A screwdriver is a common tool used to turn screws in place, usually with a thin wedge head that can be inserted into the slot or notch of the screw head.
Beijing-tianjin-hebei Lujin and Shaanxi northern Shaanxi and northern Henan dialect known as “screwdriver”, more northern Henan is called screwdriver, Jiangxi, Anhui and Hubei, Henan south of the Yellow River, Shaanxi Guanzhong and other places known as “screwdriver”, the central and western regions known as “change knife”.
There are two main types: a word (negative sign) and a cross (positive sign). There are also common hexagonal screwdrivers, including inner and outer hexagonal two kinds.

Technical Principles

The screwdriver uses the working principle of lever when it is used to pry paint covers. The greater the distance from the power point to the fulcrum, the less effort, so longer screwdrivers are more labor-saving than shorter screwdrivers.
Screwdrivers take advantage of the working principle of a wheel shaft when they are used to screw. The larger the wheel, the less effort, so it takes less effort to turn the screw with a screwdriver with a thick handle than with a screwdriver with a thin handle.

Commonly Used Information

Often used to screw

Evolution of history

The Phillips screw and Phillips screwdriver were invented by Henry Phillips in the 1930s. It was first used on the assembly line of automobiles. So Phillips screws and Phillips screwdrivers are also known as Philips screws and Philips screwdrivers.
In order to give a little twist to the screw, people think of a slot in the screw head, with the corresponding zigzag screwdriver can easily tighten and loosen the screw, but with the rapid development of science and technology, screws are more and more widely used, screw and flat-head screwdriver deficiencies also appear. The first is that once the groove of the screw head is damaged, the screw can not be screwed out. The longer the slot, the more likely it is to be damaged in the process of being screwed.
In order to shorten the length of the notch, improve the ability of the notch to resist damage, and transmit the same torsion force, people think of using a cross groove, which can bear the same torsion force, but the length of a notch is half shorter, and the ability to resist damage is greatly strengthened. The screwdriver is originally shaped like a shape and cannot be used for the cross slot screws. Only another kind of Phillips screwdriver corresponding to the cross slot screws is produced. So you have two screwdrivers.

Slotted screws have been in use since the beginning of the machine. It’s impossible to replace all the screws on the old machine. The Phillips screwdriver cannot be used on the slotted screw. The slotted screw is still in production, so keep the flat-head screwdriver. Thus, most of the new machines use the cross notch screws, and the old ones are still in use, so there is a situation where both screwdrivers are used at the same time.

Basic Functions

When repairing a mobile phone, you need a screwdriver to open the case (some mobile phone cases are buttoned without a screwdriver). And the use of screws mostly with hex screws; Different mobile phones have different specifications, generally T5, T6, T7, T8 and so on, some models are equipped with special screws, need to use a special screwdriver. In addition, you will need some small flat-head, small plum screwdrivers.
In the selection of such tools, should choose A, B batch, it almost includes all mobile phone shell tools. When opening the case, the right screwdriver should be selected according to the type and specification of the fixed screws on the case. If the selection is not appropriate, it is possible to screw the groove flat, produce the phenomenon of slipping.

Main types


1. Common screwdriver
It is a batch of screws made together by the head handle. It is easy to prepare and can be used as long as it is taken out. However, because there are many different lengths and thicknesses of screws, sometimes many different batches of screws need to be prepared.
2. Combined screwdriver
A screw batch with a screw head and a handle separated. When installing different types of screws, you only need to replace the screw head instead of bringing a large number of screw batches. The advantage is that space can be saved, but easy to lose the screw batch head.
3. Electric screwdriver
Electric screw sets, as the name implies, use electric motors instead of manual screws to install and remove screws, usually a combination of screw sets.
4. Watch driver
It is a precision driver, commonly used in the repair of hand-strap watches, so it has this name.
5, small diamond screwdriver
The head handle and body length size is smaller than the commonly used screwdriver, not a clock driver.
In terms of its structural shape, it usually has the following types:
1. Straight shape. This is the most common kind. Head models have a word, cross, rice, T (plum), H (hexagonal) and so on.
2. L shape. Commonly seen in the hex screwdriver, the use of its longer rod to increase the torque, so as to save force.
3. T shape. Automotive repair industry more applications.
Head type
Type of screwdriver head:
Screwdriver according to different head types can be divided into a word, cross, rice, star (computer), square head, hexagonal head, Y head and so on, one word and cross is the most commonly used in our life, like installation, maintenance of this kind of need to be used, it can be said that as long as there is a screw where the screwdriver will be used.
Hexagonal head is not used much, commonly used hexagonal wrench, like some machines on a lot of screws with hexagonal holes, convenient for multi-angle force. The big star is not much to see. The small star is often used for dismantling and repairing mobile phones, hard disks, notebooks, etc. We call the small screwdriver clock batch, commonly used star T6, T8, cross PH0, PH00 and so on.
The head is: word SLOTTED
The rice word POZI
SQUARE square
HEXAGONAL hexagonal

Make the material

Screwdrivers don’t have round heads because they have no torque at all. The word is to ensure torque, and the cross allows the force to be distributed more evenly. According to the power source to be divided into manual screwdriver and electric screwdriver; There is a flat head and a phillips cross according to the head or knife head.
The tip of a good quality screwdriver is made of a stiff spring steel. A good screwdriver should be hard but not brittle, hard but tough. When the screw head opening becomes bald and slippery, you can use the hammer to knock the screwdriver, the screw slot pick deep, easy to screw off, the screwdriver should be intact; Screwdriver is often used to pry things, it requires a certain toughness does not bend or break. In general, it is hoped that the hardness of the screwdriver head is greater than HRC60, and it is not easy to rust.


Align the specialized shaped end of the screwdriver with the top pit of the screw, secure it, and start rotating the handle.
According to the specification standard, clockwise rotation for clamping; If it is rotated counterclockwise, it is loose. (In rare cases, the opposite.)
A line screw batch can be applied to cross screws. But the cross screw has a strong ability to resist deformation.

Maintenance Measures

(1) The blade of the screwdriver must be properly ground, and the two sides of the blade should be as parallel as possible. If the blade is tapered, it is easy for the blade to slip out of the screw notch when turning the screwdriver.
(2) The head of the screwdriver should not be ground too thin, or ground into any shape other than square.
(3) Be very careful when grinding the screwdriver on the grinding wheel. It will overheat and make the edge of the screwdriver soft. Wear safety goggles when grinding.