Design and construction of a pedal powered dough mixer.

Abstract

An efficient dough mixing helps to; increase bread quality, production performance of bread minimizes time wastage, prevent labor drudgery. The objectives of this research were to design and assemble different components, test the performance and to carry out cost benefit analysis of the. prototype. The dough mixed was ready enough for use and the prototype is designed ready for production- with the provision for repair and maintenance by the small and medium scale producers of bread. In this -research, a motorized dough mixer was designed and fabricated. The machine essentially consists of a single phase electric motor with a design capacity of 70kg/hr for 6kg per batch 70kg/hr. The machine works on the principle that the gearbox reduces the motor speed to suit relatively high torque required during agitation. The dough is then manually removed from the mixing bowl. A pedal powered. dough mixer prototype operated manually by peddling using human tabor. The prototype had an efficiency and design capacity of 75% 40kg/hr respectively. During testing I discovered that the porotype works best for 3kg per batch. There was no any loss obtained during the mixing operation. 1he principle of operation of the prototype is based on the energy transmission from the pinion of the convectional bicycle unit to processing unit through the rotary shafts. From the economic evaluation using the net present value method with a huddle rate of with the Net Present Value of 31,890,517 Uganda shillings. The machine efficiency was influenced by the feed quantity of wheat flour mixing proportions. The operation requires technical skills for its smooth operation especially in aligning the mixing bowl base. from the bottom level of the agitator. Key words: wheat flour, mixing bowl, dough mixer and dough.