JP2001096624A - Device and method for joining sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for efficiently, uniformly and continuously hot- joining a plurality of synthetic resin sheets laid in a working area and a method for joining using the device. SOLUTION: The joining device 1 of sheets is equipped with a truck 2, which is freely movable along the joining parts 22 of joining means 3 provided on the truck 2. The joining means 3 has a hot air generating means 4 for spraying hot air from the top surfaces of the joining parts 22 of the sheets 21, a roller device 5 for pressing the joining parts 22, which are partly melted by the sprayed hot air, from their top surfaces and a cooling part 7 for quickly cooling and setting the joining parts 22 pressed with the roller device.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for thermally joining seams of a number of synthetic resin sheets laid in a work area to each other and a joining method using the same, and more particularly, to a joining method using the sheets along a joint portion thereof. That can be thermally bonded efficiently and uniformly while moving to

[0002]

2. Description of the Related Art For example, in the periodic inspection work of a nuclear power plant, the floor and wall surfaces of the work area are covered with a sheet (so-called curing) to prevent radiation contaminants from adhering to those surfaces. I have. In that case, a flame-retardant sheet made of a synthetic resin is used as the sheet from the viewpoint of safety. Usually, a required number of sheets of standard dimensions are joined together to cure the floor or wall surface. As a method of joining the edges of adjacent sheets, a special tape such as a flame-retardant tape or a thin iron or aluminum metal tape has conventionally been used. That is, this is a method in which a special tape is adhered along both edges (laminated portions) of the laid sheet.

[0003]

However, the method of joining the edges of the sheets with special tape involves consuming a large amount of expensive special tape, and separating the special tape together with the sheet as radiation-contaminated waste every time construction is completed. There is a problem that is discharged. In addition, it takes considerable skill and labor to attach a special tape so that the radiation-contaminated liquid does not leak from the joined portions of the sheets. As a method for solving such a problem, there has been proposed a method for thermally bonding edges of adjacent sheets. In this method, a portable small hot air heater and a pressing roller are used, and first, the edges (joining portions) of adjacent sheets are heated and partially melted by a hot air heater, and then the sheet is pressed by a pressing roller. Pressing and joining. However, in the method of sequentially joining while holding a tool such as a hot air heater or a pressing roller by hand, it is difficult to perform uniform thermal joining because of poor efficiency. Therefore, it took a long time to construct, and there was a possibility that the radiation contaminated liquid might leak from the joint. Therefore, an object of the present invention is to solve such a problem of the conventional thermal bonding method, and to provide a bonding apparatus and a bonding method using the same, which can efficiently and uniformly bond a sheet joint. It is assumed that.

[0004]

The present invention for solving the above-mentioned problems is an apparatus for thermally bonding synthetic resin sheets 21 to each other, comprising a cart 2 which can freely travel along a joint 22 of the sheets 21. And a joining unit 3 provided on the carriage 2. The joining unit 3 includes a hot air generating unit 4 that blows hot air onto the joining unit 22 of the sheet 21 from an upper surface, and a joining unit 22 that is blown with hot air on the upper surface. Roller device 5 that presses from
And a cooling unit 7 that cools the bonding portion 22 pressed by the roller device 5 from the upper surface. (Claim 1) The roller device may include a support shaft pivotally supported by a cart and a plurality of pressing rollers provided on the support shaft so as to be separated from each other. (Claim 2) The synthetic resin sheet may be a flame retardant sheet. (Claim 3)

Further, a roller device used for thermally bonding synthetic resin sheets to each other is provided with a support shaft and a plurality of pressing rollers provided on the support shaft so as to be separated from each other via a spacer. . Each pressing roller has a heat radiating hole between a shaft penetrating portion provided at a center portion and an outer peripheral portion, and the shaft penetrating portion has an inner diameter larger than an outer diameter of the support shaft. . (Claim 4) Next, in the sheet joining method of the present invention, a step of laying a plurality of flame-retardant sheets in a work area such that their edges overlap with each other; A step of running any one of the joining devices described above along the overlapping portion of the flame-retardant sheet and continuously joining the overlapped portions. (Claim 5)

[0006]

Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a sheet joining apparatus 1 according to the present invention.
FIG. 2 is a side view showing an example, and FIG. In these figures, the joining apparatus 1 includes a truck 2 that can travel on the upper surface thereof along a joining portion of a sheet, and joining means 3 provided on the truck 2. The joining means 3 includes a hot air generator 4 that blows hot air from above on the joining portion of the sheet, a roller device 5 that presses the joining portion of the sheet blown with hot air from above, and a joining of the sheet pressed by the roller device 5. It has a cooling unit 7 for rapidly cooling the unit from the upper surface.

The carriage 2 has a base 2a, a pair of wheel devices 9 such as casters provided on the front side in the traveling direction of the base 2a and capable of changing directions, and an operation handle 8 for operating the base 2a. Further, the wheel device 9 is provided with a spring 9a so that the wheel can move up and down with respect to the base 2a. The operation handle 8 is rotatably connected to a receiving stand 10 provided on the base 2a.
Is made telescopic so that the length can be adjusted. As described above, since the direction of the wheel device 9 can be changed,
The joining device 1 can be caused to travel along the smoothly bent joint. In addition, the support mechanism formed into a tricycle by the rear roller device 5 and a pair of front wheel devices 9 and the wheel device 9 can be moved up and down by a spring 9a, so that the pressing roller 6 is moved when the joining device 1 is moved. The base 2a can always be in a horizontal state with respect to the floor surface with the base axis as a reference axis. Furthermore, since the operation handle 8 is made rotatable and extendable and retractable with respect to the base 2a, it is possible to perform the joining operation of the seat in an optimal posture.

As the hot air generator 4, for example, a commercially available hot air heater as shown in the figure can be used. The hot air generator 4 includes a main body 4a and a nozzle 4b extending therefrom. An electric heater and a blower fan are built in the main body 4a, and the generated hot air is blown out from an opening at the tip of the nozzle 4b. . The main body 4a is attached to the pedestal 10 so that the vertical position can be adjusted.
The height of the balloon can be adjusted. Such a height adjustment is performed by, for example, providing a plurality of long holes in the up-down direction in the receiving table 10 and adjusting the position of a bolt for fixing the main body 4a using the long holes. Further, the amount of heat generated by the electric heater can be adjusted. When a commercially available hot air heater is used, the nozzle 4b is bent so that its opening is perpendicular to the sheet surface.

The melting temperature differs depending on the material of the sheet used. Therefore, the heating temperature of the sheet is roughly adjusted by adjusting the heat generation amount of the electric heater as described above.
By fine adjustment by adjusting the blowing height of b,
The optimum heating temperature for the sheet can be easily set. The nozzle 4b extends below the base 2a using an opening provided in the base 2a. The outlet of the nozzle 4b has an elongated elliptical slit shape suitable for the joining width of the sheets. By setting the outlet to such a shape, diffusion of heat can be prevented and hot air can be efficiently blown to the joints of the sheets.

The roller device 5 is provided behind the base 2a, that is, behind the nozzle 4b so that the hot air blown out from the nozzle 4b does not directly hit. The cart 2 is driven by the pressing roller 6 of the roller device 5 and the pair of wheel devices 9.
Is supported on the sheet. 3 and 4 show a specific example of the roller device 5. FIG. FIG. 3 is a front view, and FIG. 4 is a plan sectional view. In these figures, the roller device 5 is mounted on the base 2.
a and a spacer 1
It has a plurality (four in this example) of pressing rollers 6 provided apart from each other via the two. Each pressing roller 6 has a shaft penetrating portion 18 provided at the center, and a plurality of penetrating heat radiation holes 13 are provided between the shaft penetrating portion 18 and the outer peripheral portion. The shaft penetrating portion 18 has an inner diameter larger than the outer diameter of the support shaft 11, so that each pressing roller 6 can move vertically with respect to the support shaft 11 independently. How large the inner diameter of the shaft penetrating portion 18 is larger than the outer diameter of the support shaft 11 is determined from a value sufficient to absorb a height of irregularities generated at a joint portion of the sheet described later, but usually about 5 mm. I just need. The support shaft 11 is rotatably supported by the base 2a via a pair of bearings 14.

FIGS. 5 and 6 are side views showing different outer peripheral surfaces of the pressing roller 6. FIG. FIG. 5 shows a pressing roller 6 having a cross ridge formed on the outer peripheral surface, and FIG. 6 shows a pressing roller 6 having a straight ridge formed parallel to the outer peripheral surface. By forming such a large number of protrusions on the outer peripheral surface, it is possible to form a similar pattern on the pressed sheet, thereby more effectively preventing liquid leakage from the joint as described later. Can be. As shown in FIG. 1, the pressing roller 6 in the roller device 5 is a rotary driving unit 15 such as a motor.
Can also be driven. In that case, the rotation drive unit 1
5 is transmitted to the pressing roller 6, the rotation driving unit 1
The output shaft 5 and the support shaft 11 of the pressing roller 6 are connected by a pair of pulleys 16 and a belt 17. The belt 17 is wound between each pulley 16 through an opening provided in the base 2a. When the rotation drive unit 15 is provided, it is preferable that the operation switch be provided on the operation handle 8 so that the start-stop operation can be performed there. In this way, the start and stop operations of the rotation drive unit 15 allow the carriage 2 to move freely and stop.

As shown in FIGS. 1 and 2, the cooling unit 7 is provided above the base 2a behind the pressing roller 6 in the base 2a. As the cooling unit 7, for example, a commercially available general-purpose small-sized blower fan can be used, and the cooling air is sent to the joint of the sheets through an opening provided in the base 2a. The joined portion of the sheet pressed in a partially melted state is rapidly cooled by the cooling unit 7, and the pressed state is fixed. In this example, the cooling unit 7 has both a cooling function of the sheet joining portion and a cooling function of the pressing roller 6.
When the pressure roller 6 comes into contact with the sheet in a partially melted state, the temperature rises, and the pressure roller 6 easily sticks to the sheet. Therefore, the pressing roller 6 is efficiently cooled by the cooling action of the cooling unit 7 and the heat dissipation action of the plurality of heat dissipation holes 13 to maintain the temperature at a low temperature. The reason why the cooling unit 7 is provided behind the pressing roller 6, that is, on the opposite side of the nozzle 4 b with the pressing roller 6 as the center, is to prevent the cooling air from lowering the joining temperature of the sheet due to the hot air blown from the nozzle 4 b. . It is preferable that the operation switch of the blower fan is also provided on the operation handle 8.

Next, the operation of the sheet joining apparatus will be described with reference to FIGS.
This will be described with reference to FIG. 7 and 8 are a side view and a plan view, respectively, showing a state in which the joints of the sheets are thermally joined using the joining apparatus 1 of FIG. 20 in the figure is a floor surface, 2
1 is a sheet laid thereon. In the periodic inspection work in the nuclear power plant, the sheet 21 is usually a flame-retardant sheet. As the flame retardant sheet, a sheet obtained by mixing a non-halogen flame retardant such as a halogen flame retardant such as bromine into a synthetic resin such as vinyl chloride, polyethylene, polystyrene, or polyamide is generally used. (For example, commercially available products include a transparent vinyl chloride flame-retardant sheet mixed with a halogen-free flame retardant manufactured by Sekisui Chemical Co., Ltd., trade name "Sanvic", etc.) As shown in FIG. The edges of the sheet 21 are overlapped with each other to form a joint 22. The width S of the joining portion 22 is not particularly limited, but is preferably in a range of about 5 to 6 cm.

Prior to the joining operation, the joining device 1 is
It is arranged at the joining start portion on one joining portion 22. that time,
The front-back direction of the base 2 a is made to coincide with the longitudinal direction of the joint 22. Then, the hot air generating unit 4 and the cooling unit 7 are activated, and the nozzle 4
By operating the operation handle 8 while heating the joint 22 of the sheet 21 by blowing hot air from b, the carriage 2 is moved at a constant speed. As a result, the joining portion 22 is partially and automatically melted by heating, adhered by pressing force, and fixed by cooling sequentially and automatically. The heating temperature of the joint portion 22 is set so that it is partially melted. Since the melting temperature varies depending on the material of the sheet to be used, conditions for obtaining an optimum temperature suitable for the material are selected. That is, the joint 2
The temperature 2 changes depending on the hot air temperature, the distance between the tip of the nozzle 4b and the joining portion 22, the moving speed (ie, the heating time), and the like. For example, when a flame-retardant sheet having the trade name “Sanvic” is used, the temperature is set to 85 to 95 ° C., preferably about 89 ° C. The outlet of the nozzle 4b is connected to the joint 2 as much as possible.
It is desirable to adjust the angle or the like so as to be perpendicular to the surface of No. 2.

The joining portion 22 which has been partially melted is welded by the pressing of the pressing roller 6. The pressing force of the pressing roller 6 is roughly determined by the load of the joining device 1, but a larger pressing force can be applied to the joining portion 22 by applying a downward force to the operation handle 8. The pressed joint is then rapidly cooled by the cooling unit 7 to fix the state. The temperature of the outer peripheral surface of the pressing roller 6 is usually 40
~ 60 ° C, preferably about 45 ° C. When the joining portions 22 are thermally joined in this manner, a plurality (four) of linear joining bands 23 formed by the pressing rollers 6 are formed as shown in FIG.

FIG. 9 is an enlarged view of the joint portion 22 in which the linear joint band 23 is formed. A joint 22 is formed by the upper sheet 21a and the lower sheet 21b whose edges are overlapped, and four joint bands 2 are formed along the longitudinal direction of the joint 22.
3 are formed in parallel at predetermined intervals. By using the cured sheet 21, for example, the radiation-contaminated liquid that diffuses to the upper surface of the joint 22 tends to leak from the joint of the joint 22 to the lower part. This is reliably prevented by the bonding band 23. At this time, by using the pressing roller 6 having a cross ridge or a straight ridge formed on the outer peripheral surface, an uneven pattern corresponding to the shape of the ridge is formed on the joint portion 22 as illustrated. Then, the degree of adhesion of the joining portion becomes larger than that of the other parts due to the protruding ridge portions (parts strongly pressed) of the concavo-convex pattern, so that the leakage preventing action can be further improved by the part having a high degree of adhesion. FIG.
3 is a partially enlarged view for explaining a liquid intrusion direction 3 and a liquid intrusion direction, wherein the left side of the figure is a joint band 23 formed by cross ridges, and the right side is a joint band 23 formed by straight ridges.

When the joining portion 22 is pressed by the pressing roller 6 as described above, it is possible to provide only one pressing roller 6 and make the width thereof equal to the width of the joining portion 22. However, when the joining portion 22 is continuously pressed and advanced by using the single pressing roller 6, wrinkling in the moving direction of the joining portion 22 is likely to occur. On the other hand, for example, the floor surface of a periodic inspection work area in a nuclear power plant is coated with a resin in order to prevent the leakage liquid from penetrating if the radiation contaminated liquid leaks to the floor. However, if the resin-coated surface is damaged or dust is attached, it is troublesome to remove dust and the like adhering thereto. When the sheet 21 is laid on the scratched portion or the portion where the dust 24 adheres, an uneven portion is generated in the joint portion 22, and it is difficult to perform uniform thermal joining. However, as in the present embodiment, the pressing roller 6 of the roller device 5 is divided into a plurality of parts, and the supporting roller 11 is supported on the supporting shaft 11 in a state where the pressing rollers 6 are separated from each other. By using a large inner diameter, any of the above problems can be solved.

FIG. 11 shows a joining portion 2 between the roller device 5 and the sheet.
FIG. 4 is an explanatory diagram showing a relationship 2; In FIG. 11, floor 2
If the dust 24 adheres to the bonding portion 22 of the sheet 21,
An uneven portion 22a is generated in the area. However, the pressing roller 6 passing through the uneven portion 22a utilizes the gap between the inner periphery of the shaft penetrating portion 18 and the outer periphery of the support shaft 11, and as shown in FIG.
As a result, it escapes upward (in the direction of the arrow) so as to get over "a", so that the uniformity of thermal bonding as a whole is hardly impaired.
In addition, since the swelling of the sheet 21 generated by the continuous pressing progress is divided into small portions by the plurality of pressing rollers 6,
Wrinkling can also be effectively prevented. The sheet 21 used for curing the floor or wall as described above is collected at a predetermined facility after use.

[0019]

As described above, according to the sheet joining apparatus and the joining method of the present invention, there is provided a bogie that can travel along the joined portion of the sheet and the joining means provided thereon, and the joining means is provided with the sheet. A hot air generator that blows hot air onto the joint, a roller device that presses the joint that has been blown with hot air, and a cooling unit that cools the joint pressed by the roller device. As described above, the joining portion of the sheets can be efficiently and uniformly and continuously joined without using a special tape.
The roller device in the sheet joining apparatus may include a support shaft pivotally supported by the carriage and a plurality of pressing rollers provided on the support shaft so as to be separated from each other. With such a configuration, it is possible to substantially prevent the occurrence of wrinkles when continuously pressing the bonding portion of the sheet.

Further, the synthetic resin sheet may be a flame-retardant sheet which is not damaged even if it comes in contact with a high-temperature radiation contaminant or liquid. Furthermore, the roller device included in the sheet joining device of the present invention includes a support shaft,
The support shaft is provided with a plurality of pressing rollers provided apart from each other via a spacer, and each pressing roller has a heat radiating hole between a shaft penetrating portion provided at a central portion and an outer peripheral portion. The part is characterized by having an inner diameter larger than the outer diameter of the support shaft, and by using this, the above-described sheet joining apparatus can be configured.

[Brief description of the drawings]

FIG. 1 is a side view showing an example of a sheet joining apparatus according to the present invention.

FIG. 2 is a plan view of FIG. 1;

FIG. 3 is a specific front view of the roller device 5 in FIG.

FIG. 4 is a plan sectional view of FIG. 3;

FIG. 5 is a side view showing an example of the outer peripheral surface of the pressing roller 6 in FIG.

FIG. 6 is a side view showing another example of the outer peripheral surface of the pressing roller 6 in FIG.

FIG. 7 is a side view showing a state in which the joints of the sheets are thermally joined using the apparatus of FIG. 1;

FIG. 8 is a plan view of FIG. 7;

FIG. 9 is an enlarged view of a joint portion 22 in which a linear joint band 23 is formed.

FIG. 10 is a partially enlarged view for explaining a joining band 23 and a direction in which a liquid enters the joining band 23.

11 is an explanatory diagram showing a relationship between a roller device 5 and a sheet joining portion 22 in FIG. 7;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Joining apparatus 2 Cart 2a Base 3 Joining means 4 Hot air generating part 4a Main body 4b Nozzle 5 Roller device 6 Press roller 7 Cooling part 8 Operating handle 8a Handle shaft 9 Wheel device 9a Spring 10 Receiving stand 11 Support shaft 12 Spacer 13 Heat radiation hole DESCRIPTION OF SYMBOLS 14 Bearing 15 Rotation drive part 16 Pulley 17 Belt 18 Shaft penetration part 20 Floor surface 21 Sheet 21a Upper sheet 21b Lower sheet 22 Joining part 22a Uneven part 23 Joining band 24 Dust

Continued on the front page F term (reference) 4F211 AD05 AD08 AG01 AG03 SA07 SD01 SD16 SH06 SJ15 SP01 SP25 TA13 TC04 TH06 TJ15 TN24 TQ03

Claims (5)

[Claims] 1. A device for thermally bonding sheets 21 made of synthetic resin to each other, comprising: a truck 2 capable of freely traveling along a joining portion 22 of the sheet 21; and a joining means 3 provided on the truck 2. The joining means 3 comprises: a hot air generator 4 for blowing hot air to the joining portion 22 of the sheet 21 from above; a roller device 5 for pressing the joining portion 22 to which the hot air has been blown from the upper surface; A sheet joining apparatus comprising a cooling unit 7 for cooling a pressed joint 22 from above. 2. The sheet joining apparatus according to claim 1, wherein the roller device 5 includes a support shaft 11 supported by the carriage 2 and a plurality of pressing rollers 6 provided on the support shaft 11 so as to be separated from each other. . 3. The sheet joining apparatus according to claim 1, wherein the synthetic resin sheet 21 is a flame retardant sheet. 4. A roller device 5 for thermally bonding synthetic resin sheets 21 to each other, comprising: a support shaft 11; and a plurality of pressing rollers provided on the support shaft 11 so as to be separated from each other via a spacer 12. 6, each pressing roller 6 has a heat radiating hole 13 between a shaft penetrating portion 18 provided at a central portion and an outer peripheral portion,
The sheet joining apparatus according to claim 1, wherein the shaft penetrating portion (18) has an inner diameter larger than an outer diameter of the support shaft (11). 5. A step of laying a plurality of flame-retardant sheets in a work area such that their edges overlap with each other, and the joining apparatus according to claim 1, further comprising: A step of running along the overlapping portion of the flammable sheets and continuously joining the overlapped portions thereof.