Rotary compressor and heat pump system

Abstract

A problem to be solved by the present invention is that the temperature of a refrigerant discharged from a compression section can be detected more exactly without being influenced by variable factors existing around the compression section. In a rotary compressor 1 having a motor 6 and a compression section 3 provided in a closed container 2 , and also having a discharge pipe 26 provided in an upper part of the closed container 2 to discharge a refrigerant compressed by the compression section 3 to the outside of the closed container 2 , a refrigerant discharge part 462 for discharging the refrigerant compressed by the compression section 3 toward the inner peripheral surface of the closed container 2 is provided, and a discharge temperature sensor 20 for detecting the discharge temperature of compressed refrigerant is arranged in a portion opposed to the refrigerant discharge part 462 on the outer peripheral surface side of the closed container 2.

1 . A rotary compressor comprising:
 a cylindrical closed container arranged vertically;   a motor provided in an upper part of the closed container; and   a compression section which is provided in a lower part of the closed container and is driven by a shaft fixed to a rotor of the motor,   the compression section having:   a cylinder provided with a compression chamber therein;   an upper bearing and a lower bearing each of which is fixed to the cylinder and has an end plate part for closing the end surface of the compression chamber and a bearing part for rotatably supporting the shaft;   a compression section discharge hole which is provided in the end plate part of the upper bearing and is open to the compression chamber;   an upper muffler cover which is fixed on the upper side of the end plate part of the upper bearing and forms an upper muffler chamber by covering the compression section discharge hole;   an upper muffler discharge hole which is provided in the upper muffler cover and is open to the closed container; and   a discharge pipe which is provided in an upper end part of the closed container to discharge a refrigerant in the closed container to the outside of the closed container, wherein   a discharge temperature sensor for detecting the temperature of compressed refrigerant is provided on the outer peripheral surface of the closed container approximately at the height at which the upper muffler discharge hole is positioned.   
   
   
       2 . The rotary compressor according to  claim 1 , wherein
 the upper muffler cover has a horizontal end plate part, a vertical side plate part, and an upper muffler discharge hole which is provided in the side plate part and is open toward the inner peripheral surface of the closed container; and   a discharge temperature sensor for detecting the temperature of compressed refrigerant is provided on the outer peripheral surface of the closed container opposed to the upper muffler discharge hole.   
   
   
       3 . The rotary compressor according to  claim 1 , wherein
 the upper muffler cover has a horizontal end plate part, a vertical side plate part, and a cut and raised part which is provided in the end plate part and is open toward the inner peripheral surface of the closed container as an upper muffler discharge hole; and   a discharge temperature sensor for detecting the temperature of compressed refrigerant is provided on the outer peripheral surface of the closed container opposed to the upper muffler discharge hole.   
   
   
       4 . The rotary compressor according to  claim 1 , wherein
 the upper muffler cover has an upper muffler pipe which is fixed to the upper muffler cover and one end of which is open to the upper muffler chamber and the other end of which is open toward the inner peripheral surface of the closed container as an upper muffler discharge hole; and   a discharge temperature sensor for detecting the temperature of compressed refrigerant is provided on the outer peripheral surface of the closed container opposed to the upper muffler discharge hole.   
   
   
       5 . The rotary compressor according to  claim 1 , wherein
 the upper muffler cover has a horizontal end plate part, a vertical side plate part, a projecting part provided in the side plate part so as to be close to the inner peripheral surface of the closed container, and an upper muffler discharge hole which is provided in the projecting part and is open toward the inner peripheral surface of the closed container; and   a discharge temperature sensor for detecting the temperature of compressed refrigerant is provided on the outer peripheral surface of the closed container opposed to the upper muffler discharge hole.   
   
   
       6 . The rotary compressor according to  claim 1 , wherein
 the end plate part of the upper bearing has a bearing end plate discharge passage one end of which is open to the upper muffler chamber and the other end of which is open toward the inner peripheral surface of the closed container as an upper muffler discharge hole; and   a discharge temperature sensor for detecting the temperature of compressed refrigerant is provided on the outer peripheral surface of the closed container opposed to the upper muffler discharge hole.   
   
   
       7 . The rotary compressor according to  claim 1 , wherein the number of revolutions of the rotary compressor is variable. 
   
   
       8 . The rotary compressor according to  claim 1 , wherein the compression section has a low stage side compression section arranged on the lower side, a high stage side compression section arranged on the upper side, an intermediate interconnection passage which connects the discharge side of the low stage side compression section to the suction side of the high stage side compression section, a low-pressure suction pipe connected to the suction side of the low stage side compression section, and an intermediate-pressure suction pipe connected to the intermediate interconnection passage. 
   
   
       9 . A heat pump system comprising a refrigeration cycle in which a compressor, a condenser, an expansion mechanism, and an evaporator are connected in succession by a line; and a control unit which detects the temperatures of a plurality of locations of the refrigeration cycle and controls the number of revolutions of the compressor and the throttle amount of the expansion mechanism, wherein
 the rotary compressor described in  claim 1  is used as the compressor; and   based on the temperature detected by a discharge temperature sensor provided on the outer peripheral surface of a closed container of the compressor, the throttle amount of the expansion mechanism and the number of revolutions of the compressor are controlled, and the degree of superheat of a refrigerant sucked into the compressor is kept proper.   
   
   
       10 . A heat pump system provided with a gas injection cycle, which comprises a basic refrigeration cycle in which a compressor, a condenser, a basic cycle expansion mechanism, and an evaporator are connected in succession by a line; a branch pipe which branches some of a high-pressure refrigerant behind the outlet of the condenser from the basic refrigeration cycle as an injection refrigerant; an injection expansion mechanism which decompresses the injection refrigerant to an intermediate pressure between the pressure of the condenser and the pressure of the evaporator; an internal heat exchanger which heat-exchanges the decompressed injection refrigerant with the branched high-pressure refrigerant of basic refrigeration cycle; an injection line which sucks the injection refrigerant, having been subjected to the heat exchange, during the compression process of the compressor; and a control unit which detects the temperatures of a plurality of locations of the refrigeration cycle and controls the number of revolutions of the compressor, the throttle amount of the basic cycle expansion mechanism, and the throttle amount of the injection expansion mechanism, wherein
 the rotary compressor described in  claim 8  is used as the compressor, the discharge pipe of the compressor is connected to the condenser, the low-pressure suction pipe of the compressor is connected to the evaporator, and the intermediate-pressure suction pipe of the compressor is connected to the injection line; and   based on the temperature detected by a discharge temperature sensor provided on the outer peripheral surface of a closed container of the compressor, the throttle amount of the injection expansion mechanism and the number of revolutions of the compressor are controlled, and the degree of superheat or the dryness of a refrigerant sucked into the intermediate-pressure suction pipe of the compressor is kept proper.   
   
   
       11 . A heat pump system provided with a gas injection cycle, which comprises a basic refrigeration cycle configured by connecting a compressor, a condenser, a first expansion mechanism, an intermediate-pressure gas-liquid separator, a second expansion mechanism, and an evaporator in succession by a line; an injection pipe which branches a gas refrigerant separated by the intermediate-pressure gas-liquid separator from the basic refrigeration cycle as an injection refrigerant and sucks the injection refrigerant during the compression process of the compressor; and a control unit which detects the temperatures of a plurality of locations of the refrigeration cycle and controls the number of revolutions of the compressor, the throttle amount of the first expansion mechanism, and the throttle amount of the second expansion mechanism, wherein
 the rotary compressor described in  claim 8  is used as the compressor, the discharge pipe of the compressor is connected to the condenser, the low-pressure suction pipe of the compressor is connected to the evaporator, and the intermediate-pressure suction pipe of the compressor is connected to the injection line; and   based on the temperature detected by a discharge temperature sensor provided on the outer peripheral surface of a closed container of the compressor, the throttle amount of the first expansion mechanism, the throttle amount of the second expansion mechanism, and the number of revolutions of the compressor are controlled, and the degree of superheat or the dryness of a refrigerant sucked into the intermediate-pressure suction pipe of the compressor is kept proper.