air solenoid controller help

Discussion in 'The Projects Forum' started by drjekl, Jan 8, 2012.

  1. drjekl

    Thread Starter New Member

    Jan 8, 2012
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    Hello people, first post for me.

    i have minimal electronic knowledge, but i work as an auto electrician so I'm not completely in the dark about circuits.

    i would like some help to come up with a circuit diagram so i can build the device i need
    i need a device that will control some air solenoids

    my power source is 12volt DC

    my trigger input (input 1) will switch from +12v to 0v dc (it will go 0v to trigger then once triggered go back to 12v)

    when the device receives this trigger input it needs to control an air solenoid ( it can be a 12v output to power the air solenoid winding or it could ground the air solenoid winding either way is fine i haven't wired the solenoids yet)

    OK, so device has received 1 trigger and it has one solenoid in operation,

    the next trigger signal the device gets (still input 1) needs to now power up another air solenoid BUT also keep the first one powered

    i need a small delay from when first trigger is received until it recognizes the next trigger (about 1/2 a second) just in case the trigger accidentally 'bounces' for want of a better term.

    i need to operate 4 solenoids in this way, with every next solenoid it needs to keep the previous solenoid/s activated also.

    i will then need a way to reset the output back to the first (turning off all solenoids) but i guess i can just do this by switching off the 12v source.

    that will be the basic device i need.

    but if your feeling extra helpful it would be nice to have an option that when a signal (either +12v or 0V )is received via another input (input 2) it switches on the first two solenoid outputs and ignores the trigger on input 1, effectively overriding it.
    then on a third input (input 3) i would like a push button that when the signal is applied to input 2 the push buttons will allow you to select the last 2 solenoids ( push button once,one is applied (so 3 in total) push button again and the last is applied )
    but if the signal is not on input 2 the buttons on input 3 wont do anything
    and i will need a delay(again 1/2 second) on the push button input just in case i accidentally push the buttons to quick

    i must add the solenoids draw less than 1 amp when in operation, im unsure of what the peak is i haven't measured it but at a guess it wouldnt be more that 6amps @12v


    any help is greatly appreciated

    thank you,
    blair
     
    Last edited: Jan 8, 2012
  2. praondevou

    AAC Fanatic!

    Jul 9, 2011
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    Maybe tomorrow. :)


    The 40174 is positive edge triggered that's why your input needs to be inverted.

    [​IMG]
     
  3. Bernard

    AAC Fanatic!

    Aug 7, 2008
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    Here is an outline of a ckt that might work. When in 1 is pulsed from 1 to 4 times, shift register, SR, U4, will load consecutive highs on stages 1-4. Outputs pass thru OR gate U6 to solenoid drivers U7 1-4. If an input signal appears at #2 input, flip flop, FF, U3,is set, out notQ goes low, disabling U2-1 & SR U4. The input also goes thru OR gates U6-1&2, activating solenoids 1 & 2. If FF has not been reset,out Q is high, enabling U2-2, allowing input#3 push-button SW to advance counts on SR U5, activating solenoids 3 & 4 in sucession. Additional circuitry is needed to ensure reset at turn on.
     
  4. drjekl

    Thread Starter New Member

    Jan 8, 2012
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    thanks guys for taking some time to sketch me up a diagram, i really appreciate it.

    Bernard i have a few questions,

    the U1 -1,2,3 is an inverting schmitt trigger?
    the U2 - 1,2 are AND gates?
    the U6's are OR gates?
    the RE bits are for reset circuit?
    the U7's are an NPN?
    if these are all correct, i understand how it works and i will attempt to build it:)
    lastly, do you have a few part numbers for components (eg the shift register and the FF)i could use if its not to much trouble?

    Thanks again,
    Blair
     
  5. Bernard

    AAC Fanatic!

    Aug 7, 2008
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    U1 Non inverting, or two inverting in series. U2 AND, U6 OR, RE RESET, U7 N CH MOSFET.
    New print with numbers. An RS latch is used for the FF, see thumbnail. Some values & parts borrowed from praondevou's print. Power SW upper right, un labled SW2. C4, R5, make up power-up reset. If a SW reset is desired, parallel C4 with NO PB SW. Operation is same as before. Questions- just ask. Looks like you have it figured out pretty well.
     
  6. drjekl

    Thread Starter New Member

    Jan 8, 2012
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    eeekk now thats a bit more daunting for me, ill give it a go though.
    a massive appreciation for your efforts there Bernard!!


    i will head off and locate these components (ill probably get 3 times whats required just in case)

    once built ill share a picture of my efforts, plus what i am going to use it for.

    Thanks,
    Blair
     
  7. shortbus

    AAC Fanatic!

    Sep 30, 2009
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    I'm pretty sure its a air ride control for your car/truck. To make it dance like the guys with 'hydraulics', right? If so, got to be careful about pinching the bags in the A-arms and such.
     
  8. drjekl

    Thread Starter New Member

    Jan 8, 2012
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    Ha ha No sorry it's not for that.
    It's for a drag car The solenoids change gears. I'm using the engine
    Ecu to trigger at say 9000 rpm to shift gears. The other inputs will be so we can do a skid in the water traps in 3rd gear then shift up as we need.
    It's all to get to that elusive 6 second bracket for rotary engines here in new Zealand
     
  9. shortbus

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    Knew it was something for a car:) Didn't say anything earlier, so as not to trigger our TOS.
     
  10. Georacer

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    Nov 25, 2009
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  11. Georacer

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    Nov 25, 2009
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    On praondevou's comment, since a drag racer isn't exactly a road vehicle, I 'll discuss with the other mod's about this thread's reopening.

    The main reason is that since the OP didn't mention the car application on opening the thread, most of the suggestions are invalid for automotive application.
     
  12. Georacer

    Moderator

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    Ok, thread is open once again.
     
  13. drjekl

    Thread Starter New Member

    Jan 8, 2012
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    Sorry to all I just skim read the terms and conditions.
    I'm against illegal/unsafe modifications to vehicles and I'm guessing that is why they are taboo here. Thanks for seeing this topic in a different light, the car is a full drag car and only goes on 1/4 mile strip.

    Next question,
    Georacer what makes them invalid for automotive use?

    Thanks,
    Blair
     
  14. praondevou

    AAC Fanatic!

    Jul 9, 2011
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    In a car there are usually some components that create noise/transients on the power supply line (conducted). Radiated noise can also be a problem.

    I wonder if there would be a safety problem if the circuit doesn't work as intended. I don't know nothing about drag cars. Is there a scenario where if the circuit fails, e.g. changes the sequence of the solenoids wildly up and down? Wouldn't that be fatal? At least for the car?
     
  15. drjekl

    Thread Starter New Member

    Jan 8, 2012
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    At the moment with the manual air shift buttons if you miss pushing one in out of sequence all that happens is you miss the top gear. For instance if you miss the 3rd button you will only get to forth gear until you push in that last button even though it's not the 5th gear button you missed it stops it going to 5th. Shifting wildly will be an issue though and have effects on engine gearbox and diff. If day you were in 4th or 5th and it came back to 1st or 2nd.
    The cdi ignition and 16 injectors give out a lot of noise and we have had to run some wiring on opposite side of car and a lot of shielding so yer it is an issue.

    Any mods to Bernard's diagram to minimize these?

    Thanks again,
    Blair
     
  16. Bernard

    AAC Fanatic!

    Aug 7, 2008
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    Possible shanges for harsh environment:
    Mount in metal box
    Mount U5-U8 close to solenoids along with gate resistors, ground sources to a good solid ground.
    As a last resort, add a non inverting buffer to 4071 outputs, something like DS1630, or limited temp model DS3630.
    Use shiielded leads for gate lines??
    Use wide temp versions of IC's, CD40106BM, CD4093BM, CD4015M, CD4071BM
    Look for suggestions from someone familiar with automotive electronics.
     
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