Patent US3879720A successfully refreshed from Google Patents.
Patent US2759221A successfully refreshed from Google Patents.
US2759221A
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Injection (plastic) moulding machines
Assignee: Pierwood Plastics Ltd
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Filing: 1952-07-08
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Granted: 1956-08-21
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Expires: 1972-07-08
Abstract
No abstract record available.
Inventors
- 👤 Edwards Frederick Harold
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 03:29
CPC Classifications
B; B29; B29C; B29C45/00; B29C45/17; B29C45/76; B29C45/7626; B29C45/03; B29C45/40; B29C45/42
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
143 words
IN AN INJECTION MOULDING MACHINE OF THE TYPE HAVING A DIE AND MECHANISM TO CLOSE AND OPEN THE DIE AND HAVING MEANS TO INJECT PLASTIC MATERIAL INTO THE CLOSED DIE, THE PROVISION OF A BALANCE TRAP CONSISTING OF A PLATE PIVOTALLY MOUNTED IN THE MACHINE AND BALANCED BY A WEIGHT ADJUSTABLY POSITIONED THEREON, A DEVICE TO HOLD THE BALANCE TRAP IN TIPPING POSITION, WHEN MOVED TO SUCH POSITION BY AN ARTICLE DEPOSITED THEREON, MEANS ACTUATED BY DEVICES CONTROLLING THE CYCLE OF OPERATIONS OF THE MACHINE TO RAISE THE BALANCE TRAP TO RECEIVING POSITION, A SWITCH IN AN ELECTRIC CIRCUIT SUPPLYING POWER TO THE SAID DEVICES CONTROLLING THE CYCLE OF OPERATIONS OF THE MACHINE, SAID SWITCH BEING CONSTRUCTED AND ARRANGED TO BE OPENED BY THE RAISING OF THE BALANCE TRAP AND TO BE CLSOED BY SAID BALANCE TRAP WHEN IT FALLS, A SECOND SWITCH
Claim 2
Dependent Claim
143 words
IN AN INJECTION MOULDING MACHINE OF THE TYPE HAVING A DIE AND MECHANISM TO CLOSE AND OPEN THE DIE AND HAVING MEANS TO INJECT PLASTIC MATERIAL INTO THE CLOSED DIE, THE PROVISION OF A BALANCE TRAP CONSISTING OF A PLATE PIVOTALLY MOUNTED IN THE MACHINE AND BALANCED BY A WEIGHT ADJUSTABLY POSITIONED THEREON, A DEVICE TO HOLD THE BALANCE TRAP IN TIPPING POSITION, WHEN MOVED TO SUCH POSITION BY AN ARTICLE DEPOSITED THEREON, MEANS ACTUATED BY DEVICES CONTROLLING THE CYCLE OF OPERATIONS OF THE MACHINE TO RAISE THE BALANCE TRAP TO RECEIVING POSITION, A SWITCH IN AN ELECTRIC CIRCUIT SUPPLYING POWER TO THE SAID DEVICES CONTROLLING THE CYCLE OF OPERATIONS OF THE MACHINE, SAID SWITCH BEING CONSTRUCTED AND ARRANGED TO BE OPENED BY THE RAISING OF THE BALANCE TRAP AND TO BE CLSOED BY SAID BALANCE TRAP WHEN IT FALLS, A SECOND SWITCH
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) | 1959-08-21 | 1960-02-20 | 1960-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-08-21 | 1964-02-20 | 1964-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-08-21 | 1968-02-20 | 1968-08-21 | $7700.00 | Window Closed / Lapsed |