US4923081A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Storage tanks with fabricated support ribs
Assignee: PATRIARCH PARTNERS AGENCY SERVICE LLC
•
Filing: 1988-01-25
•
Granted: 1990-05-08
•
Expires: 2008-01-25
Abstract
Abstract Improved reinforced plastic tanks and novel mandrel processes for producing them are disclosed. One aspect of the invention is concerned with an external support rib and a method for producing it. According to the invention, the rib is fabricated on a hollow rib form secured to the exterior of a tank with resilient netting and thread. The structure comprises chopped fibers and a resin which does not require a source of external heat to cure. The tank with the rib form secured to it is rotated as the lay-up is applied. Netting and threads are supplied to the rib form and they wrap around the rib lay-up and hold it in place until it cures. Also disclosed is a method for producing a double wall tank incorporating the novel rib. According to this aspect of the invention, the ribs are cured until they are at least tacky. Then, thin flexible panels are wrapped around the outside of the ribs and held in place by a wrap. The panels have a width which is less than the distance between rib centers so that a portion of the top of each rib is exposed between adjacent panels. Two outer endcap forms are positioned at the ends of the tank and an outer tank wall is fabricated over the panels, the exposed rib tops and the outer endcap forms, to produce the external wall of a double wall tank.
Inventors
- 👤 A. Michael Weaver
- 👤 Joseph R. Wiegand
- 👤 Dewey C. Stickley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 21:03
CPC Classifications
C; C07; C07D; C07D401/00; C07D401/02; C07D401/04; B; B29; B29C; B29C53/00; B29C53/56; B29C53/58; B29C53/583; B29C53/585; A; A61; A61K; A61K31/00; A61K31/33; A61K31/395; A61K31/435; A61K31/44; B29D; B29D22/00; B29D22/003; B29D24/00; B29D24/002; B29D24/008; B65; B65D; B65D90/00; B65D90/02; B65D90/029; C07D215/00; C07D215/02; C07D215/16; C07D215/48; C07D215/54; C07D215/56; C07D405/00; C07D405/02; C07D405/04; C07D471/00; C07D471/02; C07D471/04
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
132 words
A plastic, fiber reinforced storage tank comprising a cylindrically shaped side-wall, a pair of opposed end caps integrally connected to said side-wall and, together therewith, constituting an inner tank, and annular reinforcing ribs integrally connected to and supported on the exterior of said side-wall, said ribs comprising hollow rib forms and an overlayed structure of chopped fibers and liquid, hardenable resin, said chopped fibers being wetted by and dispersed within said hardenable resin, and including netting and threads in contract with said structure, said threads serving to hold said resin-wetted chopped fiber structure on said rib form against the force of gravity and said netting exerting a compressive action on said threads and overlayed structure so as to promote wetting of the chopped fibers and retain said rib forms on said side-wall.
Claim 2
Dependent Claim
132 words
A plastic, fiber reinforced storage tank comprising a cylindrically shaped side-wall, a pair of opposed end caps integrally connected to said side-wall and, together therewith, constituting an inner tank, and annular reinforcing ribs integrally connected to and supported on the exterior of said side-wall, said ribs comprising hollow rib forms and an overlayed structure of chopped fibers and liquid, hardenable resin, said chopped fibers being wetted by and dispersed within said hardenable resin, and including netting and threads in contract with said structure, said threads serving to hold said resin-wetted chopped fiber structure on said rib form against the force of gravity and said netting exerting a compressive action on said threads and overlayed structure so as to promote wetting of the chopped fibers and retain said rib forms on said side-wall.
Claim 3
Dependent Claim
84 words
The tank claimed in claim 1 wherein said resin is hardened and further including an outer tank comprising a cylindrically shaped side-wall connected and bonded to the exterior of said ribs and further including flow means for providing communication between the hollow spaces in each rib and the spaces between the ribs and between the inner and outer cylindrical walls, said flow means comprising hollow tubular inserts passing through said hardened resin and having an open end thereof terminating within said hollow rib form.
Claim 4
Dependent Claim
13 words
The storage tank of claim 1 wherein said thread is a polyester thread.
Claim 5
Dependent Claim
12 words
The storage tank of claim 3 wherein said netting is a polyamide.
Claim 6
Dependent Claim
118 words
In a plastic fiber reinforced storage tank having a cylindrically shaped side-wall and opposed end caps integrally connected to said wall and at least three axially displaced, outwardly extending annular ribs, the improvement wherein said ribs comprise outwardly extending rib forms connected to said side-wall, and wherein said ribs further comprise a mixture of hardenable resin and resin-wetted chopped fibers covering said rib forms, said chopped fibers being dispersed within said resin, netting in contact with said mixture and retaining said rib forms against said side-wall, and threads in contact with said mixture, said threads serving, during manufacture, to hold said mixture on the rib form, said netting also promoting the wetting of said chopped fibers and resin.
Claim 7
Dependent Claim
118 words
In a plastic fiber reinforced storage tank having a cylindrically shaped side-wall and opposed end caps integrally connected to said wall and at least three axially displaced, outwardly extending annular ribs, the improvement wherein said ribs comprise outwardly extending rib forms connected to said side-wall, and wherein said ribs further comprise a mixture of hardenable resin and resin-wetted chopped fibers covering said rib forms, said chopped fibers being dispersed within said resin, netting in contact with said mixture and retaining said rib forms against said side-wall, and threads in contact with said mixture, said threads serving, during manufacture, to hold said mixture on the rib form, said netting also promoting the wetting of said chopped fibers and resin.
Claim 8
Dependent Claim
12 words
The tank of claim 5 wherein said thread is a polyester thread.
Claim 9
Dependent Claim
10 words
The tank of claim 6 wherein said netting is polyamide.
Claim 10
Dependent Claim
154 words
In a plastic fiber reinforced storage tank having a cylindrically shaped side-wall and opposed end caps integrally connected to said wall and at least three axially displaced, outwardly extending annular ribs, the improvement wherein said ribs comprise outwardly extending rib forms connected to said side-wall, and wherein said ribs further comprise a mixture of resin and chopped fibers covering said rib forms, netting in contact with said mixture and retaining said rib forms against said side-wall, and threads in contact with said mixture, said threads serving, during manufacture, to promote the wetting of said chopped fibers and resin, and to hold said mixture on the rib form and wherein said tank further includes self-supporting panels respectively axially disposed between different adjacent two of said three ribs and having axial lengths less than the distance between the centerlines of said ribs to thereby provide a gap disposed between said panels, radially outwardly of said ribs.
Claim 11
Dependent Claim
154 words
In a plastic fiber reinforced storage tank having a cylindrically shaped side-wall and opposed end caps integrally connected to said wall and at least three axially displaced, outwardly extending annular ribs, the improvement wherein said ribs comprise outwardly extending rib forms connected to said side-wall, and wherein said ribs further comprise a mixture of resin and chopped fibers covering said rib forms, netting in contact with said mixture and retaining said rib forms against said side-wall, and threads in contact with said mixture, said threads serving, during manufacture, to promote the wetting of said chopped fibers and resin, and to hold said mixture on the rib form and wherein said tank further includes self-supporting panels respectively axially disposed between different adjacent two of said three ribs and having axial lengths less than the distance between the centerlines of said ribs to thereby provide a gap disposed between said panels, radially outwardly of said ribs.
Claim 12
Dependent Claim
53 words
The tank of claim 8 wherein said mixture is cured and further including a second cylindrically shaped sidewall disposed outwardly of said other sidewall, said second sidewall including an integral, radially inwardly extending portion disposed in said gap and in direct bonding contact with said resin and chopped glass mixture of said ribs.
Claim 13
Dependent Claim
17 words
The tank of claim 4 wherein said sidewall includes another portion directly fabricated on said self-supporting panels.
References Cited (Backward Citations)
US3661294A
Cited
US4071161A
Cited
US4375860A
Cited
US4562934A
Cited
US4660738A
Cited
US4676093A
Cited
US4778075A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-05-07 | 1993-11-06 | 1994-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-05-07 | 1997-11-06 | 1998-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-05-07 | 2001-11-06 | 2002-05-08 | $7700.00 | Window Closed / Lapsed |