US3774855A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Grinding method and vibrating mill for performing this method
Assignee: KLOCHER HUMBOLDT DEUTZ AG
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Filing: 1971-10-12
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Granted: 1973-11-27
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Expires: 1991-10-12
Abstract
Abstract A device is described for fine grinding of plastics in which the horizontally mill is charged with the plastic to be ground and with liquid nitrogen for making the plastic brittle. The grinding chamber contains an assembly of loose grinding rods. The rods are somewhat shorter than the length of the grinding chamber, whereby during the operation of the mill at least a few of the rods will strike against the end walls of the grinding chamber and transfer to these end walls, which are grounded, the electrostatic charges formed on the surface of the particles of the ground plastic and which by said rods are conducted to said end walls and from there to the ground.
Inventors
- 👤 M Wolf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 13:40
CPC Classifications
B; B02; B02C; B02C17/00; B02C17/14; B02C18/00; B02C18/06; B02C18/14; B02C18/148; B02C23/00; B02C23/06; Y; Y10; Y10S; Y10S241/00; Y10S241/37
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
123 words
A vibrating grinding mill for fine-grinding material such as plastics in which the material to be ground is chilled by a liquid nitrogen, comprising: a grinding chamber in which the material is ground and which is mounted to be vibrated; an assembly of loose metallic grinding rods having a length slightly shorter than the length of said grinding chamber; and means grounding at least one end wall of the chamber the length of said rods being such that the ends of the rods strike against the end walls of the grinding chamber during the grinding operation so as to lead away the electrostatic charges formed on the particles of the ground material and transferred to said grinding rods through the grounded end wall.
Claim 2
Dependent Claim
123 words
A vibrating grinding mill for fine-grinding material such as plastics in which the material to be ground is chilled by a liquid nitrogen, comprising: a grinding chamber in which the material is ground and which is mounted to be vibrated; an assembly of loose metallic grinding rods having a length slightly shorter than the length of said grinding chamber; and means grounding at least one end wall of the chamber the length of said rods being such that the ends of the rods strike against the end walls of the grinding chamber during the grinding operation so as to lead away the electrostatic charges formed on the particles of the ground material and transferred to said grinding rods through the grounded end wall.
Claim 3
Dependent Claim
132 words
A vibrating grinding mill comprising: means forming a horizontally disposed vibrating grinding chamber having a circumferential wall and end walls; an assembly of loose, parallel metallic grinding rods in said grinding chamber having a length being slightly less than the length of said grinding chamber; driving means connected to the chamber for vibrating said chamber; and means grounding at least one of said chamber end walls whereby during operation of the mill at least some of said grinding rods engage against the grounded end wall so as to lead away the electrostatic charges formed on the particles of the ground material and transferred to said grinding rods, the length of said rods being such that the ends of the rods strike against the end walls of grinding chamber during the grinding operation.
Claim 4
Dependent Claim
132 words
A vibrating grinding mill comprising: means forming a horizontally disposed vibrating grinding chamber having a circumferential wall and end walls; an assembly of loose, parallel metallic grinding rods in said grinding chamber having a length being slightly less than the length of said grinding chamber; driving means connected to the chamber for vibrating said chamber; and means grounding at least one of said chamber end walls whereby during operation of the mill at least some of said grinding rods engage against the grounded end wall so as to lead away the electrostatic charges formed on the particles of the ground material and transferred to said grinding rods, the length of said rods being such that the ends of the rods strike against the end walls of grinding chamber during the grinding operation.
Claim 5
Dependent Claim
95 words
A vibrating grinding mill constructed in accordance with claim 2: wherein the mill includes a second horizontally disposed vibrating grinding chamber having a circumferential wall and end wall; an assembly of loose parallel metallic grinding rods in said second grinding chamber having a length being slightly less than the length of the grinding chamber; means grounding at least one end wall of said second grinding chamber; said driving means being connected to both of said chambers; resilient support means supporting said chambers; and a passage communicating between said chambers for the flow of material therebetween.
References Cited (Backward Citations)
US1744582A
Cited
DE560412C
Cited
US2760727A
Cited
US2778577A
Cited
US2919862A
Cited
US2879005A
Cited
US2922588A
Cited
US3295771A
Cited
US3650482A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-26 | 1977-05-28 | 1977-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-26 | 1981-05-28 | 1981-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-26 | 1985-05-28 | 1985-11-27 | $7700.00 | Window Closed / Lapsed |