发动机功率的提高,使得现代商用汽车的行驶速度提高到了接近中级轿车的速度水平,但是,当遇到紧急情况需要制动时,这些车辆就处于不利的地位。与其他车辆相比,由于其自身的质量较大,制动起来比较困难,这就对原有的制动系统提出了挑战。在高速公路上紧急制动时,老式的鼓式制动器 The increase in engine power has allowed modern commercial vehicles to reach speeds approaching those of mid-size sedans, but these vehicles are at a disadvantage when braking in an emergency. Compared with other vehicles, due to its own larger mass, braking more difficult, which posed a challenge to the original brake system. Vintage drum brake on emergency brake on the highway