Pneumatic Flip Flop Circuit

This 3/2-way pneumatic valve acts as a logical NOT gate. It takes the circuit's output as its input, it then inverts it and connects it to the circuits input. It allows the circuit to toggle its state with every input pulse.

This 3/2-way pneumatic valve acts as a logical AND gate. It takes as input the control signal and when the control signal is active, it connects the output of the NOT gate from Part 1 to the input of the 5/2 valve from Part 3. When the control signal is inactive, all ports are blocked.

This 5/2-way pneumatic valve is the main valve of the circuit. Its job is to separate the circuit's input from its output. The valve's input is dependent on the current state of the flip flop. If the flip flop is currently in the high pressure state (logical 1), the valve blocks all ports keeping the pressure trapped in the output compartment (anything to the right of this valve). If the flip flop is currently on the low pressure state (logical 0), then the valve is in its default position, connecting the circuit's input (anything to the left of this valve) with the output compartment. As a result, when the next control signal comes and the leftmost valve activates, pressure will flow from the output of the top-left valve to fill the output compartment.

This valve serves as pressure level reinforcement. Its input is dependent on the current state of the flip flop. If the current pressure in the output compartment is above a certain threshold pressure (determined by the actuation pressure of the valve you choose) then the valve will connect the circuit's output with the pressurized air supply, ensuring that the pressure in the output compartment will always be at 100% of the maximum available pressure. If the current pressure in the output compartment is below the threshold pressure, then the valve will connect the circuit's output with the atmosphere, ensuring that the output pressure is exactly 0. The idea here is to keep the output as close to binary as possible and avoid (for example) pressure drops over time due to leaks when in the logical 1 state, or parasitic pressure trapped in the output in the logical 0 state.

Lastly, the state transition valve has 2 jobs. When the control signal is inactive, it connects the pressure-level-reinforcement valve from Part 4 to the circuit's output so that it can do its job. Now, when the control signal is active, it blocks the pressure-level-reinforcement valve otherwise it would be impossible to change the flip flop's state, and it connects the circuit's output with the atmosphere via a flow control valve. That is done so that when we switch from the logical 1 state to the logical 0 state, the pressurized air that was intentionally trapped in the output compartment can slowly escape, thus releasing the main valve from Part 3, thus freeing the remaining air and allowing for the state to switch. It is critical for the flow control valve to exist, otherwise, trying to change from a logical 0 state to a logical 1 state would result in air freely traveling from Part 1, via Part 2, via Part 3, via here to the atmosphere, blocking the system.