US3762693A
Expired / Lapsed
US
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Methods of and apparatus for advancing and working thermoplastic materials
Assignee: AT&T Inc
•
Filing: 1971-04-13
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Granted: 1973-10-02
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Expires: 1991-04-13
Abstract
Abstract An extruder for thermoplastic material has a screw of a compression relief design for advancing and working the thermoplastic material to produce an extrudate at a more uniform temperature and with a more thorough mixing of thermoplastic materials than has been achieved in the past. A metering section of the screw is provided with pins for homogenizing the thermoplastic material with all of the pins in any one portion of the screw being arranged in a plane perpendicular to the axis of rotation of the extruder screw and directed radially outward from the axis of rotation. A helical flight formed on the extruder screw is uninterrupted in at least the metering portion of the screw.
Inventors
- 👤 R Deboo
- 👤 C Heard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 09:56
CPC Classifications
B; B29; B29C; B29C48/00; B29C48/25; B29C48/36; B29C48/50; B29C48/505; B29C48/565; B29C48/03
Claims Analysis
Total Claims: 57
Claim 1
Independent Claim
153 words
A method of advancing and working thermoplastic materials, which includes the steps of: revolving at least one channel about an axis of revolution to advance at least one thermoplastic material through the channel along a predetermined path; and subjecting the material to at least one plurality of forces exerted by force-producing components extending into the path and along axes which intersect the channel: all of the force-producing components in any one portion of the channel having at least some portion of the axis of each of the components in the portion lying in a plane which is perpendicular to the axis of revolution; any portion of the channel extending between the walls of the channel and a predetermined distance along the axis of revolution; the walls of the channel being formed by continuous surfaces intersecting with the plane so that the walls of the channel are uninterrupted at the intersection with the plane.
Claim 2
Independent Claim
153 words
A method of advancing and working thermoplastic materials, which includes the steps of: revolving at least one channel about an axis of revolution to advance at least one thermoplastic material through the channel along a predetermined path; and subjecting the material to at least one plurality of forces exerted by force-producing components extending into the path and along axes which intersect the channel: all of the force-producing components in any one portion of the channel having at least some portion of the axis of each of the components in the portion lying in a plane which is perpendicular to the axis of revolution; any portion of the channel extending between the walls of the channel and a predetermined distance along the axis of revolution; the walls of the channel being formed by continuous surfaces intersecting with the plane so that the walls of the channel are uninterrupted at the intersection with the plane.
Claim 3
Dependent Claim
20 words
The method of claim 1, wherein the channel is formed by a helical flight generated about the axis of revolution.
Claim 4
Dependent Claim
25 words
The method of claim 1, wherein the axes of all the force-producing elements in any one portion of the channel lie substantially in the plane.
Claim 5
Independent Claim
141 words
A method of advancing and working thermoplastic materials, which includes the steps of: revolving at least one channel about an axis of revolution to advance at least one thermoplastic material through the channel along a predetermined path; the walls of the channel being formed by turns of a flight formed about and along the axis of revolution; and subjecting the material to at least one plurality of forces exerted by force-producing components extending into the path; all of the force-producing components in the channel in any one turn of the flight having at least some portion of each of the components in the turn lying in a plane which is perpendicular to the axis of revolution; the walls of the channel being formed by continuous surfaces, intersecting the plane so that the channel is uninterrupted at the intersection with the plane.
Claim 6
Independent Claim
141 words
A method of advancing and working thermoplastic materials, which includes the steps of: revolving at least one channel about an axis of revolution to advance at least one thermoplastic material through the channel along a predetermined path; the walls of the channel being formed by turns of a flight formed about and along the axis of revolution; and subjecting the material to at least one plurality of forces exerted by force-producing components extending into the path; all of the force-producing components in the channel in any one turn of the flight having at least some portion of each of the components in the turn lying in a plane which is perpendicular to the axis of revolution; the walls of the channel being formed by continuous surfaces, intersecting the plane so that the channel is uninterrupted at the intersection with the plane.
Claim 7
Independent Claim
126 words
A method of advancing and working thermoplastic materials, which includes the steps of: rotating an extruder screw having at least one helical flight formed thereon about an axis of rotation to advance at least one thermoplastic material through a channel having walls formed by the flight; and subjecting the material to at least one plurality of forces exerted by force-producing components extending into the channel and along axes which intersect the channel; all the force-producing components in the channel in any one turn of the flight having at least some portion of the axis of each of the components in the turn lying in a plane which is perpendicular to the axis rotation; the at least one flight intersecting with the plane and being continuous therethrough.
Claim 8
Independent Claim
126 words
A method of advancing and working thermoplastic materials, which includes the steps of: rotating an extruder screw having at least one helical flight formed thereon about an axis of rotation to advance at least one thermoplastic material through a channel having walls formed by the flight; and subjecting the material to at least one plurality of forces exerted by force-producing components extending into the channel and along axes which intersect the channel; all the force-producing components in the channel in any one turn of the flight having at least some portion of the axis of each of the components in the turn lying in a plane which is perpendicular to the axis rotation; the at least one flight intersecting with the plane and being continuous therethrough.
Claim 9
Dependent Claim
30 words
The method of claim 5, wherein at least some portion of each one of all of the force-producing components in any one turn of the flight lies in the plane.
Claim 10
Dependent Claim
23 words
The method of claim 6, wherein all of the force-producing components in any one turn of the flight lie substantially in the plane.
Claim 11
Independent Claim
127 words
A method of advancing and working thermoplastic materials, which comprises the steps of: advancing at least one thermoplastic material through a helical channel extending along and about an axis of revolution; compressing the material; relieving the pressure in the material; and Homogenizing the material by subjecting the material to at least one plurality of forces subsequent to relieving the pressure in the material, the forces being exerted by force-producing components, all the force-producing components in the channel in any one turn thereof lying substantially in a plane which is perpendicular to the axis of revolution and directed radially outward from the axis of revolution; the helical channel having uninterrupted side boundaries at least along that portion of the predetermined path at which the force-producing components are positioned.
Claim 12
Independent Claim
127 words
A method of advancing and working thermoplastic materials, which comprises the steps of: advancing at least one thermoplastic material through a helical channel extending along and about an axis of revolution; compressing the material; relieving the pressure in the material; and Homogenizing the material by subjecting the material to at least one plurality of forces subsequent to relieving the pressure in the material, the forces being exerted by force-producing components, all the force-producing components in the channel in any one turn thereof lying substantially in a plane which is perpendicular to the axis of revolution and directed radially outward from the axis of revolution; the helical channel having uninterrupted side boundaries at least along that portion of the predetermined path at which the force-producing components are positioned.
Claim 13
Independent Claim
117 words
A method of advancing and working thermoplastic materials, which comprises the steps of: moving a core having at least one helical flight formed therealong rotatably about an axis of rotation to advance a thermoplastic material along a predetermined path; compressing the material; relieving the pressure in the material; and subjecting the material to at least one plurality of forces subsequent to relieving the pressure in the material, the forces being exerted by force-producing components; all of the force-producing components along the core in any one turn of the flight having at least some portion thereof lying in a plane which is perpendicular to the axis of rotation; the flight intersecting with and being continuous through the plane.
Claim 14
Independent Claim
117 words
A method of advancing and working thermoplastic materials, which comprises the steps of: moving a core having at least one helical flight formed therealong rotatably about an axis of rotation to advance a thermoplastic material along a predetermined path; compressing the material; relieving the pressure in the material; and subjecting the material to at least one plurality of forces subsequent to relieving the pressure in the material, the forces being exerted by force-producing components; all of the force-producing components along the core in any one turn of the flight having at least some portion thereof lying in a plane which is perpendicular to the axis of rotation; the flight intersecting with and being continuous through the plane.
Claim 15
Dependent Claim
24 words
The method of claim 9, wherein each one of the force-producing components in any one turn of the flight lies substantially in the plane.
Claim 16
Dependent Claim
17 words
The method of claim 10, wherein force-producing components are directed radially outward from the axis of rotation.
Claim 17
Independent Claim
237 words
A method of advancing and working thermoplastic materials, which comprises the steps of: introducing at least one thermoplastic material into engagement with a first zone of a screw mounted rotatably in a housing, the screw having a helical flight formed thereon; moving the screw rotatably about an axis of rotation to feed the thermoplastic materials longitudinally along the screw through a channel formed on the screw to a second zone of the screw; compressing the thermoplastic material in the second zone of the screw while the material is advanced simultaneously through the second zone to a third zone; relieving the pressure in the thermoplastic material in a third zone of the screw while the material is advanced through the third zone to a fourth zone; and advancing the thermoplastic material through a fourth metering zone of the screw while simultaneously homogenizing the material by subjecting the material to at least one group of a plurality of forces exerted by force-producing components spaced about the surface of the screw and extending into the channel, all of the force-producing components creating the forces being in a metering zone of the screw and all of the force-producing components along the metering zone of the screw in any one turn of the flight lying in a plane perpendicular of the axis of rotation of the screw, being directed radially outward from the axis of rotation, and being non-intersecting with the flight.
Claim 18
Independent Claim
237 words
A method of advancing and working thermoplastic materials, which comprises the steps of: introducing at least one thermoplastic material into engagement with a first zone of a screw mounted rotatably in a housing, the screw having a helical flight formed thereon; moving the screw rotatably about an axis of rotation to feed the thermoplastic materials longitudinally along the screw through a channel formed on the screw to a second zone of the screw; compressing the thermoplastic material in the second zone of the screw while the material is advanced simultaneously through the second zone to a third zone; relieving the pressure in the thermoplastic material in a third zone of the screw while the material is advanced through the third zone to a fourth zone; and advancing the thermoplastic material through a fourth metering zone of the screw while simultaneously homogenizing the material by subjecting the material to at least one group of a plurality of forces exerted by force-producing components spaced about the surface of the screw and extending into the channel, all of the force-producing components creating the forces being in a metering zone of the screw and all of the force-producing components along the metering zone of the screw in any one turn of the flight lying in a plane perpendicular of the axis of rotation of the screw, being directed radially outward from the axis of rotation, and being non-intersecting with the flight.
Claim 19
Independent Claim
160 words
An apparatus for advancing and working thermoplastic materials, which comprises: at least one channel having a base and side walls, the channel being generated about an axis of revolution; means for revolving the at least one channel about the axis of revolution to advance at least one thermoplastic material through the channel along a predetermined path; and at least one plurality of force-producing components extending into the path and along axes which intersect the base of the channel for subjecting the material to at least one plurality of forces; all of the force-producing components in the channel in any one turn thereof having at least some portion of the axis of each of the components in the section lying in a plane which is perpendicular to the axis of revolution; the walls of the channel being formed by surfaces intersecting with the plane so that the channel wallS are uninterrupted at the intersection with and are continuous through the plane.
Claim 20
Independent Claim
160 words
An apparatus for advancing and working thermoplastic materials, which comprises: at least one channel having a base and side walls, the channel being generated about an axis of revolution; means for revolving the at least one channel about the axis of revolution to advance at least one thermoplastic material through the channel along a predetermined path; and at least one plurality of force-producing components extending into the path and along axes which intersect the base of the channel for subjecting the material to at least one plurality of forces; all of the force-producing components in the channel in any one turn thereof having at least some portion of the axis of each of the components in the section lying in a plane which is perpendicular to the axis of revolution; the walls of the channel being formed by surfaces intersecting with the plane so that the channel wallS are uninterrupted at the intersection with and are continuous through the plane.
Claim 21
Independent Claim
147 words
An apparatus for advancing and working thermoplastic materials, which comprises: at least one channel having a base and side walls, the channel being generated about an axis of revolution; means for revolving the at least one channel about the axis of revolution to advance at least one thermoplastic material through the channel along a predetermined path; and at least one plurality of force-producing components extending into the path for subjecting the material to at least one plurality of forces; all of the force-producing components in the channel in any one turn thereof having at least some portion of each of the components in the turn lying in a plane which is perpendicular to the axis of revolution; the walls of the channel being formed by surfaces intersecting with the plane so that the channel walls are uninterrupted at the intersection with and are continuous through the plane.
Claim 22
Independent Claim
147 words
An apparatus for advancing and working thermoplastic materials, which comprises: at least one channel having a base and side walls, the channel being generated about an axis of revolution; means for revolving the at least one channel about the axis of revolution to advance at least one thermoplastic material through the channel along a predetermined path; and at least one plurality of force-producing components extending into the path for subjecting the material to at least one plurality of forces; all of the force-producing components in the channel in any one turn thereof having at least some portion of each of the components in the turn lying in a plane which is perpendicular to the axis of revolution; the walls of the channel being formed by surfaces intersecting with the plane so that the channel walls are uninterrupted at the intersection with and are continuous through the plane.
Claim 23
Dependent Claim
20 words
The apparatus of claim 14, wherein the channel is formed by a helical flight generated about the axis of revolution.
Claim 24
Dependent Claim
126 words
Apparatus for advancing and working thermoplastic materials, which comprises: a channel generated helically about an axis for advancing at least one thermoplastic material along a predetermined path; means for revolving the channel about the axis; and at least one plurality of force-producing components extending into the path along axes which intersect the channel and positioned along the axis of revolution for subjecting the material to a plurality of forces, all of the force-producing components in the channel in any one turn thereof having at least a portion of the axis thereof lying in a plane which is perpendicular to the axis of revolution; the walls of the channel being formed by surfaces, which surfaces intersect with the plane and which surfaces are continuous through the plane.
Claim 25
Dependent Claim
126 words
Apparatus for advancing and working thermoplastic materials, which comprises: a channel generated helically about an axis for advancing at least one thermoplastic material along a predetermined path; means for revolving the channel about the axis; and at least one plurality of force-producing components extending into the path along axes which intersect the channel and positioned along the axis of revolution for subjecting the material to a plurality of forces, all of the force-producing components in the channel in any one turn thereof having at least a portion of the axis thereof lying in a plane which is perpendicular to the axis of revolution; the walls of the channel being formed by surfaces, which surfaces intersect with the plane and which surfaces are continuous through the plane.
Claim 26
Dependent Claim
127 words
Apparatus for advancing and working thermoplastic materials, which comprises; a housing having a longitudinally extending bore formed therein and having a longitudinal axis; means disposed concentrically within the bore and having a flight formed helically thereon and extending substantially from one end thereof to the other for advancing a thermoplastic material from the one end to the other end thereof; means for rotating the advancing means about the longitudinal axis; and a plurality of means connected to the advancing means for homogenizing the thermoplastic material, all of the homogenizing means in any one turn of the flight being disposed substantially in one plane perpendicular to the longitudinal axis; the helical flight being continuous in at least the portion of the advancing means which contains the homogenizing means.
Claim 27
Dependent Claim
127 words
Apparatus for advancing and working thermoplastic materials, which comprises; a housing having a longitudinally extending bore formed therein and having a longitudinal axis; means disposed concentrically within the bore and having a flight formed helically thereon and extending substantially from one end thereof to the other for advancing a thermoplastic material from the one end to the other end thereof; means for rotating the advancing means about the longitudinal axis; and a plurality of means connected to the advancing means for homogenizing the thermoplastic material, all of the homogenizing means in any one turn of the flight being disposed substantially in one plane perpendicular to the longitudinal axis; the helical flight being continuous in at least the portion of the advancing means which contains the homogenizing means.
Claim 28
Dependent Claim
128 words
Apparatus for advancing and working thermoplastic materials, which comprises: means including at least one channel for advancing at least one thermoplastic material along a predetermined path through the channel extending along the predetermined path; and means for revolving the channel around an axis of revolution; and a plurality of means in the advancing means and directed radially outward from the axis of revolution for homogenizing the material; all the means in any one turn of the channel lying substantially in a plane which is perpendicular to the axis of revolution; the walls of the channel being formed by surfaces, which surfaces intersect with the plane and are continuous therethrough so as to have uninterrupted boundaries at least along that portion of the predetermined path containing the homogenizing means.
Claim 29
Dependent Claim
128 words
Apparatus for advancing and working thermoplastic materials, which comprises: means including at least one channel for advancing at least one thermoplastic material along a predetermined path through the channel extending along the predetermined path; and means for revolving the channel around an axis of revolution; and a plurality of means in the advancing means and directed radially outward from the axis of revolution for homogenizing the material; all the means in any one turn of the channel lying substantially in a plane which is perpendicular to the axis of revolution; the walls of the channel being formed by surfaces, which surfaces intersect with the plane and are continuous therethrough so as to have uninterrupted boundaries at least along that portion of the predetermined path containing the homogenizing means.
Claim 30
Dependent Claim
192 words
Apparatus for advancing and working thermoplastic materials, which comprises: a housing having a longitudinally extending cylindrical bore formed therein, an extrusion screw fitting closely within the bore and having a channel extending substantially from one end to the other end thereof generated helically about an axis of rotatioN of the screw, one end of the screw being a receiving end and the other end being a delivery end, for advancing a thermoplastic material from the receiving end of the screw to the delivery end thereof and for homogenizing the material; the screw being formed successively from the receiving end to the delivery end with a feed section, a compression section, a compression relief section, and a metering section, and a plurality of means in the channel for subjecting the thermoplastic materials to a plurality of forces; all the means in any one turn of the channel having at least an integral portion thereof disposed in one plane which is perpendicular to the axis of rotation of the screw; the walls of the channel being formed by surfaces intersecting with the plane so that the surfaces are uninterrupted and continuous through the plane.
Claim 31
Dependent Claim
192 words
Apparatus for advancing and working thermoplastic materials, which comprises: a housing having a longitudinally extending cylindrical bore formed therein, an extrusion screw fitting closely within the bore and having a channel extending substantially from one end to the other end thereof generated helically about an axis of rotatioN of the screw, one end of the screw being a receiving end and the other end being a delivery end, for advancing a thermoplastic material from the receiving end of the screw to the delivery end thereof and for homogenizing the material; the screw being formed successively from the receiving end to the delivery end with a feed section, a compression section, a compression relief section, and a metering section, and a plurality of means in the channel for subjecting the thermoplastic materials to a plurality of forces; all the means in any one turn of the channel having at least an integral portion thereof disposed in one plane which is perpendicular to the axis of rotation of the screw; the walls of the channel being formed by surfaces intersecting with the plane so that the surfaces are uninterrupted and continuous through the plane.
Claim 32
Dependent Claim
18 words
The apparatus of claim 19, wherein the subjecting means is disposed within the metering section of the screw.
Claim 33
Dependent Claim
51 words
The apparatus of claim 19, wherein the subjecting means includes at least one group of a plurality of force-producing components with all of the force-producing components in any one turn of the channel having at least a portion of each of the force-producing components in that turn lying in the plane.
Claim 34
Dependent Claim
40 words
The apparatus of claim 21, wherein all the force-producing components are positioned along the metering section of the screw, all of the force-producing components in any one turn of the metering section of the screw lying substantially in the plane.
Claim 35
Dependent Claim
32 words
The apparatus of claim 22, wherein the upstream one of the at least one group of components is spaced less than one turn downstream of the compression relief section of the screw.
Claim 36
Dependent Claim
21 words
The apparatus of claim 23, wherein a second group of force-producing components are positioned at the downstream end of the screw.
Claim 37
Dependent Claim
44 words
The apparatus of claim 24, wherein at least four groups of the force-producing components are spaced along the metering section of the screw, the middle two groups of components being equally spaced along the metering section between the upstream-most group and the downstream-most group.
Claim 38
Dependent Claim
51 words
The apparatus of claim 19, wherein the subjecting means includes one group of a plurality of pins arranged about the circumference of the screw, all of the pins in the at least one group lying substantially in the plane all of the pins being within the metering section of the screw.
Claim 39
Dependent Claim
20 words
The apparatus of claim 26, wherein the pins are directed radially perpendicularly of the axis of rotation of the screw.
Claim 40
Dependent Claim
33 words
The apparatus of claim 27, wherein the upstream one of the planes is spaced one-half the pitch of the screw downstream of the downstream end of the compression relief section of the screw.
Claim 41
Dependent Claim
156 words
A screw for advancing and working thermoplastic materials, which comprises: a core having an axis of rotation for advancing a thermoplastic material; at least one flight connected to and extending outwardly from the core to a surface of revolution concentric with the axis of rotation of the core, the flight being generated helically about the axis of rotation; and at least one plurality of force-producing components connected to the core for subjecting the material to a plurality of forces, the force-producing components extending beyond the core along axes which intersect the core and spaced from the surface of revolution, all of the force-producing components along the core in any one turn of the flight having at least some portion of the axis of each of the components in the turn of the flight lying in a plane which plane is perpendicular to the axis of rotation; the flight intersecting with and being continuous through the plane.
Claim 42
Dependent Claim
156 words
A screw for advancing and working thermoplastic materials, which comprises: a core having an axis of rotation for advancing a thermoplastic material; at least one flight connected to and extending outwardly from the core to a surface of revolution concentric with the axis of rotation of the core, the flight being generated helically about the axis of rotation; and at least one plurality of force-producing components connected to the core for subjecting the material to a plurality of forces, the force-producing components extending beyond the core along axes which intersect the core and spaced from the surface of revolution, all of the force-producing components along the core in any one turn of the flight having at least some portion of the axis of each of the components in the turn of the flight lying in a plane which plane is perpendicular to the axis of rotation; the flight intersecting with and being continuous through the plane.
Claim 43
Dependent Claim
147 words
A screw for advancing and working thermoplastic materials, which comprises: a core having an axis of rotation for advancing a thermoplastic material; at least one flight connected to and extending outwardly from the core to a surface of revolution concentric with the axis of rOtation of the core, the flight being generated helically about the axis of rotation; and at least one plurality of force-producing components connected to the core for subjecting the material to a plurality of forces, the force-producing components extending beyond the core and spaced from the surface of revolution, all of the force-producing components along the core in any one turn of the flight having at least some portion of each of the components in the turn of the flight lying in a plane which plane is perpendicular to the axis of rotation; the flight intersecting with and being continuous through the plane.
Claim 44
Dependent Claim
147 words
A screw for advancing and working thermoplastic materials, which comprises: a core having an axis of rotation for advancing a thermoplastic material; at least one flight connected to and extending outwardly from the core to a surface of revolution concentric with the axis of rOtation of the core, the flight being generated helically about the axis of rotation; and at least one plurality of force-producing components connected to the core for subjecting the material to a plurality of forces, the force-producing components extending beyond the core and spaced from the surface of revolution, all of the force-producing components along the core in any one turn of the flight having at least some portion of each of the components in the turn of the flight lying in a plane which plane is perpendicular to the axis of rotation; the flight intersecting with and being continuous through the plane.
Claim 45
Dependent Claim
135 words
A screw for advancing and working thermoplastic materials, which comprises: a core having an axis of rotation; at least one helical flight extending outwardly from the core to a surface of revolution concentric with the axis of rotation of the core, the at least one flight defining a channel measured in a transverse direction between adjacent turns of the flight, and extending in a helical path lengthwise of the core; and a plurality of means for subjecting a thermoplastic material to a plurality of forces to homogenize the material; all the means in any one turn of the flight disposed substantially in one plane which is perpendicular to the axis of rotation of the core; the helical flight being continuous at least in that portion of the screw in which the subjecting means is positioned.
Claim 46
Dependent Claim
135 words
A screw for advancing and working thermoplastic materials, which comprises: a core having an axis of rotation; at least one helical flight extending outwardly from the core to a surface of revolution concentric with the axis of rotation of the core, the at least one flight defining a channel measured in a transverse direction between adjacent turns of the flight, and extending in a helical path lengthwise of the core; and a plurality of means for subjecting a thermoplastic material to a plurality of forces to homogenize the material; all the means in any one turn of the flight disposed substantially in one plane which is perpendicular to the axis of rotation of the core; the helical flight being continuous at least in that portion of the screw in which the subjecting means is positioned.
Claim 47
Dependent Claim
41 words
The screw for advancing and working thermoplastic materials as set forth in claim 31, wherein: the core is formed with at least a metering section, and the subjecting means is disposed in at least one plane positioned along the metering section.
Claim 48
Dependent Claim
154 words
An extruder screw for advancing and working thermoplastic materials, which comprises: a core having an axis of rotation; a helical flight extending outwardly from the core to a surface of revolution concentric with the axis of rotation of the core, the flight defining a channel measured in a transverse direction between adjacent turns of the flight and extending in a longitudinal direction in a helical path lengthwise of the screw; the screw being formed with at least a feed section, a compression section, a compression relief section and a metering section, and at least one plurality of pins extending radially outwardly from the core towards the surface of revolution, all of the pins in any one turn of the flight being arranged substantially in a plane, the plane being perpendicular to the axis of rotation of the core, the helical flight being continuous in at least that section of the screw containing the pins.
Claim 49
Dependent Claim
154 words
An extruder screw for advancing and working thermoplastic materials, which comprises: a core having an axis of rotation; a helical flight extending outwardly from the core to a surface of revolution concentric with the axis of rotation of the core, the flight defining a channel measured in a transverse direction between adjacent turns of the flight and extending in a longitudinal direction in a helical path lengthwise of the screw; the screw being formed with at least a feed section, a compression section, a compression relief section and a metering section, and at least one plurality of pins extending radially outwardly from the core towards the surface of revolution, all of the pins in any one turn of the flight being arranged substantially in a plane, the plane being perpendicular to the axis of rotation of the core, the helical flight being continuous in at least that section of the screw containing the pins.
Claim 50
Dependent Claim
18 words
The extruder screw of claim 33, wherein the pins are located in the metering section of the screw.
Claim 51
Dependent Claim
25 words
The extruder screw of claim 34, wherein the plane in which the pins are disposed is located one-half turn downstream of the compression relief section.
Claim 52
Dependent Claim
53 words
The extruder screw of claim 34, wherein the pins are arranged in four planes spaced evenly along the metering section of the screw, the first one of the planes being one-half turn downstream of the compression relief section and the downstream one of the planes being at the downstream end of the screw.
Claim 53
Dependent Claim
19 words
The extruder screw of claim 34, wherein the height of the pins is less than that of the flight.
Claim 54
Dependent Claim
20 words
The extruder screw of claim 34, wherein the height of the pins is the same as that of the flight.
Claim 55
Dependent Claim
23 words
The screw of claim 34, wherein the upstream one of the planes is positioned approximately three-sixteenths inch downstream of the compression relief section.
Claim 56
Dependent Claim
33 words
The screw of claim 34, wherein the pins are three-sixteenths inch in diameter and the axes of the pins are spaced at least one-quarter inch apart along an axis circumferentially of the core.
Claim 57
Dependent Claim
40 words
The screw of claim 34, wherein the ratio of the area of the root surface between projections to the area of the outwardly exposed surfaces of the pins in any one portion of the core is between 0 and 1.
References Cited (Backward Citations)
US2581031A
Cited
US2802238A
Cited
US2838794A
Cited
US3115674A
Cited
US3115675A
Cited
US3160916A
Cited
US3497582A
Cited
US3486193A
Cited
US3487503A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-10-01 | 1977-04-02 | 1977-10-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-10-01 | 1981-04-02 | 1981-10-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-10-01 | 1985-04-02 | 1985-10-02 | $7700.00 | Window Closed / Lapsed |