Scroll compressor including back pressure communication unit

A scroll compressor, comprising:

• a casing;
• a rotating shaft comprising a first eccentric portion and a second eccentric portion spaced apart from each other in an axial direction;
• a first compression unit having a first orbiting scroll coupled to the first eccentric portion of the rotating shaft to perform an orbiting motion, and a first fixed scroll engaged with the first orbiting scroll to define a first compression chamber;
• a second compression unit having a second orbiting scroll coupled to the second eccentric portion of the rotating shaft to perform an orbiting motion, and a second fixed scroll engaged with the second orbiting scroll to define a second compression chamber;
• a main frame having a shaft accommodation portion disposed therein such that the rotating shaft penetrates through the shaft accommodation portion, and located between the first compression unit and the second compression unit;
• a first back pressure chamber disposed between the first orbiting scroll and a first side surface of the main frame to support the first orbiting scroll toward the first fixed scroll;
• and
• a second back pressure chamber disposed between the second orbiting scroll and a second side surface of the main frame to support the second orbiting scroll toward the second fixed scroll, wherein the main frame comprises at least one back pressure communication unit configured to communicate between the first back pressure chamber and the second back pressure chamber, wherein the at least one back pressure communication unit comprises a back pressure communication hole configured to communicate between the first back pressure chamber and the second back pressure chamber, and a pin member inserted into the back pressure communication hole, and wherein a sectional area of the pin member is disposed to be smaller than a sectional area of the back pressure communication hole.

A scroll compressor, comprising:

• a casing;
• a rotating shaft comprising a first eccentric portion and a second eccentric portion spaced apart from each other in an axial direction;
• a first compression unit having a first orbiting scroll coupled to the first eccentric portion of the rotating shaft to perform an orbiting motion, and a first fixed scroll engaged with the first orbiting scroll to define a first compression chamber;
• a second compression unit having a second orbiting scroll coupled to the second eccentric portion of the rotating shaft to perform an orbiting motion, and a second fixed scroll engaged with the second orbiting scroll to define a second compression chamber;
• a main frame having a shaft accommodation portion disposed therein such that the rotating shaft penetrates through the shaft accommodation portion, and located between the first compression unit and the second compression unit;
• a first back pressure chamber disposed between the first orbiting scroll and a first side surface of the main frame to support the first orbiting scroll toward the first fixed scroll;
• and
• a second back pressure chamber disposed between the second orbiting scroll and a second side surface of the main frame to support the second orbiting scroll toward the second fixed scroll, wherein the main frame comprises at least one back pressure communication unit configured to communicate between the first back pressure chamber and the second back pressure chamber, wherein the at least one back pressure communication unit comprises a back pressure communication hole configured to communicate between the first back pressure chamber and the second back pressure chamber, and a valve member configured to open or close the back pressure communication hole, wherein a valve accommodating hole is further disposed in the main frame in a direction intersecting with the back pressure communication hole, and wherein the valve member is slidably inserted into the valve accommodating hole to open or close the back pressure communication hole.