600-800hz 9vdc solenoid oscillator?

[repoman]

First off I apologize I've never taken any electronics courses what I do know I've pieced together. I need a control circuit for a 9-12vdc pull solenoid that varies the number of "ON" "cycles" per minute. Correct me if I'm wrong but this is called and oscillator yes? I run raw current through a resistor into a capacitor and then into the wiring for the solenoid itself and back to the power source and it should cycle on/off? do I need a transistor somewhere in here? The ultimate goal is a a device that reciprocates the solenoid around 600-800 times a minute on roughly a 9-12vdc 12000mah rechargeable power source providing 3-4 pounds of force over a distance of 1/4" linear pull travel for a split second. I dont need any exact rate of cycles but just ballpark, if there were a way to make this easy adjustable by replacing one part to increase/decrease rate that would make this project much easier. -IF- all this is correct so far can any tell me how to find the right resistor/capacitor values for this circuit?

thank you in advance

 

[Hero999]

600 to 800 cycles per minute is 10 to 13.33Hz, not 600 to 800Hz.

10Hz is pretty fast for a solenoid. I don't think the electronics will be the problem, it's the mechanics that'll be difficult.

 

[MOSFET KILLER]

Rig up a 555 timer to your frequency and use it to drive a power transistor and use the power transistor to drive the solenoid. Place a diode in parallel with the solenoid coil to short out the inductive spike when the transistor turns off.

 

[repoman]

600 to 800 cycles per minute is 10 to 13.33Hz, not 600 to 800Hz.

10Hz is pretty fast for a solenoid. I don't think the electronics will be the problem, it's the mechanics that'll be difficult.

you mean its going to cook itself to death or it simply will not be able to reciprocate that fast? I only need a 10% duty cycle on it. I looked for a dc motor with a gear/cam and couldn't find a solution to my issue

I have a small lathe and can make a cam to press fit on the shaft I only need linear travel of 3/16"-1/4" with a load of 4 pounds which not counting for friction puts me at a 1 inch pound need, do they make 12vdc motors that are that strong? and are capable of 600rpm?

 

[Hero999]

If it's low duty cycle, then you can use a lower voltage solenoid and over-voltage it which will give you more force and speed.

 

[repoman]

What about a large capacitor driven solenoid? I noticed that paintball guns have electronic triggers and are pretty much exactly what I'm looking for and have a capacitor driven solenoid that is designed for 10hz for is possible to up the capacitor and or voltage till I have enough juice to run an appropriate larger more powerful solenoid?

 

[Externet]

Hmmm... 3-4 pounds of force on 1/4" travel 12 times per second...
I would use a 12v motor geared down to ~700 rpm and attach an actuator 1/8" off its shaft center, as a locomotive wheel, or a reciprocating jigsaw.

Do this, just to test : Connect a 12VDC car battery to a 115VAC reciprocating jigsaw , check how far from your wishes it behaves and come back to fine tune the contraption.

 

[colin55]

I would buy a $35.00 jig saw.

 

[repoman]

I have some size constraints for the actual reciprocating mechanism but right now the 35$ 6vdc jigsaw might be the way to go

 

[Mike odom]

What about a large capacitor driven solenoid? I noticed that paintball guns have electronic triggers and are pretty much exactly what I'm looking for and have a capacitor driven solenoid that is designed for 10hz for is possible to up the capacitor and or voltage till I have enough juice to run an appropriate larger more powerful solenoid?

They probably put the capacitor in parallel with the solenoid to form a tank circuit. I've never heard of one oscillating at 10Hz before (usually used in rf tuning) but I guess it's possible... does any one remember the math for the resonant frequency of a tank (parallel LC) circuit?