DEVELOPMENT OF METHODS FOR DETECTING AND PREVENTING FAULTS IN THE BRAKING SYSTEM OF CARS

ABSTRACT

This article lists the most common failures in the brake systems of cars produced by UzAuto Motors, identifies the causes and develops solutions.

АННОТАЦИЯ

В данной статье перечислены наиболее частые отказы тормозных систем автомобилей производства UzAuto Motors, определены причины и разработаны решения.

Keywords: car, brake system, active safety, traffic accident, reliability, fault, malfunction, tire, wheel mounting angles, resource.

Ключевые слова: автомобиль, тормозная система, активная безопасность, дорожно-транспортное происшествие, надежность, неисправность, неисправность, шина, углы крепления колес, ресурс.

INTRODUCTION

It is impossible to create the basis of a developed society without modern transport, which is highly developed. Because transport is an integral part of any productive force. The role of road transport in the transportation of goods in the national economy and agriculture is enormous. Vehicles play an important role in the transportation of natural resources, internal and external cargo turnover of the economy, etc. In addition, transport plays an important role in the rational use of labor resources, increasing the state's defense capabilities.

The number of cars on the country's roads continues to grow steadily. Modern cars have very high dynamic properties, making them high-hazard objects. Despite the measures taken by the state to improve road safety, the number of road accidents is not decreasing.

Automobile plants and engineering companies are constantly improving the design of vehicles and, above all, improving their safety. Much attention is paid to improving the braking control system of the vehicle as a means of creating active safety.

Thus, due to the increase in energy intensity of cars and the increase in the number of cars, the increase in braking in cars leads to an increase in the demand for car brakes, both in the design of brakes and in the use of materials.

METHOD

Based on the above, the development of scientific and practical research and innovation on constantly produced cars is a requirement of the times.

In order for our cars manufactured in our country to have a place in the world market, their design and operational reliability must meet international standards.

  During the use of UzAuto Motors in our country, that is, during its operation, there are operational failures in cars, especially in the brake system of cars.

RESULT

The reliability of the brake system is of great importance during the operation of vehicles. Therefore, it is necessary to ensure the reliability of the brake system of domestic cars during operation. Faults in this system can reduce the safety of passengers in the car. This can lead to adverse events. In order to prevent such incidents, it is necessary to identify, study and eliminate faults in the brake system.

External factors affecting the operation of the brake system.

Tires

The brakes of the tires that make different contacts and adhesions on the road are different. Therefore, it is recommended that the tire pressure be kept within the normal range. The tread depth and shape of the tires on the same axle should be approximately the same.

Car loading

If the car is not loaded evenly, more braking torque is required than other wheels to brake the heavier wheels. To brake a fully loaded vehicle, you need to apply the brakes with great force.

Wheel mounting angles.

Violation of the mounting angles will cause the vehicle to pull sideways when braking.

Fault information. Damage to the car and loss of performance can affect its reliability. In the event of a malfunction, the vehicle will lose all or part of its ability to operate and will not be able to perform the specified number of transport operations. Reliability is determined by the parameters that determine the performance of the car over time. Considering the performance of the car or its components from the point of view of reliability, the following factors can be distinguished: the average work performed before failure, the time of recovery after failure, the distance traveled to the final state, a certain distance the number of failures from the time they are accounted for until they are written off. For non-repairable elements of the car, the first failure is the last failure, and the condition of the element is the last. Factors affecting the reliability of the car are very diverse and multifaceted, such as different processes or climatic conditions of use during the production of the car, operating mode, quality of fuels and lubricants, quality of maintenance, we can say that the above parameters are random variables at the expense of driving skills and so on. The reliability of a car as a whole is equal to the sum of the reliability of its components and parts. That is, the reliability of the car as a whole or in individual units and parts can be assessed. There are a number of ways to determine the reliability of a vehicle, including: theoretical calculations, experiments, and experimental determinations. The reliability of cars should be calculated on the basis of probability theory and the general laws of mathematical statistics, based on the observation of cars in operation, the collection and processing of data on defects, repairs. In addition to the average value of the indicator, the distribution laws and the confidence limits must be determined for a given probability. A failure is a condition in which a vehicle meets the performance requirements, but does not meet the secondary technical requirements. Examples of faults include headlight breakage and body crush. [1]

DISCUASSION

In general, the causes of disorders can be divided into three types:

• constructive, ie the imperfect structure of the car, its units and mechanisms, the inadequacy of the materials selected at the time of design, and so on;
• technological deficiencies in the technology of production of the car or its parts, errors and the like;
• poor quality or untimely maintenance of the vehicle during operation, ie bad climate and road conditions.

This means that the quality of the car depends mainly on its high reliability, and reliability is ensured during the design and production processes. In order to increase the reliability of the car, it is necessary to pay attention to the design factors that affect it during design. It is known that 80-85% of car breakdowns are caused by wear and tear of parts due to friction. Therefore, during the design phase, great attention should be paid to the conversion of slippery friction into rolling friction, reducing the load on the friction surface, protecting the surfaces of the friction pairs from contaminants, and compensating for wear. the rate of slippage and pressure on the surfaces of friction pairs varies widely over time. [2]

In addition, the following brake failures are observed during the operation of Uz Auto Motors:

• Weakness of the brakes,
• the wheels are not free of braking or do not turn,
• The brakes on the same axle do not work the same
• air intake and brake fluid leakage into the hydraulic drive system,

Weakening of the brakes is observed when the brake mechanisms and drive adjustments are broken, the brake pads are dirty or lubricated, air enters the drive system, and the volume of brake fluid is reduced. Decreased braking efficiency in vehicles with a hydraulic booster can also be caused by the booster not working properly.

The main reasons why the wheels are not free from braking are the fact that the brake mechanism parts increase their volume due to heat due to excessive braking and the friction surfaces stick to each other.

Uneven brakes on the wheels can cause the car to slip sideways during braking. This condition is often caused by a misalignment of the brakes, as well as the reasons given above.

When air enters the hydraulic drive system, the braking efficiency decreases. This is especially true when the brake pedal is depressed. In this case, you have to press the pedal several times for better braking. If the brake fluid leaks from the system due to a leak, the brake system will fail or one of the circuits will fail in two-stroke drives.

According to scientific researches of domestic and foreign scientists, 80-85% of car breakdowns are caused by friction and wear of parts.

An analysis of the problem situation in Central Asia shows that the service life of vehicles operating in high temperature and dusty conditions is very short, and their reliability and performance are low. In particular, road and climatic conditions have the greatest impact on brake system details. [3]

CONCLUSION

Uzbekistan has a hot climate. The geographical location, relief, natural-climatic and hydrogeological conditions of the territory of Uzbekistan are different and unique.

High temperatures and solar radiation have a significant negative impact on the performance and service life of rubber and plastic parts. Plastic parts lose their shape and material properties. High levels of dust in the air can lead to rapid wear of brake parts.

Having thoroughly studied the topic of the dissertation, based on the road climate in Central Asia, the following recommendations were developed to improve the performance of the brake system of Cobalt cars:

• Due to the hot, dusty climate of Central Asia, the parts of the car brake system are made of materials resistant to abrasive particles;
• In hot climates, the brakes of cars should be well protected, mainly from dust;
• Due to the hot and dry climate, the brake parts of cars should be made of heat-resistant rubber;
• Brake fluids should not evaporate or change their properties as a result of heat in hot climates;
• Lubricant parts must be well sealed;
• Brake parts must not change their size under the influence of heat and must be made of materials that dissipate heat well;
• In addition, given that most of the cars produced by UzAutoMotors are exported to Russia, due to high humidity in Russia, not only the brake system parts, but all car parts must be made of corrosion-resistant materials;

 The latest active safety systems in cars should be used to increase the safety of these cars:

As a result of the study of the topic, the main technological measures to increase the strength and durability of the brake system were included:

• Production of corrosion-resistant materials for various operating conditions of car brakes and production of high-quality semi-finished products close to the finished parts in terms of size;
• Development of technological methods that allow to produce parts that are stable in a given accuracy and size, as well as physical and mechanical properties;
• The use of quality control methods for materials, blanks and finished products that meet the relevant indicators of reliability;

 The use of reinforcing machining processes (high-frequency current, semintitating, cyanidation, chromium plating, etc.) that ensure the required quality of the working surface of brake system parts with high resistance to corrosion and breakage in different operating conditions.

In addition, the causes of the disorder in general are divided into three types:

• constructive, ie the imperfect structure of the car, its units and mechanisms, the inadequacy of the materials selected at the time of design, and so on;
• technological deficiencies in the technology of production of the car or its parts, errors and the like;
• poor quality or untimely maintenance of the vehicle during operation, ie bad climate and road conditions.

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