COMPRESSING CAPACITY VARYING MECHANISM IN SLIDE VANE TYPE COMPRESSOR

PURPOSE:To permit to reduce the capacity of the compressor sufficiently with a simple structure and improve the function of varying the capacity of the compressor by a method wherein an opening and closing valve, having a width narrower than a sub-suction port, is provided in the sub-suction port provided at the downstream of a main suction port so as to be capable of advancing and retreating freely into the width direction thereof and this valve is operated by a pressure difference between high and low pressure chambers. CONSTITUTION:When a room cooling load in a cabin is decreased and the pressure difference, generated between the high pressure chamber 20 and the low pressure chamber 19 in accordance with the reduction of a suction pressure, becomes lower than the set pressure of a spring 22 in the low pressure chamber 19, upon the 100% operation of the compressor, the opening and closing valve 18, provided in the sub suction port 10B provided at the downstream side of the main suction port 10A so as to be capable of advancing and retreating freely into the width direction thereof, is energized toward the high pressure chamber 20. Thus, an effect to open the sub suction port 10B may be obtained. In this case, a small capacity compression effect may be obtained but the sub suction port 10B is formed into the shape of a long hole along the compressing direction of the compressing chamber 6 and is opened and closed by advancing and retreating a valve main body 18A into the width direction thereof, therefore, a re markable capacity down effect may be obtained by the small stroke of the opening and closing valve 18.