US5066197A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hydrodynamic bearing protection system and method
Assignee: Sundstrand Corp
•
Filing: 1990-07-10
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Granted: 1991-11-19
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Expires: 2010-07-10
Abstract
Abstract A protection system for a rotatable element (20) which is rotatably supported by hydrodynamic bearings (22, 24) pressurized with a lubricating fluid provided from a pressure source (26 and/or 34) with the fluid being subject to a change in state from liquid to vapor when heat from the bearings during rotation of the rotatable element is absorbed by the pressurized fluid during supporting of the rotatable element in accordance with the invention includes a pressure sensor (302) in fluid communication with fluid flowing from the hydrodynamic bearings for producing a pressure signal representative of pressure of the fluid flowing from the bearings; a temperature sensor (304) in fluid communication with the fluid flowing from the hydrodynamic bearings from producing a temperature signal representative of temperature of the fluid flowing from the bearings; a prime mover (17) for driving the rotatable element with a variable rotational velocity; and a controller (400), responsive to the pressure and temperature signals, for controlling the rotational velocity of the prime mover as a function of the pressure and temperature signals to prevent the change in state of the fluid flowing from the bearings from liquid to vapor.
Inventors
- 👤 John M. Champagne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:07
CPC Classifications
F; F16; F16C; F16C37/00; F16C37/002; F04; F04D; F04D27/00; F04D27/02; F04D27/0261; F04D27/0292; F04D29/00; F04D29/05; F04D29/056; F04D29/057; F16C32/00; F16C32/06; F16C32/0629; F16C32/064; F16C33/00; F16C33/02; F16C33/04; F16C33/06; F16C33/10; F25; F25B; F25B1/00; F25B31/00; F25B31/002; F25B9/00; F25B9/002; F25B9/006
Claims Analysis
Total Claims: 29
Claim 1
Independent Claim
174 words
A protection system for a rotatable element which is rotatably supported by hydrodynamic bearings pressurized with a lubricating fluid provided from a pressure source with the fluid being subject to a change in state from liquid to vapor when heat from the bearings during rotation of the rotatable element is absorbed by the pressurized fluid during supporting of the rotatable element comprising: a pressure sensor in fluid communication with fluid flowing from the hydrodynamic bearings for producing a pressure signal representative of pressure of the fluid flowing from the bearings; a temperature sensor in fluid communication with fluid flowing from the hydrodynamic bearings for producing a temperature signal representative of temperature of the fluid flowing from the bearings; a prime mover for driving the rotatable element with a variable rotational velocity; and a controller, responsive to the pressure and temperature signals, for controlling the velocity of the prime mover as a function the pressure and temperature signals to prevent the change in state of the fluid flowing through the bearings from liquid to vapor.
Claim 2
Dependent Claim
174 words
A protection system for a rotatable element which is rotatably supported by hydrodynamic bearings pressurized with a lubricating fluid provided from a pressure source with the fluid being subject to a change in state from liquid to vapor when heat from the bearings during rotation of the rotatable element is absorbed by the pressurized fluid during supporting of the rotatable element comprising: a pressure sensor in fluid communication with fluid flowing from the hydrodynamic bearings for producing a pressure signal representative of pressure of the fluid flowing from the bearings; a temperature sensor in fluid communication with fluid flowing from the hydrodynamic bearings for producing a temperature signal representative of temperature of the fluid flowing from the bearings; a prime mover for driving the rotatable element with a variable rotational velocity; and a controller, responsive to the pressure and temperature signals, for controlling the velocity of the prime mover as a function the pressure and temperature signals to prevent the change in state of the fluid flowing through the bearings from liquid to vapor.
Claim 3
Dependent Claim
25 words
A protection system in accordance with claim 1 wherein: the rotatable element is a rotor of a centrifugal compressor; and the fluid is a refrigerant.
Claim 4
Dependent Claim
15 words
A protection system in accordance with claim 2 wherein: the refrigerant is a non-azeotropic binary
Claim 5
Dependent Claim
111 words
A protection system in accordance with claim 3 wherein: the controller controls the rotational velocity by calculating a bubblepoint temperature of the refrigerant as a function of the pressure of the refrigerant flowing from the hydrodynamic bearings, calculating a difference between the bubblepoint temperature and the temperature of the refrigerant flowing from the bearings, calculating a control value equal to a difference between the difference between the difference between the bubblepoint temperature and the temperature of the refrigerant flowing from the bearings and a set reference temperature and causes the prime mover to reduce the rotational velocity of the rotor when the control value is less than a set reference temperature.
Claim 6
Dependent Claim
34 words
A protection system in accordance with claim 4 wherein: the prime mover is an electric motor which is turned off by the controller when the control value is less than the set reference temperature.
Claim 7
Dependent Claim
37 words
A protection system in accordance with claim 4 wherein: the prime mover is an electric motor; and the reduction of the rotational velocity by the electric motor is a function of a magnitude of the control value.
Claim 8
Dependent Claim
62 words
A protection system in accordance with claim 6 wherein: the reduction of the rotational velocity by the electric motor is a linear function of the magnitude of the control value with the rotational velocity being zero when the control value is zero or negative and not being reduced when the control value is equal to or greater than the set reference temperature.
Claim 9
Dependent Claim
62 words
A protection system in accordance with claim 6 wherein: the reduction of the rotational velocity by the prime mover is a non-linear function of the magnitude of the control value with the rotational velocity being zero when the control value is zero or negative and not being reduced where the control value is equal to or greater than the set reference temperature.
Claim 10
Dependent Claim
109 words
A protection system in accordance with claim 2 wherein: the controller controls the rotational velocity by calculating a bubblepoint temperature of the refrigerant as a function of the pressure of the refrigerant flowing from the hydrodynamic bearings, calculating a difference between the bubblepoint temperature and the temperature of the refrigerant flowing from the bearings, calculating a control value equal to a difference between the difference between the bubblepoint temperature and the temperature of the the refrigerant flowing from the bearings and a set reference temperature and causes the prime mover to reduce the rotational velocity of the rotor when the control value is less than a set reference temperature.
Claim 11
Dependent Claim
34 words
A protection system in accordance with claim 9 wherein: the prime mover is an electric motor which is turned off by the controller when the control value is less than the set reference temperature.
Claim 12
Dependent Claim
37 words
A protection system in accordance with claim 9 wherein: the prime mover is an electric motor; and the reduction of the rotational velocity by the electric motor is a function of a magnitude of the control value.
Claim 13
Dependent Claim
62 words
A protection system in accordance with claim 11 wherein: the reduction of the rotational velocity by the electric motor is a linear function of the magnitude of the control value with the rotational velocity being zero when the control value is zero or negative and not being reduced when the control value is equal to or greater than the set reference temperature.
Claim 14
Dependent Claim
62 words
A protection system in accordance with claim 11 wherein: the reduction of the rotational velocity by the prime mover is a non-linear function of the magnitude of the control value with the rotational velocity being zero when the control value is zero or negative and not being reduced when the control value is equal to or greater than the set reference temperature.
Claim 15
Independent Claim
124 words
A method of protecting a rotatable element which is rotatably supported by hydrodynamic bearings pressurized with a lubricating fluid provided from a pressure source with the fluid being subject to a change in state from liquid to vapor when heat from the bearings during rotation of the rotatable element is absorbed by the pressurized fluid during supporting of the rotatable element comprising: sensing pressure of the fluid flowing from the hydrodynamic bearings; sensing temperature of the fluid flowing from the hydrodynamic bearings; and controlling a rotational velocity of a variable velocity prime mover which drives the rotatable element as a function of the sensed pressure and temperature to prevent the change in state of the fluid flowing through the bearings from liquid to vapor.
Claim 16
Independent Claim
124 words
A method of protecting a rotatable element which is rotatably supported by hydrodynamic bearings pressurized with a lubricating fluid provided from a pressure source with the fluid being subject to a change in state from liquid to vapor when heat from the bearings during rotation of the rotatable element is absorbed by the pressurized fluid during supporting of the rotatable element comprising: sensing pressure of the fluid flowing from the hydrodynamic bearings; sensing temperature of the fluid flowing from the hydrodynamic bearings; and controlling a rotational velocity of a variable velocity prime mover which drives the rotatable element as a function of the sensed pressure and temperature to prevent the change in state of the fluid flowing through the bearings from liquid to vapor.
Claim 17
Dependent Claim
24 words
A method in accordance with claim 14 wherein: the rotatable element is a rotor of a centrifugal compressor; and the fluid is a refrigerant.
Claim 18
Dependent Claim
15 words
A method in accordance with claim 15 wherein: the refrigerant is a non-azeotropic binary refrigerant.
Claim 19
Dependent Claim
94 words
A method in accordance with claim 16 further comprising: calculating a bubblepoint temperature of the refrigerant as a function of the pressure of the refrigerant flowing from the bearings; calculating a difference between the bubblepoint temperature and the temperature of the refrigerant flowing from the bearings; calculating a control value equal to a difference between the difference between bubblepoint temperature and the temperature of the refrigerant flowing from the bearings and a set reference temperature; and reducing the rotational velocity of the rotor when the control value is less than a set reference temperature.
Claim 20
Dependent Claim
30 words
A method in accordance with claim 17 wherein: the prime mover is an electric motor which is turned off when the control value is less than the set reference temperature.
Claim 21
Dependent Claim
36 words
A method in accordance with claim 17 wherein: the prime mover is an electric motor; and the reduction of the rotational velocity by the electric motor is a function of a magnitude of the control value.
Claim 22
Dependent Claim
60 words
A method in accordance with claim 19 wherein: the reduction of the rotational velocity by the electric motor is a linear function of the magnitude of the control value with the rotational velocity being zero when the control value is zero or negative and not being reduced when the control value is equal to or greater than the set reference.
Claim 23
Dependent Claim
60 words
A method in accordance with claim 19 wherein: the reduction of the rotational velocity by the prime mover is a non-linear function of the magnitude of the control value with the rotational velocity being zero when the control value is zero or negative and not being reduced when the control value is equal to or greater than the set reference.
Claim 24
Dependent Claim
140 words
A protection system for a rotatable element which is rotatably driven by a prime mover and rotatably supported by hydrodynamic bearings pressurized with a lubricating fluid provided from a pressure source with the fluid being subject to a change in state from liquid to vapor when heat from the bearings during rotation of the rotatable element is absorbed by the pressurized fluid supporting the rotatable element comprising: at least one sensor for sensing at least one physical characteristic of the lubricating fluid flowing from the hydrodynamic bearings; and a controller, responsive to the at least one sensed physical characteristic of the lubricating fluid, for controlling the rotational velocity of the prime mover as a function of the at least one sensed physical characteristic to prevent the change in state of the fluid flowing through the bearings from liquid to vapor.
Claim 25
Dependent Claim
140 words
A protection system for a rotatable element which is rotatably driven by a prime mover and rotatably supported by hydrodynamic bearings pressurized with a lubricating fluid provided from a pressure source with the fluid being subject to a change in state from liquid to vapor when heat from the bearings during rotation of the rotatable element is absorbed by the pressurized fluid supporting the rotatable element comprising: at least one sensor for sensing at least one physical characteristic of the lubricating fluid flowing from the hydrodynamic bearings; and a controller, responsive to the at least one sensed physical characteristic of the lubricating fluid, for controlling the rotational velocity of the prime mover as a function of the at least one sensed physical characteristic to prevent the change in state of the fluid flowing through the bearings from liquid to vapor.
Claim 26
Dependent Claim
60 words
A protection system in accordance with claim 22 wherein: the at least one sensor is a pressure sensor and a temperature sensor; the prime mover is an electric motor; the lubricating fluid is a refrigerant; the rotatable element is a rotor of a centrifugal compressor; and controlled as a function of the bubblepoint of the refrigerant flowing from the bearings.
Claim 27
Independent Claim
118 words
A method of protecting a rotatable element which is rotatably supported by hydrodynamic bearings pressurized with a lubricating fluid provided from a pressure source with the fluid being subject to a change in state from liquid to vapor when heat from the bearings during rotation of the rotatable element is absorbed by the pressurized fluid during supporting of the rotatable element comprising: sensing at least one physical characteristic of the fluid flowing from the hydrodynamic bearings; and controlling a rotational velocity of a prime mover which drives the rotatable element as a function of the at least one physical characteristic sensed to prevent the change in state of the fluid flowing through the bearings from liquid to vapor.
Claim 28
Independent Claim
118 words
A method of protecting a rotatable element which is rotatably supported by hydrodynamic bearings pressurized with a lubricating fluid provided from a pressure source with the fluid being subject to a change in state from liquid to vapor when heat from the bearings during rotation of the rotatable element is absorbed by the pressurized fluid during supporting of the rotatable element comprising: sensing at least one physical characteristic of the fluid flowing from the hydrodynamic bearings; and controlling a rotational velocity of a prime mover which drives the rotatable element as a function of the at least one physical characteristic sensed to prevent the change in state of the fluid flowing through the bearings from liquid to vapor.
Claim 29
Dependent Claim
49 words
A method in accordance with claim 24 wherein: the rotatable element is a rotor of a centrifugal compressor; the fluid is a refrigerant; the prime mover is an electric motor; and the at least one sensed physical characteristic is pressure and temperature of the refrigerant flowing from the bearings.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-11-18 | 1995-05-20 | 1995-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-11-18 | 1999-05-20 | 1999-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-11-18 | 2003-05-20 | 2003-11-19 | $7700.00 | Window Closed / Lapsed |