Inkjet Printers - A Brief Tour

If you’re like most inkjet printer owners, you only look inside your printer when the printer ink cartridge needs to be replaced. But the ink cartridge is just one element of a pretty complex mechanism -- let’s take a look inside your inkjet printer.

The print head

At the heart of your inkjet printer is the print head, which houses the nozzles responsible for spraying the ink onto the printer paper. Some printer manufacturers now build the print head into the ink cartridge, so as to keep the price of the printer itself down, and to increase the lifetime of the printer. The print head and ink cartridges (together, called the print head assembly) are pushed back and forth across the page by the stepper motor. The print head assembly travels across a stabilizer bar, to ensure even and precise motion.

Rollers

Paper is pulled into the printer from the paper tray or feeder by a pair of rollers, which control the rate at which the paper advances past the print head assembly. The rollers are powered by the paper feed stepper motor.

Twin inkjet technologies

Most inkjet printer manufacturers (including HP and Canon) use thermal bubble (bubble jet) technology to transfer ink to the page. In these printers, tiny resistors heat the printer ink to form bubbles. As these bubbles pop, ink is fired onto the page. Some other inkjet printers, including those manufactured by Epson, use piezoelectric technology instead. This technique involves a piezo crystal, housed in the ink reservoir of each nozzle, which is stimulated by an electric charge. That charge causes the crystal to vibrate, forcing ink out through the nozzle in which it is located.