Sealed Scroll Compressor for Helium

Abstract

A sealed scroll compressor for helium having a stationary scroll, an orbiting scroll, and an oil-injection mechanism. The oil-injection mechanism has an oil-injection pipe arranged to pass through a sealed container and connected to an oil-injection port, and the opening of the oil-injection port is arranged at a bottom surface of a groove between ridges formed with the scroll wrap of the stationary scroll in such a manner that a first range of the orbital angle of the orbiting scroll is approximately identical to a second range of the orbital angle of the orbiting scroll, where the oil-injection port is connected to the outer compression chamber while the orbital angle of the orbiting scroll is in the first range, and is connected to the inner compression chamber while the orbital angle of the orbiting scroll is in the second range.

1 . A sealed scroll compressor for helium, comprising:
 a sealed container;   a stationary scroll being contained in the sealed container and having an end plate and a scroll wrap;   an oil-injection port having an opening and being arranged in the end plate of the stationary scroll;   an oil-injection mechanism having an oil-injection pipe which is arranged to pass through the sealed container and connected to the oil-injection port; and   an orbiting scroll contained in the sealed container and interleaved with the stationary scroll to form an outer compression chamber and an inner compression chamber which realize an asymmetric-wrap type compression chambers;   wherein the opening of the oil-injection port is arranged at a bottom surface of a groove between ridges formed with the scroll wrap of the stationary scroll in such a manner that a first range of an orbital angle of the orbiting scroll is approximately identical to a second range of the orbital angle of the orbiting scroll, and the oil-injection port is connected to the outer compression chamber while the orbital angle of the orbiting scroll is in the first range, and is connected to the inner compression chamber while the orbital angle of the orbiting scroll is in the second range.   
     
     
         2 . The sealed scroll compressor according to  claim 1 , wherein a center of the opening is displaced outward from a center of the bottom surface. 
     
     
         3 . The sealed scroll compressor according to  claim 1 , wherein the opening has a shape elongated in a radial direction of the stationary scroll. 
     
     
         4 . The sealed scroll compressor according to  claim 1 , wherein each of the first range and the second range has a width of approximately 200 to 230 degrees. 
     
     
         5 . The sealed scroll compressor according to  claim 1 , wherein a center of the opening is located at a position displaced from an end of the scroll wrap of the stationary scroll toward an inner end of the scroll wrap of the stationary scroll along the scroll wrap of the stationary scroll by a scroll wrap angle of approximately 1.5 π to 2 π rad, where it is the circle ratio. 
     
     
         6 . A sealed scroll compressor for helium, comprising:
 a sealed container;   a stationary scroll being contained in the sealed container and having an end plate and a scroll wrap;   an oil-injection port having an opening and being arranged in the end plate of the stationary scroll;   an oil-injection mechanism having an oil-injection pipe which is arranged to pass through the sealed container and connected to the oil-injection port; and   an orbiting scroll contained in the sealed container and interleaved with the stationary scroll to form an outer compression chamber and an inner compression chamber which realize an asymmetric-wrap type compression chambers;   wherein the opening of the oil-injection port is arranged at a bottom surface of a groove between ridges formed with the wrap of the stationary scroll in such a manner that a first range θ 1  of an orbital angle of the orbiting scroll, a second range θ 2  of the orbital angle of the orbiting scroll, a first stroke volume Vth 1  in the outer compression chamber, and a second stroke volume Vth 2  in the inner compression chamber satisfy a relationship,
   θ 1 /θ 2 ≈Vth1/Vth2.
 
   
     
     
         7 . The sealed scroll compressor according to  claim 6 , wherein a center of the opening is displaced outward from a center of the bottom surface. 
     
     
         8 . The sealed scroll compressor according to  claim 6 , wherein the opening has a shape elongated in a radial direction of the stationary scroll. 
     
     
         9 . The sealed scroll compressor according to  claim 6 , wherein a center of the opening is located at a position displaced from an end of the scroll wrap of the stationary scroll toward an inner end of the scroll wrap of the stationary scroll along the scroll wrap of the stationary scroll by a scroll wrap angle of approximately 1.5 π to 2 π rad, where n is the circle ratio.