Toaster

=Toaster= grichmond12toc

Most modern homes have toasters. Some would be lost without their toaster in the morning. It's a simple way to enhance a previously bland breakfast. I'm sure that many know, toasters toast. Usually, they toast bread. Other times they receive bagels, or muffins to toast. Even waffles can be toasted now a days. Plus, with advances in toasters, toaster ovens have been created to cook all sorts of food. Here is a simple explanation of a complex machine.

Purpose
//What is the fundamental purpose of the device?//
 * Toasters heat food (or anything put inside) to enhance the flavor.

Energy
//What energy transformations are seen in its operation?//
 * Toasters convert electrical energy, which they take from the "power grid", into heat, more specifically infrared radiation. The energy is transformed through wires.

Controls
//What sensors/controls are designed into the device?//
 * There is a **timer** and a **thermostat** that are both connected to shut off the toaster at the desired time.

The **timer** is set according to how much toasting is desired. The more toasted, the "dark" setting, sets the timer for longer, and the less toasted, the "light" setting, sets the timer for less.

The **thermostat** monitors the temperature inside the toaster. Depending on the setting (dark, medium, or light), the thermostat shuts off the toaster at the appropriate time to avoid burning.
 * This is a newer control on the toaster. Previously, toasters only had timers. This meant that when the toaster was first turned on, it would take some time to heat up, but if another piece of toast was put in after, it would be too hot and burn. The burning occurred because both when the toaster was cold and when the toaster was hot, the toast was left in the same amount of time.
 * The **timer** and **thermostat** control the power of the toaster through an electromagnet. A variable resistor or a bi-metallic strip on older models cut off the current to the electromagnet, therefore terminating the power. [[image:temperature_control.jpg width="435" height="327" align="right"]]
 * The **variable resistor** uses the "dark", "medium", and "light" controls as its variables. The dark is at one end of the spectrum, and the light at the other end. Depending on the setting chosen, more or less resistance will be created. The more resistance, the less electricity, the less the machine will toast. This is a newer design feature which gives a more accurate toast.
 * The **bi-metallic strip** bends as it heats, breaking the current flowing between the electromagnet and the power source. When the power turns off, the electromagnet is no longer magnetized. The electromagnet is the part of the toaster holding down the spring loaded tray, so when it is demagnetized, the toast pops up. See Temperature Feedback for more on the bi-metallic strip.

Materials
//What material(s) are essential to the device?//


 * Power Source
 * An **electrical** source is needed to create energy which then can be transformed into heat.
 * Wire [[image:100_1548.jpg width="230" height="171" align="left"]]
 * The wire is usually **nichrome**. This is a mix (alloy) of nickel and chromium. The combination of the two allows the wire to withstand severely high temperatures but not rust or melt, making it quite good for toasters. This nichrome wire is then wrapped back and forth around a mica (metal) sheet.
 * The wire is usually **nichrome**. This is a mix (alloy) of nickel and chromium. The combination of the two allows the wire to withstand severely high temperatures but not rust or melt, making it quite good for toasters. This nichrome wire is then wrapped back and forth around a mica (metal) sheet.
 * The wire is usually **nichrome**. This is a mix (alloy) of nickel and chromium. The combination of the two allows the wire to withstand severely high temperatures but not rust or melt, making it quite good for toasters. This nichrome wire is then wrapped back and forth around a mica (metal) sheet.


 * Metal Sheet
 * The wire is wrapped back and forth around a **mica** **(metal) shee**t. Two of these sheets surround the toast. Mica is used rather than some other material because it resists heat. This causes the heat from the nichrome wire to transfer into the toast rather than the mica sheet. Think for a moment what would happen if the metal sheet inside the toaster were to get very hot. Since the sheet takes up a large space, the entire toaster would get very hot and danger could be present.
 * "Spring-loaded Tray"
 * This is simply a metal tray which "pops-up" when power is lost. The power source(electricity) supplies an electromagnet that holds the tray down. When the power is cut off by a bi-metalic strip (//see above//), the electromagnet loses its magnetism, releasing the tray. When the tray pops up, heat also turns off due to the loss of power. (//See "Controls" -above- for more details)//
 * Timer
 * The timer is another way to cut off the power. Again, when the power is lost, the tray springs up. The timer normally has settings like "light", "medium", and "dark". Depending on how one likes their toast, a different amount of resistance is applied, and/or a different time is set on the timer.

Science
//What scientific principle is central to its operation?//

The toaster uses electricity to heat wires, heating the bread inside. Keep in mind that electricity and heat are both forms of energy. As you can see, its all about energy conversion!

Design
//What does a typical device look like?//

Here's a model of the inside of the toaster. Note the different parts from the above section "Materials" for further explanation.

Evolution
//What changes have there been (or could there be) in this device?//


 * First there was the fire, followed by different types of ovens, leading to the electric oven.
 * Then the original toaster came about in 1909. This toaster only toasted one side of the bread and was turned off manually.
 * Soon an automatic bread flipping toaster was patented.
 * Next came the use of the bi-metallic strip which turned off the toaster at the desired time.
 * Then toasters were able to pop-up bread automatically.
 * Finally came the toaster oven which allows a large variety of food to be toasted.

Competitors
//What other devices serve a similar purpose?//
 * Infrawave Oven
 * Microwave Oven

Partners
//What other devices work in conjunction with this device?//

Kitchen Appliances
 * Blender
 * Dishwasher
 * Freon
 * Ice Dispenser
 * Infrawave Oven
 * Microwave Oven
 * Refrigerator

Siblings
//What other devices use the same scientific principle?//

Using Temperature Feedback Using Nichrome Using Mica
 * Air Conditioner
 * Clothes Dryer
 * Curling Iron
 * Hair Dryer
 * Hair Straightener
 * Infrawave Oven
 * Microwave Oven
 * Refrigerator
 * Explosives
 * Firewords
 * Model Rockets
 * Bridge Wire
 * Ceramics
 * Motercycles
 * Stoves
 * Kerosene Heaters
 * Windows
 * Greenhouses
 * Toothpaste (see Toothbrush (electronic))
 * Automobile Paint
 * Insulators