March 28, 2015 at 1:26 pm #2209dragonatorKeymaster
In the still ongoing pursuit for a new printhead for a printer, there is now another contender. With the HP642A stalling a bit due to complexity, something else is needed. This is the HP45 series printhead. Now starting with the drawbacks, it is not ciss, and it is very hard to convert to Ciss, due to an internal vacuum caused by a spring. Then WHY?!? Here’s why, but first some specs:
44 ml ink capacity, hollow tank, no sponge.
12V operation (to my knowledge)
Minimum trigger frequency: 12kHz
This information is known, and there are some curious things about this cartridge. While it is very old, they are still available. It is one of the last generations of directly driven nozzles, it has around 50 contacts on the back of it driving the nozzles with a grid of triple multiplexed Fets. The voltage supply is always high, the right port is opened (sunk to ground) for about 4us, and the gate of the fet is then triggered for around 0,5us. This is based on some measurements of someone I know of, and based on the patent, that is ridiculously descriptive. It has pinouts, schematics, triggering diagrams, rough power consumption (25A!!! peak) and is more datasheet than patent.
I now have 2 of them, I will try to hack them with an external controller, The person who gave me the timing and voltages is also working on making these hacked, and I encourage more people to do it. I am moving in the near future, so my time will be a bit more limited for a while. But for now, I feel that these printheads might be the right step forward for 3DP printing.March 29, 2015 at 10:47 am #2210wonkoParticipant
Pretty much everything you need is here: http://spritesmods.com/?art=inker&page=3
Those cartridges are still well in use in the industrial field. They are incredibly robust. I have seen them on automated wood cutting plants to put serial numbers on freshly cut wood. They are also used in professional large-format plotters for architects. There is an official CIS available, but I forgot where I found it.
I have known about these for a while, but they are quite large and require hundreds of connectors for the five colors that I want for full-color 3D printing.
- You must be logged in to reply to this topic.