Can a button open a circuit?

[dougburnett]

Buttons always close a circuit. But are there buttons that open a circuit? Here's what I'm trying to do:

I'm making an art installation that has an array of fake usb ports (just the raw materials, not functional, not powered). When I insert a USB drive into the fake port, I want to stop the sound that is going to a speaker. Is this (image above) the best way to accomplish this? I've never seen a button like this before. Trying to avoid needing a circuit board for each port since I need to do this for 250 ports.

Thanks for any help you can give.

 

[Colin Mitchell]

Put a spike on the end of the USB device and press on a switch that opens when pressed.

They are also called pin switches for inserting into a door for an alarm

 

[Gryd3]

Buttons always close a circuit. But are there buttons that open a circuit? Here's what I'm trying to do:

I'm making an art installation that has an array of fake usb ports (just the raw materials, not functional, not powered). When I insert a USB drive into the fake port, I want to stop the sound that is going to a speaker. Is this (image above) the best way to accomplish this? I've never seen a button like this before. Trying to avoid needing a circuit board for each port since I need to do this for 250 ports.

Thanks for any help you can give.

Take a look at button and switch terminology.
There is 'normally open' and 'normally closed' switches and buttons.

What you want to do is buy a 'normally closed' button. When the button is pressed, it goes 'open'. problem solved.

 

[dougburnett]

Wow! I'm glad it was that simple of a solve. Thanks a bunch. Do you mind checking my work on this? Am I thinking this through correctly? Here is one of the USB array panels from the art installation:

One iPod Shuffle sends two separate mono audio signals to each side of the panel. I daisy chain each of the normally closed buttons and connect the last one in the line to a 2W speaker. I'm not sure where I would but the Ground wire though.

When someone inserts the USB drive into the USB port, it pushes the normally closed button so that it opens the circuit, and disconnects the iPod signal from the speaker.

These are the buttons:
https://www.parts-express.com/momentary-nc-classic-small-push-button-switch-black--060-634

And these are the speakers:
https://www.parts-express.com/2-round-frame-mini-speaker-16-ohm--289-131

And if it helps to understand what I'm trying to do, this is what it looks like on the front side:

Thanks so much for any advice you can give.

 

[Gryd3]

Wow! I'm glad it was that simple of a solve. Thanks a bunch. Do you mind checking my work on this? Am I thinking this through correctly? Here is one of the USB array panels from the art installation:

One iPod Shuffle sends two separate mono audio signals to each side of the panel. I daisy chain each of the normally closed buttons and connect the last one in the line to a 2W speaker. I'm not sure where I would but the Ground wire though.

When someone inserts the USB drive into the USB port, it pushes the normally closed button so that it opens the circuit, and disconnects the iPod signal from the speaker.

These are the buttons:
https://www.parts-express.com/momentary-nc-classic-small-push-button-switch-black--060-634

And these are the speakers:
https://www.parts-express.com/2-round-frame-mini-speaker-16-ohm--289-131

And if it helps to understand what I'm trying to do, this is what it looks like on the front side:

Thanks so much for any advice you can give.

Looks good to me.
The 'ground' is simply the negative of the speakers... and if you are using a headphone jack, there is a tip, ring and sleeve.
The sleeve is 'ground' . You can run that wire however you see fit.
Please note that because of *how* the wire is run. take special care not to runt the speaker wire or groun wire parallel to a power source or other noisy gear or you may pick up noise.

 

[zms]

Wow! I'm glad it was that simple of a solve. Thanks a bunch. Do you mind checking my work on this? Am I thinking this through correctly? Here is one of the USB array panels from the art installation:

One iPod Shuffle sends two separate mono audio signals to each side of the panel. I daisy chain each of the normally closed buttons and connect the last one in the line to a 2W speaker. I'm not sure where I would but the Ground wire though.

When someone inserts the USB drive into the USB port, it pushes the normally closed button so that it opens the circuit, and disconnects the iPod signal from the speaker.

These are the buttons:
https://www.parts-express.com/momentary-nc-classic-small-push-button-switch-black--060-634

And these are the speakers:
https://www.parts-express.com/2-round-frame-mini-speaker-16-ohm--289-131

And if it helps to understand what I'm trying to do, this is what it looks like on the front side:

Thanks so much for any advice you can give.

does this mean that in order to make the speakers work again, all the USB drives will have to be removed first.

 

[dougburnett]

@zms yes, that's the big downfall. My thinking was after someone inserts a USB in, the attendant will pull it out halfway, closing the circuit again. There are 12 different circuits all running different audio.

Is there a way to wire this that each USB port in the circuit functions independent of each other, but still has the same audio source and speaker output?

 

[Gryd3]

does this mean that in order to make the speakers work again, all the USB drives will have to be removed first.

Yes. *ALL* switches in series must be *closed* to hear audio for the chosen speaker. So all USB ports must be removed or partially removed.

@zms yes, that's the big downfall. My thinking was after someone inserts a USB in, the attendant will pull it out halfway, closing the circuit again. There are 12 different circuits all running different audio.

Is there a way to wire this that each USB port in the circuit functions independent of each other, but still has the same audio source and speaker output?

I'm not sure I follow...
With the idea posted above, you have 4 options:
- Option 1. Normally Open, Series
--- ALL USB devices must be inserted for audio to play. Remove *any* 1 to stop audio.

- Option 2. Normally Open, Parallel
--- *Any* one USB device inserted will play audio. *All* USB devices must be removed to stop audio.

- Option 3. Normally Closed, Series
--- ALL USB devices must be removed for audio to play. Insert *any* 1 to stop audio.

- Option 4. Normally Closed, Parallel
--- *Any* one USB device can be removed to play audio. *All* USB device must be inserted to stop audio.


If you want finer grain control... you will need to look into some other form of logic...
How *exactly* do you want the whole thing to function?

 

[dougburnett]

Thanks for the reply. There are 6 replicates of the panel I posted above. Each has two circuits, making 12 circuits. Currently, if there are no USBs in the ports, all 12 circuits play audio, since I am using normally closed buttons. If someone inserts a USB, than one of those circuits stops playing, because that circuit is opened. In order to open the circuit again, the attendant will pull out the USB drive just far enough that it closes the circuit again.

Since I absolutely need the audio in that circuit to stop the moment someone puts in *any* USB drive, I think the only option I have is Option 3 Normally Closed, Series.

Is that correct logic?

 

[Gryd3]

Thanks for the reply. There are 6 replicates of the panel I posted above. Each has two circuits, making 12 circuits. Currently, if there are no USBs in the ports, all 12 circuits play audio, since I am using normally closed buttons. If someone inserts a USB, than one of those circuits stops playing, because that circuit is opened. In order to open the circuit again, the attendant will pull out the USB drive just far enough that it closes the circuit again.

Since I absolutely need the audio in that circuit to stop the moment someone puts in *any* USB drive, I think the only option I have is Option 3 Normally Closed, Series.

Is that correct logic?

Yessir.
Normally Closed buttons all strung together will cause the audio to stop as soon as any *one* USB device is fully inserted.
Of course. If you have 6 of those panels and 12 speakers then you need a little extra help if you want *all* of the speakers to stop at the same time.

Are you familiar with Relays?
Do a quick search for a 'Double Pole' Relay.
The idea I am bringing up here is that the USB devices will trigger a relay instead. You can trigger multiple relays at the same time if you want all 6 boards to be linked together.

 

[dougburnett]

Thanks. Sorry, I actually meant that I absolutely need the audio in that particular circuit to shut off. I actually really want the other ones to continue (assuming they haven't already been shut off).

Double Pole relays are fascinating. I'd like to use those in a future project.

Thanks for your help!

 

[Gryd3]

Thanks. Sorry, I actually meant that I absolutely need the audio in that particular circuit to shut off. I actually really want the other ones to continue (assuming they haven't already been shut off).

Double Pole relays are fascinating. I'd like to use those in a future project.

Thanks for your help!

Then you already have it figured out
Let u
s know if you need more help

 

[BobK]

Another possibility, with a small amount of electronics, is to have the music stop when any USB drive is inserted, then resume automatically after some time period.

Bob