| 摘要 |
<p>PURPOSE:To prevent an excessive increase of calorific power of an engine in its high speed operational range, by open-close controlling a bypass passage of the supercharge engine through a pressure actuated member, increasing pressure of a pressure source in accordance with an increase of speed of the engine and applying pressure of the pressure source to said pressure actuating member. CONSTITUTION:A supercharger 12 comprises a turbine 10, arranged in an exhaust passage 22, and a blower 8, arranged in an intake passage 18. A secondary throuttle valve 30, controlled by the first diaphragm device 28, is set in the in the intake passage 18. A bypass control valve 34, controlled by the second diaphragm device 32, is arranged in a bypass passage 24 of the turbine 10. When an engine increases its speed to exceed a prescribed level, resultant pressure of supercharge pressure and output pressure of an air pump 54, increasing pressure inaccordance with the speed of the engine, is applied to the second diaphragm device 32, and the bypass control valve 34 is further opened. In this way, supercharge pressure is decreased, and calorific power and exhaust temperature of the engine can be prevented from excessively increasing to improve durability.</p> |
