Development of a three-dimensional scroll compressor

Scroll compressor has been employed in various appliances due to its advantages such as high efficiency and low vibration. For the purpose of further performance improvement in scroll compressor, the authors have developed a new conceptual three-dimensional compression mechanism (three-dimensional scroll) by adding an axial compression to the conventional radial compression. By realizing three-dimensional compression, which has been impossible for the conventional scroll, higher efficiency, higher reliability, and smaller size are achieved. Since the three-dimensional scroll has steps in scroll tip and end plate, the key point of efficiency improvement in the three-dimensional scroll is to minimize the gas leakage in the steps. Through cylinder pressure measurements and visualization tests, characteristics of the leakage in the steps are obtained and the optimum clearance ranges are determined. Based on this, the authors have developed high efficiency, small size, and lightweight three-dimensional scroll compressor for commercial air-conditioner. The developed three-dimensional scroll compressor archived 35 per cent smaller size, 26 per cent lighter weight, and 5.5 per cent improvement of efficiency compared with the conventional one.