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Correct name for push button switch

Tyler Monk

Feb 27, 2017
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Feb 27, 2017
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Hi,
I am struggling to find the name of the switch I require, and it may not even exsist, hopefully you guys can help.
I'm looking for a momentary switch that completes on circuit when released and other one when pressed.
Hope you can help

Cheers
Tyler
 

donkey

Feb 26, 2011
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momentary double pole double throw?
momentary single pole double throw?
momentary defines that you have to hold down the button to complete A connection
double pole/ single pole is how many circuits you can have
double throw means it connects to 1 device then other. triple throw would connect to 3 items

the only thing I would say is make sure there isn't an off

https://www.jaycar.com.au/dpdt-quality-pushbutton/p/SP0714 dpdt
https://www.jaycar.com.au/sub-mini-pushbut-spdt-mom-hori-r-a-pcb-s/p/SP0380 spdt
 

Tyler Monk

Feb 27, 2017
5
Joined
Feb 27, 2017
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Hi guys, thanks for your effort in finding the switch I require. However I still cannot find the one I need. I have two circuits and this switch has to cater to them both. Here is what I'd like it to accomplish

Be momentary, no latching

While the button in in its resting position circuit A is closed and connected, and circuit B is disconnected.

When the button is pressed circuit A is disconnected, and circuit B is then connected

Hope this is clear, I'm finding it difficult to understand myself to be honest.
 

CDRIVE

Hauling 10' pipe on a Trek Shift3
May 8, 2012
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You're describing a DPDT (PB) switch. Like this.....

Chris
upload_2017-3-21_20-53-31.png
 

donkey

Feb 26, 2011
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A double pole double throw or dpdt momentary will do the same when wired correctly
 

73's de Edd

Aug 21, 2015
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Sir Tyler Monk . . . . . . . .

Lets now compare and evaluate and see egg-zackly what switch action you need.
From what can I perceive from your initial given information of :

Be momentary, no latching

That is where the spring loaded comes into play . . . . it only engages . . . for however short or long of time that you push and hold in the button.

While the button in in its resting position circuit A is closed and connected, and circuit B is disconnected.

In the provided graphics the A circuit function normally has a short between 2 and 3 terminals , while B circuit has an open connection. This fullfills the above circuit conditions . . . .when untouched.

When the button is pressed circuit A is disconnected, and circuit B is then connected

This is done by the item 8 pushbutton end pressing in pin 12 which starts compressing 11 spring and the pin 12 other end starts its entry into a slightly off centered divot on a pivoting cantilever as GREEN 7, it starts moving CW and moves a spring loaded ball bearing 5 incrementally towards the RED dot position. As the bearing passes the red dot, it has passed a balance point and the spring loaded bearing shortly flips the switch contact to short between 1 and 2 terminals while disconnecting from prior 3 terminal. The ball bearing is now left resting in a like position on the other side of the RED dot.
Exploded view . . . . au . . . . . Switch Electro-Mechano Action . . . . .

KK1xmPc.png



Hope this is clear, I'm finding it difficult to understand myself to be honest.

Me too !

This was accomplished with the PINK REFERENCED SPDT switch IF a common wire can be shared.
If you need a single wire connection to be made and broken at A circuit and the same at B circuit but with NO sharing of wires you would use the drawn BLUE REFERENCED DPDT configuration where you have two wires coming in to pins 3 and 2 of A for a short between those two wires.
You then use another two wires coming in to B prime pins 1 and 2 where you would have an open circuit until you push the switch

NOW if you did not need that self choice time of auto returning push switch, you would need what is called a push-push switch where its two switched states alternate each time you fully press in on the switch and then release it.
Also not given was the power and voltage reqirements needed to be switched.
Also any physical size limitations.

What say you . . . . . .

http://i.imgur.com/KK1xmPc.png


73s de Edd
 
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(*steve*)

¡sǝpodᴉʇuɐ ǝɥʇ ɹɐǝɥd
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Jan 21, 2010
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Switches with one normally open set of contacted and one normally closed set of contacted are common in E-stop buttons (although these normally latch)

I'm sure I've seen non latching switches of this nature...

Here is a page of them from Digikey. They're described as "DPST (1 NO, 1 NC)"
 
Last edited:

BobK

Jan 5, 2010
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Pricey little buggers, aren't they?

Bob
 

(*steve*)

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Probably much cheaper to purchase a DPDT momentary contact switch and just use the contacts you need.
 

Tyler Monk

Feb 27, 2017
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Feb 27, 2017
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Guys...... thanks for all your assistance, got what I need now I got a DPDT switch and used that, works a treat. Thanks again fellas
 

Tyler Monk

Feb 27, 2017
5
Joined
Feb 27, 2017
Messages
5
.

Sir Tyler Monk . . . . .
. . .

Lets now compare and evaluate and see egg-zackly what switch action you need.
From what can I perceive from your initial given information of :

Be momentary, no latching

That is where the spring loaded comes into play . . . . it only engages . . . for however short or long of time that you push and hold in the button.

While the button in in its resting position circuit A is closed and connected, and circuit B is disconnected.

In the provided graphics the A circuit function normally has a short between 2 and 3 terminals , while B circuit has an open connection. This fullfills the above circuit conditions . . . .when untouched.

When the button is pressed circuit A is disconnected, and circuit B is then connected

This is done by the item 8 pushbutton end pressing in pin 12 which starts compressing 11 spring and the pin 12 other end starts its entry into a slightly off centered divot on a pivoting cantilever as GREEN 7, it starts moving CW and moves a spring loaded ball bearing 5 incrementally towards the RED dot position. As the bearing passes the red dot, it has passed a balance point and the spring loaded bearing shortly flips the switch contact to short between 1 and 2 terminals while disconnecting from prior 3 terminal. The ball bearing is now left resting in a like position on the other side of the RED dot.
Exploded view . . . . au . . . . . Switch Electro-Mechano Action . . . . .

KK1xmPc.png



Hope this is clear, I'm finding it difficult to understand myself to be honest.

Me too !

This was accomplished with the PINK REFERENCED SPDT switch IF a common wire can be shared.
If you need a single wire connection to be made and broken at A circuit and the same at B circuit but with NO sharing of wires you would use the drawn BLUE REFERENCED DPDT configuration where you have two wires coming in to pins 3 and 2 of A for a short between those two wires.
You then use another two wires coming in to B prime pins 1 and 2 where you would have an open circuit until you push the switch

NOW if you did not need that self choice time of auto returning push switch, you would need what is called a push-push switch where its two switched states alternate each time you fully press in on the switch and then release it.
Also not given was the power and voltage reqirements needed to be switched.
Also any physical size limitations.

What say you . . . . . .

http://i.imgur.com/KK1xmPc.png


73s de Edd

.
You sir, should be a teacher, cheers dude very helpful
 
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