US3924814A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Arrangement in grinding mills
Assignee: Boliden AB
•
Filing: 1974-08-23
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Granted: 1975-12-09
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Expires: 1994-08-23
Abstract
Abstract A material discharging device for a drum-type continuous grinding mill having an end wall associated with outlet means for discharging from the mill grinding chamber a relatively finely ground material and a mixed material containing both relatively finely ground material and relatively coarse material. The mixed material outlet means comprises outlet openings connecting the chamber with duct means for carrying the mixed material discharged through said outlet openings to an axial discharge pipe. The discharge pipe is associated with a two-way valve, the one setting of which returns the arriving mixed material to the chamber and the other setting discharges the arriving mixed material from the mill shielded by said discharge pipe from the flow of relatively finely ground material leaving the mill.
Inventors
- 👤 Per Anders Herman He Fahlstrom
- 👤 Erik Alfon Jonsson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 00:28
CPC Classifications
B; B02; B02C; B02C17/00; B02C17/18
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
175 words
A device in a drum mill for continuous grinding and of the type including an essentially cylindrical casing and end walls, at the ends of said casing, one end wall being associated with outlet means for discharging from the grinding chamber of said mill a relatively finely ground material and a mixed material containing both relatively finely ground material and relatively coarse pieces of material, at least the outlet means for the mixed material including a number of outlet openings connecting the grinding chamber with at least one duct for carrying the mixed material discharged from the grinding chamber towards the centre of said one end wall, wherein said duct in the central region of said one end wall opens out into a discharge pipe which is associated with a two-way valve for conducting the mixed material arriving from said duct either back again to, or in a direction from the grinding chamber and which shields the outgoing flow of mixed material from the flow of relatively finely ground material discharged from the grinding chamber.
Claim 2
Independent Claim
175 words
A device in a drum mill for continuous grinding and of the type including an essentially cylindrical casing and end walls, at the ends of said casing, one end wall being associated with outlet means for discharging from the grinding chamber of said mill a relatively finely ground material and a mixed material containing both relatively finely ground material and relatively coarse pieces of material, at least the outlet means for the mixed material including a number of outlet openings connecting the grinding chamber with at least one duct for carrying the mixed material discharged from the grinding chamber towards the centre of said one end wall, wherein said duct in the central region of said one end wall opens out into a discharge pipe which is associated with a two-way valve for conducting the mixed material arriving from said duct either back again to, or in a direction from the grinding chamber and which shields the outgoing flow of mixed material from the flow of relatively finely ground material discharged from the grinding chamber.
Claim 3
Dependent Claim
46 words
A device according to claim 1, wherein the discharge pipe at least along a portion of its length extends essentially coaxially inside an outer pipe for discharging the relatively finely ground material from the mill, said pipes each opening out into its own material receiving device.
Claim 4
Dependent Claim
33 words
A device according to claim 1, wherein the discharge pipe for mixed material is provided with sieve openings to lead liquid and finely particulate material from the mixed material passing through said pipe.
Claim 5
Dependent Claim
27 words
A device according to claim 3, wherein said openings are arranged in a portion of the discharge pipe for mixed material surrounded by an outer discharge pipe.
Claim 6
Dependent Claim
39 words
A device according to claim 4, wherein the discharge pipe for mixed material is coordinated with shielding means to hinder the inflow of fine material and liquid from the outer discharge pipe into the discharge pipe for mixed material.
Claim 7
Dependent Claim
35 words
A device according to claim 3, wherein the discharge pipe for mixed material at least in the region of said sieve openings is provided with means for slowing down the flow of the mixed material.
Claim 8
Dependent Claim
43 words
A device according to claim 1, wherein the valve comprises an adjustable valve member which is connected, via a power transferring device extending coaxially with and through the discharge pipe for mixed material, to a valve setting device located outside said discharge pipe.
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) | 1978-12-08 | 1979-06-09 | 1979-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-08 | 1983-06-09 | 1983-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-08 | 1987-06-09 | 1987-12-09 | $7700.00 | Window Closed / Lapsed |