i have this simple pump that i’m trying to hack and replace it’s push button with an IR Proximity Sensor.
first let me explain how it works right now:
- you press a button and it starts the pumping and last for 90 sec and shuts off (ic 555) is used for this purpose
- while running you press the same button and it stops.
runs on 5v.
so what i’m trying to do is the following:
- install an IR Proximity Sensor to start the pump while in proximity and stop the pump when my hand is away from the sensor.
- limit the pump to 0.5sec min instead of a fixed 90 sec (for this i need to locate the fixed R and replace it with a potentiometer to allow the tweaking of time and replace the current cap with the right one to achieve a minimum of 0.5sec operation)
where am i right now:
- i have the IR Proximity Sensor powered by the same board VCC and GND.
- i have attached the signal of the IR Sensor to one of the legs of the button.
- when the sensor is activated the signal goes high and the pump works.
the problem is the pump continues to work even if i remove my hand away from the sensor and only shuts off if i bring my hand in front of the sensor meaning the signal goes high again. not the desired outcome i’m looking for
can you guys please help me figure this out… remember i do not have any schematics and i want to achieve this as cheap as possible so no Micro-controllers involved here.
Thank you guys
as for the timer:
i suspect that i will need to replace C3 and C4 or at least remove one to reduce the time, no???
also should the potentiometer would go in place of R1 ??
Thank you guys and Cheers,