US3883011A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hopper installation
Assignee: Associated Portland Cement Manufacturers Ltd
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Filing: 1973-03-14
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Granted: 1975-05-13
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Expires: 1993-03-14
Abstract
Abstract A method of and apparatus for handling grab-unloaded particulate material in a hopper installation comprises passing the grab through an intake section open at the top and into a discharge chamber at its lower end of enlarged cross-sectional area. In one arrangement dust-laden air is withdrawn from said chamber through outlet ports by an extractor to create a circulatory air flow therein and set up in the central zone a partial vacuum. In a second arrangement the dust-laden air is recirculated through inlet and outlet ports thus maintaining a central zone at neutral pressure. By effecting discharge of the grab in the central zone the dustladen air is substantially confined within the hopper body. The apparatus can be operated at lower rates of air extraction not substantially exceeding 12,000 cu.ft/min.
Inventors
- 👤 Anthony Robin Pennell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 07:54
CPC Classifications
B; B65; B65G; B65G69/00; B65G69/18; B65G69/185; B65G69/186
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
148 words
In a hopper installation for handling particulate material containing a fine dust fraction comprising a hopper body which is open at its upper end to receive a grab containing material to be discharged, the hopper having a bottom discharge opening, the improvement in which the hopper body comprises an elongated intake section which is open at its upper end and which is conneCted at its lower end with and opens into a discharge chamber of increased cross section, said intake section providing an unobstructed passage for introduction therethrough into the chamber of the grab containing material to be discharged, and air extracting means connected to said chambers for withdrawing air from the wall area of said chamber to produce an air flow pattern surrounding a neutral or negative pressure central zone of minimum flow therein within which the grab or bucket can be lowered to release its contents.
Claim 2
Dependent Claim
148 words
In a hopper installation for handling particulate material containing a fine dust fraction comprising a hopper body which is open at its upper end to receive a grab containing material to be discharged, the hopper having a bottom discharge opening, the improvement in which the hopper body comprises an elongated intake section which is open at its upper end and which is conneCted at its lower end with and opens into a discharge chamber of increased cross section, said intake section providing an unobstructed passage for introduction therethrough into the chamber of the grab containing material to be discharged, and air extracting means connected to said chambers for withdrawing air from the wall area of said chamber to produce an air flow pattern surrounding a neutral or negative pressure central zone of minimum flow therein within which the grab or bucket can be lowered to release its contents.
Claim 3
Dependent Claim
40 words
A hopper installation as claimed in claim 1, wherein the discharge chamber has ports provided in the wall thereof, said ports being connected by a pipeline to an air extractor and being peripherally spaced to produce said air flow pattern.
Claim 4
Dependent Claim
177 words
In a hopper installation for handling particulate materials containing a fine dust fraction comprising a hopper body which is open at its upper end to receive a grab containing material to be discharged, the hopper having a bottom discharge opening, the improvement in which the hopper body comprises an elongated intake section which is open at its upper end and which is connected at its lower end with and opens into a discharge chamber of increased cross-section, said intake section providing an unobstructed passage for introduction therethrough of the grab containing material to be discharged, air inlet and air outlet ports located respectively in upper and lower wall areas of the chamber and arranged symmetrically with respect to each other; and air extraction means including pipelines connected to said outlet ports for withdrawing air from said chamber and pipelines connected to said inlet ports for recirculating the withdrawn air through said chamber to produce an air flow pattern surrounding a neutral pressure zone within the chamber into which the grab can be lowered to release its contents.
Claim 5
Dependent Claim
177 words
In a hopper installation for handling particulate materials containing a fine dust fraction comprising a hopper body which is open at its upper end to receive a grab containing material to be discharged, the hopper having a bottom discharge opening, the improvement in which the hopper body comprises an elongated intake section which is open at its upper end and which is connected at its lower end with and opens into a discharge chamber of increased cross-section, said intake section providing an unobstructed passage for introduction therethrough of the grab containing material to be discharged, air inlet and air outlet ports located respectively in upper and lower wall areas of the chamber and arranged symmetrically with respect to each other; and air extraction means including pipelines connected to said outlet ports for withdrawing air from said chamber and pipelines connected to said inlet ports for recirculating the withdrawn air through said chamber to produce an air flow pattern surrounding a neutral pressure zone within the chamber into which the grab can be lowered to release its contents.
Claim 6
Dependent Claim
23 words
A hopper installation as claimed in claim 3 in which each outlet port is provided with a series of transversely extending boxed apertures.
Claim 7
Dependent Claim
33 words
A hopper installation as claimed in claim 3 in which the inlet ports include pipes projecting downwardly into the chamber so as to induce a toroidal pattern of air flow within the chamber.
Claim 8
Dependent Claim
38 words
A hopper installation as claimed in claim 3, in which the means for circulating dust-laden air includes a fan whose inlet side is connected to each outlet port and whose outlet side is connected to each inlet port.
Claim 9
Dependent Claim
32 words
A hopper installation is claimed in claim 3, in which the chamber is provided with an open-meshed grid located beneath the outlet ports for cooperation with the grab to initiate opening thereof.
Claim 10
Dependent Claim
181 words
In a hopper installation for handling particulate materials containing a fine dust fraction comprising a hopper body which is open at its upper end to receive a grab containing material to be discharged, the hopper having a bottom discharge opening, the improvement in which the hopper body comprises an elongated intake section which is open at its upper end and which is connected at its lower end with and opens into a discharge chamber of increased and rectangular cross-section, said intake section providing an unobstructed passage for introduction therethrough of the grab containing material to be discharged, four air inlet ports are located at the corners of the chamber and four air outlet ports are placed centrally of the wall areas of the chamber; and air extraction means including pipelines connected to said outlet ports for withdrawing air from said chamber and pipelines connected to said inlet ports for recirculating the withdrawn air through said chamber to produce an air flow pattern surrounding a neutral pressure zone within the chamber into which the grab can be lowered to release its contents.
Claim 11
Dependent Claim
181 words
In a hopper installation for handling particulate materials containing a fine dust fraction comprising a hopper body which is open at its upper end to receive a grab containing material to be discharged, the hopper having a bottom discharge opening, the improvement in which the hopper body comprises an elongated intake section which is open at its upper end and which is connected at its lower end with and opens into a discharge chamber of increased and rectangular cross-section, said intake section providing an unobstructed passage for introduction therethrough of the grab containing material to be discharged, four air inlet ports are located at the corners of the chamber and four air outlet ports are placed centrally of the wall areas of the chamber; and air extraction means including pipelines connected to said outlet ports for withdrawing air from said chamber and pipelines connected to said inlet ports for recirculating the withdrawn air through said chamber to produce an air flow pattern surrounding a neutral pressure zone within the chamber into which the grab can be lowered to release its contents.
Claim 12
Dependent Claim
42 words
A hopper installation as claimed in claim 8 further comprising means for extracting at least a proportion of the volume of dust-laden air in circulation from the hopper installation so as to induce a positive in-flow of atmospheric air into the hopper.
Claim 13
Dependent Claim
20 words
A hopper installation as claimed in claim 8 in which each inlet port is placed laterally between two outlet ports.
Claim 14
Independent Claim
150 words
A method of handling particulate material containing a fine dust fraction in a hopper installation, comprising the steps of: a. passing a grab, loaded with the particulate material, through an elongated intake section of restricted area into an inner hopper chamber having a greater transverse area than that of the intake section; b. withdrawing dust-laden air from said chamber in such a manner as to set up an inner zone within said chamber at a neutral or negative pressure; c. releasing particulate material from said grab within said zone; d. recirculating to the chamber dust-laden air withdrawn therefrom. e. removing part of the circulating dust-laden air from circulation in the hopper installation so as to induce a positive in-flow of atmospheric air into the hopper; and, f. removing dust from the removed part of the circulating dust-laden air, and thereafter discharging the removed part of the air to the atmosphere.
Claim 15
Independent Claim
150 words
A method of handling particulate material containing a fine dust fraction in a hopper installation, comprising the steps of: a. passing a grab, loaded with the particulate material, through an elongated intake section of restricted area into an inner hopper chamber having a greater transverse area than that of the intake section; b. withdrawing dust-laden air from said chamber in such a manner as to set up an inner zone within said chamber at a neutral or negative pressure; c. releasing particulate material from said grab within said zone; d. recirculating to the chamber dust-laden air withdrawn therefrom. e. removing part of the circulating dust-laden air from circulation in the hopper installation so as to induce a positive in-flow of atmospheric air into the hopper; and, f. removing dust from the removed part of the circulating dust-laden air, and thereafter discharging the removed part of the air to the atmosphere.
Claim 16
Independent Claim
197 words
A method of discharging particulate materials containing a fine dust fraction from a grab into a hopper, comprising the steps of: a. providing within a hopper a chamber of relatively wide cross-section for discharge into a central zone above a predetermined level therein of particulate material from a loaded grab; b. further providing an elongated hopper intake passage of relatively narrow cross-section opening at its lower end into said chamber and open at it upper end to receive a grab; c. withdrawing air from around the wall area of said chamber immediately above said level and thereby maintaining around the inside of said chamber a pattern of flowing air characterized by a generally downward current of air adjacent and circumscribing said central zone and leaving in said central zone relatively still air at neutral or negative pressure; d. lowering a grab loaded with said particulate material through said elongated passage and into said central zone within said chamber until said predetermined level is reached, discharging the contents of the grab into the chamber and subsequently withdrawing the grab from the hopper through the elongated passage; e. with dust arising from said discharging being confined within the system.
Claim 17
Independent Claim
197 words
A method of discharging particulate materials containing a fine dust fraction from a grab into a hopper, comprising the steps of: a. providing within a hopper a chamber of relatively wide cross-section for discharge into a central zone above a predetermined level therein of particulate material from a loaded grab; b. further providing an elongated hopper intake passage of relatively narrow cross-section opening at its lower end into said chamber and open at it upper end to receive a grab; c. withdrawing air from around the wall area of said chamber immediately above said level and thereby maintaining around the inside of said chamber a pattern of flowing air characterized by a generally downward current of air adjacent and circumscribing said central zone and leaving in said central zone relatively still air at neutral or negative pressure; d. lowering a grab loaded with said particulate material through said elongated passage and into said central zone within said chamber until said predetermined level is reached, discharging the contents of the grab into the chamber and subsequently withdrawing the grab from the hopper through the elongated passage; e. with dust arising from said discharging being confined within the system.
Claim 18
Dependent Claim
21 words
A method according to claim 12, wherein said pattern of flowing air is maintained toroidal by recirculation through external piped means.
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) | 1978-05-12 | 1978-11-11 | 1979-05-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-12 | 1982-11-11 | 1983-05-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-12 | 1986-11-11 | 1987-05-13 | $7700.00 | Window Closed / Lapsed |