US3930538A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wellpoint with adjustable valve
Assignee: Griffin Dewatering Corp
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Filing: 1974-11-05
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Granted: 1976-01-06
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Expires: 1994-11-05
Abstract
Abstract A wellpoint having an outer screen pipe, and an inner intake pipe connected to a vacuum source. A positionable valve is mounted between the screen pipe and the intake pipe to regulate the amount of screen pipe surface subject to vacuum by the intake pipe.
Inventors
- 👤 Walter W. Brennan
- 👤 Charles R. Myers
- 👤 Paul E. Perry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 17:40
CPC Classifications
E; E03; E03B; E03B3/00; E03B3/06; E03B3/08; E03B3/16; E03B3/18; E21; E21B; E21B43/00; E21B43/02; E21B43/08; E21B43/086; E21B7/00; E21B7/18; E21B7/20
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
69 words
A wellpoint comprising: pipe means for the intake of liquid from the well and connection to vacuum producing means; screen means spaced apart from and surrounding said pipe means for admitting and maintaining a liquid supply for said pipe means; and slidably adjustable valve means located between said pipe means and said screen means for adjusting the amount of surface area of said screen pipe subjected to said vacuum.
Claim 2
Dependent Claim
69 words
A wellpoint comprising: pipe means for the intake of liquid from the well and connection to vacuum producing means; screen means spaced apart from and surrounding said pipe means for admitting and maintaining a liquid supply for said pipe means; and slidably adjustable valve means located between said pipe means and said screen means for adjusting the amount of surface area of said screen pipe subjected to said vacuum.
Claim 3
Dependent Claim
49 words
The wellpoint of claim 1 wherein said valve means comprises: a valve member slidably mounted on said pipe means and shaped to conform to the space between said screen means and said pipe means; and means for maintaining said valve members in a selected position on said screen pipe.
Claim 4
Dependent Claim
102 words
The wellpoint of claim 1 wherein said screen means is a cylindrical, intermittently slotted pipe and said pipe means is cylindrical and concentric within said screen means and removable therefrom and wherein said valve means comprises: an annular valve member slidably mounted on said pipe means and shaped to conform to the space between said pipe and screen means, said valve member having first and second chamfered edges abutting said pipe means; a first O-ring mounted on said pipe means and against said first chamfered edge; and a second O-ring member mounted on said pipe means and against said second chamfered edge.
Claim 5
Dependent Claim
29 words
The wellpoint of claim 1 further including means for positioning said pipe means within said screen means and enabling manual removal of said pipe means from said screen means.
Claim 6
Dependent Claim
118 words
A wellpoint comprising: a cylindrical screen pipe having a closed end for insertion into a well, an open end and openings formed intermittently on its length; a cylindrical pipe member removably mounted on one end concentrically within said open end of said screen pipe and adapted to be connected with vacuum producing means on its other end; an annular valve member slidably mounted on said pipe member and shaped to conform to the space between said screen and pipe member and having first and second chamfered edges abutting said pipe member; a first O-ring mounted on said pipe member and against said first edge; and a second O-ring mounted on said pipe member and against said second edge.
Claim 7
Dependent Claim
118 words
A wellpoint comprising: a cylindrical screen pipe having a closed end for insertion into a well, an open end and openings formed intermittently on its length; a cylindrical pipe member removably mounted on one end concentrically within said open end of said screen pipe and adapted to be connected with vacuum producing means on its other end; an annular valve member slidably mounted on said pipe member and shaped to conform to the space between said screen and pipe member and having first and second chamfered edges abutting said pipe member; a first O-ring mounted on said pipe member and against said first edge; and a second O-ring mounted on said pipe member and against said second edge.
Claim 8
Dependent Claim
54 words
In a wellpoint having an outer screen pipe for admitting and maintaining a supply of liquid and an inner vacuum producing pipe, the improvement comprising: slidably adjustable valve means located between the outer screen pipe and the vacuum producing pipe for adjusting the amount of surface of said screen pipe subjected to said vacuum.
Claim 9
Dependent Claim
54 words
In a wellpoint having an outer screen pipe for admitting and maintaining a supply of liquid and an inner vacuum producing pipe, the improvement comprising: slidably adjustable valve means located between the outer screen pipe and the vacuum producing pipe for adjusting the amount of surface of said screen pipe subjected to said vacuum.
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) | 1979-01-05 | 1979-07-07 | 1980-01-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-01-05 | 1983-07-07 | 1984-01-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-01-05 | 1987-07-07 | 1988-01-06 | $7700.00 | Window Closed / Lapsed |