【正文】
= 0? ,則稱 0? 為 同步附著系數(shù) 。由式 ()、式 ()得在任何附著系數(shù) ? 的路面上,前、后車輪同時抱死即前、后軸車輪附著力同時被充分利用的條件是: GFFFF BBff ????? 2121 )/()(// 122121 ggBBff hLhLFFFF ?? ???? () 沈陽理工大學(xué)學(xué)士學(xué)位論文 14 式中:1fF—— 前軸車輪的制動器制動力, 111 ZFF Bf ???; 2fF—— 后軸車輪的制動器制動力, 222 ZFF Bf ???; 1BF—— 前軸車輪的地面制動力; 2BF—— 后軸車輪的地面制動力; 1Z , 2Z —— 地面對前、后軸車輪的法向反力; G—— 汽車重力; 1L , 2L —— 汽車質(zhì)心離前、后軸距離; gh —— 汽車質(zhì)心高度。此后制動力矩 fT 即表現(xiàn)為靜摩擦力矩,而 eff rTF /? 即成為與 BF 相平衡以 圖 制動力與踏板力 PF 的關(guān)系 圖 制動時的汽車受力圖 阻止車輪再旋轉(zhuǎn)的周緣 力的極限值。 假設(shè) 當(dāng)時速 0 8 0 / 2 2 .2 /v Km h m s??,至汽車停止時速度 0tv? 。 綜上所述,本次商務(wù)車設(shè)計,前后輪均 采用浮動鉗盤式制動器。根據(jù)制動盤的不同,盤式制動器還可分為普通盤式和通風(fēng)盤式。所以,現(xiàn)代轎車的車輪除了使用鋁 合金車圈來降低運行溫度外,還傾向于采用散熱性能較好的盤式制動器 。 ( 2) 兼作駐車制動器時,所需附加的手驅(qū)動機構(gòu)比較復(fù)雜。 ( 4) 易于構(gòu)成雙回路制動系,使系統(tǒng)有較高的可靠性和安全性。 這種制動器具有以下優(yōu)點:僅在盤的內(nèi)側(cè)有液壓缸,故軸向尺寸小,制動器能進(jìn)一步靠近輪轂;沒有跨越 制動盤的油道或油管加之液沈陽理工大學(xué)學(xué)士學(xué)位論文 8 壓缸冷卻條件好,所以制動液汽化的可能性小 。其浮動方式有兩種,一種是制動鉗體可作平行滑動;另一種是制動鉗體可繞一支承銷擺動。對雙向增力式制動器來說,不論汽車前進(jìn)制動或倒退制動,該制動器均為增力式制動器。 ( 3) 雙向雙領(lǐng)蹄式制動器 如圖 ( d) 當(dāng)制動鼓正向和反向旋轉(zhuǎn)時,兩制動助均為領(lǐng)蹄的制動器則稱為雙向雙領(lǐng)蹄式制動器。領(lǐng)蹄所受的摩擦力使蹄壓得更緊,即摩擦力矩具有 “ 增勢 ” 作用,故又稱為增勢蹄;而從蹄所受的摩擦力使蹄有離開制動鼓的趨勢,即摩擦力矩具有 “ 減勢 ” 作用,故又稱為減勢蹄。車輪制動器的制動鼓均 固定在輪鼓上。 課題研究方案: 1)制動器的結(jié)構(gòu)方案分析及選擇。 5)制動能力的熱穩(wěn)定性良好。有一個 巨大的汽車現(xiàn)有及潛在的市場的吸引,各種先進(jìn)的電子技術(shù)、生物技術(shù)、信息技術(shù)以及各種智能技術(shù)才不斷應(yīng)用到汽車制動控制系統(tǒng)中來。另外,國內(nèi) 還 有人研究采用水鎂石做摩擦材料。隨著 BBW 技術(shù)的發(fā)展,盤式電動制動器是未來發(fā)展的重點方向。雖然盤式制動器的使用經(jīng)濟 性現(xiàn)在有所提高,但是與鼓式制動器比起來還是貴得多。 專門用于掛車的還有慣性制動系和重力制動系。 關(guān)鍵詞 : 盤式 制動器 CAD MATLAB 設(shè)計 建模 沈陽理工大學(xué)學(xué)士學(xué)位論文 VI Abstract Brake is an important part of brake system, this paper mainly introduces the design of mercial vehicle brake. From the parison of drum brake and disc brake about the structure and performance, because the discbrake braking performance is better, and size and quality are relatively small, thermal performance is good, and the mercial vehicle designed torque and power is larger, high speed, good performance, belongs to highgrade car, so this design sense are chosen floating disc brakes. This paper start the following steps after selecting the basic structure. First, the parameters of braking power distribution coefficient include: adhesion coefficient, synchronous adhesion coefficient, strength, and brake, and maximum braking torque parameters calculation, etc. The second brake and its ponents: the brake disc and calliper, friction lining block size of ponents etc brake calculation and material selection, The third in the design in the rear brake selection in the rear brake disc, install the parking brake on the mechanical structure, Fourth: brake wheel drive mechanism brake cylinder, the brake pedal stroke the cylinder, and the design calculation. After the design of brake ,this paper start the checking of braking deceleration and braking distance, analyzed the stability of braking efficiency and braking direction, and drawn out with MATLAB braking force distribution curve, above all ply with the design requirements, and verifies the rationality of the design of the brakes. Finally, according to the design and calculation using CAD drawing brake assembly and brake caliper disc brake, piston, liner, friction parts ,at the same time ,the paper also carried a threedimensional modeling. In addition, this paper briefly introduces the drive mechanism brake type selection, brake main cylinder pipe, braking system, the selection of multiloop research status of brake and development prospects. Key words: brake disc CAD MATLAB design modeling 沈陽理工大學(xué)學(xué)士學(xué)位論文 VII 目 錄 摘要 ................................................................... I 1 緒論 ................................................................. 1 制動系統(tǒng)的基本概念 ............................................................................................. 1 制動系統(tǒng)研究現(xiàn)狀 ................................................................................................. 2 ......................................................................................................... 3 ......................................................................................................... 4 2 制動 器 的結(jié)構(gòu)形式選擇 ................................................. 5 式制動器結(jié)構(gòu)形式簡介 ..................................................................................... 5 式制動器 結(jié)構(gòu)形式簡介 ..................................................................................... 7 制動器的 優(yōu)缺點 ............................................................................................. 8 的最終 選擇 ......................................................................... 8 3 制動系的主要參數(shù)及選擇 .............................................. 10 ................................................................................... 11 ....................................................................................................... 15 附著系數(shù)利用率 ............................................................................... 17 ........................................................................................... 18 制動器因數(shù) .......................................................................................................... 19 盤式制動器主要參數(shù)的確定 ............................................................................... 20 4 制動器的設(shè)計計算 .................................................... 21 算 ................................................................................... 21 比能量耗散率 ............................................................................................ 21 比滑磨功 .................................................................................................... 22 器熱容量和溫升核算 ................................................................................... 23 計算 ............................................................................... 24 計算 ....................................................................................................... 25 5 制動器主要零部件的結(jié)構(gòu)設(shè)計與計算 ..............................