The solenoids fire upward, pushing the pins into place, then the steel locking tines slide into place to keep them from slipping up or down until the line is refreshed. Meanwhile the solenoid stepper moves over to the next column.
One item missing from the diagram is a third perforated plate between the solenoid and the bottoms of the pins to keep the pins from dropping out. The locking tines would slide between the bottom and middle plates.
I'm not a CAD expert, having grown up with mechanical pencils and T squares, so my attempts at using a paint program as a CAD designer should be viewed with a bit of leniency
It might be as noisy as your typical impact line printer and should operate about as quickly.
I'm not saying it's the quietest or fastest Braille terminal to come down the pike, but compared to the prevailing designs which are effectively a solenoid for each pixel it's GOT to be a hell of a lot cheaper and at the very least should be considered for developing world applications
A 40 character by 1 line Braille display currently prices at around $4000 a pop! An 80 character by 1 line display prices in at $8 Freaking THOUSAND!!!!
I'd estimate the cost of manufacture of my design in relatively limited mass production runs would still average no more than a few hundred apiece. If it became a Braille standard device, costs could be cut to about a $100 or less.
Look at it this way. Current Braille readers, say an 80 char. display, contain about 480 micro solenoids and associated wiring and logic apiece.
My design cuts the active component list to 3 solenoids and a couple of stepper motors and associated control logic. Add in some perforated plates and 480 simple injection moulded plastic pins and you have a refreshable Braille Line Display 80 characters or as many characters long as you'd like.
No matter how you calculate it, that's GOTTA become a huge savings in the production costs and could effectively bring Braille computing to the sightless of the third world.
I read the other day that less than 10% of sightless adults today are even taught Braille at all and that of the small percentage who actually are employed 90% of them read and write Braille. The main reason for the lack of education is the lack of affordable options. Braille hardcopy and terminals are horribly expensive.
Also I read that India is looking desperately for an economical Braille terminal design to further improve the employability of the sightless.
People go blind at all ages from all causes ranging from disease to malnutrition to war and if this can ease the burden of the sightless around the world for less than the cost of a OLPC netbook, then I'm all for it.
Seriously I'm opening this idea to the public domain and make of it what you will, but it really would be huge benefit to the human race as a whole if we could expand the limited options available to the sightless today.
Gary
PS. The reason I'm getting involved in this is that I'm an amateur keyboard player and there are quite a few visually impaired keyboard players out there who would welcome an interface which would allow them to program the complicated beasts which modern synths have become.
I was toying with interfacing an 80 char by 1 line display with a Kurzweil PC3XXX series synth but I almost choked on my coffee when I saw the current pricing for Braille display terminals.
I had this idea years ago, but it never occurred to me to really start pushing it until I started taking a good hard look at what sightless people have to put up with in our modern world.
Anyway, here's hoping that other people online will pick it up and run with it. If there was ever a USEFUL gadget that people really need in our consumer spending driven world, THIS is the one that deserves all our brains and efforts.