How can I make a sensor that will turn off my dust collector when the bin is full?

I am installing a cyclone dust collector in my workshop, and I want to make a sensor that will determine when my dust bin is full so that the chips and dust won't overflow into the filters.  I'm thinking garage door sensors could be blocked by sawdust rising into the transparent flex hose between the cyclone and bin, but I'm not sure how they work.  I would use them to turn on a warning light and turn off the dust collector.  Any ideas?  I'm good with tinkering and basic electricity, but am stuck trying to figure this out.

sort by: active | newest | oldest

Tricky. Light path sensing is problematic around all that dust.

How about weighing the bin ? There can't be a huge variation in the weight of a full one.

Commercially they would do just that weigh the bin.

or Put a light sensor in a position where it will be covered by the contents as they approach the top. a simple LDR will give a light dark switch signal.

I guess this doesn't need to be too accurate.

woodwringer (author)  rickharris2 years ago

Pardon my ignorance, but I don't know what an LDR is.

Light dependent resistor. I'd forget light based approaches, if you don't want false triggers and cleaning work.

i forgot to say the sensor will need cleaning every time you empty the bin.

perhaps if the bin fills from the bottom up a modification of a toilet ball valve would do it. A flat plate on an arm sitting on the top of the contents and a micro switch.

Weight sensor, float and optic sensors are useless.

Even when the tank is empty optic sensors will be blocked by flying particles, and floats only work with liquids.

That leaves you with weight sensors.

iceng2 years ago

A tiny low power rotating fan DC motor will stall when dust reaches it. There is a small current increase when the fan is stalled that a comparitor IC can easily detect and will provide the logic signal to stop your cyclone motor...

Get a broken, bagless vacuum from the scrap.
Inside on a little circuit board you'll find a little plastic thingy with a flexible hose going somewhere - this thingy is a pressure sensor.
Depending on the model the electronics might have no function to shut the vacuum off and the "thingy" only causes a lot of noise, you might have to check 2 or 3 to get the right one that works for you.