1. Soft hand hammer

For the soft hand hammer, as the name suggests, the hammer head is made of soft materials, such as cowhide, wood, plastic or brass, as shown in Figure 1. In automobile maintenance operations, the soft hand hammer is commonly used to knock the required workpiece or metal sheet. Because the soft hand hammer is soft, the use of this hammer will not leave scars on the surface of the percussion workpiece. In the assembly of auto parts, a soft hand hammer can also be used to knock the parts to form a better coordination between the parts. For example, some car engines in the piston pin installed to the piston pin hole, you need to use a plastic hammer percussion installation; the use of rubber hammer also has a very prominent advantage, that is, when tapping the metal workpiece will not produce percussion sparks, so it can avoid igniting the maintenance site of gasoline, oil and other flammable items.

Figure 1 Soft hand hammer

2. ball hammer

Round head hammer, also known as fitter hammer, is a widely used tool in car maintenance. This hammer has a round head and a flat head at one end, as shown in Figure 2. The flat head is used to hammer the tools such as impulse or chisel, as shown in Figure 3. Round head is used for riveting and hammering pads. The specification of the round head hammer is generally expressed by the hammer head mass, such as 0.5kg, 0.75kg et al.

Figure 2 Round head hammer

Figure 3 tapping brass rod with round head hammer removing alternator front bearing

There are two kinds of hand hammer. As shown in Figure 4, the right fingers, the thumb is closed on the index finger, and the tiger mouth is aimed at the direction of the hammer. The other is the loose grip method, as shown in Figure 5, only the thumb and index finger always hold the hammer handle, while the other 3 finger relax the hammer, the ring finger, and the middle finger in the opposite order.

Figure 4 Hand hammer grip method

Figure 5 Hand hammer-loose grip method

In practice, according to the different requirements for the hammer force of the processing piece, there are three waving methods.

3. Combination hammer

A combined hammer is a hand hammer that combines a hard hammer and a soft hammer in one. The double hammer head design can be used flexibly, according to the work needs, so it is convenient and flexible to use, see Figure 7.

Figure 7 Combination hammer produced by American Blue Dot Company

4. bolt driver

A screwdriver, also known as a screwdriver or a screwdriver, is used to tighten or loosen a screw with grooves, see FIG. 8. There are wooden handle screwdriver, heart screwdriver, clip handle screwdriver and offset screwdriver, and can also be divided into one word screwdriver and cross screwdriver according to different screwdriver. Specifications are expressed by the length. When the screwdriver should adapt the bolt blade corresponding to the width, length and depth of the screw slot, as shown in Figure 9, and should not be used as a chisel or pry bar.

Figure 8. One-word screwdriver and a cross screwdriver

Figure 9. Remove the screw with a screwdriver

5. Pull the gear

The pull is a special tool used to remove the tight assembly, also known as the ama. Generally equipped with 2 to 3 claws, can pull the workpiece, with a screw, rotating screw gradually apply force to pull out the workpiece. As shown in Figure Figure 10. In automobile parts, some gears and shafts are very closely assembled, and some parts are also equipped with key pins to play a fixed role, so when disassembly of these parts, it is necessary to flexibly choose different pull tools according to the specific situation, to avoid damage to the gear during disassembly. Take LEXUS (Lexus) GS300 car as an example, when removing the engine crankshaft pulley, it is necessary to perform the disassembly operation, as shown in Figure 11; when removing the steering tie bar, because the steering cross bar and the steering section assembly are very tightly fastened, the pull is often used for disassembly, as shown in Figure 12.

Figure 10 Different types of pull

Figure 11 Removing engine crankshaft pulley (LEXUS GS300 car)