| 摘要 |
<p>A disc brake rotor (10) provides two oppositely-facing annular friction surfaces (16, 18) which, in the operation of the brake, are engaged by blocks of friction material to decelerate the rotor. The rotor (10) comprises a first portion (12) which provides one of the friction surfaces (16) and a second portion (14) which provides the other (18). Said first and second portions (12, 14) are arranged in spaced parallel relationship and are joined by vanes (26) between which are defined cooling ducts (28). The rotor (10) also comprises air inlet ports (34, 36) passing through said first and said second portions (12, 14) in areas which are radially inward of said vanes (26). In order to reduce vibration, the number of inlet ports (34) which pass through the first portion (12) of the rotor (10) is different to the number of inlet ports (36) which pass through said second portion (14).</p> |
