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In order to understand the safety status of traction drive elevator brake, taking the most common drum brake as the research object, several common failure forms of drum brake and the problems found in brake disassembly are summarized and sorted out. Based on the analysis of failure causes, suggestions on the use and maintenance of elevator brakes are put forward, and the in-service elevator brakes which have been used for a certain period of time are tested, and the performance characteristics of the in-service elevator brakes are analyzed, which provides a basis for the promotion of hidden trouble investigation and rectification of elevator brakes.

The particle emission characteristics of a drum brake under different braking cycles and braking conditions are studied based on the inertia test bench, brake sealing chamber, and particle test equipment. The results show that a large number of particles are generated during the braking process, and the number of solid particles at a nominal particle size of approximately 10 nm electrical mobility diameter and larger (SPN 10 ) emission factor can reach 8.927×10 9 #/km under different braking cycles. With the increase of initial braking speed, initial braking temperature, and vehicle load, the brake wear particulate generated in the braking process increases. The total brake wear particulate number emission has a quadratic function relationship with the initial braking speed and a linear relationship with the initial braking temperature. Brake deceleration has little effect on total brake wear particulate number emissions produced in one brake process.

Vehicles need to brake frequently on long downhill sections. In this case, the surface of the friction lining is prone to accumulating a large amount of heat, which will reduce the performance of the braking material and lead to braking failure. This article analyzes the heat generation and dissipation mechanism during the braking process of drum brakes based on the law of energy conservation, and establishes a thermal conductivity differential equation. Subsequently, with the honeycomb texture as the biomimetic target, circular, square, and honeycomb patterns with different parameters were designed on the surface of the friction lining, and a finite element model was established using Ansys Workbench. Thermodynamic coupling analysis shows that patterned friction lining can reduce the maximum temperature of the braking surface. Honeycomb patterns have better heat dissipation effects than circular and square patterns. Compared with non patterned brake pads, honeycomb patterns can reduce the maximum surface temperature of brake pads by 14.6%. When the surface area ratio of the honeycomb is 56.8%, its heat dissipation effect is the best.

Both drum brakes and disc brakes have their own structural limitations and advantages. As a new type of industrial brake, cone brake combines the advantages of electric hydraulic drum brake and electric hydraulic disc brake, makes up for the shortcomings of drum brake and disc brake, and greatly improves the service performance and safety performance of the brake. This paper introduces the structure composition and working principle of the conical surface brake, analyzes the advantages of the conical surface brake through the comparison with the drum brake, carries out experimental research, analyzes the test results, gives optimization suggestions for the existing shortcomings, and explores the application prospect of the new brake combined with the introduction of application examples. This paper provides a reference for the technical innovation of brake and a new choice for brake users.

In order to reduce the influence of random parameters uncertainty on the safety performance of the vehicles, the Reliability-Based Robust Optimization Design (RBROD) is conducted on a drum brake under multiple failure modes, and a more effective and accurate method is found for the braking system robust design. The design of experiment method is used to obtain the 400 sample data sets between the design parameters and the natural frequency of drum brake, and the accuracy of the established model is verified by experiment. Taking the brake’s weight and the Euclidean norm of the reliability sensitivity as optimization objectives, and the range of design parameters and system reliability as constraints, the RBROD mathematical model is established. RBROD is conducted by four meta-model methods, and the results are verified by finite element analysis. The research results show that the drum brake after RBROD meets the requirements of reliability, robustness, and optimization design, and the adaptive Kriging method has the highest calculation accuracy and efficiency among the four meta-model methods.

In this study, the fatigue usage factors for Findley and Matake stress-based criteria were determined in the case of an MK5×2 mine hoist drum brake system subjected to cyclic maneuver braking. The study was conducted for this type of brake system, because the majority of mine hoists in Romanian mines are equipped with this brake type, being in operation for several decades. A geometric model of the brake was built using SolidWorks and imported in COMSOL Multiphysics to perform thermo-mechanical simulations. Based on the deformations and von Mises stresses determined by the thermomechanical simulation and, considering the calculated endurance limits of the brake system materials, Matake and Findley fatigue life evaluation simulations from COMSOL’s fatigue module were conducted. The results show that the highest fatigue is expected on the drum lining surface towards the exit point from under the brake shoe in both cases, and the values of the usage factor of 0.307 (Findley) and 0.401 (Matake) are both under the critical value 1, meaning that the stress limit has not been exceeded for the brake system components and, thus, failure is not expected. Simulations were conducted considering an estimated 1.06 × 105 cycles during one year, more than both the usual service/replacement interval of the friction components of the brake, and the period of mandatory technical inspections imposed by regulations.

In order to meet the demand of turning over brakes in an automatic assembly line of drum brakes, a drum brake turnover machine is designed. SolidWorks software is used to complete the three-dimensional modeling of the mechanical structure of the whole device; The control system of the drum brake turnover machine based on Schneider M241 PLC is designed, and the AC servo system control based on CANopen BUS is realized. The precise control of the position of reclaiming, overturning, discharging and turning angle of the drum brake is achieved. The engineering application results show that the equipment has a high degree of automation, stable operation, and good economy.

Exhaust regulations and improved exhaust gas treatment systems have already initiated the trend that brings emissions from brakes and tires to the forefront of traffic-induced particulate matter. The health and environmental relevance of particulate matter has resulted in regulators, industry, and research institutions prioritising the mitigation of non-exhaust particle emissions. To this end, under the umbrella of the United Nations Economic Commission for Europe World Forum for Harmonisation of Vehicle Regulations (UNECE WP.29), the Working Party on Pollution and Energy (GRPE) mandated the Particle Measurement Programme Informal Working Group (PMP-IWG) to develop a Global Technical Regulation (GTR) for measuring brake dust. The standards and procedures defined within the GTR should eventually form the basis for the introduction of a Euro 7 limit value for brake emissions. The purpose of this measurement campaign is to provide an exemplary overview of the emission behaviour of wheel brakes and friction pairings currently available on the market and to identify possible reduction potential with regard to particulate emissions. All measurements were carried out taking into account the draft GTR valid at the time of execution. For the investigations, brakes were selected using the example of different vehicle classes, brake concepts (disc and drum brake), vehicle axles (front and rear axle), and alternative friction materials (brake disc and pads/shoes). Thus, the use of wear-resistant discs and improved brake pad compositions are able to achieve significantly lower emissions. In addition, the measurement of brake dust emissions from vehicles with different levels of electrification was considered. Electrical braking was modelled and applied to the Worldwide Harmonised Light-Duty Vehicles Test Procedure (WLTP) Brake Cycle, which has demonstrated high emission reduction potentials depending on the electrification level.

Passenger safety is of utmost importance in the automotive industry. Hence, the health of the components, especially the brake system, should be effectively monitored. On account of the significance of artificial intelligence in recent times, any brake fault resulting during operation can be accurately detected using a combination of advanced measurement techniques and machine learning algorithms. The current study focuses on developing and evaluating a robust framework to quantify and classify the faults of a general automotive drum brake. For this purpose, a new experiment for a drum brake, which can be operated under a controlled environment with known levels of faults, is developed. The experiment is instrumented to measure the fundamental dynamic signals (such as brake torque, the angular velocity of the brake drum, and brake shoe accelerations) during a braking event. The response signals from several experiments with various faults and operating conditions serve as the input dataset for establishing the fault quantification algorithm. Multiple variants of this algorithm are devised using different subsets of the input dataset. The selection of features in each variant is done through sensitivity-based segregation with the help of artificial neural networks. The performance of all the variants is comparatively evaluated, and the best among them is determined based on the fault quantification error. Finally, fault classification is carried out using the best variant after establishing the classification thresholds based on the confusion matrix. The following are the novel aspects of this work: (i) design and development of a laboratory experiment for drum brakes that can imitate a real-life braking condition; (ii) measurement of the dynamic response of the system during a typical braking event with a controlled type and level of brake fault using appropriate instrumentation; (iii) estimation of the magnitude of multiple brake faults, in addition to their classification; and (iv) identification of the critical vibration measurements necessary for detecting faults in brakes. In addition, the physical insights into the brake system response, selected features, and the fault quantification algorithm are presented. The proposed framework can also be implemented for fault diagnosis in different automotive subsystems by using an equivalent experiment. The goal of the current work is to develop a simple in situ tool for monitoring the health and diagnosing faults in automotive drum brakes. When integrated with other smart diagnostic and prognostic features, this tool can help automotive manufacturers improve passenger safety.

When a truck makes emergency braking while driving on a slope, the transient impact force generated can easily cause personal injury to passengers and damage the vehicle’s braking system. In order to study the working state of the brake under this working condition, the ANSYS finite element thermal-solid coupling transient analysis method was used to establish the mechanical model and finite element model of the vehicle and brake under the slope emergency braking state, showing the temperature field and stress field distribution rules and interactions of the drum brake under this working condition, and compared with the flat road emergency braking condition. The results show that the maximum temperature of the brake reaches 184.26°C during emergency braking, and the stress field and temperature field are strongly coupled in two directions, which can easily lead to uneven wear of the linings and a reduction in the fatigue life of the brake.