TH18753B - Spiral compressor - Google Patents

Abstract

DC60 (02/02/44) The stationary volute(2) and the movable volute(4) form the compression chamber(16). A first back pressure(14) is made on the back pressure surface of the movable volute(4) chamber. The first back pressure receives the discharge pressure fluid. A compressor depressor(11) is provided for the transfer of refrigerant gas from the compression chamber(16a) in the compression process to the suction port(13). A control unit(31) is provided for controlling the compressor depressor(11). When the separation force is greater than the compression force, the control unit detects and activates the compressor depressor for the transfer of fluid from the compression chamber to the suction port. Thus, a successful volute compressor is achieved by reducing the separation force when the compression force is reduced and inhibiting internal leakage. The stationary volute (2) and the movable volute (4) form the compression chamber (16). A first back pressure (14) is made on the back pressure surface of the movable volute (4) chamber. This first back pressure receives the discharge pressure fluid. A compressor depressor (11) is provided for the transfer of refrigerant gas from the compression chamber (16a) in the compression process to the suction port (13). A control unit (31) is provided for controlling the compressor depressor (11). When the separation force is greater than the compression force, the control unit detects and activates the compressor depressor for the transfer of fluid from the compression chamber to the suction port. Thus, a successful volute compressor is achieved by reducing the separation force further when the compression force is reduced and by inhibiting internal leakage.

Claims (10)

1. A helical compressor is constructed with a stationary volute (2) and a movable volute (4) for forming the compression chamber (16, 16a), an inlet (13) for drawing fluid into the said compression chamber (16, 16a), an outlet (9) for discharge of the said fluid compressed in the said compression chamber (16, 16a), a compressor depressurizing device (11) for taking the said fluid from the said compression chamber (16a) to the inlet (13), a control pathway (31) capable of operating the said compressor depressurizing device (11), and a first back pressure chamber (14) provided on the back pressure surface of either the stationary volute (2) or the movable volute (4) for receiving the said fluid with a discharge pressure. It is supplied from the outlet (9) where the control pathway (31) measures, calculates, or predicts the suction or discharge pressure, compares the separation force for separating the stationary volute (2) and the movable volute (4) from each other with the compression force for compressing one of the volutes against the other, based on the measured, calculated, or predicted suction and discharge pressures and acts on the compressor depressurization device (11) when such compression force is insufficient or will not be sufficient compared with such separation force for releasing the fluid from the compression chamber (16a) in the process of compression to the suction port (13). 2. A volute compressor complies with claim 1 in which such control pathway (31) calculates or predicts such discharge pressure and such suction pressure from the temperature of such fluid flowing through the evaporator (33) and condenser (35) connected between the outlet pipe (21) delivering such fluid and the suction pipe (20) receiving such fluid, respectively, on the outside of the housing (22). 3. A helical compressor complies with claim 1 in which such compressor depressurization device (11) has a first switch section provided on the intermediate channel of the first passage (12a, 12b) connected to the compression chamber (16a) in the process of compression at the location on the side of the suction port (13) for opening/closing the first passage (12a) with such fluid of the discharge pressure or such fluid of the suction pressure for opening the first switch section (11) by bringing such fluid of the suction pressure to the first switch section (11) and closing the first switch section (11) by bringing such fluid of the discharge pressure to the first switch section (11). 4. A volute compressor compliant with claim 1 in which it contains a second (15) back pressure chamber receiving such fluid of such discharge pressure in a condition where the compression is reduced on the back pressure surface of one of the volutes. 5. A volute compressor complies with claim 4 in which it consists of further sealing section (8) sealing the first (14) back pressure chamber and the second (15) back pressure chamber in which the fluid of the discharge pressure is reduced by flow from the first (14) back pressure chamber into the second (15) back pressure chamber through the gap in the vicinity of the sealing section (8). 6. The volute compressor complies with claim 1 in which the electric motor (24) for driving the movable volute (4) is a variable speed electric motor (24). 7. A volute compressor complies with claim 1 in which it contains the following: a vent port for directing such fluid into such compression chamber in the compression process to an area located on the side of such outlet (9), and a vent valve is provided on the intermediate or outlet section of such vent port for opening such vent port when the pressure in such compression chamber in the compression process is greater than the pressure on the side of such outlet. 8. A volute compressor is composed of a stationary volute (2) and a movable volute (4) for forming the compression chamber (16, 16a), an inlet (13) for drawing fluid into the said compression chamber (16,16a), an outlet (9) for discharge of the said fluid compressed in the said compression chamber (16,16a), a compressor depressurizing device (11) for taking the said fluid from the said compression chamber (16a) in the compression process back to the inlet (13), and a first back pressure chamber (14) is provided on the back pressure surface of either the stationary volute (2) or the movable volute (4). For receiving the said fluid, a discharge pressure is supplied from the said outlet (9), where the compressor depressurizing device (11), including the switch (11), opens/closes by operating the said discharge pressure on one side of the piston (11b), while operating the back pressure on the other side. Suction and elastic force on the other side and the said switch (11) is opened for the release of the said fluid from the said compression chamber (16a) to the said suction port (13) when the said outlet pressure is less than the said suction pressure and the said elastic force 9. A volute compressor conforming to claim 8 shall consist of a second back pressure chamber provided on the back pressure surface of one of the aforementioned volutes for the reception of such fluid at such discharge pressure in the compressible condition. 10. The volute compressor compliant with claim 9 consists of further sealing section (8) sealing the first back pressure chamber (14) and the second back pressure chamber (15) where such fluid of such discharge pressure is reduced by flow from the first back pressure chamber (14) into the second back pressure chamber (15) through an adjacent gap in the sealing section (8).