JP2004025670A - Method for forming groove part for opening container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form an easily opening groove part always having a proper depth to the surface of the expanded sheet made of a resin of a container, which is equipped with a flow channel between two bonded resin sheets by expanding at least one resin sheet from the surface of the resin sheet, without stopping the feed of the container. <P>SOLUTION: In the method for forming the groove part for opening the container, the surfaces of the resin sheets 1a and 1b are irradiated with a laser L for forming the groove part and the forming range of the groove part along the irradiation direction is larger than the expanded quantity of the resin sheets 1a and 1b in the forming region of the flow channel 2. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides a container having a flow path formed by swelling at least one of these resin sheets from the surface between two bonded resin sheets. The present invention relates to a method for forming a groove for easy opening on a surface of a sheet.
[0002]
[Prior art]
FIG. 2 shows an example of a closed container in which a groove for easy opening is formed. Reference numeral 1 denotes a container, and the container 1 is formed at its edges with two front and rear rectangular resin sheets 1a and 1b forming side surfaces and a resin sheet 1c forming a bottom surface. By laminating at the sealed portions 1d and 1e, a space S surrounded by the sheets 1a, 1b and 1c is provided inside, and the sheet 1c is formed to be self-supporting with the bottom as the bottom.
[0003]
Reference numeral 2 denotes a flow path formed at one (left side in the figure) of the pair of corners formed at the upper end of the container 1 and formed by laminating the sheets 1a and 1b. The flow path 2 is formed by swelling the individual sheets 1a and 1b from the surface thereof. The flow path 2 extends from the upper end of the space S toward the one corner, and the periphery thereof is a seal 1d. Surrounded by
[0004]
Further, a linear groove 2a is formed on the surface of one corner along the direction crossing the flow path 2, and by cutting the flow path 2 along the groove 2a, the container 1 can be easily manufactured. And the articles stored in the space S can be poured out through the flow path 2. Reference numerals 2b denote recesses respectively formed at both ends of the groove 2a by recessing the seal portion 1d toward the flow path 2. Due to the presence of these recesses 2b, when the one end is twisted to cut the flow path 2, the force received by the container 1 is concentrated on the groove 2a via the recess 2b, and the ease of opening of the container 1 is further improved. improves.
[0005]
[Problems to be solved by the invention]
By the way, in recent years, when forming the groove 2a, a laser is applied to the formation portion of the groove 2a from the front and back sides of the container 1 so that the focal point matches the formation portion, and the surface of the sheet 1a, 1b is irradiated. Is formed by sublimating the resin constituting the groove 2a using laser energy. However, for example, as shown in FIG. 2, when the flow path 2 forms a three-dimensional shape in which the sheets 1 a and 1 b are swelled back and forth, the laser output and the focal point are controlled by the laser out of the portion where the groove 2 a is formed. Is set to such an extent that a groove 2a having an appropriate depth is formed at the point closest to the output portion (the outer peripheral end of the portion where the flow path 2 is formed; the point indicated by arrow A in FIG. 2). Sufficient energy cannot be obtained in other parts that are far apart from each other, and as a result, it is difficult to form the groove 2a, and there is a problem that the ease of opening the container 1 is reduced.
[0006]
Conversely, if the output and focus of the laser are set to such an extent that the groove 2a having an appropriate depth is formed on the surface of the seal portion 1d (the range indicated by the arrow B in FIG. 2), Since it is relatively close to the output section, the applied energy becomes excessive, and as a result, the groove 2a becomes too deep, the strength of the sheets 1a and 1b decreases, and the sheets 1a and 1b are unnecessarily torn. Problem arises. Therefore, conventionally, the distance between the output portion and the portion where the groove 2a is formed is kept constant by moving the output portion of the laser along the surface shape of the portion where the groove 2a is formed. However, this method requires a moving mechanism for moving the output section along the surface shape, and requires time to move the output section. There is a problem that it is necessary to stop some parts.
[0007]
[Means for Solving the Problems]
The present invention has been made to solve the above-described problem, and a flow formed between two bonded resin sheets by causing at least one of the resin sheets to swell from the surface thereof. A method of forming a container opening groove for providing a groove along a direction crossing the flow path on the surface of the swelled resin sheet of a container provided with a path, so that the container can be easily opened. Thereupon, the laser for forming the groove portion is irradiated toward the surface of the resin sheet that has swelled, and the range of formation of the groove portion along the irradiation direction by the laser irradiation is such that the flow path is formed. It is characterized in that it is larger than the swelling amount of the resin sheet at the site.
[0008]
Furthermore, it is desirable that the range of formation of the groove along the direction in which the groove is extended by the laser irradiation is equal to or longer than the entire length of the groove.
[0009]
Further, as the laser, for example, a laser output through a galvano-polarizing lens can be used.
[0010]
The groove may be formed by irradiating the surface of each of the resin sheets with the laser beam without stopping the conveyance of the container during the conveyance of the container.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. Here, FIG. 1 is for explaining the embodiment of the present invention, and is a cross-sectional view of the vicinity of the flow path 2 along the forming direction of the groove 2a. Further, in the following description, members having the same configuration as the members shown in FIG. 2 are denoted by the same reference numerals as those in FIG.
[0012]
According to the present invention, a laser is applied to the formation part of the groove 2a in the container 1 from the front and back sides of the container 1 so that the focal point matches the formation part, thereby forming the surfaces of the sheets 1a and 1b. The groove 2a is formed by sublimating the resin to be formed by using the energy of the laser, which is the same as the above-described conventional groove forming method.
[0013]
On the other hand, in the method of forming the groove 2a according to the present invention, as shown in FIG. 1, the formation range C of the groove 2a along the irradiation direction by the irradiation of the laser L is changed to the sheet 1a, It is set to be larger than the bulge amount D of 1b. Further, in the present invention, the formation range E of the groove 2a along the extending direction of the groove 2a by the irradiation of the laser L is set to be equal to or longer than the total length F of the groove 2a.
[0014]
Here, as the laser L that satisfies the above setting conditions, for example, a laser output via a galvano-polarizing lens can be used. In this laser L, a laser oscillated from a laser oscillator, such as a carbon dioxide gas laser, is output through a galvano polarizing lens, so that the focal depth of the output laser L (corresponding to the formation range C of the groove 2a). In addition, for example, a variation of about ± 5 mm is provided along the irradiation direction. Normally, the swelling amount D of the sheets 1a and 1b at the portion where the flow path 2 is formed is about 1 to 6 mm. Therefore, if the focal depth of the laser L fluctuates about ± 5 mm, the irradiation of the The groove 2a having an appropriate depth can be formed at the same time at the formation site of the groove and the surface of the seal portion 1d.
[0015]
In the laser L output through the galvano polarizing lens, the energy applied to the sheets 1a and 1b at the irradiation site due to the variation in the depth of focus is smaller than that of the laser used in the conventional groove forming method. Therefore, it is necessary to set the output of the laser L higher than that of the laser used in the conventional groove forming method. For example, in a laser L output via a galvano polarizing lens, a single irradiation is performed so that the bulging amount D is about 1 to 6 mm at the formation portion of the flow path 2 and the surface of the seal portion 1d with an appropriate depth. In order to form the groove 2a, an output of about 5 to 30 watts is required.
[0016]
In the method of forming the groove 2a according to the present invention, the groove 2a having an appropriate depth is simultaneously formed in the formation part of the groove 2a (the formation part of the flow path 2 and the surface of the seal part 1d) by one irradiation. Therefore, a moving mechanism for moving the output portion of the laser L along the surface shape of the flow path 2 is not required. In addition, since the irradiation time of the laser L is extremely short, there is no need to stop the container 1 with respect to the output unit when forming the groove 2a. Therefore, in the method of forming the groove 2a according to the present invention, for example, during the transportation of the container 1 during the manufacturing process of the container 1, the moving speed of the container 1 is accurately measured using a rotary encoder or the like, and the moving speed is determined in accordance with the moving speed. By irradiating the laser L to the front and back of the resin sheets 1a and 1b respectively at the time intervals, without stopping the conveyance of the containers 1, the grooves 2a having the appropriate depth are formed at the portions where the grooves 2a are formed in the individual containers 1. 2a can be formed.
[0017]
It should be noted that the present invention is not limited to the above embodiment, and it is needless to say that the present invention can be arbitrarily changed according to a specific use environment or the like without departing from the gist of the present invention. For example, the laser L that can be used in the present invention is not limited to a carbon dioxide laser that is output through a galvano-polarizing lens, and a single irradiation simultaneously forms a groove 2a having an appropriate depth in a formation portion of the groove 2a. Whatever is possible is possible. Further, a groove 2a forming equipment capable of performing the method of forming the groove 2a according to the present invention is additionally installed in the manufacturing apparatus of the container 1 having no laser groove 2a forming equipment, or a laser groove 2a forming equipment is provided. The container 1 is manufactured in advance using a manufacturing apparatus, and the container 1 is stopped by a method according to the present invention with respect to the moving container 1 in a later step (for example, a finishing step or an inspection step). Instead, it is also possible to form the groove 2a.
[0018]
In the method of forming the groove 2a according to the present invention, the formation range C of the groove 2a along the irradiation direction by the irradiation of the laser L is determined by the swelling amount D of the sheets 1a and 1b in the formation part of the flow path 2. Due to the large size, even when the sheets 1a and 1b themselves have slight irregularities in the vertical direction in FIG. 1, the groove 2a having an appropriate depth can always be formed. A member (stabilizer) 3 for holding down the surfaces of the resin sheets 1a and 1b is provided so as not to overlap with the irradiation range of the laser L, and unnecessary movement along the unevenness of the sheets 1a and 1b and the vertical direction in FIG. May be prevented.
[0019]
Further, in the above embodiment, the method of the present invention is applied to the container 1 in which the flow path 2 is formed by expanding both of the individual sheets 1a and 1b. It goes without saying that the present invention is also applicable to a container in which a flow path is formed by bulging one of 1a and 1b from the surface.
[0020]
【The invention's effect】
As described above, according to the method for forming a container opening groove according to the present invention, a groove having an appropriate depth can always be formed at a predetermined position of a container. Further, it is not necessary to stop the transport of the container when forming the groove.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a vicinity of a flow path, taken along a direction in which a groove is formed, for describing an embodiment of the present invention.
FIG. 2 is a top perspective view of a container showing an example of the structure of the container to which the present invention can be applied.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Container 1a, 1b (made of resin) sheet 2 Flow path 2a Groove part 2b (for container opening) Recess C Forming area D of groove part along the irradiation direction by irradiation of each laser D made of individual resin forming flow path Sheet swelling amount E Range of groove formation F along the direction in which grooves are extended by laser irradiation F Total length L of grooves Laser

Claims (4)

Between the two bonded resin sheets, at least one of these resin sheets is a container having a channel formed by expanding from the surface of the container, on the surface of the expanded resin sheet, A method for forming a container opening groove for allowing the container to be easily opened by providing a groove along a direction crossing the flow path,
Irradiating the laser for forming the groove toward the surface of the swelled resin sheet, and irradiating the laser, the formation range of the groove along the irradiation direction is the same as that of the flow path at the portion where the flow path is formed. A method of forming a groove for opening a container, wherein the groove is larger than a swelling amount of a resin sheet. The method for forming a groove for opening a container according to claim 1, wherein the range of formation of the groove along the direction in which the groove is extended by the laser irradiation is equal to or longer than the entire length of the groove. The method of forming a groove for opening a container according to claim 1, wherein the laser irradiates the surface of the resin sheet via a galvano-polarizing lens. The said groove part is formed by irradiating the said laser toward the surface of each said resin-made sheet, without stopping conveyance of the said container during conveyance of the said container, The characterized by the above-mentioned. 4. The method for forming a groove for opening a container according to any one of claims 1, 2 and 3.

Images