Home office has gradually become the normal work of many people, and home printers have become the necessary office electronic products for many families. As a computer output device, its function is to print and print the computer processing results on related media. A good printer usually has the characteristics of high printing resolution, fast printing speed, low noise, small size and convenience. Different technical solutions adopt different principles and devices for printers. In this issue, Heketai will explain the working principle and main components of commonly used household printers.

Generally, home printers have the characteristics of simple operation, easy installation and maintenance, low purchase price and consumables cost, versatility, small size, and support for wireless connection. There are ink-jet printers, which spray ink onto paper to form characters or images through ink-jet heads, laser printers, which use laser beams to form images on photosensitive drums, and then adhere to paper to form characters or images through carbon powder, and needle printers, which transfer ink to paper to form characters or images through the impact of printing needles on ribbons.

Here, Heketai mainly introduces how laser printer products work. It is a combination of laser scanning technology and electronic imaging technology, and its working imaging needs to go through the steps of paper feeding, charging, laser irradiation, development, transfer printing, fixing and cleaning to complete the output. The photosensitive drum is the core component of the laser printer, which is responsible for converting the laser signal into an electrostatic latent image. It is a cylindrical part with a layer of photosensitive material on its surface. Under the irradiation of the laser beam, the photosensitive material is charged, thus adsorbing the toner. The toner box is filled with toner, which is used to form a visible toner image in the printing process. The laser scanner is responsible for converting the digital signal into a laser signal and irradiating it on the photosensitive drum. The paper feeding system is responsible for sending the paper to the printer and sending it out after printing.

The laser printer is mainly composed of a laser printing system, which generates a laser beam for exposure on a photosensitive drum, a film conveying system, a motor and a power transmission system, which are used for storing films to be printed and printed, providing driving force for film transmission, and an information transmission and storage system, including a video interface and a digital interface, which is used for connecting imaging equipment to receive image information. The control system includes a keyboard, the control panel is used to input control instructions, such as printing program and format selection, the display panel displays the working status and error information of the printer, and the power management system provides stable current supply to the equipment. Other key components include photosensitive drum, toner box, fixing roller, cleaning system and so on.

The power management system, control system, motor and power transmission system and display board are the main parts used in household laser printers. They provide motor driving signals for the system and play the roles of voltage regulation and switching.

For example, MOS transistor can be used as a switching element in power management circuit to control the on-off of power supply and adjust the output voltage. Through accurate on-off control, MOS tube can effectively manage the power consumption of printer, prevent power overload or short circuit, and thus protect the electronic components of printer from being damaged. In addition, the paper conveying device and the photosensitive drum drive device in the laser printer need to be driven by motors. MOS tube can be used to drive these motors, and accurate paper conveying and photosensitive drum rotation can be realized by controlling the rotational speed and steering of the motors. In the motor drive circuit, MOS transistor is usually used as a power switch element, which can withstand large current and voltage, thus meeting the requirements of motor drive.

The control circuit of the laser printer needs to process the instructions from the computer and other input devices, and control the various components of the printer to work together. MOS transistor can be used as a logic switching element to form a MOS switching circuit, and signal transmission and processing can be realized in the control circuit.

In domestic laser printer products, MOS tube is mainly used as the core component of switch, driving and amplifying circuits, and the applied products usually have the characteristics of high drain-source voltage (usually more than 500V), switching speed, low on-resistance, high current tolerance, good durability, wide temperature range, high frequency, etc. The product models provided by Heke Taineng for such customers include HKTD4N50(TO-252 package), HKTD4N65(TO-252 package), HKTD5N20(TO-252 package), HKTD5N50(TO-252 package) and other products. These products have been verified by many printing customers, and the products are very stable and reliable.

At present, the household printer penetration rate in China is far lower than that in many developed countries. In the long run, China's household printer market has great room for growth, which is a very good market opportunity for discrete device manufacturers such as Heketai. Home printing opportunities are developing towards intelligence, networking, high efficiency, convenience, environmental protection and diversification. For components, the products provided by manufacturers should be more reliable and stable, with strong performance, wide temperature range, miniaturization, environmental protection, strong adaptability, durability and low power consumption.