Post by jjackson123 on Jan 30, 2013 19:28:29 GMT -8
Here's a video I came across that shows building an air car is so simple a child could do it! And did. m.youtube.com/#/watch?autohide=1&autoplay=1&v=sb5R8fuc-Vk&version=3 His design is reminiscent of Terry Miller's Air Car One but without a second stage and only using one cylinder and a spool valve. I have no doubt that Terry was his inspiration for this, but you gotta love it!
Post by Uncle Buddy on Jan 31, 2013 17:13:49 GMT -8
Terry helped a high school physics class build an air car like his, and when they graduated the car was put in a museum. The car was in an air car race against Terry's and the students won.
Terry's great contributions include showing us we can build an air car with mostly off-the-shelf parts bolted to a frame. Then he showed us that people love all air cars, because his workbench-on-wheels was shown from coast-to-coast and appeared on the front page of many small town newspapers. He showed his air car in Times Square, New York City. The cost of building the car was $1500. Later in the 1990s when he had a new design for the engine so he could retrofit conventional car bodies, he was taken seriously. All the major components were GIVEN to him by big corporations in exchange for a DECAL on the side of his air car. This is because he was the sort of person who was not afraid to ask for what he needed. Terry was a one-of-a-kind inventor. Most of us want to get there alone, and we do get "there" alone: to our grave!
Given to him for his second run at air car development: spool valves, actuating cylinders, huge air tanks for the air station, big engine and four-stage compressor for the air station, I don't know what else.
According to the engineer who took over for Terry when he finally quit the project due to bad health, the 4 stage engine wasn't that great, he tested it on a dynamometer and came to the conclusion that some of the stages were a drag on others. I have done the math and the engine put out no more than 4 or 5 horsepower; the engineer said less than 2. This is part of our education. It shows us how little horsepower is needed to make a car roll down the road, especially when the engine has massive torque, as does a slow-moving piston air engine. Terry's workbench-on-wheels was also able to pull a big pickup truck down the road.
Terry didn't believe in putting compressors on air cars, but his predecessor Obid Smith did. Obid's air car toured 11 states, travelling 9000 miles. It climbed Pike's Peak like it was flat. Part of his secret was keeping an even temperature, which reminds me of some things Tommy has been trying to teach us. Obid also shared the perspective that a car is not running under power more than 40 or 50% of the time, on an average. Under these circumstances it would be silly not to have a compressor on board.
Obid's supporter was the famous actress Gloria Swanson, who had an inventors' helper agency. As a result, in 1940 when the census taker asked Obid what he did for a living, he was able to respond, "I build air cars!"
I have located Obid's descendants but oddly enough, they will not respond to my messages on facebook. If I was Terry Miller, I'd get on the phone and call them, and then they'd talk to me. What the world needs right now is the next Terry Miller.
Post by airpowerman77 on Nov 28, 2015 11:31:02 GMT -8
I'm ready to build the most advanced compressed air car. But I need some questions answered. 1 who currently has the most efficient air engine design, 2. who has the most efficient thriple expansion chamber design, 3. who has the best air over hydralics for moving the car down the road, ( the new French car has air over hyd.) I would like to put the best combination together this year. Terry-Lee
Post by Uncle Buddy on Nov 28, 2015 16:45:03 GMT -8
The most efficient air engine was patented by Charles B Hodges in 1907. His patents are reproduced in my free book The Air Engine that Got Air Engines Covered Up. This was a two-stage engine and the European version took it further by adding a third stage. A researcher in Europe told me that they were getting ready to go back to 2 stage when the war hit and put a stop to the whole project. The reason would be that, despite 3 stage being more efficient at ideal conditions such as at certain speeds, the rest of the time the third stage would be a drag on the first two.
For a stationary application, the most efficient air engine would be important because there's room for it, so why not. For a car, or anything really, I'd suggest the best way of compressing air is most important so that you're not already in debt when you get ready to consume your saved up air. Because air is heated by the sun and is readily available everywhere, it is in a unique condition to be used for free or nearly so, if you can find a way to get it into the tank for free or nearly so. The pressure already in a pre-filled tank represents a pool of energy much greater than what's needed at any given moment to get the car rolling or keep it rolling at any speed. There is therefore plenty of extra power to run some hypothetical process of air injection into the tank so that tank pressure never has to go below a certain threshold.
Because of the amazing torque and small size of the LEAST efficient air engine, I recommend that you use the least efficient air engine and exhaust it into the suction port of an injector (venturi pump or jet pump or ejector, etc.) The injector does not feed air to the engine but to the tank. Tank air is heated on the way to the engine by electric resistance heaters which is 100% efficient. The injector drive air comes from a number of compressor pistons which set up a wave in the pipe such that the injector drive pulses at up to 225 psi while the average pressure in the compressor discharge pipeline is much less.
The least efficient air engine is so small and so powerful that this is really the way to go. It just needs a low pressure zone to exhaust into. The creation of high pressure pulses is simple acoustic power available in the discharge line of every compressor if we know how to tap into it. Acoustic power separates air into high and low pressure zones that we can take advantage of. The injector works extremely well with MOVING air being induced into its suction port by PULSED drive air.
Otherwise you can store 4000 psi in tanks on your car instead of having a place for people to sit, and stop to fill up the tanks every 30 miles or so.
The least efficient air engine is so small and so powerful that this is really the way to go. It just needs a low pressure zone to exhaust into.
Forgot to say why: the least efficient air engine is non-expansive, it barely loses any pressure when used. Normally it exhausts to atmosphere so all that pressure is lost. But it's a powerhouse with full torque through the whole stroke unlike the efficient expansive air engine with dropping torque thru stroke. Which then needs a big flywheel to even out the impulses and get it to the end of its stroke.
If the non-expansive air motor is instead exhausted into a temporary suction zone in an injector which then puts it back into the tank, we have a situation on our hands! The least efficient air engine then becomes the most efficient as well as the most powerful and smallest air engine.
People love air cars and I would avoid too much experimental engine stuff. Put your energy into getting large amounts of fresh air into the tank for free or nearly free, and re-perfect the air engine, which was perfected once already in the 19th century, after you've re-established Detroit in your home town.