automatic feeder help!

[maxkd]

Hi guys forgive as i am a novice to electronics.Basically i am looking to make an automatic feeder/timer that could drop or feed a tennis ball every 5 secs plus.If anyone has anyideas i would be very greatfull obviously the simpler the better for a novice like me,i tried to find a way with a mechanical timer to keep it ultra simple but to no avail.Im guess ill have to use a 555 timer or something not that i really know how to use one!

 

[Sceadwian]

Why bother with complicated electronics? It can be done with very simple gearing. Use a worm drive and just gear it so it pulls a ball out of a bin at whatever rate you want, and the launcher is easy enough to make with a simple rubber tire and flywheel. Could easily all be run off one motor.

 

[maxkd]

Thanks sceadwian,yes im going to use a fly wheel and tyre ,hadnt thought of the worm drive idea tho so thanks for that, you know a good place to find one big enough?out of interest as you seem fairly genned up what motor,size wheel and power source would u use if you were to build one?Most machines use 2 wheels spinning in opposite directions but i am hoping i can just use one as the whole point is to keep it simple,i was going to use a cordless circular saw and replace the blade with a tyre,im just hoping it gives me enough rpm to kick the ball out a fair distance.

 

[evandude]

I've never built such a thing, but I would think if you just used one powered wheel and another fixed (or free-spinning) wheel, you'd have to worry about putting a serious spin on the ball. maybe with an idler wheel that spun on a ball bearing it wouldn't be a problem... But two powered wheels running at the same speed seems like a good way to guarantee that no significant spin is imparted.

 

[Sceadwian]

Something large enough to do tennis balls should be easy to find at a junk yard that has farming equipment, any generic screw conveyor type auger will do. Spin might be nice to add later, but evan's right, everything I've ever seen that does this uses two wheels to keep the spin relatively neutral, you can launch things at incredibly velocities (way more than a human ever good)

Something like
https://en.wikipedia.org/wiki/Screw_conveyor. Very very easy to make.