Hydraulic braking systems

Hydraulic braking systems

• 2.
   The technologyof controlling pressurized fluids to create  force and motion is known as Hydraulics . HYDRAULIC PRINCIPLES:  Fluids cannot be compressed  Fluids can transmit Movement • Acts “Like a steel rod” in a closed container • Master cylinder transmits fluid to wheel cylinder or • caliper piston bore.  Fluids can transmit and increase force PRESSURE =FORCE / AREA
• 4.
  Of course ,thefinal contact between vehicle and road made through tyres -hence it is of great importance in braking system. Bald or defective tyres will even make the best brakes ineffective. The braking systems which works with the help of hydraulic principles is known as hydraulic braking systems.
• 5.
  HYRAULIC BRAKING SYSTEMCAN BE OPERATED BY Vacuum, Hydro or Motor assisted Disc System Drum System Dual System
• 6.
  DRUM BRAKE MASTER CYLINDER DISK BRAKE BRAKEPEDAL
• 7.
  HYDRAULIC PRESSURE ISDISTRIBUTED EQUALLY IN ALL DIRECTIONS BY THE SAME PRINCIPLE ……….
• 8.
  SAME LINE OFPRESSURE WILL BE EXERTED ON ALL WHEELS
• 9.
  The Hydraulic pressureis the same, but the applied force can be changed by the piston size.
• 10.
  Expanding shoes createforce on the inner surface of the drum Used on the rear of some trucks and SUV’s Self-energizing design requires less activation force Require periodic adjustment
• 12.
  DISK BRAKES WORKSWITH THE HELP OF CALIPERS
• 13.
  FIXED CALIPERS Calipers aredisc brakes that use a caliper that is FIXED in position and does not slide. -They have pistons on both sides of the disc. -There may be 2 or 4 pistons per caliper FLOATING CALIPERS -Much more common -Single Piston -Easier to work with -On “inboard” side of caliper Calipers are of two types
• 14.
  Applies two pistonsto opposite sides of rotor Caliper stays stationary Disc Brakes require higher hydraulic pressure -Motorcycles and some import trucks and cars use this type -Similar to bicycle brakes
• 15.
  .Applies pressure totwo pads on opposite sides of rotor .Caliper -Sliding -Fixed .Friction Material exposed to air
• 17.
  THIS CONDITION WILLOCCUR IF THERE IS MORE FRONT BRAKE TORQUE THAN DYNAMIC FRONT WEIGHT THIS CONDITION WILL OCCUR IF THERE IS MORE REAR TORQUE THAN DYNAMIC REAR WEIGHT
• 18.
  Optimum braking isachieved when brake torque distribution matches dynamic weight distribution TO ACHIEVE THIS CONDITION PROPORTIONATING VALVES ARE USED When a vehicle brakes , weight is transferred to the front.the nose will dip as it gets heavier and rear will rise as it gets lighter.The rear needs less hydraulic pressure. Proportionating valves are used to provide balanced braking by reducing hydraulic pressure to rear wheel
• 19.
  When a largevariation at axle loading takes place, such as railway wagons , trucks ,load or height sensitive proportionating valves regulate more hydraulic pressure to the rear axle in the amount needed. Some vehicles with front/ rear split braking systems have a proportionating valve by-pass which allows full pressure to rear axle if front brakes fails.
• 20.
  Properties of BrakeFluid Does not thicken or then with changing heat Must not boil Must be compatible with brake parts material Must lubricate internal parts Must not evaporate easily The fluid through which the energy is passed in hydraulic braking systems is known as BRAKE FLUID