Screw compressor

Patent metadata

Field	Value
Publication number	US-9828998-B2
Application number	US-201615289869-A
Country	US
Kind code	B2
Filing date	Oct 10, 2016
Priority date	Oct 17, 2012
Publication date	Nov 28, 2017
Grant date	Nov 28, 2017

Abstract

A screw compressor includes a housing having an inlet for receiving gas to be compressed by the compressor and an outlet for discharging pressurized compressed gas. A pair of meshing threaded rotors, each rotor having an axis and being rotatably received in the housing, each rotor having a first end near the inlet and a second end near the outlet. A bearing rotatably carrying each rotor about its axis and positioned near the first end and the second end of each rotor. A conduit formed in the housing in selectable fluid communication with at least one bearing and a force generating source from a pressurized fluid source, the force generating source selectably providing a force in a radial direction relative to the axis of the at least one bearing.

First claim

The invention claimed is:

1. A system, comprising:
a housing;
a first shaft rotatable with respect to the housing, disposed within the housing, and having a first rotor axis extending axially within the first shaft;
a first bearing disposed circumferentially about the first shaft at a first axial position along the first rotor axis;
a second bearing disposed circumferentially about the first shaft at a second axial position along the first rotor axis, wherein the second axial position is adjacent to the first axial position; and
a force generating source configured to selectively exert a first force in a radial direction on a first outer surface of the first bearing based on a desired share, between the first and second bearings, of an operating load of the system, wherein the first bearing is configured to respond to the first force by moving radially relative to the second bearing.

2. The system of claim 1 , wherein the force generating source comprises an actuator driven by an electric motor.

3. The system of claim 1 , wherein the force generating source utilizes a pressurized fluid to exert the first force.

4. The system of claim 1 , comprising:
a second shaft rotatable with respect to the housing, disposed within the housing, and having a second rotor axis extending axially within the second shaft;
a third bearing disposed circumferentially about the second shaft at a third axial position along the second rotor axis; and
a fourth bearing disposed circumferentially about the second shaft at a fourth axial position along the second rotor axis, wherein the fourth axial position is adjacent to the third axial position, and wherein the force generating source, or an additional force generating source, is configured to selectively exert a second force in the radial direction on a third outer surface of the third bearing based on a desired share, between the third and fourth bearings, of the operating load of the system, wherein the third bearing is configured to respond to the second force by moving radially relative to the fourth bearing.

5. The system of claim 1 , comprising a compressor having the housing, the shaft, and the first and second bearings.

6. The system of claim 5 , wherein the compressor comprises a screw compressor, a reciprocating compressor, a scroll compressor, or a rotary compressor.

7. The system of claim 5 , comprising a controller configured to determine a magnitude of the first force in the radial direction based at least in part on an operating parameter of the compressor, and to control the force generating source such that the force generating source exerts the magnitude of the first force in the radial direction.

8. The system of claim 1 , comprising:
a passageway extending radially through the housing and configured to enable exertion of the first force by the force generating source; and
an O-ring extending circumferentially about the first bearing proximate to the passageway and between the first outer surface of the first bearing and an inner surface of the housing.

9. The system of claim 8 , wherein the first bearing, the housing, or both comprise a groove or a channel configured to receive the O-ring therein.

10. The system of claim 8 , wherein the O-ring extends less than 360degrees circumferentially about the first bearing, and wherein the system comprises a space between the first bearing and the inner surface of the housing opposite the O-ring.

11. The system of claim 1 , wherein the system comprises an HVAC system.

12. The system of claim 1 , wherein the force generating source comprises a selectively moveable piston, a pressurized fluid source, a valve adjustable by pressurized fluid from a pressurized fluid source, a fastener adjustable by a spring, a hand pump, a central air pressure system, a pressurized nitrogen bottle, a discharge pressure from the compressor or another compressor, an intermediate pressure from the compressor or the other compressor, a pressurized oil from an oil separator, or a combination thereof.

13. A control system of a compressor, comprising:
a controller;
a sensor communicatively coupled with the controller, wherein the sensor is configured to detect an operating parameter of the compressor, and wherein the sensor is configured to communicate data indicative of the operating parameter to the controller; and
a force generating source configured to exert a radial force on a first bearing element of a pair of bearing elements of the compressor, wherein the controller is configured to determine a first magnitude of the radial force based on the data indicative of the operating parameter, and wherein the controller is configured to instruct the force generating source to exert the first magnitude of the radial force on the first bearing element, such that the first bearing element is configured to move radially relative to a second bearing element of the pair of bearing elements in response to the first magnitude of the radial force.

14. The control system of claim 13 , wherein the operating parameter comprises a suction pressure magnitude, a discharge pressure magnitude, or a position of a slide stop of the compressor.

15. The control system of claim 13 , wherein the force generating source comprises a pressurized fluid and a flow control device communicatively coupled with the controller, and wherein the controller is configured to control the flow control device to enable the first magnitude of the radial force.

16. The control system of claim 13 , wherein the force generating source comprises a piston, a spring, or an electrically driven motor.

17. A compressor, comprising:
a housing;
a first rotor rotatable with respect to the housing and extending along a first rotor axis, wherein the first rotor comprises a first rotor body extending along the first rotor axis, a first rotor end near an inlet of the compressor, and a second rotor end near an outlet of the compressor opposite to the inlet of the compressor;
a first bearing disposed circumferentially about the first rotor body at the first or the second rotor end;
a second bearing disposed circumferentially about the first rotor body at the first or the second rotor end, and adjacent to the first bearing;
a controller configured to determine, based at least in part on a desired share between the first and second bearings of a compressor operating load, a first magnitude of a radial force to be exerted on a first outer surface of the first bearing; and
a force generating source configured to, upon instruction by the controller, selectively exert the first magnitude of the radial force, wherein the compressor is configured to route the first magnitude of the radial force on the first outer surface of the first bearing, and wherein the first bearing is configured to move radially relative to the second bearing in response to the first magnitude of the radial force.

18. The compressor of claim 17 , wherein a sensor communicatively coupled with the controller is configured to detect the compressor operating load, or an operating parameter indicative thereof, and wherein the sensor is configured to communicate data indicative of the compressor operating load, or the operating parameter thereof, to the controller.

19. The compressor of claim 18 , wherein the controller determines the first magnitude of the radial force based at least in part on the data indicative of the compressor operating load, or the operating parameter thereof.

20. The compressor of claim 17 , comprising:
a second rotor

Assignees

• Johnson Controls Tech Co

Inventors

• Tychsen Holger

Classifications

• F04C29/0021 Primary

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

• F04C18/0215

  where only one member is moving · CPC title

• F04C2240/10

  Stators · CPC title

• F04C18/16

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

• F04B35/04

  the means being electric · CPC title