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Electrical engineering
Course: Electrical engineering > Unit 7
Lesson 1: All about Spout- 3rd graders build robots at Santa Rita Elementary School
- SPDT switch
- Spout's sliding SPDT switch
- Spout lights
- Spout motor
- Spout battery configuration and polarization
- Spout's reversing circuit and final assembly
- Spout circuit
- Rotary switched spout circuit
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Spout's sliding SPDT switch
Created by Karl Wendt.
Want to join the conversation?
- What does the switch do to help the robot?Does it turn it on and off?(5 votes)
- aton the next video, he answers your question... yes, it does 0:10(4 votes)
- At, why do you use this kind of switch? 0:35(2 votes)
- Hi Lancelot,
There are thousand's of application that can use the "single pole double throw" switch. Here are a few links to get you started:
https://en.wikipedia.org/wiki/Multiway_switching
https://learn.sparkfun.com/tutorials/switch-basics/poles-and-throws-open-and-closed
Regards,
APD(2 votes)
- Is the plastic switch 3D printed? Thanks(2 votes)
- how much power can the swich the swich handal(4 votes)
- Do you do damage to the item by bending it?(1 vote)
- Can you use a toggle switch?(1 vote)
- Why do people want robots to help us in the new world?(1 vote)
- what does the spout in the name of the video mean?(1 vote)
- Would the center lead be called the common?(1 vote)
- Is there a store where you can buy the SPDTswitch?(1 vote)
Video transcript
All right, so this
is our single pole double throw sliding switch. It's not a single
pole double throw lever switch, like the
switch we just took apart. It's a little different. So it's got a
plastic slider here, which goes back and forth. And it connects the power
between this contact and this contact or between
this contact and this contact. So this is called a
single pole double throw because there's
one pole in the center and there's two
throws on either side. So let's go ahead
and take it apart and see what it's made
out of and how it's made. The outer housing is
actually kind of ingenious. It's stamped steel
that's nickel plated. And what they've done is
instead of using screws or glue, they've just basically
taken a flat sheet of steel and bent it around
a bunch of times to hold everything together
and create a nice housing. This can be put on a
component circuit board and soldered in place to
turn things on and off. And it can be used
on our Spout bot, of course, to turn
the LEDs on and off and the motors on and off. So let's go ahead
and take it apart. The first thing we need to do
is these little tiny tabs here, we're going to try and
bend those out of the way. And I'm going to use
another pliers here because it's tricky
to get inside of this. Then hold it. So we're just going to
bend those little tabs out of the way. There we go. We'll go to the other side here. And it takes a little bit
to get the tabs bent out because they're itty bitty. But they're strong enough
to hold the switch in place. Almost got them. There we go. OK, so once you get the
tabs bent out of the way, you'll see that there
is a board here. It looks like an epoxy board. And it's got a few pieces of
aluminum sticking through. And if you look closely, you
can see there's three of those. And you can see that
the top, the one in the middle, the pole, it's
got a bit of a bump in it. And what that does,
that's important because that causes the switch
to slide into position so it doesn't stick between
the two positions. And let's see if we can
get this to come out here. So we've got probably
an ABS plastic slider. And then there's a little
metal slider inside of that, a little
metal piece that slides over the
contacts like this. Slides over those contacts. So when it's in this
position, these two-- sorry, let me see if I can get this
to where you can see it. Oh, there's the contact
that's popped out. Let's put that back in. There we go. So when it's in this position,
these two are connected. And when it's in this position,
these two are connected. So the power flows
between this circuit when it's in this
position and this circuit when it's in this position. Now, the way it
stays in contact is it's actually kind of an
ingenious little spring that's inside of here. So this is the part
that actually conducts the electricity between
the two connections here. And then there's a
spring inside of it. And what the spring does is it
pushes down on that contact. And that makes sure that
it stays firmly connected to the poles and throws. So it stays firmly
connected like that. And that's really
important because if you don't have that spring,
the contact may lift up, and then you may not
have consistent power. Now, one more thing is we're
actually using this switch as a single pole
single throw switch. Whoa, got away from me there. We're using this as a single
pole single throw switch. So we're not actually
using both of the throws. So we just bent this
throw out of the way, because we only needed
one of the throws. And the main reason why we're
using this switch for Spout is that we just got a
really good deal on it. You can find it for
about $0.05 online. So it's really
cheap, and it happens to do the job just fine.