US4756669A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air compressor control apparatus
Assignee: Nabco Ltd
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Filing: 1987-07-23
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Granted: 1988-07-12
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Expires: 2007-07-23
Abstract
Abstract An air compressor pressure adjustment device designed such that any values between two set points are determined and used as first and second standard values. When the air pressure in the reservoir decreases to the first standard value the air compressor is driven at a low speed. When the air pressure increases in the reservoir and reaches an upper limit set point the compressor is turned off. When this air pressure decreases to less than the lower limit set point, the air compressor is started once more.
Inventors
- 👤 Yasuhisa Hata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 19:23
CPC Classifications
F; F04; F04B; F04B49/00; F04B49/02; F04B49/025
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
286 words
A pressure adjustment device for an air compressor of a railway car air supply system, said pressure adjustment device comprising: (a) a pressure sensor connected to an air reservoir in such air supply system to determine an air pressure in such air reservoir and to transmit a signal having a value that is representative of such air pressure; (b) a first comparator means connected to receive said signal from said pressure sensor for comparing said value with a first predetermined value; (c) a first means connected to said first comparator means for providing said first predetermined value; (d) a first signal output means connected to receive a signal from said first comparator means for passing a first control signal to an air compressor drive motor based on said signal received from said first comparator means; (e) a second comparator means connected to receive said signal from said pressure sensor for comparing said value with a second predetermined value; (f) a second means connected to said second comparator means for providing said second predetermined value; (g) a second signal output means connected to receive a signal from said second comparator means for passing a second control to such air compressor drive motor based on said signal received from said second comparator means; (h) a timer connected intermediate said second comparator means and said second signal output means; (i) a variable resistor connected at a first end thereof to said signal from said sensor and at a second end thereof to said signal from said first comparator means; and (j) a variable resistor connected at a first end thereof to said signal from said sensor and at a second end thereof to said from said second comparator means.
Claim 2
Dependent Claim
286 words
A pressure adjustment device for an air compressor of a railway car air supply system, said pressure adjustment device comprising: (a) a pressure sensor connected to an air reservoir in such air supply system to determine an air pressure in such air reservoir and to transmit a signal having a value that is representative of such air pressure; (b) a first comparator means connected to receive said signal from said pressure sensor for comparing said value with a first predetermined value; (c) a first means connected to said first comparator means for providing said first predetermined value; (d) a first signal output means connected to receive a signal from said first comparator means for passing a first control signal to an air compressor drive motor based on said signal received from said first comparator means; (e) a second comparator means connected to receive said signal from said pressure sensor for comparing said value with a second predetermined value; (f) a second means connected to said second comparator means for providing said second predetermined value; (g) a second signal output means connected to receive a signal from said second comparator means for passing a second control to such air compressor drive motor based on said signal received from said second comparator means; (h) a timer connected intermediate said second comparator means and said second signal output means; (i) a variable resistor connected at a first end thereof to said signal from said sensor and at a second end thereof to said signal from said first comparator means; and (j) a variable resistor connected at a first end thereof to said signal from said sensor and at a second end thereof to said from said second comparator means.
Claim 3
Dependent Claim
40 words
A pressure adjustment device, according to claim 1, wherein at least one of said first predetermined value and said second predetermined value is variable and at least one of said first means and said second means is a variable resistor.
Claim 4
Dependent Claim
34 words
A pressure adjustment device, according to claim 2, wherein each of said first predetermined value and said second predetermined value are adjustable and both said first means and said second means are variable resistors.
References Cited (Backward Citations)
US1346898A
Cited
US3985467A
Cited
US4149827A
Cited
DE2717224A1
Cited
US4201517A
Cited
JPS5510171A
Cited
DE3118221A1
Cited
US4476886A
Cited
EP0085285A1
Cited
US4518316A
Cited
JPS59108886A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-07-12 | 1992-01-11 | 1992-07-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-07-12 | 1996-01-11 | 1996-07-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-07-12 | 2000-01-11 | 2000-07-12 | $7700.00 | Window Closed / Lapsed |