US3713552A

US3713552A - Mechanized storage silo

Info

Publication number: US3713552A
Application number: US00073318A
Authority: US
Inventors: A Schnyder
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-09-18
Filing date: 1970-09-18
Publication date: 1973-01-30
Anticipated expiration: 1990-01-30

Abstract

A symmetrically shaped storage vessel for particulate material which material to be stored is introduced into the upper portion of the vessel and evenly distributed on a bed of the material therein by a rotating horizontally extending conveyor assembly. The lower portion of the storage vessel is provided with V-shaped wall assemblies terminating in horizontally disposed decks. Adjacent to the decks are rotating circular chute assemblies into which the particulate material is discharged by plows traversing the decks. At selective locations, the particulate material drops onto conveyor belts from the chutes, and eventually is passed from the storage vessel.

Description

United States atent n 1 Schnyder 1 Jan.30,1973

[541 MECHANIZED STORAGE SILO [76] Inventor: Aux P. Schnyder, 146 Cherry Lane,

Teaneck, NJ. 07666 [22] Filed: Sept. 18, 1970 [21] Appl. No.: 73,318

FOREIGN PATENTS OR APPLICATIONS 1,109,091 6/1961 Germany ..214/17 DA Primary ExaminerRobert G. Sheridan Att0rneyMarn & Jangarathis [57] ABSTRACT A symmetrically shaped storage vessel for particulate material which material to be stored is introduced into the upper portion of the vessel and evenly distributed on a bed of the material therein by a rotating horizontally extending conveyor assembly. The lower portion of the storage vessel is provided with V-shaped wall assemblies terminating in horizontally disposed decks. Adjacent to the decks are rotating circular chute assemblies into which the particulate material is discharged by plows traversing the decks. At selective locations, the particulate material drops onto conveyor belts from the chutes, and eventually is passed from the storage vessel.

9 Claims, 6 Drawing Figures PAIENTEDJmoms 3.713.552

sum 1 or 4 Aux P. Schnyder Maya/1 4mm;

AT TORNEYS PATENIEDmaoms 3,713,552

SHEET 2 OF 4 INVENTOR Aux P. Schnyder ATTORNEYS PATENTEDJAN 30 I975 SHEET 3 [IF 4 Fig. 3.

r m R V. m Ms P IX u A ATTORNEYS PATENTEDJAH 30 1975 SHEEI [1F 4 INVENIOR.

Aux P. Schnyder ATTORNEYS MECHANIZED STORAGE SILO This invention relates to a storage structure, and more particular to a storage structure for dry particulate material, such as woodchips and the like.

The storage structure of this invention is applicable to the storage of particulate material, however, to facilitate an understanding, the description relates to the storage of woodchips. In pulp and paper plants, woodchips to be processed are stored in open chip storage (OCS) areas in a plurality of piles prior to passage to the digester section of the plant. woodchips may be obtained from pulpwood or from the residue of sawmills and other wood-working plants. As required, the woodchips are removed from the piles in the OCS areas by bulldozing operations and are unloaded on conveyor devices for passage to the digesters. Such bulldozing operation results in the fringing and splitting of such chips thereby reducing pulp yields. Additionally, the practical impossibility of thoroughly collecting all of the chip passed to such ground storage reduces yields. Foreign materials are necessarily, also picked up during bulldozing operation which foreign material will be passed to the digester and subsequent pulp processing operations of the plant.

It is an object of the present invention to provide an improved storage silo into which particulate material, such as woodchips and the like, may be accumulated and stored, and from which the particulate material may be withdrawn and passed to subsequent operations.

Another object of this invention is to provide an improved storage silo for woodchips which substantially minimizes damage to the woodchips during transfer handling from OCS areas by eliminating bulldozing operations as well as to reduce losses by windage and the practical impossibility of thorough pick-up from ground storage.

Still another object of this invention is to provide an improved storage silo for woodchips which adds to the efficiency and flexibility of operations for pulp preparation.

A still further object of the invention is to provide an improved storage silo for particulate material, such as woodchips and the like, which reduces space requirements for storage as compared with open storage.

Briefly, these and other objects of the invention are accomplished by a storage silo having a cylindrical container positioned on a supporting structure. The container is generally constructed of steel reinforced tile with a support structure of steel reinforced concrete. The container may be enclosed at the top by a roof and is provided with a trussed bridge for supporting a feed conveyor and an underlying distributing conveyor whereby the chips are distributed evenly over the level of the chips within thecontainer. The'structure supporting the cylindrical container is generally circular and conically shaped and is formed with a discharge deck. An inner side wall is similarly formed about the central axis of the container. Intermediate the support structure and the inner side wall, there is provided an upright conically shaped ring structure forming therewith a restricted discharge opening to the discharge deck. In juxtaposition to the discharge deck is a drive means to which is connected a carrousel" conveyor and a close fitting plow which travels about the discharge deck to push the particulate material therefrom into the carrousel conveyor. The particulate material is carried. to a discharge station of the carrousel conveyor from which the material is withdrawn and passed, such as by conveyor means, to subsequent operations. Provisions are made to spray a liquid, such as water, onto the bed of material in the silo. The silo is also designed to permit the introduction of a gas, such as air beneathv the bed of material therein to aerate the same.

It will be apparent that the residence time of the chips in the storage silo may be closely controlled, and that uniform equal distribution of chips into the silo will inhibit unequal packing leading to bridging at the discharge end. Additionally, there will be minimal damage to and losses of the material. Power requirements for the drive means are substantially reduced as compared to pneumatic handling devices with concomitant reduction in maintenance and repairs. With large storage volume, greater efficiency and flexibility of material preparation are achieved provided there is adequate capacity for bailing and chipping. With the storage silo of the present invention, daily inventory of woodchips may be fairly accurately gauged as compared to estimating the quantity of chips in the OCS areas. Operation of the silo may be easily controlled by automated devices with no requirement for visual observation of the silo from the digester house or woodroom, since television transmitters may be positioned in the storage area of the silo.

The invention will become apparent from the following description when taken. with reference to the attached drawings wherein;

FIG. 1 is a partial schematic and cross-sectional elevational view of one embodiment of a storage silo of this invention,

FIG. 2 is a partial cross-sectional and schematic view of the storage silo taken along the line 2-2 of FIG. 1

FIG. 3 is a partial, enlarged and detailed cross-sectional view of the drive, plow and carrousel means taken along the line 33 of FIG. 2,

FIG. 4 is a partial cross-sectional view of the drive, plow and carrousel means taken along the line 4-4 of FIG. 3,

FIG. 5 is a partial schematic and cross-sectional isometric. view of a storage silo of this invention, and

FIG. 6 is a partial schematic and cross-sectional view of another embodiment of a storage silo of this invention.

Referring now to the drawing, particularly FIGS. 1 and 2, wherein like reference numerals indicate like parts throughout, there is provided a storage silo or loft, generally indicated as 10, comprised of a frustoconically-shaped outer base wall 11 position on a suitable foundation and provided with ingress and egress passages (not shown). A cylindrically shaped side wall 12, which may be provided with a roof (not shown), is mounted on and affixed to the upper portion of the base wall 11. The side wall 12 may be formed of steel reinforced tiles, with the base wall 11 being cast-inplace. The roof (not shown) may be formed of corrugated steel panels and is positioned on and suitably supported by side wall 12 about the top portion of the silo 10. A trussel bridge 13 is positioned above and supported by the cylindrical side wall 12 within which is disposed a distributing conveyor 14 for passing particulate material, such as wood chips, into the storage silo 10, as more fully hereinafter described.

Centrally positioned on the common foundation within the storage silo 10, is a cylindrical and inverted, frustoconically shaped inner base wall 15. A hollow cylindrically shaped support column 16 is mounted on the upper end on the base wall 15 and is provided with an inner spiral riser assembly 17. A plurality of horizontally disposed l-beams 18 are positioned on and affixed to said support column 16. A circular support rail 19 is mounted to the outer portion of the l-beams 18. Mounted on said support column 16 is a chip distributor 20 including a vertically extending elongated deflector 21 extending through a chute 22 into a cylindrical hopper 23 mounted to the trussel bridge 13. Positioned below the discharge end of the chute 22, there is provided a rotating distributor conveyor, generally indicated as 24, which is intermediately supported by a roller assembly 25 affixed to conveyor 24 and rides on the rail 19. The conveyor 24 includes a tail pulley as a drive means and an adjustable end pulley for belt stretching and extends horizontally towards the side wall 12 of the silo catenarially suspended (schematically illustrated) on the roller assembly 25 by a suitable counterweight 27 (schematically illustrated). The conveyor 24 is provided with a plurality of deflectors or spill gates 28 along its length to distribute uniformly the chips over the area of the silo 10, as well as spray nozzles 29 in fluid communication with a fluid supply conduit (not shown).

The base wall 11 is formed with a horizontally disposed, discharge deck 30 extending inwardly at the lower portion of the wall 11. The inner wall is similarly provided with a horizontally disposed discharge deck 31 extending outwardly at the lower portion thereof towards the base wall 11. Centrally positioned between the inner and outer base wall 11 and 12, there is provided a ring-shaped, conical deflector assembly 32 extending upwardly from a point above about the midpoint of

discharge decks

30 and 31 and supported by structural frames (not shown) from the common foundation forming discharge openings therebetween. The base wall 11, inner wall 12 and deflector assembly 32 separate the silo 10 into an upper storage zone 34 and a lower service vault area 35. Provided within the vault area 35 are intermediate collecting conveyors 36 which are arranged to pass particulate material to a main removal conveyor 37, as more fully hereinafter described. The lower vault area 35 is provided with a blower means, schematically illustrated as 38, to place the vault area 35 under a positive pressure whereby a gas, such as air, may be caused to circulate through the discharge openings formed by

discharge decks

30 and 31, and deflector assembly 32.

Referring to FIGS. 3 and 4, there is provided a plow and collecting assembly, generally indicated as 40. The plow and collecting assembly 40 includes a base 41; a motor 42; a gear reducer 43; a collecting carrousel, generally indicated as 44; a plow support assembly, generally indicated as 45; and a plow 56. The motor 42 and the vertically disposed reducer gear 43 operatively connected to one another, are positioned on the base 41. Rails 47 are mounted to base 48 suitably supported (not shown) adjacent the base 41. A fixed bottom plate 49 is framed or mounted between the rails 47, with discharge openings 50 provided therein (as illustrated in FIG. 2). The rotating portion of the carrousel 44 consists of parallel and vertically disposed

plates

51 and 52 interconnected by a plurality of vertical flights 53 perpendicularly mounted to and evenly positioned between

plates

51 and 52 around the circumference of the carrousel 44. A pinion 53a mounted to a shaft 54 of the gear reducer 40 engages a pin type rack belt 55 affixed to the outer portion of plate 51 of the carrousel 44. Above the rack belt 55, there is affixed on the plate 51, a second rack belt 56.

Positioned above the carrousel 49 is plow support assembly 45 including

plow support plates

57 and 58 to which the horizontally disposed plow 56 is connected by an upper support member 59. Positioned on the lower portion of the plate 57, there are provided a plurality of guide rolls members generally indicated as 60 and 61, each including a mounting member 62, a shaft 63, and support rollers 64. The rollers 64 run along an interior side wall of the plate 51 of the carrousel 44 and contribute to horizontal stability. About the surface of the plate 57 opposite the plow 51, a pin type rack belt 65 is provided, which provides a mechanical interlock with the otherwise independent plow assembly to the carrousel assembly 44, as hereinafter described. A pinion gear 66 and drive gear 67 are mounted on a shaft 68 and rotatably supported by member 69. A gear 70 and a pinion gear 71 are mounted on a shaft 72 rotatably supported by member 73. The gear 70 engages the drive gear 67 whereas the pinion gear 71 engages the rack belt 65 mounted on plate 57.

The plow 56 is preferably positioned at a forward lead angle of about 45 over the flat discharge band of the discharge deck 30 and terminates at the rim of the deck 30 adjacent the carrousel assembly 44. The contact surface of the plow 56 may be rounded in the 90 quadrant with the bottom portion extended. As more clearly shown in FIG. 4, the plow 56 is affixed to plow support plate 57 by upper support bar 59 and to plate 58 by

support bars

74 and 75. The lower support bars 74 and 75 are rotatably mounted on shafts 76. The shafts v76 are provided with guide rollers 78 extending over the edge of discharge deck 30 and support rollers 79 running on the surface of discharge deck 30.

The storage and removal of particulate material of the storage silo 10 of the invention will be described with reference tothe handling of wood chips. It will be readily apparent that the instant invention is applicable to the handling and storage of other dry bulk particular material such as oats, wheat, rice etc., as well as ore, coal, etc. Accordingly, wood chips are placed directly or indirectly onto conveyor 14 at a unloading location remote from the storage silo 10, and passed thereon to chip hopper 23 from which the chips are discharged through chute 21 onto rotating conveyor assembly 24.

The chips are passed along the conveyor and are evenly distributed into the storage area 34-of the silo 10 by cooperation of the spaced apart spill gates 28 positioned along the conveyor and the ability of the conveyor assembly 24 to rotate continuous by through 360. The amount of chips in storage may be verified from a remote location, such as by television. The resulting even distribution of chips within the silo avoids local compaction. The even downward flow of chips through the silo 10 (i.e., by chip withdrawal) is effected by the continuous removal of chips from the discharge decks by the plows traversing 360 (as compared to confined circular outlets in cylindrical silos).

With the motor 42 operative, the shaft 54 of the gear reducer 43 rotates causing pinion gear 53a to rotate which in turn through engagement with the pinion rack 57 effects rotation of the carrousel assembly 44. The rack 56 attached to the upper portion of plate 51 engages pinion gear 66 on shaft 68 which causes the drive gear 67 on shaft 68 to rotate in response thereto. The gear 67 is in engagement with the gear 70 affixed to shaft 72 as is pinion gear 71. The pinion gear 71 is in engagement with the pinion rack 65 on the plow support means 45 to cause the plow 56 to rotate about the deck 30 thereby sweeping chips therefrom into the receiving sections of the rotating carrousel assembly 44 formed by the

side plates

57 and 58 with vertical plates 53. The chips are moved on the plate 49 by the action of the rotating carrousel 44 until the chips pass over the opening 50 in the plate 49 thereby dropping onto conveyor 36 from which the chips are passed onto conveyor 37 and thence from the silo for further processing.

It is understood that the carrousel 44 and plow 56 may rotate in the same direction or in the opposite direction. Additionally, the carrousel assembly 44 and plow 56 may move at different velocities depending on the gearing ratio between

gears

67 and 70. The pinion gear 71 does not essentially rotate, which holds true for the associate shaft 72 and gear 70 since the rotation of shaft 68 is translated into the movement of the plow assembly about the discharge decks. The pinion gear 71 could be replaced by a horizontal bar affixed to the shaft 72 and extending between bars mounted on plate 57. The rack 65 and pinion gear 71 arrangement, however, provides flexibility in that such arrangements act to cushion the effect of any unexpected additional resistance which may be momentarily encountered by plow 56 as it sweeps across the discharge decks.

FIG. 5 partial schematically illustrates another embodiment of the invention wherein a discharge area is formed with an integral distributor 536 thereby providing two

discharge decks

531 and 534. Introduction, storage and withdrawal of the chips from the silo 510 are accomplished in a manner similar to the embodiment of FIGS. 1 to 4 with like equipment.

FIG. 6 schematically illustrates still another embodiment of the invention wherein a single discharge deck 630 is provided with the discharge area thereabove formed by the converging outer wall 611 and a centrally positioned inverted cone deflector 632. The equipment for introducing, storing and withdrawing the chip from the silo 610 are similar to the silo of FIGS. 1 to 5.

What is claimed is:

1. A storage silo for particulate material which comprises:

a container including an outer wall having an inwardly extending lower section thereof;

an interior wall sloping towards a terminal portion of said lower section of said outer wall and forming therewith a restricted discharge opening therebetween;

a deck including a discharge edge disposed below Said pe g; a collecting assembly positioned ad acent said discharge edge, said collecting assembly being comprised of a plurality of receiving sections;

a plow assembly positioned on said discharge deck and including a plow having a forward lead angle; means for rotating said conveyor assembly; and means for moving said plow assembly over said discharge deck whereby particulate material is forced over said discharge edge of said deck into said receiving section of said collecting assembly.

2. The storage silo as defined in claim 1 wherein said plow and collecting assemblies rotate with respect to one another and are mechanically interlocked to one another.

3. The storage silo as defined in claim 2 wherein the particulate material introduced into said silo is evenly distributed therein by a rotating conveyor assembly positioned in the upper portion of the container.

4. The storage silo as defined in claim 3 wherein the rotating conveyor assembly is provided with fluid spray means.

5. The storage silo as defined in claim 1 wherein said container is provided with blow means beneath said restricted openings.

6. The storage silo as defined in claim 1 wherein said container is provided with two decks, each deck provided with a plow assembly and a rotating collecting assembly.

7. The storage silo as defined in claim 1 wherein said plow is provided with a 45 lead angle to the direction of rotation.

8. The storage silo as defined in claim 1 wherein said collecting assembly is comprised of a cylindricallyshaped side wall spaced apart from a second cylindrically shaped side wall and affixed to each other by a plurality of vertically disposed plates thereby forming said receiving sections and wherein said cylindrically shaped side walls overlay a circularly shaped bottom wall, said circularly shaped bottom wall being provided with aperture means disposed above a conveyor means for withdrawing particulate material from said silo.

9. The storage silo as defined in claim 8 wherein said circularly-shaped bottom wall is provided with a plurality of apertures.

Claims

1. A storage silo for particulate material which comprises: a container including an outer wall having an inwardly extending lower section thereof; an interior wall sloping towards a terminal portion of said lower section of said outer wall and forming therewith a restricted discharge opening therebetween; a deck including a discharge edge disposed below said opening; a collecting assembly positioned adjacent said discharge edge, said collecting assembly being comprised of a plurality of receiving sections; a plow assembly positioned on said discharge deck and including a plow having a forward lead angle; means for rotating said conveyor assembly; and means for moving said plow assembly over said discharge deck whereby particulate material is forced over said discharge edge of said deck into said receiving section of said collecting assembly.

7. The storage silo as defined in claim 1 wherein said plow is provided with a 45* lead angle to the direction of rotation.

8. The storage silo as defined in claim 1 wherein said collecting assembly is comprised of a cylindrically-shaped side wall spaced apart from a second cylindrically shaped side wall and affixed to each other by a plurality of vertically disposed plates thereby forming said receiving sections and wherein said cylindrically shaped side walls overlay a circularly shaped bottom wall, said circularly shaped bottom wall being provided with aperture means disposed above a conveyor means for withdrawing particulate material from said silo.