US3605871A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Die casting machine including sequentially acting compound pistion assembly machine
Assignee: Individual
•
Filing: 1969-05-01
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Granted: 1971-09-20
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Expires: 1989-05-01
Abstract
Abstract THE PISTON ASSEMBLY OF A DIE CASTING OR PLASTIC INJECTION MACHINE INCLUDES INNER AND OUTER CONCENTRIC PISTONS. THE INNER PISTON IS DIRECTLY DRIVE WHILE THE OUTER PISTON IS DRIVEN THROUGH THE MEDIUM OF A STACK OF CONICAL WASHERS SO THAT WHEN THE METAL OR PLASTIC BEING CAST ATTAINS A PREDETERMINED PRESSURE, THE WASHERS COLLAPSE AND ARREST MOTION OF THE OUTER PISTON WHILE THE INNER PISTON CONTINUES TO MOVE, GREATLY INCREASING THE INTERNAL PRESURE AT FINAL CHILLING.
Inventors
- 👤 Richard K Whitehead Sr
- 👤 Richard K Whitehead Jr
- 👤 Harry C Whitehead
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 13:41
CPC Classifications
B; B22; B22D; B22D17/00; B22D17/20; B22D17/2015; B22D17/203
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-19 | 1975-03-21 | 1975-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-19 | 1979-03-21 | 1979-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-19 | 1983-03-21 | 1983-09-20 | $7700.00 | Window Closed / Lapsed |