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12V push button 2 way switch

PostPosted: 13 Nov 2020, 10:17
by Mike G
Does anyone have a suggestion for a UK supplier for a 12V push button (on-on) 2 way switch. I can find them on Ebay but they come from China, and might not be here for a couple of months.

Re: 12V push button 2 way switch

PostPosted: 13 Nov 2020, 11:00
by Robert
My first option would be CPC farnell as their delivery costs are reasonable. https://cpc.farnell.com/

I haven't used RS components for years but their stuff was always quality though never that cheap https://uk.rs-online.com/web/

You need to know the current rating more than the voltage as you can always get a higher voltage rating but may have more trouble getting one that can handle enough current. Push buttons are usually momentary - only change while pushed but you can get latching types too.

If you are switching a heavy current you may need to use a relay in combination with the switch. That may also simplify things if you need DPDT rather than SPDT as double pole double throw will be a rare beast.

Re: 12V push button 2 way switch

PostPosted: 13 Nov 2020, 11:29
by Doug

Re: 12V push button 2 way switch

PostPosted: 13 Nov 2020, 11:54
by Mike G
I've tried 12V Planet, Doug, without luck.

Thanks Robert.

Re: 12V push button 2 way switch

PostPosted: 13 Nov 2020, 12:03
by sunnybob
assuming you mean on / off;
https://www.amazon.co.uk/12-Volt-Switch ... olt+Switch

if you really mean on / on, then you need to explain exactly what you want to do because thats not a normal item.

Re: 12V push button 2 way switch

PostPosted: 13 Nov 2020, 12:15
by AJB Temple
I've had 2 way rocker types from RS Mike. Push to on, centre off, push the other way for on.

It might be worth trying companies that deal with motor factors (cars) as that type of switching is sometimes used for things like mirror controls.

Re: 12V push button 2 way switch

PostPosted: 13 Nov 2020, 12:30
by Mike G
That would be an awkward-type compromise, Adrian, but a possible fall back position if I can't find a straight push-button switch.

This is a very unusual application, in that I want to be able to push a part of a carving to activate a TV raising and lowering mechanism. It has to be two way, because the mechanism will need to switch off at the end of each run, up or down. So whether the TV is up or down, I want to be able to push the button and have it go in the opposite direction to the way in which it last traveled. I can do it with a toggle switch, but I'd have to come up with some sort of reciprocating linkage, which I'd rather avoid.

Re: 12V push button 2 way switch

PostPosted: 13 Nov 2020, 12:55
by sunnybob
youre looking for a garage door roll up auto closer unit. the unit has sensors that reverses the current each time the button is pressed.

https://www.amazon.co.uk/Chamberlain-Pr ... B00EYYAHI8

Re: 12V push button 2 way switch

PostPosted: 13 Nov 2020, 12:57
by AJB Temple
I wondered if that was the case. I wonder if a twin push button car mirror or window switch could be rigged to do this. It's a common set up where a push button diverts the current to a left switch or a right switch - similar to a car window actuator which with a single press sets the window in motion and stops the travel at the end of the lift or lower. TV = car window.

Just trying to think of a solution.

Adrian

Re: 12V push button 2 way switch

PostPosted: 13 Nov 2020, 13:11
by Mike G
Well I've already got the switch which alters the spin direction of the motor, and I've designed a simple mechanical link to push this at the end of each "trip", after the circuit is switched off. The stop switch is also easy, so it's just the start switch which I need to solve.

Yes, Bob, it's precisely the same principle as a garage door opener, but I think they're either 240V (the manual switch on the wall) or operated by remote.

Re: 12V push button 2 way switch

PostPosted: 13 Nov 2020, 13:38
by Robert
If you are not looking to actually press the button with your finger then you are better off looking at microswitches.

All sorts of current ratings and configurations.

Still think you'll need a relay involved and you will need more microswitches as limit switches I'd have thought.

Re: 12V push button 2 way switch

PostPosted: 13 Nov 2020, 14:30
by Mike G
Microswitches........but...........but..........they're for people who know what they're doing........ :lol:

Re: 12V push button 2 way switch

PostPosted: 13 Nov 2020, 15:01
by sunnybob
I'd rather play with micro switches than chisels. :shock: :lol:
Or you could always use the right tools for the job
https://www.hiddentvlift.co.uk

Re: 12V push button 2 way switch

PostPosted: 13 Nov 2020, 15:11
by AJB Temple
:D :D You do know this is Mike, SB? He is making it. For peanuts. Same principle as your search for shellac. :lol:

Re: 12V push button 2 way switch

PostPosted: 13 Nov 2020, 15:23
by Mike G
Where's the fun in just buying a TV lift? I've got some wood, some wire, an old cordless drill, and plenty of time......

Re: 12V push button 2 way switch

PostPosted: 13 Nov 2020, 15:48
by sunnybob
I fully understand doing stuff on the cheap. its been my life's work.
But there comes a time.... and if this is a posh set up in a posh house, youre not going to be happy when it whines and creaks and jams and you have to take it all apart to oil it twice a year to stop the cable snapping leaving it just like the duke of york's army..
The other half will withhold affection, you can count on it. 8-)

Re: 12V push button 2 way switch

PostPosted: 13 Nov 2020, 16:36
by Mike G
It'll not only work, Bob, but work properly for years. There's no reason that homemade stuff can't be every bit as good as stuff made in a factory. It's no about doing it on the cheap.......it's about doing it.

Re: 12V push button 2 way switch

PostPosted: 26 Nov 2020, 23:07
by Richard39
As Robert said, worry less about the voltage rating and more about the current. Finding switches than can handle more than 12 volts is a doddle, but 12 volt switches are often designed to handle the higher currents that come with lower voltages. Do you know what current is needed to run through it?

Personally I'd probably be installing a relay to switch the main circuit and leave the switch to handle the low current required to switch the relay as it will ensure the switch works perfectly for a very long time, and give you a much greater choice of switches to choose from.

Re: 12V push button 2 way switch

PostPosted: 27 Nov 2020, 08:12
by Mike G
The current is 10amps, max, although it is unlikely that the motor will draw anything like that. I have acquired some 2 way micro-switches, so those will be my first approach, albeit I have some toggle switches as well. Here is how it will work with a toggle switch:

Image

The thing in the middle is a push-to-open cabinet door catch, which will give me the two positions I need, so I'll just push the carving and the TV will pop up. I'll have to do a quick sketch to work out how it works with micro-switches.

Re: 12V push button 2 way switch

PostPosted: 27 Nov 2020, 09:50
by novocaine
not got time now, about to go in to a design meeting.

you could do this digitally rather than analogue, it's only a change of state on a single push button. use a pair of relays to drive the motor.

Re: 12V push button 2 way switch

PostPosted: 27 Nov 2020, 19:57
by Mike G
novocaine wrote:.....you could do this digitally rather than analogue, it's only a change of state on a single push button. use a pair of relays to drive the motor.


:D How do I put this?

You may be over-estimating my electronics abilities by quite some margin. You're suggesting electronic fuel injection when I'm at the "is this the carb?" level.......

Re: 12V push button 2 way switch

PostPosted: 27 Nov 2020, 22:24
by DaveL
I did suggest to Mike that a relay, or maybe two would be an easy way to do it, but he wants to try it with just switches. Let's see how it goes, I can always visit to sort out relays later if required.

Re: 12V push button 2 way switch

PostPosted: 28 Nov 2020, 08:03
by Andyp
As I am sure you well know Mike, I am no expert in electrikery but even I got a relay to work.

Re: 12V push button 2 way switch

PostPosted: 28 Nov 2020, 08:36
by Mike G
The thing is, I can't really see what a relay brings to the party. I need to switch the motor off at each end of the platform's travels. So I use a switch...a simple 2 way switch. A relay is a switch, but switching another switch. Why add the complication?

Anyway, I won't get that far this weekend. Hopefully I'll get the bulk of the woodwork finished so I can start on the mechanism next week........so you've got a week or two to persuade/ educate me. :)

Re: 12V push button 2 way switch

PostPosted: 28 Nov 2020, 09:03
by novocaine
You add the relay so you can have a flip flop state change. Push once it goes up push again and it goes down. The issue i cant figure is the 3 states up,off,down. But leave it with me.

Just like you asked for.