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Current time:0:00Total duration:6:09

What is inside a hair dryer? (1 of 2)

Video transcript

all right today we're going to take a look at the Conair 1875 hairdryer we're going to look at the different systems and functions inside of it how it was made and how it works and we're also going to take a look at how they were able to produce a hairdryer for less than eight dollars and still make a profit still stay in business as a company because that's a very low price and the way they've done that is they've reduced a lot of cost and complexity we'll take a look at how they've done that so the first thing I want to take a look at is the plug here this is called a ground fault interrupter circuit plug and it has two different sized prongs right here there's a there's a larger prong and a smaller prong and that's very important the larger prong is the neutral prong and that means you can't plug this plug in incorrectly it has to go in only one way and that means that the power is grounded properly so the power always goes to ground and that's it that's a critical thing in a circuit like this and so what this plug does is it's it's actually pretty smart it can it can tell if there's a power difference between these two prongs and that power difference might occur when the hairdryer was say dropped in water or there was some sort of short that happened inside the hairdryer there are open electrical contacts that if there can put in into water or some other conductive fluid they will short out and it'll cause the you know it electrify the fluid and and in the past that was a huge problem because people would get shocked or electrocuted and now it's not as big a deal because we have these ground fault interrupter circuits so let's take a look at what's inside of that and I've already popped this apart to some degree I'm gonna see if I can't get it the rest of the way here now I want to say one thing really quick here from a safety standpoint it is absolutely critical that you don't take apart any plugs ever without a professional and if you if you do have a professional and you do end up taking apart a plug like this make sure that you never ever plug it in it's totally unsafe so this is a plastic molded housing it was injection molded there was two pieces of steel that came together and they they the molten plastic was injected and you can see there are little pin marks right here and pins came in inside the mold and push this part out and then there's a little plastic piece here with a spring and that's for the test switch so the tests which pushes on this part right here on the printed circuit board and the reset switches right here so you push on the reese wet set switch and it will reset it so if it gets triggered you can still use your hairdryer again later so one thing I want to take a look at here is the printed circuit board here so we've got a lot of really cool things happening on this printed circuit board it is made out of fiberglass it's got a thin layer of copper applied to it and then on top of the copper is a layer of lacquer the the copper before they put the lacquer layer down they actually etch away parts of the copper so there's places where there is no copper and there's places where there is and those places where the copper exists are called traces and they function like little tiny wires they're super flat and compact and allow you to get a lot of stuff in a very small space which is why we use a little printed circuit board like this and you can see on here we've got a little tiny capacitor that's called the surface mount capacitor and a little resistor remember capacitor stores a charge and then releases it and a resistor will resist current flow and that can be used to protect protect different parts of the circuit and this right here is this part right here is called an integrated circuit and it actually takes commands from things on the back it takes information from things on the back and decides what to do with it so this thing right here is called a toroidal ring or a copper coil and it it basically can sense the the difference between these two lines and so when there's a significant voltage difference of a few a few milliamps even it can tell and it sends information to the integrated circuit here and then the integrated circuit tells this guy which is a it's called a solenoid it's a linear solenoid but it sends electricity to this and it causes this pin to pop and when the pin pops the it breaks the circuit the electrical contact can connection in the circuit so there's no chance that you can get shocked there and there's a couple really neat and interesting parts on this board we've got a this is a dielectric capacitor and then we have another capacitor right here and you can see right here this is a ceramic capacitor this little sort of rust colored one it'll take this out so you can see it better and this is called a a transistor so it can function like a switch in a circuit and this is called a varistor or a variable resistor and it can protect the circuit from high voltages and things like that it's a it's a nonlinear resistor in other words as the current flow changes the resistance changes and so it can protect your circuitry there and if you look on the inside you can see the the backside of the plugs or there are the prongs I should say and those are just brass pieces with with the wires that go to the circuit soldered on and then this part of the of the switch housing is or I should say the plug is also made out of injection molded plastic and then we have a the wire that comes down here and there's this protective rubber piece on the wire so that the wire can flex back and forth inside of the housing without wearing out and if you look right here here's a warning it says unplug it do not remove this tag they still want to warn you that it's definitely not safe to drop a hair dryer in to water and this is a safety precaution but it's it's not a good idea to ever put the hair dryer near water because it is an electrical device with with open contacts on the inside