WEBVTT 00:00:01.749 --> 00:00:04.072 Alright today we're going to take a look at the NOTE Paragraph 00:00:04.087 --> 00:00:06.976 Conair 1875 hair dryer.We're going to look at the different systems 00:00:06.976 --> 00:00:09.171 and functions inside of it, how it was made and 00:00:09.187 --> 00:00:12.089 how it works. 00:00:12.090 --> 00:00:14.657 And we're also going to take a look at how they 00:00:14.718 --> 00:00:17.340 were able to produce a hair dryer for less than 00:00:17.340 --> 00:00:19.864 $8.00 and still make a profit and still stay in 00:00:19.864 --> 00:00:22.134 business as a company because that's a very low 00:00:22.134 --> 00:00:24.210 price and the way low price. And the way they've 00:00:24.210 --> 00:00:27.072 done that is they've reduced a lot of cost and 00:00:27.072 --> 00:00:29.127 complexity and we'll take a look at how they've 00:00:29.127 --> 00:00:31.107 done that. So the first thing I want to take a look at is 00:00:31.107 --> 00:00:33.453 the plug here. This is called a "ground fault 00:00:33.469 --> 00:00:36.047 interruptor circuit plug" and it has two different 00:00:36.047 --> 00:00:38.048 sized prongs right here. There's a larger prong and 00:00:38.048 --> 00:00:40.102 a smaller prong. And that's very important. 00:00:40.117 --> 00:00:42.309 The larger prong is the neutral prong and that 00:00:42.309 --> 00:00:44.905 means you can't plug this in incorrectly, it has to go in 00:00:44.905 --> 00:00:47.642 in only one way. And that means that the power 00:00:47.642 --> 00:00:52.265 is grounded properly. So the power always goes 00:00:52.265 --> 00:00:55.737 to ground and that's a critical thing in a circuit 00:00:55.737 --> 00:00:59.082 like this. So what this plug does it's actually pretty 00:00:59.082 --> 00:01:02.339 smart it can tell if there's a power difference 00:01:02.339 --> 00:01:04.605 between these two prongs. And that power difference 00:01:04.605 --> 00:01:07.410 might occur when the hair dryer was, say, dropped 00:01:07.410 --> 00:01:10.543 in water or there was some sort of short that 00:01:10.543 --> 00:01:13.846 happened. Inside the hair dryer there are open 00:01:13.846 --> 00:01:16.539 electrical contacts that if they're put into water 00:01:16.539 --> 00:01:20.565 or some other conductive fluid they'll short out. 00:01:20.565 --> 00:01:23.437 And it will cause the, you know, it'll electrify the fluid. 00:01:23.437 --> 00:01:26.011 And in the past that was a huge problem because 00:01:26.028 --> 00:01:28.668 people would get schocked or electrocuted and now 00:01:28.668 --> 00:01:30.856 it's not as big a deal because we have these ground 00:01:30.856 --> 00:01:33.623 fault interruptor circuits. So let's take a look at what's 00:01:33.623 --> 00:01:35.842 inside of that. And I've already popped this apart to NOTE Paragraph 00:01:35.842 --> 00:01:38.402 some degree. I'm going to see if I can get it the rest NOTE Paragraph 00:01:38.402 --> 00:01:40.832 of the way here. Now I want to say one thing really NOTE Paragraph 00:01:40.832 --> 00:01:44.499 quick here from a safety stand point: 00:01:44.514 --> 00:01:49.113 It's absolutely critical that you DON'T take apart 00:01:49.113 --> 00:01:52.424 any plugs ever without a professionnal! And if you do 00:01:52.424 --> 00:01:56.735 have a professional and you do end up taking apart 00:01:56.735 --> 00:02:01.638 a plug like this make sure that you never ever 00:02:01.638 --> 00:02:04.550 plug it in! It's totally unsafe. So this is a plastic 00:02:04.550 --> 00:02:08.256 moulded housing it was injection moulded. 00:02:08.256 --> 00:02:11.798 There were two pieces of steel that came together 00:02:11.798 --> 00:02:15.084 and the molten plastic was injected and you can see 00:02:15.084 --> 00:02:17.457 there are little pin marks right here. And pins came in 00:02:17.457 --> 00:02:20.081 inside the mold and pushed this part out. 00:02:20.081 --> 00:02:21.936 And then there's a little plastic piece here with a 00:02:21.936 --> 00:02:23.496 spring and that's for the test switch. 00:02:23.496 --> 00:02:25.480 So the test switch pushes on this part right here 00:02:25.480 --> 00:02:29.140 on the printed circuit board and the reset switch 00:02:29.151 --> 00:02:31.339 is right here. So you push on the reset switch 00:02:31.339 --> 00:02:33.757 and it will reset it so if it gets triggered you can still 00:02:33.757 --> 00:02:38.028 use your hair dryer again later. 00:02:38.028 --> 00:02:42.473 So one thing I want to take a look at here is the 00:02:42.473 --> 00:02:46.100 printed circuit board here. So we've got a lot of 00:02:46.100 --> 00:02:48.496 really cool things happening on this printed circuit 00:02:48.496 --> 00:02:51.665 board. It is made out of fiberglass. 00:02:51.665 --> 00:02:53.851 It's got a thin layer of copper applied to it. 00:02:53.851 --> 00:02:56.493 And then on top of the copper is a layer of lacquer. 00:02:56.493 --> 00:02:58.912 (The copper) Before they put the copper layer down 00:02:58.912 --> 00:03:01.153 they actually etch away parts of the copper. So 00:03:01.153 --> 00:03:03.063 there's places where there is no copper and there's 00:03:03.063 --> 00:03:05.423 places where there is. And those places where the 00:03:05.423 --> 00:03:07.570 copper exists are called traces and they function 00:03:07.570 --> 00:03:10.255 like little tiny wires. They're supper flat and compact 00:03:10.255 --> 00:03:12.952 and allow you to get a lot of stuff in a very 00:03:12.952 --> 00:03:15.690 small space. Which is why we use a little 00:03:15.690 --> 00:03:18.570 printed circuit board like this. And you can see on 00:03:18.570 --> 00:03:21.444 here we've got a little tiny capacitor that's called a 00:03:21.444 --> 00:03:24.468 surface mount capacitor and a little resistor. 00:03:24.468 --> 00:03:27.045 Remember a capacitor stores a charge and then 00:03:27.045 --> 00:03:29.489 releases it and a resistor will resist current flow 00:03:29.489 --> 00:03:32.172 and that can be used to protect different parts of the 00:03:32.172 --> 00:03:34.082 circuit. And this right here is 00:03:34.082 --> 00:03:39.553 this part right here is called and integrated circuit. 00:03:39.553 --> 00:03:43.572 And it actually takes commands from things on the 00:03:43.572 --> 00:03:47.788 back takes information from things on the back 00:03:47.788 --> 00:03:51.856 and decides what to do with it. 00:03:51.856 --> 00:03:56.239 So this thing right here is called a toroidal ring 00:03:56.239 --> 00:03:59.551 or a copper coil and it basically can sense the 00:03:59.551 --> 00:04:02.437 difference between these two lines. 00:04:02.437 --> 00:04:04.959 And so when there's a significant voltage difference 00:04:04.959 --> 00:04:07.773 a few milliamps even 00:04:07.773 --> 00:04:10.219 it can tell and it sends information to the 00:04:10.219 --> 00:04:13.966 integrated circuit here. And then the integrated circuit 00:04:13.966 --> 00:04:19.219 tells this guy which is called a solenoid 00:04:19.219 --> 00:04:22.613 it's a linear solenoid. 00:04:22.613 --> 00:04:26.352 But it sends electricity to this and it causes this pin 00:04:26.352 --> 00:04:28.905 to pop. And when the pin pops, it breaks the circuit 00:04:28.905 --> 00:04:31.296 the electrical contact, the connection in the circuit. 00:04:31.296 --> 00:04:33.810 So there's no chance that you can get shocked there. 00:04:33.810 --> 00:04:36.320 And there's a couple of really neat interesting parts 00:04:36.320 --> 00:04:38.702 on this board. We've got a 00:04:38.702 --> 00:04:41.023 this is a dialectric capacitor. 00:04:41.023 --> 00:04:43.635 And then we have another capacitor right here. 00:04:43.635 --> 00:04:46.226 And you can see right here this is a ceramic 00:04:46.226 --> 00:04:48.622 capacitor this little sort of rust colored one. 00:04:48.622 --> 00:04:51.199 I'll take this out so you can see it better. 00:04:51.199 --> 00:04:54.347 And this is called a transistor so it can function 00:04:54.347 --> 00:04:58.540 like a switch in a circuit. And this is called a 00:04:58.540 --> 00:05:03.127 varistor or a variable resistor and it can protect the 00:05:03.127 --> 00:05:08.444 circuit from high voltages and things like that. 00:05:08.444 --> 00:05:11.666 It's a non-linear resistor in other words as the 00:05:11.666 --> 00:05:14.215 current flow changes the resistance changes and so 00:05:14.215 --> 00:05:16.394 it can protect your circuitry there. 00:05:16.394 --> 00:05:21.827 And if you look on the inside you can see the 00:05:21.827 --> 00:05:25.070 back side of the plugs or the prongs I should say. 00:05:25.070 --> 00:05:27.571 And those are just brass pieces with wires that 00:05:27.571 --> 00:05:30.184 go to the circuit soldered on. 00:05:30.184 --> 00:05:33.659 And then this part of the switch housing 00:05:33.659 --> 00:05:36.896 or I should say the plug is also made out of injection 00:05:36.896 --> 00:05:40.162 moulded plastic. And then we have the wire that 00:05:40.162 --> 00:05:42.572 comes down here and there's this protective rubber 00:05:42.572 --> 00:05:45.092 piece on the wire so that the wire can flex back-and- 00:05:45.092 --> 00:05:47.801 forth inside of the housing without wearing out. 00:05:47.801 --> 00:05:50.328 And if you look right here here's a warning. It says: 00:05:50.328 --> 00:05:53.423 unplug it do not remove this tag. 00:05:53.423 --> 00:05:55.963 They still want to warn you that it's definitely not safe 00:05:55.963 --> 00:05:58.972 to drop a hair dryer into water. 00:05:58.972 --> 00:06:01.864 This is a safety precaution but it's not a good idea 00:06:01.864 --> 00:06:04.761 to ever put the hair dryer near water because 00:06:04.761 --> 00:06:07.098 it is an electrical device with open contacts 00:06:07.098 --> 00:06:07.965 on the inside.