Patent US4164034A successfully refreshed from Google Patents.
US4164034A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Compressor surge control with pressure rate of change control
Assignee: Sundstrand Corp
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Filing: 1977-09-14
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Granted: 1979-08-07
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Expires: 1997-09-14
Abstract
Abstract A surge control system for controlling and preventing a surge condition and a method of controlling surge in a fixed or variable speed compressor or a compressor having a variable geometry which provides air to a pneumatic load. A transducer provides a signal proportional to the outlet pressure of the air from the compressor. The signal is differentiated with respect to time and if a surge condition is ensuing, the absolute value of the differentiated signal is greater than a reference. When the differentiated signal is greater than the reference, a portion of the air supplied to the load is vented to reduce the outlet pressure. A reduction in the outlet pressure alleviates the ensuing surge condition and the absolute value of the differentiated signal decreases, causing the venting valve to close.
Inventors
- 👤 Timothy F. Glennon
- 👤 Theodore E. Sarphie
- 👤 Dennis T. Faulkner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:22
CPC Classifications
F; F04; F04D; F04D27/00; F04D27/02; F04D27/0207
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
90 words
A control system for preventing surge in a compressor which supplies air to a pneumatic load comprising: means for sensing the air pressure at the outlet of the compressor; means for generating a signal proportional to the absolute value of the rate of change of the air pressure; means for generating a first control signal if said signal proportional to the absolute value is greater than a first value; means for generating a second control signal if said signal proportional to the absolute value is less than a second value;
Claim 2
Dependent Claim
90 words
A control system for preventing surge in a compressor which supplies air to a pneumatic load comprising: means for sensing the air pressure at the outlet of the compressor; means for generating a signal proportional to the absolute value of the rate of change of the air pressure; means for generating a first control signal if said signal proportional to the absolute value is greater than a first value; means for generating a second control signal if said signal proportional to the absolute value is less than a second value;
Claim 3
Dependent Claim
13 words
means for summing said first control signal with said second control signal; and
Claim 4
Dependent Claim
13 words
means for summing said first control signal with said second control signal; and
Claim 5
Dependent Claim
39 words
means coupled to said summing means for generating a valve open signal when said first control signal is received from said summer, and for generating a valve closed signal when said second control signal is received from said summer.
Claim 6
Dependent Claim
39 words
means coupled to said summing means for generating a valve open signal when said first control signal is received from said summer, and for generating a valve closed signal when said second control signal is received from said summer.
Claim 7
Dependent Claim
35 words
The control system of claim 1 wherein said means for generating a valve open command signal and a valve closed command signal is a clamped integrator circuit for providing a voltage of a selected polarity.
Claim 8
Dependent Claim
28 words
The control system of claim 1 wherein the means for generating a first control signal has a higher gain than said means for generating a second control signal.
Claim 9
Dependent Claim
18 words
The control system of claim 1 wherein said first value is of greater magnitude than said second value.
Claim 10
Independent Claim
180 words
A system for controlling surge in a compressor which supplies air to a pneumatic load comprising: a sensor coupled to the output of the compressor for sensing the outlet pressure; a first circuit for providing a signal proportional to the absolute value of the first derivative of the outlet pressure; means for generating a first voltage if said signal is greater than a first value and for generating a second voltage if said signal is less than a second value; a second circuit having a first gain coupled to said generating means for multiplying said first voltage by the first gain; a third circuit having a second gain coupled to said generating means for multiplying said second voltage by the second gain; means coupled to said second and third circuits for summing the signals from said circuits to provide a vent valve command signal; an integrator responsive to said summer output for providing an output voltage; and a valve coupled between the output of the compressor and the load for venting air in an amount proportional to said output voltage.
Claim 11
Independent Claim
180 words
A system for controlling surge in a compressor which supplies air to a pneumatic load comprising: a sensor coupled to the output of the compressor for sensing the outlet pressure; a first circuit for providing a signal proportional to the absolute value of the first derivative of the outlet pressure; means for generating a first voltage if said signal is greater than a first value and for generating a second voltage if said signal is less than a second value; a second circuit having a first gain coupled to said generating means for multiplying said first voltage by the first gain; a third circuit having a second gain coupled to said generating means for multiplying said second voltage by the second gain; means coupled to said second and third circuits for summing the signals from said circuits to provide a vent valve command signal; an integrator responsive to said summer output for providing an output voltage; and a valve coupled between the output of the compressor and the load for venting air in an amount proportional to said output voltage.
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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) | 1982-08-06 | 1983-02-05 | 1983-08-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-08-06 | 1987-02-05 | 1987-08-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-08-06 | 1991-02-05 | 1991-08-07 | $7700.00 | Window Closed / Lapsed |