Brake Apply System [service Brake & Parking Brake]

Summary

The video provides an in-depth overview of vehicle braking systems, focusing on the essential components of service and parking brakes. It explains the structure and function of brake pedals, hydraulic systems, and various types of brake switches. The importance of proper brake pedal height and free play for safety is emphasized, alongside the mechanics of parking brakes, including different lever types and cable systems. The content covers both traditional and modern braking technologies, ensuring a comprehensive understanding of how these critical systems operate in vehicles.

Takeaways

• 🚗 Vehicles must have two independent braking systems: service and parking brakes.
• 🔧 The brake pedal consists of multiple components, including the pedal lever and brake light switch.
• ⚙️ Brake light switches can be mechanically or hydraulically operated and are essential for many vehicle systems.
• 📏 Proper brake pedal height and free play are crucial for effective brake function and safety.
• 🅿️ The parking brake is an independent system that operates only on the rear wheels, used to hold a parked car in position.
• 🔗 Various types of parking brake levers exist, including stick, pedal, and center lever designs.
• 🛠️ The parking brake system includes linkages and cables that transmit force to the brake assemblies.
• 🔄 There are different styles of rear parking brake systems, including service-type and exclusive parking brake designs.
• ⚙️ Drum-in-hat systems provide a high-performance parking brake using a dedicated set of brake shoes.
• 🚧 Transmission brakes are primarily used in trucks and buses, providing effective parking brake functionality.

Q & A

What are the two main independent brake systems required in vehicles?

Vehicles must be fitted with at least two independent systems: the service brake and the parking brake.

How does the hydraulic brake system function in light vehicles?

The hydraulic brake system operates through a foot brake that affects all wheels, utilizing a brake pedal connected to various components including a pedal lever and a brake lamp switch.

What is the purpose of the brake light switch?

The brake light switch turns on the brake lights when the pedal is pressed and sends a signal to the vehicle's computer indicating that the brakes are applied.

How is brake pedal height adjusted?

Brake pedal height is adjusted using the push rod and clevis to ensure proper pedal position for optimal brake function.

What is brake pedal free play and why is it important?

Brake pedal free play is the distance the pedal travels before resistance is felt. Proper free play prevents the brakes from being lightly applied at all times, which can cause overheating and premature wear.

What is the primary function of the parking brake system?

The parking brake system is a secondary braking system used to hold a parked vehicle in position, operating independently of the hydraulic brake system.

What are the different types of parking brake levers mentioned?

Different types of parking brake levers include stick levers, pedal parking brakes, and center lever systems, each varying in design and operation.

What is an integral drum parking brake, and how does it operate?

An integral drum parking brake mechanically applies rear drum service brakes when the parking brake is engaged, using components like actuator levers and struts.

What is the difference between service type and exclusive parking brake systems?

Service type parking brakes use parts of the ordinary service brake mechanism, while exclusive parking brake systems operate independently of the service brake.

How does a drum in hat parking brake system function?

The drum in hat system consists of a simple drum brake shoe assembly that applies against a drum inside the rotor hat section, providing high performance for parking brake functionality.