Agitating – Rubber or heavy plastic working – Stirrer is through-pass screw conveyor
Reexamination Certificate
1999-07-15
2001-08-07
Cooley, Charles E. (Department: 1723)
Agitating
Rubber or heavy plastic working
Stirrer is through-pass screw conveyor
Reexamination Certificate
active
06270245
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to an extrusion machine barrel, as well as a liner for such an extrusion machine barrel.
The invention applies particularly to extruders which have at least two screws, and more generally to extrusion machines in which mixing, kneading, comminuting, reaction, drawing-out, baking and in particular shearing effects are introduced by passing through the barrel a substance that is carried along by the rotation of the screws.
BACKGROUND OF THE INVENTION
In general, an extrusion machine comprises a barrel of elongate shape equipped with a bore extending along the entire length of the said barrel and in which there is a liner that envelops the screws.
When the extrusion machine comprises two parallel-axis screws, the liner comprises two parallel-axis cylindrical bores in which the screws are placed, and these screws may or may not intermesh.
The screws are fitted on their periphery with, in particular, helically-wound flights which carry in a downstream direction the substance which is introduced via an upstream end of the barrel.
The substance is thus carried along as far as the downstream end of the barrel, which may be fitted with an extrusion die or alternatively simply have an outlet orifice if the substance is not to be subjected to an extrusion operation.
In order to vary the treatment to be carried out as the substance progresses along the barrel, the screws generally consist of successive regions which have flights of different shape or pitch or which comprise specific treatment members.
Until now, the bore in the barrel was obtained by making two secant drillings which form two longitudinal ribs where they intersect and by machining these longitudinal ribs to obtain a flat surface between the two drillings so as to produce a bore formed of two half lobes joined by flat portions.
This technique therefore requires a number of machining tools, particularly a boring machine for the drillings and a milling machine to produce the flat surfaces.
Furthermore, it is necessary when performing the stage of grinding the bore of the barrel, to use special-purpose tools of special shape, given that this bore is formed of a series of curved portions and flat portions.
These various operations and the change of tooling for each of these operations significantly increases the cost of the barrel and the time taken to machine the bore in the barrel.
SUMMARY OF THE INVENTION
The object of the invention is to overcome these drawbacks by providing an extrusion machine barrel which is easier to machine and allows a reduction in manufacturing lead time.
The subject of the invention is a barrel of an extrusion machine comprising a bore having three lubes and begin intended to take a liner in which at least two parallel-axis screws are rotated.
According to other features of the invention:
the lobes of the bore are formed by three secant drillings, the axes of which are mutually parallel and lie in the same plane as the main axis of the barrel, the axis of one of the drillings lying on the main axis and the axes of the other two drillings being located on either side of and equidistant from this main axis,
the first drilling is made on the main axis of the barrel and the second and third drillings are made one on each side of and secant with the first drilling, the diameters of these drillings being roughly equal,
the first drilling is made on one side of and at a given distance from the main axis of the barrel the second drilling is made on the other side of the main axis and the same distance away from the main axis of the barrel and the third drilling is made on this main axis, the drillings being secant and the diameters of the drillings being roughly equal,
the axes of the drillings arranged on either side of the drilling that lies on the main axis of the barrel lie inside the circumference delimited by the drilling that is arranged on the main axis,
the axes of the drillings that are arranged on either side of the drilling that lies on the main axis of the barrel lie on the circumference delimited by the drilling that is arranged on the main axis,
the axes of the drillings arranged on either side of the drilling that is arranged on the main axis of the barrel lie outside the circumference delimited by the drilling that is arranged on the main axis,
the drillings are made by a boring machine or a drilling machine.
Another subject of the invention is an extrusion machine barrel liner in which at least two parallel-axis screws are rotated, the outer face of the liner being formed by three lobes and comprising two parallel-axis secant bores.
REFERENCES:
patent: 2508495 (1950-05-01), Consalvo
patent: 2550226 (1951-04-01), Colombo
patent: 3268949 (1966-08-01), Schmidt et al.
patent: 3590429 (1971-07-01), Bammert et al.
patent: 3696736 (1972-10-01), Studli
patent: 3704866 (1972-12-01), Mosher et al.
patent: 3900188 (1975-08-01), Seufert
patent: 3910316 (1975-10-01), Reifenhauser
patent: 3927869 (1975-12-01), Hanslik
patent: 3970113 (1976-07-01), Guttinger et al.
patent: 4028027 (1977-06-01), Worz
patent: 4036540 (1977-07-01), Seufert
patent: 4117583 (1978-10-01), Gnadig et al.
patent: 4364664 (1982-12-01), Theysohn
patent: 4385876 (1983-05-01), Scherping et al.
patent: 4590033 (1986-05-01), Chapet
patent: 5093209 (1992-03-01), Kroisenbrunner
patent: 5116135 (1992-05-01), Kaiser et al.
patent: 5209937 (1993-05-01), Kangas
patent: 5352539 (1994-10-01), Psiuk
patent: 5752770 (1998-05-01), Kawaguchi et al.
patent: 5816699 (1998-10-01), Keith et al.
patent: 319 489 A (1920-03-01), None
patent: 513431 (1992-11-01), None
patent: 0 642 861 A (1995-03-01), None
patent: 889 063 A (1943-12-01), None
Schaefer, R.T., et al., “Slot Drilling: Eliminating the Trade-Offs,” Printed Circuit Fabrication, vol. 15, No. 10, Oct. 1992, San Francisco, U.S., pp. 40-41, X0000311270.
IBM Technical Disclosure Bulletin, vol., 37, No. 06b, Jun. 1984, New York, US, p. 661, XP002035366 “Dynamic Control Method and Apparatus for Drill Machines”.
Patent Abstracts of Japan, vol. 9, No. 303 (M-434) [2026], Nov. 30, 1985, and JP 60 141411 A (Hitachi Kasei), Jul. 26, 1985.
Bruyas Laurent
Chenevier Daniel
Maisonny Serge
Clextral
Connolly Bove & Lodge & Hutz LLP
Cooley Charles E.
LandOfFree
Extrusion machine barrel having a three-lobe bore, and liner... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Extrusion machine barrel having a three-lobe bore, and liner..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Extrusion machine barrel having a three-lobe bore, and liner... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2522524