TWI739433B - Plastic wire joining method and structure of container bag folding edge - Google Patents

Abstract

A plastic line joining method and structure for the hem of a container bag includes: laying a hem of a container bag on a metal solid surface; maintaining the solid surface at a condensation temperature through a cooling device; An injection needle of an injection machine performs a needle insertion action on a point of the folded edge, and solidifies and crystallizes at the bottom surface of the folded edge at the pinhole to form a base point; the injection needle performs a needle ejection action to make the molten plastic Filled in the pinhole, pressurized cold air is applied to make the molten plastic in the pinhole instantly cool and condense into a string; then, the injection needle or the flange is moved for a distance, and pressurized cold air is applied to condense the molten plastic Form a line bridge; repeat the above procedure to perform needle insertion, needle ejection, and translation at the next position of the hemming to form the next base point, line pillar, and line bridge; most base points, line pillars , And a continuous wire bridge along the folded edge to form a high-strength and low-elongation plastic wire bonding structure.

Description

Plastic wire joining method and structure of container bag folding edge

The present invention relates to a flexible transport packaging container. More specifically, it relates to a method and structure for folding and joining a container bag (or a space bag or a ton bag).

Container bag (or space bag, ton bag) is a kind of flexible transportation packaging container, which has the characteristics of large volume, light weight, and convenient loading and unloading. It can be transported by crane or forklift. It is widely used in bulk bulk at present. Transport packaging of materials.

The bulk bag is made of polypropylene (PP) as the main raw material. After adding a small amount of stable materials and uniformly mixing, the plastic film is melted and extruded by an extruder, cut into filaments, and then stretched, and then heat-set into high PP yarn with low strength and low elongation is made into bag cloth by weaving and laminating, and then stitched with sling and other accessories.

When the FIBC is produced and processed, the bag cloth needs to be folded and stitched to ensure the integrity and strength of the FIBC. As shown in Figure 1, the hemming stitching is carried out with a sewing machine using cotton thread. The reciprocating needle 1 of the sewing machine cooperates with the linear movement of the hemming of the bag fabric to sew one or more suture structures. The microscopic structure of the suture includes a pinhole 2, an upper thread 3 and a bottom thread 4 passing through the pinhole 2 and intersecting up and down, and an upper interlocking thread 5 and a lower interlocking thread 6 on the surface of the bag cloth.

Figure 1 further reveals the general situation of sewing, that is, the hole diameter of the needle hole is larger than the thread diameter of the cotton thread, so there is a gap between the needle hole and the cotton thread, which is easy to cause the problem of powder leakage in the container bag. The traditional solution to this problem The method is to install another leak-proof structure or install a leak-proof inner bag in the container bag, but increase the system Cheng’s troubles. In addition, pinholes cause puncture structural damage to the FIBC, but cotton thread cannot compensate for this damage, and the thicker the thread diameter, the larger the pinhole diameter, the stronger the degree of puncture damage, and the cotton thread and the pinhole are along the line Arranged in a straight line, a continuous and unstable structure is formed for the FIBC. Furthermore, when the container bag is loaded with heavy materials and suspended and carried, the pinhole will become larger and larger due to the weight of the bag body, which may cause damage. In addition, the cotton thread and the FIBC are different materials. When the FIBC is discarded and recycled, it is extremely difficult to remove the stitches. Therefore, the method of cutting off the hem is used, which causes the trouble of the recycling process.

In order to solve the above-mentioned problems, the present invention proposes a novel plastic wire bonding method and structure for the hemming of the container bag.

Technical features of the invention:

A plastic line joining method for the hemming of a container bag includes:

Step 1: Spread a folded edge of a container bag on a metal solid surface; maintain the solid surface at a condensation temperature through a cooling device;

Step two, an injection needle connected to an injection machine performs a needle insertion action on a point of the folded edge, and the needle insertion action causes the injection needle to pierce the folded edge to form a needle hole, and the injection needle starts from its tip The molten plastic is poured out, and the molten plastic immediately cools down when it contacts the solid surface, and solidifies and crystallizes at the pinhole on the bottom surface of the flange to form a base point; the range of the base point is greater than the diameter range of the pinhole;

Step 3: The injection needle performs a needle ejection action to escape the needle hole, and the needle ejection action is the reverse of the needle insertion action; while the needle ejection is activated, the needle tip continues to inject the molten plastic to make the molten plastic Is filled in the pinhole; at the same time, a pressurized cold air is applied from the upper surface of the flange To the hole needle; through the cooling effect of the pressurized cold air, the molten plastic filled in the pinhole instantly cools and condenses into a thread column, and the thread column, the hemming and the base point are all condensed into one body;

Step 4. The injection needle or the folded edge moves a distance in translation, while the needle tip continues to inject molten plastic on the upper surface of the folded edge while moving, the pressurized cold air is still continuously provided, so that the melted plastic instantaneously condenses into a bridge , The bridge and the upper surface of the flange are condensed into one body;

Step 5: Repeat steps 2 to 4, and perform the needle entry action of step 2, the needle ejection action of step 3, and the translation action of step 4 at the next position of the hemming to form the next base point, thread column, And wire bridge; a large number of base points, wire pillars, and continuous wire bridges form a high-strength, low-elongation plastic wire joint structure along the folded edge.

A plastic line joining structure for the hemming of a container bag, comprising:

One fold of a container bag;

Along the length of the folded edge, it is equidistantly condensed on several base points on the bottom surface of one of the folded edges;

Several thread pillars penetrated and condensed inside the flange, and a bottom end of the thread pillar and a base point are condensed into one body;

Several wire bridges are condensed on a top surface of the folded edge, wherein the two ends of each wire bridge are respectively condensed into one body with the tops of two adjacent wire posts.

Compared with the prior art, the advanced effects of the present invention are:

The method of the present invention condenses the molten plastic into the above-mentioned plastic wire joining structure and then joins the hemming of the container bag. The selected plastic is the same as that of the container bag. Therefore, the plastic wire joining structure has high strength and low elongation. The hemming can be joined together, and further integrated with the hemming, the tightness is greatly improved, and the plastic wire bonding structure will not be separated from the hemming, and its fixity can be maintained for a long time.

The base point, string column, and continuous string bridge make the plastic string joint structure stable in the hemming It is not easy to break. Even if a local break point occurs occasionally, it will not affect the overall fixation and tightness.

Although the aforementioned needle insertion action formed a pinhole in the flange, it was then filled with molten plastic and condensed into a thread column. The thread column was completely filled in the pinhole and tightly engaged with the flange contact surface. The thread column It completely compensates for pinholes and makes the plastic wire joint structure into a pinhole-free shape. When the container bag is loaded with powder, the problem of powder leakage from the plastic wire joint structure will not occur. When the container bag is deformed due to load-bearing and hanging load, the high-strength and low-elongation plastic-wire joint structure improves the structural strength of the hemming, and greatly reduces the probability of deformation or damage.

Because the plastic-wire joint structure and the container bag are made of the same material, when the container bag is discarded, all plastic can be recycled, reducing the trouble of the recycling process.

The method and structure of the present invention are not only applied to container bags, other plastic bags can also be joined by the method and structure of the present invention.

10: solid surface

11: Cooling device

20: Injection needle

21: Needle tip

22: Pressurized cold air

23: presser foot

30: Plastic wire bonding structure

31: base point

32: Line Column

33: line bridge

40: FIBC

41: Folding

[Figure 1] is a schematic diagram of the suture structure of a FIBC in the prior art.

[Figure 2] is a schematic view of the mechanism of the plastic thread suture structure of the container bag of the present invention.

[Figure 3] is one of the schematic diagrams of the action of the method of the present invention.

[Figure 4] is the second schematic diagram of the action of the method of the present invention.

[Figure 5] is the third schematic diagram of the action of the method of the present invention.

[Figure 6] is the fourth schematic diagram of the action of the method of the present invention.

[Figure 7] is the fifth schematic diagram of the action of the method of the present invention.

[Figure 8] is a schematic cross-sectional view of the plastic suture structure for the hem of the container bag of the present invention.

[Figure 9] is a schematic top view of the first embodiment of the plastic thread suture structure for the hemming of a container bag according to the present invention and a partial enlarged schematic view of the frame selection.

[Figure 10] is a schematic top view and a partial enlarged schematic view of the frame selection of the second embodiment of the plastic thread suture structure for the hemming of the container bag of the present invention.

In order to facilitate the description of the central idea of the present invention expressed in the column of the above-mentioned summary of the invention, specific embodiments are used to express it. The various objects in the embodiments are drawn according to the scale, size, deformation or displacement suitable for illustration, rather than drawn according to the actual component ratio. Elements with the same and symmetrical configuration are denoted by the same number. The drawings are only to facilitate the description of the method of the present invention, and do not indicate or imply that the shape, structure or orientation of the device or element referred to has specific limitations, and therefore cannot be understood as a limitation of the present invention.

The plastic line joining method of the folding edge 41 of the container bag 40 of the present invention includes:

Step one (as shown in Figure 2), flatly spread a folded edge 41 of a container bag 40 on a metal solid surface 10; maintain the solid surface 10 at a condensation temperature by a cooling device 11, and the range of the condensation temperature is 5°C to 20°C, preferably 5°C.

Step two (as shown in Figure 3), an injection needle 20 connected to the injection machine performs a needle insertion action on a point of the folded edge 41, and the needle insertion action causes the injection needle 20 to pierce the folded edge 41 to form a needle Hole; Through the extrusion process of the injection machine, the injection needle 20 continuously and uninterruptedly injects the molten plastic from its needle tip 21, the molten plastic is at the melting point temperature (up to 160 ℃ -190 ℃), contacting the low temperature of the solid surface 10 It is rapidly cooled in an instant, and the bottom surface of the flange 41 is solidified and crystallized at the pinhole to form a base point 31. The aforementioned molten plastic is the same as the plastic used to make the container bag 40, including but not limited to polypropylene (PP), high density polyethylene plastic (High Density Polyethylene, referred to as HDPE). The melting point temperature of PP is 165°C, and that of HDPE is 125°C to 135°C. Based on the same material selection, the base point 31 and the bottom surface of the flange 41 will be condensed into one body, but will not be fixed on the metal solid surface 10.

Step three (as shown in Figure 4), the injection needle 20 performs a needle ejection action to escape the needle hole; while the needle is ejected, the needle tip 21 continues to inject molten plastic, so that the molten plastic fills the pinhole; at the same time, Pressurized cold air 22 is applied to the needle from the upper surface of the flange 41, and the temperature of the pressurized cold air 22 is 5°C to 20°C; through the cooling effect of the pressurized cold air 22, the molten plastic filled in the pinhole The instant cooling and condensing form a thread post 32, the contact surface of the thread post 32 and the folded edge 41 and the base point 31 are all condensed into one body. Based on the movement of the needle and the injection pressure, microscopically the contact surface of the thread post 32 and the folded edge 41 is condensed into a rough burr shape. The thread post 32 is completely filled in the pinhole and closely connected to the contact surface of the folded edge 41. Close, so the pinhole is completely free of gaps.

Step 4 (as shown in FIG. 5), the injection needle 20 is moved in translation, moving a distance parallel to the upper surface of the flange 41. This action can also be replaced by the movement of the flange 41. Preferably, the distance is greater than the range of the base point 31, specifically, it can be 2 to 3 times the diameter of the injection needle 20, and the specific data range of the distance is 1 mm to 3 mm. The moving distance can be adjusted according to actual needs, and the present invention is not limited to the specific data or ratio provided. While moving, the needle tip 21 continues to inject molten plastic, and the pressurized cold air 22 is still continuously provided, so that the molten plastic instantaneously condenses into a bridge 33, and the bridge 33 and the upper surface of the flange 41 are condensed into one body.

Step 5 (as shown in Figures 6, 7, 8), repeat steps 2 to 4, and perform the needle insertion action of step 2, the needle ejection action of step 3, and the translation action of step 4 at the next position of the folded edge 41. Accordingly, the next base point 31, the line post 32, and the line bridge 33 are formed. A plurality of base points 31, wire posts 32, and continuous wire bridges 33 form a high-strength and low-elongation plastic wire bonding structure 30 along the folded edge 41.

In terms of technical details:

The speed of the needle insertion and needle ejection action needs to be determined according to the thickness of the hemming 41 of the container bag 40. The specific action time of the needle insertion and needle ejection reciprocating once ranges from 0.1 second to 1 second. In principle, the hemming 41 The thicker the thickness, the slower the speed; for example, for the hemming 41 with a thickness of 1mm, the speed of the needle in and out is set to 0.1 second.

The mass flow rate of the molten plastic through the needle tip 21 is 10kg/h-20kg/h. In principle, the slower the needle entry and exit speed, the lower the mass flow rate.

The metal solid surface 10 is preferably a stainless steel plate. The method of maintaining its condensation temperature includes, but is not limited to, water-cooled and electric-cooled.

The position of the fold 41 where the plastic thread is stitched should be pressed by the presser foot 23 to keep it flat and not to move due to the influence of the injection needle 20.

The injection needle 20 pierces the folded edge 41 with its needle tip 21, and the needle tip 21 has a taper. Therefore, the pinholes and thread pillars 32 formed inside the folded edge 41 may also be tapered in a microscopic view.

Preferably, the pressurized cold air 22 should follow the displacement of the injection needle 20.

As shown in FIG. 9, the plastic wire joining structure 30 formed by performing the above-mentioned steps with a single needle is a single straight line type.

As shown in Fig. 10, several needle heads perform the above steps at the same time, or the plastic wire joint structure 30 formed by the reciprocation of a single needle head sequence is a multi-linear type. Preferably, the base point 31 and the wire post 32 of one plastic wire bonding structure 30 are adjacently corresponding to the wire bridge 33 of the other plastic wire bonding structure 30.

In the present invention, the above method can be achieved by the reciprocating movement of the injection needle 20 relative to the flange 41, and the opposite changes can be made accordingly. The same can be achieved by the reciprocating movement of the solid surface 10 and the flange 41 relative to the injection needle 20 Effect.

30: Plastic wire bonding structure

31: base point

32: Line Column

33: line bridge

41: Folding

Claims (10)

A plastic line joining method for the hemming of a container bag includes: Step 1: Spread a folded edge of a container bag on a metal solid surface; maintain the solid surface at a condensation temperature through a cooling device; Step two, an injection needle connected to an injection machine performs a needle insertion action on a point of the folded edge, and the needle insertion action causes the injection needle to pierce the folded edge to form a needle hole, and the injection needle starts from its tip The molten plastic is poured out, and the molten plastic immediately cools down when it contacts the solid surface, and solidifies and crystallizes at the pinhole on the bottom surface of the flange to form a base point; the range of the base point is greater than the diameter range of the pinhole; Step 3: The injection needle performs a needle ejection action to escape the needle hole, and the needle ejection action is the reverse of the needle insertion action; while the needle ejection is activated, the needle tip continues to inject the molten plastic to make the molten plastic Filled in the pinhole; at the same time, a pressurized cold air is applied from the upper surface of the flange to the hole needle; through the cooling effect of the pressurized cold air, the molten plastic filled in the pinhole is instantly cooled and condensed into a thread column , The line column, the hemming and the base point are all condensed into one body; Step 4. The injection needle or the folded edge moves a distance in translation, while the needle tip continues to inject molten plastic on the upper surface of the folded edge while moving, the pressurized cold air is still continuously provided, so that the melted plastic instantaneously condenses into a bridge , The bridge and the upper surface of the flange are condensed into one body; Step 5: Repeat steps 2 to 4, and perform the needle entry action of step 2, the needle ejection action of step 3, and the translation action of step 4 at the next position of the hemming to form the next base point, thread column, And wire bridge; a large number of base points, wire pillars, and continuous wire bridges form a high-strength, low-elongation plastic wire joint structure along the folded edge. The plastic line joining method for the hemming of the container bag according to claim 1, wherein the condensing temperature The range of degrees is 5°C to 20°C. The plastic wire joining method for the hemming of the container bag according to claim 1, wherein the molten plastic is the same as the plastic used to make the container bag. The plastic wire bonding method for the hemming of the container bag according to claim 1, wherein the temperature of the pressurized cold air is in the range of 5°C to 20°C. The plastic line joining method for the hemming of the container bag as described in claim 1, wherein the distance is 1mm~3mm. The plastic thread joining method for the hemming of the container bag according to claim 1, wherein the mass flow rate of the molten plastic through the needle tip is 10kg/h-20kg/h. A plastic line joining structure for the hemming of a container bag, comprising: One fold of a container bag; Along the length of the folded edge, it is equidistantly condensed on several base points on the bottom surface of one of the folded edges; Several thread pillars penetrated and condensed inside the flange, and a bottom end of the thread pillar and a base point are condensed into one body; Several wire bridges are condensed on a top surface of the folded edge, wherein the two ends of each wire bridge are respectively condensed into one body with the tops of two adjacent wire posts. According to claim 7, the plastic thread joining structure for the hemming of the container bag, wherein the plastic thread joining structure is a single straight line type. The plastic-line joining structure for the hemming of the container bag according to claim 7, wherein the plastic joining structure is a multi-linear type. According to claim 9 of the plastic thread joining structure for the hemming of the container bag, wherein the base point and the string post of one plastic thread joining structure are adjacently corresponding to the bridge of the other plastic thread joining structure.

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