US3738627A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Controller and control system
Assignee: Binks Sames Corp
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Filing: 1971-03-22
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Granted: 1973-06-12
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Expires: 1991-03-22
Abstract
Abstract A vacuum responsive controller and control system is disclosed for safely controlling the water level in paint spray booths of the type employing a high velocity air-current to entrain water from a reservoir and thereby aid in removing air-borne paint particles. The controller and system sample and signal the vacuum in the booth as an index of the dynamic conditions of water level and air velocity, and for vacuums below a threshold value, automatically raise the reservoir water level to achieve proper entrainment. The controller automatically responds to a lower vacuum to not supply water. Thus a failure of the air impeller will not result in water flowing to the reservoir. The controller includes a diaphragm moving in response to the pressure difference between vacuum and atmospheric inlets and valve means responsive to the diaphragm''s flexing over a range to not feed, feed, and again not feed an air pressure signal to a command signal output which controls a water supply valve. Adjustable mechanical biasing on the diaphragm allows for changing the operation point of the controller.
Inventors
- 👤 R Scotchmur
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 06:35
CPC Classifications
B; B01; B01D; B01D45/00; B01D45/04; B01D45/08; G; G05; G05D; G05D9/00; G05D9/04
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
244 words
In a control system for an air washing booth of the type in which impelled air entrains liquid from a reservoir into a washing chamber and in which the liquid surface level in the reservoir must be controlled within narrow limits for proper entrainment, the improvement comprising: means for sampling the vacuum in the washing chamber and deriving a signal related thereto; means for suppLying liquid to the reservoir; an interface valve for controlling said liquid supplying means and including operating means responsive to very low air pressure; a low pressure air supply for said operating means; and a controller including valve means connected to said air supply and said operating means and having vent means therein for selectively connecting said air supply to said operating means and venting both said air supply and said operating means, said controller being coupled to said sampling means and responsive to the vacuum signal from said means to operate said valve means to connect said air supply to said operating means in response to a signal representative of a vacuum less than a first threshold value, but not for a signal representative of a vacuum less than a second value which is less than the first value, whereby liquid is supplied to the reservoir at vacuums intermediate said first and second values to maintain a given liquid surface level in the reservoir, but not at vacuums above or below said values to prevent overfilling of the reservoir.
Claim 2
Dependent Claim
244 words
In a control system for an air washing booth of the type in which impelled air entrains liquid from a reservoir into a washing chamber and in which the liquid surface level in the reservoir must be controlled within narrow limits for proper entrainment, the improvement comprising: means for sampling the vacuum in the washing chamber and deriving a signal related thereto; means for suppLying liquid to the reservoir; an interface valve for controlling said liquid supplying means and including operating means responsive to very low air pressure; a low pressure air supply for said operating means; and a controller including valve means connected to said air supply and said operating means and having vent means therein for selectively connecting said air supply to said operating means and venting both said air supply and said operating means, said controller being coupled to said sampling means and responsive to the vacuum signal from said means to operate said valve means to connect said air supply to said operating means in response to a signal representative of a vacuum less than a first threshold value, but not for a signal representative of a vacuum less than a second value which is less than the first value, whereby liquid is supplied to the reservoir at vacuums intermediate said first and second values to maintain a given liquid surface level in the reservoir, but not at vacuums above or below said values to prevent overfilling of the reservoir.
Claim 3
Dependent Claim
60 words
In a control system as set forth in claim 1, said interface valve comprising a normally closed liquid controlling valve and the operating means thereof comprising an air pressure responsive diaphragm of relatively large area for opening the valve at low air pressures, said diaphragm also isolating the liquid part of the system from the air part of the system.
Claim 4
Dependent Claim
56 words
In a control system as set forth in claim 2, said diaphragm being coupled to said liquid controlling valve by a small diameter valve stem, and sealing means for said stem, said sealing means and the small diameter of said stem further aiding in isolating the liquid part of the system from the air part thereof.
Claim 5
Dependent Claim
54 words
In a control system as set forth in claim 1, said controller valve means comprising a first valve opened at vacuums greater than said first value and seated at vacuums less than said first value, and a second valve normally seated on said first valve and opened at vacuums less than said second value.
References Cited (Backward Citations)
US3364660A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-11 | 1976-12-11 | 1977-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-11 | 1980-12-11 | 1981-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-11 | 1984-12-11 | 1985-06-12 | $7700.00 | Window Closed / Lapsed |