US3574271A

US3574271A - Apparatus for sealing a valve opening

Info

Publication number: US3574271A
Application number: US810687A
Authority: US
Inventors: Nils Eric Andersson
Original assignee: Skogsagarnas Industri AB
Current assignee: Skogsagarnas Industri AB
Priority date: 1968-04-01
Filing date: 1969-03-26
Publication date: 1971-04-13
Anticipated expiration: 1988-04-13
Also published as: DE1914942A1; FR2005275A1

Abstract

A method and apparatus are provided for employing an adhesive into the valve opening of valve sacks in order to produce a sealing of the valve opening after the sack has been filled. The adhesive is injected into the valve through an opening in the sack communicating with the inside of the valve. The apparatus includes a punching member arranged to produce said opening and to deliver the adhesive in the desired amount.

Description

[56] References Cited UNITED STATES PATENTS 1,882,108 10/1932 Andreas 53/38 3,191,360 6/1965 Meissner et al. 53/383 Primary Examiner-Theron E. Condon Assistant Examiner-Horace M. Culver Attorney-Albert M. Parker Nils Eric Andersson Stromsnasbruk, Sweden [21] Appl. No. 810,687

Mar. 26, 1969 [45] Patented Apr. 13, 1971 Skogsagarnas lndustri Aktiebolag Stromsnasbruk, Sweden Apr. 1, 1968 Sweden 43 19/68 United States Patent [72] Inventor [22] Filed [73] Assignee [32] Priority ABSTRACT: A method and apparatus are provided foremploying an adhesive into the valve opening of valve sacks in order to produce a sealing of the valve opening after the sack 53/285, has been filled. The adhesive is injected into the valve through 53/383 an opening in the sack communicating with the inside of the B65b 7/02 valve. The apparatus includes a punching member arranged to 53/38, 285, produce said opening and to deliver the adhesive in the 383, 35, 393 desired amount.

[54] APPARATUS FOR SEALING A VALVE OPENING 7 Claims, 3 Drawing Figs.

[50] Field of Pmwm 13 nan SHEET 1 OF 2 Fig. 3

PATENTEU APR 1 3 197i sum 2 or 2 m, kmm

APPARATUS FOR SEALING A VALVE OPENING The present invention relates to a method of sealing valve openings in valve sacks by means of an adhesive compound, and apparatus therefor.

The object of the invention is in the first place to prevent such valve sacks being manually emptied by mistake, which is of particular importance in such cases when the contents contain poisonous or damaging substances, and to produce a moisturetight valve.

For this purpose it has previously been suggested to apply a suitable adhesive compound inside the valve or the contents of the sack. In this case the adhesive compound is introduced in the valve opening by injecting it through a nozzle insertable in the open end of the valve.

It has, however, been found that with such means having relatively long extrusion nozzles there is a risk of undesirable dripping of glue and the nozzles are difficult to clean.

It has now been found that the above-mentioned disadvantages can be completely eliminated by means of the present invention. Essentially characteristic of the new method is that the valve sack with the valve fitted on a filling tube is provided after completed filling with at least one opening communicating with the inside of the valve, after which the adhesive compound is introduced into the valve through the opening formed so that when the filling tube is removed the valve will be compressed and sealed by the pressure of the contents.

A suitable means for carrying out the suggested method consists substantially of a housing near the filling tube, said housing being arranged to be raised or lowered and comprising at least one punching member projecting from the lower side of the housing towards the filling tube and arranged to be inserted through a slot in a liplike extension of the filling tube to punch an opening communicating with the inside of the valve, the inside of the punching member being connectable to a means for introducing the adhesive compound inside the valve.

In this case each punching member suitably has an axial bore hole. The end of this hole facing away from the working surface of the punching member opens out to surround a stationary member, a space connectable to a compressed air source being provided around the stationary member and communicating with the bore hole. The stationary member includes a conduit for feeding adhesive to the bore hole, the adhesive flow being regulated by means of a needle valve.

In the following the invention will be described in more detail with reference to the accompanying drawings wherein:

FIG. 1 shows a schematical view of one embodiment of a means suitable for carrying out the method;

FIG. 2 a detailed transverse view, partly in section, of the means shown in FIG. 1; and

FIG. 3 a longitudinal section of the means of FIG. 1, showing another embodiment of the punching member.

One designates a valves sack which, by its valve 2 is fitted onto a filling tube 3 in known manner. The front end of the valve tube 3,-in a direction towards the valve sack, continues into an extended lip 4 which abuts the upper limiting surface of the valve 2. Above the filling tube 3 is a means 5 for applying the glue, this means comprising a housing 6 with a punching member 7 stationarily arranged on its lower side facing the filling tube 3, said punch having a longitudinal internal bore hole 8. The bore hole 8 of the punching member 7 expands at the end turned away from the filling tube 3 into an enlarged cavity into which a stationary member 9 projects for application of the adhesive compound, in such a way that a space 10 is formed around the member 9 by said enlargement. The space 10 is thus connected by means of conduits 11 provided with valves to a compressed air source, not shown in the drawing. The member 9 projecting into the enlargement is provided with an inner space 12 with a conical outlet 13, which is intended to cooperate with a needle valve 14 axially displaceable in the inner space 12, the needle valve having a rod 15 projecting from the upper side of the housing 6, which Each lifting member 18 comprises a spring-loaded piston 19 projecting from the lower side of the housing, the piston rod 20 projecting from the upper side of the housing 6 and being similarly firmly attached to the transverse rod 16.

In the lip 4 of the filling tube 3 facing the lower side of the housing 6 are a number of openings 21 corresponding to the number of punching members 7 and preferably havingsomewhat greater diameter than the diameter of the punching member 7.

The housing 6 can also be raised or lowered by means of two guiding rods 22, 23 and a cylinder 24.

In the embodiment shown in FIG. 2 the punching members 7 have an axial bore hole running through them. As seen in FIG. 3, the bore hole in the punching members 7 may be designed in such a way that the glue can be applied in the immediate vicinity of the punching. For this purpose the punching member is provided with a side opening 26 communicating with the inner bore hole, said opening being arranged at such an angle to the axial bore hole that the stream of glue is directed towards the inside of the valve, near the punching.

The means operates in the following manner:

When the sack has been filled the housing 6 is moved down towards the filling tube 3. The air supply is thus opened to the gaps 11 and the needle valves 14 sealingly abut the pointed extensions of the inner space 12. If the movement of the housing 6 is continued towards the filling tube 3 the punching members 7 will be inserted into corresponding openings 21 in the lip 4 of the filling tube 3 so that holes or openings are punched out in the valve wall and the front ends of the punching members 7 will be situated inside the valve 2. During the entire punching process a flow of air is maintained through the punching members. When the punching operation has been completed, therefore, the lower side of the housing 6 is in contact with the filling tube 3 supporting the sack valve, and the pistons 19 of the lifting members 18 are withdrawn into the housing 6, with the result that the transverse rod 16 is lifted and the needle valves 14 are also lifted from their sealing positions. Thus the adhesive compound in the inner spaces 12 is introduced into the bore holes 8 and, by means of the airflow, applied inside the valve 2. In the embodiment according to FIG. 2 a certain amount of glue is transferred to the inner surfaces of the valve 2 situated opposite the openings 21 and in the embodiment shown in FIG. 3 the glue is applied inside the valve at the same time as the holes are punched. As can be seen from the drawings, the punching members 7 are suitably designed in such a way that a hole is not punched completely out, but a flap 25 is punched which, upon the subsequent return stroke of the means, i.e. when the housing is returned to its original position, canat least partially spring back and thus at least partially close the opening. Upon the return stroke of the housing 6, the needle valves 14 are also returned to the sealing starting position since the pistons 19 are released and, due to their spring-loading, will return to their original positions projecting from the housing 6, which means that the transverse rod 16 is also returned to its original position.

The invention thus makes it possible to apply glue inside the valve without risk of dripping and at the same time easily check the glueing. The proposed method also facilitates adjustment of the various time intervals between punching, application of the glue and air supply, since these functions can easily be controlled by valve means situated on the housing.

The invention is, however, not limited to the embodiments shown in the drawings, but can be varied in many ways within the scope of the following claims.

It has been found particularly suitable to use the present invention for applying hot adhesive compounds since a completely water vapor tight sealing can be achieved, which is particularly suitable for materials sensitive to moisture.

Iclaim:

1. Apparatus for sealing a valve opening in a valve sack after the sack has been filled but while the valve is still fitted on a filling tube whereby upon withdrawal of the filling tube the pressure of the sack contents will compress and seal the valve, comprising; a filling tube having a liplike extension for insertion into the valve sack, a slot through the liplike extension, a housing adapted to be raised and lowered, at least one punching member projecting from a lower side of the housing and adapted to be inserted through said slot for punching an opening communicating with the interior of the valve and means within each punching member connectable to a supply of adhesive composition for introducing adhesive compound into the valve interior.

2. Apparatus according to claim 1 wherein each punching member is tubular and has a working end surface and an axial bore hole extending from said working end surface to an enlarged chamber, a stationary member for carrying adhesive compound being within said chamber, and chamber space around said stationary member being connectable with a source of compressed air for forcing adhesive out through said bore hole; and a needle valve being within said stationary member for regulating flow of adhesive from a space inside the stationary member to the bore hole.

3. Apparatus according to claim 2 in which said working end surface of the punching member is obliquely aligned for punching a flap out of a valve sack.

4. Apparatus according to claim 2 wherein the punching member has a side opening communicating with said bore hole through a passage disposed at an angle to the horizontal.

5. The apparatus of claim 2 in which the needle valve is axially displaceably journaled in the housing by means of a rod, the end of said rod projecting from an upper side of the housing being firmly connected to a transverse rod.

6. The apparatus of claim 5 including lifting means cooperating with said needle valve, said lifting means including a spring loaded piston projecting from the lower side of the housing, means coupling said piston to said transverse rod for opening said needle valve when the punching member is inserted into said valve to inject adhesive through a hole punched by the punching member.

7. Apparatus according to claim 6 including three punching members, said lifting means including two piston assemblies coupled to said transverse rod.