JPS5856503B2 - film settsugosouchi - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a vinyl acetate film that is used to bond mutually polymerized films, such as by joining the edges of a plurality of vinyl acetate films or both edges of a single film to each other. This invention relates to a method for joining films.

Conventionally, this type of bonding method includes a method in which a polymeric film is sandwiched between a pair of upper and lower heating rollers, and the films are melted and bonded by the heat of the heating rollers.

However, when trying to bond vinyl acetate film using this method, for example, if the film is thin, it will simply soften at a humidity of 78°C, and if the temperature is raised to 76°C, the film will melt and heat up. It had the disadvantage that it stuck to the roller, making it difficult to join them together.

Furthermore, between 73°C and 76°C, there are parts where the bonding is complete and parts where it is incomplete, resulting in variations in the finish.

The same goes for thick ones; they only soften at 76°C, and melt when heated to 84°C;
Between 6° C. and 84° C., variations in finish occurred, making it difficult to achieve good bonding.

Another method is to use, for example, 4
There is a method in which a high frequency wave of 0.46 MHz or 41.14 MHz is applied to heat the film and bond the films.

However, even in the case of such a method, for example, when attempting to bond a vinyl acetate film, the film only becomes soft, making it difficult to bond.

Therefore, the present invention aims to eliminate the above-mentioned drawbacks (it is possible to successfully and continuously bond films made of materials such as vinyl acetate, which are difficult to bond continuously using conventional bonding methods using only high frequency or heat). The present invention aims to provide a film bonding method that can achieve extremely high work efficiency.

Below, drawings showing embodiments of the present invention will be described.

Reference numeral 1 denotes a drive shaft, which is rotatably supported by a bearing provided on a machine body (not shown) and is rotated by a drive groove of a motor or the like.

Next, the lower roller 2 attached to the drive shaft 1 will be explained.

3 is a boss, and 4 is an insulator fixed to the boss 3, and is made of a material such as Teflon that has excellent heat resistance, insulation properties, and high frequency characteristics.

5a and sb are conductive rings fixed to the outer periphery of the insulator 4 in the form of a brim, and are made of a material through which high-frequency and low-frequency currents can easily pass.

Reference numeral 6 denotes a crimp ring fixed to the conductive ring 5a, which is made of a conductive material that allows high frequency current to pass through easily, and has a crimp surface 6a formed by providing a large number of notches on its outer peripheral surface.

Reference numeral 7 denotes an insulating plate made of a highly insulating material such as Bakelite.

Reference numeral 8 denotes a case body that constitutes the outer periphery of the lower roller 2.

Next, 9 is built into the lower roller 2 and has a conductive ring 5a;
A heater connected to 5b is provided to forcefully heat the crimp ring 6, and for example, a heater with a capacity of 24 W is used.

Reference numerals 10a and 10b are power supply brushes placed in contact with the conductive rings 5a and 5b, and are provided to supply low frequency alternating current power (commercial power) to the heater 9.
is also connected to a high frequency power supply circuit so that high frequency current can also be supplied to the crimping surface.

Next, reference numeral 11 denotes a lifting rod that can be raised and lowered with respect to a machine body (not shown), and 12 denotes a frame attached to the lower end of the lifting rod 11, which is made of a material with good thermal conductivity.

Also, this, together with the lifting rod 11, is made of a material through which high frequency current can easily pass.

Reference numeral 13 denotes an upper roller rotatably attached to the frame 12, and has a pressing surface 13a formed with numerous notches on the outer circumferential surface.
is disposed so as to face the pressing surface 6a of the lower roller 2.

The roller 13 is made of a material that has good thermal conductivity and is easy to conduct high frequency current.

A heater 14 is embedded in the frame 12 and is provided to heat the crimp surface 13a via the frame 12. For example, a heater having a capacity of 16 to 24 W is used.

A connection terminal 15 is connected to the heater 14 and is fixed to the frame 12 via an insulating plate 16.

A thermostat 17 is connected to the heater 14 and is provided to keep the temperature of the crimp surface 13a constant.

Note that it is preferable to provide this on the lower roller 2 as well. In the case of the above structure, the heaters 9 and 14 are energized and the pressure bonding surfaces 6a and 13 of the lower and upper rollers 2 and 13 are heated.
A is heated to an appropriate temperature, and the brush 10a and the lifting rod 11 (the body connected thereto) are connected to a high frequency power circuit to apply a high frequency voltage between the crimping surfaces 6a and 13a.

In this state, the bonded portion 19 of the film 18 to be bonded is sandwiched between the rollers 2 and 13, and the lower roller 2 is rotated in the direction of the arrow.

(The upper roller 13 is rotated by the lower roller 2 via the bonded film 18.

) Then, the bonding portions 19 of the film 18 to be bonded are successively melted by the interaction between the heat from the heater 9.14 and the high frequency waves applied to the side pressure bonding surfaces 6a, 13a, and the bonding force of both rollers 2, 13 causes It is glued and sent out.

The appropriate heating temperature of the side pressure bonding surfaces 6a, 13a and the high frequency input power applied thereto are determined depending on various conditions such as the nature of the film to be bonded or its thickness. Values such as a temperature of 77 to 83° C. and a high frequency power of 40 MH and 500 W are used.

In this example, the above-described structure was used as a means for attaching heaters to the upper and lower rollers and a means for connecting the respective crimping surfaces to a high-frequency power circuit.
This may use opposite structures, the same structure as either one, or other known structures.

As described above, in this invention, the film 1 is provided between the pressing surfaces 13a and 6a of the upper and lower rollers 13 and 2, respectively.
Since the film is joined by sandwiching the joining part 19 of No. 8 and rotating the above-mentioned roller, the joining part can be joined continuously and the work efficiency can be extremely high. Of course, in that case, both rollers 13
, 2 are heated to a temperature of 73° C. or higher, and a high frequency voltage is simultaneously applied between the pressure bonding surfaces 13a and 6a, so that the bonded film 18 is a vinyl acetate film. However, the interaction between these heat and high frequency waves allows for good continuous bonding, and it has the advantage that the bonding efficiency is several times higher than that of conventional high frequency welders.

[Brief explanation of drawings]

The drawings show an embodiment of the present application, and FIG. 1 is a side view of the bonding device, FIG. 2 is a front view thereof, and FIG. 3 is a longitudinal sectional view of the lower roller. 2...Lower roller, 13...Upper roller, 5a. 13a...Crimping surface, 9, 14...Heater, 18...Film to be bonded.

Claims (1)

[Claims] 1. An upper roller and a lower roller, each having a crimping surface formed of a conductive material on the outer periphery thereof, are placed in a state facing each other so that the vinyl acetate film to be bonded can be sandwiched between the crimping surfaces of each other. The rollers are arranged so as to be rotatable so as to feed out the film, and the upper roller and the lower roller are provided with heaters capable of heating their respective crimping surfaces, and furthermore, the side crimping surfaces are Heating each of the crimping surfaces of the upper roller and the lower roller to a temperature of 73° C. or higher by means of devices each connected to a high-frequency power supply circuit so as to apply a high-frequency voltage between the crimping surfaces; A method for joining vinyl acetate films, characterized in that the vinyl acetate films to be joined are joined by jointly applying a high frequency voltage between both the front facing surfaces of the heated rollers.