US3837613A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Device for stripping forms from cast concrete structures
Assignee: Individual
•
Filing: 1973-03-19
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Granted: 1974-09-24
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Expires: 1993-03-19
Abstract
Abstract A device having an apertured reaction plate for engagement against the concrete forming face of a concrete form, and a hollow bushing extending coaxially from the reaction plate for engagement through a hole in the form. A plug is provided for the aperture to prevent ingress of concrete and means such as a bolt or a hydraulic or pneumatic ram are provided for exerting a force through the hollow bushing and plug against the concrete to effect separation of the form from the concrete.
Inventors
- 👤 J Sontag
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:10
CPC Classifications
B; B28; B28B; B28B7/00; B28B7/10; B28B7/12; E; E04; E04G; E04G19/00
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
203 words
A device for use with a concrete form in stripping the form from a cast and set concrete structure, said device comprising an apertured reaction plate for engagement against the concrete forming face of the form, said plate having a large under surface to bear against a large area of said form face and a large outer surface to bear against the concrete, a hollow bushing extending coaxially from the aperture in the reaction plate to extend through a cooperatively formed hole in the form, an actuating unit engageable with the hollow bushing and having a ram head drivable through said bushing, a plug removably fitting in the plate aperture at the outer surface of the plate and completely closing the aperture, said plug having a hollow cylindrical portion extending into the bushing away from the outer surface of the plate and into which said actuating unit movably fits, and engagement means within the bushing for connecting the actuating means to the bushing, whereby a form incorporating said device can be separated from a concrete structure cast thereagainst by engaging an actuating unit with said hollow bushing and driving the ram head thereof through the bushing to exert pressure on the concrete structure.
Claim 2
Independent Claim
203 words
A device for use with a concrete form in stripping the form from a cast and set concrete structure, said device comprising an apertured reaction plate for engagement against the concrete forming face of the form, said plate having a large under surface to bear against a large area of said form face and a large outer surface to bear against the concrete, a hollow bushing extending coaxially from the aperture in the reaction plate to extend through a cooperatively formed hole in the form, an actuating unit engageable with the hollow bushing and having a ram head drivable through said bushing, a plug removably fitting in the plate aperture at the outer surface of the plate and completely closing the aperture, said plug having a hollow cylindrical portion extending into the bushing away from the outer surface of the plate and into which said actuating unit movably fits, and engagement means within the bushing for connecting the actuating means to the bushing, whereby a form incorporating said device can be separated from a concrete structure cast thereagainst by engaging an actuating unit with said hollow bushing and driving the ram head thereof through the bushing to exert pressure on the concrete structure.
Claim 3
Dependent Claim
36 words
A device as claimed in claim 1, wherein said reaction plate is formed with holes for the passage of fastening means into the form, whereby rotation of the device relative to the form can be prevented.
Claim 4
Dependent Claim
37 words
A device as claimed in claim 1, wherein said reaction plate is formed with peripheral notches for the passage of fastening means into the form, whereby rotation of the device relative to the form can be prevented.
Claim 5
Dependent Claim
43 words
A device as claimed in claim 1, wherein the outer surface of the reaction plate is dome-shaped and said reaction plate is formed with projections on said outer surface for contact with the concrete during casting whereby rotation of the plate is prevented.
Claim 6
Dependent Claim
37 words
A device as claimed in claim 1, wherein the reaction plate includes retainer pins on the surface for engagement with the form, whereby said pins can be driven into the form to prevent rotation of the plate.
Claim 7
Dependent Claim
35 words
A device as claimed in claim 1, wherein the reaction plate is of non circular configuration for recessing into flush relation with the concrete forming surface of the form to prevent rotation of the device.
Claim 8
Dependent Claim
36 words
A device as claimed in claim 1, and further comprising a flange on said plug for engagement in the aperture in said reaction plate to prevent the ingress of concretE into said hollow bushing during pouring.
Claim 9
Dependent Claim
48 words
A device as claimed in claim 7, wherein said reaction plate is formed with a peripheral recess around said aperture for cooperating engagement with the flange of the plug, whereby the surface of a plug engaged in the aperture is substantially flush with the surface of the plate.
Claim 10
Dependent Claim
44 words
A device as claimed in claim 1, wherein said engagement means comprises an internal thread formed in said bushing, and wherein said actuating unit comprises a threaded bolt engageable in said hollow bushing with the leading end of the bolt constituting said ram head.
Claim 11
Dependent Claim
83 words
A device as claimed in claim 1, wherein said engagement means comprises an internal thread formed in said bushing, said actuating unit comprises a cylinder having an externally screw threaded and open ended neck at one end for screwed engagement with the hollow bushing and an inlet for a pressure fluid at the other end, a piston movable within the cylinder, and a piston rod extending from said cylinder and through said neck, the end of the piston rod constituting said ram head.
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) | 1977-09-23 | 1978-03-25 | 1978-09-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-09-23 | 1982-03-25 | 1982-09-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-09-23 | 1986-03-25 | 1986-09-24 | $7700.00 | Window Closed / Lapsed |