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 A ratchet-type mechanical pencil A mechanical pencil, lead pencil or clicky pencil (other names include clutch pencil, or Pacer after a Papermate model, a genericized trademark) is a pencil containing an internal mechanism which pushes ("propels") the thin graphite lead through the tip. Like standard pencils, there are also mechanical pencils which have a rubber eraser on the end. Mechanical pencils provide lines of consistent thickness, well suited for technical applications such as drafting and writing. Image File history File links Question_book-3. ...
Wikipedia does not have an article with this exact name. ...
Papermate, a division of Newell Rubbermaid is a company that makes stationery. ...
A genericized trademark, generic trade mark, generic descriptor, or proprietary eponym, is a trademark or brand name which has become the colloquial or generic description for a particular class of product or service. ...
This article is about the handwriting instrument. ...
For other uses, see Graphite (disambiguation). ...
This does not cite any references or sources. ...
For other uses, see Eraser (disambiguation). ...
History
The mechanical pencil was first invented in Britain in 1822 by Sampson Mordan [1] and Gabriel Riddle. Earliest Mordan pencils are thus hallmarked SMGR. Sampson Mordan continued manufacturing pencils and a wide range of silver objects until the second world war when their factory was bombed.
Between 1820 and 1873, more than 160 patents were registered pertaining to a variety of improvements to mechanical pencils. The first spring-loaded mechanical pencil was patented in 1877 and a twist-feed mechanism was developed in 1895. The 0.9mm lead was introduced in 1938, and later it was followed by 0.7mm, 0.5mm and 0.3mm versions. Even the 1.4mm version is available. For other uses, see Spring. ...
The mechanical pencil became successful in Japan with some improvements in 1915 by Tokuji Hayakawa, a metal worker who had just finished his apprenticeship. It was introduced as the Ever-Ready Sharp Pencil. Success was not immediate, since the metal shaft — essential for the pencil's long life — was unfamiliar to users. The Ever-Sharp began selling in huge numbers, however, after a company from Yokohama made a large order. Later Tokuji Hayakawa's company got its name from that pencil: Sharp. For the town of Yokohama in Aomori Prefecture, see Yokohama, Aomori. ...
Sharp Corporation ) (TYO: 6753 , LuxSE: SRP) is a Japanese electronics manufacturer, founded in 1912. ...
At nearly the same time, in America, Charles R. Keeran was developing a similar pencil that would be the precursor of most of today's pencils. Keeran's design was ratchet-based, whereas Hayakawa's was screw-based. These two development histories are often combined into one.
Types
 A rachet mechanical pencil disassembled, showing three 0.5mm graphite leads. A number of different types exist: Wikipedia does not have an article with this exact name. ...
Wikipedia does not have an article with this exact name. ...
Image File history File linksMetadata Download high-resolution version (1300x763, 434 KB) Pentel 0. ...
Image File history File linksMetadata Download high-resolution version (1300x763, 434 KB) Pentel 0. ...
- Ratchet-based pencils, in which the lead is advanced by a button on either the end or the side. This button pushes two or three small pieces within the cap forward out of a ring holding them together as one. This separates those pieces, allowing lead to go through between those.
- A variation of the ratchet-based pencil, which by shaking the pencil back and forth, a weight inside the pencil operates the mechanism in the cap. A button may or may not be present depending on design.
- Another variation advances the lead automatically. In this design, the lead is advanced by a ratchet but only prevented from going back into the pencil, just held from falling by a small amount of friction. The nib is a spring-loaded collar that, when depressed as the lead is worn away, pulls out more when pressure is next released.
- Screw-based pencils, in which the lead is advanced by twisting a screw, which moves a slider down the barrel of the pencil.
- Screw-based pencils in which the lead is advanced by friction with the screw.
- Twist-based pencils, in which the lead advances upon twisting the head of the pencil. Many of these will have a locking mechanism one way to allow the lead to be pushed back into the pencil.
Most mechanical pencils can be refilled with more graphite but some less-expensive models, especially screw-based designs, are disposable. A ratchet lever hoist. ...
For other uses, see Friction (disambiguation). ...
Screws come in a variety of shapes and sizes for different purposes. ...
Clutch pencil
 A STAEDTLER Mars 780 Leadholder Clutch pencils (or leadholders) use a thicker solid piece of lead (typically 2mm to 4 mm) and work by pressing down the eraser cap to allow the "claws" at the end to open, which in turn allows the lead to freely drop through the barrel. They can typically only hold one whole piece of lead at a time. Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (2048 × 1536 pixel, file size: 1. ...
Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (2048 × 1536 pixel, file size: 1. ...
Image File history File linksMetadata Size of this preview: 800 × 533 pixelsFull resolution (4368 × 2912 pixel, file size: 2. ...
Image File history File linksMetadata Size of this preview: 800 × 533 pixelsFull resolution (4368 × 2912 pixel, file size: 2. ...
The advantage of clutch pencils is that they allow a greater variety of marks to be made.
The disadvantage is that because the lead falls when the claws are opened, there is no controlled dispersal of the lead and as such it's best done a few millimeters over the work surface.
Manufacturers Bic Corporation is a company based in Clichy, France, founded in 1945, best known for making inexpensive disposable products including cigarette lighters, magnets, ballpoint pens, and shaving razors. ...
Faber-Castell logo Faber-Castell erasers Faber-Castell is a German manufacturer of writing instruments, art supplies and slide rules, founded in 1761 in Nuremberg by Kaspar Faber. ...
Koh-I-Noor Hardtmuth a. ...
Lamy (IPA: lɑmɪ ) is the leading producer of fountain pens in Europe. ...
Papermate, a division of Newell Rubbermaid is a company that makes stationery. ...
The headquarters of Pentel, in Tokyo. ...
Rotring is a German company based in Hamburg. ...
Staedtler is one of the worlds leading manufacturers and suppliers of writing and engineering drawing instruments and is the maker of the Mars Pencil and Mars Eraser. ...
Zebra Pen Corporation is an American manufacturer of writing instruments. ...
Pilot Pen Corporation is a pen manufacturer based in Tokyo, Japan. ...
References is the 93rd day of the year (94th in leap years) in the Gregorian calendar. ...
Year 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era in the 21st century. ...
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