US3861753A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of and apparatus for discharging pulverulent material from silos or the like
Assignee: Azo Maschinenfabrik Adolf Zimmermann GmbH
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Filing: 1972-07-17
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Granted: 1975-01-21
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Expires: 1992-07-17
Abstract
Abstract A method of discharging pulverulent material, more particularly material having poor flow characteristics, from silos or similar pressureless containers, the material being loosened in the region of the discharge point by means of compressed air introduced in pulses from below, the method being characterized in that the air is supplied at intervals of some tens of seconds in pressure pulses of from 1 atmosphere gauge for periods of up to a few tenths of a second. Apparatus for carrying out the method comprises a pneumatic or mechanical discharge device comprising an air permeable loosening base and a valve controlling the compressed air pulses, the valve having opening times which are adapted to be preset and the time control system for the opening intervals.
Inventors
- 👤 Adolf Lesk
- 👤 Adolf Zimmerman
- 👤 Otmar Link
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 13:57
CPC Classifications
B; B65; B65D; B65D88/00; B65D88/54; B65D88/72
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
122 words
A method of discharging pulverent material from a container comprising: passing the material through a discharge opening of the container, loosening the material in the area of the discharge opening by introducing pressurized gas pulses of predetermined time duration and at predetermined time intervals into said material, wherein the predetermined time interval between the pulses is at least ten times the predetermined time duration of each pulse, and removing the material from the discharge opening by means of a suction conveyor installation, and controlling the predetermined time interval between the pulses as a function of the pressure in said suction conveyor installation such that the frequency of the pulses is changed in response to changes in pressure in said suction conveyor installation.
Claim 2
Independent Claim
122 words
A method of discharging pulverent material from a container comprising: passing the material through a discharge opening of the container, loosening the material in the area of the discharge opening by introducing pressurized gas pulses of predetermined time duration and at predetermined time intervals into said material, wherein the predetermined time interval between the pulses is at least ten times the predetermined time duration of each pulse, and removing the material from the discharge opening by means of a suction conveyor installation, and controlling the predetermined time interval between the pulses as a function of the pressure in said suction conveyor installation such that the frequency of the pulses is changed in response to changes in pressure in said suction conveyor installation.
Claim 3
Dependent Claim
27 words
A method as claimed in claim 1 in which additional air is added for capacity control purposes in known manner to the suction flow from the silo.
Claim 4
Dependent Claim
32 words
A method according to claim 1, wherein the predetermined time interval between pulses is at least 10 seconds, and wherein the predetermined time duration of each pulse is less than 1 second.
Claim 5
Dependent Claim
22 words
A method according to claim 3 wherein said predetermined time duration of each pulse is greater than one tenth of a second.
Claim 6
Dependent Claim
18 words
A method according to claim 4, wherein said pressurized gas pulses are introduced into said material from below.
Claim 7
Dependent Claim
18 words
A method according to claim 5, wherein said pressurized gas pulses are introduced immediately adjacent said discharge opening.
Claim 8
Dependent Claim
31 words
A method according to claim 6, further comprising introducing a mechanical movement into the material to aid in loosening the material, said mechanical movement being introduced only adjacent the discharge opening.
Claim 9
Dependent Claim
26 words
A method according to claim 7, wherein said mechanical movement is introduced by a gas permeable member which is moved in response to said gas pulses.
Claim 10
Dependent Claim
14 words
A method according to claim 7, wherein said pressurized gas pulses are air pulses.
Claim 11
Dependent Claim
14 words
A method according to claim 3, wherein said pressurized gas pulses are air pulses.
Claim 12
Dependent Claim
18 words
A method according to claim 1, wherein said pressurized gas pulses are introduced into said material from below.
Claim 13
Dependent Claim
18 words
A method according to claim 11, wherein said pressurized gas pulses are introduced immediately adjacent said discharge opening.
Claim 14
Dependent Claim
31 words
A method according to claim 1, further comprising introducing a mechanical movement into the material to aid in loosening the material, said mechanical movement being introduced only adjacent the discharge opening.
Claim 15
Dependent Claim
34 words
A method according to claim 1, wherein the time interval between the pulses is controlled such that the frequency of pulses becomes greater as the height of the material in the container is decreased.
Claim 16
Dependent Claim
44 words
A method according to claim 1, wherein the time interval between the pulses is controlled such that the frequency of the pulses increases with a change in pressure in said suction conveyor installation corresponding to a decrease in the rate of material conveyance thereby.
Claim 17
Dependent Claim
133 words
Apparatus for discharging pulverized material from a container, comprising: a discharge opening in said container, loosening means for loosening the material in the area of the discharge opening by introducing pressurized gas pulses of predetermined time duration and at prEdetermined time intervals into said material, control means for controlling the pulses such that the predetermined time interval between the pulses is at least ten times the predetermined time duration of each pulse, and a suction conveyor installation for removing the material from the discharge opening, wherein said control means includes means responsive to the pressure at the outlet end of said suction conveyor installation for controlling the predetermined time interval between said pulses such that the frequency of said pulses is changed in response to changes in the pressure at said outlet end.
Claim 18
Dependent Claim
133 words
Apparatus for discharging pulverized material from a container, comprising: a discharge opening in said container, loosening means for loosening the material in the area of the discharge opening by introducing pressurized gas pulses of predetermined time duration and at prEdetermined time intervals into said material, control means for controlling the pulses such that the predetermined time interval between the pulses is at least ten times the predetermined time duration of each pulse, and a suction conveyor installation for removing the material from the discharge opening, wherein said control means includes means responsive to the pressure at the outlet end of said suction conveyor installation for controlling the predetermined time interval between said pulses such that the frequency of said pulses is changed in response to changes in the pressure at said outlet end.
Claim 19
Dependent Claim
39 words
Apparatus according to claim 16, wherein said control means includes means assuring that the predetermined time interval between the pulses is at least 10 seconds and that the predetermined time duration of each pulse is less than a second.
Claim 20
Dependent Claim
22 words
Apparatus according to claim 17, wherein said loosening means is arranged for introducing said pressurized gas pulses into said material from below.
Claim 21
Dependent Claim
17 words
Apparatus according to claim 18, wherein said pressurized gas pulses are introduced immediately adjacent said discharge opening.
Claim 22
Dependent Claim
25 words
Apparatus according to claim 16 further comprising means for introducing a mechanical movement into the material to aid the gas pulses in loosening the material.
Claim 23
Dependent Claim
25 words
Apparatus according to claim 20, wherein said mechanical movement is introduced by a gas permeable member which is moved in response to said gas pulses.
Claim 24
Dependent Claim
13 words
Apparatus according to claim 21, wherein said pressurized gas pulses are air pulses.
Claim 25
Dependent Claim
17 words
Apparatus according to claim 21, wherein said control means includes a valve controlling the compressed gas pulses.
Claim 26
Dependent Claim
14 words
Apparatus according to claim 23, wherein said gas permable member is of flexible construction.
Claim 27
Dependent Claim
13 words
Apparatus according to claim 24, wherein said gas permeable member consist of fabric.
Claim 28
Dependent Claim
22 words
Apparatus according to claim 23, wherein said gas permeable member is attached at a container outer wall and adjacent the discharge opening.
Claim 29
Dependent Claim
49 words
Apparatus according to claim 26, wherein said discharge opening is located at the bottom of the container at a central part of the container, and wherein the distance between the gas permeable member and a bottom base of said container decreases in the outward direction from the discharge opening.
Claim 30
Dependent Claim
28 words
Apparatus according to claim 27, wherein said loosening means includes means for introducing said gas pulses into said container between said bottom base and said gas permeable member.
Claim 31
Dependent Claim
33 words
Apparatus according to claim 28, wherein said bottom base is conical in shape and surrounds the discharge opening, and wherein said gas permeable member is annular shaped and positioned above said bottom base.
Claim 32
Dependent Claim
35 words
Apparatus according to claim 16, wherein said suction conveyor installation includes a suction pipe leading away from the discharge opening and an adjustable area aperture in said suction pipe for controlling the suction pressure therein.
Claim 33
Dependent Claim
41 words
Apparatus according to claim 30, wherein said aperture in said suction pipe is controlled in dependence on the quantity of said material separated from the stream of material in said suction pipe by means detecting the amount of said separated material.
Claim 34
Dependent Claim
24 words
Apparatus according to claim 16, wherein said control system includes means for maintaining a control valve for said gas pulses at constant opening intervals.
Claim 35
Dependent Claim
85 words
Apparatus according to claim 16, wherein said control system includes a control valve directly controlling said gas pulses and means for maintaining said control valve with constant predetermined time duration opening intervals such that the predetermined time duration for each of the pulses is constant, and wherein said means responsive to the pressure at the outlet end of said suction conveyor installation controls the predetermined time intervals between pulses by directly controlling the time interval between closing of said valve and the next opening thereof.
Claim 36
Dependent Claim
45 words
ApParatus according to claim 16, wherein said control means includes means for automatically increasing the frequency of said pulses in response to changes in pressure at said outlet end which correspond to a decrease in the amount of material being conveyed by the conveyor installation.
Claim 37
Dependent Claim
22 words
Apparatus according to claim 16, wherein said loosening means is arranged for introducing said pressurized gas pulses into said material from below.
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) | 1978-01-20 | 1978-07-22 | 1979-01-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-20 | 1982-07-22 | 1983-01-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-20 | 1986-07-22 | 1987-01-21 | $7700.00 | Window Closed / Lapsed |