MXPA04004451A

MXPA04004451A - Sealing wrapper for food products, corresponding process and installation.

Info

Publication number: MXPA04004451A
Application number: MXPA04004451A
Authority: MX
Inventors: Mansuino Sergio
Original assignee: Soremartec Sa
Priority date: 2003-05-13
Filing date: 2004-05-11
Publication date: 2005-06-08
Also published as: AU2004200410B2; KR101074871B1; US20040226267A1; JP2004338804A; ES2259411T3; BRPI0402043B1; BRPI0402043A; ATE320983T1; CN100364859C; EP1477423A1; PL367933A1; KR20040098512A; PL211452B1; AR047395A1; CL43111B; AU2004200410A1; EP1477423B1; CA2456709A1; HK1072232A1; RU2335440C2

Abstract

A sealed wrapping for foodstuffs (1) such as chocolates, sweets, pralines and the like. The wrapping comprises a single sheet of wrapping material (2) forming a bent part for receiving the product (1). The wrapping is sealed by means of a single welding line (3) which extends according to a path having the ends located on the bent part (20) and which surrounds the product (1).

Description

SEALING WRAPS FOR FOODSTUFFS, CORRESPONDING PROCESS AND INSTALLATION "The present invention relates to sealed wraps (known as" tight "wrappings) for food, eg, confectionery.In the food packaging, it is necessary to take into account different requirements , first the need to ensure that the product remains unchanged for the longest period - possible after packing In order to achieve the purpose mentioned above, for some time it has been known, also in the case of small-sized foods (for example , chocolates, sweets, pralines, etc.), wrap the products in sealed wrappers of the type commonly known as "flow-pack." This wrapping technique contemplates the fact of starting from a roll of material in foil sheet that is wraps around the product in the longitudinal direction through a training device in order to create an inte rmedia tubular .. continues closed by a first longitudinal sealing line. The products to be wrapped advance in the tubular intermediate wrapper, and the assembly obtained in this way is subjected to the action of one or more closing stations. Here, the intermediate tubular casing is flattened, welded and cut in the areas of separation between successive products in order to create individual casings. An example of this technique is described in EP-A-0 957 043. Even without taking into account considerations of a functional nature (related, for example, to the fact that the regions where the transverse end welds of the shell of Flow-pack type splices the longitudinal or sealed welding line can constitute critical areas for the purposes of the seal), the flow-pack type wrapper evidently appears as the result of an industrial process. This wrapping is therefore far from being suitable for use in the case of products (for example, some confectionery products) that are intended to be associated with a more traditional type wrapping, for example, traditional wraps for sweets, with the product contained in a wrapper having one end or both ends bent to form fan-like ends (fan-shaped twist wrap). For this reason, solutions have already been proposed in order to reproduce these more traditional forms of wrapping. A solution of this type is described, for example, in WO-A-02/22445: individual segments of an intermediate piece of a flow-pack type of wrap, wrapped around the product in order to form a tubular structure is subjected to tightening in a radial direction in order to form areas of creases that remind I point the ends wrapped with fan-type twist of a traditional candy wrap. The main drawback of this type of wrapping lies in the fact that the sealing action in relation to an external environment must be carried out with precision in the areas subject to radial compression. The tests show, however, that, even resorting to a wrapping material that can be subjected to at least partial melting in the areas subjected to radial compression, the degree of effective sealing in relation to the external environment is relatively modest. This fact is understandable, since, in the areas mentioned above, the wrapping material subjected to compression in a radial direction tends to form folds in a totally uncontrolled manner. As a result, folds or ridges are formed that have a completely random pattern, between which communication paths with the external environment can easily remain open or in which communication paths with the external environment can easily be opened after a period of time. short time Solutions that allow obtaining an excellent degree of sealing in relation to the external environment are described in EP-A-0 591 742 and EP-A-0 790 184. In both cases, however, are solutions in which an envelope comprising two elements of sheet material is used. The purpose of the present invention is to provide an enclosure capable of combining with an extreme structural simplicity and therefore with a simplicity and extreme economy of manufacture, excellent sealing qualities (hermetic sealing). In accordance with the present invention, the aforementioned purpose is achieved thanks to an envelope having the features mentioned in the appended claims. The invention also contemplates the corresponding manufacturing process, as well as the corresponding plant. Basically, the solution according to the present invention is characterized in that it provides an envelope comprising a single sheet element closed by a single welding or sealing line. For the aforementioned purpose, a sealed food wrapper is provided, comprising: - A wrap sheet with a folded or hollow part that receives at least one food product; and - A sealing line extending for the purpose of closing said leaf of err along a path surrounding said at least one food product and having the ends placed in a position corresponding to said part of said sheet. side. Obviously, the term "wrapping sheet" is understood herein as indicating any sheet material that can effectively isolate the product from the external environment.

Again, the term "path" surrounding the food product is understood herein as indicating a path that extends around the product (a path preferably has a generally arc-shaped pattern, ie, the shape of the letter C), usually privileging a rather narrow relation of the wrapping, thus ensuring a wrapping of the product which is the most adherent possible, this being a result that can be favored by possible actions of smoothing, brushing or other operations.The invention will be described below, simply to title of non-limiting example, with reference to the accompanying drawings, in which: - Figures 1 to 5 illustrate successive steps of a process designed to provide a wrapper in accordance with the present invention, and - Figure 6 is an elevation side of the corresponding plant The exemplary modality illustrated in the following refers to the production of a wrapper for a food product 1 consisting, for example, of a confectionery product, for example, chocolate, candy, pralines, etc., in various forms. In particular, it can be a product that has a coating, for example, coating of ground hazelnuts, striped coconut, striped meringue, etc. In any case, neither the dimensions nor the shape, nor the nature and / or the specific characteristics of the product (individual or compound) constitute an element of limitation of the present invention. The product 1 is designed to be wrapped in an envelope consisting of a single sheet element 2 of a laminar wrapping material of the type widely used for wrapping confectionery products. It is therefore a material in sheet form capable of effectively isolating the product from the external environment. It can be, for example, an aluminum sheet and / or plastic material. The material in question may be a "blended" material, ie, a material comprising at least one first layer, designed to constitute the outer part of the finished wrapper, and a second layer, designed to constitute the inner part of the finished wrapper. finished wrapping, and presenting, for example, thermal sealing capability characteristics. A typical example of combined material of this nature is a material consisting of an external sheet made of aluminum coated on the inner surface with a plastic material, for example, polyethylene. As will be seen in this case, that the solution described here is in no way limited to a particular choice of sheet wrapping material or to the adoption of particular technical procedures for sealing / sealing the wrapping material itself. In the example embodiment illustrated here (which, again, is emphasized, is simply an example), the process is considered to start from a sheet material element 2 having, for example, the shape of a square or of an approximately square leaf with a side of a few centimeters in length. As will be more clearly understood in the following, said individual wrapping element can in fact be defined by a portion or segment of a continuous sheet material that is unwound from a reel and is subjected to segmentation in order to form individual elements of a reel. envelope. In the wrapping elements 2 represented by FIG. 1, the product or article 1 to be wrapped is then placed in an approximately central position. In the drawings, said product is represented in the form of a body having a parallelepiped shape; however, it will be understood that the product 1 can have any shape. In a further step of the wrapping process, the sheet material element 2 is wrapped around the product 1 to form: - A folded part 20 which in fact receives the product 1; and - Two lateral branches 21, extending to i i from the folded part 20 and are on the opposite faces of the product 1 (upper face and lower face in the orientation illustrated). From the examination of figure 3, it can easily be seen that the wrapping sheet is wrapped around the product 1 in such a way that a type of bag or envelope is formed wherein the side branches 21 retain a substantially flat orientation whatever the shape of the product 1. ' In practice, the two lateral branches 21 are substantially parallel to each other, separated by a distance substantially corresponding to the thickness or height of the product 1. In a further step of the process, as shown in Figure 4, the two lateral branches 21 are connected between them by a sealing line 3. The sealing line 3 connects the two branches of the wrapping sheet in accordance with a path that surrounds the food product 1, - It is therefore generally a trajectory that has a pattern overall, in the form of an arc, that is, in the form of a letter C, with the ends located in a position corresponding to the bent part 20, said bent part obviously already performs a sealed receiving action for the product 1, without the need to form connection lines.

In order to form the sealing line 3 it is possible to resort to a wide range of techniques widely adopted in the wrapping industry, in particular, for wrapping food. Accordingly, the sealing line 3 can be made, for example, by means of heat sealing, cold sealing, sealing with or without welding material, ultrasonic sealing, laser sealing, or possibly through a simple embossing action. . As for the path of the sealing line 3, even though it retains the general wrapping pattern with respect to the product 1, it is possible to adopt different options. The tests carried out by the applicant of the present invention indicate that the choice of a trajectory with a substantially continuous arch pattern is preferable, therefore, substantially without apexes and / or splices of wrapping or folds of wrapping material. say, without splicing more than two layers of wrapping material). Areas of this type could result, for example, from the connection of two contiguous rectilinear segments and could form the basis of phenomena of concentration of coercive states that can weaken the seal of the seal line. As an additional finishing operation, the wrapper presented in FIG. 4 can be completed by forming one or two parts fan-shaped in a fan-shaped manner 4 in order to provide the overall envelope with the typical appearance of a candy wrapper. This result can be obtained (in a known manner) by twisting the longitudinal end or the longitudinal ends of the envelope, or by resorting to other methods whose purpose is to obtain a fan-shaped twist. It will be noted that the possible formation of said wrapped parts with fan-shaped torsion (which - as already emphasized - does not represent an imperative characteristic of the solution described here) does not adversely affect the sealing characteristics of the sealing line 3 This is in fact obtained by connecting two lateral branches 21 of the wrapping material in sheet form 2 while being maintained in a condition of substantial planarity. The connection between the two branches 21 is therefore extremely intimate and continuous and therefore resists, without weakening, any possible subsequent deformation of the envelope. Turning now to an examination of the plan diagram of Figure 6, the reference numeral 10 refers to an unwinding assembly from which the sheet material that will form the wrap 2 is unwound. Starting from the unwind device 10 (which I is of known type), the sheet material 2 is fed into a forming assembly 12 designed to provide the sheet material with a general U-type shape comprising the folded portion 20 and the side branches 21 (see Figure 3) . Likewise, the forming device 12 can be considered in itself as an element of known type. In fact, it can be obtained in accordance with the widely used criteria for preparing training devices which, in the packaging machines of the flow-pack type, close the sheet material according to a general tubular pattern. While the tubular casing formed in flow-pack type machines (or in the solution described in document W0-A-02/22445) is typically characterized because it is closed by a longitudinal sealing line and because it has a substantially circular transverse profile , the corresponding intermediate piece obtained in the plant of figure 2, is open to the window (see, again figure 3), in the sense that the two lateral branches 21 are not connected between them in a position corresponding to its distant margins. Again, the intermediate piece represented by Figure 3 presents a general U-shaped development, with the two lateral branches 21 held in a substantially flattened position. As has already been said, this fact is important to achieve a continuous and intimate connection, provided through the sealing line 3, which is at the base of the sealing characteristics of the final wrap. The feeding of the products 1 to be wrapped in the direction of the area where the forming device 12 operates is ensured through a conveyor belt 14 consisting, for example, of a motor-driven conveyor belt of the type widely used in plants for pack food. Said conveyor 14 cooperates with the forming device 12 to cause the products 1 to be inserted in the folded wrapping material to form a U shape are separated at regular distances, thus creating a charging station designated globally by the reference number 16. Under these conditions, fed by an additional conveyor (usually the intermediate piece of wrapping material constitutes an active element, since it transports with it the products 1 located there), the products are brought into a position corresponding to a closing station 18 , which forms the sealing line 3 and cuts the tape of wrapping material in the areas left free by the products in order to provide different wraps.

According to the structure known per se, the closing station 18 can be of the vertical reciprocating type and can therefore comprise an anvil base or part 18a, as well as an active mobile element 18b that moves vertically and is lowered periodically on the Anvil portion 18a thereby creating the sealing line 3 and cutting the individual wraps. For the aforementioned purpose, the base portion 18a and / or the active element 18b usually have surface indentations defining the path of the sealing line 3. The base part 18a and / or the active element 18b may have elements associated therewith. of heating and / or ultrasound generators (not specifically illustrated but are of a known type) when the adopted sealing technology includes the application of heat and / or ultrasound. In a useful manner (and also in accordance with the criteria known per se), the closing station 18 can be constructed for the purpose of carrying out, in addition to the vertical movement carried by the base part 18a and the active element 18b to close between them with the interposition of the wraps, also a movement of "tracking" the advance of the wraps. Said movement of tracking causes the action of forming the sealing line 3 to be carried out in conditions practically without relative movement. The fixed anvil part 18a can have an upper surface that is at least slightly hollowed to ensure that the sealing line 3 (made with the sheath comprised between the parts 18a and 18b closed between them) is obtained under conditions of perfect symmetry. Usually, a sealing unit 18 is associated therewith with cutting elements (not specifically illustrated, but of a known type) whose purpose is to cause the continuous belt of the sheet material 2 to be divided afterwards or concomitantly with the formation. of the sealing line 3 in order to provide individual wrappings, for example, the wrapping designated by the letter C in Figure 6. The reference number 20 refers to a forming station, wherein one or both longitudinal ends of the casing C is subjected to an additional treatment (for example, twisting), in order to form the fan-shaped parts 4 of Figure 5. The casings thus terminated are joined at a linking station 22 with the object to form the subsequent packing. As previously stated, the formation of one or more parts in the form of a fan 4 constitutes an optional and non-mandatory step of the solution described therein. Accordingly, it will be understood that, without opposing the principle of the invention, the details of the implementation of the modalities can vary, to a large extent, in relation to what is described and illustrated simply by way of non-limiting example, without going beyond the scope of the invention in accordance with that defined in the appended claims.

Claims

CLAIMS A sealed food wrapper, comprising: - a wrapping sheet (2) with a folded part (20), which receives at least one product (1), and - a sealing line (3), which extends in order to close said wrapping sheet (
2) along a path surrounding said at least one product (1) and having the ends located in a position corresponding to said bent part (20). The wrapping according to claim 1, characterized in that said wrapping sheet (2) consists of a material that can be subjected to sealing with a technique selected from the group consisting of: heat sealing, cold sealing, sealing with material of welding, sealing without welding material, ultrasonic sealing, laser sealing, embossing. The casing according to claim 1 or according to claim 2, characterized in that, in a position corresponding to said sealing line (
3), the casing is constituted by sheet material (2) subjected to an operation selected within the group consisting of: heat sealing, cold sealing, sealing with welding material, sealing without welding material, ultrasonic sealing, laser sealing, embossing. The casing according to any of the preceding claims, characterized in that said sealing line (3) extends along a path without apices. The wrapping according to any of the preceding claims, characterized in that said sealing line (3) extends along a free path of areas of splicing of shoulders or folds of wrapping material (2). The wrapping according to any of the preceding claims, characterized in that said wrapping sheet comprises two side branches' (21), which extend from said folded part (20) on opposite sides of said at least one product. (1), said sealing line (3) extending so as to connect with said lateral branches (21). The casing according to claim 6, characterized in that, at least in the area of said sealing line (3), said lateral branches (21) are substantially coplanar with respect to each other. The casing according to claim 6 or according to claim 7, characterized in that, at least in a position corresponding to said sealing line (3), said lateral branches (31) are substantially free of folds or highlights The wrapper according to any of the preceding claims, characterized in that said sealing line (3) extends in accordance with a general arc-shaped path. The wrapping according to any one of the preceding claims, characterized in that it also comprises at least one end part (
4) having a fan-like shape. 11. The process for sealing a food wrapper (1) said process comprises the steps of: - forming (12) a wrapping sheet (2) with a folded part (20), - placing said at least one product (1) ) in said bent part, and - forming (18) a sealing line (3), which e; extends in order to close said wrapping sheet (2) along a path surrounding said at least one product (1) and has the ends located in a position corresponding to said folded part (20). The process according to claim 11, characterized in that it comprises the operation of making said wrapping sheet (2) with a material that can be subjected to sealing with a technique selected from the group consisting of: heat sealing, Cold sealed, sealed with welding material, sealed without welding material, laser sealed, embossed. The process according to claim 11 or according to claim 12, which is characterized in that it comprises the operation of producing said sealing line (3) through a selected operation within the group consisting of: heat sealing, cold sealing, sealing with welding material, sealing without welding material, sealing with ultrasound, laser sealing, embossing. The process according to any of claims 11 to 13, characterized in that it comprises the operation of forming (18) said sealing line (3) along an apex-free path. The process according to any of claims 11 to 14, characterized in that it comprises the operation of forming (18) said sealing line (3) along a free path of areas of splicing of ridges or folds of material of wrapper (2). The process according to any of claims 11 to 15, characterized in that it comprises the steps of: - forming (12) on said wrapping sheet two lateral branches (21) that extend from said folded part (20) on opposite sides of said at least one food product (1), and - forming (18) said sealing line (3) in such a way that it connects said lateral branches (21). The process according to claim 16, characterized in that it comprises the operation of maintaining said lateral branches (21) substantially coplanar with respect to each other in the area of formation of said sealing line (3). The process according to claim 16 or according to claim 17, characterized in that it comprises the operation of maintaining said lateral branches (31) substantially free of folds or ridges at least in a position corresponding to said sealing line (3) . The process according to any of claims 11 to 18, characterized in that it comprises the operation of forming (18) said sealing line (3) in accordance with a general arc-shaped trajectory. The process according to any of claims 11 to 19, characterized in that it comprises the operation of forming (20) in said envelope at least one end part (4) having a fan-like conformation. A plant for sealing wrapping for food (1), comprising: - a forming device (12) for forming a wrapping sheet (2) with a folded portion (20); - a loading station (16) for placing at least one food product (1) in said bent part; and - a sealing station (18) configured to form a sealing line (3), which extends for the purpose of closing said wrapping sheet (2) along a path surrounding said at least one food product (1) and has the ends located in a position - corresponding to said folded part (20). The plant according to claim 21, characterized in that said sealing station (18) is a station that operates in accordance with a technique selected from the group consisting of: heat sealing, cold sealing, sealing with welding material , sealed without welding material, sealed with ultrasound, laser sealed, embossed. The plant according to claim 21 or according to claim 22, characterized in that said sealing station (18) is configured to form said sealing line (3) along an apex-free path. The plant according to any of claims 21 to 23, characterized in that said sealing station (18) is configured to form said sealing line (3) along a free path of splice or crease areas. of the wrapping material (2). The plant according to any of claims 21 to 24, characterized in that said forming device (12) is configured to form (12), in said wrapping sheet, two lateral branches (21), which extend to from said bent part (20) on opposite sides said at least one food product (1) and in that said sealing station (18) is configured to form (18) said sealing line (3) in such a way as to connect said lateral branches (21). The plant according to any of claims 21 to 25, characterized in that said sealing station (18) is configured to maintain said side branches (21) substantially coplanar with respect to each other in the area of formation of said sealing line (3) . The plant according to any of claims 21 to 26 characterized in that said sealing station (18) is configured to maintain said lateral branches (31) substantially free of folds or ridges at least in a position corresponding to said line sealing (3). The plant according to any of claims 21 to 27, characterized in that said sealing station (18) is configured to form said sealing line (3) in accordance with a general arc-shaped trajectory. The plant according to any of claims 21 to 28, characterized in that it comprises a forming station (20) to form, in said envelope, at least one end part (4) having a fan-like shape.