Investigation of A New Wedge Disc Brake Mechanism

Most cars' front brakes are of the disc type, but the rear brakes are of the drum type. Older cars often had drum brakes on all four wheels, and many new cars now have four-wheel disc brakes. The aim of this research is to investigate the ability of manufacturing and testing a new mechanism for wedge disc brake. The new mechanism consists mainly of the wedge itself, which is controlled by a gear set to change its inclination angle. The wedge is sliding on a surface controlling its inclination angle. The control of the inclination angle can change the factor between the applied force from the brake pressure source and the normal force to the brake pads. Changing the normal force to the brake pads can change the brake force on the rotor disc. The brake force from the pads on the rotor disc is the main goal in this research. The goal is to increase this force by increasing the normal force on the brake pads. The new mechanism was manufactured and tested experimentally in the laboratory by the use of a lathe machine carrying the mechanism for investigation. The results showed the ability of the new mechanism to increase the brake force by about seven times than conventional disc brake. The tested inclination angles were 45o , 35o , 25o , 15o , 12o and 10o with different rotational speeds of 76, 150, 230 and 305 rpm at different applied hydraulic pressures of 5, 7.5, 10 and 12.5 bar. In all the above-mentioned cases, the inclination angle of 12o was found to be the best angle in increasing the brake force.