US4373886A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for injecting confluent streams of plastic material into an injection molding die
Assignee: Individual
•
Filing: 1981-06-17
•
Granted: 1983-02-15
•
Expires: 2001-06-17
Abstract
Abstract An apparatus for the production of marbled articles by injecting into the injection molding die of an injection molding machine two confluent streams of plastic raw material of different hue or color which are supplied from two injection units, via separate pulsation channels which open into a common nozzle channel, just ahead of the mold cavity. The plastic raw materials flowing in the two pulsation channels are subjected to an intermittant and alternatingly pulsating advance by means of feed thrust pulsation controls which generate an intermittant advance of the plastification screws of the injection units. At the junction between the two pulsation channels may be arranged a pulsation chamber with oppositely oriented material entry ports which are alternatingly closed by a reciprocating pulsating element which moves with the pulsating plastic streams.
Inventors
- 👤 Karl Hehl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 00:01
CPC Classifications
B; B29; B29C; B29C45/00; B29C45/17; B29C45/26; B29C45/27; B29C45/2725; B29C45/16; B29C45/1634
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
388 words
An apparatus for injecting confluent streams of plastic raw material from separate sources into the molding die of an injection molding machine, which machine has a die closing unit carrying a stationary die half on a stationary die carrier plate and a movable die half on a movable die carrier plate, guiding the latter for axial die opening and closing movements on at least two parallel tie rods, the plastic materials injecting apparatus comprising in combination: an injector head in the form of an intermediate stationary die plate which is mounted on the stationary die carrier plate and supports a stationary cavity plate, as part of the stationary die half; a generally axially oriented sprue opening in the stationary cavity plate; a generally axially oriented first injection unit with a plastification screw surrounded by a plastification cylinder having a cylinder nozzle at its discharge end and hydraulic drive means operable to rotate and axially advance the plastification screw for plastification and injection of a first raw material through said cylinder nozzle; an axial pulsation channel in the injector head linking the opening of the cylinder nozzle of the first injection unit with the sprue opening of the stationary cavity plate; a generally radially oriented second injection unit with a plastification screw surrounded by a plastification cylinder having a cylinder nozzle at its discharge end and hydraulic drive means operable to rotate and axially advance the plastification screw for plastification and injection of a second raw material through said cylinder nozzle; a radial pulsation channel linking the opening of the cylinder nozzle of the second injection unit with the sprue opening of the stationary cavity plate; a centrally located injector nozzle as part of the injector head, the injector nozzle having a cavity which forms a flow junction at an acute angle between the axial and radial pulsation channels and a common nozzle discharge channel at its discharge end, the latter leading directly into the sprue opening of the stationary cavity plate; a pair of supporting rods guiding the first injection unit for axial movements in relation to the injection head; and a pair of supporting rods similarly guiding the second injection unit for radial movements in relation to the injection head, both pairs of supporting rods being rigidly connected to the stationary structure of the die closing unit.
Claim 2
Independent Claim
388 words
An apparatus for injecting confluent streams of plastic raw material from separate sources into the molding die of an injection molding machine, which machine has a die closing unit carrying a stationary die half on a stationary die carrier plate and a movable die half on a movable die carrier plate, guiding the latter for axial die opening and closing movements on at least two parallel tie rods, the plastic materials injecting apparatus comprising in combination: an injector head in the form of an intermediate stationary die plate which is mounted on the stationary die carrier plate and supports a stationary cavity plate, as part of the stationary die half; a generally axially oriented sprue opening in the stationary cavity plate; a generally axially oriented first injection unit with a plastification screw surrounded by a plastification cylinder having a cylinder nozzle at its discharge end and hydraulic drive means operable to rotate and axially advance the plastification screw for plastification and injection of a first raw material through said cylinder nozzle; an axial pulsation channel in the injector head linking the opening of the cylinder nozzle of the first injection unit with the sprue opening of the stationary cavity plate; a generally radially oriented second injection unit with a plastification screw surrounded by a plastification cylinder having a cylinder nozzle at its discharge end and hydraulic drive means operable to rotate and axially advance the plastification screw for plastification and injection of a second raw material through said cylinder nozzle; a radial pulsation channel linking the opening of the cylinder nozzle of the second injection unit with the sprue opening of the stationary cavity plate; a centrally located injector nozzle as part of the injector head, the injector nozzle having a cavity which forms a flow junction at an acute angle between the axial and radial pulsation channels and a common nozzle discharge channel at its discharge end, the latter leading directly into the sprue opening of the stationary cavity plate; a pair of supporting rods guiding the first injection unit for axial movements in relation to the injection head; and a pair of supporting rods similarly guiding the second injection unit for radial movements in relation to the injection head, both pairs of supporting rods being rigidly connected to the stationary structure of the die closing unit.
Claim 3
Dependent Claim
75 words
A plastic materials injecting apparatus as defined in claim 1, wherein the injector nozzle protrudes axially from the injector head into a matching recess of the cavity plate of the stationary die half; and the injector nozzle has an end face at its discharge side which forms a part of the surface of the die cavity, so that the discharge opening of the nozzle discharge channel coincides with the sprue opening of the cavity plate.
Claim 4
Dependent Claim
49 words
A plastic materials injecting apparatus as defined in claim 1, further comprising means for heating the injector nozzle and the pulsation channels of the injector head; and insulating plates interposed between the injector head and the stationary die carrier plate and between the injector head and the cavity plate.
Claim 5
Dependent Claim
115 words
A plastic materials injecting apparatus as defined in any one of claims 1 through 3, wherein the injector nozzle has a cavity in the form of a pulsation chamber upstream of its nozzle discharge channel; the two pulsation channels open into the pulsation chamber through entry ports which are located opposite each other; and the injector nozzle further includes a pulsating element which is floatingly arranged inside the pulsation chamber, the pulsating element cooperating with the entry ports of the pulsation channels in such a way that an inflow of raw material from one entry port will move the pulsating element into a closing position in relation to the other entry port, and vice versa.
Claim 6
Dependent Claim
45 words
A plastic materials injecting apparatus as defined in any one of claims 1 through 3, further comprising means for mounting the second injection unit in relation to the stationary die carrier plate in such a way that its axial distance to said plate is adjustable.
Claim 7
Dependent Claim
49 words
A plastic materials injecting apparatus as defined in claim 5, wherein the mounting means for the second injection unit includes two mounting yokes which are attached to the proximate extremities of the supporting rods and adapted to be clamped to the two tie rods of the die closing unit.
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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) | 1986-02-14 | 1986-08-16 | 1987-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-14 | 1990-08-16 | 1991-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-14 | 1994-08-16 | 1995-02-15 | $7700.00 | Window Closed / Lapsed |