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Appropriate Switch

  • 14-08-2014 4:27pm
    Registered Users Posts: 18

    Okay so I am a complete noob when it comes to circuits and anything electrical but for a college project I need to incorporate electronics.
    The project is based off Dynamic Mechanisms, basically using gears, pulleys, cams etc. to make a project become a playable scene. Therefore my circuit needs to be perfect for my project to work. Once I start operating the scene I cannot have any room for error.
    But here is my issue...
    I have a basic light bulb circuit which is operated by a push button switch. When this switch is turned on the light source then activates a light activated sound module which plays a song.
    However this switch is activated by an involute cam (snail like gear) , when this gear is at its highest altitude it will operate the switch. however by the time the gear comes back around to turn off the switch the song is only a third of the way through.
    I was wondering is there a push button switch that will allow you to hit it 3 times and on the 4th it will turn the circuit off? so the gear hits the switch and the circuit goes on and then when the gear hits the switch again the circuit stays on until the switch is activated 4 times?
    Probably a stupid question but I have been looking for switches online and I am in over my head. Thanks for any help.


  • Registered Users Posts: 14,011 ✭✭✭✭Johnboy1951

    1. Replace the switch with a mechanical gear that takes a few movements to operate a switch.

    2. Replace the switch with an electronic circuit that requires a few pulses to operate the output.

  • Registered Users Posts: 18 Fordie99

    2. Replace the switch with an electronic circuit that requires a few pulses to operate the output.

    Thanks Johnboy1951, This may sound lazy but I have a window of 5 days to fully complete this project. Is it possible to buy these circuits pre-made in the likes of Maplins or would I have to construct this myself?

    and are there push button switches similar to a toggle switch that has the following settings:
    1. off
    2. on for circuit 1
    3. on for circuit 2
    4. on for circuit 3

    Kind of like the toggle switches that cater for devices with different levels of intensity? so like level 1 has a certain resistance and 2 has less resistance etc. ?

  • Registered Users Posts: 14,011 ✭✭✭✭Johnboy1951

    I haven't used any such 'off the shelf' components, sorry.

  • Registered Users Posts: 9,455 ✭✭✭TheChizler

    Don't know if this has been sorted but the only thing I can remember from the Mechanical Engineering part of my course is a Geneva mechanism. Have the cam operate a four 'toothed' one of these and it in turn activate the switch.

    Is this some kind of Rube Goldberg machine you're building?

    You could very easily make an electronic counter using J-K flip flops if you have easy access to the components, but the complication is using this to power anything, you'd have to build a buffering device suited to the next stage.