الفهرس 
chapter One: IntroductionOnly 14 pages are availabe for public view
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Abstract
The aim of this study is to investigate the ability of manufacturing and testing a new mechanism for wedge disc brake. This mechanism is designed and constructed in Mechanical Workshop, Faculty of Industrial Education, Beni-Suef University, in order to increase the brake force. 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 workshop 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 fourteen times compared to 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 mentioned cases the inclination angle of 12o, applied pressure of 12.5 bar and rotational speed of 76 rpm were found to be the best condition in increasing the brake force.
The results indicated that, the applied force and wedge inclination angle have the effect on increasing the brake force but the rotational speed has the effect on decreasing the brake force. The brake force generally fluctuates as function of braking time and decreases at high braking conditions.
Based on design of experiments (DOE) using Taguchi method of optimization by Minitab 16 software, to identify the contributions of different operation parameters and their interaction on the brake force. They are: inclination angle contributes by 45.84 % of the system performance and it is followed by applied pressure of 29 % and rotational speed by 20.76 % but sand and oil contributes 2.23 and 2.15 % respectively.