What Is a Keyboard Circuit Board?

A keyboard is a type of instruction and data input device used to operate a device. It also refers to a group of function keys (such as a typewriter and a computer keyboard) arranged to operate a machine or device through the system. The keyboard is also a part of a keyboard instrument. It can also refer to a musical instrument that uses a keyboard, such as a piano, digital piano, or electronic keyboard. The keyboard helps to practice typing.

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keyboard

The keyboard alphabetical order is sorted according to the frequency of alphabet usage. Attentive readers may be wondering: why should this 26-letter arrangement be irregular? It is difficult to remember and proficient. The reason is said to be this:

In the 1870s, Shoals was the largest manufacturer of typewriters at the time. Because the mechanical technology was not perfect at the time, the rebound speed of the word keys was slower after the stroke. Once the typist's keystroke speed is too fast, it is easy for two word keys to be twisted together. You must carefully They are separated, which seriously affects the typing speed. Therefore, the company often receives complaints from customers.

In order to solve this problem, a smart engineer proposed: The reason for the typewriter twist key is that the word key rebounds slowly on the one hand, and the typewriter is too fast on the other. Since we can't increase the bounce speed, why don't we want to reduce the typing speed?

There are many ways to reduce the speed of a typist. The simplest way is to shuffle the order of the 26 letters and place the more commonly used letters under the clumsy fingers. For example, the letters "O", "S", "A" The most frequently used, but the most clumsy right ring finger, left ring finger and left pinky to hit. The letters "V", "J", "U", which are used less frequently, are handled by the most flexible index finger.

As a result, the keyboard of this "QWERTY" combination was born and gradually shaped. Later, due to the development of material technology, the rebound speed of the word keys was much faster than that of a typist, but the keyboard alphabet order could not be changed. Although there are many more reasonable alphabetical design schemes, none of them can be promoted. We can see how powerful the habitual power of society is.

The universal 101-key or 102-key keyboard is named according to the arrangement of English letters and is called a QWERTY keyboard. Needless to say, it was born out of an English typewriter.

First, laser etching

The so-called laser etching is to use laser lettering technology to burn out black grooves on the keycap. Because the engraved marks are linear, the arrows on the common laser-etched keyboard are hollow.

But laser etching also has several fatal flaws, which also determines that it cannot be used in the production of high-end keyboards. First, because laser etching is etching, and no ink is used, only a single black font can be printed, so the multi-color overprint design often found on high-end keyboards cannot be achieved. The need for durability, ergonomics and other non-standard structure products are difficult to print on ordinary laser etching machines. Because of this, in the production lines of large factories, laser etching is only used in low-end production lines to take advantage of its fast production speed and low cost; while in high-end product production lines, due to higher printing quality Requirements, so can only continue to use the traditional high-cost ink printing method.

Second, the pad printing method

Pad printing is a very old method of keycap printing, which is no longer used because it is less practical and less efficient. The pad printing method is to use a set of letter lead letters as the original type. After it is brushed with ink by an automatic machine, a set of soft rubber blocks is pressed on it, so when the rubber block is lifted, the handwriting ink will be transferred to On the rubber block, and then move the rubber block to the blank keyboard, as soon as the rubber block is pressed, the ink is printed on the keyboard.

Screen printing (a common method in ink printing)

The principle is to cover a special screen with a blank keyboard, where the handwriting is hollowed out, and then scrape the ink from above, so that the handwriting will be printed on the hollowed out part. The characteristic of silk screen printing is that after the handwriting is printed, a special layer of plastic can be used to apply a layer of plastic. After drying, a plastic protective film covering the printed handwriting will be formed, which can prevent long-term use of the handwriting. Wear, which is also known as keyboard overlay technology. The English terminology of this plastic is: Coating. Compared with laser etching, screen printing can print multiple colors freely through repeated overprinting of multiple screens, and there is no restriction on the keyboard material. However, due to the limitation of its printing method, it is still impossible to print a keyboard with an overly complicated shape.

Fourth, impregnated printing (also known as sublimation method)

Impregnation printing is a completely different printing method from ordinary ink printing. It does not use common liquid pigment inks, but solid resin inks. This ink will sublimate into a gaseous state at high temperatures, and infiltrate into the permeable print surface in the form of gaseous molecules, and then condense, so as to be physically integrated with the printing surface, not just "sticky" like ordinary pigment inks On the printing surface, so its printing fastness is extremely high. In addition, resin inks are inherently superior in terms of gloss and morphology.

Five, laser filler method

The principle of laser filler method is similar to "tattoo". Tattoo is to use a needle to make fine lines on the skin, and then fill it with pigment, so that the color will penetrate into the skin's lines, and it will not be washed off or rubbed in the future. Off. The same is true for laser filler technology. First, use laser etching technology to print the text once (but lighter than usual laser etching to ensure the surface is flat), and then use ink printing to perform secondary printing, so that the cured ink will be Infiltrated by the laser and left in it, it will not be easily worn away afterwards. The keyboard printed with laser filler technology, because of the secondary printing of the ink, makes up for the defects of poor laser etched fonts and inability to print colors. Because of the laser scoring as a basis, its robustness is much higher. For simple ink printing. Personally, this keycap treatment method is a combination of laser etching and ink printing.

Six, hollow printing

First of all, it is explained that this method is almost all printed in this way on the keyboard of the mobile phone. And only some notebook keyboards of APPLE have used this printing method. This printing method is simple to say, in fact,

Keyboard repair

1. "The keyboard cannot be found when the computer is turned on" fault repair

There are many factors that cause the keyboard not to be searched at startup. For example, the connection is not strong, the keyboard interface is damaged, the wiring is defective, or the motherboard is damaged. For this kind of failure, usually shut down first, unplug the keyboard connector, and then plug it into the keyboard interface on the motherboard.

2. "Keyboard Key Failure" Repair

The keyboard keys fail. This phenomenon usually occurs because there is dirt on the circuit board or conductive plastic, which makes it impossible to connect between the two. Other factors are also possible, such as: damaged keyboard plugs, defective wiring, damaged motherboards, and abnormal CPU operation, but this is not the main reason. Therefore, only descaling is required.

The operation steps are as follows (note that the scissor keyboard is mainly used for notebooks that are superbook-type keyboards. Do not disassemble them when you press the keyboard for personal maintenance or you cannot replace them):

1. Disassemble the keyboard. Note that when opening the keyboard, make sure that the side of the button (that is, the side we are operating on) is facing down and the circuit board is facing up, otherwise the conductive plastic on each key will fall off one after another, bringing trouble to your repair.

2. Open the circuit board. The circuit board is generally made of soft plastic film with button cords engraved on it. Use a cotton with a concentration of preferably 97% or more or 75% medical alcohol cotton to gently scrub the circuit board. . Wipe the circuit of the button failure part several times.

3 Check the conductive plastic on the malfunctioning part of the button. If there is a lot of dirt on the upper area, use alcohol to scrub it. Assuming that the conductive plastic is damaged, it is recommended to replace the conductive plastic on the unused keys with the damaged part. Although this measure cannot make the keyboard perform all the functions, it can at least extend the life of the commonly used keys.

4 Remove dirt from the inner corners of the keyboard. Tools can be brushes, small brushes, etc., but be careful to move gently.

5. Check the soldering module for virtual soldering or desoldering. If you use an electric soldering iron, you can perform repair welding. Of course, this step is only applicable to friends who can use the electric soldering iron, friends who will not use it, please skip this step.

6. After installing the keyboard, one thing to note here is that you must wait for the alcohol to evaporate before proceeding.

Keyboard disinfection

1. Tap the keyboard. Shut down the computer and remove the keyboard from the main unit. Put a newspaper on the table, turn the keyboard down, about 10 cm from the table, and pat and shake.

2. Blow off debris. Use a hair dryer to blow on the gaps on the keyboard keys to blow off the debris, then turn the keyboard down again and shake it.

3 Scrub the surface. Use a soft cloth dampened with diluted detergent (make sure the soft cloth is not too wet) to scrub the surface of the keys. Then vacuum the keyboard again with a vacuum cleaner.

4 disinfection. After the keyboard is cleaned, it may be dipped in alcohol, disinfectant or medicinal hydrogen peroxide for disinfection, and finally wipe the surface of the keyboard with a dry cloth.

5. Wash thoroughly. If you want to clean the keyboard completely, you have to remove the cap of each key. The keycaps of ordinary keyboards are removable, and you can pry them off with a small screwdriver or an ear spoon. Larger keycaps such as the space bar and the enter key are difficult to return to their original positions, so try not to remove them. It is best to use the camera to take a picture of the keyboard layout or draw a sketch. After removing the keycap, you can soak it in detergent or disinfectant solution, and carefully scrub the keyboard base with a velvet cloth or disinfectant paper towel.