各双回路制动系统在某回路失效时的制动能力分析

现代轿车大多采用双回路制动系统,以保证某一回路失效后汽车仍有一定的制动能力。对各种型式的前后轮制动器制动力具有固定比值分配的双回路制动系统在某一回路失效时的用来分析制动能力的各公式进行了推导,发现回路失效后,其I曲线f、线组r、线组、同步附着系数、制动效率、利用附着系数都与失效前不同。

Coupling vibration analysis of high-speed maglev train-viaduct systems with control loop failure

The risk of failure of the control loop can occur when a high-speed maglev train runs on viaduct.Meanwhile,the failure of the levitation magnets which balances the gravity of the maglev train could cause the train collision with track.To study the dynamic response of the train and the viaduct when the levitation magnet control loop failure occurs,a high-speed maglev train-viaduct coupling model,which includes a maglev controller fitted by measured force-gap data and considers the actual structure of train and viaduct,is established.Then the accuracy and effectiveness of the established approach are validated by comparing the computed dynamic responses and frequencies with the measurement results.After that,the dynamic responses of maglev train and viaduct are discussed under normal operation and control loop failures,and the most disadvantageous combination of control loop failures is obtained.The results show that when a single control loop fails,it only has a great influence on the failed electromagnet,and the maglev response of adjacent electromagnets has no obvious change and no collision occurs.But there is a risk of rail collisions when the dual control loop fails.

一则中性按钮粘连引发的电梯电气控制缺陷案例的分析

介绍了一则由电梯检修中性按钮粘连引发的电梯电气控制缺陷案例。结合该电梯的安全回路、检修电气控制回路对该缺陷产生的原因进行了分析,提出相应的整改建议。最后针对该案例反映的问题,指出了检验中应注意的事项。