US3784065A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Injection
Assignee: Individual
•
Filing: 1971-07-12
•
Granted: 1974-01-08
•
Expires: 1991-07-12
Abstract
Abstract The invention provides a method of injecting by forcing, and apparatus for carrying out that method, which comprises the steps of (i) introducing material to be injected into a cylinder, (ii) compressing the solid material to injection pressure by rotating a screw in said cylinder, (iii) preventing said solid material at least to a large extent from slipping counter to the direction of rotation of the screw to achieve this pressure, (iv) plasticizing the solid material in a small space outside the zone where pressure is generated, and (v) injecting the plasticised material by forcing into a mould by means of the pressure generated in the solid material.
Inventors
- 👤 G Patfoort
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 00:55
CPC Classifications
B; B29; B29C; B29C45/00; B29C45/17; B29C45/46; B29C45/58; B29C45/62; B29C45/47; B29C45/60
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
149 words
Apparatus for injecting into a mold comprising, an elongated cylinder having an end wall provided with a relatively small opening therethrough, means for supplying granular thermoplastic material to the interior of the cylinder. a feed screw within the cylinder fixed against axial movement and rotatable for feeding the granular material axially toward said end wall, a terminal end of said screw being spaced from said end wall to provide a chamber, and means for supplying heat and confining it to the material within the chamber to render it viscous, whereby continued pressure of the solid material moved by the screw against the plasticized material in said spaced extrudes it through said opening in the end wall, wherein the means for confining the heat to the material within the chamber includes a thermal shield positioned at the terminal end of the screw for preventing heat flow thereto from the chamber.
Claim 2
Dependent Claim
149 words
Apparatus for injecting into a mold comprising, an elongated cylinder having an end wall provided with a relatively small opening therethrough, means for supplying granular thermoplastic material to the interior of the cylinder. a feed screw within the cylinder fixed against axial movement and rotatable for feeding the granular material axially toward said end wall, a terminal end of said screw being spaced from said end wall to provide a chamber, and means for supplying heat and confining it to the material within the chamber to render it viscous, whereby continued pressure of the solid material moved by the screw against the plasticized material in said spaced extrudes it through said opening in the end wall, wherein the means for confining the heat to the material within the chamber includes a thermal shield positioned at the terminal end of the screw for preventing heat flow thereto from the chamber.
Claim 3
Dependent Claim
44 words
Apparatus according to claim 1 including means to retain the material within a cylinder portion at the location of the feed and pressure zones in a solid state by maintaining said cylinder portion at a temperature below that at which the material becomes viscous.
Claim 4
Dependent Claim
27 words
Apparatus according to claim 1 in which a portion of the cylinder which surrounds the screw is grooved in order to prevent slipping of the granular material.
Claim 5
Dependent Claim
35 words
Apparatus according to claim 1 including means for varying the speed of rotation of the screw in order to vary the rate of flow of the viscous material through the opening in the end wall.
Claim 6
Dependent Claim
31 words
Apparatus according to claim 1 wherein the opening in the end wall is provided with an outlet nozzle provided with a valve therein for controlling flow of the viscous material therethrough.
Claim 7
Dependent Claim
141 words
Apparatus for injecting into a mold comprising, an elongated cylinder having an end wall provided with a relatively small opening therethrough, means for supplying granular themoplastic material to the interior of the cylinder, a feed screw within the cylinder fixed against axial movement and rotatable for feeding the granular material axially toward said end wall, a terminal end of said screw being spaced from said end wall to provide a chamber, and means for supplying heat and confining it to the material within the chamber to render it viscous, whereby continued pressure of the solid material moved by the screw against the plasticized material in said space extrudes it through said opening in the end wall, said cylinder including a portion thereof which surrounds the screw, mounted for rotation about its axis for controlling feed of the material by said screw.
Claim 8
Dependent Claim
141 words
Apparatus for injecting into a mold comprising, an elongated cylinder having an end wall provided with a relatively small opening therethrough, means for supplying granular themoplastic material to the interior of the cylinder, a feed screw within the cylinder fixed against axial movement and rotatable for feeding the granular material axially toward said end wall, a terminal end of said screw being spaced from said end wall to provide a chamber, and means for supplying heat and confining it to the material within the chamber to render it viscous, whereby continued pressure of the solid material moved by the screw against the plasticized material in said space extrudes it through said opening in the end wall, said cylinder including a portion thereof which surrounds the screw, mounted for rotation about its axis for controlling feed of the material by said screw.
Claim 9
Dependent Claim
11 words
Apparatus according to claim 6 including means for rotating the portion.
Claim 10
Dependent Claim
19 words
Apparatus in accordance with claim 7 including a brake member for controlling the speed of rotation of said portion.
Claim 11
Dependent Claim
148 words
Apparatus for injecting into a mold comprising, an elOngated cylinder having an end wall provided with a relatively small opening therethrough, means for supplying granular thermoplastic material to the interior of the cylinder, a feed screw within the cylinder fixed against axial movement and rotatable for feeding the granular material axially toward said end wall, a terminal end of said screw being spaced from said end wall to provide a chamber, and means for supplying heat and confining it to the material within the chamber to render it viscous, whereby continued pressure of the solid material moved by the screw against the plasticized material in said space extrudes it through said opening in the end wall, the means for supplying the granular material to the cylinder being adjustable along the length thereof to vary the length of the path along which the material is fed by the screw.
Claim 12
Dependent Claim
148 words
Apparatus for injecting into a mold comprising, an elOngated cylinder having an end wall provided with a relatively small opening therethrough, means for supplying granular thermoplastic material to the interior of the cylinder, a feed screw within the cylinder fixed against axial movement and rotatable for feeding the granular material axially toward said end wall, a terminal end of said screw being spaced from said end wall to provide a chamber, and means for supplying heat and confining it to the material within the chamber to render it viscous, whereby continued pressure of the solid material moved by the screw against the plasticized material in said space extrudes it through said opening in the end wall, the means for supplying the granular material to the cylinder being adjustable along the length thereof to vary the length of the path along which the material is fed by the screw.
Claim 13
Dependent Claim
135 words
Apparatus for injecting into a mold comprising, an elongated cylinder having an end wall provided with a relatively small opening therethrough, means for supplying granular thermoplastic material to the interior of the cylinder, a feed screw within the cylinder fixed against axial movement and rotatable for feeding the granular material axially toward said end wall, a terminal end of said screw being spaced from said end wall to provide a chamber, and means for supplying heat and confining it to the material within the chamber to render it viscous, whereby continued pressure of the solid material moved by the screw against the plasticized material in said space extrudes it through said opening in the end wall, a portion of the cylinder surrounding the screw being rotatable about its axis and provided with grooves internally thereof.
Claim 14
Dependent Claim
135 words
Apparatus for injecting into a mold comprising, an elongated cylinder having an end wall provided with a relatively small opening therethrough, means for supplying granular thermoplastic material to the interior of the cylinder, a feed screw within the cylinder fixed against axial movement and rotatable for feeding the granular material axially toward said end wall, a terminal end of said screw being spaced from said end wall to provide a chamber, and means for supplying heat and confining it to the material within the chamber to render it viscous, whereby continued pressure of the solid material moved by the screw against the plasticized material in said space extrudes it through said opening in the end wall, a portion of the cylinder surrounding the screw being rotatable about its axis and provided with grooves internally thereof.
Claim 15
Dependent Claim
20 words
Apparatus according to claim 10 wherein said portion is provided by radially movable sections in which the grooves are located.
Claim 16
Dependent Claim
19 words
Apparatus according to claim 11 including a motor for rotating the portion counter to the rotation of the screw.
Claim 17
Dependent Claim
19 words
Apparatus according to claim 12 wherein a brake is provided to control the speed of rotation of said portion.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-01-07 | 1977-07-09 | 1978-01-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-01-07 | 1981-07-09 | 1982-01-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-01-07 | 1985-07-09 | 1986-01-08 | $7700.00 | Window Closed / Lapsed |