Can opener

Can opener

Overview
A can opener is a device used to open metal
Metal
A metal , is an element, compound, or alloy that is a good conductor of both electricity and heat. Metals are usually malleable and shiny, that is they reflect most of incident light...

 cans
Tin can
A tin can, tin , steel can, or a can, is a sealed container for the distribution or storage of goods, composed of thin metal. Many cans require opening by cutting the "end" open; others have removable covers. Cans hold diverse contents: foods, beverages, oil, chemicals, etc."Tin" cans are made...

. Although preservation of food
Canning
Canning is a method of preserving food in which the food contents are processed and sealed in an airtight container. Canning provides a typical shelf life ranging from one to five years, although under specific circumstances a freeze-dried canned product, such as canned, dried lentils, can last as...

 using tin cans had been practiced since at least 1772 in the Netherlands, the first can openers were patented only in 1855 in England and in 1858 in the United States. Those openers were basically variations of a knife, and the 1855 design continues to be produced. The first opener employing the now familiar sharp rotating wheel, which runs around the can's rim cutting the lid, was invented in 1870 but was difficult to operate.
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Encyclopedia
A can opener is a device used to open metal
Metal
A metal , is an element, compound, or alloy that is a good conductor of both electricity and heat. Metals are usually malleable and shiny, that is they reflect most of incident light...

 cans
Tin can
A tin can, tin , steel can, or a can, is a sealed container for the distribution or storage of goods, composed of thin metal. Many cans require opening by cutting the "end" open; others have removable covers. Cans hold diverse contents: foods, beverages, oil, chemicals, etc."Tin" cans are made...

. Although preservation of food
Canning
Canning is a method of preserving food in which the food contents are processed and sealed in an airtight container. Canning provides a typical shelf life ranging from one to five years, although under specific circumstances a freeze-dried canned product, such as canned, dried lentils, can last as...

 using tin cans had been practiced since at least 1772 in the Netherlands, the first can openers were patented only in 1855 in England and in 1858 in the United States. Those openers were basically variations of a knife, and the 1855 design continues to be produced. The first opener employing the now familiar sharp rotating wheel, which runs around the can's rim cutting the lid, was invented in 1870 but was difficult to operate. A breakthrough came in 1925 when a second, serrated wheel was added to hold the cutting wheel on the rim of the can. This easy to use design has become one of the most popular can opener models.

Around the time of World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

, several can openers were developed for military use, such as the American P-38
P-38 can opener
The P-38, developed in 1942, is a small can opener issued in the canned field rations of the United States Armed Forces from World War II to the 1980s. Originally designed for and distributed in the K-ration, it was later included in the C-ration.- Design :...

 and P-51. These featured a robust and simple design where a folding knife and absence of a handle significantly reduced the opener size. Electric can openers were introduced in the late 1950s and met with success. The development of new can opener types continues with the recent addition of a side-cutting model.

Invention of cans


Food preserved in tin cans was in use by the Dutch Navy from at least 1772. Before 1800, there was already a small industry of canned salmon
Salmon
Salmon is the common name for several species of fish in the family Salmonidae. Several other fish in the same family are called trout; the difference is often said to be that salmon migrate and trout are resident, but this distinction does not strictly hold true...

 in the Netherlands. Freshly caught salmon were cleaned, boiled in brine
Brine
Brine is water, saturated or nearly saturated with salt .Brine is used to preserve vegetables, fruit, fish, and meat, in a process known as brining . Brine is also commonly used to age Halloumi and Feta cheeses, or for pickling foodstuffs, as a means of preserving them...

, smoked and placed in tin-plated iron boxes. This canned salmon was known outside the Netherlands, and in 1797 a British company supplied one of their clients with 13 cans. Preservation of food in tin cans was patented by Peter Durand
Peter Durand
Peter Durand was a British merchant who is widely credited with receiving the first patent for the idea of preserving food using tin cans. The patent was granted on August 25, 1810 by King George III of England....

 in 1810. The patent was acquired in 1812 by Bryan Donkin
Bryan Donkin
Bryan Donkin was an English engineer and industrialist. Of his six sons, John, Bryan, and Thomas also became engineers.-Early life:Born in Sandoe, Northumberland, his father was a surveyor and land agent...

 who had later set up the world’s first canning factory in London in 1813. By 1820, canned food was a recognized article in Britain and France and by 1822 in the United States. The first cans were robust containers, which weighed more than the food they contained and required ingenuity to open, using whatever tools available. The instruction on those cans read "Cut round the top near the outer edge with a chisel and hammer."

First, lever-type can openers


Dedicated can openers appeared in the 1850s and were of a primitive claw-shaped or "lever-type" design. In 1855, Robert Yeates, a cutlery and surgical instrument maker of Trafalgar Place West, Hackney Road, Middlesex
Middlesex
Middlesex is one of the historic counties of England and the second smallest by area. The low-lying county contained the wealthy and politically independent City of London on its southern boundary and was dominated by it from a very early time...

, UK, devised the first claw-ended can opener with a hand-operated tool that haggled its way around the top of metal cans.

In 1858, another lever-type opener of a more complex shape was patented in the US by Ezra Warner
Ezra Warner
Ezra J. Warner of Waterbury, Connecticut was an American inventor, who patented his design of a can opener in 1858. Crudely shaped bayonet and sickle combo, his design was widely accepted by the U.S...

 of Waterbury, Connecticut
Waterbury, Connecticut
Waterbury is a city in New Haven County, Connecticut, on the Naugatuck River, 33 miles southwest of Hartford and 77 miles northeast of New York City...

. It consisted of a sharp sickle, which was pushed into the can and sawed around its edge. A guard kept the sickle from penetrating too far into the can. The opener consisted of several parts which could be replaced if worn out, especially the sickle. This opener was adopted by the US Army during the American Civil War
American Civil War
The American Civil War was a civil war fought in the United States of America. In response to the election of Abraham Lincoln as President of the United States, 11 southern slave states declared their secession from the United States and formed the Confederate States of America ; the other 25...

 (1861–1865); however, its unprotected knife-like sickle was too dangerous for domestic use. A home-use opener named the "Bull's head opener" was designed in 1865 and was supplied with cans of pickled beef named "Bully beef". The opener was made of cast iron and had a very similar construction to the Yeates opener, but featured a more artistic shape and was the first move towards improving the look of the can opener. The bull-headed design was produced until the 1930s and was also offered with a fish-head shape.

Rotating wheel openers


The first rotating wheel can opener was patented in July 1870 by William Lyman
William Lyman (inventor)
William Worcester Lyman was an American inventor from Meriden, Connecticut. He is credited with inventing the first rotating wheel can opener.William Lyman was born in 1821 in Middlefield, Connecticut...

 of Meriden, Connecticut
Meriden, Connecticut
Meriden is a city in New Haven County, Connecticut, United States. According to 2005 Census Bureau estimates, the population of the city is 59,653.-History:...

, US and produced by the firm Baumgarten in the 1890s. The can was to be pierced in its center with the sharp metal rod of the opener. Then the length of the lever had to be adjusted to fit the can size, and the lever fixed with the wingnut. The top of the can was cut by pressing the cutting wheel into the can near the edge and rotating it along the can's rim.

The necessity to pierce the can first was a nuisance, and this can opener design has not survived till present days. In 1925, the Star Can Opener Company of San Francisco, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

 had improved the Lyman's design by adding a second, toothed wheel called "feed wheel", which allowed a firm grip of the can edge. This addition was so efficient that the design is still in use today.

Whereas all previous openers required using one hand, or other means, to hold the can, can-holding openers both hold the can and open it. The first such opener was patented in 1931 by the Bunker Clancey Company of Kansas City, Missouri and was therefore called the "Bunker". It featured the now standard pliers-type handle, grasping which would tightly hold the can, while turning the key would rotate the cutting wheel progressively cutting the lid along the rim. The Bunker company was absorbed by the Rival Manufacturing Company, also of Kansas City, in 1938.

Churchkey


Churchkey initially referred to a simple hand-operated device for prying the cap (called a "crown cork
Crown Cork
The crown cork , the first form of bottle cap, was invented by William Painter in 1891 in Baltimore. The company making it was originally called the Bottle Seal Company, but it changed its name with the almost immediate success of the crown cork to the Crown Cork and Seal Company...

") off a glass bottle; this kind of closure was invented in 1892. The first of these churchkey style openers was patented in Canada in 1900. The shape and design of some of these openers did resemble a large simple key. In 1935, beer cans with flat tops were marketed, and a device to puncture the lids was needed. The same churchkey opener was used for piercing those cans. It was made from a single piece of pressed metal, with a pointed end used for piercing cans—devised by D.F. Sampson, for the American Can Company
American Can Company
The American Can Company was a manufacturer of tin cans. It was a member of the Tin Can Trust, that controlled a "large percentage of business in the United States in tin cans, containers, and packages of tin." It was formerly a member of the Dow Jones Industrial Average from 1959–1991, though...

, who depicted operating instructions on the cans themselves, The churchkey opener is still being produced, usually as an attachment to another opener. For example, a "butterfly" opener is often a combination of the churchkey and a serrated-wheel opener.

There is sparse, and often contradictory, documentation as to the origin of the term "churchkey". The phrase is likely a sarcastic
Sarcasm
Sarcasm is “a sharp, bitter, or cutting expression or remark; a bitter jibe or taunt.” Though irony and understatement is usually the immediate context, most authorities distinguish sarcasm from irony; however, others argue that sarcasm may or often does involve irony or employs...

 euphemism
Euphemism
A euphemism is the substitution of a mild, inoffensive, relatively uncontroversial phrase for another more frank expression that might offend or otherwise suggest something unpleasant to the audience...

, as the opener was obviously not designed to access churches. One explanation is in Medieval Europe, most brewers were monks. Lagering cellars in the monasteries were locked, to protect aging beers and the monks carried keys to these lagering cellars. It may have been those keys, which remotely resembled the early churchkey openers, that gave the "churchkey" opener its name. Another motive for assigning the device such an ironic name could have been the fact beer was first canned (for test marketing) in 1933—the same year Franklin Delano Roosevelt signed the Cullen-Harrison Bill. This act, which predated Repeal of Prohibition
Repeal of Prohibition
The Repeal of Prohibition in the United States was accomplished with the passage of the Twenty-first Amendment to the United States Constitution on December 5, 1933.-Background:...

, amended the Volstead Act
Volstead Act
The National Prohibition Act, known informally as the Volstead Act, was the enabling legislation for the Eighteenth Amendment which established prohibition in the United States...

, making 3.2 beer legal. Some experts have posited the term "churchkey" was a way to "stick it to" the religious organizations who had effected Prohibition
Prohibition
Prohibition of alcohol, often referred to simply as prohibition, is the practice of prohibiting the manufacture, transportation, import, export, sale, and consumption of alcohol and alcoholic beverages. The term can also apply to the periods in the histories of the countries during which the...

 in the first place.

Another key opener with completely different design was patented by J. Osterhoudt in 1866. Instead of piercing the can it was used to roll a stripe off the can. It was also called "key", because of resemblance to a door key. Such openers are attached to many small, thin-walled cans nowadays.

Military use can openers


Several can openers with a simple and robust design had been specifically developed for military use. The P-38 and P-51 are small can openers with a cutter hinged to the main body. They were also known as "John Wayne
John Wayne
Marion Mitchell Morrison , better known by his stage name John Wayne, was an American film actor, director and producer. He epitomized rugged masculinity and became an enduring American icon. He is famous for his distinctive calm voice, walk, and height...

" because the actor was shown in a training film opening a can of K-rations. The P-38 can opener is keychain
Keychain
A keychain or key chain is a small chain, usually made from metal or plastic, that connects a small item to a keyring. The length of a keychain allows an item to be used more easily than if connected directly to a keyring...

-sized (about 1.5 inches, 38mm, in length) and consists of a short metal blade
Blade
A blade is that portion of a tool, weapon, or machine with a cutting edge and/or a pointed tip that is designed to cut and/or puncture, stab, slash, chop, slice, thrust, or scrape animate or inanimate surfaces or materials...

 that serves as a handle (and can also be used as a screwdriver
Screwdriver
A screwdriver is a tool for driving screws and often rotating other machine elements with the mating drive system. The screwdriver is made up of a head or tip, which engages with a screw, a mechanism to apply torque by rotating the tip, and some way to position and support the screwdriver...

), with a small, hinged metal tooth that folds out to pierce the can lid. A notch just under the hinge point keeps the opener hooked around the rim of the can as the device is "walked" around to cut the lid out. A larger version called P-51 is somewhat easier to operate. P-38 was developed in 1942 and was issued in the canned field rations of the United States Armed Forces
United States armed forces
The United States Armed Forces are the military forces of the United States. They consist of the Army, Navy, Marine Corps, Air Force, and Coast Guard.The United States has a strong tradition of civilian control of the military...

 from World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

 to the 1980s. The P-38 and P-51 are cheaper to manufacture and are smaller and lighter to carry than most other can openers. The device can be easily attached to a keyring or dog tag
Dog tag (identifier)
A dog tag is the informal name for the identification tags worn by military personnel, named such as it bears resemblance to actual dog tags. The tag is primarily used for the identification of dead and wounded and essential basic medical information for the treatment of the latter, such as blood...

 chain using the small punched hole.

Official military designations for the P-38 include 'US Army pocket can opener' and 'Opener, can, hand, folding, type I'. As with some other military terms (e.g. jeep
Jeep
Jeep is an automobile marque of Chrysler . The first Willys Jeeps were produced in 1941 with the first civilian models in 1945, making it the oldest off-road vehicle and sport utility vehicle brand. It inspired a number of other light utility vehicles, such as the Land Rover which is the second...

), the origin of the term is not known with certainty. The P-38 and P-51 openers share a designation with the P-38 and P-51 fighter planes, however this is coincidental. The most likely origin of the name is much more pedestrian; the P-38 is 38 mm (1.5 in) long. This explanation also holds for the P-51, which measures 51 mm (2 in) in length.

P-38s are no longer used for individual rations by the United States Armed Forces, as canned C-rations were replaced by uncanned MREs in the 1980s. They are, however, included with US military "Tray Rations" (canned bulk meals). They are also still seen in disaster recovery efforts and have been handed out alongside canned food by rescue organizations, both in America and abroad in Afghanistan. The original US-contract P-38 can openers were manufactured by J.W. Speaker Corp. (stamped "US Speaker") and by Washburn Corp. (marked "US Androck"), they were later made by Mallin Hardware (now defunct) of Shelby, Ohio
Shelby, Ohio
Shelby is a city in Richland County in the U.S. state of Ohio, northwest of the city of Mansfield. It is part of the Mansfield, Ohio Metropolitan Statistical Area. The population was 9,821 at the 2000 census.-History:...

 and were variously stamped "US Mallin Shelby O." or "U.S. Shelby Co.".
A similar device that incorporates a small spoon at one end and a bottle opener at the other is currently employed by the Australian Defence Force
Australian Defence Force
The Australian Defence Force is the military organisation responsible for the defence of Australia. It consists of the Royal Australian Navy , Australian Army, Royal Australian Air Force and a number of 'tri-service' units...

 and New Zealand Army
New Zealand Army
The New Zealand Army , is the land component of the New Zealand Defence Force and comprises around 4,500 Regular Force personnel, 2,000 Territorial Force personnel and 500 civilians. Formerly the New Zealand Military Forces, the current name was adopted around 1946...

 in its ration kits. The Field Ration Eating Device
Field Ration Eating Device
The Field Ration Eating Device is a small device which is a combination of a can opener, a bottle opener and a spoon. It is issued to the Australian Defence Force in its CR1M ration packs. It is also known widely by its derogative term, the "Fucking Ridiculous Eating Device".The can opener is very...

 is known by the acronym "FRED". It is also known widely in its derogative term, the "Fucking Ridiculous Eating Device".

Another similar device was included with British Army 'Operational Ration Pack, General Purpose' 24-hour ration pack and 'Composite Ration Pack' rations. At one stage they were manufactured by W.P. Warren Engineering Co. Ltd. The instructions printed on the miniature greaseproof paper bag they were supplied in read: "Their design is similar, but not identical, to the P-38 and P-51 can openers."

Most military use can openers have a very simple design and have also been produced for civilian use in many countries. For example, small folding openers similar to the P-38 and P-51 were designed back in 1924 and have been widely distributed in the Eastern Europe
Eastern Europe
Eastern Europe is the eastern part of Europe. The term has widely disparate geopolitical, geographical, cultural and socioeconomic readings, which makes it highly context-dependent and even volatile, and there are "almost as many definitions of Eastern Europe as there are scholars of the region"...

an countries.

In Slovenia
Slovenia
Slovenia , officially the Republic of Slovenia , is a country in Central and Southeastern Europe touching the Alps and bordering the Mediterranean. Slovenia borders Italy to the west, Croatia to the south and east, Hungary to the northeast, and Austria to the north, and also has a small portion of...

 a somewhat rounded version of a P-38 is known as "sardine
Sardine
Sardines, or pilchards, are several types of small, oily fish related to herrings, family Clupeidae. Sardines are named after the Mediterranean island of Sardinia, around which they were once abundant....

 can opener
" because it was (in the nineties) usually packed with cans that did not feature the pull-and-tear precut top.

Electric openers



The first electric can opener was patented in 1931 and modeled after the cutting-wheel design. Those openers have been produced in 1930s and advertised as capable to remove lids from more than 20 cans per minute without any risk of injury. Nevertheless, they found little success. Electric openers were re-introduced in 1956 by two Californian companies. Klassen Enterprises of Centreville brought out a wall-mounted electric model, but this complex design was unpopular too.

The same year, Walter Hess Bodle invented a freestanding device combining an electric can opener and knife sharpener. He and his family members built their prototype in his garage with daughter Elizabeth sculpting the body design. It was manufactured under the "Udico" brand of the Union Die Casting Co. in Los Angeles
Los Ángeles
Los Ángeles is the capital of the province of Biobío, in the commune of the same name, in Region VIII , in the center-south of Chile. It is located between the Laja and Biobío rivers. The population is 123,445 inhabitants...

and came in the flamingo pink, avocado green, and aqua blue colors of the era. These openers were introduced on the market for Christmas sales and had immediate success.

Modern designs



A new style of can opener emerged in 1980s. Whereas most other openers cut the can from the top, this one cuts the can from the side, very near its top. The rim is neatly cut in half in the plane of the flat end, leaving half of the rim attached to the can and the other half attached to the flat end. No sharp edges are produced on the lid. The driving teeth are a lot finer than those of the classical can opener and reside at the bottom of a V-shaped groove, which surrounds the rim on three sides at the point of action.