US3814374A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Retractable casting core box with elastomeric joint seal
Assignee: Ameron Inc
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Filing: 1972-07-10
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Granted: 1974-06-04
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Expires: 1992-07-10
Abstract
Abstract A retractable core for use with an outer form in producing concrete castings includes a rectangular wall-forming box having a hollow interior and an opening at its bottom to allow access to its interior. The walls of the box are separated symmetrically into four quadrants, and the lines of separation between quadrants are sealed by a compressible elastomer. A retracting mechanism inside the box is connected to each quadrant. In use, concrete is poured over the box, and after the concrete cures, the retracting mechanism pulls each quadrant toward the center of the core to compress the elastomeric seal and thereby shrink the size of the core. The casting is then lifted over the core. Each quadrant is mounted on a separate set of elastically bendable support arms which deflect during retraction of the core and the subsequent return of the core to its initial wall-forming position.
Inventors
- 👤 P Beemer
- 👤 G Huck
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:46
CPC Classifications
B; B28; B28B; B28B7/00; B28B7/0002; B28B7/0011; B28B7/22
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
235 words
A retractable casting core for use with an outer form in the casting of generally hollow concrete products, the casting core comprising wall-forming means in the form of a hollowed rectangular box having an outer mold surface which forms the contour of a hollowed interior of a concrete casting, the outer mold surface of the wall-forming means being separated into wall sections cooperating with each other to form the contour of the concrete casting interior, the wall-forming means having one open end for access to a hollowed interior portion of the retractable casting core, the box being spearated substantially symmetrically into four quadrants with a compressible elastomeric joint seal being disposed along eacH line of separation between the quadrants, and means in the hollowed interior portion of the casting core for applying a force to retract each of the wall sections inwardly away from the interior of the casting, the wall retracting means directing a component of its retracting force in a direction transverse to the joint seal which borders each wall section to compress the seal to allow the wall sections to move toward each other as they move inwardly from the interior of the casting, the retracting means also directing a component of its retracting force in a direction eccentric of the centroid of the seal such that the seal is substantially prevented from bulging beyond the outer surface of the wall sections.
Claim 2
Dependent Claim
235 words
A retractable casting core for use with an outer form in the casting of generally hollow concrete products, the casting core comprising wall-forming means in the form of a hollowed rectangular box having an outer mold surface which forms the contour of a hollowed interior of a concrete casting, the outer mold surface of the wall-forming means being separated into wall sections cooperating with each other to form the contour of the concrete casting interior, the wall-forming means having one open end for access to a hollowed interior portion of the retractable casting core, the box being spearated substantially symmetrically into four quadrants with a compressible elastomeric joint seal being disposed along eacH line of separation between the quadrants, and means in the hollowed interior portion of the casting core for applying a force to retract each of the wall sections inwardly away from the interior of the casting, the wall retracting means directing a component of its retracting force in a direction transverse to the joint seal which borders each wall section to compress the seal to allow the wall sections to move toward each other as they move inwardly from the interior of the casting, the retracting means also directing a component of its retracting force in a direction eccentric of the centroid of the seal such that the seal is substantially prevented from bulging beyond the outer surface of the wall sections.
Claim 3
Dependent Claim
16 words
Apparatus according to claim 1 in which the elastomeric seal is made of a non-porous elastomer.
Claim 4
Dependent Claim
14 words
Apparatus according to claim 1 in which the elastomeric seal is substantially volumetrically incompressible.
Claim 5
Dependent Claim
29 words
Apparatus according to claim 1 in which the wall retracting means comprises at least one elongated retraction arm connection to each quadrant, and means for retracting each retraction arm.
Claim 6
Dependent Claim
42 words
Apparatus according to claim 1 in which each quadrant includes an upstanding end wall, an upstanding side wall which meets the end wall to form an upright corner of the box, and a top panel above the side wall and end wall.
Claim 7
Dependent Claim
31 words
Apparatus according to claim 5 in which each wall retracting means comprises a separate elongated retraction arm connected to the upright corner of each quadrant, and means for retracting each arm.
Claim 8
Dependent Claim
161 words
Apparatus according to claim 5 in which the retraction arms comprise a spider arrangement crossing at the central axis of the interior of the box, each arm being mounted to swivel about a horizontal axis, and in which the retraction arms are located in the upper interior portion of the box, and a second set of retraction arms, each of which arms is connected to an upright corner of a respective quadrant, the arms in the second set being in a spider arrangement so that they cross at the central axis of the interior of the box, and are disposed in the lower interior portion of the box, and including an extendable and contractable, vertically extending arm disposed on the central axis of the interior of the box and connected between the first and second sets of spiders, whereby extension and contraction of the vertical arm pulls the upper and lower spiders inwardly to retract the quadrants of the inner core.
Claim 9
Dependent Claim
20 words
Apparatus according to claim 1 in which each wall section is mounted on a separate set of elongated movable supports.
Claim 10
Dependent Claim
236 words
A retractable casting core for use with an outer form in the casting of generally hollow concrete products, the casting core comprising wall-forming means having an outer surface for forming the contour of a hollowed three-dimensional interior of a concrete casting, the wall-forming means having a side portion which forms a closed mold surface and is defined by intersecting first and second planes, and a top portion forming a mold surface which is integral with the side portion and is defined by a third plane which intersects the first and second planes so the combined side portion and top portion of the wall-forming means provide a continuous three-dimensional mold surface, the top and side portions being separated into wall sections cooperating with each other to form the contour of the concrete casting interior, the wall sections cooperating to form a hollowed interior area of the retractable casting core, a compressible elastomeric joint seal between the wall sections, and means in the hollowed interior area of the casting core for applying a force to retract each of the wall sections inwardly away from the interior of the concrete casting, the wall retracting means directing a component of its retracting force in a direction transverse to the joint seal which borders each wall section to compress the seal to allow the wall sections to move toward each other as they move inwardly from the intErior of the casting.
Claim 11
Dependent Claim
236 words
A retractable casting core for use with an outer form in the casting of generally hollow concrete products, the casting core comprising wall-forming means having an outer surface for forming the contour of a hollowed three-dimensional interior of a concrete casting, the wall-forming means having a side portion which forms a closed mold surface and is defined by intersecting first and second planes, and a top portion forming a mold surface which is integral with the side portion and is defined by a third plane which intersects the first and second planes so the combined side portion and top portion of the wall-forming means provide a continuous three-dimensional mold surface, the top and side portions being separated into wall sections cooperating with each other to form the contour of the concrete casting interior, the wall sections cooperating to form a hollowed interior area of the retractable casting core, a compressible elastomeric joint seal between the wall sections, and means in the hollowed interior area of the casting core for applying a force to retract each of the wall sections inwardly away from the interior of the concrete casting, the wall retracting means directing a component of its retracting force in a direction transverse to the joint seal which borders each wall section to compress the seal to allow the wall sections to move toward each other as they move inwardly from the intErior of the casting.
Claim 12
Dependent Claim
55 words
Apparatus according to claim 9 in which the wall-forming means is shaped as a hollowed rectangular box, with one open end for access to a hollow interior of the box, and in which the box is separated substantially symmetrically into four quadrants, the joint seal being aligned with each line of separation between the quadrants.
Claim 13
Dependent Claim
29 words
Apparatus according to claim 10 in which the wall retracting means comprises at least one elongated retraction arm connected to each quadrant, and means for retracting each retraction arm.
Claim 14
Dependent Claim
50 words
Apparatus according to claim 10 in which the wall-forming means is engaged with the joint seal to direct a component of its retracting force in a direction eccentric to the centroid of the seal such that the seal is substantially prevented from bulging beyond the outer surface of the quadrants.
Claim 15
Dependent Claim
216 words
A retractable casting core for use with an outer form in a concrete mold assembly, the retractable casting core comprising wall-forming means for providing an outer surface to form the contour of a hollowed three-dimensional interior of a concrete casting, the wall-forming means being divided into a plurality of separate wall sections having cooperating outer surfaces which form the three-dimensional contour of the concrete casting interior, the wall sections cooperating to form a hollowed interior portion of the casting core, the separate wall sections being spaced apart from one another to define a plurality of lines of separation spaced around the wall-forming means, a compressible elastomeric joint seal disposed in the lines of separation between the separate wall sections, and means in the hollowed interior portion of the casting core for applying a retracting force to the wall sections to move each wall section relative to the other wall sections inwardly toward the interior of the casting core and away from the casting, the wall retracting means directing a component of its retracting force in a direction transverse to the joint seal in each lines of separation between the wall sections to compress the joint seal to allow the wall sections to move toward each other as they move inwardly from the interior of the casting.
Claim 16
Dependent Claim
216 words
A retractable casting core for use with an outer form in a concrete mold assembly, the retractable casting core comprising wall-forming means for providing an outer surface to form the contour of a hollowed three-dimensional interior of a concrete casting, the wall-forming means being divided into a plurality of separate wall sections having cooperating outer surfaces which form the three-dimensional contour of the concrete casting interior, the wall sections cooperating to form a hollowed interior portion of the casting core, the separate wall sections being spaced apart from one another to define a plurality of lines of separation spaced around the wall-forming means, a compressible elastomeric joint seal disposed in the lines of separation between the separate wall sections, and means in the hollowed interior portion of the casting core for applying a retracting force to the wall sections to move each wall section relative to the other wall sections inwardly toward the interior of the casting core and away from the casting, the wall retracting means directing a component of its retracting force in a direction transverse to the joint seal in each lines of separation between the wall sections to compress the joint seal to allow the wall sections to move toward each other as they move inwardly from the interior of the casting.
Claim 17
Dependent Claim
42 words
Apparatus according to claim 13 in which the retracting means also directs the component of its retracting force eccentric to the centroid of the seal such that the seal is substantially prevented from bulging beyond the outer surface of the wall sections.
Claim 18
Dependent Claim
30 words
Apparatus according to claim 13 in which the wall sections are symmetrically arranged around the retractable casting core, and in which the retracting means retract the wall sections in unison.
Claim 19
Dependent Claim
29 words
Apparatus according to claim 15 in which at least one elongated retracting arm is connected to each wall section, and including means for retracting the retracting arms in unison.
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) | 1977-06-03 | 1977-12-03 | 1978-06-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-06-03 | 1981-12-03 | 1982-06-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-06-03 | 1985-12-03 | 1986-06-04 | $7700.00 | Window Closed / Lapsed |