Compressor having capacity modulation system

1. A compressor comprising:

a housing;

a non-orbiting scroll member supported within said housing and including a first end plate and a first spiral wrap extending from said first end plate;

an orbiting scroll member supported within said housing and including a second end plate having a second spiral wrap extending therefrom and meshingly engaged with said first spiral wrap to form a series of compression pockets;

a first porting extending through said first end plate and located radially outward relative to a radially outer surface of said first spiral wrap at least five hundred and forty degrees inward along said first spiral wrap from an outer end thereof, said first porting being in communication with a first of said compression pockets during a portion of a compression cycle of said orbiting and non-orbiting scroll members, said first and second spiral wraps abutting one another to define first modulated capacity pockets when said orbiting scroll member is in a first position, said first modulated capacity pockets including a set of radially outermost compression pockets located radially inward relative to said first porting and isolated from communication with said first porting during an entirety of said compression cycle, said first porting aligned with said second spiral wrap at a location radially outward from and directly adjacent said first modulated capacity pockets when said orbiting scroll member is in the first position; and

additional porting extending through said first end plate and in communication with each of said compression pockets located radially outward relative to said first modulated capacity pockets when said orbiting scroll member is in the first position.

2. The compressor of claim 1 , wherein said first porting has an angular extent of at least twenty degrees.

3. The compressor of claim 1 , wherein a first angular position defined by said abutting of said first and second spiral wraps defines a starting location of said first porting.

4. The compressor of claim 1 , further comprising a second porting extending through said first end plate and located radially inward relative to a radially inner surface of said first spiral wrap at least three hundred and sixty degrees inward along said first spiral from said outer end thereof, said second porting being in communication with a second of said compression pockets during a portion of said compression cycle, said first and second spiral wraps abutting one another to define second modulated capacity pockets when said orbiting scroll member is in a second position subsequent to the first position, said second modulated capacity pockets including a set of radially outermost compression pockets located radially inward relative to said first and second porting and isolated from communication with said first and second porting during an entirety of said compression cycle.

5. The compressor of claim 4 , wherein said second porting has an angular extent of at least twenty degrees.

6. The compressor of claim 4 , wherein said second porting is aligned with said second spiral wrap at a location radially outward from and directly adjacent said second set of radially outermost pockets when said orbiting scroll member is in the second position.

7. The compressor of claim 4 , wherein said second porting is in communication with said first modulated capacity pockets when said orbiting scroll member is in the first position.

8. The compressor of claim 4 , wherein said second modulated capacity pockets correspond to said first modulated capacity pockets after displacement of said orbiting scroll member from the first position to the second position.

9. The compressor of claim 4 , wherein said additional porting includes a third porting located radially outward relative to said radially outer surface of said first spiral wrap less than five hundred and forty degrees inward along said first spiral from said outer end thereof.

10. The compressor of claim 9 , wherein said additional porting includes a fourth porting located radially inward relative to said radially inner surface of said first spiral wrap less than three hundred and sixty degrees inward along said first spiral from said outer end thereof.

11. The compressor of claim 1 , wherein a pressure in said first porting is continuously increasing during said compression cycle.

12. The compressor of claim 1 , wherein said second spiral wrap overlies an entirety of said first porting when said orbiting scroll member is in the first position.

13. The compressor of claim 1 , wherein said first porting is isolated from communication with said compression pockets by said second spiral wrap when said orbiting scroll member is in the first position.

14. The compressor of claim 1 , wherein said first porting includes a continuous aperture.

15. The compressor of claim 1 , wherein said porting includes a series of discrete apertures.

16. The compressor of claim 1 , further comprising a valve member in communication with said first porting and said additional porting to selectively provide communication between said compression pockets located radially outward from said first modulated capacity pockets and a bypass location external to said compression pockets.

17. The compressor of claim 16 , wherein said bypass location includes a suction pressure region of the compressor.