Looking back at the development history of printers, we can clearly see the development trend of printers: from impact to non-impact, from black and white to color, from single function to multi-function, there are different classification methods for many printer brands. At present, there are two commonly used classification methods: one is to classify according to principles, and the other is to classify according to purposes.
1. Classification by principle
According to the working principle of printers, printers can be divided into two categories: impact type and non-impact type, as shown in figure 1- 1.
Non-hitting type
affect
Serial type
needle type
Word diagram
lineshape
Arrangement type
Word diagram
Serial type
Heat sensitive type
Electrocautery type
Thermal transfer type: hot melt type, dye sublimation type.
Inkjet type
lineshape
Heat sensitive type
Electrostatic type
Inkjet type
Page style
Magnetic type
Other ways
Ionic type
Optical type: laser type, LED type and LCS type.
Thermal transfer type: hot melt type, dye sublimation type.
Author: Epson 2005-5-1521:48: 00)
2. Classification by purpose
With the rapid development of information technology in today's society, the application fields of various printers have developed in depth. From the grade, applicable object and specific use of the printer, it has formed universal, commercial, special, household, portable and network products.
L general office and business printers
In this application field, the stylus printer has always occupied a dominant position. Because the stylus printer has the characteristics of medium resolution, fast printing speed, cheap consumables, high-speed line skipping, multiple copies printing, wide format printing and convenient maintenance, it is still the first choice for printing reports and invoices in office and transaction processing.
L commercial printer
A commercial printer refers to a printer used for commercial printing. Because this field requires high printing quality, sometimes it needs illustrated documents, so a high-resolution laser printer is generally chosen.
Special printer
Special printers generally refer to various miniature printers, passbook printers, plane bill printers, bar code printers, thermal printers and other printers used in special systems.
L home printer
A home printer refers to a printer that enters the home with a home computer. According to the characteristics of home printers, low-grade color inkjet printers have gradually become mainstream products.
L portable printer
Portable printers are generally used for supporting notebook computers, with the characteristics of small size, light weight, battery-driven and easy to carry.
Author: Epson 2005-5-1521:48: 00)
L network printer
Network printers are used in network systems to provide printing services for most people. Therefore, this printer is required to have the characteristics of fast printing speed, automatic switching between analog mode and network protocol, and convenient management by network administrators.
Second, the printer principle Different types of printers not only have different physical structures and application fields, but also have essential differences in printing principles and printing technologies. The following is a description of the working principle of the needle printer, inkjet printer, laser printer and thermal conversion printer which are widely used in the printer field today.
Before describing the working principle of the printer, first introduce how the printer prints Chinese characters. Printers usually have two printing modes, namely text mode and graphic mode. Western languages are printed in words, and Chinese characters can be printed in words and graphics. For printers, it can be divided into two types: one with Chinese character library and the other without Chinese character library. For a printer with a Chinese character library, you can receive the internal code of Chinese characters transmitted by the computer through text and print it directly. This kind of printer is usually called a Chinese character printer. Printers without Chinese character library are usually provided by Chinese character operating system, but the printing speed is slow and the efficiency is low.
1 stylus printer stylus printer is characterized by simple structure, mature technology, good cost performance and low consumption cost. Although the stylus printer has high noise, low resolution and easy damage to the printing needle, in recent years, due to the development of technology, the printing speed of the stylus printer has been greatly improved, the printing noise has been reduced, and the printing quality has been improved. The stylus printer has developed in the direction of specialization and specialization, which makes it play an irreplaceable role in the application fields such as bank passbook printing, financial invoice printing, scientific data continuous printing, bar code printing, fast jump printing and multiple copies.
At present, there are mainly 9-pin and 24-pin stylus printers on the market. The basic function of 9-pin Chinese character library is to print letters and numerical symbols. If you want to print a simple Chinese character composed of 16× 16 lattice, you can only print it graphically, and the printing must be done twice, that is, eight points are printed on the upper part of a line of Chinese characters for the first time, and eight points are printed on the lower part of the line for the second time, and the upper and lower parts are combined into a complete line of Chinese characters. Obviously, the speed of printing Chinese characters is very low; If you want to use it to print Chinese characters composed of 24×24 dot matrix, it will take at least three times to print a complete line of Chinese characters, and the printing speed will be slower.
According to the relevant standards, the definition of "Chinese character stylus printer" is: one or more printers that meet the requirements of international Chinese character font lattice can print at one time through the print head. At present, the popular 24-pin printer on the market can print Chinese characters composed of 24×24 dot matrix at a time.
The western stylus printer itself has no Chinese character library, but is set on the hard disk of the computer system. When processing Chinese character information, with the support of Chinese character operating system (CCDOS), the dot matrix code in the hard disk Chinese character library is called according to the Chinese character input code, and the host computer sends the read dot matrix code to the printer in the form of dot matrix image. For a Chinese character composed of 24×24 dot matrix, the host will send the corresponding 72-byte dot matrix code to the printer. Obviously, not only the host is busy with Chinese character conversion, but also the dot matrix code is constantly transmitted between the host and the printer, which greatly reduces the working efficiency of the system. For a printer with its own Chinese character library, when the computer processes Chinese character information, the host only needs to send the Chinese character national standard code (two bytes) directly to the printer, and the Chinese character national standard code is converted into the corresponding dot matrix code, which is completed by the printer. Compared with the two, the host computer processes a Chinese character, shortening the output of 72-byte dot matrix code to 2-byte national standard code, which greatly improves the working efficiency of the system. The software and hardware inside the printer can also complete the functions of vertical printing, horizontal amplification, vertical amplification, italic printing, hollow printing, reverse printing, black printing and so on. So as to give full play to that function and prin speed of the Chinese character printer.
Author: Epson 2005-5-1521:49: 00)
1. 1 The basic working principle of the stylus printer is to use the mechanical and circuit driving principle to make the printing needle hit the ribbon and the printing medium, and then print a dot matrix, and then the dot matrix forms characters or graphics to complete the printing task. When the printer is online, it receives the printing control command, character printing or graphic printing command sent by the PC through the interface, and after being processed by the printer CPU, it looks for the first column address (when printing in the forward direction) or the last column address (when printing in the reverse direction) of the image code corresponding to the character or graphic from the font, finds out the code column by column, and sends it to the print head driving circuit to stimulate the print head to print in the needle printer.
The basic printing steps of the stylus printer are as follows: start the printer carriage → check whether the print head enters the printing area → initialize printing → drive the print head to print a column according to the character or graphic code → generate the column spacing → generate the word spacing → print a line, then start the paper feed motor to drive the print roller and printing paper to enter a line → enter a line (enter in case of unidirectional printing) to prepare for the next line printing. In this way, the stylus printer is controlled by the monitoring program to complete the printing work.
In terms of structure and principle, the stylus printer consists of two parts: printing mechanism and control drive circuit. In the printing process, there are three kinds of mechanical movements: the lateral movement of the printing head, the longitudinal movement of the printing paper and the injection movement of the printing needle. These movements are controlled by software and driven by some precision machinery.
The mechanical device of the stylus printer includes:
(1) print head drive mechanism (carriage mechanism)
The mechanism adopts stepping motor and gear reducer, and synchronous toothed belt drives the front carriage to move laterally;
(2) the print head
The printing head is a printing mechanism and a word-forming part, which consists of a plurality of printing needles and a corresponding number of electromagnets, and the electromagnets can drive the printing needles to complete the striking action;
(3) Ribbon drive mechanism
One-way circulating ribbon mechanism is widely used in stylus printers. When the print head moves left and right, the ribbon drive mechanism drives the ribbon to move left, which can not only change the impact position of the ribbon, but also ensure the uniform wear of the ribbon, prolong the service life of the ribbon and ensure the consistent color depth of printed characters. Ribbon is usually made of ribbon nylon or film coated with black or blue ink.
(4) Paper feeding mechanism
The paper feeding mechanism is a mechanism that drives the printing paper to move longitudinally to realize line feed.
The paper feeding mechanism of stylus printer is generally divided into friction paper feeding and gear paper feeding. The former is suitable for printing paper without paper feeding holes. The latter is suitable for printing paper with paper feed holes. When the print head finishes printing one line (regardless of the number of characters), the paper feeding mechanism will immediately complete one or more lines of paper;
(5) printing state sensing mechanism
The state sensing mechanisms of different stylus printers are different, generally including paper end sensing mechanism, manuscript position sensing mechanism and timing sensing mechanism.
The frame of stylus printer is mainly composed of left and right wall plates, electrical assembly frame and base. The whole shell is made of plastic compression molding, which is fully enclosed for dust prevention and noise reduction.
Microprocessor, ROM and RAM memory are widely used in the control drive circuit of modern stylus printer. Among them, ROM is mainly used to store the management program, font library and Chinese font library of the stylus printer. Without Chinese character library, the capacity is generally above 10KB. With Chinese character library, the capacity is even greater. RAM is mainly used as a buffer for printers to receive host information data. One part of RAM is used to store the character set from rom after the initialization of the stylus printer, and the other part is used for dynamic parameter exchange during program execution. The RAM of different stylus printers is different. The RAM of Chinese pin printers is generally tens of KB, while that of non-Chinese pin printers is generally only about 1KB. Obviously, modern stylus printers can not only control their own printing tasks, but also print Chinese characters independently.
Author: Epson 2005-5-1521:49: 00)
1.2 main classification of stylus printers There is no obvious difference between various types of stylus printers, but with the need of specialization and specialization, different types of stylus printers have emerged, including universal stylus printers, passbook stylus printers, line stylus printers and high-speed stylus printers. The following focuses on the characteristics, performance and technology of these printers.
(1) universal stylus printer
China's "Universal Needle Printer" was a widely used Chinese character printing equipment in the early days. The number of needles in the print head is generally 24, which can be divided into wide lines and narrow lines. The print head slides back and forth on the metal rod to complete horizontal printing. The maximum printing width is 33cm, the printing speed is generally 50 Chinese characters per second (standard), and the resolution is generally 180dpi. The ribbon is used for printing, and the paper can be dragged and fed by friction, which can print both single-page paper and punched and folded continuous paper. Consumables such as ribbons and printing media are cheap. Due to electromagnetic impact, the print head generates serious heat when printing continuously for a long time, but the printing speed is not fast and the effect is not great; Moreover, because the universal needle printer is generally a wide-format printer, compatible with DOS system, it is especially suitable for ordinary offices and financial institutions with more report processing.
Universal stylus printers are easy to use. If the ribbon and paper are of poor quality or improperly installed, it is easy to break the needle. The printed words are too shallow, indicating that the coloring ability of the ribbon is reduced, which is easy to cause needle hanging and paper jam. At this point, the ribbon must be replaced. In addition, the ribbons of general-purpose needle printers are not uniform and cannot replace each other. The universal stylus printer has a manual adjustment lever to adjust the paper thickness. When the thickness of printing paper changes, the adjusting lever must be adjusted to adjust the printing depth and protect the printing needle.
(2) passbook pin printer
With the development of electronization in various industries, passbook pin printers specially used for counter business in banking, post and telecommunications, insurance and other service departments have been rapidly popularized and applied. The so-called passbook needle printer is also called bill needle printer. Compared with other general needle printers, passbook needle printers have the following characteristics:
L Flat push paper: The design of the flat push paper channel reduces the printing deviation caused by paper bending and paper jam, makes the paper advance and retreat freely, and makes it possible to handle ultra-thick printing media;
L Self-adaptive paper thickness: Passbook needle printer prints bills such as passbooks, and the thickness of different passbooks is different. Therefore, the passbook needle printer requires that the printing gap and impact force can be automatically adjusted according to the printing media with different thicknesses, so as to achieve a clear printing effect with any thickness;
Automatic rectification technology: it can automatically adjust the printing medium, greatly improve the printing accuracy and make the operator's operation extremely simple;
L paper positioning technology: in order to make the printing format neat and consistent, photoelectric sensors are installed on the bracket of paper transport vehicle to automatically detect the left and right boundaries of paper. A plurality of photoelectric sensors are arranged at the paper feeding mechanism to detect the top position of the paper, so as to ensure that the paper is absolutely flat relative to the printing bottom plate. Then the printing position is completely accurate through the printing positioning instruction in the printer control software;
L magnetic stripe reading and writing function: provide an optional built-in magnetic stripe reader, which can read and write the user's name, card number, amount and other information on the passbook, and support ANSI, ISO, NCR, IBM, Hitachi and other magnetic stripe formats;
L Print status identification: it has the function of two-way communication with the host or terminal, which can timely and accurately reflect the current status and errors of the printer and handle them accordingly. In addition, most passbook pin printers are specially designed to automatically stop printing when the cover is opened, which can prevent printing errors caused by human interference and protect personal safety.
L Other functions: Some high-end passbook pin printers also provide some optional functions, such as sharing printers between two operators, automatically recognizing bar code page numbers, printing cipher words such as magnetism, providing security decryption, printing special bank symbols, and automatically downloading and upgrading software by using Fresh-Rom storage technology.
The technical indicators for evaluating the passbook needle printer are mainly whether the equipment has good advanced paper processing ability, medium adaptability, convenience of operation, business processing speed, command simulation ability, simplicity of maintenance, durability of consumables and expandability of machine functions. In particular, the high-grade passbook printer should have the functions of automatic paper correction, automatic edge alignment and adaptive thickness printing, which can not only ensure the high accuracy of printing effect, but also make the operation extremely simple.
(3) Line needle printer
Line stylus printer is a high-grade stylus printer, which can meet the requirements of high-speed batch print business in banking, securities, telecommunications, taxation and other industries. Linear stylus printers have a strong tendency to print professionally, including special western printers and special Chinese printers. Compared with the general stylus printer, the line stylus printer has strong internal data processing ability. Because of the complex control of print head and paper feeding, master-slave dual CPU processing mode is generally adopted, which can greatly improve the printing speed and fully control the printing process.
The print head structure of linear needle printer is complex. In order to ensure that the linear needle printer will not break the needle due to overheating during continuous high-speed printing, the cooling mechanism inside the print head is very good. Linear needle printer has many printing needles and high frequency of needle output, so many effective measures and advanced technologies are adopted on the print head to reduce noise.
The key technology of line-pin printer is on the print head, and the output frequency of needle is as high as 2000Hz, which is more than twice that of general needle printer. Generally, the number of printing needles is 72, 9 1 needle, 144, and the most is 288, which is more than ten times that of a 24-needle printer. The print head of linear needle printer adopts modular structure (for example, the print head with 144 pins has 12 modules, and each module has 12 pins), and each module only needs to be responsible for horizontal printing for a short printing distance (generally about 1 inch), which is smaller than that of ordinary needle printers (generally more than ten inches).
The needle arrangement of printing needle module has great influence on the printing speed and performance of linear needle printer. Generally speaking, stylus printers can be divided into straight needle arrangement, oblique needle arrangement and parallel longitudinal arrangement.
Straight row means that the needles in the printing needle module are arranged horizontally and vertically. When the needle module moves horizontally left and right to print, it can only complete the printing distance of one horizontal point, and the printing height is1180 inch or1144 inch. The speed of the stylus printer in this arrangement can reach 1000 lines/minute. Therefore, the linear stylus printer is very suitable for printing and outputting western characters.
Oblique arrangement means that the needles in the printing needle module are obliquely arranged. When the needle module moves horizontally left and right for printing, the module can print several rows of horizontal dots with several needles. For example, the module of KD6000C line printer has 12 stitches arranged obliquely, and the speed of printing Chinese characters can reach 1000 Chinese characters per minute, which is more suitable for Chinese character output.
Parallel longitudinal arrangement means that the needles in the printing needle module are arranged in two parallel longitudinal rows, each module generally has 24 needles, and the speed is improved by adding multiple printing heads. This is an early line printing technology, and now it has been basically eliminated.
Line needle printer is a high-grade printer, and its printing needle life is more than 65.438+0 billion times per needle, but its life is affected by the quality of printing paper and ribbon.
(4) High-speed stylus printer
High-speed stylus printer is a product between ordinary stylus printer and line stylus printer, and its main feature is very fast printing speed. High-speed stylus printer is expensive, but it has high printing quality and high printing speed, and can bear a large printing load, which plays an important role in the fields of finance, post and telecommunications, transportation, batch processing of enterprise printing data and so on.
The "patent" of stylus printer is the function of carbon paper and continuous paper printing, and high-speed stylus printer also has this ability. At present, the replication capability of high-speed stylus printers is generally 1+4~ 1+5 layers, and it is better to reach 1+8 layers.