|Published (Last):||23 August 2014|
|PDF File Size:||13.80 Mb|
|ePub File Size:||13.45 Mb|
|Price:||Free* [*Free Regsitration Required]|
When an hydraulic brake is applied fluid is required to move through the pipes. The changes in axle loads during braking bears no relationship to which axles are braked. For dry discs it is assumed to be:.
Brake Design and Calculation
Pxf is not the driver reaction time but the system reaction time. Ignoring the inertia of the wheels the required dynamometer inertia is given by.
If the braked wheel is very light on an incline then it is possible the tyre will slip before the brake. Odwnload is the average power, the peak power at the onset of braking is double disc brake design calculations pdf download. Some of the stop energy is dissipated in the tyre as wheel slip. Assuming the stop is from the test speed down to zero then the kinetic energy is given by: The front axle load cannot be greater than the total vehicle mass. Pipe expansion is very small and unlikely to be of interest however it should be noted that it is proportional to the cube of the diameter, so using bigger pipe than necessary on a system with a fixed fluid volume will cause longer travel for two reasons, the stiffness of the pipe and more importantly the additional fluid compression losses.
The following components need fluid: Fluid losses in master disc brake design calculations pdf download increase with bore size and pressure.
Ball ramp brakes have a self servoing effect rather like a drum brake. Only disc brake design calculations pdf download the brake is applied but rotating is energy being dissipated in the brake system. In order to approximate the temperature rise of diwc disc an assumption as to where the energy is going has to be made. For a disc brake the following approximation can be used:. It is also needed to compensate for lack of stiffness of the brake housing.
Use them at your risk It can be calculated:. The traction force required to park the vehicle is:. Hill hold is usually required with the vehicle facing both up and down the hill. The braking force can only be generated if the wheel does not lock because the friction of a sliding wheel is much lower than a rotating one.
They only depend on the static laden conditions and the deceleration. The brake factor multiplies the output torque. For some legislation the distribution between front and pfd brakes is laid down. The energy to each brake depend on the number of brakes and the proportion of braking on each axle. It assumes the vehicle is either braking or not.
This air is squashed totally flat during braking. Pad compressibility varies between hot and cold conditions. Brame losses are disc brake design calculations pdf download inconsiderable and vary depending on the number and angle of bends.
Pressure is disc brake design calculations pdf download function of the required clamp load and the piston area. The rear axle load is the difference between the vehicle mass and the front pdt load. This may be achieved by varying the brake size or more likely using a valve to reduce the actuation pressure.
Many brakes do not run at the same speed as the wheels so it is important brkae understand how the brake will be mounted on the rig.
A reasonable assumption can be found by using the following: A measure of sensitivity is the amount the brake factor varies for a change in lining friction. Especially at full travel. In practice it takes a time for the system pressure to rise and the friction to build up. When testing Brakes on a dynamometer it is disc brake design calculations pdf download to calculate the inertia requirements.
This page pulls them together with just a little explanation. The deceleration used in calculations is a steady state one called MFDD mean fully developed deceleration.
DESIGN AND ANALYSIS OF BRAKE ROTOR WITH PARAMETER OPTIMIZATION | TJPRC Publication – 01
When parking on an incline the disc brake design calculations pdf download axle has a higher load than it does on the level. For calculations a linear build up over 0. Fluid compression varies with temperature and the type of fluid used.
The pedal return springs may make a significant contribution to the overall pedal force. It can lift off the ground though.
Having decided which wheels will need braking to generate sufficient braking force the torque requirements of each wheel need to be determined.
Brake Design and Calculation
Where a calculation requires a stopping distance or an average stop deceleration then this delay must be taken into account. The rotational energy is the energy needed to slow rotating parts.
The maximum braking force possible on any particular axle before wheel lock is given by:. The output will have at least two slopes but will also have a dead band at the bottom. High factor brakes become very disc brake design calculations pdf download to manufacturing tolerances and lining friction variations.