JPS5985739A - Manufacture of square bottom bag made of synthetic resin - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to a method for manufacturing square bottom bags made of synthetic resin, and furthermore, a method for continuously manufacturing square bottom bags made of synthetic resin with a square bottom formed in advance. - related to.

Synthetic + fat (plastic film) bags are water resistant,
They are superior to paper bags in terms of mechanical strength, surface gloss, etc., and are therefore used for a wide range of purposes. However, bags made of synthetic resin have poor self-reliance because they are so-called weak, and the stability when placed on the bag after storing articles is also not sufficient.

In order to improve this point, a square-bottomed bag has already been proposed in which a reinforcing welded part consisting of a rectangular heat-welded line is attached to the bottom of the bag to increase the surface strength of the square bottom and improve its self-reliance.

The conventional manufacturing method for such square-bottomed bags involves cutting a gusseted flat commercial film into a predetermined length, folding the cut ends together to form a bag body, and attaching the body to the bag body. A core having a plate of the same shape as the corner bottom at the tip is completely opened by a board, etc., and inserted into the bag, and the film constituting the corner bottom is hot-pressed between it and a heater installed outside the bag. There was a method in which the reinforcing welded part was formed by
issue).

However, when using this method, it is difficult to insert the core because it is necessary to fully open the opening of the bag in order to insert the core, and it is difficult to reliably produce a square-bottomed bag. Furthermore, as the core is inserted into the bag, the gusseted folds of the bag disappear and break off, making it difficult to fold the square bottom bag after forming the square bottom bag. It was difficult to stock up.

The purpose of the present brother is to be able to manufacture square bottom bags as well as to
To provide a method for manufacturing square bottom bags, which allows easy manufacturing of river bottom bags one after another in a folded state.

The present invention consists of an opening process for half-opening the opening of a bag made of a gusset-folded flat cylindrical film with a shear length and a bottom stone piece formed by welding one end edge; A pair of expansion plates at the tip! A core insertion step in which the expanded core is inserted with the expansion plate folded in the insertion direction, and a pair of bag bodies are inserted in a position that does not interfere with the expansion operation of the expansion plate into the bottom of the bag body. a bottom bulging step in which the bag body is held in the width direction from both sides by a holding body and a gas such as air is blown into the bottom side of the bag body to carve the bottom side of the bag body;
Pressing a heater so as to sandwich the corner bottom between the expanded expansion plate and the expanded expansion plate. The above object is achieved by providing a corner bottom welding step in which a reinforcing weld is formed at the corner bottom, and a extraction step in which the rear and front self-expanding plates are folded and the core is extracted after the corner bottom construction begins. Trying to-
It is something that

Embodiments of the present invention will be described below based on the drawings.

Figure 1 schematically shows the overall configuration of a manufacturing apparatus to which an embodiment of the method for manufacturing synthetic resin square eight bags according to the present invention is applied. The film 2 is wound in many layers. The flat cylindrical film 2 is made of synthetic resin in general, and is preferably made of soft synthetic resin such as polyethylene or polyethylene blue. It is selected by many cities. Ichitsune is grown at a culm degree of 10 μn to 200 rn.

The flat cylindrical film 2 fed from the original film 1 is suspended between a pair of presser plates 5 via transfer rollers 3 and 4 consisting of a pair of roller bodies. The holding plates 5 are disposed opposite to each other so as to sandwich the film 2 in the width direction from both sides of the flat cylindrical film 20, and are attached via biasing means to a reciprocating member that moves forward and backward toward the film 2 from both sides of the film 20. It's leaking.

The ivy 7 is caused by the lower part of the presser plate 5 of the advancing/retracting member 6 in the figure.
The cutter 70 is further provided with a heat exchanger 8 on the lower near side, and when the reciprocating member 6 is in the state of moving forward and retracting toward the film 2 and sandwiching the film 2 from both sides, the film is It is fixed by two pressers 5, cut in the width direction by a cutter 7, and welded in the width direction by a heat sealer 8. That is, here a bag body 12 is formed, which is made of the gusseted flat cylindrical film 2 of a predetermined length with one end welded and a bottom welded portion 11 formed therein.

A vacuum roller 21 located on one side of the advancing/retracting member 6 and pinching the film 2 from both sides is arranged in parallel. As shown in FIGS. 2 and 3, these vacuum rollers 21 are connected to a suction tube 23, which is a cylindrical-center-beam cylindrical body, which is connected to a suction tube (not shown) via a suction tube 22, and this suction section. 23 and a rotating rubber tube 24 which is rotatably fitted into the rubber tube 23 and rotated by a rotation drive mechanism (not shown). A suction slit 25 of a predetermined width is provided along the longitudinal direction on the side surface of the suction cylinder 23 facing the fill L2 side, while a large number of suction holes 26 are provided along the entire circumference of the rotary rubber tube 24. and the suction slit 25
The cylindrical film 2 is placed in the suction hole 26 that rotates thereon, and the cylindrical film 2 is configured to be transferred in the direction of rotation of the N-rolled rubber cylinder 24.

The gap between the vacuum rollers 21 that sandwich the cylindrical film 2 from both sides is gradually widened toward the lower stage in FIG. Both sides are sucked by the vacuum roller 21 located in the position, and the vacuum is lifted! The cylindrical film 2
The core 3 is left in a half-open state, and is transported vertically downward in the figure to the tsukuda in the half-open state.
1 is inserted. In fact, a plurality of cores 31 are arranged radially along the circumferential direction of the rotating machine 32, and these plurality of cores 31 are connected to the rotating machine 32. It is configured to be sequentially rotated about 32 in the counterclockwise direction in FIG. 1.

A pair of expansion plates 33 are provided on the front end side of the core 31, as shown in FIGS. 4 and 5.

These expansion plates 33 are each mounted on a plate-shaped mount 35 via a rotation shaft 34 so that they can be rotated for several days with one end edge as the center of rotation. Further, each expansion plate 33 has a substantially trapezoidal plate shape with a long rotating end edge, while the mounting base 35 has a base end side or a tip end of a mounting handle 36 attached to the rotation mechanism 32. It is attached to the section.

The drive mechanism for the expansion plate 33 is, for example, as shown in FIG.
1, an intermediate pulley 42 located at an intermediate portion of the pair of expansion plates 33, a drive pulley 44 that is identified by the rotation axis of the driven gear 43 and rotates in synchronization with the driven gear 43, a direction change pulley 45, and these pulleys. 41, 42, 44, and 45 are provided with a wire 46 in the shape of a hearth, and a driving gear 47 that is rotated and driven by a drive source such as a motor is meshed with the driven wheel 43. In addition, there is bamboo in which the drive mechanisms for the pair of expansion plates 33 are arranged symmetrically with respect to each other.

According to the drive mechanism configured in this manner, the pair of expansion plates 33 are expanded and driven by appropriately driving the driving shaft 47 in reverse. Note that, as shown in FIG. 7, a timing pulley 51 is used instead of the rotation pulley 41.
In addition, a timing belt 52 may be used instead of the wire 46. When such timing pulleys 51 and 52 are used, there is no sliding friction and the operation during reversal is reliable, but when the wire 46 is used, the drive mechanism as a whole becomes smaller.

After inserting the core 31 into the opening of the bag 12 which is in the half-opened state in this manner and carrying out two core insertion steps, the bag body I2 of the expansion plate 33 is inserted as shown in FIG. To the extent that it does not interfere with the expansion movement at the bottom? At this time, the bag body 12 is held between both sides in the width direction by a pinching body 61 consisting of a pair of rollers, etc., and pneumatic gas is blown into the bottom side of the bag body 12 from a blowing mechanism (not shown) to form the wrinkled bottom part of the bag body 12. A bottom bulging process is performed to bulge the sides.

Next, the expansion plate 33 is expanded within the inflated bottom bag 12 to the state shown in FIG. 5 to form a square bottom portion 71. Here, a corner bottom forming step will be performed.

A heater 72 is pressed against the corner bottom portion 71 so as to sandwich the corner bottom portion 71 between the corner bottom portion 71 and the expansion plate 33 .

As shown in FIG. 8, the heater 72 has a suppressing surface made of a non-adhesive material such as a silicon plate, and a ribbon heater 73 made of a nichrome wire or the like is embedded in an irregular shape. is pressed against the corner bottom 71,
A reinforcing melted part having the same shape as the Rihon heater 73 is formed on the corner bottom part 71. At this point, a square bottom welding process is performed to form a supplementary welded part on the square bottom 71 of the bag body 12, thereby forming a square bottom bag 81.

The square bottom bag 81 formed by the door welding process is placed on top of the core 31 and subjected to a core welding process.

During this gap, the expanding plate 33 of the core 31 is folded as shown in FIG. It will never disappear. Also, when removing the core 31, turn the pair of rotating pieces 82, each of which is in contact with the back side of both end edges of the square bottom 71! By operating, the square bag 8 is formed from the core 31.
1 will be selected as a strong objective. During the removal process by these rotating pieces 82, one end edge side of the front bottom portion 71 is removed from being clamped by the clamping portion +83 consisting of a pair of clamping roller tongues! At the same time, the one end edge side is pulled out and moved in the direction, and the stopper 84 is brought into contact with the other end edge side of the square bottom part 71, and as the square bottom part 71 is pulled out by the clamping part 83, the square bottom part 71 is sequentially folded. Let it fold up. In this way, with the corner bottom 71 folded, the core 3
The square bottom bag 81 that has been completely pulled out from the stock mechanism 8
5 will be stocked sequentially.

According to this embodiment, when the core 31 is inserted into the bag body 12, the opening of the bag body 12 is not fully opened, and when the core 31 is removed from the formed square bottom bag 81, Since the frontage portion is not fully opened, the creases formed in advance on the square bottom bag 81 and gusset folded will not disappear during the manufacturing process of the square bottom bag 81. Therefore, it is easy to sequentially stock the square bottom bags 81 with the square bottom portions 71 folded. Furthermore, when pulling out the core 31 from the bag 81 toward the corner, the corner bottom portion 71 is bent by the stopper 84 during the pulling operation, which is extremely convenient.

In addition, since the expansion plate 33 of the core 31 is inserted into the bag 12 which is in a half-open state with the expansion plate 33 folded, the opening of the bag 12 must be fully opened to allow the core 31 to be inserted into the bag 12. Unlike the case where the core 31 cannot be inserted into the bag body 12, the core 31 can be inserted securely into the bag body 12. Therefore, the square bottom bag 8
1 can be reliably manufactured continuously.

When the expansion plate 33 is expanded, the bottom side of the bag body 12 is expanded by closed air, etc., so that wrinkles etc. do not occur in the bag body 12 when the expansion plate 33 is expanded. ,
From this point of view as well, the square bottom bag 81 can be formed reliably, and the square bottom bag 81 can be made clean without wrinkles or the like.

Furthermore, the bag body 12 (flat cylindrical film 2) is transferred to the core 31 side by the vacuum roller 21 and simultaneously expanded to a half-open state. There is no need to separately provide an opening process and a transfer process, and the manufacturing process of the square bottom bag 81 is simple.

In this case, instead of using the vacuum roller 21, as shown in FIG. Generally U-shaped opening members 91 are attached at all times, and these opening members 91 are moved forward and backward in the expansion direction (in the direction of the arrow in the figure), thereby expanding the cylindrical film 2 by a predetermined amount and opening the opening. There are four approximately boat-shaped openings 92 inserted into the folded portions of the gusset-folded flat cylindrical film 2 on the feed direction side of the section 41, and four openings on the image side of the cylindrical film 2. The rollers 93 are brought into contact with each other, and the aperture body 52 and the aperture rollers 93 transport the cylindrical film 2 downward in FIG. (-=12) may be twisted into a half-open shape. At this time, the opening roller 93
As shown in FIG. 10, a spiral protrusion Φ94 of a predetermined shape is formed on the surface of the cylindrical film, which is fed toward the - side in FIG. 9 by these protrusions 94. Both sides of 2 are pressed and rubbed by the protruding strips 94 and expanded in the width direction. In other words, both sides are configured to be expanded without wrinkles or the like.

Furthermore, can the cylindrical film 2 (bag body 12) be opened? In order to bring the film 2 into a half-open state, the film 2 may be expanded by blowing P air or the like into the film 2 from the core 31 side.

Further, the corner bottom portion 71 is formed in the shape of a ribbon heater 73 shown in FIG. 8. The shape is not limited to the shape shown in FIG. 8, but may be a simple rectangular shape, for example, and any shape that can improve the shape retention of the corner bottom portion 71 is sufficient.

As described above, according to the present invention, it is possible to provide a manufacturing method with a square bottom ≧ that can reliably manufacture a square bottom bag and also easily manufacture the square bottom bag in a folded state for the next generation.

[Brief explanation of the drawing]

Figure 1 is a front view showing the overall configuration of a manufacturing device to which an embodiment of the method for manufacturing a square bottom bag made of synthetic resin according to the present invention is applied;
Figure 2 + of the bayou roller used in the above embodiment
FIG. 3 is an enlarged perspective view showing the structure with a part cut away; FIG. 3 is a sectional view taken along line III-III in FIG. 2; FIGS.
The figures are an enlarged perspective view clearly showing the hem of the core used in the above-mentioned embodiment in different operating states, FIG. 6 is a front view showing -+ of the drive mechanism of the expansion plate, and FIG. 7 8 is a front view showing another main part of the drive mechanism, FIG. 8 is an enlarged dog birth diagram showing the pressing surface of the heater used in the embodiment, /9! 10 is a perspective view showing the main parts of an embodiment other than the above, and FIG.
It is an enlarged view of the frontage without showing the surface shape of each frontage shown in the figure. 2... Casette folded flat cylindrical film, 7... Cutter, 8... Heat sealer, 11... Bottom adhesion resistant part, 1
2...Bag body, 21...Vacuum roller, 31...
- Core, 32... Rotating mechanism, 33... Expansion plate, 34
... Rotation shaft, 41 ... Rotation pulley, 46 ... Wire, 51 ... Quimming pulley, 52 ... Timing belt, 61 ... Pincer body, 71 ... Corner section , 72・
... Heater, 73 ... Ribbon heater, 31 ... Square bottom bag, 82 ... Rotating piece, 83 ... Holding member, 84 ...
Stopper, 85...Stock mechanism, 91...Opening part, 92...Opening body, 93...Opening 0-ra.

Claims (1)

[Claims] (1) Opening step of half-opening the opening of a ζ body made of a gusset-folded flat cylindrical filter of a predetermined width with one end edge glued and the end welded part ripened, and the opening in the half-open state. A core insertion step of inserting a core provided with a pair of expansion plates from the part to the tip ψ in a circle in which the expansion plates are folded in the insertion direction;
To the extent that the expansion plate does not interfere with the expansion operation at the bottom of the bag body.
The smell is removed from the art dealer in the width direction by the gripping body of the bag.
a bottom expansion step of blowing gas into the bottom side of the bag to inflate the bottom side of the bag; and expanding the expansion plate in the shaped bottom side of the bag to open the square bottom. The corner bottom forming process involves forming a reinforcing weld on the C corner bottom by pressing the heater so as to sandwich the corner bottom between the expanded expansion plates, and the corner bottom welding process. A method for making a synthetic resin square bottom part, comprising a core extraction step of folding the expansion plate and extracting a core after the shank step.