将PK进行到底:The Ultimate 碟刹和鼓刹 Comparison

“A drum brake is a brake in which the friction is caused by a set of shoes or pads that press against the inner surface of a rotating drum. The drum is connected to a rotating wheel.”



“The disc brake is a device for slowing or stopping the rotation of a wheel. A brake disc (or rotor in U.S. English), usually made of cast iron or ceramic, is connected to the wheel or the axle. To stop the wheel, friction material in the form of brake pads (mounted in a device called a brake caliper) is forced mechanically, hydraulically, pneumatically or electromagnetically against both sides of the disc. Friction causes the disc and attached wheel to slow or stop.”






The drum brake was invented in 1902 by Louis Renault, and the disc brake was patented by Frederick William Lanchester in his Birmingham factory in 1902 but it was adopted a half century later after the first creation.

The one big advantage of the drum brakes is that they are more cost effective than the disc brakes. However, the major flaw is that the drum brakes would often fade and lose effectiveness as the result of too much heat build-up within the drum itself.

On the other hand, disc brakes can dissipate heat quickly than the drum brakes due to the “rotors and pads are open and the rotors have large internal ventilation air passages.”

Therefore, disc brakes can increase the longevity of the tires and can keep the tires in contact with the road more effectively.
Moreover, disc brakes last four times longer than drums and are more effective in decreasing the stopping distances since their brake weight is less.

Therefore cars with four-wheel disc brakes are more effective. However, the majority of the new cars today still utilize a front-disc/rear-drum brake setup. Nevertheless, the current technology on rear drum brake systems has also been significantly improved since the last few decades. In conclusion, with today’s technology a vehicle’s majority stopping power comes from the front wheels and thus “a well-designed, modern drum brake is all that’s required for most rear wheel brake duty.”

注: 由于大家对碟刹和鼓刹的重视,也驱使了我的好奇心整理了这么1篇.
大致上跟ifidonlike和CHN俩位大侠的差不多.
所有的CREDIT都归于原创者.

References:
http://en.wikipedia.org/wiki/Drum_brake
http://en.wikipedia.org/wiki/Disc_brake
http://www.edmunds.com/ownership/techcenter/articles/43857/article.html