US2531743A

US2531743A - Method of filling flexible containers with finely divided materials and machine therefor

Info

Publication number: US2531743A
Application number: US616298A
Authority: US
Inventors: Ray Don
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-09-14
Filing date: 1945-09-14
Publication date: 1950-11-28
Anticipated expiration: 1967-11-28

Description

Nov. 28, 1950 Filed Sept. 14, 1945 RAY METHOD OF FILLING FLEXIBLE CONTAINERS WITH FINELY DIVIDED MATERIALS AND MACHINE THEREFOR 2 Sheets-Sheet 1 .j pt; .6

Don Ray INVENTOR.

ATTORNEY Nov. 28, 1950 D. RAY 2,531,743

METHOD OF FILLING FLEXIBLE CONTAINERS WITH FINELY DIVIDED MATERIALS AND MACHINE THEREFOR 2 Sheets-Sheet 2 Filed Sept. 14, 1945 H/////////zV/A VA Don Ray I INVENTOR.

BY w Arrow Patented Nov. 28,1950

UNITED STATES PATENT OFFICE METHOD OF FILLING FLEXIBLE CONTAIN- ERS WITH FINELY DIVIDED MATERIALS AND MACHINE THEREFOR Don Ray, Beverly Hills, Calif.

Application September 14, 1945, Serial No. 616,298

9 Claims. 1

This invention relates to improvements in the art of packaging finely divided materials and particularly pulverulent materials such as, for example, powdered milk, chocolate, cocoa, prepared flours, lampblack, cornstarch, powdered sugar, finely ground pharmaceuticals such as powdered licorice, etc. The invention relates to a method of procedure whereby predetermined quantities of such finely divided materials may be placed into containers in a rapid manner without the creation of unpleasant and sometimes dangerous dusts. The invention also relates to a simple and effective mechanism whereby such finely divided materials may be placed into containers.

Lampblack, powdered milk and other very finely divided materials are packaged with difilculty because of the tremendous quantities of air adsorbed by each of the particles and contained between the particles. The movement of any volume of such finely divided material creates a cloud of dust. As a result, the operation is disagreeable to the operators and often gives rise to high losses and to dangerous dust problems since many of these dusts are of an explosive character. In addition, many of these finely divided materials are light in weight and very bulky. When placed into flexible bags, the volumetric capacity of the bag is not utilized to best advantage. A resort has been made to vibration of the package or container during the filling operation in an attempt to pack the pulverulent material into a smaller volume but such methods have not been satisfactory and in most instances aggravate losses and the formation of dusts.

The present invention employs a novel mode of operation which, generally stated, comprises supporting an open container within a chamber, reducing the pressure within and around the container simultaneously to a subatmospheric pressure, then isolating the interior oi. the container from the rest of the chamber, admitting the finely divided material into the container while such interior is isolated from the rest of the chamber, and eventually restoring pressure within the chamber to atmospheric and placing the filled container in communication with such chamber. In this manner the pulverulent or finely divided material may be admitted to a container which is under vacuum so that the vacuum within the container draws a desired amount of the material into the container. By conducting the operation in the manner stated, flexible or collapsible bags may be employed. The finely divided material does not come in contact with the atmosphere until the container has been filled. Definite pressure is utilized (in certain forms of the invention) for moving the material into the container and in compressing or compacting the material within the container.

The invention, as previously stated, is also directed to a simple and eflicient apparatus by means of which the packaging operation may be readily carried out.

It is an object of the present invention, therefore, to provide an improved method of packaging finely divided material without the creation of dusts and accompanying losses.

A further object of the invention is to provide a method of packaging by means of which flexible bags and other containers may be filledl under vacuum or at a subatmospheric pressure.

A still further object of the invention is to permit the packaging of finely divided pulverulent material in containers provided with heat and pressure-sensitive inner surfaces so that the filled containers may be rapidly and efiiciently sealed, the. method preventing the adherence of finely divided materials to the sealed areas of the bag, such dust or particles ordinarily rendering such areas ineffective in subsequent sealing operations.

Again, an object of the invention is to provide a novel combination of elements whereby finely divided materials may be easily packaged.

A still further object of the invention is to provide a packaging machine capable of handling finely divided materials.

These and other objects will become apparent to those skilled in the art from the following description. In order to facilitate understanding,

an exemplary form of apparatus is shown on the appended drawings.

In such drawings:

Fig. 1 is a side elevation of one form of device.

Fig. 2 is an enlarged vertical section through the housing of the device with actuating mechanism in elevation.

Fig. 3 is a horizontal section along the plane III-III of Fig. 2.

Fig. 4 is a horizontal section along plane IV--IV of Fi 2.

Fig. 5 is a vertical section along the plane V-V of Fi 2.

Fig. 6 is a horizontal section along plane VIVI of Fig. 2.

The simple form of device shown in these drawings comprises a housing I which may have transparent front and

rear walls

2 and 3, in order to permit observation of the packaging operation. The housing is preferably provided with an open bottom (a. bottom port being indicated at 4),

such bottom being capable of cooperating with a suitable movable closure including means for supporting a container with access of air therearound.

The movable closure may take the form illustrated and comprise a closure plate 5 capable of firmly seating around the open bottom of the housing I to form a. virtually gas-tight seal therewith. The closure plate may be provided with a recess portion or depression portion 6 adapted to loosely receive the container 7 to be filled. The inner walls of the recess portion may be provided with a plurality of ridges for the purpose of admitting air around the entire container I, such ridges being indicated in Fig. 6 at 8 and 9. Suitable gasketing means may be carried either by the closure plate 5 or the bottom of the housing i so as to make certain that a, virtually gastight seal is attained when the closure is brought into contact with the bottom of the housing. Any suitable means may be used in moving the closure into operative relation with the housing. Such means may comprise a suitably controlled, vertically movable lifter ill (shown in Figs. 1 and 5). Such lifter also function to properly center and guide the upper portion of the container i into operative relation with the mechanism within the housing.

The top ll of the housing carries a feeding tube H which extends downwardly into the housing. The upper end of this tube i2 is connected in any suitable manner to a supply of finely divided or pulverulent material which it is desired to package. In Fig. l the feeding tube is shown connected to the bottom of a hopper it,

the connection being made by means of a hop-- per block it.

As best shown in Figs. 2 and 5, the lower end oi the feeder tube i2 is provided with a form block the form block being adapted to loosely fit into the upper part of the container to be filled. in the form shown, the form block is provided with concave and convex container-contacting surfaces iii and it, such surfaces presenting a perimeter equal to the perimeter of the internal surface of the opening into the container i. It may be assumed for purposes of example, that the container '11 is a flexible, foldable bag made of paper, fibrous material, sheet nylon, paper coated with a thermoplastic coating, thin metal Y foil, cellophane, or various laminates. It may aiso be noted that the upper portion of the bag l extends above the supporting plate 5 so that when such plate is brought into seating engagement with the bottom of the housing the upper portion of the bag encircles the form block 65. Lower edges of the form block may be tapered as indicated at i5 in order to facilitate entry of the form block into the bag.

The feeding tube i2 is provided with an obturator by means of which the flow of material through the feeder tube may be controlled. Preferably such valve is located in the form block 95 and may take theform of a small shut-off valve ili mounted upon a rotatable pin or shaft l8 extending through the form. block, the valve being movable in a recess i9 formed in the lower face of the form block.

The valve i! may be actuated by means of a lever carried by the post Hi, the lever 20 being pivotally connected as by link 2| with an arm 22 mounted upon a valve-actuating shaft 23 extending upwardly through the top of the housing, the upper end of such valve-actuating shaft being provided with the operating handle 24.

The feeder tube [2 may carry sleeve 25 supporting a spider 26, the spider having radially extending lugs such as 21 adapted to pivotally support clamping

arms

28, 29, and the like. The lower ends of such arms are preferably provided with yieldable pads 3|, 32, etc., adapted to clamp the upper portion of the bag I against the form block IS. The pads 3|, 32 and the like preferably conform to the concave portions of the outer surface of the form block.

The upper end of each of the

clamp arms

23, 29, 30, is provided with an upstanding cam-contacting

finger

34, 35, 36, etc., such fingers being yieldably urged together or toward the feeder tube l2 by means of a continuous coiled spring or O ring 31 positioned within suitable notches or recesses formed in the outer surfaces of such fingers. In order to limit the inward movement of these fingers, a stop collar 38 may be carried by an upward extension of the spider 26.

Slidably mounted upon the tube I2 is a cam block 40 provided with a conical external face against which the ends of the

fingers

34, 35, may rest. Upward movement of the cam block is resisted by means of a cam stop nut 4| adjustably positioned upon the feeder tube. The cam block 40 is normally urged against the stop nut 4| by means of a spring 42 bearing against the spider 26 and upwardly against the cam block. As best shown in Fig. 5, the spring 42 may be partly retained within a recess formed in the lower portion of the cam block.

It will be evident from the description given that downward movement of the cam block will cause the

fingers

34, 35 and 36 to move outwardly along the conical face of the cam block, thereby pivoting the

clamp arms

28, 29 and 30 and bringing the pads 3|, 32 and the like in pressure contact against the upper portions of a container extending between the pads and the form block.

Downward motion of the cam block 40 may be imparted in any desired controllable manner. In the example given an operating handle 43 is shown pivoted upon a stud bolt 44 fastened in the side of the housing. The lower end of the operating handle i3 is provided with a cam 45' adapted to bear upon a lever 46 carried by a shaft 41, the shaft 41 being provided with a pair of cam-actuating arms t8 and 49 adapted to contact the upper portion of the cam block 40 and move the cam block downwardly.

The housing is also provided with means for controllablv connecting the housing with a source of suction. Such means may comprise a suitable port and a conduit 50 connected thereto. The conduit may include a three-way valve 5| by means of which the conduit may be selectively connected either with a source of suction or with the atmosphere.

The apparatus described hereinabove may be utilized in performing the method of this invention as follows:

A suitable container (such as the bag 'I) is placed within the recess 6 of the supporting plate 5 and moved against the bottom of the housing i so as to form a tight seal therewith. The upper portion of the bag 1 will be guided by the tapers l5 around the form blocks.

It will be understood that bags of different length but of the same cross-sectional size may be used, a suitable filler block being then inserted into the bottom of the recess 6 so as to make certain that a proper length of bag extends 5 above the plate i and between the form block and the clamping pads 3|, 32 and the like.

As soon as the supporting plate 5 is brought into contact with the bottom of the chamber I, valve ll may be turned to place the chamber in communication with a source of suction, thereby reducing the pressure within and around the container I to a desired uniform subatmospheric pressure. The entire interior of the housing will be reduced to such subatmospheric pressure; but it is important that both the interior and the exterior of the bag I be subjected to such low pressure. The indentations or concave surfaces of the filler block I5 assure communication between the interior of the bag and the atmosphere externally ofthe bag within the housing.

After the desired vacuum has been thus created, both within and without the bag, the interior of the bag is isolated from the rest of the chamber by actuating the handle 43, thereby causing cam block 40 to move downwardly against spring 42 to firmly clamp the upper portions of the bag 1 against the form block. When the bag is caused to cling to the concave portions I6 of the form block, other wall areas of the bag will be stretched taut against the convex portions IQ" of the form block.

Finely divided material may then be admitted into the bag I by opening the valve II. This valve is opened by means of actuating handle 24, valve actuating shaft 23, arm 22, link 2|, arm and valve post l8. Finely divided or pulverulent material will thus be admitted through the feeder tube l2 directly into the bag I. Since a subatmospheric pressure exists within the bag I, the finely divided material will move downwardly through the filler tube l2 and completely fill the bag, that is, fill the bag up to the level of the form block.

At this point it may be noted that the supply hopper l3 may be open to the atmosphere so that the supply of finely divided material in such hopper is subjected to atmospheric pressure at the top. It may be stated, therefore, that the differential in pressure between the hopper l3 and the interior of bag 1 facilitates filling of the bag.

In some instances it may be highly desirable to partly deaerate the finely divided material before it is admitted into the bag I. The hopper ll may be supplied with finely divided material from still another hopper through a suitable valved outlet and the hopper [3 may be connected with a source of suction sufficient to partly deaerate the finely divided material in the hopper I3 and to create an absolute pressure in such hopper slightly higher than that in the bag immediately prior to the filling operation.

Moreover, when materials capable of bridging are being packed, a stirring rod or a shaft provided with stirring arms or even an auger may be rotatably mounted axially of the feeder tube l2 so as to facilitate the movement of material through the feeder tube, such stirring rod or auger being preferably only driven when the valve l1 is open.

After the bag has been filled in the manner described above, pressure within the chamber is restored to normal by adjusting the valve 5| so as to place the chamber in communication with the atmosphere. In most instances it will be found that such air pressure acting upon the outside of bag I will compact the material therein to placed in communication with the atmosphere, the

clamp arms

28, 28, 30 are released (as by returning the operating handle 43 to its normal position), thereby permitting atmospheric pressure to act upon the surface of the finely divided material within the bag 1. The filled bag may then be removed from the chamber by permitting the closure plate 5 to drop, whereupon the bag may be immediately subjected to a sealing operation while still supported by the closure member 5, or it may be withdrawn from the closure member and subjected to the action of a separate sealing apparatus.

It may be noted that insasmuch as the bottom of the form block I5 is substantially in the same plane as the bottom of the chamber I, the finely divided material will be found to have filled the bag substantially to the level of the upper surface of closure member 5, as indicated by the line 52. Moreover, in the event the bag I is provided with a thermosealing inner surface or layer, the upstanding upper portion of the bag may be readily folded and sealed so that the contents are not subjected to the action of air for any appreciable length of time.

It has been repeatedly found that it is virtually impossible to obtain a hermetic seal to the open end of a bag if there is any dust on the sealing surfaces of the bag. The minute dust particles appear to keep the two surfaces from complete contact and instead set up channels between the surfaces through which air may readily pass. Bags filled in accordance with the present invention, however, have dust-free surfaces since the sealing surfaces of the bag are in contact with the form block i5 during the entire filling operation and that is the only time during which any dust may exist within the apparatus or within the bag.

It will be quite evident to those skilled in the art that the various operations may be carried out in an automatic sequential manner. The movement of the closure member 5 into contact with the bottom of the housing I may automatically cause valve 5| to place the chamber into communication with a source of suction and after a predetermined vacuum has been created within the bag, vacuum-actuated cylinders may cause the clamping arms to operate and the feeding valve I! to open in proper sequence. Electromagnetic or hydraulic means may also be utilized in carrying out the various operations in their proper order. The entire chamber may be purged with nitrogen or other inert gas; the feeding hopper l3 may also be purged with a similar inert gas in the event the product being handled is readily oxidizable and benefits from pretreatment with nitrogen or some other gas.

Although specific reference has been made to the filling of a flexible, collapsible bag in the example, it is to be understood that the method may be employed in packaging finely divided materials not only in bags but in various other containers such as cylindrical cartons, rectangular cartons with circular openings, etc.

These and other changes and modifications are contemplated and are embraced by the appended claims.

I claim:

1. A machine for filling containers with finely divided materials comprising: a housing having an open bottom; a removable closure for the bottom of the housing, said closure including means for supporting a container with access of air some extent. After the chamber has been thus therearound; a feeding tube positioned in the house and extending through the top thereof; a form block carried by the lower end of the feeding tube, the form block being adapted to loosely fit the upper part of a container to be filled; resilient clamping elements within the housing controllably movable to clamp the upper edge areas of a container to the form block; an obturatin member for the feeding tube; and means for controllably connecting the housing with a source of suction.

2. In a machine for filling containers with finely divided materials, the combination of: a housing having an open bottom; a removable closure for the bottom of the housing, said closme including means for supporting a container to be filled; a feeding tube positioned in the housing and extending through the top thereof; a form block carried by the lower end of the feeding tube, the form block being adapted to loosely fit the upper part of a container to be filled; resilient clamping elements controllably movable to clamp the upper edge areas of a container to the form block; an obturating member for the feeding tube; and means for con troilably connecting the housing with a source of suction.

3. In an apparatus of the character stated in claim 2, said form block being provided with concave and convex container-contacting sur faces substantially parallel to the walls of the container and presenting a perimeter equal to the perimeter of the internal surface of the opening into the container.

4. In a filling machine, the combination of: a filling conduit associated with a supply of finely divided material, a form blocl; carried by the end of the filling conduit, said form bloc being insertable into the opening of a container, said form block being provided with alternate concave and convex container-contacting surfaces substantially parallel to the walls of a container and presentin a perimeter equal to the perimeter of the internal surface of the opening into the container, movable valve means for controllably owning and closing the end of said conduit, and clamping means adapted to releasably hold the container against said form block.

5. A machine for filling containers with finely divided materials comprising: a housing, a removable closure for said housing, said closure including means for supporting a container, a feeding conduit positioned in the housing, a form block carried by the lower end of the feeding conduit, the form block being adapted to loosely fit the upper part of a container to be filled, clamping means adapted to releasably and resiliently hold the container against said form block, and a single means for controllably connecting the housing with a source oi suction to generate a uniform sub-atmospheric pressure within the housing and container supported therein before said clamping means resiliently press the upper areas of the container against the form block.

6. In an apparatus of the character stated in dill claim 5, the provision of a movable valve for controllably opening and closing the end of the feeding conduit.

7. A method of filling flexible containers with finely divided material comprising: supporting an open flexible container within a chamber; reducing the pressure within and around the container simultaneously to a substantially uniform, predetermined, sub-atmospheric pressure engaging external portions of walls of the container below the open end thereof and pressing opposed engaged portions of said walls inwardly toward each other to isolate the interior of the container from the rest of the chamber; admitting finely divided material into the container while the interior of the container is isolated from the res of the chamber; then restoring pressure within the chamber to atmospheric and placing thl filled container in communication with thr chamber.

8. In a filling machine, the combination of 1 a, filling conduit associated with a supply of finely divided material; a form block carried by the end of the filling conduit, said form block being insertable into the opening of a container, said form block being provided with parallel outer walls including alternate concave and convex container-contacting surfaces presenting a perimeter equal to the perimeter of the internal surface of the opening into the container; and movable valve means for controllably opening and closing the end of said conduit.

9. A method or filling flexible containers with finely divided material comprising: supporting an open fiexible container within a chamber; holding the flexible container in open position while maintaining communication between the chamber and the interior of the container; reducing the pressure within and around the container simultaneously to a substantially uniform, predetermined, sub-atmospheric pressure, engaging external portions of walls of the container below the open end thereof and pressing the engaged portions of opposed walls inwardly toward each other into concave configuration to isolate the interior of the container from the rest of the chamber; admittin finely divided material into the container while the interior of the container is isolated from the rest of the chamber; then restoring pressure within the chamber to atmospheric and placing the filled container in communication with the chamber.

DON RAY.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,013,381 Dunn Jan. 2, 1912 1,993,442 Greven Mar. 5, 1935 2,302,693 Hoar Nov. 24, 1942 2,428,598 Weaver Oct. 7, 1947