汽车系统构造(英文版)-Lesson-13-Braking-System汇总ppt课件

单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,*,单击此处编辑母版文本样式,第二级,第三级,第四级,第五级,*,*,*,Lesson 13 Braking System,Lesson 13 Braking System,1,The typical brake system consists of,disk brakes,in front and either disk or,drum brakes,in the rear connected by a system of,tubes and hoses,that link the brake at each wheel to the,master cylinder.,Other systems that are connected with the brake system include the,parking brakes,power brake booster,and the,anti-lock,system.,The typical brake system consi,2,汽车系统构造(英文版)-Lesson-13-Braking-System汇总ppt课件,3,Sketch map of the braking system,Sketch map of the braking syst,4,When you step on the brake pedal,you are actually pushing against a plunger in the master cylinder,which forces hydraulic oil(,brake fluid,)through a series of tubes and hoses to the braking unit at each wheel.Since hydraulic fluid(or any fluid for that matter)cannot be compressed,pushing fluid through a pipe is just like pushing a steel bar through a pipe.,When you step on the brake ped,5,1 Disk Brakes,The disk brake is the best brake we have found so far.Disk brakes are used to stop everything from cars to locomotives and jumbo jets.Disk brakes wear longer,are less affected by water,are self adjusting,self cleaning,less prone to grabbing or pulling and stop better than any other system around.The main components of a disk brake are the Brake Pads,Rotor,Caliper and Caliper Support.,1 Disk Brakes,6,1.1 Brake Pads,There are two brake pads on each caliper.The pads are mounted in the caliper,one on each side of the rotor.Brake linings used to be made primarily of asbestos because of its heat absorbing properties and quiet operation.Brake pads wear out with use and must be replaced periodically.,1.1 Brake Pads,7,1.2 Rotor,The disk rotor is made of iron with highly machined surfaces where the brake pads contact it.Just as the brake pads wear out over time,the rotor also undergoes some wear,usually in the form of ridges and groves where the brake pad rubs against it.,1.2 Rotor,8,Disc brake,Disc brake,9,1.3 Caliper&Support The main type of calipers is floating calipers.Calipers must be rebuilt or replaced if they show signs of leaking brake fluid.Single Piston Floating Calipers are the most popular and also least costly to manufacture and service.,1.3 Caliper&Support The ma,10,A floating caliper floats or moves in a track in its support so that it can center itself over the rotor.As you apply brake pressure,the hydraulic fluid pushes in two directions.It forces the piston against the inner pad,which in turn pushes against the rotor.It also pushes the caliper in the opposite direction against the outer pad,pressing it against the other side of the rotor.,A floating caliper floats or,11,Caliper,Caliper,12,On a,disk brake,the fluid from the master cylinder is forced into a caliper where it presses against a piston.The piston,in-turn,squeezes two brake pads against the disk(,rotor,),which is attached to the wheel,forcing it to slow down or stop.,On a disk brake,the fluid fro,13,2 Drum Brakes,Drum brakes consist of a backing plate,brake shoes,brake drum,wheel cylinder,return springs and an automatic or self-adjusting system.When you apply the brakes,brake fluid is forced under pressure into the wheel cylinder,which in turn pushes the brake shoes into contact with the machined surface on the inside of the drum.When the pressure is released,return springs pull the shoes back to their rest position.,2 Drum Brakes,14,Drum brake,Drum brake,15,Typical drum brake parts,Typical drum brake parts,16,2.1 Brake Shoes,Like the disk pads,brake shoes consist of a steel shoe with the friction material or lining riveted or bonded to it.,2.2 Backing Plate,The backing plate is what holds everything together.It attaches to the,axle,and forms a solid surface for the wheel cylinder,brake shoes and assorted hardware.,2.1 Brake Shoes,17,2.3 Brake Drum,Brake drums are made of iron and have a machined surface on the inside where the shoes make contact.,2.4 Wheel Cylinder,The wheel cylinder consists of a cylinder that has two pistons,one on each side.Each piston has a rubber seal and a shaft that connects the piston with a brake shoe.When brake pressure is applied,the pistons are forced out pushing the shoes into contact with the drum.,2.3 Brake Drum,18,2.5 Return Springs,Return springs pull the brake shoes back to their rest position after the pressure is released from the wheel cylinder.A good technician will examine the springs during a brake job and recommend their replacement if they show signs of fatigue.,2.5 Return Springs,19,2.6 Self Adjusting System,The parts of a self adjusting system should be clean and move freely to insure that the brakes maintain their adjustment over the life of the linings.,With,drum brakes,fluid is forced into the wheel cylinder,which pushes the brake shoes out so that the friction linings are pressed against the drum,which is attached to the wheel,causing the wheel to stop.,2.6 Self Adjusting System,20,3 Parking Brakes,The park