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Manual air compressor Answered

I had this idea just drop on me a few minutes ago and I was wondering if anyone could give me some feedback on if something like this would be feasible or not.
Also if anyone thinks it's a good idea just go ahead and build it because I dont have the tools or space for something like this in any case.

The idea is to have some sort of tank with a large internal volume, cut it of at the top and arrange a sort of secured piston with a heavy weight on top, attach it all to a frame so that the piston stays level and secure.
The piston with the weight on can then be connected to a multi-stage pulley system to allow one to lift the  heavy weigth, sure it would take a long time but for a manual air compressor it should be feasible
Then at the bottom of the tank one would have a high pressure release valve with some sort of standard connector for transfering the compressed air to a sort of pressure tank for use.

I never saw anything like this before, although I'm sure someone must have done it at one point or another.
So what do you all think?
Any input?


Instead of using a huge heavy weight to push down on the air compression chamber with one big piston, how about using a powerful spring, hooked up to a ratcheted lever. This would be compressed to a certain maximum compression pressure, then use this spring compression to drive an air compressor. Otherwise just use a big strong air pressure tank as the spring; use the ratchet to allow air into the tank but not out. Now lever action is used to compress the air in the tank directly. This takes the place of the huge weight having to be lifted. Either way, the ratchet system divides the input work energy into small increments and the lever system makes the small increments less difficult to achieve. A small hand operated hydraulic air pressure pump, starting with a base pressure of 90 psi which can also be achieved by hand pumping, can then be used to pump air pressure up to 10,000 psi in a large air pressure tank made for this high pressure, such as a carbon fiber composite tank which is burst tested to 20,000 psi or more. So then you will be storing the energy created by your muscles via the lever/ratchet/pump system, directly into the "spring" of the air mass being compressed into the air pressure tank. The tank could then provide power to a house or car or whatever, by powering rotary Wankel air motors which operate quietly. See Angelo Di Pietro, EngineAir Australia. Di Pietro worked on air motors with Mercedes-Benz in Europe before starting his own company. Top award-winning GM Cadillac Aera concept car can travel 1000 miles on one fill-up of the air pressure tank filled to 10,000 psi. This should get anyone's attention. Carbon fiber construction keeps curb weight of this large car down to 1000 pounds. If you remove the wheels, suspension, etc., it is even lighter and can be the basis for a VTOL aircraft (vertical takeoff and landing). It may sound crazy but I think this can be powered using hand-operated ratcheted air pumping system as described. Sounds like a lot of work, but one can lift a car or large truck with a properly sized, simple hydraulic bottle jack and hand lever. Think of all the human energy available in a typical workout gym. Perhaps a half-hour workout would be enough energy to get to town and back by VTOL aircraft, and perhaps could carry groceries and other needed items.

Is there any evidence that the Cadillac Aera can drive any practical distance in the real world? Concept cars are often just wishful thinking, like the atomic powered concept cars of the '50s. Some recent concept cars were imagined to be grown from seeds.

As for the original idea... pistons leak. Bellows would be somewhat more practical. Or, just hook up a compressor pump to a bicycle. Certain auto air conditioning compressors can be used as air compressors. Google on board air and York compressor.

The original lifting system of Tower Bridge in London uses a system very similar to this with enormous concrete weights lifted by steam engines. 

(Pssst - It's not announced officially yet, but Tower Bridge is for sale and I'm acting as agent.  Let me know if you're interested. )

Interesting.. I wonder how big a steam engine you'd need for something like that provided you use an efficient pulley system..

I'll tell you what, I'll trade you the bridge for an interview with the head of the London police department, how does that sound? :)

The answer is Very Big - I'll post some of the photos I took on a trip around it last year.

(err...I'm afraid the bridge has just been taken off the market - Must dash #;¬)

.  Do some math first and see if it's practical.
.  Let's say you have a piston that is 12" in diameter, That gives you a surface area of about 113 square inches (pi * r2). If you have 10 psi in the cylinder, that's 1130 pounds of weights.
.  If the cylinder above is 3 feet long, you can store ~340 cubic feet of air at STP.
.  If you need a precise, low-volume pressure source, you have a great idea. Not so good for a high-volume shop compressor.

But wouldn't it be possible to fill a large volume container in several goes if one had a regulated release/transfer valve system at the bottom of the tank?

at some point, the pressure inside will equal the pressure of the "incoming" air, and will not allow more in without an increase in the "input".


7 years ago

I was imagining a setup where a pre-determined set of weights could be used to achieve different pressure levels or if possible just using a sort of valve that could regulate the PSI output like I mentioned earlier.
I mean that should be possible, right?
Then simply making the tank rather big so that the volume wont be a problem..?


7 years ago

But wouldn't it be best just to have a rather high pressure in the tank and then simply regulate the transfer to whatever tank one was going to use by some means?
That way one would be able to use it for a lot of different tasks and psi levels.

It depends on what you want to use the compressed air for. Experimental deep sea diving air supply, run air tools like a nailer, impact driver, or paint sprayer, aquarium air, bottle rocket, fill up a car or bike tire, etc? You need to match the flow or delivery rate of compressed air and pressure to your application. Based on that you can figure out how heavy a weight and volume needed for your piston chamber. It's simple enough to build such a contraption but probably not practical if you need a lot of air. How about a giant bicycle pump but attach that to an eccentric drive wheel to crank by hand or foot?