US3694529A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for molding articles
Assignee: Honeywell International Inc
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Filing: 1970-04-02
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Granted: 1972-09-26
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Expires: 1990-04-02
Abstract
Abstract This disclosure is directed to a method for injection molding. Shot capacity of injection molding machines is increased by providing a low pressure accumulator which can receive a first charge of prepared molding material from a preparation chamber so as to store the first charge during the preparation of a second charge in the preparation chamber. Upon the completion of the preparation of the second charge, both the first charge from the accumulator and the second charge from the preparation chamber are injected into a mold cavity. Molding with foamable molding material is improved by communicating the accumulator with the mold cavity so as to allow expansion of the foamable molding material into the accumulator from the mold cavity during foaming. Material so received within the accumulator is thereafter recompressed for use as all or part of the first charge for the next subsequent molding cycle.
Inventors
- 👤 Roy C Josephsen
- 👤 Clifford L Weir
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 09:51
CPC Classifications
B; B29; B29C; B29C44/00; B29C44/34; B29C44/36; B29C44/38; B29C44/42; B29C44/421; B29C44/424; B29C45/00; B29C45/17; B29C45/46; B29C45/53; B29C45/54; B29C2045/548; B29C45/542; Y; Y10; Y10S; Y10S264/00; Y10S264/14; Y10S264/83
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
157 words
The method of injection molding a molding material to form an article including the steps of: melting a first charge of molding material in a chamber so as to prepare the charge for injection into a mold having a mold cavity; injecting said first charge of molding material from said chamber through a passage into an accumulator; maintaining said first charge of molding material within said accumulator while concurrently melting a second charge of molding material in said chamber so as to prepare the charge for injection into a mold having a mold cavity; injecting said first charge of molding material from said accumulator into said mold cavity; injecting said second charge of molding material from said chamber into said mold cavity; retaining said first and second charges of molding material within said mold cavity while allowing said material to set to take on the shape of said article; and removing said article from said mold cavity.
Claim 2
Independent Claim
157 words
The method of injection molding a molding material to form an article including the steps of: melting a first charge of molding material in a chamber so as to prepare the charge for injection into a mold having a mold cavity; injecting said first charge of molding material from said chamber through a passage into an accumulator; maintaining said first charge of molding material within said accumulator while concurrently melting a second charge of molding material in said chamber so as to prepare the charge for injection into a mold having a mold cavity; injecting said first charge of molding material from said accumulator into said mold cavity; injecting said second charge of molding material from said chamber into said mold cavity; retaining said first and second charges of molding material within said mold cavity while allowing said material to set to take on the shape of said article; and removing said article from said mold cavity.
Claim 3
Dependent Claim
36 words
The method of injection molding according to claim 1 wherein said step of injecting said first charge of molding material into said mold cavity comprises: advancing piston means against said molding material contained in said accumulator.
Claim 4
Independent Claim
228 words
The method of injection molding a foamable molding material including the steps of: melting a first charge of foamable molding material in a chamber so as to prepare the charge for injection into a mold having a mold cavity; injecting said first charge of foamable molding material from said chamber into an accumulator at a pressure sufficiently high to prevent foaming; maintaining said first charge of foamable molding material in said accumulator at a pressure sufficiently high to prevent foaming; melting a second charge of foamable molding material in said chamber so as to prepare the charge for injection into a mold having a mold cavity; injecting said first charge of foamable molding material from said accumulator into said mold cavity at a pressure sufficiently high to prevent foaming; injecting said second charge of foamable molding material from said chamber into said mold cavity at a pressure sufficiently high to prevent foaming; allowing said first and second charges of foamable molding material under pressure to set in said mold cavity so as to take on the shape of said mold cavity and form a solid skin around the inner surface of said mold cavity; and relieving the pressure from said foamable molding material so as to allow the foaming thereof within said solid skin and the expulsion of excess material out of said mold cavity into said accumulator.
Claim 5
Independent Claim
228 words
The method of injection molding a foamable molding material including the steps of: melting a first charge of foamable molding material in a chamber so as to prepare the charge for injection into a mold having a mold cavity; injecting said first charge of foamable molding material from said chamber into an accumulator at a pressure sufficiently high to prevent foaming; maintaining said first charge of foamable molding material in said accumulator at a pressure sufficiently high to prevent foaming; melting a second charge of foamable molding material in said chamber so as to prepare the charge for injection into a mold having a mold cavity; injecting said first charge of foamable molding material from said accumulator into said mold cavity at a pressure sufficiently high to prevent foaming; injecting said second charge of foamable molding material from said chamber into said mold cavity at a pressure sufficiently high to prevent foaming; allowing said first and second charges of foamable molding material under pressure to set in said mold cavity so as to take on the shape of said mold cavity and form a solid skin around the inner surface of said mold cavity; and relieving the pressure from said foamable molding material so as to allow the foaming thereof within said solid skin and the expulsion of excess material out of said mold cavity into said accumulator.
Claim 6
Dependent Claim
34 words
A method of injection molding as claimed in claim 3 and further including the step of: recompressing said excess material within said accumulator for use as a charge for the next subsequent molding cycle.
Claim 7
Dependent Claim
50 words
A method of injection molding according to claim 3 wherein said step of maintaining said first charge of foamable molding material in said accumulator at a pressure sufficiently high to prevent foaming includes: advancing a piston means mounted in said accumulator against the foamable molding material of said first charge.
Claim 8
Dependent Claim
89 words
A method of injection molding according to claim 3 wherein said accumulator has a piston mounted therein, wherein said step of maintaining said first charge of foamable molding material at a pressure sufficiently high to prevent foaming comprises exerting a force against said first charge of molding material through said piston; and wherein said step of injecting said first charge of foamabLe molding material comprises advancing said piston against said first charge of foamable molding material to displace said first charge from said accumulator and into said mold cavity.
Claim 9
Dependent Claim
29 words
A method of injection molding as claimed in claim 6 wherein said step of relieving the pressure for said foamable molding material comprises retracting said piston within said accumulator.
Claim 10
Independent Claim
467 words
A method of injection molding at least two articles from a foamable molding material including the steps of: melting a first charge of foamable molding material in a chamber so as to prepare the charge for injection into a mold having a mold cavity; injecting said first charge of foamable molding material from said chamber through a passage into an accumulator at a pressure sufficiently high to prevent foaming; maintaining said first charge of foamable molding material in said accumulator at a pressure sufficiently high to prevent foaming; melting a second charge of foamable molding material in said chamber so as to prepare the charge for injection into a mold having a mold cavity; injecting said first charge of foamable molding material from said accumulator into said cavity at a pressure sufficiently high to prevent foaming; injection said second charge of foamable molding material from said chamber into said mold cavity at a pressure sufficiently high to prevent foaming; allowing said first and second charges of foamable molding material under pressure to set in said mold cavity so as to take on the shape of said mold cavity and form a solid skin around the inner surface of said mold cavity to form one article; relieving the pressure from said foamable molding material so as to allow the foaming thereof within said solid skin and the expulsion of excess material out of said mold cavity into said accumulator; allowing said foamed molding material within said solid skin to set; removing said one article from said mold cavity; recompressing said excess molding material within said accumulator to form a first charge of molding material for a next subsequent molding cycle; melting a further charge of foamable molding material in said chamber so as to define a second charge for injection into said mold cavity during said next subsequent molding cycle; injecting said first charge of foamable molding material from said accumulator into said mold cavity at a pressure sufficiently high to prevent foaming; injecting said second charge of foamable molding material from said chamber into said mold cavity at a pressure sufficiently high to prevent foaming; allowing said first and second charges of foamable molding material under pressure to set in said mold cavity so as to take on the shape of said mold cavity and form a solid skin around the inner surface of said mold cavity to form a second article; relieving the pressure from said foamable molding material so as to allow the foaming thereof within said solid skin and the expulsion of excess material out of said mold cavity into said accumulator for use as the first charge in a next subsequent molding cycle; allowing said foamed molding material within said solid skin to set; and removing said second article from said mold cavity.
Claim 11
Independent Claim
467 words
A method of injection molding at least two articles from a foamable molding material including the steps of: melting a first charge of foamable molding material in a chamber so as to prepare the charge for injection into a mold having a mold cavity; injecting said first charge of foamable molding material from said chamber through a passage into an accumulator at a pressure sufficiently high to prevent foaming; maintaining said first charge of foamable molding material in said accumulator at a pressure sufficiently high to prevent foaming; melting a second charge of foamable molding material in said chamber so as to prepare the charge for injection into a mold having a mold cavity; injecting said first charge of foamable molding material from said accumulator into said cavity at a pressure sufficiently high to prevent foaming; injection said second charge of foamable molding material from said chamber into said mold cavity at a pressure sufficiently high to prevent foaming; allowing said first and second charges of foamable molding material under pressure to set in said mold cavity so as to take on the shape of said mold cavity and form a solid skin around the inner surface of said mold cavity to form one article; relieving the pressure from said foamable molding material so as to allow the foaming thereof within said solid skin and the expulsion of excess material out of said mold cavity into said accumulator; allowing said foamed molding material within said solid skin to set; removing said one article from said mold cavity; recompressing said excess molding material within said accumulator to form a first charge of molding material for a next subsequent molding cycle; melting a further charge of foamable molding material in said chamber so as to define a second charge for injection into said mold cavity during said next subsequent molding cycle; injecting said first charge of foamable molding material from said accumulator into said mold cavity at a pressure sufficiently high to prevent foaming; injecting said second charge of foamable molding material from said chamber into said mold cavity at a pressure sufficiently high to prevent foaming; allowing said first and second charges of foamable molding material under pressure to set in said mold cavity so as to take on the shape of said mold cavity and form a solid skin around the inner surface of said mold cavity to form a second article; relieving the pressure from said foamable molding material so as to allow the foaming thereof within said solid skin and the expulsion of excess material out of said mold cavity into said accumulator for use as the first charge in a next subsequent molding cycle; allowing said foamed molding material within said solid skin to set; and removing said second article from said mold cavity.
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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) | 1975-09-26 | 1976-03-27 | 1976-09-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-09-26 | 1980-03-27 | 1980-09-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-09-26 | 1984-03-27 | 1984-09-26 | $7700.00 | Window Closed / Lapsed |