Abstract:
A bulk ink feed system for an inkjet printer comprising a plurality of reservoirs coupled by a plurality of conduits through a plurality of inlet connectors on an ink cartridge carrier of an inkjet printer. The plurality of conduits contain an accumulator section adjacent the coupler. The accumulator section has a larger volume than the remainder of the conduit, which inhibits the reverse flow of ink from the accumulator section toward the reservoir section when the inkjet printer is not in use.

Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to ink feed systems for inkjet printers, more particularly, to a bulk ink feed system, and most particularly, to an after-market add-on bulk feed system for inkjet printers.  
       BACKGROUND OF THE INVENTION  
       [0002]     Modern inkjet printers are capable of high resolution printing of graphics. This is made possible by inkjet printers that have droplet sizes on the order of one to four picoliters. Very high resolution graphics and especially photographs, can be printed in multiple copies; however, photographs particularly require large quantities of ink. As a result, conventional cartridges utilized with inkjet printers are consumed relatively quickly. Because these cartridges are expensive, production use of inkjet printers to print repetitive graphics becomes costly.  
         [0003]     Bulk feed systems have thus been devised for use with inkjet printers. However, because of the proprietary electronics employed in the printers and because of difficulties in obtaining proper ink feed, these systems have marginal utility. For example, one problem with prior attempts to provide bulk feed systems is that once a graphic is printed and the printer is stopped, the ink tends to drain back to the reservoir. One means for solving this problem is to raise the reservoirs above the level of the ink cartridge; however, this tends to feed too much ink to the ink cartridge causing leakage and low quality output.  
       SUMMARY OF THE INVENTION  
       [0004]     The present invention provides a unique bulk feed system that utilizes the existing ink cartridge carriers in conventional inkjet printers. Conventional cartridges are modified to expose the ink feed fittings in the cartridge carrier. The modified ink cartridges are electronically reset to indicate the cartridge is full. In this context, applicant&#39;s ink feed system is designed for use with an inkjet printer, including a cartridge carrier, which carrier has an ink connection section and an electronic connection section. The ink connection section includes a plurality of inkjet couplers for receiving ink. The bulk feed system comprises a plurality of reservoirs for holding ink. A plurality of conduits are placed in fluid communication between the reservoirs and the corresponding ones of the couplers. Each conduit comprises a first portion having a first inside diameter. The first portion extends from a reservoir to adjacent an ink coupler. The remainder of the conduit comprises a relatively short accumulator section coupled between the first portion and the coupler. Preferably, the accumulator section comprises a larger diameter conduit than the first portion of the conduit. Finally, a modified cartridge is configured to expose the couplers and is adapted for connection to the electronic section of the carriage. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0005]     The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:  
         [0006]      FIG. 1  is an isometric view of a conventional inkjet printer having a cartridge carrier using the bulk ink feed system of the present invention;  
         [0007]      FIG. 2  is an exploded view of the cartridge carrier and portions of applicant&#39;s bulk ink feed system;  
         [0008]      FIG. 3  is a cross-sectional view of the cartridge carrier showing a modified cartridge and a conduit coupled to an ink coupler on the carrier;  
         [0009]      FIG. 4  is an isometric view of a modified cartridge in accordance with the present invention; and  
         [0010]      FIG. 5  is an isometric view of an assembled carrier with modified cartridges and at least one conduit in place. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0011]     Referring to  FIG. 1 , an inkjet printer  10  is shown in phantom outline. The lid  12  that covers the cartridge carrier  14  is shown in an open position. It is preferred, however, in the context of the present invention that the lid  12  be removed and that all of the area above the cartridge carrier  14  be open so that movement of the ink supply conduits  16   a - 16   g  can occur unimpeded as the carrier moves back and forth in the direction of arrow  18  over paper  20  being fed through the inkjet printer  10 . Referring to  FIGS. 1, 2 , and  3 , the inkjet cartridge carrier  14  is unmodified from the original equipment. A plurality of modified ink cartridges  30   a - 30   g  are inserted in the cartridge carrier  14 . A plurality of ink reservoirs  32   a - 32   g  are positioned on the support surface for the inkjet printer  10  adjacent to one side of the printer. A plurality of supply conduits  16   a - 16   g  connect the individual reservoirs  32   a - 32   g  to individual ink couplings  34   a - 34   g  normally located on the bottom of the cartridge carrier  14 . A plurality of conduits  16   a - 16   g  are shown in  FIG. 1  while only one  16   a  is shown in  FIG. 2  for clarity.  
         [0012]     Referring now to  FIGS. 2 and 3 , the cartridge carrier  14  is unmodified from its original equipment. It has in its right-hand section an electronic connection section  36  and on its left side an ink connection section  38 . The electronic connection section  36  has a plurality of receptacles  40   a - 40   g  for receiving the right-hand side of a conventional ink cartridge. Each of the receptacles  40   a - 40   g  in the electronic connection section  36  carries a plurality of contacts  42  on the inside thereof. In the embodiment shown, seven receptacles  40   a - 40   g  are shown. Conventionally, this cartridge carrier would normally carry seven conventional inkjet cartridges, the right-hand portions of which would fit in the electrical connection side and the left-hand portions would fit in the ink connection side. Each cartridge would have a right-hand side having contacts thereon that would make electrical contact with the contacts  42  on the carrier to provide information to the inkjet printer while the remainder of the conventional cartridge would contain an integral ink reservoir that would fit over the respective ink couplings  34   a - 34   g.    
         [0013]     In the modified version in accordance with applicant&#39;s invention, the conventional cartridges are modified by removing the integral ink reservoir and leaving only an electronic connection side as the modified cartridges  30   a - 30   g . These modified cartridges  30   a - 30   g  contain the original electronics which, among other things, communicate to the inkjet printer when the integral reservoir is empty or full. The modified cartridges  30   a - 30   g  may, when modified, have their internal setting indicating that the cartridge is empty. These cartridges can be reset with commercially available hardware, for example, a cartridge resetter for Epson ink cartridges is sold under the trade name JY 168-II, and are available from suppliers such as InkJetCartridges.Com, having an address at 99 Fifth Avenue, Suite 191, Ottawa, Ontario KIS 5P5, Canada.  
         [0014]     It is necessary that these modified cartridges  30   a - 30   g  be in place in the carriage  14  in accordance with applicant&#39;s invention so that the inkjet printer believes that a conventional cartridge is in place. Referring to  FIG. 4 , a selected cartridge  30   d  has electrical contacts  44  which correspond to the contacts  42  on the cartridge carrier  14 . The modified cartridges  30   a - 30   g  have also been provided with a handle  46  with which the modified cartridges can easily be moved. The modified cartridges  30   a - 30   g  fit in the receptacles  40   a - 40   g  and are secured thereto by an internal wall  50  that abuts against the left-hand side of each of the cartridges  30   a - 30   g . The wall  50  is held in place by arms  52  that extend between the wall  50  and the left-hand wall  14   a  of the cartridge carrier  14 . Thus, the modified cartridges  30   a - 30   g  are held in place so that the contacts thereon can be secured in electrical contact with contacts  42  in the cartridge carrier.  
         [0015]     Each of the conduits  16   a - 16   g  extending from the reservoirs  32   a - 32   g  to the couplings  34   a - 34   g  in the carrier  14  comprise an elongated tubular section  54  having a first diameter and a shortened tubular section  56  having a second internal diameter (the accumulator section). Each of the second tubular sections  56  is sized to fit over the ink couplings  34   a - 34   g  in an interference fit so that the tubular section  56  is in secure attachment to the coupling. The second tubular section  56 , because of its larger internal diameter, functions as an accumulator for ink immediately prior to the couplings  34   a - 34   g . In this manner, the ink can be supplied to the inkjet mechanism  60  forming an integral part of the cartridge carrier  14  in a continuous manner. In addition, when the inkjet mechanism  60  is not calling for ink, because of the increased volume of ink in the enlarged tubular section (accumulator)  56 , the ink will tend not to siphon back into the reservoirs  32   a - 32   g , even when the inkjet printer is unused for a long period of time.  
         [0016]     In a most preferred embodiment, the enlarged tubular sections  56  have an inside diameter of 1/8th of an inch and an outside diameter of ¼ of an inch. The tube running from the accumulator  56  to the reservoirs preferably has an inside diameter of a 1/16th of an inch with an outside diameter of 1/8th of an inch. The relative dimensions of the accumulator tube, however, can be varied from about 150% to 300% of the diameter of the smaller tube  54 . It is preferred, however, that it be about twice the diameter, that is, 200% of the diameter of the smaller tube. The accumulator can also be from one to six inches long, preferably from three to five inches long, and most preferably, about four inches long.  
         [0017]     In practice, the ink can be continuously supplied to the cartridge carrier  14  from the reservoirs  32   a - 32   g  through the conduits  16   a - 16   g . When it becomes necessary to replenish ink, the reservoirs  32   a - 32   g  need only be filled. The supply of ink in the tubes  16   a - 16   g  need not be disturbed at any time once initially primed.  
         [0018]     Thus, in accordance with applicant&#39;s invention, the inkjet printer  10  can be continuously supplied with ink from the reservoirs  32   a - 32   g . Thus, the inkjet printer can continuously function throughout its lifetime without the necessity of replacing ink cartridges.  
         [0019]     While the preferred embodiment of the invention has been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the invention.