US4151239A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Improvements in and relating to building blocks
Assignee: British Industrial Plastics Ltd
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Filing: 1977-10-11
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Granted: 1979-04-24
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Expires: 1997-10-11
Abstract
Abstract Here is disclosed a method of manufacturing building blocks filled with a cured aminoplast resin foam by forming a curable foam, presenting the cavity to and in sealing relationship with one end of a delivery pipe for the foam and injecting the curable foam through the delivery pipe into the cavity until a back pressure is developed in the delivery pipe. Apparatus for manufacturing the building blocks is also described.
Inventors
- 👤 Dennis H. Ogden
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:01
CPC Classifications
E; E04; E04C; E04C1/00; E04C1/40; E04C1/41; B; B28; B28B; B28B11/00; B28B11/04; B28B11/042; B28B11/043; B29; B29C; B29C44/00; B29C44/02; B29C44/12; B29C44/18; E04B; E04B2/00; E04B2/02; E04B2002/0256; E04B2002/0289; E04B2002/0293; Y; Y10; Y10S; Y10S264/00; Y10S264/02
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
110 words
A method of producing a building block having a cavity filled with a cured aminoplast resin foam, the method including the steps of forming a curable foam from an aqueous solution of a urea-formaldehyde resin solution and a curing agent for the resin, bringing the cavity to be filled into sealing engagement with a cover or shoe-like discharge outlet at the end of a delivery pipe for the foam, and injecting the foam into the cavity until a back pressure is developed in the delivery pipe, said back pressure being sufficient only to force some of said foam into the material of said block, whereby the foam is retained therein.
Claim 2
Independent Claim
110 words
A method of producing a building block having a cavity filled with a cured aminoplast resin foam, the method including the steps of forming a curable foam from an aqueous solution of a urea-formaldehyde resin solution and a curing agent for the resin, bringing the cavity to be filled into sealing engagement with a cover or shoe-like discharge outlet at the end of a delivery pipe for the foam, and injecting the foam into the cavity until a back pressure is developed in the delivery pipe, said back pressure being sufficient only to force some of said foam into the material of said block, whereby the foam is retained therein.
Claim 3
Dependent Claim
37 words
A method according to claim 1 comprising filling in turn successive cavities in a row of building blocks by progressively displacing said cavities into sealing relation with said discharge outlet at the end of the delivery pipe.
Claim 4
Dependent Claim
34 words
A method according to claim 1 wherein successive cavities are filled in turn by progressively displacing said discharge outlet at the end of the delivery pipe across and into sealing relation with said cavities.
Claim 5
Dependent Claim
26 words
A method according to claim 3 wherein the displacement is carried out by indexing in a step-wise manner and foam formation is discontinued during said indexing.
Claim 6
Dependent Claim
14 words
A method according to claim 3 wherein the displacement and foam formation are continuous.
Claim 7
Dependent Claim
32 words
A method according to claim 1, wherein successive cavities are filled in turn by progressively displacing said cavities into sealing relation with said discharge outlet at the end of the delivery pipe.
Claim 8
Dependent Claim
26 words
A method according to claim 6 wherein the displacement is carried out by indexing in a step-wise manner and foam formation is discontinued during said indexing.
Claim 9
Dependent Claim
14 words
A method according to claim 6 wherein the displacement and foam formation are continuous.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-04-23 | 1982-10-23 | 1983-04-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-04-23 | 1986-10-23 | 1987-04-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-04-23 | 1990-10-23 | 1991-04-24 | $7700.00 | Window Closed / Lapsed |