Switches to fill surge bin

[brentf]

Newby here. Hope I have placed this in the right forum
The objective is to fill a holding or surge bin with grain with an auger or conveyor driven with a motor and electric clutch. Once the bin is full the auger will not run because the top sensor turns it off in bin and stay that way until a bottom sensor in bin is exposed and reactivates the auger. The bin would likely 3ft by 3ft by 3ft. placed over a cleaning mill.
This would be a 12 volt system. The relay coil would be a typical 150 to 200 ma draw to be used to turn the electric clutch on and off. The electric clutch will draw about 5 amps. Basically looking for a 3 way switch to turn the relay off and on to run the auger electric clutch. The sensor in the bin could be of any type. Of course the principal of this system is when the bottom sensor is exposed the relay will turn on the auger and run till the top sensor is covered to make it stop. Now the auger will stay turned off even when the product drops below the top sensor. It will stay that way until the product is again lower than the bottom sensor. Once it reaches that point auger turns back on. The cycle keeps repeating. I was hoping to modify or use a cheap kit or simple circuit to do this.
open to suggestion and direction.
brentf

 

[BradtheRad]

So:

1) Sensor #1 sends momentary signal to switch on relay.
2) Relay turns on auger, runs independently. Ignores sensor #1 state change.

3) Sensor #2 sends momentary signal to deactivate relay.
4) Relay deactivates, auger turns off. Ignores sensor #2 state change.

A simple circuit called an SR flip-flop performs such a switching task. It can be assembled from 2 transistors or 2 logic gates.

 

[KlausST]

Hi,

Semms Brad did understand what you are asking for.

Me not. If you want me to help please provide a sketch and a clear question.

Klaus

 

[betwixt]

I read it as a request to stop and start the feed conveyor/screw so the bin fills up again when it reaches empty. There must be an outflow to the mill allowing it to empty as well.

If I'm right, there are several solutions to the problem but which is best will depend on how the level sensor can be attached to the bin. The ideal method would be to weigh the contents and use a simple weight operated switch but the mechanical aspects may not allow that. My second solution would be to use an optical sensor at the top and one at the bottom of the bin, if the light beam is interrupted by the grain you would know it was at least at that level. A simple flip-flop triggered by the sensors would say "I'm empty" or "I'm full" and operate the clutch accordingly.

It is also possible to do this with ultrasonics from a single sensor above the bin, detecting the level rather like a reversing sensor on a car detects the presence of an obstruction behind it but if the grain absorbs the sound waves or produces 'noisy' reflections it may not work reliably. There is also more complicated electronics involved although only a little more expensive than the other methods.

just ideas...

Brian.