Clothes+Dryer

=Clothes Dryer= Cdo, Dgambone

//What is the fundamental purpose of the device?//
Clothes dryers are used to dry clothes in a very simple way that doesn't require much work. They allow people to have control of the way they want their laundry to be dried. Dryers are a common household appliance in homes across the United States.

Energy
//What energy transformations are seen in its operation?// When the air enters the body of the dryer, it is kinetic energy. The heating element that the air passes through uses electrical energy. Heating elements can use up to 6,000 watts. Electric energy is used when the fan spins the air and forces it out the exhaust duct in the back of the dryer. An electric motor is also used to drive the pulleys that make the tumbler spin.

Controls
//What sensors/controls are designed into the device?// Click this link to see a diagram of the cycle switch:
 * Cycle Switch:** This switch controls the type of cycle and the amount of time the cycle runs. On the back of the switch, is a tiny motor. When you turn the switch, the motor turns the gear on the dial. The dial is attached to four cams//(disk),// that are stacked on top of each other. There are also four contacts in the switch box. Each contact is located at a different height in the box. The bottom left contact is the lowest, and moving counterclockwise, the contacts get higher. The four cams match with one of the contacts at different heights. The cycle switch also controls at what time the heating elements are on. If none of the heating elements are on, then only cool air comes through the dryer. If one heating element is on, then the air is warm. If both are on, then the air is hot.
 * Temperature Shut-Off Switch:** There are two small silver discs that ensure the dryer isn't getting too hot. One is located at the front of the dryer, and the other is located near the heating element. These discs have contacts within them and when they get too hot, the contacts break. When the contacts break, the entire dryer is shut off.

Materials
//What material(s) are essential to the device?// The duct that allows air to enter and leave the dryer machine is very essential because without it, there would be no air to dry the clothes. A duct can be made out of 4 different types of materials. The preferred type of ducting material is Rigid Metal (aluminum or galvanized steel.) An acceptable type of ducting material is Flexible metal. The two types of unacceptable ducting material are Flexible Thin Foil and Flexible Plastic. They can cause unwanted dryer fires, lint build-up, or improper venting. Lint screens are needed to stop the build-up of lint, which is the fibers and particles on clothing. Other materials that make a dryer function correctly are the door, motors, which are usually run by either gas or electric, the tumbler belt, which is the belt that turns the barrel that circulates the clothes inside of the dryer, etc.

Science
//What is scientific principle is central to its operation?// The most important thing to a clothes dryer is the way the dryer heats up the air. This can be done in two different ways; electric or gas. When using electricity, there is usually a coiled wire that heats up by an electric current. These washing machines can be plugged into an outlet, and that is where they get the electricity from. Most electric dryers use up to 240 volts. Gas dryers work almost the same way, except the heat comes from the gas burner. Houses must have good venting to get rid of the gas exhaust. The gas burners burn natural gas, propane, or butane.

Design
//What does a typical device look like?// A typical clothes dryer usually has a hinged door this is typically located in the front outer face. The controls and switches are also normally at the top for easy reach. Clothes dryers come in various colors and shapes (based on the manufacturer). Clothes dryers are usually made of strong metal. Click these links that will take you to different pictures of clothes dryers: http://z.hubpages.com/u/190902_f520.jpg http://www.lge.com/us/appliances/images/lg-Dryers-DLEX7177RM-3_4view-01-large.png

Evolution
//What changes have there been (or could there be) in this device?// Clothes dryers have come along way since when they were first invented. They have come up with different types of dryers that can do different tasks better than others. For example, a spin dryer spins its drums faster so the water is drawn out of the clothes faster, which saves time and energy. Condensation dryers use a heat exchanger that cools the air and condenses the water vapor into a drain pipe and the air is ran through the dryer again. Heat pump dryers do the same thing as condensation dryers, except it uses a heat pump instead of a heat exchanger. These dryers saves heat and therefore uses less energy than traditional tumble dryers and condensation dryers. A mechanical steam compression dryer is the more advanced version of the heat pump dryer. It uses the water from the clothing in the form of steam, to dry the clothes. When this steam exits the dryer, it is compressed, heated and then reenters the tumbler. This dryer is also very energy-efficient. There have been many small changes to the designs of clothes dryer machines, such as the shape of the doors, buttons, and the color of the machine.

Competitors
//What other devices serve a similar purpose?//
 * No other devices use a similar purpose

Partners
//What other devices work in conjunction with this device?//
 * //Washing machine//
 * //Dishwasher//

Siblings
//What other devices use the same scientific principle?//
 * //Dishwasher//
 * //Hair Dryer//

To find out more devices that use the same scientific principle click these links: Electric Current Electricity to Heat