DE4021550A1 - Double screw extrusion of plastics without compression increase - with inward tapering screw with increasing pitch but decreasing channel depth which retains constant vol. between adjacent flights - Google Patents

Double screw extrusion of plastics without compression increase - with inward tapering screw with increasing pitch but decreasing channel depth which retains constant vol. between adjacent flights

Info

Publication number
DE4021550A1
DE4021550A1 DE4021550A DE4021550A DE4021550A1 DE 4021550 A1 DE4021550 A1 DE 4021550A1 DE 4021550 A DE4021550 A DE 4021550A DE 4021550 A DE4021550 A DE 4021550A DE 4021550 A1 DE4021550 A1 DE 4021550A1
Authority
DE
Germany
Prior art keywords
screw
rib
plastics
slope
channel depth
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
DE4021550A
Other languages
German (de)
Inventor
Dieter Ing Stricker
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Cincinnati Milacron Austria GmbH
Original Assignee
Cincinnati Milacron Austria GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Cincinnati Milacron Austria GmbH filed Critical Cincinnati Milacron Austria GmbH
Publication of DE4021550A1 publication Critical patent/DE4021550A1/en
Withdrawn legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
    • B29C48/395—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die using screws surrounded by a cooperating barrel, e.g. single screw extruders
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
    • B29C48/395—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die using screws surrounded by a cooperating barrel, e.g. single screw extruders
    • B29C48/40—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die using screws surrounded by a cooperating barrel, e.g. single screw extruders using two or more parallel screws or at least two parallel non-intermeshing screws, e.g. twin screw extruders
    • B29C48/402—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die using screws surrounded by a cooperating barrel, e.g. single screw extruders using two or more parallel screws or at least two parallel non-intermeshing screws, e.g. twin screw extruders the screws having intermeshing parts
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
    • B29C48/50—Details of extruders
    • B29C48/505—Screws
    • B29C48/52—Screws with an outer diameter varying along the longitudinal axis, e.g. for obtaining different thread clearance
    • B29C48/525—Conical screws
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion

Abstract

A screw, in partic. a double screw for a plastics extruder has at least one spiral form screw flight. Both the outer dia. and the core dia. are tapered inward from the inlet end to the outlet end of the screw and the channel depth changes. Increased compression of the molten polymer can be avoided if the screw pitch changes continuously, at least in the output region, while the volume of the channel between adjacent screw flights remains fixed.

Description

Die Erfindung bezieht sich auf eine Schnecke, insbesondere Doppelschnecke, für eine Schneckenstrangpresse zum Verarbeiten von Kunststoffen, mit mindestens einer im wesentlichen gewin­ deartig verlaufenden Rippe, wobei der Außendurchmesser und der Kerndurchmesser der Schnecke vom einzugseitigen zum ausstoß­ seitigen Ende hin verjüngt sind und bei der sich die Gangtiefe verändert.The invention relates to a snail, in particular Double screw, for an extrusion screw press for processing of plastics, with at least one essentially winning such a running rib, the outer diameter and the Core diameter of the screw from the feed side to the discharge side end are tapered and at which the aisle depth changed.

Bekannte derartige Schnecken weisen eine konstante Steigung der Rippe(n) auf. Dies führt in Verbindung mit der sich än­ dernden Gangtiefe zu einer sich steigernden Verdichtung der plastischen Masse, da sich die Volumina von Lücke zu Lücke vermindern. Diese sich erhöhende Verdichtung der Masse führt zu einer erhöhten Friktion und damit zu einer Erhöhung der Temperatur, die unerwünscht ist.Known such screws have a constant slope the rib (s). This leads in connection with the change changing aisle depth to an increasing compression of the plastic mass, since the volumes vary from gap to gap Reduce. This increasing compression of the mass leads to increased friction and thus to an increase in Temperature that is undesirable.

Ziel der Erfindung ist es diese Nachteile zu vermeiden und eine Schnecke der eingangs erwähnten Art vorzuschlagen, bei der eine Erhöhung der Verdichtung im Ausstoßbereich der Schnecke vermieden ist.The aim of the invention is to avoid these disadvantages and to propose a snail of the type mentioned at the beginning which increases the compression in the discharge area of the Snail is avoided.

Erfindungsgemäß wird dies dadurch erreicht, daß sich die Stei­ gung der Rippe zumindest über die Länge der Ausstoßzone konti­ nuierlich ändert, wobei die Volumina der Lücken zwischen benachbarten Windungen der Rippe(n) konstant bleiben.According to the invention this is achieved in that the Stei rib at least over the length of the discharge zone nuously changes, with the volumes of the gaps between neighboring turns of the rib (s) remain constant.

Durch diese Maßnahmen wird sichergestellt, daß sich die Breite der Rippe(n) über die Länge zumindest der Ausstoßzone ändert, wodurch es eben möglich ist, daß trotz der sich ändernden Gangtiefe die Volumina gleich bleiben und wodurch eine Erhö­ hung der Verdichtung des plastischen Materials vermieden wird.These measures ensure that the width the rib (s) changes over the length of at least the discharge zone, which makes it possible that despite the changing Depth the volumes remain the same and thus an increase The compression of the plastic material is avoided.

Nach einem weiteren Merkmal der Erfindung kann vorgesehen sein, daß die Steigung der Rippe(n) einen degressiven Verlauf aufweist.According to a further feature of the invention can be provided be that the slope of the rib (s) has a degressive course having.

Auf diese Weise kommt es zu einer Abnahme der Breiten der Rippe(n), wodurch die Volumina der Lücken gleich gehalten wer­ den kann. Grundsätzlich kann die Steigung aber auch einen be­ liebigen nichtlinearen Verlauf aufweisen, um das gerade not­ wendige zu fördernde Volumen zu beherrschen.In this way there is a decrease in the widths of the Rib (s), which keeps the volume of the gaps the same  that can. Basically, the slope can also be a have a non-linear course, just to be precise to master maneuverable volumes to be funded.

Nach einem weiteren Merkmal der Erfindung kann vorgesehen sein, daß sich die Steigung der Rippe(n) über die gesamte Länge der Schnecke kontinuierlich ändert.According to a further feature of the invention can be provided be that the slope of the rib (s) over the entire Length of the screw changes continuously.

Dadurch können die Entgasungszone und die Ausstoßzone der Schnecke in einem ausgeführt werden. Außerdem ist es dadurch auch möglich längs der Schnecke durch kontinuierliche Änderung der Steigung Zonen zu schaffen, in welchen bestimmte Volumina gefördert werden. Es können daher Volumsförderprofile längs der Schnecke in beliebiger Art gestaltet werden. Damit ist eine optimale Anpassung an die zu verarbeitende plastische Masse und den jeweilig herzustellenden Gegenständen möglich.This allows the degassing zone and the discharge zone of the Snail run in one. It is also because of it also possible along the screw through continuous change the slope to create zones in which certain volumes be promoted. There can therefore be volume conveying profiles lengthways the snail can be designed in any way. So that is an optimal adaptation to the plastic to be processed Mass and the respective objects to be manufactured possible.

Die Erfindung wird nun anhand der Zeichnung näher erläutert. Dabei zeigt:The invention will now be explained in more detail with reference to the drawing. It shows:

Fig. 1 einen Ausschnitt aus einer bekannten Schnecke, Fig. 1 shows a portion of a known screw,

Fig. 2 einen Ausschnitt aus einer erfindungsgemäßen Schnecke. Fig. 2 shows a section of a snail according to the invention.

Fig. 3 und 4 zwei Beispiele von erfindungsgemäßen Schnecken in Ansicht, und die FIGS. 3 and 4, two examples of the inventive screw in view, and the

Fig. 3a und 4a die zu den Schnecken gemäß den Fig. 3 und 4 gehörenden Volumsdiagramme. FIGS. 3a and 4a to the screw according to FIGS. 3 and 4 belonging Volumsdiagramme.

Wie aus der Fig. 1 zu ersehen ist, weist die bekannte Schnecke einen konisch verlaufenden Außendurchmesser und einen konisch verlaufenden Kerndurchmesser auf. Die Steigung s der Rippe 1 ist bei der bekannten Schnecke konstant. Aus diesem Grund bleibt die Breite b der Rippe 1 konstant. Da sich die Gang­ tiefe h ändert, ändert sich auch das Volumen der Lücken zwi­ schen den jeweils benachbarten Windungen der Rippe 1. Dies führt zu einer entsprechenden Erhöhung der Verdichtung der durch die Lücken fließenden plastischen Masse.As can be seen from FIG. 1, the known screw has a tapered outer diameter and a tapered core diameter. The slope s of the rib 1 is constant in the known screw. For this reason, the width b of the rib 1 remains constant. Since the depth h changes, the volume of the gaps between the adjacent turns of the rib 1 also changes . This leads to a corresponding increase in the compression of the plastic mass flowing through the gaps.

Die Fig. 2 zeigt einen entsprechenden Ausschnitt aus einer er­ findungsgemäßen Schnecke. Diese weist ebenfalls einen konisch verlaufenden Außendurchmesser und einen konisch verlaufenden Kerndurchmesser auf. Dabei weist aber die Rippe 1 eine sich ändernde Steigung s auf. Dies führt zu einer sich ändernden Breite b der Rippe. Durch diese Änderung der Rippenbreite kann die sich ebenfalls ändernde Gangtiefe h ausgeglichen werden, sodaß der Querschnitt der Lücken zwischen benachbarten Windun­ gen der Rippe 1 gleich bleibt. Damit wird eine Erhöhung der Verdichtung der plastischen Masse vermieden. Fig. 2 shows a corresponding section of an inventive screw it. This also has a tapered outer diameter and a tapered core diameter. Here, however, the rib 1 has a changing slope s. This leads to a changing width b of the rib. This change in the width of the ribs can also compensate for the changing pitch h, so that the cross section of the gaps between adjacent windings of the rib 1 remains the same. This avoids an increase in the compression of the plastic mass.

Die Fig. 3 und 4 zeigen verschiedene Ausführungsformen von er­ findungsgemäßen Schnecken bei denen, wie die jeweils zugehöri­ gen Volumsdiagramme (Fig. 3a und 4a), in denen die Volumina der Lücken über die Länge der Schnecke aufgetragen ist, die Volumina im Bereich der Ausstoßzone 12 konstant bleiben. Dies wird durch eine kontinuierliche Änderung der Steigung der Rippe 1 erreicht, wodurch der Einfluß des sich verjüngenden Außen- und Kerndurchmessers der Schnecke 10 in diesem Bereich ausgeglichen wird. FIGS. 3 and 4 show different embodiments of he inventive screw in which, as the related contractual each Volumsdiagramme (Fig. 3a and 4a) in which the volumes of the gaps is applied over the length of the screw, the volumes in the range of the ejection zone 12 remain constant. This is achieved by continuously changing the slope of the rib 1 , as a result of which the influence of the tapering outer and core diameter of the screw 10 is compensated for in this area.

Bei der Ausführungsform nach der Fig. 3 ist im einzugseitigen Bereich 11 der Schnecke 10 eine konstante Steigung der Rippe 1 vorgesehen, wodurch sich eine konstant bleibende Änderung der Volumina der Lücke ergibt, wie aus dem Volumsdiagramm gemäß Fig. 3a zu ersehen ist. Im Übergangsbereich zum ausstoßsei­ tigen Endbereich 12 ist ein Bereich vorgesehen, in dem die Rippe 1 unterbrochen ist und sich das Volumen der Lücke abrupt ändert.In the embodiment according to FIG. 3, a constant slope of the rib 1 is provided in the feed-in region 11 of the screw 10 , which results in a constant change in the volume of the gap, as can be seen from the volume diagram according to FIG. 3a. In the transition area to the end portion 12 on the ejection side, an area is provided in which the rib 1 is interrupted and the volume of the gap changes abruptly.

Bei der Ausführungsform nach der Fig. 4 ist im einzugseitigen Endbereich eine sich ändernde Steigung vorgesehen. Dies führt zu entsprechenden Änderungen der Volumina der Lücken, wie aus Fig. 4a zu ersehen ist. Somit kann durch entsprechende Wahl der Steigung in den einzelnen Abschnitten der Schnecke ein be­ liebiges Pofil der Volumina der Lücken der Schnecke 10 und so­ mit des Fördervolumens in den einzelnen Bereichen erreicht werden.In the embodiment according to FIG. 4, a changing slope is provided in the end region on the intake side. This leads to corresponding changes in the volumes of the gaps, as can be seen from FIG. 4a. Thus, by appropriate choice of the slope in the individual sections of the screw, an arbitrary profile of the volumes of the gaps of the screw 10 and thus the delivery volume in the individual areas can be achieved.

Claims (3)

1. Schnecke, insbesondere Doppelschnecke, für eine Schnecken­ strangpresse zum Verarbeiten von Kunststoffen, mit minde­ stens einer im wesentlichen gewindeartig verlaufenden Rippe, wobei der Außendurchmesser und der Kerndurchmesser der Schnecke vom einzugseitigen zum ausstoßseitigen Ende hin verjüngt sind und bei der sich die Gangtiefe verän­ dert, dadurch gekennzeichnet, daß sich die Steigung (h) der Rippe (1) zumindest über die Länge der Ausstoßzone kontinuierlich ändert, wobei die Volumina der Lücken zwi­ schen benachbarten Windungen der Rippe(n) (1) konstant bleiben.1. Screw, in particular twin screw, for a screw extruder for processing plastics, with at least at least one essentially thread-like rib, the outer diameter and the core diameter of the screw being tapered from the feed end to the discharge end and at which the flight depth changes , characterized in that the slope (h) of the rib ( 1 ) changes continuously over at least the length of the discharge zone, the volumes of the gaps between adjacent turns of the rib (s) ( 1 ) remaining constant. 2. Schnecke nach Anspruch 1, dadurch gekennzeichnet, daß die Steigung (s) der Rippe(n) (1) einen degressiven Verlauf aufweist. 2. Snail according to claim 1, characterized in that the slope (s) of the rib (s) ( 1 ) has a degressive course. 3. Schnecke nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß sich die Steigung (s) der Rippe(n) (1) über die ge­ samte Länge der Schnecke kontinuierlich ändert.3. Screw according to claim 1 or 2, characterized in that the slope (s) of the rib (s) ( 1 ) changes continuously over the entire length of the screw.
DE4021550A 1989-07-12 1990-07-09 Double screw extrusion of plastics without compression increase - with inward tapering screw with increasing pitch but decreasing channel depth which retains constant vol. between adjacent flights Withdrawn DE4021550A1 (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
AT0169289A AT401156B (en) 1989-07-12 1989-07-12 SNAIL, ESPECIALLY DOUBLE SNAIL, FOR AN EXTRACTION PRESS FOR THE PROCESSING OF PLASTICS

Publications (1)

Publication Number Publication Date
DE4021550A1 true DE4021550A1 (en) 1991-01-24

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DE4021550A Withdrawn DE4021550A1 (en) 1989-07-12 1990-07-09 Double screw extrusion of plastics without compression increase - with inward tapering screw with increasing pitch but decreasing channel depth which retains constant vol. between adjacent flights

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AT (1) AT401156B (en)
DE (1) DE4021550A1 (en)

Cited By (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0596835A1 (en) * 1992-11-03 1994-05-11 Illinois Institute Of Technology Solid state shear extrusion pulverization
US5395055A (en) * 1992-11-03 1995-03-07 Illinois Institute Of Technology Solid state shear extrusion pulverization
US5397065A (en) * 1992-11-03 1995-03-14 Illinois Institute Of Technology Solid state shear extrusion pulverization
US5415354A (en) * 1992-11-03 1995-05-16 Illinois Institute Of Technology Solid state shear extrusion pulverization
EP0744269A2 (en) * 1995-05-24 1996-11-27 American Maplan Corp. Double-screw extruder
US5704555A (en) * 1993-08-02 1998-01-06 Illinois Institute Of Technology Single-screw extruder for solid state shear extrusion pulverization and method
US5743471A (en) * 1993-08-02 1998-04-28 Illinois Institute Of Technology Solid state shear extrusion pulverization
US5871486A (en) * 1993-01-21 1999-02-16 Acumed, Inc. Variable pitch bone screw
EP0927622A1 (en) * 1997-11-13 1999-07-07 Gebrüder Kömmerling Kunststoffwerke GmbH Twin screw extruder
US5964768A (en) * 1993-01-21 1999-10-12 Acumed, Inc. Tapered bone screw with continuously varying pitch
US6030162A (en) * 1998-12-18 2000-02-29 Acumed, Inc. Axial tension screw
US6299615B1 (en) 1993-01-21 2001-10-09 Acumed, Inc. System for fusing joints
US6468277B1 (en) 2000-04-04 2002-10-22 Ethicon, Inc. Orthopedic screw and method
US6984235B2 (en) 1993-01-21 2006-01-10 Acumed Llc System for fusing joints
DE102010003601A1 (en) * 2010-04-01 2011-10-06 Frank Börner Twin-screw extruder and process for thermomechanical digestion of organic raw materials and residues
US8070786B2 (en) 1993-01-21 2011-12-06 Acumed Llc System for fusing joints
US9161793B2 (en) 1993-01-21 2015-10-20 Acumed Llc Axial tension screw

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3939578A (en) * 1973-06-20 1976-02-24 Elizabeth Jane Putnam Coffey Educational board game apparatus

Citations (4)

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Publication number Priority date Publication date Assignee Title
US2466934A (en) * 1946-01-05 1949-04-12 Charles E Dellenbarger Extruding machine for plastic material
GB632364A (en) * 1944-03-29 1949-11-28 Lavorazione Mat Plast Screw press for mixing and extruding synthetic plastic materials, more particularly thermoplastic materials
US4408888A (en) * 1980-11-10 1983-10-11 American Maplan Corporation Double-worm extrusion press
AT376397B (en) * 1982-12-21 1984-11-12 Cincinnati Milacron Austria SCREW EXTRUSION PRESS

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US3470584A (en) * 1965-11-30 1969-10-07 Sekisui Chemical Co Ltd Extruder for shaping powdery thermoplastic resins
US3518721A (en) * 1966-03-29 1970-07-07 Vasily Alexandrovich Rukas Screw extruder for reprocessing thermoplastics

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB632364A (en) * 1944-03-29 1949-11-28 Lavorazione Mat Plast Screw press for mixing and extruding synthetic plastic materials, more particularly thermoplastic materials
US2466934A (en) * 1946-01-05 1949-04-12 Charles E Dellenbarger Extruding machine for plastic material
US4408888A (en) * 1980-11-10 1983-10-11 American Maplan Corporation Double-worm extrusion press
AT376397B (en) * 1982-12-21 1984-11-12 Cincinnati Milacron Austria SCREW EXTRUSION PRESS

Cited By (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0596835A1 (en) * 1992-11-03 1994-05-11 Illinois Institute Of Technology Solid state shear extrusion pulverization
US5395055A (en) * 1992-11-03 1995-03-07 Illinois Institute Of Technology Solid state shear extrusion pulverization
US5397065A (en) * 1992-11-03 1995-03-14 Illinois Institute Of Technology Solid state shear extrusion pulverization
US5415354A (en) * 1992-11-03 1995-05-16 Illinois Institute Of Technology Solid state shear extrusion pulverization
US6984235B2 (en) 1993-01-21 2006-01-10 Acumed Llc System for fusing joints
US8070786B2 (en) 1993-01-21 2011-12-06 Acumed Llc System for fusing joints
US5871486A (en) * 1993-01-21 1999-02-16 Acumed, Inc. Variable pitch bone screw
US5964768A (en) * 1993-01-21 1999-10-12 Acumed, Inc. Tapered bone screw with continuously varying pitch
US6299615B1 (en) 1993-01-21 2001-10-09 Acumed, Inc. System for fusing joints
US9161793B2 (en) 1993-01-21 2015-10-20 Acumed Llc Axial tension screw
US5704555A (en) * 1993-08-02 1998-01-06 Illinois Institute Of Technology Single-screw extruder for solid state shear extrusion pulverization and method
US5743471A (en) * 1993-08-02 1998-04-28 Illinois Institute Of Technology Solid state shear extrusion pulverization
EP0744269A3 (en) * 1995-05-24 1997-09-10 American Maplan Corp Double-screw extruder
EP0744269A2 (en) * 1995-05-24 1996-11-27 American Maplan Corp. Double-screw extruder
EP0927622A1 (en) * 1997-11-13 1999-07-07 Gebrüder Kömmerling Kunststoffwerke GmbH Twin screw extruder
US6030162A (en) * 1998-12-18 2000-02-29 Acumed, Inc. Axial tension screw
US6468277B1 (en) 2000-04-04 2002-10-22 Ethicon, Inc. Orthopedic screw and method
US7578836B2 (en) 2000-04-04 2009-08-25 Depuy Mitek Orthopedic screw and method
US6989014B2 (en) 2000-04-04 2006-01-24 Ethicon, Inc. Orthopedic screw and method
US6527777B2 (en) 2000-04-04 2003-03-04 Ethicon, Inc. Device for repairing a soft-tissue tear and method
DE102010003601A1 (en) * 2010-04-01 2011-10-06 Frank Börner Twin-screw extruder and process for thermomechanical digestion of organic raw materials and residues
EP2371525A3 (en) * 2010-04-01 2011-12-07 Börner, Frank Twin screw extruder and method for the thermo-mechanical pulping of organic raw and residual materials
DE102010003601B4 (en) * 2010-04-01 2015-05-13 Frank Börner Twin-screw extruder

Also Published As

Publication number Publication date
ATA169289A (en) 1995-11-15
AT401156B (en) 1996-07-25

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