Flex Circuit Cable Replacement?

[Mikehoch]

Hi everyone,

I'm working on a senior design project that will involve taking apart an Epson printer. For our design, we are going to need to extend the flex circuit cable (cable running from circuit board to printer cartridge). I guess my main question is how easy of a task is this to do? Is there a standard extension cable that I can purchase?...if so, where? I noticed that at the point at which the cable connects to the main circuit board, there seem to be some fairly standard-looking connectors. Perhaps I can buy a cable that can attach between these? I'm just not familiar enough with electrical engineering, so I don't know the names of these connectors or how to acquire them.

I haven't purchased the exact printer as of yet, so I won't be able to give specifics on a particular printer model. So far, I've only taken apart an old hp printer that my professor had laying around. I'm assuming, though, that most printers implement these flex circuit cables, and that most printers will connect to the circuit board in a similar manner. But I could be wrong... Any thoughts?

Mike

 

[mikling]

Buy two printers. get the extra flex and join properly. Simple enough?

Seriously go to a well stocked Industrial Electronics supplier and check their catalogues out. Unfortunately many of these type of items are not stocked and minimum quantities of thousands if not tens apply.

In which case, my sarcastic remark ends up being realistic.

 

[Mikehoch]

mikling,

Actually, the goal of this design project is to create a product that will be mass-produced, so ordering in large quantities may not be as unrealistic as it sounds. However, for our prototype, it would be nice if we could keep cost to a minimum. If I do buy from an Industrial Supplier, what the heck am I looking for? I'm not really sure what the cable/connector that I need is called. Is there a standard term for the cable that I need? Do I need to buy one that is specific to my printer model, or are they fairly generic? Thanks for your help.

 

[canonfodder]

Mikehoch,

You may have to do a bit of searching for the particular cable you need. It is a pretty good assumption that what you want might be called "flexible film cable" and you won't know just what type you will need until you open up the printer you are going to work with. Mouser Electronics at www.mouser.com carries some such products by Tyco Electronics. You might start by looking at Tyco's items at:
http://catalog.tycoelectronics.com/TE/bin/TE.Menu?M=MENU&ID=17787&LG=1

The basic flexible film comes with different numbers of conductors. For your first start, you could cut a cable with excess conductors down by careful Exacto knife work.

The basic flexible film comes with different spacing of the conductors. Popular spacings are 0.1 inch and 0.05 inch.
You might find that the printer has metric spacing of the conductors. Measure carefully.

IF you can find the item you need at an electronic distributer like Mouser or Digikey or etc. you will probably be able to buy small quantities. Some shorter lengths are sold as "flexible jumpers" or "flexible jumper cables".

Connectors may be a large hurdle. Tyco has some, but lots of things like printers are built with connectors made just for the product. I hope you have good luck on that part of your search.

 

[Grandad35]

This might not be a problem in this case, but is it possible that the impedance of the flex cable is tuned to the impedance of the printer's drivers? The higher the frequency of the signals on the cable, the more critical the design of the cable becomes. Changes to the cables can create unexpected and unexplained problems if they are operating near their design limits.

 

[Trigger 37]

Mikehoch,... mikling may have been kidding but his idea would work. Buy your new printer and then find one that is broken and being sold for parts. You can use those cables to extend it outside. Make up a very small pc board and purchase and mount to identiacl flex cable connectors that are used on the logic board. The pc board is just used to connect the to flex connectors one to one. You may have to take the printhead carriage ASM apart to get the cables out. On a broken printer, I would bet 99.99% of the time the flex cables would be ok. Other cables can be extended the same way. I'm much more familiar with the Canon cables, connectors, printheads, carriage asm, and I can see how that could be done. I'm not that confident about the Epson. By the way, why did you pick Epson. The Canon printers are much less problematic.