4 pumps to fully inflate

[Lost Sheep]

Four pumps to inflate? It would have to have a big ball, not a practical item. I think what they have now is actually very nice if the pump is working the way it should, but mechanical things do fail and the pumps are mechanical. But I do believe they could make a pump that would never fail, it is a very easy mechanical item. All it is a check valve. Opens when you squeeze the ball because it is pushing saline from the reservoir to the cylinders, and it closes when the ball recharges with more saline. I read an article many months ago that the reason why some fail is because at the factory they did not add enough lubricant where the check valve is, and that it gets stuck and quits working. Not sure whether to believe that or not. I do no that I had trouble from the start on my first revision with the MS valve sticking. Had it replaced and this one works perfect.

Simple check valve is good and just as you described. But that is only one-third of the story. What you describe is good for inflation. Another third of the story is deflation. The last third is how to switch between the two functions.

And THEN, they have to make it simple to operate, since the user cannot see what is going on.

I discussed with my surgeon a mechanism whereby one could pump the implant up with positive pumping action (as is done now) and then DEflate the implant (inflating the reservoir) with positive pumping action. He was interested and asked for me to let him know when I figured out how to do it. To get a system with either one pump bulb with a switchable valve or two pump bulbs (I figured the upper one for inflation and the lower one for deflation - easy to tell apart) that would be small enough has proved an engineering challenge.