![hp officejet pro 8500 a910 clean print head hp officejet pro 8500 a910 clean print head](https://i.ytimg.com/vi/eBhFMn9NEHo/maxresdefault.jpg)
Also, the circuit board wasn't badly contaminated when I took everything apart. The bottom of that opening opens into the waste tank and there is a small plastic cover over that protects the gear shaft. My assumption is that it baseslines the response from this device. The retractable cover now open (red) must be significant because there is a pretty intricate mechanism that pulls the cover shut covering the opening and then it snaps open when a spring under tension releases. Not sure if the printer never got that far or whether this is by design. I have not seen any ink inside the rectangular opening after my cleaning. Inside the metal antenna you can make out the circuit board with one SOIC-8 OpAmp and some resistors. You can also see the retractable cover (blue) over the rectangular antenna (red). The first is when the two suction cups (green) are under the print heads. Let me add some images for clarification of above. Else this printer would have had an accidental fall to its death by now. I am frustrated - too bad I am not living in a 10 story high-rise. I have not (yet) found a way to remove and clean the heads without the printer noticing. If I decide to re-do the ordeal I might end up with one or two colors looking better and another being completely gone. In other words once it makes it through one of these super extensive cleaning routines to the point where it actually prints a test pattern one or more colors are impaired to various degrees. because when I do get the printer to print it remains in whatever state it then is. As a result the ink delivery system can not keep up with ink consumption during the sucking on the heads? The refill pigment ink (NanoDigital pigment) I am using is so bad it clogs some of the nozzles right away during the test shots in the cleaning cycle.Ģ. When I take the heads out and put them on moist paper the is no blotting pattern. In the process it all craps up and if I get lucky to where decides to finally print most colors are missing. But when I put them back into the printer it literally keeps sucking on the yellow for 10 minutes or more until the tank is empty. In my case I am able to make my printheads happy when soaking them in cleaning solution to the point where they show some acceptable blot pattern for all 4 colors. If not how does the mystery devise measure? And what's with the moving cover? I was not able to see whether they also spray through this mystery device. Has anyone any information on what this device does and how it works exactly? Is it some sort of flow meter? Does it measure whether the spray passing through it is dense enough? The printheads seem to spray to a little blast plate angled at 45 degrees in the waste tank. For lack of better description the metal cover looks like a WiFi antenna. And then this is connected to the main PCB. The opening has plastic sliding cover that at times covers the opening (when the cleaning cart moves to the back) and then snapps back again pulled by a spring. It has a metal antenna (my guess) with a rectangular opening and a second metal shield. However, here is a small PCB in a plastic cover on the left side of the cleaning unit. None of the above has any sorts of smarts or sensors to "know" if the cleaning did anything. They just wipe off dried ink from the nozzle area.Ĥ. There are four (two for each) rubber wipers on that same movable cart. Ink first gets sucked into a little canister and then purged into the bigger waste tank with the sponge.ģ. At the same time Some of the lines get pinched. When the cart gets moved under the print heads they suck on the printheads and force ink through them. There is a small peristaltic pump connected to what looks like two rectangular rubber funnels on a movable cart. What a mess but I cleaned it all up and washed the sponge.Ģ. It was saturated and ink was sloshing around in the bottom. The waste tank has this enormous sponge inside. So in an act of desperation I took the whole thing apart to try and understand how it decides on success for the cleaning routine.
![hp officejet pro 8500 a910 clean print head hp officejet pro 8500 a910 clean print head](https://m.media-amazon.com/images/I/71WsQZGOAcL._AC_SX355_.jpg)
My printer won't stop trying to clean its print heads.