US3604059A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pressure fill system
Assignee: Crown Molding Co
•
Filing: 1969-02-06
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Granted: 1971-09-14
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Expires: 1989-02-06
Abstract
Abstract A pressure fill system for a molding machine used for making plastic cups and the like. A pressure chamber in the material supply conduit is provided with a valve which is opened to feed into a filler cavity and closed while the chamber is pressurized and the material conveyed into the mold cavity.
Inventors
- 👤 Stephen Liddell
- 👤 Bill Matheson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:45
CPC Classifications
B; B29; B29C; B29C31/00; B29C31/04; B29C31/041; B29C31/02; B29C44/00; B29C44/34; B29C44/36; B29C44/38; B29C44/44; B29C44/445; Y; Y10; Y10S; Y10S264/00; Y10S264/10
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
153 words
In a machine for molding thin-walled cups from foamable polystyrene beads, a mold cavity defining a cup and constructed to be open and closed so that a cup may be molded therein and removed, a fill port communicating with the mold cavity at what will be the bottom of the cup, a movable plunger aligned with the fill port constructed to open and close it, source of pressure air at the fill port for blowing beads into the molding cavity, a pressure chamber connected to the fill port through which beads move to the fill port, an entrance valve at the entrance to the pressure chamber through which beads pass on their way to the pressure chamber from a source of bead supply, and a source of pressure air connected to the pressure chamber constructed to pressurize the chamber when the entrance valve is closed to thereby prevent reverse flow of the beads.
Claim 2
Dependent Claim
153 words
In a machine for molding thin-walled cups from foamable polystyrene beads, a mold cavity defining a cup and constructed to be open and closed so that a cup may be molded therein and removed, a fill port communicating with the mold cavity at what will be the bottom of the cup, a movable plunger aligned with the fill port constructed to open and close it, source of pressure air at the fill port for blowing beads into the molding cavity, a pressure chamber connected to the fill port through which beads move to the fill port, an entrance valve at the entrance to the pressure chamber through which beads pass on their way to the pressure chamber from a source of bead supply, and a source of pressure air connected to the pressure chamber constructed to pressurize the chamber when the entrance valve is closed to thereby prevent reverse flow of the beads.
Claim 3
Dependent Claim
30 words
The structure of claim 1 further characterized in that the source of pressure air at the fill port is in the form of an air passage through the movable plunger.
Claim 4
Dependent Claim
77 words
The structure of claim 1 further characterized in that the entrance valve is in the form of a rotatable ball valve. 4 The structure of claim 2 further characterized by and including means for operating the entrance valve, the movable plunger and the source of pressure air connected to the pressure chamber such that the entrance valve is closed first after which the plunger is raised to open the fill port and the pressure chamber is pressurized.
References Cited (Backward Citations)
US3179134A
Cited
US3375309A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-13 | 1975-03-15 | 1975-09-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-13 | 1979-03-15 | 1979-09-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-13 | 1983-03-15 | 1983-09-14 | $7700.00 | Window Closed / Lapsed |