US3758776A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for determining the melt index of plastics
Assignee: Scholven Chemie AG
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Filing: 1969-05-12
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Granted: 1973-09-11
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Expires: 1989-05-12
Abstract
Abstract In the determining of the melt index of plastics, a sample is forced from a cylinder through a calibrated orifice by means of a weighted plunger in a conventional manner. In this invention, the rate of movement of the plunger is converted to a series of electrical pulses which pulses are fed to a digital counter that determines the number of such pulses over a predetermined time interval. If the apparatus including the counter are suitably calibrated, the melt index of a sample can be displayed by the counter directly without the need to convert the reading.
Inventors
- 👤 W Schneider
- 👤 J Frohne
- 👤 E Hohmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:40
CPC Classifications
G; G01; G01N; G01N11/00; G01N11/02; G01N11/04; G01N11/06
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
152 words
Apparatus for directly measuring the melt index of a plastic comprising a cylindrical chamber adapted to be heated and to contain a charge of plastic, a calibrated orifice in one end of said chamber, a plunger mating with said chamber and adapted to expel said charge through said orifice with a predetermined force, means for converting the downward movement of said plunger into electrical impulses including means attaching said plunger to a rotatable disk adapted to cause said disk to rotate with a speed directly proportional to the linear speed of said plunger, said disk having spaced markings thereon, and impulse pick-up means adapted to observe said markings as the disk rotates, counting means having a digital readout adapted to receive said electrical impulses, said apparatus and said counting means being adapted to directly measure and display said melt index without measuring distance and time seParately and computing the melt index therefrom.
Claim 2
Dependent Claim
152 words
Apparatus for directly measuring the melt index of a plastic comprising a cylindrical chamber adapted to be heated and to contain a charge of plastic, a calibrated orifice in one end of said chamber, a plunger mating with said chamber and adapted to expel said charge through said orifice with a predetermined force, means for converting the downward movement of said plunger into electrical impulses including means attaching said plunger to a rotatable disk adapted to cause said disk to rotate with a speed directly proportional to the linear speed of said plunger, said disk having spaced markings thereon, and impulse pick-up means adapted to observe said markings as the disk rotates, counting means having a digital readout adapted to receive said electrical impulses, said apparatus and said counting means being adapted to directly measure and display said melt index without measuring distance and time seParately and computing the melt index therefrom.
Claim 3
Dependent Claim
25 words
The apparatus of claim 1 wherein said impulse pick-up means is a photoelectric cell and said markings are perforations about the periphery of said disk.
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) | 1976-09-10 | 1977-03-12 | 1977-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-10 | 1981-03-12 | 1981-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-10 | 1985-03-12 | 1985-09-11 | $7700.00 | Window Closed / Lapsed |