【正文】 lic system pressure. VALVING Valves monly found in hydraulic brake systems include: Proportioning, or pressurebalance valves. These restrict a percentage of hydraulic pressure to the rear brakes when system pressure reaches a preset high value. This improves front/rear brake balance during highspeed braking, when some of a vehicle39。 ? Ease of locating leaks, since fluid is visible. There are many more permutations of hydraulic brake systems than found in air systems, but all have basic similarities. THE HYDRAULIC SYSTEM All hydraulic brake systems contain a fluid reservoir, a master cylinder, which produces hydraulic pressure, hydraulic lines and hoses to carry pressurized fluid to the brakes, and one or more wheel cylinder(s) on each wheel. The wheel cylinders expand under fluid pressure, and force the brake shoes against the insides of the drums. If disc brakes are used, calipers, with integral cylinders, clamp down on the rotors when pressure is applied. Because a vehicle must be able to stop much more quickly than it can accelerate, a tremendous amount of braking force is needed. Therefore, the retarding horsepower generated by the brakes must be several times that of the engine. In order to develop the forces required to hold the brake linings against the drums or discs, and to achieve controlled deceleration, it is necessary to multiply the original force applied at the brake pedal. When a hydraulic system is used, the only mechanical leverage is in the foot pedal linkage. However, varying the diameter of the wheel cylinders or caliper diameters, in relation to the master cylinder bore diameter, provides an additional increase in ratio. In a hydraulic system, the pressure delivered by the various wheel cylinders is directly affected by the areas of their pistons. For example, if one wheelcylinder piston has an area of 2 square inches, and another piston has an area of 1 square inch, and the system pressure is 400 psi, the 2squareinch piston will push against the brake shoes with a force of 800 pounds. The 1squareinch piston will exert a force of 400 pounds. The ratio between the areas of the master cylinder and the wheel cylinders determine the multiplication of force at the wheel cylinder pistons. Keep in mind that the larger a wheel cylinder39。s because air and hydraulic brakes each have operating characteristics that make one or the other ideal for certain applications. In heavyduty bination vehicles, air is the clear choice because of the large volume of liquid that would be needed to acadia all the wheel cylinders. Plus, dealing with gladhands and hoses filled with hydraulic fluid would be messy. But for light and mediumduty straighttruck applications, hydraulic brakes offer advantages including: ? Brake feel — that is, as the pedal is pressed farther down, effort increases。結(jié)果是制動(dòng)距離大大增加。此外 碟式剎車比鼓式制動(dòng)器 耐熱褪色性能更好 。鼓或轉(zhuǎn)子較重的是，它可以容納更多的熱量。雖 然一些舊的鼓式制動(dòng)器總成，手動(dòng)調(diào)整，大部分都是自動(dòng)。 鼓式制動(dòng)器說是自激。繼續(xù)轉(zhuǎn)儲(chǔ)閥是脈沖在防抱死模式，以保持車輪轉(zhuǎn)動(dòng)，同時(shí)保持控制的減速。在當(dāng)前的液壓防抱死系統(tǒng)，轉(zhuǎn)儲(chǔ)閥釋放壓力到一個(gè)累加器在即將車輪鎖死的情況下液壓油。 其他泊車系統(tǒng)包括彈簧 腔，像那些用于空氣制動(dòng)系統(tǒng)。這些閥門不來硬制動(dòng)過程中發(fā)揮作用。隨著車輛的負(fù)載增加（降低高度）液壓后輪剎車是不允許的 。 閥桿 液壓制動(dòng)系統(tǒng)中常見的閥門包括： ?配比，或壓力平衡閥門。這有助于踏板的努力，并增加對(duì)制動(dòng)液的壓力，無需過分增加在踏板努力。隨著壓力的一個(gè)電路，其他電路的正常壓力，迫使活塞的失效一邊，關(guān)閉的接觸，并照亮儀表板警示燈。當(dāng)然，不應(yīng)該被驅(qū)動(dòng)的車輛遠(yuǎn)超過必要的制動(dòng)系統(tǒng)修復(fù)。液壓制動(dòng)系統(tǒng)分割的系統(tǒng)，包括兩個(gè)謹(jǐn)慎的制動(dòng)電路。 液壓系統(tǒng)中，各分泵交付的壓力，直接影響由活塞地區(qū)。請(qǐng)記住，直徑較大的輪缸的，更流暢，必須由主缸提供，以填補(bǔ)它。例如，如果一個(gè)輪缸活塞面積 2 平方英寸，另一個(gè)活塞面積 1 平方英寸，系統(tǒng)壓力為 400 磅， 2 平方英寸的活塞將針對(duì) 制動(dòng)器 推一個(gè)迫使800 磅。為了發(fā)展須持有對(duì)鼓或盤制動(dòng)器襯片的力量，實(shí)現(xiàn)受控減速，這是要乘原始的力量施加在剎車踏板。 分泵 擴(kuò)大流體壓力下，迫使制動(dòng)蹄對(duì)鼓的內(nèi)側(cè)。 ?衛(wèi)生 ， 液壓制動(dòng)器是封閉的系統(tǒng) 。此外，充滿液壓油與 制動(dòng)分泵 和 軟 管的將是混亂的。 杭 州 電 子 科技大學(xué) 畢 業(yè) 設(shè) 計(jì)（ 論 文 ） 外 文 文 獻(xiàn) 翻 譯 畢業(yè)設(shè)計(jì)（論文）題目 翻譯 （ 1） 題目 液壓制動(dòng) 器 基礎(chǔ) 翻譯（ 2）題目 有用的產(chǎn)品 學(xué) 院 機(jī)械學(xué)院 專 業(yè) 車輛工程 姓 名 班 級(jí) 學(xué) 號(hào) 指導(dǎo)教師 液壓制動(dòng)基礎(chǔ) 空氣制動(dòng)系統(tǒng)得到更多的關(guān)注，但更多的車輛上安裝液壓制動(dòng)器。重型組合的車輛，空氣是明確的選擇，因?yàn)閷⑿枰罅康囊后w阿卡迪亞所有分泵。 ?更少的初始費(fèi)用，由于 用 更小和更少的元件 。 液壓系統(tǒng) 所有的液壓制動(dòng)系統(tǒng)包含流體水庫，主缸，液壓，液壓管路， 對(duì)制動(dòng)器 進(jìn)行加壓流體 的軟管 和一個(gè)或多個(gè)輪缸（ S）對(duì)每個(gè)車輪產(chǎn)生。因此，必須減速剎車產(chǎn)生的馬力的發(fā)動(dòng)機(jī) 作用 多次。液壓系統(tǒng)中，各分泵交付的壓力，直接 影響由活塞地區(qū)。為 保持在頭腦，直徑較大的輪缸的，更流暢，必須提供由主缸行程較長(zhǎng)的碩士轉(zhuǎn)化。顯然，必須更換主缸，輪缸或卡尺相同的設(shè)計(jì)，并作為原單位承擔(dān)。總泵和分泵的地區(qū)之間的比例確定在輪缸活塞的力量倍增。分割系統(tǒng)的原因是，如果一個(gè)液壓回路泄漏的發(fā)展，將停止車輛。從一個(gè)液壓回路中流體的壓力提供壓力差開關(guān)的一端，并從其他電路的壓力提供給另一端。一個(gè)閥門，使真空作用于剎車踏板的行程中的比例隔膜。在其他系統(tǒng)中，從船上壓縮機(jī)的空氣壓力產(chǎn)生液壓系統(tǒng)的壓力。也就是說，他們調(diào)整后輪制動(dòng)壓力，在車輛荷載的響應(yīng)。這可以防止鎖定在濕滑路面上的前剎車燈制動(dòng)應(yīng)用。杠桿迫使制動(dòng)蹄外，他們對(duì)鼓機(jī)械棘輪被釋放，直到舉起 。前面和后輪防抱死通常是一個(gè)選項(xiàng)， GVWR 超過 10,000 磅的車輛，這是需要引導(dǎo)和驅(qū)動(dòng)橋防抱死 關(guān)閉 。 控制箱通電一系列流血輪液壓快速脈沖的單向閥。在許多應(yīng)用中，光盤上使用前軸后方的鼓。 隨著制動(dòng)器 襯片的磨損， 必須 定期 移近鼓，以確保在制動(dòng)過程中適當(dāng)?shù)慕佑|。它必須迅速制動(dòng)過程中吸收的熱量，并保持它，直到它可以將空氣中消散。作為一項(xiàng)規(guī)則，高品質(zhì)的 襯里，將顯示低于劣質(zhì)的熱褪色。加上鼓的保水的形狀，鞋和鼓之間的潮濕條件下促進(jìn) 水面滑行 。t be just one kind of brake? It39。 ? Cleanliness — hydraulic brakes are closed systems。s normal pressure forces the piston to the inoperative side, closing the contacts and illuminating a dashboard warning light. POWER ASSIST Power assist units, or boosters, reduce operator effort at the brake pedal. Vacuum boosters, popular on lightduty vehicles, make use of an engine vacuum on one side of a diaphragm, and atmospheric pressure on the other side. A valve allows the vacuum to act on the diaphragm in proportion to brake pedal travel. This assists the pedal effort, and allows increased pressure on the brake fluid, without an undue increase in pedal effort. Other types of boosters use hydraulic pressure — either from the vehicle39。 Metering valves. These hold off pressure to front disc brakes to allow rear drum brake shoes to overe returnspring pressure and make contact with the rear drums. This prevents locking the front brakes on slippery surfaces under light braking applications. These valves do not e into play during hard braking. PARKING The parking function varies greatly among hydraulic brake systems. Many lightduty vehicles with rear drum brakes use a passengercar type leverandcable setup. A ratcheted lever or foot pedal pulls a cable, which, in turn, pulls a lever assembly at each rear wheel end. The lever forces the