Household jacks are usually simple in design, and can be divided into rack jacks, mechanical jacks, hydraulic jacks and heavy air jacks. It is often used when changing tires and checking the condition of the chassis.

Considering the space problem, family cars generally put their own jacks under the trunk, and we can see by opening the lower partition of the trunk. Household jacks are usually simple in design, and can be divided into rack jacks, mechanical jacks, hydraulic jacks and heavy air jacks. It is often used when changing tires and checking the condition of the chassis.

Rack jack: The most common type of tool used in household vehicles. Human power drives the rack to lift heavy objects through levers and gears. This type of jack has two shapes, one is "herringbone" and the other is "diamond". The herringbone jack is light in weight and easy to store when folded. The disadvantage is that the supporting weight is small and it is not very strong. It is generally used for a family car of about 1 ton. The principle of the diamond jack is similar to that of the herringbone. Before using it, familiarize yourself with the assembly of the crank handle before using it.

Mechanical jack: The lifting function is realized by the rotation of the thread, and the heavy object is supported by the self-locking function of the thread. This kind of jack has simple structure, is damaged and bears a relatively large weight, has a low transmission efficiency ratio, a slow rise and fall process and a large self-weight, and it is an individual effort to use.

Hydraulic jack: The jack that uses oil pressure to lift is more time-saving and labor-saving. The principle is to manually press the oil in the oil storage cavity into the oil cylinder through a one-way valve to lift heavy objects. This jack lifts and lowers quickly, and can withstand a weight of about 3 tons. It can be seen by car repair shops, but it is large and inconvenient to carry. Although it is easy to use, it must also consider the space and beauty of the car. Degree, so basically no car will be equipped with such a behemoth.

Inflatable jack: This kind of jack is still rare at present, and it is basically a separately purchased tool. Inflatable jacks are suitable for more special environments, such as self-rescue and relief of off-road vehicles, and rescue in difficult road conditions. Its principle is to connect the exhaust pipe of the automobile through the rubber pipe, and use the exhaust gas of the automobile to inflate the air bag to achieve the supporting effect. The air bag is very tough and can withstand a weight of about 4 tons, and because it is not restricted by road conditions, it saves the trouble of finding a flat ground and can be used at any time.

Notes for use

1. Before repairing the car, first fix the car to avoid damage to the car and people due to the slipping of the car during the lifting process. It is not enough to use the handbrake for a fixed vehicle. The safest way is to pull up the handbrake and put the manual transmission model into 1st gear or reverse gear at the same time. For the automatic transmission model, pull the handbrake and push the gear to P gear.

2. The jack must be placed on a hard and flat ground. If the car is accidentally broken on the soft ground or sand, you can use a hard wooden board to point under the jack to ensure the support angle of the jack. Different environments have different methods. , But we must ensure that the jack is secure. In addition, the spare tire can be placed on the chassis. If the jack unfortunately "died", the spare tire can be "underground".

3. The inside of the side skirts of each car has the support points of the jack parallel to the side skirts, which can be touched by hand, so when using the jack, it must be supported on a dedicated support point. The support point is made of steel plate. Big. Other parts, such as the lower guard plate of the engine and the suspended lower arm, must avoid the support of the jack. Due to its low strength, it is easy to cause unnecessary damage when slipping occurs.

4. Hand crank is usually used when using a jack.