JPH0147295B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for thermally bonding plastic films, and more particularly to an improved apparatus for overlapping and thermally bonding plastic films.

Some plastic films have mechanical strength,
There are films with excellent transparency, oil resistance, weather resistance, gas barrier properties, etc., and by taking advantage of these properties, various films are used in the daily necessities, industrial, medical, and other fields.
It is widely used in many fields such as agricultural fields. When these plastic films are actually used, they are processed into bags, cylinders, etc.
Processing to widen the width is also often performed.

Conventionally, heat sealing, impulse sealing, ultrasonic sealing, high frequency sealing, and the like are known as methods for adhesively sealing plastic films and the like. The adhesive method is selected depending on the type of plastic in the plastic film and the intended use of the article to be adhered. Recently, in order to improve the performance of plastic film, a film has been formed on the surface.
Techniques such as multi-layering began to be adopted,
A problem with such a film was that it was difficult to adhere.

In order to solve such problems,
Publication No. 19341, Special Publication No. 16546, Special Publication No. 1972-16546, Special Publication No. 16546
An adhesive device described in Publication No. 13318 has been proposed and put into practical use. However, there has been a problem in that the strength of the bonded surfaces bonded by these devices is not necessarily sufficient.

When bonding plastic films, depending on the use of the bonded material, bonded portions may be formed in dots at regular intervals. However, with conventionally proposed devices, it has been difficult to form dotted adhesive portions at regular intervals.

In such a situation, the present inventors have found that not only general plastic film but also plastic film with a special film formed on the surface can be easily used.
The present invention has been completed as a result of intensive studies aimed at providing a thermal bonding device that can form bonded parts continuously or in dots at regular intervals.

Therefore, the gist of the present invention is to provide an apparatus for thermally bonding a plurality of plastic films by stacking them between a pair of plastic film transfer endless belt mechanisms disposed opposite each other, and transferring the plastic films. The first endless belt mechanism has two drive rolls on which the endless belt is stretched rotatably supported, and a drive means for driving the endless belt on the shafts of the two drive rolls. The second endless belt mechanism is rotatably supported by two rolls on which the endless belt is stretched, and the two rolls are rotatably supported on the second endless belt mechanism, and the rolls are integrally moved toward and from the first endless belt mechanism.
provided with means for separating, and
A heating block and a cooling block are provided in a portion surrounded by the endless belt of each endless belt mechanism, and a heating block and a cooling block are provided at positions facing each other via each endless belt, and a heating block and a cooling block are provided in a portion surrounded by the endless belt of each endless belt mechanism. The heating block is further provided with means for approaching and separating from the heating block of the first endless belt mechanism from the side of the second endless belt mechanism support block. It resides in the adhesive device.

Hereinafter, the present invention will be explained in detail based on the drawings, but the present invention is not limited to the following examples unless it exceeds the gist thereof.

The figure shows an example of a thermal bonding device according to the present invention,
FIG. 1 is a schematic side view of the main parts of the device, FIG. 2 is a schematic cross-sectional view taken along the line --- in FIG. 1, and FIG. 3 is a schematic cross-sectional view taken along the line --- in FIG.

In the figure, 1 is a first endless belt mechanism, 2 is a second endless belt mechanism, 3 is a table, 4 and 5 are drive rolls of the first endless belt mechanism, 6 is an endless belt, 7 is a motor, 8, 9 is a pulley, 10 is a belt, 11 is a heating block, 12 is a heater,
13 is a heating block support, 14 is a bolt, 15
16 is the first endless belt mechanism support block; 17 is the shaft of the roll 4; 18 is the fixing bolt of the heating block support 13; 19 is the cooling block;
0 indicates a cooling block support, 21 indicates a bolt, and 22 indicates an air conduit to the cooling block.

23 is a second endless belt mechanism support block;
4 and 25 are rolls of the second endless belt mechanism; 26
31 is the heating block, 32 is the heater, 33 is the heating block guide body, 34 is the bolt, 35 is the piston rod, 36 is the thermocouple of the heating block, 37 is the shaft of the roll 24, 38 is the heating block guide body 33 , 39 is the cooling block, 40 is the cooling block support, 41 is the bolt, 42 is the air conductor to the cooling block, 43, 4
7 is a fluid pressure cylinder, 44, 45, 48, 49
5 is a solenoid valve, 46 and 50 are conduits for compressed fluid, 51 is an instrument panel, 52 is a support arm, 53 is a plastic film end guide piece, 54 and 55 are grooves, 56 and 57
indicate plastic films.

The thermal bonding device according to the present invention is provided with a pair of endless belt mechanisms facing each other. These endless belt mechanisms have the function of transporting the plastic film to be thermally bonded between the two endless belts, and thermally bonding the plastic film to a desired location while the film is being transported. Although the pair of endless belt mechanisms are arranged one above the other in the figure, it goes without saying that the arrangement is not limited to this example.

In the first endless belt mechanism 1 of the pair of endless belt mechanisms described above, two drive rolls 4 and 5 on which an endless belt 6 is stretched are rotatably mounted on a first endless belt support block 16. It is pivoted. The first endless belt support block 16 is fixed to, for example, the table 3 so as not to move.

The two drive rolls 4 and 5 function to drive an endless belt 6 stretched between both rolls. The center axes of both rolls are preferably arranged in parallel. The distance between the center axes of both rolls can be appropriately selected depending on the type and thickness of the plastic film to be thermally bonded. The drive rolls 4, 5 can be made from materials such as rubber, metal, plastic, wood, etc., but are preferably made from a metal material. The lengths, diameters, etc. of the drive rolls 4, 5 can also be appropriately selected depending on the type, thickness, etc. of the plastic film to be thermally bonded.

Endless belt 6 stretched between drive rolls 4 and 5
The plastic film to be hot glued,
Endless belt 2 provided in the second endless belt mechanism
Together with 6, it functions to pinch and transfer. The width of the endless belt 6 is preferably approximately the same as the length of the drive rolls 4 and 5. It is best to choose the material of the endless belt from metal, plastic, etc.
Among these, those prepared from heat-resistant plastics such as silicone resins and fluorine resins are preferred.

The drive rolls 4 and 5 on which the endless belt 6 of the first endless belt mechanism is stretched are provided with a drive means for driving the drive rolls 4 and 5. The figure shows an example in which a pulley 8 is provided at the tip of the roll shaft 17 of the roll 4, and a belt 10 is stretched between the pulley 8 and a pulley 9 provided on the motor 7. It is also possible to have a structure in which the belt 10 is stretched around pulleys provided on both the rolls 4 and 5 and interlocked with each other.

The first endless belt mechanism 1 is provided with a heating block and a cooling block in a portion surrounded by the endless belt 6.

The heating block 11 is heated by a heater, and this heat is passed through the endless belt 6 to heat the bonding location of the plastic film to be thermally bonded. Therefore, it is preferable to embed a heater 12 in the heating block 11. In addition, in order to bring the heating block 11 into contact with the side of the endless belt 6 that heats the plastic film to be thermally bonded, the heating block support 13 is attached to the first endless belt mechanism support block 16 by means of bolts 18. Fix this heating block support 1
3 and the heating block 11 are preferably guided by bolts 14 and biased against the inner surface of the endless belt 6 by springs 15.

Both the heating block 11 and the heating block 13 that supports it are made large enough to be accommodated in the area surrounded by the endless belt 6, as shown in FIG. The width of the heating block 11 is preferably equal to or slightly narrower than the width of the endless belt 6. The material of the heating block 11 is preferably a metal material.

The cooling block 19 is a heated endless belt 6.
It is provided for the purpose of cooling. Cooling is most effectively achieved by blowing air. The cooling block 19 is made of a metal material with high thermal conductivity and has a hollow interior so that air directed through an air conduit 22 to the cooling block is blown onto the inner surface of the endless belt 6. In order to do this, the first endless belt mechanism support block 1
6, the cooling block support 2 is secured by bolts 18.
0 is fixed, and the cooling block support 20 and cooling block 19 are preferably guided by bolts 21 and biased against the inner surface of the endless belt 6 by a spring.

Both the cooling block 19 and the cooling block support 20 supporting it are of such a size that they can be accommodated in the area surrounded by the endless belt 6 together with the heating block 11, as shown in FIG.
The width of the cooling block 19 is preferably slightly narrower than the width of the endless belt 6 and the same or slightly narrower than the width of the heating block 11.

When fixing the first endless belt mechanism 1 to the table 3, it is preferable to fix it so that the surface of the endless belt 6 forms the same surface as the surface of the table 3.

In the second endless belt mechanism 2 provided opposite to the first endless belt mechanism 1, first, two rolls 24 and 25 on which an endless belt 26 is stretched are attached to the second endless belt mechanism support block 23. Each is rotatably supported on a shaft. FIG. 2 shows an example in which the roll 24 is pivotally supported on the second endless belt mechanism support block 23 by a roll shaft 37. The roll 25 is similarly supported by the roll shaft. These two rolls 24 and 25 function to stretch the endless belt 26. Both rolls are arranged so that their central axes are parallel, and also parallel to the central axes of the rolls of the first endless belt mechanisms 4 and 5. As shown in FIG. 1, the roll 24 is connected to the roll 4 and the roll 2.
5 are respectively opposed to the roll 5.

The rolls 24, 25 can be made from materials such as rubber, metal, plastic, wood, etc., but are preferably made from a metal material. roll 24,
The length, diameter, etc. of the rollers 25 are preferably the same as those of the drive rolls 4 and 5.

Endless belt 26 stretched between rolls 24 and 25
The plastic film to be hot glued,
Endless belt 6 provided in the first endless belt mechanism
It also functions to pinch and transport the material. The width of the endless belt 26 is preferably the same as the width of the endless belt 6, and the material thereof is also preferably the same as that of the endless belt 6.

The second endless belt mechanism 2 includes an endless belt 26
A heating block and a cooling block are provided in the area surrounded by. The heating block 31 is heated by a heater, and this heat is passed through the endless belt 26 to heat the bonding location of the plastic film to be thermally bonded. For this reason, it is preferable to embed a heater 32 in the heating block 31. Furthermore, in order to bring the heating block 31 into contact with the side of the endless belt 26 that heats the plastic film to be thermally bonded, the heating block guide body 33 is attached to the second endless belt mechanism support block 23 by means of bolts 38. Fix and bolt 3
It is preferable to have a structure in which the piston rod 35 urges the inner surface of the endless belt 26 while guiding the endless belt 26 with the piston rod 35.

Both the heating block 31 and the heating block guide body 33 that guide it are made large enough to be accommodated in the area surrounded by the endless belt 26, as shown in FIG. The width of the heating block 31 is preferably the same as the width of the heating block 11 provided in the first endless belt mechanism, and as shown in FIG.
Provided at a position opposite to 1.

The heating block 31 is preferably made of metal. Preferably, the heating block 31 is equipped with a thermocouple 36 so that the temperature can be automatically adjusted.

The cooling block 39 is a heated endless belt 2.
It is provided for the purpose of cooling 6. Cooling is most effectively achieved by blowing air. The cooling block 39 is made of a metal material with high thermal conductivity, has a hollowed out interior, and directs air to the cooling block through an air conduit 42 to the endless belt 26.
Make sure to spray it on the inside surface. To do this, the cooling block support 4 is attached to the second endless belt mechanism support block 23 by means of bolts.
0 is fixed, and the cooling block support 40 and the cooling block 39 are preferably guided by bolts 41 and biased against the inner surface of the endless belt 26 by a spring. Both the cooling block 39 and the cooling block support 40 supporting it are of such a size that they can be accommodated together with the heating block 31 in the area surrounded by the endless belt 26, as shown in FIG. It is preferable that the width of the cooling block 39 is slightly narrower than the width of the endless belt 26.

The plastic film thermal bonding apparatus according to the present invention is provided with means for integrally moving the second endless belt mechanism toward and away from the first endless belt mechanism.

The figure shows the second endless belt mechanism support block 2.
3 is connected to a fluid pressure cylinder 43, and the fluid pressure cylinder 43 is supported by a support arm 52.
The fluid pressure cylinder 43 is fixed to the support arm 52, and the pressure of the fluid supplied to the fluid pressure conduit 46 is controlled by the solenoid valve 4.
4 and 45, the piston fitted into the hydraulic cylinder 43 is slid, and the second endless belt mechanism support block 23 can be moved upward or downward in the figure. The second endless belt mechanism support block 23 incorporates the rolls 24, 25, the heating block 31, and the cooling block 39, so when the second endless belt mechanism support block 23 is moved, Everything that is there moves as one. In order to move the second endless belt mechanism support block 23 closer to and away from the first endless belt mechanism, it is preferable to use a fluid pressure cylinder, but the method is not limited to this method, and a toggle method or other method may be used. It is also possible to adopt this method.

The heating block 31 provided in the second endless belt mechanism 2 is provided with means for approaching and separating from the heating block 11 provided in the first endless belt mechanism.

In the figure, the end of the heating block 31 is fixed to the tip of a piston rod 35 so as to have an L-shaped cross section, and the piston rod 35 passes through a hole provided in the heating block guide body 33 and connects to the endless belt mechanism support block. An example is shown in which the piston is slidably inserted into a fluid pressure cylinder provided above 23. That is, compressed fluid is supplied to the fluid pressure cylinder 47 from the fluid pressure conduit 50, switching is adjusted by the solenoid valves 48 and 49, the piston is slid, the piston rod 35 is moved up and down, and the heating block 31 is moved inside the endless belt 26. For approaching,
Can be separated.

The support arm 52 is equipped with an instrument panel 51 that includes a power switch, a controller for the thermocouple 36, a fluid pressure gauge, other instruments, an air fan for feeding the cooling block 39, etc., so that it can be easily accessed during bonding work. It is better to be able to understand the working conditions.

An example of thermally bonding film ends together using the thermal bonding apparatus according to the present invention will be shown below.

First, the endless belt 6 of the first endless belt mechanism 1
is driven to raise the temperature of the heating block 11, and the temperature of the heating block 31 of the second endless belt mechanism 2 is also raised. Next, the second endless belt mechanism 2 is adhered to the first endless belt mechanism, the endless belts 6 and 26 are brought into contact, and both are rotated in the direction of the arrow in FIG. At this point, the heating block 31 of the second endless belt mechanism is not brought into contact with the inside of the endless belt 26 but is kept apart.

On the other hand, the ends of the plastic films 56 and 57 to be thermally bonded are positioned within the grooves 54 and 55 of the plastic film end guide piece 53, and in the positioned state, they are sandwiched between the endless belts 6 and 26. Include and transfer. During the transfer, the electromagnetic valve 48 of the hydraulic cylinder 47 is opened to send compressed fluid to the upper side of the piston, and when the piston rod 35 is lowered, the heating block 31 comes into contact with the endless belt 26. The heat of heating blocks 11 and 31 is conducted to the film via endless belts 6 and 26, respectively. Then, by the pressing force applied to the heating block 31, they are thermally bonded.

If the part to be thermally bonded is made longer, the upper side of the piston of the fluid pressure cylinder 47 may be filled with compressed fluid, and the heating block 31 may be pressed against the inner surface of the endless belt 26.

If the parts to be thermally bonded are to be formed in dots at regular intervals, the compressed fluid applied to the hydraulic cylinder 47 may be switched and adjusted using the electromagnetic valves 48 and 49 to move the piston rod 35 up and down.

The heat-bonded parts are each cooled by cooling block 1.
It is cooled by the air blown from 9 and 39 and is transferred to the left side in FIG. After the thermal bonding is completed, the second endless belt mechanism is separated from the first endless belt mechanism, and the heating block 31 is also separated from the inner surface of the endless belt 26.

The thermal bonding device according to the present invention can be provided with a mechanism for supporting a fed film on the side that supplies the film, and a film winding mechanism on the side where the bonded film is fed.

In order to thermally bond plastic films using the thermal bonding apparatus according to the present invention, thermal bonding conditions can be selected depending on the type of plastic, the thickness of the film, etc. The conditions for heating are the temperature of the heating blocks 11 and 31, the pressing force applied to the plastic film bonding area (this can be adjusted mainly by the pressure of the compressed fluid applied to the fluid pressure cylinder 47), and the pressure of the plastic film. It can be adjusted by the transfer speed (which can be adjusted by connecting a transmission to the motor 7), etc.

As exemplified above, the thermal bonding device according to the present invention can be used to bond the ends of two plastic films together, as well as the center portion of the film,
It can be used for a wide range of purposes, such as making the film into a bag, making the film into a tube, and providing a part at the end of the film for passing a pipe or tape through. Any plastic film can be used as long as it can be thermally bonded, and it may also be a film with a special film formed on its surface.

The thermal bonding device according to the present invention has the following effects, and its industrial utility value is extremely large.

(1) Since the thermal bonding device according to the present invention has a wide range of selectable bonding work conditions, it is possible to change and select and bond many plastic films so that the strength of the bonded portion is optimized. The scope of use is extremely wide.

(2) In the thermal bonding device according to the present invention, the pressing force applied to the plastic film bonding portion is applied to the second endless belt mechanism by a fluid pressure cylinder or a toggle, and the heating block of the second endless belt mechanism is controlled by the fluid pressure. Since the adhesive can be adjusted by pressing, it is easy to increase the strength of the adhesive part.

(3) In the thermal bonding device according to the present invention, the heating block of the second endless belt mechanism can be easily approached and separated from the film, so that the thermal bonding portion can be made into a continuous line. In addition to being able to
They can also be placed in dots at regular intervals.

(4) In the thermal bonding device according to the present invention, the first endless belt mechanism is driven, and the second endless belt mechanism is driven by pressing against the first one, so that the film sandwiched between the two is driven. Shear stress is added to
The adhesive part between the films becomes smooth, and
The surface of the film at the bonded portion can also be made smooth, and the transparency of the bonded portion can be made not much different from other areas and thus inconspicuous.

[Brief explanation of drawings]

FIG. 1 is a schematic side view of the main parts of an example of a thermal bonding device according to the present invention, FIG. 2 is a schematic cross-sectional view taken along the line --- in FIG. 1, and FIG. 3 is a schematic cross-sectional view taken along the line --- in FIG. be. In the figure, 1 is a first endless belt mechanism, 2 is a second endless belt mechanism, 3 is a table, 4 and 5 are drive rolls of the first endless belt mechanism, 6 is an endless belt, 7 is a motor, 8, 9 is a pulley, 10 is a belt, 11 is a heating block, 12 is a heater,
13 is a heating block support, 14 is a bolt, 15
16 is the first endless belt mechanism support block, 17 is the axis of the roll 4, 18 is the fixing bolt of the heating block support, 19 is the cooling block, 20 is the cooling block support, 21 is the bolt, and 22 is the cooling The air conduits to the blocks are shown respectively. 23 is a second endless belt mechanism support block, 24 and 25 are rolls, 26 is an endless belt, 31 is a heating block, 32 is a heater, 33 is a heating block guide body, 34 is a bolt, 35 is a piston rod, 37
is the shaft of the roll 24, 38 is the fixing bolt of the heating block guide body 33, 39 is the cooling block, 40 is the cooling block support, 41 is the bolt, 42 is the air conduit to the cooling block, 43 and 47 are the fluid pressure cylinders, 44, 45, 48, 49 are solenoid valves, 4
6, 50 is a compressed fluid conduit, 51 is an instrument panel, 52
53 represents a support arm, 53 represents a plastic film end guide piece, 54 and 55 represent grooves, and 56 and 57 represent plastic films, respectively.

Claims (1)

[Scope of Claims] 1. In an apparatus for thermally bonding a plurality of plastic films by stacking them and sandwiching them between a pair of plastic film transfer endless belt mechanisms provided opposite to each other and transferring them, a first endless belt mechanism is provided. The belt mechanism includes two driving rolls on which the endless belt is stretched, rotatably supported, and a driving means for driving the endless belt on the shafts of the two driving rolls, The second endless belt mechanism is rotatably supported by two rolls on which the endless belt is stretched, and is provided with means for integrally approaching and separating the two rolls from the first endless belt mechanism. and a heating block and a cooling block are provided at positions facing each other through each endless belt in a portion surrounded by the endless belt of each endless belt mechanism, and a second endless belt The heating block provided in the mechanism is further provided with means for approaching and separating from the heating block of the first endless belt mechanism from the side of the second endless belt mechanism support block. Plastic film thermal bonding equipment. 2 The two drive rolls of the first endless belt mechanism and the two rolls of the second endless belt roll mechanism are arranged such that the roll axes of each roll are parallel to each other and the endless belts are sandwiched between each other. 2. A plastic film thermal bonding device according to claim 1, wherein said plastic film thermal bonding device is configured to be pivotally supported so as to face each other. 3. A patent claim characterized in that each endless belt mechanism is provided with a heating block and a cooling block at positions surrounded by each endless belt and facing each other across each endless belt. A thermal bonding device for plastic film according to item 1 or 2 of the scope of the invention. 4. Claim 1, characterized in that the means for integrally approaching and separating the second endless belt mechanism from the first endless belt mechanism is constituted by a fluid pressure cylinder. 3. A plastic film thermal bonding device according to item 3. 5 The means for approaching and separating the heating block provided on the second endless belt mechanism side from the heating block of the first endless belt mechanism from the second endless belt mechanism supporting block side is a fluid pressure cylinder. A plastic film thermal bonding device according to any one of claims 1 to 3, characterized in that it is comprised of: