Compressor and refrigerating apparatus having the same

Abstract

A scroll compressor and a refrigerating apparatus having the same are provided. In the scroll compressor, an angle formed between an injection passage that guides refrigerant from a condenser back into an intermediate compression chamber and a back pressure passage that guides refrigerant from the intermediate compression chamber into a back pressure chamber may be designed so as to prevent leakage of refrigerant from the intermediate compression chamber into the back pressure chamber. This allows an appropriate pressure to be maintained the back pressure chamber, and increases an amount of refrigerant supplied into the compression chambers, thereby improving performance of the scroll compressor and a refrigerating apparatus in which such a scroll compressor is installed.

1 . A scroll compressor, comprising:
 a casing;   a fixed scroll fixed to an interior of the casing;   an orbiting scroll movably engaged with the fixed scroll so as to form compression chambers therebetween that are consecutively moved as the orbiting scroll moves relative to the fixed scroll;   a back pressure chamber formed at a bearing surface formed between the fixed and orbiting scrolls, wherein the back pressure chamber is configured to support a position of the orbiting scroll against the fixed scroll;   a first passage formed in one of the fixed scroll or the orbiting scroll and configured to guide refrigerant compressed in the compression chambers back into the back pressure chamber; and   a second passage formed at the one of the fixed scroll or the orbiting scroll and configured to guide refrigerant, which has been discharged from the compression chambers into a refrigerating cycle, back into the compression chambers from an intermediate portion of the refrigerating cycle.   
   
   
       2 . The compressor of  claim 1 , further comprising a main frame fixed to the interior of the casing so as to support the fixed scroll and the orbiting scroll. 
   
   
       3 . The compressor of  claim 2 , wherein the back pressure chamber is defined by a recess formed in an upper surface of the main frame, a lower surface of the fixed scroll, and an outer peripheral portion of the orbiting scroll. 
   
   
       4 . The compressor of  claim 3 , further comprising a groove formed in the lower surface of the fixed scroll so as to provide for communication between the first passage, which is formed in the fixed scroll, and the back pressure chamber. 
   
   
       5 . The compressor of  claim 4 , wherein the first passage comprises:
 a first bypass hole having a first end connected to the communication groove;   a second bypass hole having a first end alternately connected to the compression chambers as the orbiting scroll moves relative to the fixed scroll; and   a third bypass hole that connects second ends of the first and second bypass holes.   
   
   
       6 . The compressor of  claim 5 , further comprising a blocking member positioned in an external end of the third bypass hole so as to seal the first passage. 
   
   
       7 . The compressor of  claim 1 , wherein the second passage comprises:
 a first injection hole that extends into a plate portion of the fixed scroll; and   a second injection hole having a first end connected to the first injection hole and a second end that alternately communicates with the compression chambers.   
   
   
       8 . The compressor of  claim 7 , wherein an inlet end of the first injection hole is connected to an injection pipe that extends through an outer wall of the casing so as to receive refrigerant from an intermediate section of a refrigerating cycle and to direct the received refrigerant back into the compression chambers through the second passage. 
   
   
       9 . The compressor of  claim 1 , wherein the first passage is formed in the fixed scroll and is configured to communicate with one of the compression chambers at an intermediate pressure between a suction pressure and a discharge pressure. 
   
   
       10 . The compressor of  claim 1 , wherein the second passage is formed in the fixed scroll and is configured to with one of the compression chambers at an intermediate pressure between a suction pressure and a discharge pressure. 
   
   
       11 . The compressor of  claim 1 , wherein an angle between the first passage and the second passage is greater than approximately 30°. 
   
   
       12 . The compressor of  claim 11 , wherein an outlet of the first passage is closer to a discharge side of the compression chambers than an outlet of the second passage is. 
   
   
       13 . The compressor of  claim 1 , wherein a diameter of an outlet of the second passage is greater than or equal to a diameter of an outlet of the first passage. 
   
   
       14 . A refrigerating apparatus comprising the scroll compressor of  claim 1 . 
   
   
       15 . A scroll compressor, comprising:
 a fixed scroll having spiral fixed wraps formed thereon;   an orbiting scroll having spiral orbiting wraps formed thereon, wherein the spiral orbiting wraps are engaged with the spiral fixed wraps so as to form a pair of compression chambers that are consecutively moved as the orbiting scroll orbits relative to the fixed scroll;   a back pressure chamber formed at an outer peripheral portion of the orbiting scroll, wherein the back pressure chamber receives bypassed refrigerant from the pair of compression chambers;   a pressure passage formed in the fixed scroll, wherein the back pressure passage provides for communication between the pair of compression chambers and the back pressure chamber; and   an injection passage formed in the fixed scroll, wherein the injection passage receives refrigerant from an intermediate portion of a refrigerating cycle and injects the received refrigerant back into the pair of compression chambers.   
   
   
       16 . The compressor of  claim 15 , wherein the injection passage is closer to a discharge side of the pair of compression chambers than the back pressure passage is. 
   
   
       17 . The compressor of  claim 15 , wherein an angle between the back pressure passage and the injection passage is greater than approximately 30°. 
   
   
       18 . The compressor of  claim 15 , wherein a diameter of the injection passage is greater than or equal to a diameter of the back pressure passage. 
   
   
       19 . The compressor of  claim 18 , wherein a diameter of the injection passage is less than a thickness of the orbiting wraps. 
   
   
       20 . A refrigerating apparatus, comprising:
 a compressor;   a condenser connected to a discharge side of the compressor;   an expansion apparatus connected to the condenser;   an evaporator connected to the expansion apparatus and to a suction side of the compressor;   a valve positioned between the condenser and the expansion apparatus so as to direct a flow of refrigerant therethrough; and   a bypass pipe connected to the valve and to the compressor, wherein the valve directs a portion of refrigerant from the condenser through the bypass pipe and back into the compressor.   
   
   
       21 . The apparatus of  claim 20 , further comprising a heat exchanger provided at the bypass pipe, wherein the heat exchanger is configured to perform a re-heat-exchange process with the condenser. 
   
   
       22 . The apparatus of  claim 20 , further comprising an injection passage that connects the bypass pipe to the compressor, wherein the bypass pipe is closer to a discharge side of a compression chamber of the compressor than to a back pressure passage of the compressor. 
   
   
       23 . The apparatus of  claim 22 , wherein an angle formed between the injection passage and the back pressure passage is greater than approximately 30°. 
   
   
       24 . The apparatus of  claim 22 , wherein a diameter of the injection passage is greater than or equal to that of the back pressure passage, and less than a thickness of an orbiting scroll wrap of the compressor.