US2235394A

US2235394A - Means for vacuum sealing packages

Info

Publication number: US2235394A
Application number: US283794A
Authority: US
Inventors: Samuel H Berch
Original assignee: Individual
Current assignee: Individual
Priority date: 1939-07-11
Filing date: 1939-07-11
Publication date: 1941-03-18
Anticipated expiration: 1958-03-18

Description

March 1s, 1941. s H BERCH 2235394' MEANS FOR VACUUM SEALING PACKAGES Fiigd July 11, 1939 Eigf 25 .a2 3/ ZF Patented Marr-18, .1941

l*UNITED STATES PATENT OFFICE vSamuel H. Bei-ch, Beverly Hills, Calif. Application July 11, 1939, Serial No. 283,794

6 Claims.

This invention relates to packaging machinery and particularly pertains to means for vacuum sealing packages and isa continuation in part of my application entitled Method and means of packaging and vacuum sealing products," filed June 13, 1939, Serial No. 279,150.

In the packaging of various products within a bag-like container capable of maintaining a vacuum seal, as shown in my application of which this is a continuation in part, it is necessary to flll the container and thereafter exert suction action upon the container and its contents prior to forming a tight and permanent seal across the mouth of the lled container. When the product to be sealed within the container is finely divided material, such for example as ground coiee, considerable diillculty has been experienced in forming a tight seal and seam across the mouth of the bag since there is a tendency for the finely divided material to be drawn upwardly into the mouth of the bag by suction. An undesirable amount of this material may be trapped in the seam which-is being formed. This causes an imperfect scam to be made and will prevent the package from being permanently vacuum sealed. It is the principal object of the present invention, therefore, to provide means whereby a flexible container may be filled with a finely divided product, thereafter subjected to vacuum action and then sealing the mouth of the container while holding the same in a manner to prevent the seepage of the granular product into the seam as it is being formed and sealed, whereby the package will be permanently vacuum sealed in an automatic mechanical operation.

The present invention contemplates the provision of a mold designed to receive a package to be vacuum sealed and over which mold a vac- 0 uum head is applied to exert a suitable suction action on the package and its contents, the structure including means for folding the mouth of the container and holding the mouth snfilciently tight to prevent nely divided material from being drawn between the abutting faces of the held portion while sealingthe same.

The invention is illustratedby way of example in the laccompanying drawing, in which:

Figure 1 is a view in vertical lsection and elevation showing :a package mold, the vacuum the present invention Ais particularly concerned.

Fi'g.2 is an enlarged vfragmentary view showing the details of construction of `,the seaxning means. f

I of non-stretching material I4 and an inner sheet head therefor and the seaming means of 'which Fig. 3 is a view drawn on a reduced scale and indicating the manner in which the folding and seaming means is operated.

`Fig. 4 is a fragmentary view indicating lfolding iingers adapted to form conugations in the seam. 5'

Referring more particularly to the drawing, I0 indicates a mold within which a package II is placed. The package Il is formed with side walls I2 land I3 which may comprise an outer sheet l0 of stretching material I 5. Such a structure is shown in my issued PatentNo. 2,102,716. The inner sheet of stretchable material is preferably a rubber compound, such for example as Pliofilm. 'This material has the characteristic of being capable of heat sealing. The horizontal section of the mold` I0 is substantially rectangular and the depth of the mold is such as to provide an upper length of the side walls I2 and I3 which extends above the level to which the package i`s lled. I'his mouth portion is indicated at I6 in the drawing. Mounted around the mouth of the mold I0 is a pan I'I which has a horizontal wall' portion and a marginal flange which extends upwardly and is fitted with a lip I8 at its upper edge. A movable vacuum head I9 is provided to be positioned over the `mouth of the pan I1 and to form a hermetical seal 'therewith. A suitable gasket I9' rests upon the lip I8 to provide this seal. A suction pipe 20 is-30 carried by the' head and communicates with the space in the mold through suction ducts .2L Mounted within the pan Il and above the mold I0 are folding

fingers

22 and 23. These ngers swing vertically and' are carried upon pivot pins .2l and 25. Normally the folding ngers 22 and 23vstand vertically, -as indicated in Fig. 3 of the drawing, and swing downwardly `to their 'horizontally aligned .position as shown `in Figs. 1 and `2. The pins '24 and 25 of the ngers carry gear :segments 2S and 21 which are in mesh with each other Aand insure 'that the folding .lingers 'will move in imlson Vin .their operation. Une -of the Apins :is fitted with trip fingers i128 :and 29 which may yengage operating structures not :shown in the drawing but by which the :gear segments '26 :and 521 .may be rotated in `alternate i directions.

In `my previously :filed =application the folding ngers 122 and '.23 were .indicated as -being of ,50 metal. 'It was .found :in 'operation that when Vso constructed -the .faces vof 'the Aportion 'I6 of the ypackage could vnot be held in sumciently close commet fto A.prevent the lmaterial vwithin the Apackage from being upwardly into the 55 seam when subjected to suction action. In the present instance the fingers have been constructed in a manner to insure that the meeting edges of the package will not tend to slip and loosen when subjected to suction action, and

that furthermore these edges will be held with sumcient force to prevent granular material from seeping into the seam to be formed while allowing the suction action to evacuate the container and permit it to then be sealed.

'I'he construction of the folding fingers is particularly shown in Fig. 2 of the drawing. Here it will be seen that the finger 23 has a flat bottom face 33 which folds down upon the wall section I3 for a distance substantially one-half Aof the width of the package. The free end of the finger 23 is substantially square, as indicated at 3|, and when in its folding position stands vertically. A relatively thin tongue or blade 32 is formed as a part of the finger adjacent the free end. This tongue has an upper face 33 substantially parallel to the lower face 3|I.'4 Anl obliquely disposed sealing face 34 is formed on the back of the finger 23. 'I'he folding finger 22 has a face 35 which extends fora distance substantially halfway the width of the package II, and when the

ngers

22 and 23 are in their folding positions the

faces

35 and 33, respectively, of these fingers will lie in a common horizontal plane. At the free end of the folding finger 23 there is a blade 36 which overhangs the blade portion 32 of the nger23. A shoulder 31 is formed on the folding finger 22 beneath the blade and in the folded positions of the fingers stands parallel to the end face 3| of the finger 23. `At this particular time these faces are spaced apart substantially the distance represented by the thickness of the Wall sections I2 and I3 which are, collapsed against each other to form the mouth portion I6. The blade portion 36 has a face 33 which is parallel to the face 35 and overhangs the blade 32. 'I'he spacing between the contiguous faces of the

blades

32 and 36 is such as to insure that the mouth of the container will be fully. collapsed and held in this position sufliciently tight to prevent large grains of nely divided material from the package to be drawn up into the seam to be formed at the mouth of the container. Overhanging the blade portion 36 of the folding finger 22 is a rubber blade 39 which is suitablysecured to the folding finger 22, such as by the screw 40. lThe lower face 4I of the rubber blade 39 lies in substantially the same plane as the face 33 of the blade portion 36. Thus, when the finger 22 is down in its folded position it will compress the mouth portion of the package against the blade 32 of the folding finger 23. The rubber blade 39 will act to hold the abutting faces of the mouth portion I6 ofthe package rmlyso that small particles of powder flneness will not be drawn into the seam, while permitting suction action to take place through the seam. It is also to be pointed out that vthe rubber blade 39 will yieldably press against the walls forming the mouth portion I6 of the package so that a uniform pressure will be exerted against these walls irrespective of minute irregularities which may occur in the thickness of the sheets of material.

It is also to be pointed out that in view of the 'fact that the rubber blade 39 will frictionally engage the walls of the mouth of the package there will not be an opportunity for the wall portions to slip with relation to Aeach other. If the wall portions do tend to slip while the seam is being formed the seam will pucker and a vacuum-tight seal will not be provided. The use ment 43 is incorporated within the heat sealing member 4| As shown in Fig. 1, the heat sealing element is mounted on'a stud 44 carried in a boss 45 of a supporting lever 46. This lever in turn is pivotally mounted within a bearing 41 upon a pin 43. The bearing 41 is carried as a part of the vacuum head I9. Suitable supporting means are provided for the free end of the lever 46 and comprises a nger 53 mounted upon a rock shaft 5I. This is operated by suitable mechanism with which the present invention is not concerned.

In operation of the present invention the package I| is placedwithin the mold I with the portion I6 extending upwardly above the top of the mold and within the pan I1. The

folding fingers

22 and 23 are properly adjusted upon the

pins

24 and 23 so that as' the gears 26 and 21 -rotate in unison the finger 23 will fold down first with the finger 22 in overlapping relation thereto. As these fingers fold downwardly to the position shown in Fig. 2 of the drawing the side walls I2 and I3 of the package will be folded toward each other at the upper end of the `package and the mouth portions I6 will be closed.

As the finger 22 folds over the finger23 the mouth portion I6 will be folded down upon the face 33 of the blade portion 32 of the folding finger 23 and then at an inclination. along the face 34. Ihis mouth portion will be held down by the overlapping folding nger 22 since its metal face 33 will fold down over the material and exert pressure against the seam portion I3 to exclude granularmaterial from the seam. At

the same time the rubber b1ade39 will fold downagainst the portion I6 of the package and will yieldably hold that portion against the face 33 of the folding finger 23. When suction action Iis then exerted upon the package through the pipe 2li and the ducts 2| the 4air will be exhausted from the package but the material therein will be entrapped. It is to be understood that the face of 'the rubber blade 39 may be of any desired texture. That is to say, it may be' smooth, corrugated, or otherwise roughened without departing from the spirit of the invention.

After the package has been acted upon by the two

folding fingers

22 and 23 to hold the mouth I6 of the package in a clamped position the heating element 4I is lowered against the outer length of the portion I6 of the package. Heat and pressure will thus be supplied in a suflicient degree to cause the Pliolm forming the inner liner I to be heat-sealed along its abutting faces. Thus, the contents of the package will be subjected to a vacuum action, after which the mouth portion of the package will be thoroughly heatsealed without any possibility for extraneous matter from the package to be drawn into theseal and to make an imperfect seam.

It will thus be seen that the structure here disclosed provides simple and effective means whereby a flexible container may be vacuum sealed and extraneous matter will be excluded from the seam, therebyinsuring that a tight seam and a permanent seal are readily effected.

While I have shown the preferred form of my invention as now known to me, it will be understood that various changes may be madein combination, construction, and arrangement of parts by those skilled in the art, without departing from the spirit of my invention as claimed.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. In a package sealing machine, a mold into which a flexible filled package is placed, the mouth of the package being sealed by forminga straight seam entirely across the top of the package with the inner abutting faces sealed together,

a pair of folding fingers carried by the mold at opposite sides of the package, means for folding said fingers down against the side walls of the package whereby the side walls of the package will be folded together along substantially the median line of the package and whereby the side walls will be held in their folded position, and sealing means acting along said abutting seam to cause the abutting faces to cohere.

2. Same as 1, adding the following: said folding fingers operating in sequence whereby their free ends will overlap in holding the Walls of the mouth of the package together.

3.' In a package sealing machine, a mold into which a flexible filled package is placed, the mouth of the 'package being sealed by forming a straight seam entirely across the top of the package with the inner abutting faces sealed together, a pair of folding fingers carried by the mold at opposite sides of the package, means for folding said fingers down against the side walls of the package whereby the side walls of the package will be folded together along substantially the means acting along said abutting seam to causev the abutting faces to cohere, said folding fingers operating in sequence whereby their free ends will overlap in holding the walls of the mouth of the package together, and yieldable means on the free ends of the said fingers for exerting a yieldable pressure against the folded Walls of the package. l

4. Same as 3, adding the following: said yieldable means being in the form of a rubber pressure member.

5. In a package sealing machine, a mold structure within which a package may be sealed under vacuum, a pair of folding fingers mounted upon opposite sides of the mouth of the package by which the opposite side Walls of the package may be folded in against each other along the median line of the package and throughout the length of the mouth of the package, rubber elements carried on the free ends of said ngers to exert a yielding force against the opposite sides of the folded mouth ofthe package, and sealing means acting against the folded mouth of the package when thus held to seal the same under vacuum.

6. Same as 5, adding the following: said mold being provided with a conduit to communicate with suction exerting means acting to subject the package and its contents to suction while the mouth of the package is held closed and prior to the action of the sealing means.

SAMUEL H. BERCH.