US3890308A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Plastic injection molding machine
Assignee: Package Machinery Co
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Filing: 1973-10-12
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Granted: 1975-06-17
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Expires: 1993-10-12
Abstract
Abstract A plastic injection molding machine utilizing a gear driven toggle linkage for reciprocating a movable die plate relative to a fixed die plate to engage or close and to open the sections or halves of a mold. The linkage is characterized in that the toggle draws the movable plate toward the fixed plate and locks the mold halves in engaged position when the toggle is substantially ''''dead center'''' at its shortest length. The machine also features a reciprocating screw in its plasticizing and injecting unit, and a common drive is provided for the toggle linkage and the screw.
Inventors
- 👤 Harvey H Collins
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:53
CPC Classifications
B; B29; B29C; B29C45/00; B29C45/17; B29C45/64; B29C45/66; B29C45/70; Y; Y10; Y10T; Y10T74/00; Y10T74/20; Y10T74/20576; Y10T74/20582; Y10T74/20588
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
167 words
In a plastic injection molding machine having a longitudinally extending base, a plasticizing and injecting unit, and a fixed die plate mounted transversely on the base and supporting a mold half, a carriage movable longitudinally on the base and supporting a second die plate and complementary mold half, a mechanism for reciprocating the carriage and thereby to engage and disengage the mold halves, said mechanism comprising at least two toggles respectively disposed on opposite sides of a longitudinal plane through the mold halves, each such toggle including a crank arm and connecting arm which are respectively pivotally connected to the carriage and to the fixed die plate and also to each other, and a common drive for simultaneously pivoting the crank arms between positions wherein the mold halves are engaged and most widely separated, the first such position being when each toggle is substantially dead center and of shortest length and the second such position being when each toggle is substantially dead center and of greatest length.
Claim 2
Dependent Claim
167 words
In a plastic injection molding machine having a longitudinally extending base, a plasticizing and injecting unit, and a fixed die plate mounted transversely on the base and supporting a mold half, a carriage movable longitudinally on the base and supporting a second die plate and complementary mold half, a mechanism for reciprocating the carriage and thereby to engage and disengage the mold halves, said mechanism comprising at least two toggles respectively disposed on opposite sides of a longitudinal plane through the mold halves, each such toggle including a crank arm and connecting arm which are respectively pivotally connected to the carriage and to the fixed die plate and also to each other, and a common drive for simultaneously pivoting the crank arms between positions wherein the mold halves are engaged and most widely separated, the first such position being when each toggle is substantially dead center and of shortest length and the second such position being when each toggle is substantially dead center and of greatest length.
Claim 3
Dependent Claim
34 words
The mechanism defined in claim 1 wherein the said longitudinal plane is horizontal and each such toggle is so arranged that its crank and connecting arms are horizontally disposed when in dead center positions.
Claim 4
Dependent Claim
21 words
The mechanism of claim 2 wherein there are two toggles above the longitudinal plane and two toggles below the longitudinal plane.
Claim 5
Dependent Claim
59 words
The mechanism of claim 1 wherein the common drive for the toggles comprises a driven gear sector mounted on the carriage for oscillation, and a drive pinion associated with each crank arm, one of which crank arm pinions is directly engaged with the sector and the other of which is indirectly engaged with the sector through an idler pinion.
Claim 6
Dependent Claim
112 words
The mechanism as set forth in claim 3 wherein the common drive for the toggles comprises a driven rotatable crank, a lever pivotally connected to said last mentioned crank, a pair of gear sectors mounted on said carriage and connected to said lever for oscillation thereby, there being one such sector associated with each pair of toggles wherein a pair comprises a toggle above and a toggle below the longitudinal plane, a drive pinion associated with each crank arm in a toggle pair, one of which crank arm pinions is directly engaged with the associated sector and the other of whiCh is indirectly engaged with the associated sector through an idler pinion.
Claim 7
Dependent Claim
49 words
The injection molding machine of claim 1 wherein the said second die plate is supported on said carriage for adjustment toward and away from said first die plate to assure engagement of the mold halves with preselected force when the toggles are substantially dead center and of shortest length.
Claim 8
Dependent Claim
47 words
The machine as defined in claim 6 wherein a shaft is threaded into said carriage and rotatably received in and supports said second die plate for longitudinal movement relative to said carriage responsive to rotation of said shaft, and means is provided for rotation of said shaft.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-06-16 | 1978-12-16 | 1979-06-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-16 | 1982-12-16 | 1983-06-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-16 | 1986-12-16 | 1987-06-17 | $7700.00 | Window Closed / Lapsed |