Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

Astable multivibrator to switch electromagnets

Status
Not open for further replies.

ElectroNewbie

Newbie level 3
Newbie level 3
Joined
Dec 15, 2014
Messages
3
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
28
Hi, this is my first post so please let me know if I'm in the wrong place

I'm trying to find the simplest circuit diagram possible and hopefully with no soldering, (I'm very new to this) for what I think is termed an Astable multivibrator

I want to create a seesaw effect with a metal bar on a central swivel point with an electromagnet underneath each arm of the seesaw. The circuit should switch on the current on one of the electromagnets and off on the other and then swap over. This would make the metal bar move like a seesaw.

I would like to be able to adjust the speed that the circuit switches back and forth from about 1 cycle every three seconds to about 5 cycles a second. I think this would be with a variable resister? The circuit for the electromagnets would be separate to this circuit which would only do the switching. Would this be difficult to accomplish?

Thank you
 

You could use two time-delay relays. No soldering, but lots of money. Now might be a good time to learn to solder! I would look at using a 555 timer and a couple of transistors. They are cheap and plentiful. But if you REALLY don't want to solder, you could use a breadboard.
 

Thank you for the reply - despite it being particularly unhelpful, at least someone took the time to read the query
 

Can you give some scope? Purpose? This has many effects on choice on iron mass and coil power you had in mind and method of balancing the accelerating forces on both sides so it is symmetrical also what power source you had in mind.

The mass x EM force is proportional to current * time interval and coupling of coil to iron gap distance which results in a natural frequency of oscillation when toggled. It can also be pulsed in each direction then coasting until next opposite pulse. Or it can be smooth sinusoidal like rhythm but loose travel displacement when mass or friction is applied.

It is useful to understand that Current in each polarity or each coil imparts a force on the iron and does not determine the position which is the 2nd time integral of acceleration.
 

Thank you so much for your reply. I envisaged a low powered circuit that controlled two relays switching them alternately on and off and that the relays would then control the electromagnets I wasn't so concerned about the electromagnet side of things at this stage, just the ability to switch the relays. I could sort of understand that an astable multivibrator would be what I was after, but I need to be able to adjust the switching times between
about 1 cycle every three seconds to about 5 cycles a second and working the timing out is, I'm afraid, a long way past my capabilities.

I saw an astable multivibrator circuit that switched LED's alternatively on and off but could not see how the solve the variable speed side of things.

Sorry if I wasn't clear in my first post, but it is just the problem of the variable switching circuit that I am trying to address.

Many thanks again for your reply
 

Status
Not open for further replies.

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top