The Main Components Of Copy Machines

By Phyllis P. Kinder


Photocopiers, also known as copiers or copy machines, are devices that make copies of visual images and other documents on paper. The process is both fast and cheap. Most of these devices use a technology called xerography or ink jet.

James Watt is responsible for invention the first office copy machine in 1779. His invention was able to copy items by transferring ink used in the original to other papers by way of a moistened paper and a press. The device was successful for its time and continued to be so for a century. When Chester Carlson invented electrophotography, a process that led to the development of copying devices as we know them today.

Photocopying is a common practice within business, education and government organizations. Digital documentation is becoming more popular. So much so that many believe photocopiers will no longer exist, especially when there is less reliance on physical documentation.

Generally, photocopying done in an office involves xerography. This technology was introduced in 1959 by the Xerox company. It would eventually replace copies made using other duplicating devices and techniques, such as mimeograph machines, carbon paper, Photostat, and Verifax.

Photocopiers that use this technology go through a five-step process. The first step is charging. This is when the cylindrical drum, which is covered by a photoconductive material, is electrostatically charged. This is done using a high-voltage wire called a corona wire or charge roller.

In the exposure step, a bright lamp illuminates the original copy. White areas on the original reflect light onto the drum surface, which is photoconductive. If the area has been exposure to the light, it is considered conductive and will discharge to the ground. If the area has not been exposed to light, it will continue to have a negative charge. This step results in a latent image placed on the drum.

During the developing process, positively-charged toner is applied to the drum and attaches to areas that have a negative charge. In the transfer step, the toner image that is on the drum surface is transferred to paper with a high negative charge. Then, there is the fusing process. This is when the toner is melted and bonded to paper using pressure rollers and heat.

Copy machines are devices used to make copies of documents or visual images. They may use technology such as ink jet or xerography, though xerography is most commonly used, especially in office copying. This process works through five steps: charging, exposure, developing, transfer and fusing. Devices similar to photocopiers have existed since the eighteenth century.




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