Technical Description

CAN OPENER
How it works? How it’s made?
Cristian Alexander Diaz Salazar
ENG-202: Technical Writing
Prof: Pamela Stemberg
September, 28 2022

Outline

I. Introduction………………………………………………………………………….3
II. How it’s made?………………………………………………………………………………………………3

  • History
  • Why was the can opener invented?
  • How they did it?
    III. How a can opener works?………………………………………………………………………………..6
  • Instructions of how to use it.
    IV. Graphics ………………………………………………………………………………9
  • Part of a can opener.
    o Handles
    o Crank
    o Traction Gear
    o Cutting Wheel
    V. Conclusion…………………………………………………………………………12
    VI. Bibliography……………………………………………………………………….13

Introduction
A can opener (in North American English and Australian English) or tin opener (used in British English) is a mechanical device used to open tin cans (metal cans). Although preservation of food using tin cans had been practiced since at least 1772 in the Netherlands, the first can openers were not patented until 1855 in England and 1858 in the United States.

History
The first practical can opener was developed 50 years after the birth of the metal can. Canned food was invented for the British Navy in 1813. Made of solid iron, the cans usually weighed more than the food they held! The inventor, Peter Durand, was guilty of an incredible oversight. Though he figured out how to seal food into cans, he gave little thought to how to get it out again. Instructions read: “Cut round the top near the outer edge with a chisel and hammer.” Only when thinner steel cans came into use in the 1860s could the can opener be invented. The first (patented in 1858), devised by Ezra Warner of Waterbury, Connecticut, looked like a bent bayonet. Its large, curved blade was driven into a can’s rim, then forcibly worked around its edge. Stranger yet, this first type of can opener never left the grocery store. A clerk had to open each can before it was taken away!

The modern can opener, with a cutting wheel that rolls around the rim, was invented by William Lyman of the United States in 1870. The only change from the original patent was the introduction of a serrated rotation wheel by the Star Can Company of San Francisco in 1925. The basic principle continues to be used on the modern can openers, and it was the basis of the first electric can opener, introduced in December 1931. Pull-open cans, patented by Ermal Fraze of Ohio, debuted in 1966.

Why was the can opener invented?
The first tin cans were so thick they had to be hammered open. As cans became thinner, it became possible to invent dedicated can openers. In 1858, Ezra Warner of Waterbury, Connecticut patented the first can opener. The U.S. military used it during the Civil War.

How did they did it?
Fast forward to 1858 when iron cans began to be replaced by thinner steel cans, and not long after the first can opener was born. An American inventor, Ezra J Warner developed a blade that pierced the lid of the can, whilst another component sawed around the edge. The only downside to this is that once the lid was removed, it revealed a jagged rim of metal which posed itself as a significant health risk, a lot of people lost their fingers to that blade in the 1860s.

This is the can opener that Ezra Warner developed.

Fig 1. Ezra’s Can Opener

How a can opener works?
Simple can openers, like those found in pocketknives, are operated by walking the device around the edge of the can while digging into the lid. The lid will have very jagged edges after removal.

Most can openers press a cutting wheel into the edge of the lid while a rough support wheel presses up under the lip of the can. can opener that drives with that support wheel can provide easier motion. Non-electric can openers with this feature can be identified by a set of gears behind the cutting and support wheels. The pictured can opener has such gears, with 2 or 3 teeth visible peeking out above the cutting wheel near the bottom of the picture. Some more unusual can openers cut into the side of the can, often within the seam area so that a nice lid is formed. The lid is not very sharp and does not fall into the food. In this case, the support (and possibly drive) wheel run around the inside edge of the lid as the can is opened.

This are a few instructions of how to use a can opener.

  1. Open the arms of the can opener.
  2. Put the cutting edge of the can opener on top of the lip of the can lid.
  3. Close the arms of the can opener to puncture the lid of the can.
  4. Twist the can opener handle to rotate the cutting edge around the lid.
  5. Lift the lid from the can to remove it.

Graphics
Parts of a can opener.

Handles
The body of a manual can opener consists of two handles connected with a single rivet or bolt, allowing them to be drawn apart and pushed together, pivoting on the point where they are joined. Higher quality can openers have rubber grips on the handles, making them easier and more comfortable to grip.

Crank
A crank that can be turned by hand is attached to one of the handles. The axle of the crank goes through the handle and has the traction gear attached to the other side. When you use the can opener to open a can, you separate the handles of the opener, place the traction gear beneath the lip of the can and the cutting wheel above it, then bring the handles together, trapping the lip of the can between the traction gear and the cutting wheel. With the opener in this position, you can turn the crank to turn the traction gear and propel the cutting wheel around the rim of the can.

Traction Gear
The traction gear is a small, round metal wheel with notches in it to increase its grip on the lip of the can. When it and the cutting wheel are pressed tightly against opposite sides of the lip of the can, the pressure against the surface of the traction gear causes it to grip the surface of the metal can when you turn the crank.

Cutting Wheel
The cutting wheel has a sharp edge around its circumference. When you force the cutting wheel against the metal of the can by pushing the handles of the opener together, its sharp edge cuts through the metal. When you turn the traction gear by rotating the gear, the cutting wheel rotates as well, cutting through the metal as it advances around the lip of the can.

In conclusion the can opener is used to open cans of preserves and canned food. Can openers have evolved, although the original model from 1870 has remained unchanged. This is still used today and although there is electric can openers, many people still choose to buy the manual can opener.

Bibliography
Wikimedia Foundation. (2022, September 26). Can opener. Wikipedia. Retrieved September 29, 2022, from https://en.wikipedia.org/wiki/Can_opener
Ament, P. (2000, January 1). Can opener history. Can opener history – invention of the can opener. Retrieved September 29, 2022, from https://web.archive.org/web/20100102140415/http://ideafinder.com/history/inventions/canopener.htm
Bellis, M. (2019, April 4). Love the longevity of canned food? thank this guy. ThoughtCo. Retrieved September 29, 2022, from https://www.thoughtco.com/history-of-the-can-and-can-opener-1991487#:~:text=The%20first%20tin%20cans%20were,patented%20the%20first%20can%20opener.
Wikibooks, (2018, November 20) Cookbook:can opener. Wikibooks. Retrieved September 29, 2022, from https://en.wikibooks.org/wiki/Cookbook:Can_Opener
wikiHow. (2021, August 4). 3 ways to use a can opener – wikihow life. 3 Ways to Use a Can Opener – wikiHow Life. Retrieved September 29, 2022, from https://www.wikihow.life/Use-a-Can-Opener#:~:text=The%20two%20long%20arms%20that,early%201800s%20by%20an%20Englishman.
wikiHow. (2020, September 7). How to use a manual can opener. 10 Steps (with Pictures) – wikiHow Life. Retrieved September 29, 2022, from https://www.wikihow.life/Use-a-Manual-Can-Opener#/Image:Use-a-Manual-Can-Opener-Step-5-Version-11.jpg