一、The great invention—PHOTOCOPIER Hello, everyone! The
invention I'm about to speak is photocopier that almost everyone of you have already seen and known.
二、Introduction : As is known to all, a photocopier is a machine that makes paper copies of documents and other visual images quickly and cheaply.
Walk into almost any business office, and you'll probably find a photocopier with a line of people waiting to use it. For most businesses, small or large, the photocopier has become standard equipment, much like having a desk to work at and a chair to sit in. Nowadays ,we college students also more and more need to use it when necessary. Or worse, imagine how tedious it would be if you had to recopy everything by hand!
三、The inventor: Chester Carlson ,the inventor of photocopier. At the age of 12, he told his cousin Roy,"Someday, I'm going to make a great invention." Throughout his life, Carlson would walk from place to place with a notebook in his hand and jot down ideas for changing the world. He was always looking for ways to make life easier for people. Later while working as a patent analyzer, Carlson found the task of making hand copies of patent documents tedious. Since messy carbon
paper and ink mimeographs were ineffective ways to make high-quality copies, Carlson often had to rewrite and recreate the original documents by hand. This task was made more difficult by Carlson's nearsightedness and arthritis. He wanted to find an easier and more efficient way to complete this work.
Tinkering in a rented lab, Carlson discovered a process that could be used to put an image on paper. After gathering and combining the proper materials, Carlson came up with the invention of the electrostatic copying method in 1938. Sometimes, big companies can make big mistakes. When American inventor Chester Carlson approached some of the
world's largest corporations with his idea for a photocopying machine, during the 1940s, they simply didn't want to know. They couldn't imagine who would want to make lots of copies of documents. It took Carlson years to turn the idea into one of the most important office inventions of the 20th century. So, those companies kicked themselves when they realized just how big an opportunity they'd missed.
四、Next,Let us acquaint ourselves with the photocopier's working
principle. As a kid, you probably played with static electricity and balloons. On a dry winter day, you can rub a balloon on your sweater and create enough static electricity in the balloon to create a noticeable force. For example, a balloon charged with static electricity will attract small
bits of paper or particles of sugar very easily. What happens inside the copier at this point is amazing! At its heart, a copier works because of one basic physical principle: opposite charges attract.
There is a special drum inside a copier. The drum acts a lot like a balloon. You can charge it with a form of static electricity.
There is also a very fine black powder known as toner inside the copier. The drum, charged with static electricity, can attract the toner particles.
五、The basic steps to use :The working principle may sound complicated. But, the usage is very simple. I think ,We had better know well the basic steps to use when we have to run off copying personally.
First,open the copier lid.
Second, place the document to be photocopied face-down on the glass. Then, select the options you want,such as number of pages, enlargements, and so on.
Last, press the Start button.