With the continuous improvement of logistics transportation efficiency, the speed of trailer transportation is also increasing, especially for medium and long-distance transportation, the speed of more than 70 per hour is common. However, when the vehicle is fully loaded, dozens of tons of behemoths fly at high speed. In case of an accident, the results are often shocking, and the bumpers, seat belts and airbags seem to be inadequate. In order to better protect the safety of trailer owners and traffic participants, more and more safety devices have been born.

These safety devices also have the difference between active and passive.

In short, active safety devices refer to safety devices that can prevent accidents. The main goal is to prevent accidents in the first place, focus on monitoring and prediction, and avoid accidents through a series of vehicle control means. Passive safety devices focus on reducing accident injuries. After a vehicle accident, a series of measures are taken to reduce the injury of passengers when the vehicle is out of control.

Common passive safety devices on trailers:

1. Safety body. It can be divided into "soft protection" and "hard protection". "Soft protection" is to absorb most of the impact of external forces through preset permanent deformation of folds; "Hard protection" mostly adopts high-strength materials and solid body structure design to reduce the deformation of the body in case of vehicle accidents.

2. Safety glass. It is generally divided into tempered glass and laminated glass. When the toughened glass is broken, it is divided into many small pieces without sharp edges, which is not easy to hurt people; There are three layers of laminated glass. The middle layer has strong toughness and adhesion. When it is damaged by impact, the inner layer and outer layer still adhere to the middle layer, which can reduce the injury risk of glass fragmentation.

3. Seat belts. This is the most common. Needless to say, fasten your seat belt on the bus. This is the most basic car specification.

4. Seat head and neck protection: for example, whips head and neck protection system is not widely used in trailers at present. Its principle is that in case of vehicle impact, the seat head and neck position will inflate and expand rapidly, and the seat back and headrest will translate backward, so as to reduce the impact force.

5. Airbag. This is the last passive safety defense line, which is set in front and side of the cab, which can reduce the secondary collision injury caused by inertia.

6. Tire burst emergency device. At present, this technology is rarely used in trailers. Its principle is to install a simple "track" in the hub groove to fill the difference in the inner diameter of the rim when the tire burst, so as to avoid the tire from being drawn into the groove bottom or separated from the rim after the tire burst or pressure loss. It can also use the rubber thickness support of the pressure loss tire to form a rubber pad to ensure the continuous control of the vehicle.

Common active safety devices on trailers:

1. Body electronic stability system. For example, esp, ESC, DSC, TCS, VSA and other names are all body electronic stability systems, but there are differences in manufacturers, technologies and functions. Its main function is to stabilize the running track and ensure the balance of the vehicle body by controlling the movement of the driving wheel and the driven wheel when the vehicle runs to the road section with poor road conditions.

2. Anti collision early warning system. Mainly analyze the conditions of the lane and surrounding vehicles through the probe or radar, and give active early warning in time when the distance is too close.

3. Lane departure warning system. It can automatically plan the forward direction according to the information of the camera. When the vehicle travels abnormally or changes lanes without turning on the turn signal, it will trigger the lane departure warning.

4. DMS driver monitoring system. The main function is to monitor the driver's facial information. When the driver is distracted, playing with his mobile phone, tired or dozing, he will immediately call the police to remind the owner to pay attention.

5. ABS anti lock braking system. In case of emergency braking during vehicle driving, it is easy to cause wheel locking. After installing ABS, it can prevent wheel locking, simulate the state of "spot braking", and improve the maneuverability and stability of the vehicle during emergency braking and the braking performance of the vehicle under poor road conditions.

6. EBS electric brake system. It is upgraded from the ABS system. Using electronic instead of traditional mechanical transmission to control the braking system can fully improve the reaction speed of the braking system. According to gb7258-2017, dangerous goods transport vehicles with total mass ≥ 12000kg must be equipped with electric braking system from January 1, 2021.

7. ASR drive anti slip system. When the driving wheel slips when the vehicle starts, it can be used to stabilize the vehicle body, maintain the directional stability of the vehicle when driving, and make use of the longitudinal adhesion between the wheel and the road as much as possible to provide the maximum driving force.

8. AEB automatic emergency braking device. It can be regarded as the "extension" of the anti-collision early warning system. The radar is used to measure the distance from the front vehicle or obstacles, analyze the data, and compare it with the alarm distance and emergency braking distance. If it is ≤ the alarm distance, the anti-collision early warning will be carried out. If it is < the safe distance and the owner does not do anything, the automatic braking will be started.

9. Tire pressure monitoring system. Also known as TPMS, it obtains tire pressure data through the electronic pressure sensor installed in the tire, wirelessly receives and displays, and monitors tire pressure in real time. When the air pressure is too low, too high and rapid air leakage, the alarm will be given in time. At the same time, the tire pressure monitoring will keep the standard pressure at all times, which will help reduce the fuel consumption of the vehicle and prolong the service life of the tire.

In addition, there are many other safety devices, such as team holding system, lane change assist system, seat vibration system, active cruise and so on. Although there are many kinds of safety devices, the most basic and important "safety device" is a good and cautious driving habit, otherwise no matter how intelligent or high-end safety devices can absolutely guarantee personal safety.

It is worth noting that many safety devices related to trailer braking system, such as ABS and EBS system, can greatly improve the response efficiency of vehicle braking, but if they want to give full play to their maximum use effect, they also need to be matched with braking devices with rapid response and stable performance. From this level, disc brake is better than drum brake. For example, the disc axle produced by Darong group reduces the number of parts in the braking reaction process, and directly uses the wheel cylinder to push the caliper, which has faster response speed, more timely braking and more stable braking force output. With faster reaction efficiency, it is matched with ABS and EBS systems to make the vehicle stop smoothly in the shortest distance. Therefore, the use of disc axle and air suspension is also a safety guarantee, but heavy transport trailers also need to be equipped with hydraulic retarders.