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Hi all 
We disassembled the lawnmover motor and took out all the parts that we don't need for running on air.
Now we need to cnc a new cover for the piston so that it seals off those valves from the compression chamber. The cover will have two holes in it, one for ait input and the other for the air output. We are now working on a mechanical timing valve that will allow to comutate the air input and output at precise timing, but till then we want to run this baby using electronic valves:
I know that electronic valves can not switch fast enough to achieve high speeds, but it will do for testing purposes. So here is what we will try:
So when the piston is on its highest point, the electronic valve #1 will switch on and let the air in allowing the piston to move to its lowest point, then the electronic valve #1 will switch off and the valve #2 will switch on, allowing all the air to escape when the piston moves back up due to its inertia. This all will be commutated by two optotrigers and a cluminum commutator wheel. Wi will try 50:50 duty cycle. Here is the circuit I am intending to use:
Of course this setup will not be very efficient, because the air will move the piston only 50% of the time and inertia will do the rest. But it will teach us the basics. Also after these tests I could make a hole in the bottom part of the engine and arrange the air flow so that the first 50% of the period tha air pressure moves the piston down and in the rest time I could make the air flow in the bottom hole pushing the piston up from the bottom. That would be more efficient.
These electronic valves have a coil in them and that will make some BEMF trouble, so I probably will need to attach a neon bulb in the circuit or a secondary charging battery to protect the transistors
What do you think?
Thanks,
Jetijs
We disassembled the lawnmover motor and took out all the parts that we don't need for running on air.
Now we need to cnc a new cover for the piston so that it seals off those valves from the compression chamber. The cover will have two holes in it, one for ait input and the other for the air output. We are now working on a mechanical timing valve that will allow to comutate the air input and output at precise timing, but till then we want to run this baby using electronic valves:
I know that electronic valves can not switch fast enough to achieve high speeds, but it will do for testing purposes. So here is what we will try:
So when the piston is on its highest point, the electronic valve #1 will switch on and let the air in allowing the piston to move to its lowest point, then the electronic valve #1 will switch off and the valve #2 will switch on, allowing all the air to escape when the piston moves back up due to its inertia. This all will be commutated by two optotrigers and a cluminum commutator wheel. Wi will try 50:50 duty cycle. Here is the circuit I am intending to use:
Of course this setup will not be very efficient, because the air will move the piston only 50% of the time and inertia will do the rest. But it will teach us the basics. Also after these tests I could make a hole in the bottom part of the engine and arrange the air flow so that the first 50% of the period tha air pressure moves the piston down and in the rest time I could make the air flow in the bottom hole pushing the piston up from the bottom. That would be more efficient.
These electronic valves have a coil in them and that will make some BEMF trouble, so I probably will need to attach a neon bulb in the circuit or a secondary charging battery to protect the transistors
What do you think?
Thanks,
Jetijs
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