Patent US3826411A successfully refreshed from Google Patents.
US3826411A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Concrete slab forming machine with high extrusion capacity
Assignee: Individual
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Filing: 1973-01-26
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Granted: 1974-07-30
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Expires: 1993-01-26
Abstract
Abstract During a ram stroke, a ram plate forces a concrete mix from a ram chamber into a slab forming cavity and a gate member closes to isolate the ram chamber from a supply hopper. The supply hopper includes a rotary feeder having a hypocycloid cross section for transporting the concrete mix through the hopper to the ram chamber.
Inventors
- 👤 A Kalns
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 03:06
CPC Classifications
B; B28; B28B; B28B3/00; B28B3/20; B28B3/24
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
153 words
In a concrete extrusioN machine of the type in which a concrete mix is fed from a hopper by a feeder mounted on an axle in the hopper to a ram chamber during the retraction of a ram plate, the ram plate being moved during a ram stroke from its retracted position through the chamber to force at least a portion of the concrete mix into an extrusion cavity, the hopper communicating with the ram chamber through an opening therebetween, the improvement comprising: a movable closure member for said opening, the closure member including a blade disposed within the hopper for swingable movement therein and an operating arm pivotally supported by said axle, the blade being secured at one end to the operating arm, and means responsive to a ram stroke to pivot the operating arm so that the blade at least partially closes the opening during a portion of the ram stroke.
Claim 2
Dependent Claim
153 words
In a concrete extrusioN machine of the type in which a concrete mix is fed from a hopper by a feeder mounted on an axle in the hopper to a ram chamber during the retraction of a ram plate, the ram plate being moved during a ram stroke from its retracted position through the chamber to force at least a portion of the concrete mix into an extrusion cavity, the hopper communicating with the ram chamber through an opening therebetween, the improvement comprising: a movable closure member for said opening, the closure member including a blade disposed within the hopper for swingable movement therein and an operating arm pivotally supported by said axle, the blade being secured at one end to the operating arm, and means responsive to a ram stroke to pivot the operating arm so that the blade at least partially closes the opening during a portion of the ram stroke.
Claim 3
Dependent Claim
18 words
A machine as defined in claim 1 wherein said hopper mounted feeder has a generally hypocycloid cross section.
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) | 1977-07-29 | 1978-01-28 | 1978-07-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-07-29 | 1982-01-28 | 1982-07-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-07-29 | 1986-01-28 | 1986-07-30 | $7700.00 | Window Closed / Lapsed |