Screw compressor with male and female rotors

Patent metadata

Field	Value
Publication number	US-11725658-B2
Application number	US-201716322448-A
Country	US
Kind code	B2
Filing date	Aug 1, 2017
Priority date	Aug 2, 2016
Publication date	Aug 15, 2023
Grant date	Aug 15, 2023

Abstract

The present application provides a screw compressor that comprises a first male rotor and a second male rotor, each of the first male rotor and the second male rotor having convex-helical teeth, the first male rotor and the second male rotor being rigidly connected together; a first female rotor and a second female rotor, each of the first female rotor and the second female rotor having concave-helical teeth, the first female rotor being arranged separately from and opposite to each other; wherein the convex-helical teeth of the first male rotor are engaged with the concave-helical teeth of the first female rotor, and the convex-helical teeth of the second male rotor are engaged with the concave-helical teeth of the second female rotor. The male rotors in the screw compressor are symmetrically so that the axial force exerted on the first male rotor counteract with the axial force exerted on the second male rotor.

First claim

The invention claimed is:

1. A screw compressor, comprising:
a first male rotor and a second male rotor, each of the first male rotor and the second male rotor having two ends and convex-helical teeth, the first male rotor and the second male rotor being rigidly connected together, wherein each end of the first male rotor and the second male rotor is mounted on a respective roller bearing; and
a first female rotor and a second female rotor, each of the first female rotor and the second female rotor having two additional ends and concave-helical teeth, the first female rotor and the second female rotor being arranged separately from and opposite to each other, wherein each additional end of the first female rotor and the second female rotor is mounted on a respective additional roller bearing, and wherein one of the two additional ends of each of the first female rotor and the second female rotor is mounted on a respective thrust bearing;
wherein the convex-helical teeth of the first male rotor are engaged with the concave-helical teeth of the first female rotor, and the convex-helical teeth of the second male rotor are engaged with the concave-helical teeth of the second female rotor.

2. The screw compressor according to claim 1 , wherein:
a first compressing channel is formed between the first male rotor and the first female rotor, the first compressing channel has a first inlet and a first outlet, a first stream of medium flows through the first compressing channel in a first flow direction from the first inlet to the first outlet; and
a second compressing channel is formed between the second male rotor and the second female rotor, the second compressing channel has a second inlet and a second outlet, a second stream of medium flows through the second compressing channel in a second flow direction from the second inlet to the second outlet.

3. The screw compressor according to claim 2 , wherein:
the first stream of medium generates a first axial force that is exerted on the first male rotor when the first stream of medium is being compressed in the first compressing channel;
the second stream of medium generates a second axial force that is exerted on the second male rotor when the second stream of medium is being compressed in the second compressing channel; and
the first axial force and the second axial force are opposite to each other.

4. The screw compressor according to claim 2 , wherein the first stream of medium and the second stream of medium flow towards or flow away from each other.

5. The screw compressor according to claim 4 , wherein the medium is refrigerant.

6. The screw compressor according to claim 2 , wherein the first stream of medium and the second stream of medium are introduced from an evaporator and sent to a condenser after being compressed by the screw compressor.

7. The screw compressor according to claim 1 , wherein the first male rotor and the second male rotor are rigidly connected together by a rigid shaft coupling or rigid union joint, by welding, or by being made as one piece.

8. The screw compressor according to claim 1 , wherein when the first male rotor and the second male rotor rotate in a first rotation direction, the first female rotor and the second female rotor are driven by the first male rotor and the second male rotor to rotate in a second rotation direction, the first rotation direction is opposite to the second rotation direction.

9. The screw compressor according to claim 1 , wherein the first male rotor, the second male rotor, the first female rotor and the second female rotor are enclosed in a housing in a sealed condition.

10. The screw compressor according to claim 1 , further comprising: a motor that is amounted on a shaft between the first male rotor and the second male rotor.

11. A refrigeration air-conditioning unit, comprising:
a screw compressor, comprising:
a first male rotor and a second male rotor, each of the first male rotor and the second male rotor having convex-helical teeth, the first male rotor and the second male rotor being rigidly connected together; and
a first female rotor and a second female rotor, each of the first female rotor and the second female rotor having two ends and concave-helical teeth, the first female rotor and the second female rotor being arranged separately from and opposite to each other, wherein each end of the first female rotor and the second female rotor is mounted on a respective roller bearing, wherein one of the two ends of each of the first female rotor and the second female rotor is mounted on a respective thrust bearing, and wherein only the first female rotor and the second female rotor are mounted on thrust bearings;
wherein the convex-helical teeth of the first male rotor are engaged with the concave-helical teeth of the first female rotor, and the convex-helical teeth of the second male rotor are engaged with the concave-helical teeth of the second female rotor.

12. The refrigeration air-conditioning unit according to claim 11 , wherein the screw compressor comprises:
a first compressing channel is formed between the first male rotor and the first female rotor, the first compressing channel has a first inlet and a first outlet, a first stream of medium flows through the first compressing channel in a first flow direction from the first inlet to the first outlet; and
a second compressing channel is formed between the second male rotor and the second female rotor, the second compressing channel has a second inlet and a second outlet, a second stream of medium flows through the second compressing channel in a second flow direction from the second inlet to the second outlet.

13. The refrigeration air-conditioning unit according to claim 12 , wherein the first male rotor and the second male rotor are rigidly connected together via a shaft.

14. The refrigeration air-conditioning unit according to claim 13 , comprising:
a motor mounted on the shaft extending between the first male rotor and the second male rotor.

15. The refrigeration air-conditioning unit according to claim 12 , comprising:
an evaporator; and
a condenser,
wherein the first stream of medium and the second stream of medium are introduced from the evaporator and sent to the condenser after being compressed by the screw compressor, and wherein the first stream of medium and the second stream of medium are refrigerant.

16. The refrigeration air-conditioning unit according to claim 15 , wherein the first stream of medium and the second stream of medium flow through the screw compressor away from each other.

17. The refrigeration air-conditioning unit according to claim 15 , wherein the first stream of medium and the second stream of medium flow through the screw compressor towards each other.

Assignees

• Johnson Controls Air Conditioning And Refrigeration Wuxi Co Ltd
• Johnson Controls Tech Co
• Johnson Controls Tyco IP Holdings LLP

Inventors

• Li Haijun

Classifications

• F04C18/16 Primary

  with helical teeth, e.g. chevron-shaped, screw type {(for non-parallel axes of movement F04C18/48)} · CPC title

• F04C18/084

  Toothed wheels · CPC title

• F04C18/20

  with dissimilar tooth forms (F04C18/16 takes precedence) · CPC title

• F01C21/08

  Rotary pistons (reciprocating pistons in general F16J) · CPC title

• F04C29/0021

  Systems for the equilibration of forces acting on the pump (interstice adjustment other than by fluid pressure F01C21/102) · CPC title