US4092089A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for the preparation of melt-sprayed spherical phenacetin granules
Assignee: Bayer AG
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Filing: 1977-05-19
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Granted: 1978-05-30
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Expires: 1997-05-19
Abstract
Abstract An apparatus for melt-spraying thermally sensitive material of low viscosity comprises a heatable multi-screw extruder having intermeshing, self-cleaning screws of specified clearance between the screws and between the screws and the extruder housing, a heatable pump for delivering molten material from the extruder to a heatable atomizer and a spray tank in which the atomizer is located for cooling and solidifying the melt-sprayed material.
Inventors
- 👤 Ernst Bocker
- 👤 Wolfgang Kracht
- 👤 Roland Rupp
- 👤 Erhard Schellmann
- 👤 Viktor Trescher
- 👤 Martin Ullrich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 21:59
CPC Classifications
A; A61; A61K; A61K9/00; A61K9/14; A61K9/16; A61K9/1682; A61K9/1688; A61K31/00; A61K31/16; A61K31/165; A61K9/20; A61K9/2095; B; B29; B29C; B29C48/00; B29C48/25; B29C48/36; B29C48/395; B29C48/40; B29C48/402; B29C48/03; B29C48/04; Y; Y10; Y10S; Y10S425/00; Y10S425/23
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
178 words
Apparatus for melt-spraying a material that is thermally sensitive in the molten state and has a melt viscosity of from about 0.5 to about 500 cp., which comprises (a) a multi-screw extruder for melting said material comprising intermeshing, self-cleaning screws having a clearance between the intermeshing screw shafts and a clearance between the screws and the housing of the extruder in the range of from about 4 × 10 -3 to about 30 × 10 -3 times the outer diameter of the screws, and means for heating said extruder; (b) a heatable pump means connected to said extruder for pumping molten material from said extruder; (c) a spray tank means having means for passing a cooling fluid therethrough; and (d) a heatable atomizing means in said spray tank means and connected to said pump means for melt-spraying molten material into said spray tank means to form granules thereof; (e) said pump means being operable to pump molten material from said extruder to said atomizing means, and said spray tank means being operable to solidify the atomized material therein.
Claim 2
Dependent Claim
178 words
Apparatus for melt-spraying a material that is thermally sensitive in the molten state and has a melt viscosity of from about 0.5 to about 500 cp., which comprises (a) a multi-screw extruder for melting said material comprising intermeshing, self-cleaning screws having a clearance between the intermeshing screw shafts and a clearance between the screws and the housing of the extruder in the range of from about 4 × 10 -3 to about 30 × 10 -3 times the outer diameter of the screws, and means for heating said extruder; (b) a heatable pump means connected to said extruder for pumping molten material from said extruder; (c) a spray tank means having means for passing a cooling fluid therethrough; and (d) a heatable atomizing means in said spray tank means and connected to said pump means for melt-spraying molten material into said spray tank means to form granules thereof; (e) said pump means being operable to pump molten material from said extruder to said atomizing means, and said spray tank means being operable to solidify the atomized material therein.
Claim 3
Dependent Claim
21 words
Apparatus according to claim 1, wherein said extruder is a twin screw extruder having both shafts rotatable in the same direction.
Claim 4
Dependent Claim
14 words
Apparatus according to claim 1, wherein said pump means is a piston pump means.
Claim 5
Dependent Claim
24 words
Apparatus according to claim 1, wherein a heatable, intermediate chamber means for storing molten material is located between said extruder and said pump means.
Claim 6
Dependent Claim
14 words
Apparatus according to claim 1, wherein said atomizing means is a vortex chamber nozzle.
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) | 1981-05-29 | 1981-11-28 | 1982-05-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-29 | 1985-11-28 | 1986-05-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-29 | 1989-11-28 | 1990-05-30 | $7700.00 | Window Closed / Lapsed |