EP0461090A1

EP0461090A1 - Method and device for folding the closed mouthportion of a filled bag, and a bag thus obtained

Info

Publication number: EP0461090A1
Application number: EP91830244A
Authority: EP
Inventors: Giuseppe Cardini; Ugo Chiti
Original assignee: Garibaldo Ricciarelli Srl
Current assignee: Garibaldo Ricciarelli Srl
Priority date: 1990-06-06
Filing date: 1991-06-05
Publication date: 1991-12-11
Also published as: IT1241725B; IT9009417A1; BR9102320A; IT9009417A0; JPH05213302A

Abstract

After the flattening by bellows of the material of tubular development of the mouth of the bag, the latter undergoes a first fold (12) in one direction at the base and a second fold (14) in the opposite direction at a distance from the base which is not greater than half the overall height dimension of said flattened mouth; a third fold (22) is imposed on the end portion of the mouth, with straightening of the first fold (12); this is followed by the turning down of the mouth folded to double thickness, until against the filled bag (S).

Description

The invention relates to the final packaging of bag-type envelopes made of flexible material and for the most part heat-sealing or somehow sealable, in order to render the packaging operation easy, the final state being finished without cutting the end of the bag, and the use upon opening of the bag and during the consumption of the contents of the latter practical. These and other aims and advantages will become clear from the following text.
A first subject of the invention is a method for the closure and finishing of bag-type envelopes using operations which follow one another in sequence after filling, comprising flattening by bellows of the material of tubular development of the mouth of the bag, weldingfor the most part systematic - and folding. According to the invention, during the advance of the manufactured article in the direction of the plane of lying of the flattened mouth, the latter undergoes a first fold in one direction at the base and a second fold in the opposite direction at a distance from the base which is smaller than half the overall height dimension of said flattened mouth; a third fold is imposed on the end portion of the mouth, with straightening of the first fold.
Subsequently, the turning down of the mouth folded to double thickness is envisaged, as continuation of the straightening, until against the end portion and against the filled bag.
The weld can be formed at a distance from the first fold and from the base, which is greater than the distance of the second fold from said first fold.
A second subject of the invention is a device for effecting closure and finishing of bag-type envelopes made of heat-sealing material after their filling. This device comprises means of folding which operate during the advance in the direction of the plane of lying of the flattened mouth, in order to effect: two opposite folds, a first (while stationary) at the base and a second at a distance - from the base - which is smaller than or equal to half the overall height of the flattened mouth, and then a third fold in the end part adjacently to the first fold, with straightening of the first fold.
The device also comprises means for continuation of the straightening folding with turning down against and onto the end part, for the subsequent application of an adhesive or the like.
A further subject of the invention is a bag with a flattened and folded mouth, in which said mouth is folded with the end part against the bag and with two other adjacent portions folded against one another and against said end part.
The invention will be more clearly understood by following the description and the attached drawing, which shows a non-limiting exemplary embodiment of the invention itself and in which:

Fig. 1 shows a general diagram of a device for closing bags according to the invention;
Fig. 2 shows enlarged details illustrating some of the significant stages of the closing operation, in views like that indicated by II-II in Fig. 1, and
Fig. 3 is a local cross section according to III-III in Fig. 2.

According to what is illustrated in Fig. 1, 1 very generally indicates a continuous conveyor which can have a continuous or, better, intermittent movement, with a series of seats 3 at a distance from one another, to receive bags which are open at the top and the filling and then the closure of which are carried out. In a completely general manner, 5 indicates a unit intended for the formation and filling of the bags. The bags, indicated by S, have a mouth IS which is completely open upwards, as is indicated in the states A-E in the drawing, in the lateral view in Fig. 1 and in the transverse cross-section 3-3 of the stages A-E in Fig. 2. The walls of the bag and in particular of its mouth IS are then deformed by bellows as shown in the cross-section in Fig. 3 and flattened, as occurs in stages F and G in particular, with a lying position which is situated in a symmetrical position in the filled bag S and in the plane containing the direction of advance of the conveyor 1 according to the arrow f in Fig. 1. The operation of deformation and flattening of the mouth IS, as shown in the state in station F and in Fig. 3, is effected using tools of known type, as said defromation is conventional for these types of packaging. Subsequently, in station G, by means of tools 10 which draw near symmetrically, there is made - while stationary - a transverse weld SA between the walls of the flattened mouth IS, the weld being effected in an intermediate and adjustable position of the height of the flattened mouth IS. Immediately afterwards, in station H, a double fold is effected along a first folding line 12 at the base of the flattened mouth and a second opposite folding line 14 in an intermediate position immediately below or above the weld SA effected using the tools 10. This is brought about using a series of tools such as those indicated by 16, 18 and using a blade 20 to define precisely and accompany the deformations which can be effected by means of movement of the tools 16, 18. In particular, the tool 16 is shaped in the form of a square with a slot, into which the blade 20 penetrates in order to effect the folds 12 and 14; the tool 18, similar and symmetrical to 16, stabilizes the material in this stage. In a subsequent station, indicated by I, the first fold 12 is straightened and the fold 14 comes to be situated in the plane of symmetry, while a third fold 22 is effected in an intermediate position between the end of the flattened mouth IS and the weld SA; the end part of the flattened mouth IS comes to be brought near to the upper bulk of the bag S, precisely as shown in station I. This can be brought about using the same previous tools or using blade- type tools 24, 26 which deform the material and using a tool 28 which straightens the fold 12. A further stage, in station L, causes the turning down of the part of the flattened mouth IS of double thickness, comprised between the base fold 12 and the third fold 22, until it is brought near to the end part of the flattened mouth, which has already been brought near to the bag. This operation too can be brought about using a tool such as that indicated by 30. In a subsequent station, an adhesive or other means for stabilizing the state reached can be applied. It should be noted that the end of the material IS remains concealed, when the state in stage L is reached, and it is therefore not necessary to have recourse to cutting it to make it regular.
With the arrangement illustrated, it is possible to bring about a very convenient weld and stabilization of the folded mouth and it is moreover also possibleafter opening the bag by cutting below the weld SA - to bring about the possibility of reclosing the bag with its residual contents, so as to bring about protection and preservation of the product even after initial opening of the bag.
It is understood that the drawing only shows an exemplary embodiment which is given only by way of practical demonstration of the invention, it being possible for the invention to vary in form and arrangement without moreover leaving the scope of the idea which forms the invention itself. Any presence of reference numbers in the enclosed claims has the purpose of facilitating reading of the claims with reference to the description and to the drawing, and does not limit the scope of protection represented by the claims.

Claims

A method for the closure and finishing of bag-type envelopes made of heat-sealing material after their filling, using operations which follow one another in sequence, comprising flattening by bellows of the material of tubular development of the mouth of the bag, welding and folding, wherein, during the advance of the manufactured article in the direction of the plane of lying of the flattened mouth (IS), the latter undergoes a first fold (12) in one direction at the base and a second fold (14) in the opposite direction at a distance from the base which is smaller than or equal to half the overall height dimension of said flattened mouth, and wherein a third fold (22) is imposed on the end portion of the mouth, with straightening of the first fold (12).
The method as claimed in the preceding claim, wherein turning down of the mouth folded to double thickness is envisaged, as continuation of the straightening, until against the end portion and against the filled bag.
The method as claimed in preceding claims, wherein the weld (SA) is formed at a variable distance from the first fold (12) and from the base, which can be greater or smaller than the distance of the second fold (14) from said first fold (12)
A device for effecting closure and finishing of bag-type envelopes made of heat-sealing material after their filling, which comprises means of folding which operate during the advance in the direction of the plane of lying of the flattened and welded mouth, in order to effect: two opposite folds (12; 14), a first at the base and a second at a distance - from the base - which is smaller than or equal to half the overall height of the flattened mouth, and then a third fold (22) in the end part adjacently to the first fold, with straightening of the first fold.
The device as claimed in claim 4, which comprises means for continuation of the straightening folding with consequent turning down against and onto the end part.
A bag with a flattened mouth, in particular welded and folded, wherein said mouth is folded with the end part against the bag and with two other adjacent portions folded against one another and against said end part.
A method as described and illustrated.
A device as described and illustrated.
A bag as described and illustrated.