Patent US3845480A successfully refreshed from Google Patents.
US3845480A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Particulate detector system
Assignee: Air Technologies Inc
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Filing: 1973-02-20
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Granted: 1974-10-29
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Expires: 1993-02-20
Abstract
Abstract The dust particle content in the environment of a magnetic disc storage device is continuously monitored. The particles are passed through a scattering chamber and monitored by a photo cell. When the particle content approaches an undesirable level, the photo cell develops a signal which is fed to and operates a detection circuit which controls an alarm to indicate undesirable content level.
Inventors
- 👤 S Steinberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 20:01
CPC Classifications
G; G01; G01N; G01N21/00; G01N21/17; G01N21/47; G01N21/49; G01N21/53
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
249 words
A system for detecting particulate level content within a selected environment, comprising, means for providing a confined passageway for movement of particulate matter there-through, means for moving a sampling of particulate matter from the selected environment and through the passageway of the providing means, means Responsive to the content level of the particulate matter being moved through the confined passageway for developing a signal at least when the content level is at a predetermined level, means for indicating the development of the signal by the developing means to indicate that the content level of the particulate matter has reached at least the predetermined level, and means responsive to the development of the signal by the developing means for operating the indicating means, the operating means including a detection circuit which operates in response to the signal developed by the developing means to generate a signal, the detection circuit including a vacuum tube triode circuit having adjustable cathode self-bias and a gridbias circuit for controlling operation of the tube in response to the signal developed by the developing means, and means for applying a predetermined potential to the grid-bias circuit in place of a potential normally applied thereto when the developed signal is applied to the grid-bias circuit so that the self-bias can be adjusted to calibrate the tube to operate precisely when the developed signal is subsequently applied to the gird-bias circuit, said predetermined potential being representative of the predetermined level of particulate material which is to be detected.
Claim 2
Independent Claim
249 words
A system for detecting particulate level content within a selected environment, comprising, means for providing a confined passageway for movement of particulate matter there-through, means for moving a sampling of particulate matter from the selected environment and through the passageway of the providing means, means Responsive to the content level of the particulate matter being moved through the confined passageway for developing a signal at least when the content level is at a predetermined level, means for indicating the development of the signal by the developing means to indicate that the content level of the particulate matter has reached at least the predetermined level, and means responsive to the development of the signal by the developing means for operating the indicating means, the operating means including a detection circuit which operates in response to the signal developed by the developing means to generate a signal, the detection circuit including a vacuum tube triode circuit having adjustable cathode self-bias and a gridbias circuit for controlling operation of the tube in response to the signal developed by the developing means, and means for applying a predetermined potential to the grid-bias circuit in place of a potential normally applied thereto when the developed signal is applied to the grid-bias circuit so that the self-bias can be adjusted to calibrate the tube to operate precisely when the developed signal is subsequently applied to the gird-bias circuit, said predetermined potential being representative of the predetermined level of particulate material which is to be detected.
Claim 3
Dependent Claim
34 words
The system as recited in claim 1 wherein the operating means further include relay means operable in response to the generated signal of the detection circuit for controlling the indicating means for operation thereof.
Claim 4
Dependent Claim
47 words
The system as recited in claim 1, and means for delaying the operation of the indicating means for a predetermined period after the developing means has developed the signal to determine whether the content level is sustained at least at the predetermined level for the predetermined period.
Claim 5
Dependent Claim
37 words
The system as recited in claim 1, wherein the providing means includes a scattering chamber having a particulate entry section and a particulate exit section, the entry section communicating with the exit section by the confined passageway.
Claim 6
Dependent Claim
31 words
The system as recited in claim 1, wherein the moving means includes a suction pump for drawing the sample of particulate matter from the selected environment and through the providing means.
Claim 7
Dependent Claim
82 words
The system as recited in claim 1, wherein the developing means includes a light positioned adjacent to a portion of the providing means and directing light rays onto the particulate matter being moved through the providing means, and a photo cell positioned adjacent to another portion of the providing means in a position to be sensitive to light reflected from the particulate matter passing through the providing means for developing the signal when the content level reaches at least the predetermined level.
Claim 8
Dependent Claim
25 words
The system as recited in claim 1, and means for calibrating the detection circuit to respond and operate when the developing means develops the signal.
Claim 9
Dependent Claim
17 words
The system as recited in claim 1, wherein the indicating means includes a lamp, and a buzzer.
Claim 10
Dependent Claim
15 words
The system as recited in claim 1, and means for operating the indicating means intermittently.
Claim 11
Independent Claim
281 words
A system for detecting particulate level content within a selected environment, comprising, means for providing a single confined passageway for movement of particulate matter therethrough, means for moving a sampling of particulate matter from the selected environment and through the single passageway of the providing means, means responsive solely to the presence and content level of the particulate matter being moved through the single confined passageway for developing a signal at least when the content level is at a predetermined level, means for indicating the development of the signal by the developing means to indicate the presence of the particulate matter and that the content level thereof has reached at least the predetermined level, and means responsive to the development of the signal by the developing means for operating the indicating means, the operating meaNs including a detection circuit which operates in respone to the signal developed by the developing means to generate a signal, and relay means operable in response to the generated signal of the detection circuit for controlling the indicating means for operation thereof, the detection circuit including a vacuum tube triode circuit having adjustable cathode self-bias and a grid-bias circuit for controlling operation of the tube in response to the signal developed by the developing means, and means for applying a predetermined potential to the grid-bias circuit in place of a potential normally applied thereto when the developed signal is applied to the grid-bias circuit so that the self-bias can be adjusted to calibrate the tube to operate precisely when the developed signal is subsequently applied to the grid-bias circuit, said predetermined potential being representative of the predetermined level of particulate material Which is to be detected.
Claim 12
Independent Claim
281 words
A system for detecting particulate level content within a selected environment, comprising, means for providing a single confined passageway for movement of particulate matter therethrough, means for moving a sampling of particulate matter from the selected environment and through the single passageway of the providing means, means responsive solely to the presence and content level of the particulate matter being moved through the single confined passageway for developing a signal at least when the content level is at a predetermined level, means for indicating the development of the signal by the developing means to indicate the presence of the particulate matter and that the content level thereof has reached at least the predetermined level, and means responsive to the development of the signal by the developing means for operating the indicating means, the operating meaNs including a detection circuit which operates in respone to the signal developed by the developing means to generate a signal, and relay means operable in response to the generated signal of the detection circuit for controlling the indicating means for operation thereof, the detection circuit including a vacuum tube triode circuit having adjustable cathode self-bias and a grid-bias circuit for controlling operation of the tube in response to the signal developed by the developing means, and means for applying a predetermined potential to the grid-bias circuit in place of a potential normally applied thereto when the developed signal is applied to the grid-bias circuit so that the self-bias can be adjusted to calibrate the tube to operate precisely when the developed signal is subsequently applied to the grid-bias circuit, said predetermined potential being representative of the predetermined level of particulate material Which is to be detected.
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) | 1977-10-28 | 1978-04-29 | 1978-10-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-28 | 1982-04-29 | 1982-10-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-28 | 1986-04-29 | 1986-10-29 | $7700.00 | Window Closed / Lapsed |