US3726484A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stepped fluid energy mill
Assignee: EIDP Inc
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Filing: 1971-10-15
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Granted: 1973-04-10
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Expires: 1991-10-15
Abstract
Abstract A fluid energy mill of the confined vortex type is provided with paraxially symmetric discontinuities projecting from each of the axial walls. These serve to reduce the high radial velocities that tend to occur near the axial walls. As a consequence, there is a reduced tendency for oversize particles to escape along the axial walls and into the product collector and product uniformities are improved.
Inventors
- 👤 G Schurr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:05
CPC Classifications
B; B02; B02C; B02C19/00; B02C19/06; B02C19/061
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
20 words
Mill according to claim 1 wherein the discontinuities are defined by surfaces intersecting at an angle of less than 135*.
Claim 2
Dependent Claim
20 words
Mill according to claim 2 wherein the discontinuities are defined by surfaces intersecting at an angle of less than 90*.
Claim 3
Dependent Claim
22 words
Mill according to claim 1 wherein the discontinuities are located a distance of about 0.70 to 0.80 R from the chamber axis.
Claim 4
Dependent Claim
116 words
In a process for comminuting a material comprising pulverulent solids wherein said material is subjected to fluid energy milling in a gaseous vortex confined within a truncated cylindrical chamber, said vortex comprising a peripheral milling zone, an intermediate classifying zone and a central discharge zone, the improvement wherein at least one divergent discontinuity is symmetrically located on each axial wall of said chamber at a distance of between 0.86 R and 0.50 R from the vortical axis, where R is the radius of said chamber, the magnitude of the divergence of said discontinuity being such as to create at least an increase in paraxial height of said milling/zone at said discontinuities of at least 5 percent.
Claim 5
Dependent Claim
26 words
Process according to claim 5 wherein at least one discontinuity is provided for each axial wall at a distance of 0.70-0.80 R from the vortical axis.
Claim 6
Dependent Claim
10 words
Process according to claim 5 wherein the material is TiO2.
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) | 1976-04-09 | 1976-10-09 | 1977-04-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-04-09 | 1980-10-09 | 1981-04-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-04-09 | 1984-10-09 | 1985-04-10 | $7700.00 | Window Closed / Lapsed |