Compressor with capacity modulation and variable volume ratio

• US 9,494,157 B2
• Filed: 09/07/2015
• Issued: 11/15/2016
• Est. Priority Date: 11/30/2012
• Status: Active Grant

• Current Assignee: Copeland Corporation LLC (Emerson Electric Company)
• Original Assignee: Emerson Climate Technologies Incorporated (Emerson Electric Company)
• Inventors: Doepker, Roy J.
• Primary Examiner(s): DAVIS, MARY ALICE
• Application Number:
  US14/846,877
• Publication Number:
  US 20160025093A1
• Time in Patent Office: 435 Days
• US Class Current: 1/1
• CPC Class Codes: F04C 18/0215 where only one member is moving
• CPC Class Codes: F04C 18/0261 Details of the ports, e.g. location, number, geometry
• CPC Class Codes: F04C 23/008 Hermetic pumps
• CPC Class Codes: F04C 28/16 using lift valves
• CPC Class Codes: F04C 28/24 characterised by using valves controlling pressure or flow rate, e.g. discharge valves or unloading valvesF04C28/10 takes precedence

Abstract

A compressor is provided and may include a shell assembly defining a suction pressure region and a discharge pressure region. A first scroll member may include a first discharge port and a first modulation port. A second scroll member may include a first variable volume ratio port. A capacity modulation valve assembly may be in fluid communication with the first modulation port and may be displaceable between open and closed positions to selectively provide communication between a first intermediate compression pocket and the suction pressure region via the first modulation port. A variable volume ratio valve assembly may be in fluid communication with the first variable volume ratio port. The variable volume ratio valve assembly may be displaceable between open and closed positions to selectively provide communication between a second intermediate compression pocket and the discharge pressure region via the first variable volume ratio port.

Claims

1. A compressor comprising:

a shell assembly;

a first scroll member disposed within said shell assembly, said first scroll member including a first end plate defining a discharge port and a first port and having a first spiral wrap extending from a first side thereof;

a second scroll member disposed within said shell assembly and including a second end plate defining a second port and having a second spiral wrap extending therefrom and meshingly engaged with said first spiral wrap to form a suction-pressure pocket in fluid communication with a suction-pressure region disposed outside of said first and second spiral wraps, intermediate-pressure pockets, and a discharge-pressure pocket in fluid communication with a discharge-pressure region disposed outside of said first and second spiral wraps, a first of said intermediate-pressure pockets being in fluid communication with said first port and a second of said intermediate-pressure pockets being in fluid communication with said second port;

a motor assembly driving relative orbital motion between said first and second scroll members;

a first valve assembly located within said shell assembly and in fluid communication with said first port, said first valve assembly displaceable between open and closed positions to selectively provide communication between said first intermediate-pressure pocket and said suction-pressure region via said first port; and

a second valve assembly located within said shell assembly and in fluid communication with said second port, said second valve assembly displaceable between open and closed positions to selectively provide communication between said second intermediate-pressure pocket and said discharge-pressure region via said second port.

2. The compressor of claim 1, wherein said first scroll member is a non-orbiting scroll member, and said second scroll member is an orbiting scroll member.

3. The compressor of claim 1, further comprising a floating seal assembly engaging said first scroll member, and wherein said first scroll member is axially displaceable relative to said second scroll member, said floating seal assembly defining a biasing chamber that biases the first scroll member axially toward the second scroll member.

4. The compressor of claim 1, wherein the compressor operates at a full capacity when said first port is closed by said first valve assembly and operates at a reduced capacity relative to the full capacity when said first port is opened by said first valve assembly, said first valve assembly being adapted to cycle between opening and closing of said first port in a pulse width modulated manner to provide a compressor operating capacity between the reduced capacity and the full capacity.

5. The compressor of claim 1, wherein said first valve assembly includes:

a modulation valve ring located axially between a seal assembly and said first end plate and being in sealing engagement with an outer radial surface of an annular hub and said seal assembly to define an axial biasing chamber in fluid communication with a biasing passage in the first end plate, said modulation valve ring being axially displaceable between first and second positions, said modulation valve ring abutting said first end plate and closing said first port when in the first position and being displaced axially relative to said first end plate and opening said first port when in the second position;

a modulation lift ring located axially between said modulation valve ring and said first end plate and being in sealing engagement with said modulation valve ring to define a modulation control chamber; and

a modulation control valve assembly operable in first and second modes and in fluid communication with said modulation control chamber, said modulation control valve assembly controlling an operating pressure within said modulation control chamber and providing a first pressure within said modulation control chamber when operated in the first mode to displace said modulation valve ring to the first position and providing a second pressure within said modulation control chamber greater than the first pressure when operated in the second mode to displace said modulation valve ring to the second position and reduce operating capacity of the compressor.

6. The compressor of claim 5, wherein said modulation valve ring is displaced axially away from said modulation lift ring when said modulation valve ring is displaced from the first position to the second position.

7. The compressor of claim 5, wherein said modulation valve ring includes a first passage extending from said axial biasing chamber to said modulation control valve assembly and a second passage extending from said modulation control chamber to said modulation control valve assembly.

8. The compressor of claim 5, wherein the first pressure is a suction pressure within the compressor and the second pressure is an operating pressure within said axial biasing chamber.

9. The compressor of claim 5, wherein said modulation control valve assembly is in fluid communication with said axial biasing chamber, said modulation control valve assembly providing fluid communication between said modulation control chamber and said axial biasing chamber when operated in the second mode.

10. The compressor of claim 9, wherein said modulation control valve assembly is in fluid communication with said suction-pressure region, said modulation control valve assembly providing fluid communication between said modulation control chamber and said suction-pressure region when operated in the first mode.

11. The compressor of claim 5, wherein said modulation valve ring defines an annular recess having said modulation lift ring disposed therein.

12. The compressor of claim 5, wherein said modulation lift ring abuts said first end plate when said modulation valve ring is in the second position.

13. The compressor of claim 1, further comprising a drive shaft engaged with said second scroll member and driving orbital displacement of said second scroll member relative to said first scroll member, said second end plate defines a second discharge port in communication with said second valve assembly.

14. The compressor of claim 13, wherein said second valve assembly isolates communication between said second intermediate-pressure pocket and said discharge-pressure pocket via said second port when in the closed position and provides communication between said second intermediate-pressure pocket and said discharge-pressure pocket via said second port when in the open position.

15. The compressor of claim 14, wherein a flow path is defined from said second intermediate-pressure pocket to said first discharge port via said second port and via said second discharge port when said second valve assembly is in the open position.

16. The compressor of claim 15, wherein said second scroll member includes a drive hub extending from said second end plate and engaged with said drive shaft, said second valve assembly being located within said drive hub and axially between said drive shaft and said second end plate.

17. The compressor of claim 16, wherein said first valve assembly includes:

a modulation valve ring located axially between a seal assembly and said first end plate and being in sealing engagement with an outer radial surface of an annular hub and said seal assembly to define an axial biasing chamber in fluid communication with a biasing passage in said first end plate, said modulation valve ring being axially displaceable between first and second positions, said modulation valve ring abutting said first end plate and closing said first port when in the first position and being displaced axially relative to said first end plate and opening said first port when in the second position;

a modulation lift ring located axially between said modulation valve ring and said first end plate and being in sealing engagement with said modulation valve ring to define a modulation control chamber; and

a modulation control valve assembly operable in first and second modes and in fluid communication with said modulation control chamber, said modulation control valve assembly controlling an operating pressure within said modulation control chamber and providing a first pressure within said modulation control chamber when operated in the first mode to displace said modulation valve ring to the first position and providing a second pressure within said modulation control chamber greater than the first pressure when operated in the second mode to displace said modulation valve ring to the second position and reduce operating capacity of the compressor.

18. The compressor of claim 17, wherein said modulation valve ring is displaced axially away from said modulation lift ring when said modulation valve ring is displaced from the first position to the second position.

19. The compressor of claim 18, wherein said modulation valve ring includes a first passage extending from said axial biasing chamber to said modulation control valve assembly and a second passage extending from said modulation control chamber to said modulation control valve assembly.

20. The compressor of claim 19, wherein said modulation valve ring defines an annular recess having said modulation lift ring disposed therein.

21. The compressor of claim 1, wherein said shell assembly defines said suction-pressure region and said discharge-pressure region.