable to completely remove any ink remaining in the cartridge or the remnants of any cleaning material that may have been injected in the cartridge. Ink or other liquid remnant removal may be accomplished in a cartridge by using cradle attachment arrangement  208  as a recovery station adapted for the particular cartridge. The cartridge is inserted into a cradle associated with cradle attachment arrangement  208  and then a vacuum is applied to withdraw the desired fluid from the cartridge. Other types of cartridges require a vacuum to be applied at a particular top opening in order to equalize the pressure in the cartridge and allow it to function properly. This pressure equalization may be accomplished using a pressure equalization cradle with cradle attachment arrangement  208 . Still other types of cartridges may be cleaned and filled in a single step in system  200  using clean/fill station  205  as will be described below.  
         [0030]     In order to allow system  200  to refurbish substantially any type of ink jet cartridge, the system includes a second type of ink jet cartridge filling arrangement in addition to the clean/fill station  205  mounted on front panel  202 . This second type of ink jet cartridge filling arrangement includes fill gun  210  connected to a supply of ink located within housing  201  and described in more detail and illustrated with respect to  FIG. 3 . It should be noted that fill gun  210  is preferably connected to a supply of black ink, but may be connected to a supply of any color ink to allow for the refurbishment of color ink jet cartridges. Fill gun holster  211  mounted on lateral side  216  is preferably tilted downwardly and includes an overflow conduit  217  connected at its lowermost end to collect any overflow ink and direct it to the recovered ink reservoir. As will be described in detail below with reference to  FIGS. 3 and 13 , fill gun  210  is adapted to measure a desired amount of ink into an ink jet cartridge to refill the depleted ink jet cartridge.  
         [0031]     Front panel  202  includes a number of switch actuators for controlling a switch mounted in housing  201  behind front panel  202 . Vacuum control actuator  212  controls the position of the vacuum control switches. These switches will all be illustrated and described in connection with  FIG. 3 . Also visible in  FIG. 2  is fill gun switch actuator  203  and timer actuator  204  for controlling operation of fill gun  210 .  
         [0032]      FIG. 3  provides a diagrammatic representation of the various internal components of ink jet cartridge refurbishing system  200  including the internal components associated with fill gun  210  and the internal components associated with stations  205  and  208  mounted on front panel  202 . All of the vacuum operated portion of system  200  may be described with reference to mainly the right half of  FIG. 3  and the fill gun related components are shown to the left side of the figure.  
         [0033]     Referring first to the vacuum operated portion of system  200  in the right half of  FIG. 3 , air supplied from an external source fitting  304  through conduit or hose  326  is used to produce the required vacuum by venturi effect in the illustrated preferred form of the invention. This external source may be a large volume source (first vacuum source  303 ( a )) that is capable of providing sufficient volume at the desired pressure to simultaneously operate substantially all of the air pressure driven components in system  200 . Hose  326  preferably terminates in an appropriate fitting  329  associated with pressure regulator  303 , which also transmits vacuum from first vacuum source  303 ( a ).  
         [0034]     Pressure regulator  303  regulates the supplied air at the desired constant pressure for operating the various vacuum generating venturi devices described below. Various conduits distribute the regulated pressurized air to the venturi devices, known as vacuum ejectors, and any control valves associated with those devices. One conduit  300  runs to a vacuum ejector  301 . The vacuum tube  302  extending from vacuum ejector  301  provides a vacuum for vacuum application tool  214 . Another conduit  305  is provided for the stations in system  200  requiring a vacuum source. The distal end of conduit  305  is connected to control valve  307  which is operated by vacuum control actuator  212  mounted on front panel  202  as shown especially in  FIG. 2 . Control valve  307  is adapted to alternatively block the flow of air to its respective two outlet tubes  308  and  309  or to direct air to either one of the associated outlets. No control valve is shown as being associated with conduit  300  for supplying air to operate vacuum application tool  214 , however, other forms of the invention may include a suitable valve for enabling or disabling vacuum application tool  214 .  
         [0035]     Each outlet tube  308  and  309  is associated with a respective vacuum ejector  310 . Each vacuum ejector creates a vacuum at vacuum tubes  311  as the pressurized air flows straight through the ejector from the respective outlet tube to a respective exhaust tube  312 . Thus, when control valve  307  is switched to allow air to flow through a particular outlet tube  308  or  309 , the air passing through the main path of the respective vacuum ejector  310  creates the desired vacuum. Each vacuum tube  311  extends to a respective one of the vacuum fittings  206 ,  207 , or  209  mounted on front panel  202  (shown in  FIG. 2 ). Each exhaust tube  312  extends to the recovered ink reservoir  327  included in system  200 .  
         [0036]     Referring now to the left side of  FIG. 3 , control unit  328  is provided for fill gun  210  shown in  FIG. 2 . Control unit  328  includes an ink pump assembly  313  driven by a motor  314  through a control input  317 . Pump  313  receives ink from ink supply  316  at ink intake  315 , and directs ink through ink outlet  330  to ink supply line  318  that terminates in a suitable fitting  324  on an external surface of housing  201 . In the illustrated form of the invention fitting  324  is mounted on the same lateral side  216  of housing  201  as fill gun  210  (shown in  FIG. 2 ). Control input  317  for pump motor  314  includes a number of electrical control lines that extend to switches mounted on fill gun  210  as will be described further below with reference to  FIG. 13 .  FIG. 3  shows a separate control line  319  for a kill switch and another control line  320  for a fill gun start switch. In the preferred form of the invention, the electrical control lines extend from control input  317  to a suitable fitting  323  on an external surface of housing  201 . A suitable electrical control line connects to fitting  323  and extends to fill gun  210  as will be described below with reference to  FIG. 13 .  FIG. 3  also shows that control input  317  is associated with timer  321  and power switch  322 , which is connected to an external power supply through external power supply connector  325  for driving pump motor  314 . As will be described further below, timer  321  is used to control pump  313  to supply a desired volume of ink to fill an ink jet cartridge being refurbished.  
         [0037]      FIG. 4  shows a recovery station at cradle attachment arrangement  208  included on front panel  202  of refurbishing system  200 . In this illustrated embodiment of cradle attachment arrangement  208 , the recovery station includes a fitting or receiver referred to as an ink jet cartridge cradle, or simply cradle,  401  that is adapted to receive a particular type or style of ink jet cartridge. Cradle  401  snugly receives the particular type of ink jet cartridge (not shown in  FIG. 4 ) with a desired component on the cartridge, normally the print head, aligning with a vacuum scaling element  402  on an inner surface of the cradle  401 . Vacuum sealing element  402  is associated with an opening  403  in the cradle and a fitting  404  to which a connecting vacuum hose  218  (also shown in  FIG. 2 ) may be connected. It will be appreciated that each cradle is specifically adapted for a particular type of ink jet cartridge. It should also be noted that when vacuum sealing element  402  is adapted to seal against a print head, the sealing element preferably overlaps with a peripheral portion of the plate commonly associated with a print head so that the vacuum is not allowed to pull the print head plate from its position on the ink jet cartridge.  
         [0038]      FIG. 5  shows ink jet cartridge clean and fill cradle or clean/fill cradle  501  associated with the clean/fill station  205  shown in  FIG. 2 . This particular station is adapted to clean and fill a popular type of ink jet cartridge using a particular cleaning and filling technique. Clean/fill cradle  501  includes a fixed component  502  and a sliding component  503 . Sliding component  503  is adapted to slide up and down with respect to fixed component  502  as indicted by arrow  504 . In an upper position, sliding component  503  presses an ink jet cartridge (not shown) received in clean/fill cradle  501  against an upper part of fixed component  502  to provide seals against two upper sealing elements  505  and  506 . A seal is also produced in a resilient material  507  lining the upper surface of sliding component  503 . A vacuum is required at two different points in clean/fill cradle  501 . Thus, it will be noticed in  FIG. 3  that control valve  307  directs air through the two separate vacuum ejectors  310  associated with outlet tube  309 . The vacuum from one ejector is applied through tube  219  to sliding component  503  of clean/fill cradle  501  through tube  220 . Clean/Fill cradle  501  is also connected to an ink full tube  512  which ultimately extends to ink supply  316  (shown in  FIG. 3 ). In the particular type of ink jet cartridge with which clean/fill cradle  501  is adapted to be used, the used cartridge is placed in the cradle so that ink fill tube  512  and ink fill sealing element  505  align with a vent opening ( 109  in  FIG. 1 ), the upper vacuum supply tube  220  and cartridge print head sealing element  506  align with the print head ( 104  in  FIG. 1 ) of the cartridge, and the lower vacuum supply line  219  applies a vacuum to the maze opening ( 110  in  FIG. 1 ) of the cartridge. Each is supplied with vacuum by respective second vacuum source  220 A and third vacuum source  219 A, which, in a preferred embodiment originate from first vacuum source  303 A which divides the vacuum into second vacuum source  219 A and third vacuum source  220 A. The vacuum applied to maze opening  110  ensures that the valve associated with the maze opening stays closed while the vacuum applied through print head  104 .  
         [0039]     Referring now to  FIG. 6 , the preferred cradle attachment arrangement  208  allows the respective cradle to be removed and replaced with a different cradle as necessary to accommodate different types of ink jet cartridges. The preferred cradle attachment arrangement  208  includes a receiving feature or first component  602  which is adapted to be attached to front panel  202  at a suitable location. First component  602  is shown particularly in  FIGS. 7 through 9 . An attachment feature or second component  603  of cradle attachment arrangement  208  is adapted to be connected to a back surface of the respective cradle  610  and cooperates with first component  602  to produce a secure but easily releasable attachment between cradle  610  and front panel  202 . This second component  603  is illustrated particularly in  FIGS. 10 and 11 . In an alternative embodiment, the positions of the two components of cradle attachment arrangement  208  are reversed, so that the receiving feature is connected to the back surface of cradle  610  and the attachment feature is secured to front panel  202 .  
         [0040]     As shown in  FIGS. 7 through 9 , first component  602  of cradle attachment arrangement  208  includes a block of material having a receiving slot  605  (shown in  FIG. 8 ) formed therein. Receiving slot  605  includes a top opening  606  and terminates at the opposite end of first component  602  with a support member  607 . It will be noted particularly from the top view of  FIG. 8  that receiving slot  605  includes generally a T-shaped cross-section.  FIG. 9  shows that the base of the T-shape comprises a front opening  609 . Although any suitable connector may be used, in the preferred form of the invention first component  602  is connected to front panel  202  with bolts and thus includes bolt holes  608  through which the connecting bolts may extend.  
         [0041]     Referring now to  FIGS. 10 and 11 , second component  603  of cradle attachment arrangement  208  includes an elongated member having a generally T-shaped transverse shape as shown best in  FIG. 11 . This T-shape corresponds generally to the transverse shape of receiving slot  605  as shown in  FIG. 8 . Second component  603  is adapted to be bolted to cradle  610  (shown in  FIG. 6 ) and thus also includes bolt holes  612 , although the invention is not limited by the manner in which second component  603  is connected to the cradle. In fact, the cradle and second component may be integrally formed.  
         [0042]      FIG. 12  shows first component  602  secured in an appropriate position on front panel  202  and second component  603  secured to the back surface of cradle  610 . The cradle may be secured to panel  202  by first positioning cradle  610  and attached second component  603  above first component  602  as shown in  FIG. 12 . From this point, the cradle and second component  603  may be moved along a line indicated by arrow  1201 . Eventually the T-shaped second component  603  slides into the correspondingly shaped slot  605  (shown in  FIG. 8 ) until the components reach the position shown in  FIG. 6 . In this first or attached position, cradle  610  is securely attached to front panel  202  and may receive an ink jet cartridge for a desired refurbishment operation. However, cradle  610  may be removed easily to a second or detached position by simply sliding it upwardly in a direction opposite to that indicated by arrow  1201  until the T-shaped second component  603  clears slot  605 . Another different cradle with the same type of second component connected thereto may then be slid into first component  602  to accept a different type of ink jet cartridge as necessary.  
         [0043]      FIG. 13  shows a somewhat diagrammatic representation of fill gun  210  described above in  FIG. 2 . Fill gun  210  includes a handle or pistol-type grip  1301  and a fill needle  1302 . The fill gun also includes a fitting  1303  for making a connection with an ink supply line/electrical control line  1307 . An ink conduit  1304  extends from fitting  1303  to a proximal end of fill needle  1302 . Preferably a suitable check valve  1305  is included in conduit  1304  to prevent ink from flowing back in the direction from the fill gun to ink supply line/control line  1307 . Fill gun  210  also includes two switches, a start switch or fill trigger switch  1309  and a kill switch  1310 . Fill trigger switch  1309  is activated through a trigger actuator  1311 , while kill switch  1310  is activated through a separate button actuator  1312 .  
         [0044]     The operation of fill gun  210  may now be described with reference to  FIGS. 13 and 3 . In order to fill an empty ink jet cartridge with fill gun  210 , the user first withdraws fill gun  210  from fill gun holster  211  on system  200  and inserts the distal end of the needle  1302  into an orifice on the particular ink jet cartridge. The user also sets timer  321  associated with fill gun  210  to run pump  313  for a particular amount of time. Since pump  313  runs at a known speed and moves a known volume of ink in any given time, setting timer  321  has the effect of setting the volume of ink to be supplied to the cartridge. Once timer  321  is set and fill needle  1302  is appropriately placed in the empty cartridge, the user depresses trigger actuator  1311  to trip the fill trigger switch  1309 . Control input  317  associated with pump  313  uses the control signal generated at fill trigger switch  1309  to start motor  314  and cause pump  313  to start dispensing ink through needle  1302 . Motor  314  continues to run until timer  321  runs down to zero at which point the timer signals control input  317  to stop the motor and thus the flow of ink into the cartridge.  
         [0045]     At any point in the process the user may depress kill switch actuator  1312  to provide a control signal to control input  317  to stop the motor before receiving a control signal from the timer. The user may wish to do this for example when the needle proves to be incorrectly placed in the ink jet cartridge and ink does not flow into the cartridge as desired. In a final step, a vacuum may be applied to the print head of a newly refurbished ink jet cartridge to remove any air bubbles from the cartridge that may disrupt the flow of ink while the cartridge is in use. This vacuum may be applied through a suitable cradle connected to the housing  201  through a cradle attachment arrangement as described above.  
         [0046]     Although the illustrated form of the invention includes a timer for measuring the volume of ink supplied to fill the ink jet cartridge, other forms of the invention may use different arrangements for metering the volume of ink into a cartridge. For example, the volume of ink supplied to refill a cartridge may be preferably measured directly from a peristaltic pump, although any suitable positive displacement pumping device may be used according to the invention.  
         [0047]     The self-contained ink jet cartridge refurbishing system  200  described above has particular application in a retail ink jet cartridge refurbishing arrangement. Because system  200  utilizes cradle attachment arrangement  208  to quickly change ink jet cartridge cradles, the system can be specifically adapted to refurbish substantially any ink jet cartridge. The system can be employed in a retail arrangement in which a user brings their used cartridge to the retail refurbishing center, drops a cartridge off for refurbishment, and then later picks up the refurbished cartridge after the cartridge has been refurbished at the retail location. This is in contrast to prior ink jet cartridge refurbishing systems in which the cartridge had to be sent away to a central refurbishing facility. In another variation of the refurbishment arrangement, the user may trade in their used cartridge for a refurbished cartridge. An operator then uses the system  200  to refurbish the used cartridge and make it available to another customer dropping off a like cartridge.  
         [0048]     In addition, the compact size of the invention and its application for refurbishing a variety of ink jet cartridges makes it suitable for use in an office environment. As soon as office employees use all of the ink in the cartridges of their ink jet devices, they may simply refill the cartridges using the present invention without incurring the expense of buying a new ink jet cartridge.  
         [0049]     In any refurbishment application, office, retail, or production, certain additional equipment may be required to ensure the refurbished cartridge is in a usable state. For example, a testing unit such as Makro Micro Company, Croatia, Model CT8 or CT56 may be used to test each refurbished cartridge to ensure it is in proper working order prior to distribution to a customer or return to the user who dropped off the cartridge for refurbishment.  
         [0050]     The above described preferred embodiments are intended to illustrate the principles of the invention, but not to limit the scope of the invention. Various other embodiments and modifications to these preferred embodiments may be made by those skilled in the art without departing from the scope of the invention.