Low cost air flow sensor

Step 1: Components

simple air flow sensor using scrap parts.

1, mouse center wheel
2, heat shrink tube 
3, used ball pen refill
4, lm358 comparator circuit
5, acrylic sheet
6, IR slot sensor

Step 2: Circuit diagram

Picture of circuit diagram

Step 3: Sensor assembling

Step 4: IR slot sensor MOC7811

MOC7811 is a slotted Opto isolator module,
with an IR transmitter & a photodiode mounted on it.
Performs Non-Contact Object Sensing. This is normally used as positional sensor switch (limit switch) or as Position Encoder sensors used to find position of the wheel.
It consists of IR LED and Photodiode mounted facing each other enclosed in plastic body.
Jestin_Cubetech (author) 2 months ago

goldenshuttle2 months ago

how can you identify which side is the sensor and which side is the transmitting diode on the slot sensor ? I have many of them of different sized, but no data sheet ? do u have any link ?

Jestin_Cubetech (author)  goldenshuttle2 months ago
janw5 months ago
I like the idea! You have my vote.
Jestin_Cubetech (author)  janw5 months ago
thank you
john pedersen6 months ago
What a great idea, good work. Voted.
Jestin_Cubetech (author)  john pedersen6 months ago
thank you

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