Pens of one type or another have been used for thousands of years. Today, pens rank among the most widely used writing instruments. More than 2 billion pens are manufactured in the United States annually. There are five main kinds of pens.
They are
(1) ballpoint pens,
(2) fountain pens,
(3) soft-tip pens,
(4) rolling-ball pens, and
(5) specialty pens.
Ballpoint pens:
Ballpoint pens:
They have a tiny ball made of brass, steel, or tungsten carbide as their writing tip. A compartment called the ink reservoir holds the ink, and a narrow tube links the reservoir to the ball. The ball, which is fitted into a socket, turns as it rolls across the paper, carrying ink from inside the pen onto the paper. Many ballpoint pens have a plastic cap that helps prevent ink from drying out on the ball. On others, a push-button mechanism draws the pen point into the body of the pen.
Most ballpoint pens depend on gravity to pull the ink to the ball. For this reason, ballpoint pens generally do not write well when held sideways. However, some ballpoints are designed so that slight pressure is always applied behind the ink column. This design enables the ink to move constantly forward and the pen to write even when its point is higher than its back end. Ballpoint pens use a thick, sticky ink because a thinner ink would leak out around the ball. But the use of such ink makes ballpoint pens write less smoothly than most other pens.
Fountain pens:
Most ballpoint pens depend on gravity to pull the ink to the ball. For this reason, ballpoint pens generally do not write well when held sideways. However, some ballpoints are designed so that slight pressure is always applied behind the ink column. This design enables the ink to move constantly forward and the pen to write even when its point is higher than its back end. Ballpoint pens use a thick, sticky ink because a thinner ink would leak out around the ball. But the use of such ink makes ballpoint pens write less smoothly than most other pens.
Fountain pens:
They have a somewhat triangular writing point, called a nib, which is made of gold or stainless steel. A system of narrow tubes known as the feed carries the ink from the pen’s reservoir to the nib.
Fountain pens use a highly fluid ink. They rely on a property called capillarity to draw the ink into and through the feed. Capillarity causes the inner surface of the tubes to attract molecules of ink. These ink molecules, in turn, attract other ink molecules, and the feed fills with ink from the pen’s reservoir.
The feed in a fountain pen also includes a number of air passages that lead to the reservoir. These passages allow air to fill the top of the reservoir as ink is drawn from the bottom. Thus the air pressure inside the pet remains equal to the air pressure outside the pen, and the ink flows easily. If the air pressure inside the ink reservoir is lower than the atmospheric pressure outside, the ink will not reach the point and the pen will fail to write. However, if the air pressure over the ink column becomes greater than the air pressure outside the pen, ink will flood out from the front of the pen. To avoid such flooding, fountain pens are designed with a collector. The collector, which is located near the nib, consists of a series of fins and spaces that provide enough additional room to accommodate forward moving ink.
Fountain pens use a highly fluid ink. They rely on a property called capillarity to draw the ink into and through the feed. Capillarity causes the inner surface of the tubes to attract molecules of ink. These ink molecules, in turn, attract other ink molecules, and the feed fills with ink from the pen’s reservoir.
The feed in a fountain pen also includes a number of air passages that lead to the reservoir. These passages allow air to fill the top of the reservoir as ink is drawn from the bottom. Thus the air pressure inside the pet remains equal to the air pressure outside the pen, and the ink flows easily. If the air pressure inside the ink reservoir is lower than the atmospheric pressure outside, the ink will not reach the point and the pen will fail to write. However, if the air pressure over the ink column becomes greater than the air pressure outside the pen, ink will flood out from the front of the pen. To avoid such flooding, fountain pens are designed with a collector. The collector, which is located near the nib, consists of a series of fins and spaces that provide enough additional room to accommodate forward moving ink.
Soft-Tip Pens:
Soft-tip pens, also called porous-pointed pens, have a relatively soft writing tip. Some soft-tip pens, called felt-tip pens, have a felt-like writing tip. The tip of others is made of absorbent plastic. Soft-tip pens use fluid, brilliantly colored inks. The reservoir in a soft-tip pen consists of a special synthetic material made up of many fibers. This type of reservoir, called a capillary reservoir, holds ink in much the same way that a sponge holds water. During writing, the absorbent tip of a soft-tip pen continually draws ink from the reservoir onto the paper.
Soft-tip pens, also called porous-pointed pens, have a relatively soft writing tip. Some soft-tip pens, called felt-tip pens, have a felt-like writing tip. The tip of others is made of absorbent plastic. Soft-tip pens use fluid, brilliantly colored inks. The reservoir in a soft-tip pen consists of a special synthetic material made up of many fibers. This type of reservoir, called a capillary reservoir, holds ink in much the same way that a sponge holds water. During writing, the absorbent tip of a soft-tip pen continually draws ink from the reservoir onto the paper.
Roller ball pens :
They combine certain features of ball point, fountain, and soft-tip pens. Like ballpoint pens, roller ball pens have a tiny ball that turns in a socket at their tip. But unlike ballpoints, roller ball pens use highly fluid inks, which allow them to write as smoothly as soft-tip and fountain pens.
Roller ball pens may have either a capillary reservoir similar to that used in soft-tip pens or a reservoir like that of ballpoints. A wick made of an absorbent material draws ink from the reservoir and carries it to the ball. The wick can carry only a limited amount of ink at any onetime. In this way, the wick regulates the flow of ink and prevents it from leaking out.
Specialty pens are designed for specific purposes. for example, artists and mechanical drafters use a pen called a technical pen. This pen comes with a set of interchangeable pen points of varying widths. Another special pen, called a lettering pen, is used to create an elegant style of handwriting called calligraphy.
Roller ball pens may have either a capillary reservoir similar to that used in soft-tip pens or a reservoir like that of ballpoints. A wick made of an absorbent material draws ink from the reservoir and carries it to the ball. The wick can carry only a limited amount of ink at any onetime. In this way, the wick regulates the flow of ink and prevents it from leaking out.
Specialty pens are designed for specific purposes. for example, artists and mechanical drafters use a pen called a technical pen. This pen comes with a set of interchangeable pen points of varying widths. Another special pen, called a lettering pen, is used to create an elegant style of handwriting called calligraphy.
A Note About Pencils :
A Pencil is the most widely used writing and drawing instrument in the world. People use pencils to write words, numbers, music, and poetry, and to draw pictures, plans, maps, and diagrams. There are pencils that write underwater, and pencils used by physicians to mark their patients’ skin before surgery. Astronauts have also taken pencils into space because the writing ability of pencils is unaffected by gravity, pressure, or conditions in the atmosphere. More than 10 billion pencils are produced annually throughout the world. The United States manufactures almost 2 billion pencils yearly—more than any other country.
Pencils consist of a writing core made mostly of graphite set within a case of wood, metal, or plastic. There are three main types of pencils: (1) cased pencils, (2) colored pencils, and 13) mechanical pencils.
Mechanical pencils have a metal or plastic (or wood) case. They use leads similar to those used in cased pencils. Mechanical pencils require no sharpening. The lead is forced out of the pointed end by twisting the cap, or by some other mechanical method. The lead rests inside a spiral (round coil) within the case and is held in place by a rod that has a stud (piece of metal) fastened to it. Whet the cap is twisted, the rod and stud move downward in the spiral, forcing the lead toward the point.
Graphite for pencils is formed into spaghetti like strings, cut to precise measurements, and dried in ovens. Manufacturers vary the proportions of graphite and clay in the mixture to produce pencils with harder and softer writing cores. The Number 2 pencil is the standard and most common pencil used today. Pencils with numbers less than 2 have softer leads and contain less clay and more graphite. Soft pencils make a dark, heavy line. Harder pencils make a finer, lighter line.
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