배부식 동력분무기용 소형원심펌프 개선 = Improvement of small centrifugal pump for shoulder type power sprayer

다국어 초록 (Multilingual Abstract)

The purpose of this study was to improve the water leakage and power efficiency of the pump. The results obtained from this study which was conducted to develop a small pump through theoretical analysis, making a prototype pump and performance tests were as follows.
1. In the pump efficiency of the small pump according to the types of vortex chamber, volute type was higher than cylindrical type.
2. Inner and outer angle of impeller vane being suitable for small pump with high speed DC motor were 20 and 24 degree respectively.
3. Contents of improving the pump were to manufacture the impeller vane preciously, to make a streamline shape of impeller and reduction of the gap between pump case and impeller to reduce the friction from water flow and to prevent water leakage by means of changing the inserting method of O-ring, fitting the copper bush and filling grease into the gap of case, to change a jaw clutch instead of direct shaft connection of impeller and DC motor and to design and make the electric control circuit.
4. Under the condition of domestic test regulations which pumping pressure is 1.2㎏/㎠ and flow rate is 1200㎤/min, the continuous spraying time of newly designed prototype pump was 200 minutes which was delayed the time for 60 minutes comparing with conventional pump. And the pump efficiency of prototype was 34% which was 23% higher than that of conventional pump.