Transfer of power to the brake.
In a brake power must be transferred as efficiently as possible by hand or foot into the brake.
For the transfer of the force of the hand or foot to the brake to the wheel, the following four different operating systems are used:
- Tie rods
- The chain
The cable connection is most commonly used to transfer the force of the hand brake. The cable consists of an inner cable that slides into an outer casing.
The inner cable is attached to the handle and lever in the brake.
The outer casing bears against the fixed part of the brake lever and against a cam of the brake (side-pull-up brakes and V-brakes) or on the frame (with drum brakes, and pull-up mid-braking).
By losses in the cable is the force that pulls the lever to the cable.
The losses are caused by friction between the inner and outer casing.
This increases as the coefficient of friction is larger, there is more dirt in the cable, the number of bends in the cable is larger and the force in the cable increases.
Losses in the cable may be significant, and are more than 50% at a cable used.
Another disadvantage of the cable control is the low stiffness.
Due to elongation in the inner and outer casing, the displacement of the brake are smaller than the displacement at the brake lever.
In case of hydraulic brakes, the cylinders are connected by pipes.
Herein almost no losses occur. The friction in the pipe is virtually zero. Also elaborate curves do not lead to additional losses.
The stiffness of the hydraulic pipes is also larger. Brakes operated by hydraulic lines then also serves a higher return than brake cable.
Another important advantage of hydraulic actuated brakes is that they are better to be metered.
Ordinary cables suffer from the so-called slick slip phenomenon.
Because the coefficient of friction between the inner and outer casing is greater if they stand in relation to each other that if they move, the brake reacts a little bit slow and jerky on the force applied by the friction suddenly be somewhat lower if the cable starts to move.
Braking operates with hydraulic brake lines responds instantly to the force applied.
Drum brakes are sometimes operated by means of a rod mechanism.
Losses occur in the hinge points. The friction of the pivot points is less than the friction between the outer and inner cable.