The keyboard is an important computer input devices, to carry a large amount of information input tasks. Keyboard has undergone a series of development process, the number of keys on the keyboard 83 key development from the earliest to 101,102,104 key later, Windows 95 Standard Natural Keyboard, with the Windows version of escalating appeared on the market 108 key Windows keyboard compared with 104 keyboard, the keyboard function key area 108 more Power (power switch), Sleep (into sleep) and WakeUp (sleep wake up) three functions
Used in the main computer keyboard similar to the English typewriter keyboard, from the looks of it, the computer keyboard is divided into four districts typing keypad, function keypad, editing keypad and the numeric keypad and the like.
First, the typing keypad: The most common location on the keyboard, including:
1. Digital: Key: (10 digits).
2. English alphabet keys: (26 letters of the alphabet).
3. Shift key: on both sides of the middle part of the keyboard, each with a shift key when there are two symbols on the keys, first press and hold the Shift key, you can display the symbol above the key.
4. Symbol keys: representative mathematical symbols addition, subtraction, multiplication, division and involution.
5. Blank key: the longest keyboard keys each press a blank character.
6. Abdicated key: key to delete the cursor to the left of the characters, all the words back also moved forward.
7. Case conversion keys: keys to convert the English letter case.
8. Wrap keys: keys, also known as the Enter key, the command or data will be sent to the input of computer processing.
9. Control keys: keys and other keys generated with the control functions such as hold first press may issue a "beep".
10. Conversion Key: Another key control keys, you can change the key of the original features.
Second, the function key area:
A total of 12 function keys on the keyboard, which are located above the keyboard. In accordance with the characteristics of different software can be set commonly used keys or commands to the function keys.
Third, the numeric keypad:
In the numeric keypad to the right of the keyboard with numeric key functions and editing key functions.
1. Number Lock keys: keys are used to switch the numeric keys and editing keys function.
2. Insert the key: the key is inserted and replaced with two switch key input mode.
3. Remove the key: the key to delete the character at the cursor, the right word will automatically fill up.
4. Wrap the key: the same key wrap function keys and typing keypad.
Fourth, editing keypad:
In the middle of typing and editing keypad has a numeric keypad editing keypad, with a spot for editing the total of the arrow keys and the Insert key, delete key, Home key, end key, Previous key Next key, etc. .
1. Arrow keys: four keys, the cursor can, down, left, right.
2. Insert the key: key (the same).
3. Remove the key: the key (the same).
4. Homing key: key cursor jumps to the top of the column, so write more quickly.
5. End key: key to move the cursor to the column's last word to the right information.
6. Jumped off the key: the key to jump out feature is currently being executed or canceled input.
7. Previous keys: keys, so that the screen turned up one.
8. Next key: the key to make the screen turn down the page.
Keyboard and mouse, are easy to wear equipment, a comprehensive interpretation of your keyboard, understanding the structure of the keyboard, a comprehensive grasp of general fault repair method is necessary
Open backplane common Windows keyboard, you can see the keyboard consists of several parts keyboard chassis, a polyester film printed circuits, circuit boards, keys, keyboard cover, signal lines and other components. Keyboard generally made of a hard resin plate material, good keyboard is a metal plate bottom, the keyboard to increase the bearing capacity. A set of keyboard keys are arranged in a matrix manner by a key switch consisting of a polyester film of a printed circuit printed on a transparent polyester film with a conductive coating is made of silver.
Polyester membrane keyboard printed circuit is the most critical component is the input information of the recipient; most keyboards are basically using this approach work. This is embedded in the base plate on the keyboard for the three-layer structure of the polyester film, the upper and lower layers at the opposite side of the printed conductive coating as a key contact layer, the intermediate layer is not electrically conductive coating for the barrier layer. On the intermediate layer and the corresponding button on the lower place to play around some 8mm diameter hole, The role of this round hole when the key is pressed, the upper and lower contacts will contact occurs, which is the key keyboard work, usually pops up when the button, the middle layer of polyester film between the upper and lower spaced upper and lower distance
When the key is pressed, a slight deformation of the upper polyester film through the intermediate layer and the lower conductive layer connected to the hole,
This will accept key information, resulting in signal transduction. Reset button is suspended by springs or elastic rubber pad to complete. Different keyboard rubber pad design is different, probably two types, one is independent of each key separately, one is designed to press the keyboard keys integrally connected
Conductive coating on the polyester film is generally silver conductive material, in hot, humid work environment is relatively easy to aging, and the aging of the conductive coating will be yellow, black, infinite resistance increases or complete rupture, loss of conductivity
The key is embedded in the keyboard lid moves up and down in the hollow cylinder,
The key is to maintain the lower end surface of the keys and buttons work properly reset the suspension springs or elastic rubber pad, the keyboard is now commercially available mulch-purpose rubber mat
In the upper right corner of the keyboard lights work, there is a small circuit board,
The keyboard circuit board is a "heart" by a plurality of electrical components, a plurality of signal lines and the interface chips, etc., which is the hub of the keyboard to transmit information.