Autopsy of a Maxify Printhead

As I mentioned in @palombian’s Maxify thread, the printhead of my MB5150 perished suddenly.
This thread intends to be a rough autopsy of a QY6-0087.
I’m not a skilled surgeon by any means, so I leave it to more experienced hands to continue exploring.

-Overall view from above with the cyan and magenta slots removed and the bottom plate open.


-The printhead has an upper half which is simply a frame holding the cartridges in place. It can be taken apart removing two screws.



-Lots of screws inside.



-The bottom doesn’t features the usual ceramic plate of other Canons. It’s hard smooth black plastic. I don’t know if they changed the material for economical reasons or if that plastic is better suited than ceramic for technical reasons.


-The rubber gasket sealing the bottom plate and the ink chambers. At left the larger hole for the black channel. At right 6 round holes, two for each color. The bottom hole has no connection to ink channels. I guess it serves as a guide for aligning accurately the gasket, because it fits in a plastic prong on the upper side.



To be continued .....

-The bottom plate from inside




-That part shaped like a boat is the one with the contacts that connects the chip to the gold platted surfaces at the back of the printhead. It has a bit of vertical rotation, probably to allow for a certain flexibility when inserting the cartridge. It’s inserted in a slit on the frame behind, I couldn’t remove it without breaking open that slit.




-I removed the cyan and magenta slots and you see that below the 5 five smaller contacts of the chips there’re two extra larger contacts below, Those are connected to the ink flow detector.


- When the upper part of each ink channel is removed we can see what’s inside. At the bottom, on the part going to the nozzle plate there’s an oddly shaped part, like a certain piece of woman underwear.., let’s call it pentagon . It’s made from the same hard porous material of the resting pads.


To be continued..

-Two views of the upper part of the liquid chamber.

From below



Sideview


As you can see, inside the upper part of each ink chamber there’re two metal pins connected internally to the ‘V’ shaped springs going back to the wide contacts at the back of the printhead.

Those pins are inside the ink chamber, but don’t reach the very bottom of it. Normally this chamber is filled with ink, If, for any reason, there’s no more ink, the electrical resistance changes suddenly and so the printer knows that the ink chamber is almost empty.


-For a better view, the former photo is rotated 90º but in fact, when installed in the printer, it looks like this last photo.

Excellent job, Artur5! The drawing really tied it all together.