Patent US3577935A successfully refreshed from Google Patents.
US3577935A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Extrusion apparatus
Assignee: General Mills Inc
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Filing: 1967-02-01
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Granted: 1971-05-11
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Expires: 1987-02-01
Abstract
Abstract An apparatus and method for extruding an elongated, tubular, corrugated product having a plurality of longitudinally extending indentations or depressions on its surface. Extrudable material is forced through an extrusion apparatus having an annular extrusion orifice formed by a die opening in the extrusion apparatus, and a mandrel having its projecting end positioned in the opening. Either the shape of the die opening or the shape of the mandrel is formed in such a manner that the thickness of the space surrounding the mandrel varies at a number of different points. A product made by using this apparatus has a somewhat coblike appearance.
Inventors
- 👤 Richard D Reinhart
- 👤 Robert O Straughn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:29
CPC Classifications
A; A21; A21C; A21C11/00; A21C11/16; A23; A23P; A23P30/00; A23P30/20
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
155 words
An extrusion apparatus for forming a tubular corrugated extrudate comprising a die housing provided with a die chamber therein which terminates with a die opening having a prescribed shape, said die opening being formed by a cylindrical bore, an elongated mandrel within the die chamber, means for positioning said mandrel within said chamber so that one of its ends projects through said die opening, said mandrel end having a substantially cylindrical cross-sectional shape which is smaller than the cross-sectional shape of the die opening thereby defining a peripheral space surrounding said mandrel end which varies in thickness at a number of different points as it surrounds the mandrel, the surface of the mandrel end being provided with a plurality of equidistantly spaced-apart grooves which extend parallel to the longitudinal axis of the mandrel, adjacent grooves being separated by land portions, said land portions having a narrower peripheral width than the peripheral width of the grooves.
Claim 2
Dependent Claim
155 words
An extrusion apparatus for forming a tubular corrugated extrudate comprising a die housing provided with a die chamber therein which terminates with a die opening having a prescribed shape, said die opening being formed by a cylindrical bore, an elongated mandrel within the die chamber, means for positioning said mandrel within said chamber so that one of its ends projects through said die opening, said mandrel end having a substantially cylindrical cross-sectional shape which is smaller than the cross-sectional shape of the die opening thereby defining a peripheral space surrounding said mandrel end which varies in thickness at a number of different points as it surrounds the mandrel, the surface of the mandrel end being provided with a plurality of equidistantly spaced-apart grooves which extend parallel to the longitudinal axis of the mandrel, adjacent grooves being separated by land portions, said land portions having a narrower peripheral width than the peripheral width of the grooves.
Claim 3
Dependent Claim
138 words
An extrusion apparatus for forming a tubular corrugated extrudate comprising a die housing provided with a die chamber therein which terminates with a die opening having a prescribed shape, an elongated mandrel within the die chamber, means for positioning said mandrel within said chamber so that one of its ends projects into said die opening, said mandrel end having a cross-sectional shape which differs from and is smaller than the cross-sectional shape of the die opening thereby defining a peripheral space surrounding said mandrel end which varies in thickness at a number of different points as it surrounds the mandrel, and a flexible tube of predetermined length which is secured to the projecting end of the mandrel, the cross-sectional shape and size of said tube being substantially the same as the size and shape of said mandrel end.
Claim 4
Dependent Claim
138 words
An extrusion apparatus for forming a tubular corrugated extrudate comprising a die housing provided with a die chamber therein which terminates with a die opening having a prescribed shape, an elongated mandrel within the die chamber, means for positioning said mandrel within said chamber so that one of its ends projects into said die opening, said mandrel end having a cross-sectional shape which differs from and is smaller than the cross-sectional shape of the die opening thereby defining a peripheral space surrounding said mandrel end which varies in thickness at a number of different points as it surrounds the mandrel, and a flexible tube of predetermined length which is secured to the projecting end of the mandrel, the cross-sectional shape and size of said tube being substantially the same as the size and shape of said mandrel end.
Claim 5
Dependent Claim
38 words
The combination of claim 2 wherein the mandrel is provided with a passage therein which extends parallel to the longitudinal axis of the mandrel, said passage providing a conduit for discharging a gaseous medium into the tubular extrudate.
Claim 6
Dependent Claim
129 words
An extrusion apparatus for forming a tubular corrugated extrudate comprising a die housing provided with a die chamber therein which terminates with a die opening having a prescribed shape, an elongated mandrel within the die chamber, means for positioning said mandrel within said chamber so that one of its ends projects into said die opening, said mandrel end having a cross-sectional shape which differs from and is smaller than the cross-sectional shape of the die opening thereby defining a peripheral space surrounding said mandrel end which varies in thickness at a number of different points as it surrounds the mandrel, and stationary means are provided externally of the die chamber for restraining the free flow of the extrudate through the extrusion orifice thereby providing lateral corrugations in the extrudate.
Claim 7
Dependent Claim
129 words
An extrusion apparatus for forming a tubular corrugated extrudate comprising a die housing provided with a die chamber therein which terminates with a die opening having a prescribed shape, an elongated mandrel within the die chamber, means for positioning said mandrel within said chamber so that one of its ends projects into said die opening, said mandrel end having a cross-sectional shape which differs from and is smaller than the cross-sectional shape of the die opening thereby defining a peripheral space surrounding said mandrel end which varies in thickness at a number of different points as it surrounds the mandrel, and stationary means are provided externally of the die chamber for restraining the free flow of the extrudate through the extrusion orifice thereby providing lateral corrugations in the extrudate.
Claim 8
Dependent Claim
21 words
The combination of claim 4 wherein the mandrel end projects through the die opening and terminates exteriorly oF the die chamber.
Claim 9
Dependent Claim
51 words
The combination of claim 4 wherein the die opening is formed by a cylindrical bore and the mandrel end is substantially cylindrically shaped, the surface of at least one of the cylindrically shaped members being provided with a plurality of grooves which extend parallel to the longitudinal axis of the mandrel.
Claim 10
Dependent Claim
40 words
The combination of claim 6 wherein said grooves are equidistantly spaced about the periphery of the mandrel, and adjacent grooves are separated by land portions, said land portions having a narrower peripheral width than the peripheral width of the grooves.
Claim 11
Dependent Claim
19 words
The combination of claim 6 wherein the grooves and lands are formed on the surface of the cylindrical bore.
Claim 12
Dependent Claim
23 words
The combination of claim 4 wherein the die opening has a circular cross-sectional shape, and the mandrel end has a polygonal cross-sectional shape.
Claim 13
Dependent Claim
31 words
The combination of claim 4 wherein the mandrel end projects through the die opening, and said means includes at least one ring-shaped member positioned on the mandrel proximate its projecting end.
Claim 14
Dependent Claim
51 words
The combination of claim 4 wherein said restraining means includes a tubular cowling, means for attaching said cowling to the die housing so that it is aligned with the die chamber and the die opening, the internal cross-sectional size of said cowling being larger than cross-sectional size of the die opening.
Claim 15
Dependent Claim
22 words
The combination of claim 11 wherein at least one passage is formed in the cowling for admitting pressurized air into said cowling.
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) | 1974-05-10 | 1974-11-09 | 1975-05-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-10 | 1978-11-09 | 1979-05-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-10 | 1982-11-09 | 1983-05-11 | $7700.00 | Window Closed / Lapsed |