US4683111A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas circulator for a nuclear reactor and a method for use thereof
Assignee: John Crane Inc
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Filing: 1986-01-23
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Granted: 1987-07-28
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Expires: 2006-01-23
Abstract
Abstract An improved gas circulator for a gas-cooled nuclear reactor system is disclosed which includes a stator, a rotor having a rotor shaft, and an impeller attached to one end thereof. A radial active magnetic bearing and a radial backup bearing are positioned proximate each end of the rotor shaft. An axial active magnetic bearing is also located between the ends of the rotor shaft, as is an axial backup bearing, with two of the backup bearings enclosed within a sealed chamber that may contain a lubricant, for example, a solid lubricant or a liquid lubricant. Preferably, the gas circulator is installed in a nuclear reactor system with the rotor shaft in a substantially vertical orientation and the sealed chamber near the bottom of the rotor shaft. The lower radical backup bearing and the axial backup bearing are advantageously located within the sealed chamber. The lower radial backup bearing and the axial backup bearing may be spaced apart sufficiently to permit the lower radial backup bearing to provide substantially all radial support for the rotor when the radial active magnetic bearings are deenergized.
Inventors
- 👤 John L. Helm
- 👤 John S. Leonard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:45
CPC Classifications
G; G21; G21K; G21K1/00; G21K1/02; G21K1/04; F; F16; F16C; F16C32/00; F16C32/04; F16C32/0406; F16C32/044; F16C32/0442; F16C32/047; F16C37/00; F16C37/005; F16C39/00; F16C39/02; G21C; G21C15/00; G21C15/24; G21C15/253; H; H02; H02K; H02K5/00; H02K5/04; H02K5/12; H02K7/00; H02K7/08; H02K7/09; H02K9/00; H02K9/14; H02K9/18; F16C2380/00; F16C2380/26; Y; Y02; Y02E; Y02E30/00; Y02E30/30
Claims Analysis
Total Claims: 55
Claim 1
Independent Claim
137 words
A gas circulator for a nuclear reactor, comprising: a stator; a rotor having a rotor shaft with a first end and a second end; an impeller attached to the first end of the rotor shaft; a first radial active magnetic bearing positioned proximate the first end of the rotor shaft; a first radial backup bearing positioned proximate the first end of the rotor shaft; a second radial active magnetic bearing positioned proximate the second end of the rotor shaft; a second radial backup bearing positioned proximate the second end of the rotor shaft; an axial active magnetic bearing positioned between the first and second ends of the rotor shaft; and an axial backup bearing positioned between the first and second ends of the rotor shaft; wherein two of the backup bearings are located within a sealed chamber.
Claim 2
Dependent Claim
137 words
A gas circulator for a nuclear reactor, comprising: a stator; a rotor having a rotor shaft with a first end and a second end; an impeller attached to the first end of the rotor shaft; a first radial active magnetic bearing positioned proximate the first end of the rotor shaft; a first radial backup bearing positioned proximate the first end of the rotor shaft; a second radial active magnetic bearing positioned proximate the second end of the rotor shaft; a second radial backup bearing positioned proximate the second end of the rotor shaft; an axial active magnetic bearing positioned between the first and second ends of the rotor shaft; and an axial backup bearing positioned between the first and second ends of the rotor shaft; wherein two of the backup bearings are located within a sealed chamber.
Claim 3
Dependent Claim
14 words
A gas circulator as defined in claim 1, wherein the chamber contains a lubricant.
Claim 4
Dependent Claim
15 words
A gas circulator as defined in claim 2, wherein the lubricant is a solid lubricant.
Claim 5
Dependent Claim
15 words
A gas circulator as defined in claim 2, wherein the lubricant is a liquid lubricant.
Claim 6
Dependent Claim
24 words
A gas circulator as defined in claim 1, wherein the second radial backup bearing and the axial backup bearing are located within the chamber.
Claim 7
Dependent Claim
28 words
A gas circulator as defined in claim 5, wherein the second radial backup bearing is an antifriction bearing and wherein the axial backup bearing is an antifriction bearing.
Claim 8
Dependent Claim
22 words
A gas circulator as defined in claim 5, wherein the first radial backup bearing includes a graphite bushing mounted on the stator.
Claim 9
Dependent Claim
24 words
A gas circulator as defined in claim 7, wherein the first radial backup bearing further includes a metal sleeve mounted on the rotor shaft.
Claim 10
Dependent Claim
47 words
A gas circulator as defined in claim 5, wherein the axial backup bearing and second radial backup bearing are spaced apart sufficiently to permit the backup bearings to provide substantially all radial support for the rotor when the first and second radial active magnetic bearings are deenergized.
Claim 11
Dependent Claim
54 words
A gas circulator as defined in claim 5, wherein the sealed chamber is defined by an inner member, an outer member, and sealing means for forming a seal between the inner and outer members, the outer member being substantially annular and at least part of the inner member being located within the outer member.
Claim 12
Dependent Claim
65 words
A gas circulator as defined in claim 10, wherein one of the rotor shaft and the inner member has a bore and the other of the rotor shaft and the inner member has an extension with a first end and a second end, the extension extending into the bore, a clearance existing between the extension and the bore when the active magnetic bearings are energized.
Claim 13
Dependent Claim
44 words
A gas circulator as defined in claim 11, wherein the rotor shaft has the bore and the inner member has the extension, the first end of the extension extending into the bore, the second end of the extension being connected to the inner member.
Claim 14
Dependent Claim
24 words
A gas circulator as defined in claim 12, wherein the second end of the extension is beveled and the rotor shaft is correspondingly beveled.
Claim 15
Dependent Claim
24 words
A gas circulator as defined in claim 12, wherein the first end of the extension is beveled and the rotor shaft is correspondingly beveled.
Claim 16
Dependent Claim
48 words
A gas circulator as defined in claim 11, wherein the inner member has the bore and the rotor shaft has the extension, the first end of the extension extending into the bore, the second end of the extension being connected to the second end of the rotor shaft.
Claim 17
Dependent Claim
24 words
A gas circulator as defined in claim 15, wherein the second end of the extension is beveled and the inner member is correspondingly beveled.
Claim 18
Dependent Claim
15 words
A gas circulator as defined in claim 10, further comprising means for braking the rotor.
Claim 19
Dependent Claim
49 words
A gas circulator as defined in claim 17, wherein the means for braking the rotor includes a first flange connected to the rotor shaft, a second flange connected to the inner member, and means for loading the first flange and the second flange at their respective beveled contacting surfaces.
Claim 20
Dependent Claim
34 words
A gas circulator as defined in claim 10, wherein the chamber contains a liquid lubricant, and wherein means for preventing the liquid lubricant from traveling toward the rotor shaft are located within the chamber.
Claim 21
Dependent Claim
28 words
A gas circulator as defined in claim 19, wherein the preventing means includes a ring which by centrifugal force urges the liquid lubricant away from the rotor shaft.
Claim 22
Dependent Claim
24 words
A gas circulator as defined in claim 5, further comprising control means for adjusting the position of the rotor while the rotor is rotating.
Claim 23
Dependent Claim
24 words
A gas circulator as defined in claim 21, wherein the control means includes means for sensing rotor vibrations and means for reducing rotor vibrations.
Claim 24
Independent Claim
86 words
A method for using a circulator for a gas-cooled nuclear reactor, comprising the steps of: supporting the circulator radially with a first active magnetic bearing and a second active magnetic bearing; supporting the circulator axially with a third active magnetic bearing; providing a first backup bearing for the first active magnetic bearing; providing a second backup bearing for the second active magnetic bearing; providing a third backup bearing for the third active magnetic bearing; and locating the second and third backup bearings in a sealed chamber.
Claim 25
Independent Claim
86 words
A method for using a circulator for a gas-cooled nuclear reactor, comprising the steps of: supporting the circulator radially with a first active magnetic bearing and a second active magnetic bearing; supporting the circulator axially with a third active magnetic bearing; providing a first backup bearing for the first active magnetic bearing; providing a second backup bearing for the second active magnetic bearing; providing a third backup bearing for the third active magnetic bearing; and locating the second and third backup bearings in a sealed chamber.
Claim 26
Dependent Claim
16 words
A method as defined in claim 23, further comprising the step of electrically driving the circulator.
Claim 27
Dependent Claim
26 words
A method as defined in claim 23, wherein the supporting steps and the providing steps are performed within a primary system pressure boundary for the nuclear
Claim 28
Dependent Claim
17 words
A method as defined in claim 23, further comprising the step of introducing a lubricant into the
Claim 29
Dependent Claim
19 words
A method as defined in claim 26, wherein the introducing step includes introducing a solid lubricant into the chamber.
Claim 30
Dependent Claim
19 words
A method as defined in claim 26, wherein the introducing step includes introducing a liquid lubricant into the chamber.
Claim 31
Dependent Claim
19 words
A method as defined in claim 23, further comprising the step of supplying a braking mechanism for the circulator.
Claim 32
Dependent Claim
24 words
A method as defined in claim 23, further comprising the step of installing the circulator with a rotor shaft in a substantially horizontal orientation.
Claim 33
Dependent Claim
24 words
A method as defined in claim 23, further comprising the step of installing the circulator with a rotor shaft in a substantially vertical orientation.
Claim 34
Dependent Claim
33 words
A method as defined in claim 31, wherein the locating step includes locating both of the second and third backup bearings in a sealed chamber positioned proximate the bottom of the rotor shaft.
Claim 35
Dependent Claim
17 words
A method as defined in claim 32, wherein each providing step includes providing an antifriction backup bearing.
Claim 36
Dependent Claim
159 words
A nuclear reactor system, comprising: a nuclear reactor contained within a primary system pressure boundary; a gas coolant for the nuclear reactor; and a gas circulator including a stator, a rotor having a rotor shaft with a first end and a second end, an impeller attached to the rotor shaft at the first end of the rotor shaft, a first radial active magnetic bearing positioned proximate the first end of the rotor shaft, a first radial backup bearing positioned proximate the first end of the rotor shaft, a second radial active magnetic bearing positioned proximate the second end of the rotor shaft, a second radial backup bearing positioned proximate the second end of the rotor shaft, an axial active magnetic bearing positioned between the first and second ends of the rotor shaft, an axial backup bearing positioned between the first and second ends of the rotor shaft; wherein the gas circulator is contained within the primary system pressure boundary.
Claim 37
Dependent Claim
159 words
A nuclear reactor system, comprising: a nuclear reactor contained within a primary system pressure boundary; a gas coolant for the nuclear reactor; and a gas circulator including a stator, a rotor having a rotor shaft with a first end and a second end, an impeller attached to the rotor shaft at the first end of the rotor shaft, a first radial active magnetic bearing positioned proximate the first end of the rotor shaft, a first radial backup bearing positioned proximate the first end of the rotor shaft, a second radial active magnetic bearing positioned proximate the second end of the rotor shaft, a second radial backup bearing positioned proximate the second end of the rotor shaft, an axial active magnetic bearing positioned between the first and second ends of the rotor shaft, an axial backup bearing positioned between the first and second ends of the rotor shaft; wherein the gas circulator is contained within the primary system pressure boundary.
Claim 38
Dependent Claim
18 words
A nuclear reactor system as defined in claim 34, wherein the rotor shaft has a substantially vertical orientation.
Claim 39
Dependent Claim
26 words
A nuclear reactor system as defined in claim 35, wherein the second radial backup bearing and the axial backup bearing are located within a sealed chamber.
Claim 40
Dependent Claim
43 words
A nuclear reactor system as defined in claim 36, wherein the first radial backup bearing includes a graphite bushing mounted on the stator, wherein the second radial backup bearing is an antifriction bearing, and wherein the axial backup bearing is an antifriction bearing.
Claim 41
Dependent Claim
25 words
A nuclear reactor system as defined in claim 37, wherein the first radial backup bearing further includes a metal sleeve mounted on the rotor shaft.
Claim 42
Dependent Claim
26 words
A nuclear reactor system as defined in claim 34, further comprising control means for controlling the active magnetic bearings to adjust the position of the rotor.
Claim 43
Dependent Claim
19 words
A nuclear reactor system as defined in claim 39, wherein the control means includes means for suppressing rotor vibrations.
Claim 44
Dependent Claim
27 words
A nuclear reactor system as defined in claim 34, wherein the active magnetic bearings include windings and wherein the windings are sealed off from the gas coolant.
Claim 45
Independent Claim
73 words
A method for operating a nuclear reactor, comprising the steps of: pumping a coolant through the nuclear reactor with a pump; supporting the pump radially with two active magnetic bearings; supporting the pump axially with an active magnetic bearing; providing backup bearings for the radial active magnetic bearings; providing a backup bearing for the axial active magnetic bearing; and enclosing one radial backup bearing and the axial backup bearing in a sealed chamber.
Claim 46
Independent Claim
73 words
A method for operating a nuclear reactor, comprising the steps of: pumping a coolant through the nuclear reactor with a pump; supporting the pump radially with two active magnetic bearings; supporting the pump axially with an active magnetic bearing; providing backup bearings for the radial active magnetic bearings; providing a backup bearing for the axial active magnetic bearing; and enclosing one radial backup bearing and the axial backup bearing in a sealed chamber.
Claim 47
Dependent Claim
20 words
A method as defined in claim 42, wherein the pumping step includes pumping a gas coolant through the nuclear reactor.
Claim 48
Dependent Claim
20 words
A method as defined in claim 42, wherein the pumping step includes pumping the coolant with an electrically driven pump.
Claim 49
Dependent Claim
23 words
A method as defined in claim 42, wherein the pumping step includes pumping the coolant with a pump having a substantially vertical shaft.
Claim 50
Dependent Claim
23 words
A method as defined in claim 42, wherein the pumping step includes pumping the coolant with a pump having a substantially horizontal shaft.
Claim 51
Dependent Claim
18 words
A method as defined in claim 42, further comprising the step of introducing a lubricant into the chamber.
Claim 52
Dependent Claim
19 words
A method as defined in claim 47, wherein the introducing step includes introducing a solid lubricant into the chamber.
Claim 53
Dependent Claim
19 words
A method as defined in claim 47, wherein the introducing step includes introducing a liquid lubricant into the chamber.
Claim 54
Dependent Claim
25 words
A method as defined in claim 42, wherein the providing and enclosing steps are performed within a primary system pressure boundary for the nuclear reactor.
Claim 55
Dependent Claim
32 words
A method as defined in claim 42, wherein each active magnetic bearing includes a stator, further comprising the step of sealing off the stators of the active magnetic bearings from the coolant.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-07-27 | 1991-01-26 | 1991-07-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-27 | 1995-01-26 | 1995-07-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-27 | 1999-01-26 | 1999-07-28 | $7700.00 | Window Closed / Lapsed |