Too much has been told about this thing but never seemed to find something really specific. People may have given the right answer but didn't explain so in a way it felt more of the same. Even here I found what I think it was one way to do it but it wasn't explained.
I saw most people recommending CDXtract for this thing, but for some reason it never worked to me in that way (the images never loaded despite program showed it was loaded already). So after so long today I seemed to find a final solution for this and feel like explaining it here so hopefully it will be useful for somebody, now or in a future I hope. In any case there's always a somebody that don't know and might find this or that useful for the cause.
Before staring I'd like to clarify that this is not the only way, or at least I guess there must be other ways to make it, but I found this way pretty easy so this is it.
All you're going to need is Daemon Tools and Kontakt.

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This is how Kontakt looks in files area:




Yours will look different by obvious reasons, so whatever you have it will show up there, but similar.

Now, what we're going to do is to open Daemon Tools and mount the AKAI or Bin iso/file.
You'll notice the program recognizes only the cue file and when you mount it and try to access to the image you won't be able to do it, that's okay.
Once you mount the image you go straight to Kontakt, and file area and it will look like this:





You can notice something new showed up, that's the image, in my case some Kurzweil pack I got but in your case it will say whatever you got.
Now pay attention to the next capture:




In order to extract the image you will select the image, just one click needed and next click in the import button up there and the batch import windows will pop up.
Now you can do it as you want here, in my case I choose the same directory for instruments and samples, so in other words what you're doing there is choosing where the instruments and samples are going to be located so you're free to choose any location, in my case I do everything in the same location.
And finally once you're done you click in convert and you'll see it working in the conversion, ergo, the extraction, something like this:





May take a while depending on how big it is the image, you already know that.
And the final result:





I marked the number down there, that's obviously the number of selected files as it says there (in spanish). May look kinda messy but works totally fine.
For some reason the final size of this is smaller than the image per se. But still, as I just said it works fine. I remark this because it happened to me that I needed to convert some sf2 files before and there were much more samples but when I changed it to nki there were less samples, but when I loaded the nki all the notes were available to play so that's something I don't know but I can tell it worked just as this seemed to work as well and hopefully it will work for you as well.

I remember using MagicISO to open some bin files, that's another easy way too but for some reason I always had problems when it refers to AKAI images, always showing errors and stuff like that until I found this way to do it.

Cheers