JPH03182324A - Automatic connecting device for plastic sheet - Google Patents

Abstract

PURPOSE:To permit sure connection with an automatic process even when the material of a plastic sheet makes it hard to bond by a method wherein respective end surfaces of two series of plastic sheets are superposed and the superposed parts are heated quickly by hot air of high temperature to connect them automatically through fusion welding. CONSTITUTION:A diagram shows a condition that the end of the raw fabric roll of one unwinder 1b is jointed to the tip end of a sheet Sa, unwanted on another unwinder 1a from a new raw fabric roll, through lapped jointing immediately before using up the plastic sheet Sb of the raw fabric roll of one unwinder 1b. A pair of unwinders 1a, 1b for unwinding respective sheets Sa, Sb are arranged symmetrically with respect to a center line and respective sheets Sa, Sb are guided to the final pinch rollers 5, 5 through first and second pinch rollers 2a, 4a, 2b, 4b and respective sheer cutters 3a, 3b, which are arranged at intermediate positions between respective pinch rollers 2a, 4a, 2b, 4b, then, the ends of both sheets Sa, Sb, which are superposed to each other, are connected by high-temperature hot air from a hot-air nozzle 6 through fusion welding.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an automatic plastic sheet joining device, particularly,
The present invention relates to an apparatus for automatically joining plastic sheets in a manufacturing process conveyance line.

[Conventional technology]

For example, in the manufacturing process of plastic foam sheets for use in building insulation materials, automobile interior materials, etc., it is necessary to join unfoamed plastic sheets before the foaming process when changing the raw material rollers in the conveyance line. In some cases, when the dimensions of the plastic sheet are, for example, about 0.3 to 4.0 mm in thickness and 200 to 1,000 mm in width, joining has conventionally been carried out using the following methods. In other words, 1) pasting together with tape, 2) overlapping and securing with adhesive, 3) sewing with a sewing machine, 4) heat-sealing, etc.

Needless to say, it is desirable that this type of joining be automated in the conveyor line so as not to interrupt the manufacturing process. In addition, the conveyance process for these sheets is usually 30 minutes.
Since it is operated with a tension of about 50 kg, it is necessary to withstand this tension.

[Problem to be solved by the invention]

However, each of the conventional bonding methods described above has the following inherent problems. In short, 1) The tape method mainly relies on manual labor, and if the joint requires high tension, the tape itself is not strong enough, so it is necessary to apply multiple layers. However, it has been difficult to automate the bonding process.

2) Adhesive method is used when the sheet is made of a material that is difficult to adhere to, such as PE (polyethylene) or PP (polypropylene), and there is no suitable adhesive. Using adhesives has the disadvantage of complicating equipment when automating.

3) The sewing machine method is easy to automate, but when high tension is required, local force is applied to the plastic sheet through the sewing thread, and the sheet itself tends to tear easily.

4) Thermal bonding method tends to increase the distortion of the sheet due to heating and impair the flatness of the sheet, and especially when the sheet contains a foaming agent, this process There was a risk of local foaming, etc.

The present invention was made in view of the problems of the conventional methods as described above, and aims to provide an apparatus for automatically and reliably joining plastic sheets during the conveyance process.

(Means for Solving the Problems) Therefore, in the present invention, a pair of plastic sheet unwinding means are arranged facing each other substantially symmetrically in sequence toward the center, and a first plastic sheet unwinding means is provided. and second
two pairs of pinch roller means each consisting of a pinch roller, each cutter means disposed between the first and second pinch rollers, a hot air nozzle means disposed at the center, and a final stage pinch roller. an automatic plastic sheet joining device comprising means for guiding each plastic sheet unwound from each of the pair of plastic unwinding means, respectively, to the central portion facing each other in the aforementioned order; In order to achieve the above-mentioned object, the respective ends of the two plastic sheets combined are overlapped and guided to the final stage pinch roller means, and this overlapping part is heated with hot air by the hot air nozzle. It is something to do.

[Effect]

With the configuration of the automatic bonding device as described above, even in the case of materials that are difficult to bond, it is possible to quickly heat only the fused surfaces of the sheets using high-temperature hot air to quickly heat only the fused surfaces of the sheets with high-temperature hot air. Fusion can be done in an automated process.

(Example) The present invention will be explained below based on examples.

FIG. 1 shows a schematic configuration diagram of an embodiment of an automatic plastic sheet joining apparatus according to the present invention.

This equipment is used to transport thermoplastic resins, especially plastic films such as PE and PP that are difficult to bond with adhesives, to the raw rolls that are to be fed during the transport process in the foam sheet manufacturing process, which is foamed in the subsequent process. This is a device that overlaps the sheet end of the current roll onto the unwound end of the new roll and fuses it with high-temperature hot air when switching to a new roll after it has been used. be.

(Configuration) In Figure 1, the original fabric rolls are used alternately! For example, in a pair of unwinding machines 1a/1b &:, just before using up the plastic sheet (hereinafter simply referred to as a sheet) Sb of the original roll of one unwinding machine 1b, the end thereof is placed on the unwinding machine la. Sheet Sa unwound by a new raw roll
In this device, a pair of unwinding machines 1a and 1b for unwinding the respective sheets Sa/SbO are disposed centrally symmetrically with each other, and each The sheets S a / S b are sequentially moved toward the center by the first/second pinch rollers 2 a
/ 4 a and 2 b/4 b and each shear cutter 3 a / 3 b disposed in the middle of each of these pinch rollers 2 a / 4 a, 2 b / 4 b, respectively, to the final stage in the central part. The ends of the two sheets Sa/Sb are led to the pinch roller 5, where the ends of the sheets Sa/Sb are fused together by high-temperature hot air from the hot air nozzle 6, and a new sheet S is formed.
It is configured to be supplied to the production line as

Each of the pinch rollers 2a/2b, 4a/4b
.

Each cutter 3 is configured such that one of the rollers can reciprocate in the direction of the arrow shown in the figure to open/close the roller.
A/3B and the hot air nozzle 6 are also configured to be able to operate/retract by reciprocating in the directions of the respective arrows. In addition, in the figure, 7 is a damper for opening and closing hot air, and 8a
, 8b are each sheet guide which is turned around its center point and allows the cut end of the sheet to fall with the punch roller 4a or 4b open.

(motion) Next, the operation in the above configuration will be explained.

The sheet used here has a thickness of, for example, 0.3 to 4.0
PE with a width of about 200 to 1000 Ils.

Or it is a PP material, and the sheet resistance capacity is 20~20 per full width.
The weight shall be approximately 80 kg.

During normal operation of the production line, each pinch roller la/4a,
lb/2b are all open, only the pinch roller 5 is closed, and the sheet Sa or sb from either unwinder 1a/lb is spliced and supplied as S to the production line. Moreover, at this time, each cutter 3a/3b and the #I style nozzle 6 are raised and withdrawn.

Here, as mentioned above, the operation sequence when the sheet sb of the original fabric roll in the unwinding machine 1b is used up and the sheet Sa of the new fabric roll in the unwinding machine 1a is changed will be explained based on FIG. do.

1) First, the sheet Sa from the unwinding machine 1a is inserted immediately after opening the vinyl roll 2a, and then it is closed and left in a standby state.

2) 4! - When the sheet sb of the output machine 1b is finished, a sensor for the outer diameter of the raw roll or other sensor (not shown) detects whether or not a predetermined amount of sheets is present, and when the predetermined minimum amount is reached, This conveyance line is temporarily automatically stopped by the output signal, and the line drive control system is switched for bonding time.

3) Then, under the control of a predetermined program, each pinch roller 2b and 4b closes, and the cutter 3b descends to cut the sheet sb.

4) Next, the sheet Sa is unwound from the unwinding machine 1a, and the r
It is driven and pulled by the pinch roller 2a in the jjjJ1 state, and stops immediately after its tip passes the open pinch roller 4a, and closes the pinch roller 4a.
The cutter 3a is operated to cut the leading end of the sheet Sa.

5) The sheet guide 8a disposed on the sheet SaT side between the cutter 3a and the pinch roller 4a rotates the leading edge of the separated sheet, and the pinch roller 4a is released and the sheet is dropped. let

6) Next, each pinch roller 2a, 4a starts rotating while remaining closed, and the leading end of the sheet Sa is advanced.

7) After a predetermined time T seconds from the start of the rotation, each of the pinch rollers 4b and 5 starts rotating and advances the remaining sheet sb of copper in the unwinding machine 1b. This will be an overlap margin (for example, about 30 to 120 m5).

8) When the leading edge of the sheet Sa reaches the pinch roller 5, the entire movement is stopped.

9) Then, at the same time as the hot air nozzle 6 descends to the sheet guide, the damper 7 is opened and high temperature hot air is blown out from the nozzle 6 to heat the sheet Sa. The width of the nozzle 6 at this time is the maximum value of the sheet guide + 100 mm or more, and the hot air temperature at the nozzle 6 outlet S is approximately 300-400 mm.
00℃, air volume is 5-25Nm'/a+in (350
The distance between the nozzle 6 and the sheet Sa during heating is approximately 5 to 50 mm.

10) After the damper 7 is opened, the sheet Sa is stopped and heated for 2 to 10 seconds (usually 3 to 6 seconds), then the damper 7 is closed, and at the same time as the nozzle 6 is raised, each pinch roller 2a,
4a and 5 are rotated, and the pinch roller 5 presses/fuses the two sheets Sa and Sb. When this stacking passes through the pinch roller 5, the rotation is stopped.

11) All pinch rollers 2a/4a and 2b/4b are opened, the drive control system is switched from one for bonding time to one for line drive control, the production line is started, and the sheet S is operated to be supplied. Both unwinders 1a and 1 perform this operation.
Repeat alternately for b.

It should be noted that all the above operations require about 90 to 180 seconds, and in the above example, the drive control system was switched during this period to stop the operation line. By providing an accumulator system consisting of a group of rolls and configuring the rolls to advance for the above-mentioned required time, it is possible to carry out the automatic splicing operation continuously without stopping the production line.

(Cooling device) In addition, a cooling/heat shielding means is provided to prevent the nozzle 6 itself from overheating during high-speed heating by the high-temperature hot air and to prevent heat from affecting the main bodies of both sheets Sa and Sb other than the joint portions. This is desirable.

FIG. 2 shows a schematic diagram of the main parts of one example.

In the figure, 9 is a cooling conduit for passing a cooling medium such as water, which is disposed outside the base of the nozzle 6 outlet, and 10 is a cooling conduit for passing a cooling medium such as water, which is disposed outside the conduit facing the bodies of both sheets Sa and Sb in the vicinity, respectively. It also serves as a sheet guide to prevent each sheet from coming into contact with high-temperature parts of equipment and causing quality abnormalities. Furthermore, cooling means (not shown) are provided inside both rolls of the pinch roller 5.

Note that 11 is an actuator for moving the nozzle 6 and damper 7 up and down together.

(Effects of the Invention) As explained above, according to the present invention, the respective end surfaces of two series of plastic sheets are overlapped and that portion is rapidly heated with high-temperature hot air and automatically fused and bonded. Even if the plastic sheet is made of a material that is difficult to bond, it is now possible to reliably bond it using an automated process.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of an embodiment of an automatic plastic sheet joining apparatus according to the present invention, and FIG. 2 is a schematic diagram of the essential part configuration of an embodiment of the cooling device. ja, 1b=... Unwinding machine 2a, 4a; 2b, 4b, 5--
--=Pinch rollers 3a, 3b...Cutter 6...Hot air nozzle 7...Damper 8a, 8b=-Sheet guide Sa.

Claims (1)

[Claims] a pair of respective plastic sheet unwinding means each disposed oppositely and substantially symmetrically sequentially toward the center;
two pairs of pinch roller means each consisting of a first and second pinch roller; each cutter means disposed between the first and second pinch rollers; and a hot air nozzle disposed at the center. An automatic plastic sheet joining device comprising a means and a final stage pinch roller means,
Each plastic sheet unrolled from each of the pair of plastic unwinding means is led to the central part facing each other in the aforementioned order, and each end of the plastic sheets that have been combined at the central part are overlapped. An automatic plastic sheet joining apparatus characterized in that the plastic sheets are guided to the final stage pinch roller means and the overlapping portion is heated with hot air by the hot air nozzle.