Many of these have a one-way locking mechanism to allow the lead to be pushed back into the pencil.Ī clutch pencil (or leadholder) tends to use thicker leads (2.0–5.6 mm) and generally holds only one piece of lead at a time. This was the most common type in the earlier part of the twentieth century. Screw-based pencils advance the lead by twisting a screw, which moves a slider down the barrel of the pencil. Mechanical pencils can be divided into two basic types: those that both hold the lead and can actively propel it forward, and those that only hold the lead in position. Rotring 600 metal body with matte coating A Pentel GraphGear 1000 featuring a clip-operated retractable lead guide pipe and lead hardness grade indicator set at HB. A Staedtler 925-25 05 assembled (top) and disassembled (bottom). Mechanism types A Pentel Sharp ratchet drafting pencil disassembled, showing three 0.5 mm graphite leads. Some of the manufacturers are: Pentel, Pilot, Tombow, Uni-ball and Zebra of Japan Faber-Castell, Lamy, Rotring and Staedtler of Germany Koh-i-Noor Hardtmuth of the Czech Republic Bic of France Monami of South Korea PaperMate and Parker of USA Caran d'Ache of Switzerland and numerous Chinese as well as other Asian and European manufacturers. After some improvements, his design was marketed as the " Eversharp" pencil by the Wahl Adding Machine Company by the early 1920s, Wahl had sold more than 12,000,000 Eversharps. Keeran patented his lead pencil in 1915 and soon afterwards arranged production. These two development histories – Hayakawa and Keeran – are often mistakenly combined into one. Keeran's design was ratchet-based, whereas Hayakawa's was screw-based. Keeran was developing a similar pencil that would be the precursor of most of today's pencils. Īt nearly the same time in the US, Charles R. Later, Tokuji Hayakawa's company got its name from that pencil: Sharp. The Ever-Ready Sharp began selling in huge numbers after a company from Tokyo and Osaka made large orders. Success was not immediate since the metal shaft-essential for the pencil's long life-was unfamiliar to users. It was introduced as the "Ever-Ready Sharp Pencil". The mechanical pencil became successful in Japan with some improvements in 1915 by Tokuji Hayakawa, a metalworker who had just finished his apprenticeship. Eventually, 1.3 and 1.4 mm mechanisms were available, and 0.4 and 0.2 versions are now produced. The 0.9 mm lead was introduced in 1938, and later it was followed by 0.3, 0.5 and 0.7 sizes. The first spring-loaded mechanical pencil was patented in 1877 and a twist-feed mechanism was developed in 1895. His company continued to manufacture pencils and a wide range of silver objects until World War II, when the factory was bombed.īetween 18, more than 160 patents were registered pertaining to a variety of improvements to mechanical pencils. After 1837, Mordan ended his partnership with Riddle and continued to manufacture pencils as "S. The earliest Mordan pencils are thus hallmarked SMGR. After buying out Hawkins' patent rights, Mordan entered into a business partnership with Gabriel Riddle from 1823 to 1837. The first patent for a refillable pencil with lead-propelling mechanism was issued to Sampson Mordan and John Isaac Hawkins in Britain in 1822. The earliest extant example of a mechanical pencil was found aboard the wreckage of HMS Pandora, which sank in 1791. History Detail of the first patent for a mechanical pencil of Sampson Mordan, 1822Ĭonrad Gesner described a lead holder pencil in 1565, but the lead had to be manually adjusted to sharpen it. Mechanical pencils were first used in the 18th century, with many designs patented in the 19th and 20th centuries. Since they do not have to be sharpened, they are also popular with students. Mechanical pencils are used to provide lines of constant width, without need of sharpening, for tasks such as technical drawing as well as for clean looking writing. the 1980s), propelling pencil (British and Australian English, often refers to higher-end mechanical pencils), pen pencil (Indian English), and lead pencil (Bangladeshi and American English). Other names include: microtip pencil, automatic pencil, drafting pencil, technical pencil, draughting pencil, click pencil (generally refers to a specific brand), pump pencil, leadholder, Pacer (Australian English, ca. The vast majority of mechanical pencils have erasers. The lead, often made of graphite, is not bonded to the outer casing, and can be mechanically extended as its point is worn away as it is being used. Pencil with a replaceable and mechanically extendable solid pigment coreĪ typical construction of a ratchet-based mechanical pencilĪ mechanical pencil, also clutch pencil, is a pencil with a replaceable and mechanically extendable solid pigment core called a "lead" / ˈ l ɛ d/.
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