外文翻译--盘式制动器

附录 A Disc Brakes Disc brakes are used on the front wheels of most cars and on all four wheels on many cars. A disc rotor is attached to the wheel hub and rotates with the tire and wheel. When the driver applies the brakes, hydraulic pressure from the master cylinder is used to push friction linings against the rotor to stop it. In the disc brake rotor assembly, the rotor is usually made of cast iron. The hub may be manufactured as one piece with the rotor or in two parts. The rotor has a machined braking surface on each face. A splash shield, mounted to the steering knuckle, protects the rotor from road splash. A rotor may be solid or ventilated. Ventilated designs have cooling fins cast between the braking surfaces. This construction considerably increases the cooling area of the rotor casting. Also, when the wheel is in motion, the rotation of these fan-type fins in the rotor provides increased air circulation and more efficient cooling of the brake. Disc brakes do not fade even after rapid, hard brake applications because of the rapid cooling of the rotor. The hydraulic and friction components are housed in a caliper assembly. The caliper assembly straddles the outside diameter of the hub and rotor assembly. When the brakes are applied, the pressure of the pistons is exerted through the shoes in a clamping action on the rotor. Because equal opposed hydraulic pressures are applied to both faces of the rotor throughout application, no distortion of the rotor occurs, regardless of the severity or duration of application. There are many variations of caliper designs, but they can all be grouped into two main categories: moving and stationary caliper. The caliper is fixed in one position on the stationary design. In the moving design, the caliper moves in relation to the rotor. Most late-model cars use the moving caliper design. This design uses a single hydraulic piston and a caliper that can float or slide during application. Floating designs float or move on pins or bolts. In sliding designs, the caliper sideways on machined surfaces. Both designs work in basically the same way. In the single piston floating caliper, the single-piston caliper assembly is constructed from a single casting that contains one large piston bore in the inboard section of the casting. Inboard refers to the side of the casting nearest the center line of the car when the caliper is mounted. A fluid inlet hole and bleeder valve hole are machined into the inboard section of the caliper and connect directly to the piston bore. The caliper cylinder bore contains a piston and seal. The seal has a rectangular cross section. It is located in a groove that is machined in the cylinder bore. The seal fits around the outside diameter of the piston and provides a hydraulic seal between the piston and the cylinder wall. The rectangular seal provides automatic adjustment of clearance between the rotor and shoe and linings following each application. When the brakes are applied, the caliper seal is deflected by the hydraulic pressure and its inside diameter rides with the piston within the limits of its retention in the cylinder groove. When hydraulic pressure is released, the seal relaxes and returns to its original rectangular shape, retracting the piston into the cylinder enough to provide proper running clearance. As brake linings wear, piston travel tends to exceed the limit of deflection of the seal； the piston therefore slides in the seal to the precise extent necessary to compensate for lining wear. The top of the piston bore is machined to accept a sealing dust boot. The piston in many calipers is steel, precision ground, and nickel chrome plated, giving it a very hard and durable surface. Some manufacturers are using a plastic piston. This is much lighter than steel and provides for a much lighter brake system. The plastic piston insulates well and prevents heat from transferring to the brake fluid. Each caliper contains two shoe and lining assemblies. They are constructed of a stamped metal shoe with the lining riveted or bonded to the shoe and are mounted in the caliper on either side of the rotor. One shoe and lining assembly is called the inboard lining because it fits nearest to the center line of the car. The other is called the outboard shoe and lining assembly. As already mentioned, the caliper is free to float on its two mounting pins or bolts. Teflon sleeves in the caliper allow it to move easily on the pins. During application of the brakes, the fluid pressure behind the piston increases. Pressure is exerted equally against the bottom of the piston and the bottom of the cylinder bore. The pressure applied to the piston is transmitted to the inboard shoe and lining, forcing the lining against the inboard rotor surface. The pressure applied to the bottom of the cylinder bore forces the caliper to move on the mounting bolts toward the inboard side, or toward the air. Because the caliper is one piece, this movement causes the outboard section of the caliper to apply pressure against the back of the outboard shoe and lining assembly, forcing the lining against the outboard rotor surface. As the line pressure builds up, the shoe and lining assemblies are pressed against the rotor surfaces with increased force, bringing the car to a stop. The application and release of the brake pressure actually causes a very slight movement of the piston and caliper. Upon release of the braking effort, the piston and caliper merely relax into a released position. In the released position, the shoes do not retract very far from the rotor surfaces. 附录 B 外文翻译： 盘式制动器 许多汽车所有四个车轮 ， 盘式制动器是用 在 大多数轿车的前轮上。 制动盘安装在轮毂上随着轮胎和车轮转动。 当 汽车制动时 ，液压主缸推动摩擦片 使其 停止转动 。 在盘式制动器 的 转 动部件中 ， 制动盘 通常是 使用 铸铁 制造 。 轮毂和制动盘 可制造为一体或两部分。 制动盘 的每个面 都要 加工 为 制动 表 面。一 块防护板 ，安装在转向节 上 ，保护 制动盘不被飞溅物污染 。 制动盘 可以是 实心 或 有 通风 孔 。 拥 有通风 孔的制动盘表面之间设有散热片 。这种结构大大提高了 制动盘的 散热 面积。此外，当车轮在运动时，这些风扇型 散热片 在 制动盘 旋转 时 增 大 空气流通 并 提供更有效的 制动 冷却。盘式制动器不 会受热变形 ，即使快速 、强制制动 ，原因 就 是 制动盘 的快速冷却。 液压和摩擦部件都 安 装在 制动钳总成中 。 制动钳 跨越 轮毂和制动盘 外径。当制动器作用时 ，通过活塞 推动制动块 在夹紧 制动盘 的 过程中产生 压力。由于 在制动过程中液 压 压力 等于应用于 制动盘两侧 ， 制动盘 没有出现 变形 ，无论 过程的压力多大和持续时间 。也有许多 种制动钳 ，但他们都可以分为两大类：移动和固定卡钳。 固定式 卡 钳 是固定在一个固定的设计位置上。在移动 式设计中 ， 制动 卡钳相对于制动盘 移动。 大多数晚期 制造的汽车 使用移动 式卡钳 。 在 设计 中 采用一个 单独的 液压活塞和能够在制动过程中滑动或摆动的卡钳 。 在滑动设计中卡钳 在 导向销上 移动。在摆动式 设计 中 ， 卡钳在垂直表面内摆动 。这两种设计的工作方式基本相同。 在单活塞浮动卡钳 中 ，单活塞卡钳大 多 是 由 一个单一的铸 件构成 ，其中包含一个大 型 钻孔 作为 铸件的内侧部分。内侧是指卡钳安装 时 靠近汽车铸 件 的一面。制动液 入口孔和 排气 孔的加工成的卡钳内侧部分，直接连接到活塞孔。 制动钳 缸包含一个活塞和密封 圈 。该密封 圈 具有矩形截面。它坐 落在一个在缸 体的 加工孔槽。适合的密封活塞周围的外径，并提供了活塞与缸壁液压密封件