US3576312A

US3576312A - Method and apparatus for filling containers

Info

Publication number: US3576312A
Application number: US813112A
Authority: US
Inventors: Thomas B Sturges
Original assignee: Cherry Burrell Corp
Current assignee: Cherry Burrell Corp; Stone Container Corp
Priority date: 1969-04-03
Filing date: 1969-04-03
Publication date: 1971-04-27
Anticipated expiration: 1988-04-27
Also published as: JPS4836671B1

Abstract

A method and apparatus for filling containers, such as valve bags, with particulate material that is considered difficult to package. An inlet valve provides access to the top of a vertically disposed hopper containing a lower porous pad through which fluidizing air is injected. A horizontal filling spout extends through the sidewall near the hopper bottom, and additional air is injected into the spout and also into the upper portion of the hopper. A vibrator associated with the hopper at a location above the longitudinal center thereof applies lineal vibration to the hopper, preferably along a line at an angle to the horizontal between 35* and 55*.

Description

United States Patent [72] Inventor Thomas B. Sturges 2,609,185 9/1952 Eisner Menlo Park, Calif. 3,047,275 7/1962 Cox [21] Appl. No. 813,112 3,178,068 4/1965 Dumbaugh..... [22] Filed Apr. 3,1969 3,409,274 11/1968 Lawton {45] Patented Apr. 27, 1971 Primar y ExammerRe1naldo P. Machado [73] Ass'gnee chgm'nuneu Corporauim Attorney- Anderson, Luedeka, Fitch, Even & Tabin Chicago, Ill.

[54] METHOD AND APPARATUS FOR FILLING CONTAINERS 14 Claims 7 Drawing Figs. ABSTRACT: A method and apparatus for filling containers, such as valve bags, with particulate material that is considered [52] U.S. Cl. 259/2, m u to package Ah -n valve provides access to the top 259/12 259/29 259/72 of a vertically disposed hopper containing a lower porous pad [51] Int. Cl 1301f 11/00 through which fl idi i air is injected A horizontal fini [50] Field of Search 259/2, 4, shout extends through the sidewall near the hhhper bottom, 72, (Dlgest (Dlggst 42) and additional air is injected into the spout and also into the upper portion of the hopper. A vibrator associated with the [56] References cued hopper at a location above the longitudinal center thereof ap- UNITED STATES PATENTS plies lineal vibration to the hopper, preferably along a line at 2,605,084 7/ 1952 Reents 259/4 an angle to the horizontal between 35 and 55.

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METHOD AND APPARATUS FOR FILLING CONTAINERS This invention relates to the filling of containers with particulate material, and more particularly to methods and apparatus for filling bags with particulate products that are especially difficult to package.

Various apparatus have been developed to fill containers, such as valve bags and the like, with uniform amounts of particulate materials. One general class of apparatus of this type employs a generally vertical hopper which is fed from an overhead supply. The particulate material is maintained in a generally fluidized state within the hopper by the injection of air through a lower porous member. Such apparatus may also employ an upper zone of slightly higher pressure air which encourages the flow of the fluidized particulate material through an outlet in the vicinity in the lower end of the hopper leading to a spout which empties into the bag or container being filled. While apparatus of this general type and other similar types, which employ fluidization by air or other gas, are suitable for the packaging of many types of particulate material, there are some particulate materials which are not handled to satisfaction by such apparatus.

Different particulate materials to be packed may have different moisture contents, and the combination of moisture content and particle characteristics may produce a material that is difficult to package. Finely divided pigments, such as titanium dioxide and lead oxide of certain grades, often fall into this category. These materials oftentimes have a tendency to bridge and plug some portion of the apparatus, resulting in uneven packaging and perhaps even in shutdown of the apparatus until it is possible to manually relieve the situation. Methods and apparatus are desired for efficiently and uniformly filling bags and other containers with particulate material that is difficult to package.

The object of the present invention is to provide improved methods and apparatus for filing bags or other types of containers with particulate material. Another object is to provide an improved apparatus for filling valve bags which utilizes generally a vertical hopper wherein the particulate material is fluidized by the entry of air. A further object is to provide an improved method for fluidizing a finely divided particulate material within the vertical hopper and feeding the material in its fluidized state into a valve bag.

These and other objects of the invention will become ap parent from a reading of the following description in accordance with the accompanying drawings wherein:

FIG. I is a side elevation view of apparatus for filling valve bags embodying various features of the invention, with a support tower shown in dashed outline to improve clarity;

1 FIG. 2 is an enlarged fragmentary view illustrating generally an upper portion of the apparatus shown in FIG. 1, looking in the direction of the arrows 2-2;

FIG. 3 is an enlarged vertical section view of the spout portion of the apparatus shown in FIG. 1;

FIG. 4 is an enlarged vertical sectional view, similar to FIG. 3, of a portion of the apparatus shown in FIG. 1 associated with the spout;

FIG. 5 is an enlarged exploded perspective view of the portion of the apparatus shown in FIG. 2;

FIG. 6 is an exploded perspective view of another portion of apparatus shown in FIG. 2; and

' FIG. 7 is an enlarged sectional view taken generally along the line 7-7 of FIG. 6.

It has been found that the application of lineal vibration to the hopper section wherein fluidization of particulate material to be packed is taking place positively prevents bridging from occurring even though the characteristics of the material place it in that group of materials considered quite difficult to package. In combination with the application of lineal vibration, the application of fluidizing air to the spout itself facilitates the efficient packaging in valve bags of particulate material which is otherwise difficult to package. Moreover, by applying lineal vibration to the hopper along a line at a predetermined angle to the horizontal whileinjecting fluidizing air vertically upward from the bottom of the hopper, excellent uniform fluidation is achieved e even though working with particulate materials which are difficult to uniformly fluidize under normal circumstances.

The invention is illustrated by the apparatus 11 which is designed to fill bags of the valve-type. The apparatus 111 includes a vertically disposed hopper assembly 13, the upper end of which is closed by an upper valve assembly 15. The illustrated valve assembly 15 includes a butterfly valve utilizing a circular disc that is mounted on a shaft extending along a diametral axis; however, it should be understood that other suitable valves may be employed. An air cylinder assembly 1l7, which is connected to a suitable source of pressurized air (not shown), is mounted on the valve assembly 15. The air cylinder assembly 17 operates a link 19 affixed to the end of the shaft carrying the butterfly valve disc. Surrnounting the butterfly valve assembly I5 is an inlet section 21 which is for connection to an overhead supply of the particulate material to be packaged, as for example the lower end of a storage bin.

The hopper assembly l3, in the embodiment depicted, is supported from a tower 23, which is shown in broken lines in order to illustrate the apparatus in as uncomplicated a manner as possible. One alternative to the use of such support tower would be a framework which depends the overhead. Connection between the support tower 23 hopper assembly is made via a subframe 25 which also carries a vibrator assembly 27 and is described in more detail hereinafter.

A spout assembly 29 communicates with the lower end of the hopper 13 via a flexible coupling 31 which serves to isolate the spout from the vibration being applied to the hopper assembly during the operation of the apparatus. A lower support framework 35 carries the spout assembly 29 and a scale mechanism 37 which is disposed beneath the spout. The scale mechanism 37 employed may be of the type known in the art which contains a cradle or platform upon which the bag being filled rests. However, other suitable weighing mechanisms may be employed, including those of the type which are as sociated directly with the spout assembly.

The hopper assembly 13 includes a main portion 41 and a lower or transition portion 43, both of which are illustrated as being circular in cross section and having the same diameter. However, in instances wherein the product has a very low bulk density, an upper section may be employed which has a larger diameter. Moreover, the cross-sectional shape of the hopper may be other than circular. The

hopper portions

41 and 43 are joined together in coaxial alignment via flanges at the adjacent ends thereof. Although the hopper 13 might be made of a single section, the desired vertical height of the hopper varies for different products that are to be packaged, and the two-piece design allows the lower or transition section 43 to be of standardized length while the upper section 4] is made to a specific length for a particular job.

The lower end of the transition section 43 of the hopper is formed with an annular flange 45 which is oriented to lie in a substantially horizontal plane. Connected to this annular flange 45 is a porous member or pad 47 which closes the bottom of the hopper assembly 13. The porous pad 47 is oriented generally horizontally, and the application of air to an inlet 49 on the underside thereof results in the injection of fluidizing air vertically upward into the particulate material filling the hopper 13. The air inlet 49 is connected via a pressure-regulating valve 51, such as a needle valve, to an air supply assembly 53 which is mounted near the top of the support tower 23.

The air supply assembly 53 is also connected via a flexible tube 55 to an upper air inlet 57 which is disposed near the top of the hopper assembly 13 at a location slightly below the butterfly valve assembly 15. As is discussed in more detail hereinafter, air at a sufficient pressure to fluidize the particulate material within the hopper is injected vertically upward through the lower pad 47 in order to impart the flowable characteristics of a fluid to the material within the hopper. The fluidized material tends by gravity to seek the lowest level and flow through the spout assembly 29. The air injected into the upper inlet 57 assists this movement and assures that there is a uniform flow of fluidized particulate material from the hopper out through the spout assembly 29.

Referring more particularly to FIGS. 2 and 5, the vibrator assembly 27 is mounted on the subframe 25 which supports the hopper 13. The subframe 25 includes a base made up of a pair of parallel channels 61 to which are welded a pair of crossmembers 63 which are shown as angle iron. The subframe 25 is suitable supported at the desired vertical location, as by bolting the channels 61 to the upstanding columns of the support tower 23. Affixed to the parallel crossmembers 63 are four support discs 65, each of which carries a suitable vibration-isolator 67, such as a pneumatic mount.

The connection between the hopper assembly 13 and the subframe 25 is via a pair of

mating bracket assemblies

69 and 71, which are identical in construction and which are designed to be clamped to the outer cylindrical surface of the upper section 41 of the hopper, as hereinafter described. Each

ofthe bracket assemblies

69, 71 includes an upstanding vertical back plate 73 to which is affixed, as by welding, a pair of horizontal plates 75. A pair of braces 76 extend between the upper and lower plates 75 and are welded thereto. Each of the horizontal plates 75 contains an arcuate cutout 77 which is nearly a semicircle and which is proportioned so that the radius of the arc is equal to one-half the outer diameter of the upper section 4! of the hopper assembly. Attached to the top surface of the upper plates 75 and to the bottom surface of the lower plates 75 are a pair of clamp ring halves 79. For example, the clamp ring halves 79 may be bent from angle iron or the like and bolted to the plates 75, or a welded construction may be used.

The clamp ring halves are disposed adjacent the cutouts 77, and apertured lugs 81 affixed to each end of the clamp ring halves 79 receive volts 83 (FIG. 2) which are employed to clamp the

bracket assemblies

69 and 71 to the outer cylindrical surface of the upper section 41 of the hopper assembly 13. Affixed to the underside of the upper horizontal plate 75 of each of the bracket assemblies are a pair of support discs 85, which are suitably apertured to rest upon and connect to the upper ends of the vibration-isolators 67. Thus, it can be seen that, when the bracket assemblies are clamped to the main portion 41 of the hooper and the four vibration-isolators 67 are respectively each connected to the support discs 65 of the subframe 25 and the support discs 85 of the

bracket assemblies

69, 71, then the hopper assembly 13 is supported at its desired vertical location by the support tower 23.

As seen in FIG. 5, a plurality of holes 87 are provided in each of the backplates 73, the holes 87 being located on a circle of given diameter and individually spaced from one another by predetermined angular increments. It is via these holes 87 that the vibrator assembly 27 is mounted to the bracket assembly 69 and that a counterweight 89 is mounted to the opposite bracket assembly 71. The counterweight 89 may be simply provided with four holes which align with four ofthe holes 87 in the backplate 73 of the bracket assembly 71 so it may be simply fastened thereto by four bolts of suitable length.

The vibrator assembly 27 includes a vibrator 90 and a vibrator mounting bracket 91 by which connection between the vibrator 27 and the bracket assembly 69 is accomplished. The

' vibrator mounting bracket 91 (FIG. 6) is constructed of an upstanding plate 93 that has affixed at right angles thereto, as by welding, a support shelf 95. A pair of triangular reinforcing gussets 97 are welded therebetween and add rigidity to the overall mounting bracket 91. The upstanding plate 93 contains 16 holes disposed on a circle of a diameter equal to that upon which the holes 87 in the backplate 73 are located. Because the spacing between the holes 78 is the same as that between the holes 99, it can be seen that the plate 93 of the vibrator mounting bracket can be bolted to the backplate 73 with the support shelf 95 oriented at different desired angles to the horizontal by aligning the appropriate holes and using bolts and nuts to interconnect the plates.

The vibrator has a base 103 containing four holes 105a which are spaced apart the same distance as the innermost four holes 105 in the support shelf 95, and the vibrator 90 is thereby appropriately bolted thereto. As best seen in FIG. 6, the ends of four threaded rods 107 pass through the outermost four holes 109 in the support shelf 95 and are fastened thereto by suitable nuts on both sides of the plate 95. A motor mount 111 in the form of an apertured flat plate contains holes 113a which receive the other threaded ends of the rods 107 and is suitably fastened thereto by nuts on both sides thereof. An electric motor 113 is suitably bolted to the motor mount 111 via the four innermost holes 115 therein. A sheave 117 (FIG. 2), attached to the drive shaft of the motor 113, is connected by V-belt 119 to a sheave 121 mounted on the drive shaft 123 of the vibrator. The precise operation of the vibrator 90 is discussed hereinafter in conjunction with the overall operation of the bag-filling apparatus 11.

As seen in FIG. 4, a socket 125, which is located in a suitable aperture in the sidewall of the lower section 43 of the hopper hear the bottom thereof and welded thereto, provides the hopper lower outlet. A hose connector assembly 127 is disposed in the socket 125 and connects the hopper outlet with the flexible coupling 31 leading to the spout assembly 29. The hose connector assembly 127 includes an outer generally tubular shell 129 which fits into the socket 125 and is secured in place via an annular clamping ring 131 and bolts (not shown) which are threaded into suitable holes in the socket. An O-ring 132 seals the opening. Disposed inwardly of the shell 129 and concentric therewith is a porous tube 133 of the circular cross section thus providing an annular chamber 134 between the shell 129 and the porous tube 133. An air inlet 135 provides a supply of pressurized air to the annular chamber 134 from an air manifold 137 (FIG. 1) via a flexible tube 139. The air under pressure flows through the porous tube 133 and assures that the fluid characteristics of the powder are not lost in the hose connector assembly 127. Any suitable porous material, for example, sintered metals, may be employed for the tube 133; however, the preferred material is porous Vyon plastic.

Accuracy is assured in the filling operation by curtailing the flow of particulate material as soon as the scale mechanism 37 indicates the proper weight of product has entered the bag. An air cylinder-actuated pinch valve 141 is provided at about the central portion of the flexible coupling 31, as is relatively standard in this packaging art. A housing 142 is secured to the lower support framework 35, and the spout assembly 29 is supported by insertion into the front side of the housing 142. The forward end of the flexible coupling 31 is connected to the rear side of the housing 142 by a hose connector assembly (not shown), which is generally similar to the hose connector assembly 127 and likewise contains an annular chamber, exterior ofa porous tube, into which fluidizing air is fed from the mainfold 137.

As seen in FIG. 3, the spout assembly 29 comprises an elongated outer tubular shell 145, the front end of which is cutoff at about a 30 angle and bent slightly downward. A supporting weldment 147 closely surrounds the spout shell 145 at a location near the rear end thereof and is suitably affixed thereto, as by welding. The weldment 147 contains an upstanding annular flange 149 by which the spout assembly 29 is bolted to the housing 142 which contains a cavity that receives the rearward portion of the spout assembly. Mounted concentrically within the shell 145 of the spout is a porous tube 151 of circular cross section and of appropriately smaller diameter than the shell in order to provide an annular chamber 153 therebetween. Air from the mainfold 137 is supplied via flexible hose 155 to an inlet 157 leading to the annular chamber 153. This air passes through the porous tube and assures that the particulate matter flowing through the spout assembly 29 remains fluidized throughout the entire length of travel therethrough.

When a valve bag is fitted over the spout 29 with its lower end resting in the cradle of the scale mechanism 37 and is being filled, the fluidizing air which enters the bag with the particulate matter primarily escapes from the bag in the region surrounding the spout assembly 29. To prevent very fine material which might be carried out of the bag with this escaping air from contaminating the general region of the bag-filling apparatus 11, a dust hood 159 is mounted on the housing 142 and disposed around the rearward end of the spout assembly. This hood 159 is connected with an exhaust system 161 which is maintained at a pressure slightly below atmospheric. If desired, an auxiliary cylinder (not shown) may be employed to clamp the valve bag to the spout.

In the operation of the bag-filling apparatus 11, the hopper assembly 13 constitutes an intermittently generally closed system as it is cut off from the atmosphere at the top by the butterfly valve assembly 15. The particulate material within the hopper assembly is maintained in fluidized condition by the air injected upward through the lower pad 47. Particulate material to replenish that which is filled into a bag is intermittently charged intothe hopper assembly 13 by opening the butterfly valve !5 for a timed period during the interval when the pinch valve 141 has closed and the valve bag which has been filled is being removed from the spout and replaced by an empty bag.

As previously indicated, uniform fluidization of particulate products which are considered especially difficult to handle is assured by the combination of the generally vertical upward injection of fluidizing air through the pad 147 in combination with the vibration of the hopper assembly 13 in a lineal direction. It is important that the vibration is applied in a lineal direction, as opposed to the application of generally circulatory vibration forces which would be created by normal eccentric-type vibrators, and the particular direction of lineal vibration has also been found to be important.

Any suitable linear vibrator 90 may be employed; however, the preferred vibrator is of the illustrated type, which is available on the market under the name Ajax Vibrating Shaker. As shown in FIG. 7, the illustrated vibrator 90 utilizes the forces set up by rotating two offset

weights

165 and 167 simultaneously in opposite directions. The weight 165 is keyed to the vibrator drive shaft 123, and the weight 167 is keyed to a stubshaft 169. Affixed to the ends of each of the

shafts

123 and 169 are integral helical gears 171 which drive the two shafts simultaneously. Bearings 173 are located near the outer ends of each shaft. The

weights

165 and 167 each include a collar portion 175 which fits over the respective shaft, and bearings 177 are disposed about the exterior surface of the collar portion 175. The weights, gears and bearings of the vibrator 90 are completely enclosed in an exterior housing 179 which is formed integrally with the base 103.

It should be understood that, at two points in each complete revolution of the weights I65, 167, the combined centrifugal forces of the two weights will be synchronized. These are the two points at which the weights pass each other, and these two points will be exactly 180 apart. Thus, rotation of the weights produces a straight line, oscillating force in the plane of the passing weights. Accordingly, the connection of the vibrator 90 to the hopper assembly 13, via the pair of cooperating

bracket assemblies

69, 71, causes this straight-line oscillating force to impart oscillating movement in a straight line to the hopper assembly, which is otherwise unrestrained because exterior connections to it are made via flexible couplings and because its ultimate support is through the four vibration isolators 67.

FIG. 7 shows the

weights

165, 167 of the vibrator 90 at points where they are directly opposed to each other and thus are exerting cancelling forces. This illustrated location is exactly 90 or halfway between the two points in each complete revolution wherein the centrifugal forces exerted will be synchronized. Thus, it can be seen that the orientation of the vibrator 90 relative to the hopper assembly 13 determines the angled at which the straight line oscillating movement, which is imparted to the hopper assembly 13, is oriented. The standard construction of the illustrated vibrator 90 is such that if the vibrator mounting bracket 91 is positioned so that the drive shaft 123 of the vibrator and the drive shaft of theelectric motor 113 both lie in a horizontal plane, the straight line oscillating forces generated will be in the horizontal plate.

As previously described, the plurality of holes 99 in the vibrator mounting bracket 91 permits the vibrator assembly 27 to be rotated so that the straight line oscillating movement produced will be at various angles to the horizontal. In the location illustrated in FIG. 1, the plane passing through the drive shafts of the motor 113 and vibrator is oriented at about 45 from the horizontal. Furthermore, it should be understood that the vibrator 90 itself is capable of internal adjustment so as to change the direction in which the straight line oscillating movement will occur relative to the mounting base 103 of the vibrator. It can be seen that disengagement of the helical gears 171 from each other and subsequent reengagement of these gears are with the weights at different angular locations with respect to each other will result in a change in the location of the two points, relative to the mounting base 103, at which the combined centrifugal forces of both weights are synchronized. Thus, the straight line oscillating movement imparted to the hopper 13 can be oriented as desired by either rotating the mounting bracket 91 relative to the bracket assembly 69, or by adjusting the weights internally of the vibrator, or by a combination of both.

In addition to the proper orientation of the straight line oscillating forces which are created, the point at which these forces are applied to the hopper assembly 13, longitudinally of the hopper and relative to the support point of the hopper assembly, has also been found to be important. Considering the length of the hopper assembly 13 as extending between the fluidizing pad 47 and the butterfly valve assembly 15, the hopper should be supported at a location above the midway point thereof. Preferably, the hopper assembly is supported at a location spaced below the 15 by a distance between about 25 to 45 percent of the length of the hopper assembly. Consideration is also taken of the diameter of the hopper 13 in determining the distance at which the location of the support is spaced above the lower end (the fluidizing pad 47) of the hopper. To assure that the straight line oscillating forces achieve the desired uniform fluidization of the particulate matter in the bottom portion of the hopper assembly 13, the distance of the plane of support above the lower end of the hopper should be between about two and four times the diameter of the hopper. Furthermore, the location of the vibrator assembly 27 should be generally adjacent, and preferably slightly below, the point at which the hopper assembly 13 is supported, which in the illustrated embodiment is the horizontal plane defined by the four vibration-isolators 67.

It has also been found that it may be best to change the orientation of the straight-line oscillating movement imparted to the hopper in order to assure the most effective uniform fluidization with different particulate materials that are being packaged. Generally, the orientation of the oscillating forces should be along a line at an angle between 35 and 55 to the horizontal. For the majority of materials, however, the most effective results are obtained when the angle of the oscillating movement with the horizontal is between about 40 and 50. Because the optimum angle of the oscillating movement relative to the horizontal is likely to be different when different materials are being packaged, the adjustability of the vibrator assembly 27, as previously discussed, provides a bag-filling apparatus with the flexibility to package a variety of different particulate materials.

During the normal filling cycle, the apparatus 11 is operated through a control panel (not shown) containing a start button which the operator actuates when the empty bag is in position on the spout assembly 29 ready to be filled. The pinch valve 141 is opened, and fluidizing air is fed from the manifold 137 to the spout assembly 29 and to the connectors at opposite ends of the flexible coupling 31. The particulate material in the hopper assembly 13 is maintained in a uniform fluidized condition by means of the upward injection of fluidized air through the porous pad 47, and bridging or other collection or buildup within the hopper 131 prevented by the straight line oscillating movement imparted to the hopper assembly by the vibrator 27.

The injection of air into the upper end of the hopper assembly through the upper air inlet 57 encourages the flow of the fluidized material out the bottom of the hopper through the outlet 125 in the sidewall. Depending upon the particular product being packaged, the air which is injected through the fluidizing pad 47 will usually be in the pressure range from about 2 p.s.i.g. to about 8 p.s.i.g. A slight pressure zone is sometimes created at the top of the hopper by injecting air through the upper air inlet 57 at a pressure slightly higher than the air injected through the pad 47. However, with certain particulate materials, the pressure of the upper air may be equal to or even slightly lower than that applied to the lower pad 47. The fluidizing air applied to the connector assembly 127 from the air manifold 137 is maintained at a pressure which is slightly greater than that inside of spout assembly 29 and which is equal to or less than that applied to the pad 47.

Throughout the filling operation, the fluidized particulate material flows uniformly and smoothly from the bottom of the hopper horizontally through to the spout assembly 29 and thence downward into a valve bag fitted thereon. When the scale mechanism 37 indicates that the desired amount of material has been filled into the bag, the control panel automatically causes the pinch valve 141 to be closed, and the supply of the higher pressure air to the upper air inlet 57 to be terminated. The air cylinder assembly 17 associated with the butterfly valve is then actuated and held open for a sufficient time to allow the desired amount of material to be charged into the hopper assembly 13. Upon closure of the butterfly valve 15, the apparatus 11 is ready to perfonn another filling cycle as soon as the operator has an empty bag in place on the spout 29.

The present invention provides a method for efficiently filling containers with particulate material that is otherwise considered difficult to package. The upward flow of fluidized air with the application to the hopper of oscillating forces directed along a line at a predetermined angle to the horizontal assures smooth and constant flow of fluidized particulate material horizontally outward through the spout assembly and, with the air of the auxiliary fluidizing air applied thereto, results in the uniform filling of the containers with a weighed amount to very close tolerances. The illustrated bag-filling apparatus 11 is considered to perform excellently in the filling of valve bags and is capable of handling a variety of difiicult to package particulate materials, such as finely divided pigments of varying character and moisture content, as a result of the adjustability that is built into the apparatus.

Although the invention has been described particularly with regard to the illustrated embodiment, it should be understood that various modifications may be made thereto by those having the ordinary skill in the art without departing from the spirit and the scope of the invention. Various of the features of the invention are set forth in the claims which follow.

lclaim:

1. Apparatus for filling containers with particulate material which apparatus comprises a vertically disposed hopper, an inlet valve disposed at the upper end of said hopper for regulating the downward flow of particulate material into said hopper, means disposed at the bottom of said hopper for injection of fluidizing air thereinto, outlet means in said hopper near the bottom thereof, means associated with said hopper at a location above the longitudinal center thereof for applying lineal vibration to said hopper, spout means, means for flexibly connecting said spout means to said outlet means, and

means for supporting said spout means separately from said hopper to isolate said spout means from the vibrations applied to said hopper.

2. Apparatus in accordance with claim 1 wherein said hopper has a generally horizontal bottom, wherein said outlet means is located i n the sidewall of said hopper means, and wherein said fluidizing air in ection means includes an flat porous member located at said hopper bottom which directs said fluidizing air generally vertically upward.

3. Apparatus in accordance with claim 1 wherein air inlet means is located near the upper end of said hopper for injecting air thereinto, wherein said outlet means is located in the sidewall of said hopper means, wherein said spout means is horizontal and includes an outer shell and an inner porous tubular member, and wherein means is provided for injecting low pressure fluidizing air radially into the central portion of said spout through said porous tubular member.

4. Apparatus in accordance with claim 1 wherein said hopper is supported at a location spaced downward from the inlet valve a distance between about 25 percent and 45 percent ofthe length of the hopper.

5. Apparatus in accordance with claim 4 wherein said lineal-vibration-applying means is located adjacent said location of support of the hopper.

6. Apparatus in accordance with claim 4 wherein said lineal-vibrating-applying means is located just below said support location for the hopper.

7. Apparatus in accordance with claim 6 wherein said hopper is circular in cross section and the distance between the lower end of said hopper and said location of vertical support is between about two and four times the diameter of the hopper.

8. Apparatus in accordance with claim 1 wherein said lineal-vibration-applying means imparts straight line oscillatory movement to said hopper along a line at an angle between 35 and 55 with the horizontal.

9. Apparatus in accordance with claim 1 wherein said lineal-vibration-applying means is adjustable relative to the horizontal so that the straight line oscillatory forces created can be oriented to the horizontal as desired.

10. Apparatus in accordance with claim 9 wherein said lineal-vibration-applying means is secured to a mounting bracket having a plurality of holes which can be selectively aligned with holes in a bracket assembly connected to said hopper whereby the vibrator bracket can be secured to said bracket assembly at various relative rotative orientations thereto.

11. A method for filling containers with particulate material by means of an apparatus including a vertically disposed hopper having a normally closed inlet valve disposed at its upper end, pad means disposed at the bottom of said hopper for injection of fluidizing air thereinto, and spout means connected to outlet means near the bottom of the hopper, which method comprises injecting fluidizing air upward into particulate material in the hopper through the pad means, injecting air into said spout means, injecting air into the upper end of said hopper, and applying lineal vibration to said vertical hopper which is supported at a location above the longitudinal center thereof, whereby said particulate material is uniformly conditioned and aerated to provide a product of consistent density and whereby bridging of said material or buildup of said material on the walls of said hopper are positively prevented.

12. A method in accordance with claim 11 wherein said lineal vibration is applied along a line at an angle between 35 and 55 with the horizontal.

13. A method in accordance with claim 11 wherein said air is injected into said upper end of said hopper at a pressure slightly above that of the air injected through said pad.

14. A method in accordance with claim 11 wherein said spout means is generally tubular in shape and fluidizing air is injected radially thereinto.

UNITED STATES PATENT OFFICE Patent No.

Dated April 27, 1971 Inventor(s) Thomas B. Sturges It is certified that error appears in the above-identified patent and that'said Letters Patent are hereby corrected as shown below:

line line Column Column 2, before "even" delete the letter "e" 27, "4! should be 4l-,

43, "hooper" should be hopper,

70, "78" should be --87.

20, "hear" should be --near-,

53, "mainfold" should be --manifold,

66, "mainfold" should be manifold.

19, "15" should be l5-,

72, "angled" should be angle.

35, before "15" insert butterfly valve assembly.

"air should be -aid.

Claim 2 "an" should be -a.

Signed and sealed this 21st day of December 1971.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. Attesting Officer ROBERT GOTTSCHALK Acting Commissionerof Patents

Claims

1. Apparatus for filling containers with particulate material which apparatus comprises a vertically disposed hopper, an inlet valve disposed at the upper end of said hopper for regulating the downward flow of particulate material into said hopper, means disposed at the bottom of said hopper for injection of fluidizing air thereinto, outlet means in said hopper near the bottom thereof, means associated with said hopper at a location above the longitudinal center thereof for applying lineal vibration to said hopper, spout means, means for flexibly connecting said spout means to said outlet means, and means for supporting said spout means separately from said hopper to isolate said spout means from the vibrations applied to said hopper.

2. Apparatus in accordance with claim 1 wherein said hopper has a generally horizontal bottom, wherein said outlet means is located in the sidewall of said hopper means, and wherein said fluidizing air injection means includes an flat porous member located at said hopper bottom which directs said fluidizing air generally vertically upward.

4. Apparatus in accordance with claim 1 wherein said hopper is supported at a location spaced downward from the inlet valve a distance between about 25 percent and 45 percent of the length of the hopper.

8. Apparatus in accordance with claim 1 wherein said lineal-vibration-applying means imparts straight line oscillatory movement to said hopper along a line at an angle between 35* and 55* with the horizontal.

12. A method in accordance with claim 11 wherein said lineal vibration is applied along a line at an angle between 35* and 55* with the horizontal.