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- "HOME TECH": The Inner Workings NewScience
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- The Toilet
-
- Yes...those tales you've heard are true. The toilet was first
- patented in England in 1775, invented by one Thomas Crapper,
- but the extraordinary automatic device called the flush toilet
- has been around for a long time. Leonardo Da Vinci in the
- 1400's designed one that worked, at least on paper, and Queen
- Elizabeth I reputably had one in her palace in Richmond in
- 1556, complete with flushing and overflow pipes, a bowl valve
- and a drain trap. In all versions, ancient and modern, the
- working principle is the same.
-
- Tripping a single lever (the handle) sets in motion a series
- of actions. The trip handle lifts the seal, usually a rubber
- flapper, allowing water to flow into the bowl. When the tank
- is nearly empty, the flap falls back in place over the water
- outlet. A floating ball falls with the water level, opening
- the water supply inlet valve just as the outlet is being
- closed. Water flows through the bowl refill tube into the
- overflow pipe to replenish the trap sealing water. As the
- water level in the tank nears the top of the overflow pipe,
- the float closes the inlet valve, completing the cycle.
-
- From the oldest of gadgets in the bathroom, let's turn to
- one of the newest, the toothpaste pump. Sick and tired of
- toothpaste squeezed all over your sink and faucets? Does
- your spouse never ever roll down the tube and continually
- squeezes it in the middle? Then the toothpaste pump is
- for you!
-
- When you press the button it pushes an internal, grooved
- rod down the tube. Near the bottom of the rod is a piston,
- supported by little metal flanges called "dogs", which seat
- themselves in the grooves on the rod. As the rod moves down,
- the dogs slide out of the groove they're in and click into
- the one above it. When you release the button, the spring
- brings the rod back up carrying the piston with it, now
- seated one notch higher. This pushes one-notch's-worth of
- toothpaste out of the nozzle. A measured amount of toothpaste
- every time and no more goo on the sink.
-
- Refrigerators
-
- Over 90 percent of all North American homes with electricity
- have refrigerators. It seems to be the one appliance that
- North Americans can just not do without. The machine's
- popularity as a food preserver is a relatively recent
- phenomenon, considering that the principles were known as
- early as 1748. A liquid absorbs heat from its surroundings
- when it evaporates into a gas; a gas releases heat when it
- condenses into a liquid.
-
- The heart of a refrigerator cooling system is the compressor,
- which squeezes refrigerant gas (usually freon) and pumps it
- to the condenser, where it becomes a liquid, giving up heat
- in the process. The condenser fan helps cool it. The
- refrigerant is then forced through a thin tube, or capillary
- tube, and as it escapes this restraint and is sucked back
- into a gas again, absorbing some heat from the food storage
- compartment while it does so. The evaporator fan distributes
- the chilled air.
-
- In a self-defrosting refrigerator/freezer model, moisture
- condenses into frost on the cold evaporator coils. The
- frost melts and drains away when the coils are warmed
- during the defrost cycle which is initiated by a timer, and
- ended by the defrost limiter, before the frozen food melts.
- A small heater prevents condensation between the compartments,
- the freezer thermostat turns the compressor on and off, and
- the temp control limits cold air entering the fridge, by
- means of an adjustable baffle.
-
- Smoke Detectors
-
- Is your smoke detector good at scaring to death spiders who
- carelessly tiptoe inside it? Have you ever leapt out of the
- shower, clad only in you-know-what, to the piercing tones of
- your alarm, triggered merely by your forgetting the close the
- bathroom door? Is it supposed to do this?
-
- There are two types of smoke detectors on the market; the
- photoelectric smoke detector and ionization chamber smoke
- detector. The photoelectric type uses a photoelectric bulb
- that shines a beam of light through a plastic maze, called a
- catacomb. The light is deflected to the other end of the
- maze where it hits a photoelectric cell. Any smoke impinging
- on this light triggers the alarm (as do spiders and water
- droplets in the air!). The ionization chamber type contains
- a small radiation source, usually a man-made element called
- Americium. The element produces electrically-charged air
- molecules called ions, and their presence allows a small
- electric current to flow in the chamber. When smoke
- particles enter the chamber they attach themselves to these
- ions, reducing the flow of current and triggering the alarm.
-
- Both types are considered equally effective and may be
- battery-powered or wired to the home's electrical system.
- No matter which type you choose, if you don't have one
- installed, put down this article and go buy one now!
-
- And while you're signing that credit card voucher for the
- new smoke detector, pause for a moment and gaze at that
- other technological marvel you are probably holding in your
- hand, the ball-point pen. Ever wonder why it's called a
- ball-point? Because it has a ball. The first European
- patents for the handy device were issued in the late 19th
- century, but none of the early pens worked very well until
- a Swiss inventor named Lazio Josef Biro designed the first
- modern version in 1939. He called it a birome.
- Commercial production was delayed by World War II, and
- then in 1945, an American firm, Reynold's, introduced "the
- miraculous pen which revolutionizes writing" at Gimbel's in
- New York City. The new pen didn't work very well and cost a
- whopping $12.50 U.S., but it was an instant success. The
- Henry Ford of the ball-point industry, Marcel Bich, launched
- the Bic pen in 1949, after developing the Biro design for two
- years to produce a precision instrument which wrote evenly
- and reliably and was cheap. By the early seventies, Bic pens
- became the world's largest manufacturer of ball-point pens,
- and today some two and one-half million Bic ball-points alone
- are sold every day in North America.
-
- Ink feeds by gravity through five veins in a nose cone,
- usually made of brass, to a tungsten carbide ball. During the
- writing process, the ball rotates, picking up a continuous
- ink supply through the nose cone and transferring it to the
- writing paper. The ball is a perfect sphere, which must fit
- precisely into the extremely smooth nose cone socket so that
- it will rotate freely yet be held tightly in place so that
- there is an even ink flow. Although it sounds deceptively
- simple, perhaps the most amazing thing about ball-point pens
- is the ink. Why doesn't it just run out the end? Why doesn't
- it dry up in the plastic cartridge? Bic describes the ink as
- "exclusive, fast-drying, yet free flowing". The formula is,
- of course, secret.
-
- In the 19th century, writer and thinker Ralph Waldo Emerson
- expressed a fear that perhaps we all feel to some extent, that
- "things are in the saddle and ride Mankind". But with the help
- of good household reference books, friendly reference
- librarians, and helpful manufacturers only too willing to help
- consumers understand their products, we can at least get a
- rein on the technology in our homes.
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