EP0198552B1

EP0198552B1 - Equipment for producing conical products

Info

Publication number: EP0198552B1
Application number: EP86200615A
Authority: EP
Inventors: Robert Maria Jozef Hubert Eurlings
Original assignee: Bates Cepro BV
Current assignee: Bates Cepro BV
Priority date: 1985-04-11
Filing date: 1986-04-11
Publication date: 1988-11-17
Also published as: NL8501068A; EP0198552A1; DE3661175D1

Description

The invention relates to an apparatus for manufacturing conical objects, such as valves for package bags, from two webs of flexible material supplied from respective rolls.
A valve is a tubular device made of flexible material, through which a bag of flexible material can be filled and which can close the opening in the bag after that. For filling, the valve is slid about a filling pipe and in such a manner that the opening of the filling pipe extends through the inner end of the valve into the bag.
Usually the shape of the valve is cylindrical, if slid about the filling pipe. During production and transport of the empty bag the valve is folded flat and thus has a rectangular shape.
A conical valve is not cylindrical, but has the shape of the surface of a flattened cone. During production and transport of the empty bag the valve is folded flat and has the shape of a trapezium.
The valve has two functions:

-to enclose the filling pipe as thoroughly as possible during filling and
-to transform it in such a manner after filling that the filling goods are prevented from passing through to outside.

The conical valve is far more satisfactory in both functions than the cylindrical valve known up to now. There are valves in which the cylindrical shape has been purposely abandoned, but of those only embodiments are known which have been manufactured by sealing the contact surfaces and thus they have to be made of sealable material. Such an embodiment has been described in GB-A-1,000,335.
The invention aims to provide an apparatus for manufacturing conical objects, such as valves for bags, which do not have to be made of sealable material.
According to the invention, the apparatus comprises for each web a first pair of folding rods arranged at a vertical distance from each other and in planes at right angles to each other around which each web is led to fold the web in half longitudinally, a guiding device comprising web path deviating means to position the two folded webs at an acute angle to each other with the open edges facing each other, means for driving the thus positioned webs along the deviated path such that one folded web is inserted between the open edges of the other, means for severing the webs and means for glueing the overlapping portions of the webs.
If the apparatus is used for manufacturing conical valves for bags, it is very practical to mount a grabbing device which is able to transfer the cut valve to a valve mounting device.
The folding device may consist of two pairs of optionally freely rotating, perpendicularly intercrossing rods.
The guiding device may consist of two web path deviating bars positioned in the same planes as the ones in which the webs come out of the folding device.
The driving means may be positioned between the guiding device and the cutting device, and may consist of rotatably driven driving rolls for each of the webs, in which the centre lines of the driving rolls are at an angle with respect to each other which is equal to the supplement of the angle at which the folded webs with the open sides facing each other can be shifted into each other. This angle is preferably about 10°.
The glueing device may comprise two nozzle pipes which can cover the overlap of the shifted, folded webs with glue.
The cutting device and the grabbing device are preferably mechanically coupled.
The invention will be elucidated hereafter on the basis of the drawing, in which by means of an example an installation according to the invention is shown. In the drawing,

Figure 1 shows an outline of the apparatus in question in perspective,
Figure 2 shows at a larger scale the upper portion of the folding device in perspective, and
Figure 3 shows at a larger scale the guiding device and the other devices positioned nearby in perspective.

The apparatus shown in Figure 1 for manufacturing conical objects substantially comprises two parallel, horizontal shafts 1 and 2 for rotatably supporting two rolls 3 and 4 of flexible material, in which roll 3 provides an upper web 5 and roll 4 a lower web 6.
Both webs 5 and 6 pass through a folding device 7, shown in more detail in Figure 2, and in which the webs are not only folded in two but also changed in direction over 90°.
After that the webs 5 and 6 enter a guiding device 8 in which the folded webs are shifted into each other with the open sides facing each other. At that point there is also a driving means 9, a cutting device 10, a glue supply 11, being elucidated in more detail in Figure 3, and a grabbing device 12 which transfers the finished conical valve, after it has been cut perpendicular to the bisectrice of the angle between the webs, to a valve mounting device (not shown). This latter action particularly implies, that the new valve is directly used in the usual manner for finishing a bag. The action of the two webs being shifted into each other will continue undisturbed in order to form the next conical valve.
In Figure 2 the upper halve of the folding device 7 is shown, in which it is understood that the lower halve is the symmetrically reflected image of Figure 2. The upper halve of the folding device consists of two pairs of optionally freely rotating, perpendicularly intersecting rods 13 and 14. The rod 14 supporting the web folded in two, naturally has a length being about half the length of rod 13 which supports the still unfolded web.
The guiding device 8 comprises two web path deviating bars 15 and 16, positioned in the same planes as the ones in which the webs 5 and 6 come out of the folding device 7. Preferably the webs 5 and 6 are deviated in such a manner, that they move towards each other at an angle of 2x5° while remaining in the same plane.
After this, the open sides of the webs 5 and 6 are positioned on the inside of the said angle.
The driving means 9 consists of two rotatably driven driving rolls 17 and 18 with centre lines being at a mutual angle which is equal to the supplement of the angle at which the open side of the folded web 6 is shifted through the driving roll 18 into the open side of the folded web 5. This angle is optional, but preferably it is about 2x5°, so that the mutual angle of the centre lines will be 170°. In the shown embodiment the driving rolls 17 and 18 pull the webs 5 and 6 both about the web path deviating bars 15 and 16 of the guiding device 8 and over the optionally freely rotating rods 13 and 14 of the folding device 7. This guarantees that correct folds are applied and that the webs are shifted into each other correctly.
In Figure 3 the position of the cutting device 10, the glue supply 11, and the grabbing device 12 with respect to each other are shown. The glue supply consists of two nozzle pipes 19 and 20 that can cover the overlaps 21 with glue. As soon as that has been done, the cutting device 10 and the grabbing device 12 start acting in the known manner to transfer the finished valve to a valve mounting device (not shown).
It is remarked, that although the invention is described on the basis of an apparatus for manufacturing conical valves, the merit of the invention can of course also be applied in the manufacture of other conical objects.

Claims

1. Apparatus for manufacturing conical objects from two webs (5, 6) of flexible material supplied from respective rolls (3, 4), comprising for each web a first pair of folding rods (13, 14) arranged at a vertical distance from each other and in planes at right angles to each other around which each web is led to fold the web in half longitudinally, a guiding device (8) comprising web path deviating means (15, 16) to position the two folded webs at an acute angle to each other with the open edges facing each other, means (9) for driving the thus positioned webs along the deviated path such that one folded web is inserted between the open edges of the other, means (10) for severing the webs and means (11) for glueing the overlapping portions of the webs.

2. Apparatus according to claim 1 for manufacturing conical valves for bags, characterized in that a grabbing device (12) is mounted which is able to transfer the cut valve to a valve mounting device.

3. Apparatus according to claim 1 or 2, characterized in that the folding device (7) consists of two pairs of optionally freely rotating, perpendicularly intercrossing rods (13, 14).

4. Apparatus according to any of the preceding claims 1-3, characterized in that the guiding device (8) consists of two web path deviating bars (15, 16) positioned in the same planes as the ones in which the webs (5 and 6) come out of the folding device (7).

5. Apparatus according to any of the preceding claims 1-4, characterized in that the driving means (9) is positioned between the guiding device (8) and the cutting device (10), and consists of rotatably driven driving rolls (17 and 18) for each of the webs, in which the centre lines of the driving rolls are at an angle with respect to each other which is equal to the supplement of the angle at which the folded webs with the open sides facing each other can be shifted into each other.

6. Apparatus according to claim 5, characterized in that the angle at which the folded webs are shifted into each other, is about 10°.

7. Apparatus according to any of the claims 1-6, characterized in that the glueing device (11) comprises two nozzle pipes (19 and 20) which can cover the overlap of the shifted, folded webs with glue.

8. Apparatus according to any of the claims 1-7, characterized in that the cutting device (10) and the grabbing device (12) are mechanically coupled.