Patent US5563490A successfully refreshed from Google Patents.
US5563490A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pump system with liquid cooling operation
Assignee: Ebara Corp
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Filing: 1994-09-20
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Granted: 1996-10-08
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Expires: 2014-09-20
Abstract
Abstract A pump control system has a pump unit composed of a turbo pump, a motor for operating the turbo pump, and a frequency/voltage converter for generating a frequency and a voltage to energize the motor. The rotational speed of the turbo pump is varied in order to equalize the current of the motor to a constant current irrespective of the head of the pump. The pump can be operated to take fully advantage of the current capacity of the motor.
Inventors
- 👤 Kyoji Kawaguchi
- 👤 Masakazu Yamamoto
- 👤 Yoshio Miyake
- 👤 Koji Isemoto
- 👤 Keita Uwai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:04
CPC Classifications
F; F04; F04D; F04D15/00; F04D15/0066
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
144 words
A pump system comprising: a pump unit composed of a turbo pump, a three-phase induction motor for operating said turbo pump, and a frequency/voltage converter for generating a frequency and a voltage to energize said three-phase induction motor, wherein an impeller of said turbo pump and a rotor of said motor are fixedly mounted on a main shaft which is supported by bearings, said motor also comprising a stator; means for keeping a ratio of said voltage to said frequency constant and varying a rotational speed of said turbo pump in order to equalize a current of said three-phase induction motor to a constant current irrespective of a head of the pump; and means for supplying a liquid pressurized by said impeller to at least one of spaces for thermal isolation between said stator and said bearings and between said stator and said rotor.
Claim 2
Dependent Claim
144 words
A pump system comprising: a pump unit composed of a turbo pump, a three-phase induction motor for operating said turbo pump, and a frequency/voltage converter for generating a frequency and a voltage to energize said three-phase induction motor, wherein an impeller of said turbo pump and a rotor of said motor are fixedly mounted on a main shaft which is supported by bearings, said motor also comprising a stator; means for keeping a ratio of said voltage to said frequency constant and varying a rotational speed of said turbo pump in order to equalize a current of said three-phase induction motor to a constant current irrespective of a head of the pump; and means for supplying a liquid pressurized by said impeller to at least one of spaces for thermal isolation between said stator and said bearings and between said stator and said rotor.
Claim 3
Dependent Claim
77 words
A pump system according to claim 1, wherein said means comprises a current detecting means for detecting said current of said motor, a current setting unit for setting said constant current, a comparator for comparing the detected current and the set constant current, and a frequency signal generator responsive to an output signal from said comparator for generating a frequency signal to vary said frequency in order to keep constant the current of said three-phase induction motor.
Claim 4
Dependent Claim
32 words
A pump system according to claim 2, further comprising means for setting an upper limit for said frequency signal to keep a rotational speed of said turbo pump below a predetermined speed.
Claim 5
Dependent Claim
45 words
A pump system according to claim 1, further comprising means for detecting a temperature of a stator winding of said three-phase induction motor, and control means for varying the constant current in order to keep the temperature of the stator winding below a predetermined value.
Claim 6
Dependent Claim
138 words
A pump system comprising: a pump unit composed of a turbo pump, a motor for operating said turbo pump, and a frequency/voltage converter for generating a frequency and a voltage to energize said motor, wherein an impeller of said turbo pump and a rotor of said motor are fixedly mounted on a main shaft which is supported by bearings said motor also comprising a stator; means for keeping a predetermined relationship of said voltage to said frequency and varying a rotational speed of said turbo pump in order to equalize a current of said motor to a constant current irrespective of a head of the pump; and means for supplying a liquid pressurized by said impeller to at least one of spaces for thermal isolation between said stator and said bearings and between said stator and said rotor.
Claim 7
Dependent Claim
138 words
A pump system comprising: a pump unit composed of a turbo pump, a motor for operating said turbo pump, and a frequency/voltage converter for generating a frequency and a voltage to energize said motor, wherein an impeller of said turbo pump and a rotor of said motor are fixedly mounted on a main shaft which is supported by bearings said motor also comprising a stator; means for keeping a predetermined relationship of said voltage to said frequency and varying a rotational speed of said turbo pump in order to equalize a current of said motor to a constant current irrespective of a head of the pump; and means for supplying a liquid pressurized by said impeller to at least one of spaces for thermal isolation between said stator and said bearings and between said stator and said rotor.
Claim 8
Dependent Claim
76 words
A pump control system according to claim 5, wherein said means comprises a current detecting means for detecting said current of said motor, a current setting unit for setting said constant current, a comparator for comparing the detected current and the set constant current, and a frequency signal generator responsive to an output signal from said comparator for generating a frequency signal to vary said frequency in order to keep constant the current of said motor.
Claim 9
Dependent Claim
33 words
A pump control system according to claim 6, further comprising means for setting an upper limit for said frequency signal to keep the rotational speed of said turbo pump below a predetermined speed.
Claim 10
Dependent Claim
43 words
A pump system according to claim 5, further comprising means for detecting a temperature of a stator winding of said motor, and control means for varying said constant current in order to keep said temperature of the stator winding below a predetermined value.
Claim 11
Dependent Claim
114 words
A pump system comprising: a pump unit composed of a turbo pump, a motor for operating said turbo pump, and a frequency/voltage converter for generating a frequency and a voltage to energize said motor, wherein an impeller of said turbo pump and a rotor of said motor are fixedly mounted on a main shaft which is supported by bearings, said motor also comprising a stator; means for equalizing a current of said three-phase induction motor to a constant current irrespective of a head of the pump; and means for supplying a liquid pressurized by said impeller to a space for thermal isolation between said stator and a heat producing portion other than said stator.
Claim 12
Dependent Claim
114 words
A pump system comprising: a pump unit composed of a turbo pump, a motor for operating said turbo pump, and a frequency/voltage converter for generating a frequency and a voltage to energize said motor, wherein an impeller of said turbo pump and a rotor of said motor are fixedly mounted on a main shaft which is supported by bearings, said motor also comprising a stator; means for equalizing a current of said three-phase induction motor to a constant current irrespective of a head of the pump; and means for supplying a liquid pressurized by said impeller to a space for thermal isolation between said stator and a heat producing portion other than said stator.
Claim 13
Dependent Claim
16 words
A pump system according to claim 9, wherein said pump unit comprises a full-circumferential flow pump.
Claim 14
Dependent Claim
16 words
A pump system according to claim 9, wherein said pump unit comprises a canned motor pump.
Claim 15
Dependent Claim
26 words
A pump system according to claim 9, wherein said heat producing portion other than said stator is at least one of bearings and a motor rotor.
Claim 16
Dependent Claim
110 words
A pump system comprising: a pump unit composed of a turbo pump, a motor for operating said turbo pump, and a frequency/voltage converter for generating a frequency and a voltage to energize said motor, wherein an impeller of said turbo pump and a rotor of said motor are fixedly mounted on a main shaft which is supported by bearings, said motor also comprising a stator; means for equalizing a current of said three-phase induction motor to a constant current irrespective of a head of the pump; and means for supplying a liquid to a space for thermal isolation between said stator and a heat producing portion other than said stator.
Claim 17
Dependent Claim
110 words
A pump system comprising: a pump unit composed of a turbo pump, a motor for operating said turbo pump, and a frequency/voltage converter for generating a frequency and a voltage to energize said motor, wherein an impeller of said turbo pump and a rotor of said motor are fixedly mounted on a main shaft which is supported by bearings, said motor also comprising a stator; means for equalizing a current of said three-phase induction motor to a constant current irrespective of a head of the pump; and means for supplying a liquid to a space for thermal isolation between said stator and a heat producing portion other than said stator.
Claim 18
Dependent Claim
16 words
A pump system according to claim 13, wherein said pump unit comprises a full-circumferential flow pump.
Claim 19
Dependent Claim
16 words
A pump system according to claim 13, wherein said pump unit comprises a canned motor pump.
Claim 20
Dependent Claim
26 words
A pump system according to claim 13, wherein said heat producing portion other than said stator is at least one of bearings and a motor rotor.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 7.5 Years (Year 8) | 2003-10-08 | 2004-04-08 | 2004-10-08 | $3760.00 | Window Closed / Lapsed |
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