JP2002370282A - Resin sheet fusion-bonding method and fusion bonding apparatus therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin sheet fusion-bonding method capable of certainly performing fusion bonding even if moisture adheres to a fusion-bonded part when resin sheets are mutually fusion-bonded. SOLUTION: The mouth part 1a of a bag-like container 1 moved along a predetermined work route is pressed from both sides by press metal fittings 19 and heated by the electric heaters 20 provided to the press metal fittings 19 to be sealed. In this case, vibration is applied to the press metal fittings 19 by an ultrasonic vibration generator 18 to repel the moisture bonded to the inner surface of the mouth part 1a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for welding a resin sheet.

[0002]

2. Description of the Related Art Conventionally, a resin sheet filled with drinking water,
For example, when sealing the mouth of a bag formed of a polyethylene sheet, by heating the mouth of the bag filled with drinking water from both sides and pressing with a pressing member,
The mouth was welded and sealed.

At the time of sealing, moisture (water droplets) adhering to the inner surface of the mouth at the time of filling of drinking water is pressed by pressing the mouth from both sides with a pressing member.
The water adhering to the inner surface of the mouth was pushed out.

[0004]

As described above, according to the system in which the mouth of the bag is pressed from both sides by the pressing member and heated by the heating means provided at the tip thereof, the moisture adhering to the inner surface of the mouth is prevented. May be heated in a state where
Therefore, when the trapped moisture evaporates, the pressure increases, the bag itself expands, and the mouth cannot be reliably sealed.

Accordingly, an object of the present invention is to provide a method and an apparatus for welding a resin sheet that can reliably perform welding even when moisture is attached to a welded portion when welding resin sheets. And

[0006]

In order to solve the above-mentioned problems, a method for welding resin sheets according to the present invention comprises pressing resin sheets from both sides with a pressing member and heating the resin sheets to weld the resin sheets. A method of applying vibration to the resin sheet when pressing the resin sheet.

In another method of welding resin sheets of the present invention, the resin sheets are pressed from both sides by a pressing member, and the resin sheets are heated by heating means provided on the pressing member. This is a method of welding, and is a method of applying ultrasonic vibration to the pressing member to vibrate the resin sheet when pressing the resin sheet.

Further, the resin sheet welding apparatus of the present invention is provided with a pair of pressing members provided on both sides of the resin sheet so as to be able to approach and separate from each other and provided with a heating means at the front end, respectively. An apparatus for welding, comprising ultrasonic vibration generating means for applying ultrasonic vibration to at least one end of the pair of pressing members.

According to each of the above-described welding methods and the configuration of the welding apparatus, when the resin sheets are heated and welded while being pressed from both sides, vibrations, for example, ultrasonic vibrations are applied to the resin sheets. Moisture adhering to the inner surface of the mouth can be removed by vibration.Therefore, compared to the case where the adhering moisture is heated and evaporated, the resin sheet may expand due to volume expansion during evaporation. The occurrence of troubles such as a failure in normal welding can be prevented.

Further, since the removal of water is performed by vibrating the resin sheet, there is no need to heat as compared with the case of evaporating, so that there is no adverse effect on the resin sheet.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A resin sheet welding apparatus and method according to an embodiment of the present invention will be described below with reference to FIGS.

In the present embodiment, the resin sheet (including the resin film) is a bag-like container formed of, for example, a polyethylene sheet filled with a liquid such as a medicine, and the object to be welded is the bag-like container. The description will be made as the mouth of the container.

First, a bag-like container and a process (flow) for filling the bag-like container with a liquid such as a medicine will be briefly described. As shown in FIG. 1, a bag-shaped container (hereinafter, referred to as a bag) 1 is provided with an inlet (a mouth, also referred to as an opening) 1a for a liquid such as a medicine at an upper portion thereof.

The bag 1 is held by a carrier (not shown) that is moved along a predetermined work path via a gripping tool 2 while moving along the work path (also referred to as a movement path). , Bag washing, liquid filling, and welding or sealing of the inlet 1a. In addition, 1
b denotes a liquid outlet provided at the lower part of the bag 1.

Next, the welding apparatus will be described with reference to FIG. The welding device 11 is disposed at the working position of the sealing step of the injection port 1 a, is disposed on both sides of the bag 1 held by the carrier via the gripping tool 2, and is positioned with respect to the injection port 1 a of the bag 1. A pair of holding members 12 (12A, 12B) provided to be able to approach and separate from each other, a holding position (a) for pressing these holding members 12 to press the inlet 2 and a separating position (b) away from the inlet 2 13 (13A, 13B) an air cylinder (an example of a driving device) that reciprocates between
It is composed of

Each of the pressing members 12 is connected to a guide portion (also referred to as a linear guide) 15 disposed on a support base 14 in a direction orthogonal to the moving path of the bag 1 and the air cylinder 13 and the guide member. A moving body 17 having a sliding portion 16 slidably guided by the portion 15 and capable of moving toward and away from the bag 1 and an ultrasonic vibration generator (ultrasonic vibration generating means) Presser fitting (presser) 19 of the injection port 1a protruding toward the bag 1 through the intermediary 18
And an electric heater (an example of a heating unit, also referred to as a heat bar) 20 disposed in the presser fitting 19.

As shown in FIG. 3, the press fitting 19 has an elongated surface so that the injection port 1a of the bag 1 can be pressed from a side at a predetermined height (predetermined width). An abutment 19a is formed, and an electric heater 20 is provided at a rear portion thereof so that the abutment 19a can be heated.
Is embedded.

The ultrasonic vibration generator 18 has a vibrator that generates vibration based on an ultrasonic signal, and the ultrasonic vibration from the vibrator is transmitted to the holding member 19.

Next, the mouth 1 of the bag 1 is
The step of sealing a will be described. In a career,
When the bag 1 is transferred to the sealing process and the mouth 1a is stopped between the holding members 12A and 12B, the holding metal fittings 19 on both sides are moved by the air cylinders 13 on the left and right sides.
a, and the ultrasonic vibration generator 18 applies ultrasonic vibration to the holding member 19.
The electric heater 20 embedded in the holding member 19 is always energized.

When the presser fitting 19 further advances and comes into contact with the mouth 1a to be in a lightly pressed state (the mouth is still open), ultrasonic vibration is applied to (transmitted to) the mouth 1a. ), The moisture adhering to the inner surface of the mouth 1a is repelled by the vibration, that is, atomized.

When the water is removed by the atomization, the ultrasonic vibration generator 18 is stopped, the pressing by the presser fitting 19 is continued, and the heating of the mouth 1a by the electric heater 20 is performed for a predetermined time. The welding or sealing of the portion 1a is performed (the electric heater can be energized simultaneously with the stop of the ultrasonic vibration generator).

When the sealing is completed, the pressing member 12 is moved backward, and then moved to the next cooling step to be cooled by the cooling member (natural cooling may be performed). As described above, when the mouth 1a of the bag 1 is pressed and heated by the holding metal 19 and sealed, the ultrasonic vibration is transmitted to the holding metal 19 by the ultrasonic vibration generator 18 so that the mouth 1a is transmitted to the mouth 1a. Since high frequency vibration (ultrasonic vibration) is applied, moisture (water droplets) adhering to the inner surface of the mouth 1a can be repelled into the air by vibration, and therefore, as in the conventional case, It is possible to prevent the occurrence of a seal failure due to volume expansion due to evaporation of moisture remaining on the inner surface. That is, when the mouth 1a is heated, since moisture is removed, a phenomenon such as volume expansion does not occur, so that the bag itself does not stretch and sealing can be performed normally.

In the above embodiment, the ultrasonic vibration generators are provided on the pressing members on both sides. However, for example, the ultrasonic vibration generators may be provided only on the pressing members on one side. Also,
In the above-described embodiment, the holding member is moved toward and away from the bag-shaped container by the air cylinder.
For example, it is also possible to use a rack and pinion mechanism to approach and separate with an electric motor.

In the above-described embodiment, the case where the mouth of the bag filled with liquid such as medicine is sealed is described. Of course, it is formed of synthetic resin sheet of drinking water other than medicine, food, etc. The present invention is also applicable to a case where the mouth of a bag is sealed.

Further, in the above embodiment, the case where the mouth of the bag-shaped container is sealed has been described. However, the present invention is also applicable to the case where the resin sheets are welded by pressing and heating instead of the bag-shaped container. Can be. Therefore, when the pressing and heating for joining the resin sheets is expressed by the phrase “welding”, when pressing and heating the mouth of the bag-shaped container, it is more preferable to express the phrase by “sealing”. In this case, it can also be referred to as a sealing method and a sealing device.

[0026]

As described above, according to the resin sheet welding method and the structure of the welding apparatus of the present invention, when the resin sheets are heated and welded while being pressed from both sides, vibrations such as ultrasonic waves are applied to the resin sheets. Since the vibration is applied, moisture (water droplets) adhering to the surface of the welded portion can be removed by the vibration. It is possible to prevent problems such as a failure in normal welding due to expansion of the resin sheet.

Further, since the water is removed by vibrating the resin sheet, heating is not required as compared with the case of heating and evaporating, so that the resin sheet is not adversely affected.

[Brief description of the drawings]

FIG. 1 is a schematic front view of a bag-shaped container according to an embodiment of the present invention.

FIG. 2 is a side view showing a schematic configuration of a welding apparatus according to the embodiment.

FIG. 3 is a perspective view of a holding member in the welding device.

[Description of Signs] 1 Bag-shaped container 1a Inlet 11 Welding device 12 Pressing member 13 Air cylinder 17 Moving body 18 Ultrasonic oscillator 19 Pressing bracket 20 Electric heater

Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat II (reference) B65B 51/10 101 B65B 51/10 101 // B29L 22:00 B29L 22:00 F term (reference) 3E075 AA28 BA42 BB02 CA01 DD13 DD34 DD42 DD43 DE25 GA04 3E094 AA12 BA02 CA03 CA06 CA16 DA06 FA22 HA08 4F211 AA04 AD05 AD08 AG01 AG03 AH54 AH63 TA01 TC13 TC14 TC16 TC17 TD11 TH06 TH11 TJ22 TJ30 TN02 TQ05

Claims (3)

[Claims] 1. A method in which resin sheets are welded to each other by pressing and heating the resin sheets from both sides by a pressing member, wherein vibration is applied to the resin sheets when the resin sheets are pressed. A method for welding a resin sheet, comprising: 2. A method in which resin sheets are pressed from both sides by a pressing member, and the resin sheets are welded to each other by heating by heating means provided on the pressing member. At this time, a method of welding a resin sheet, characterized by applying ultrasonic vibration to the pressing member to vibrate the resin sheet. 3. An apparatus for welding said resin sheets to each other by a pair of pressing members provided on both sides of said resin sheet so as to be able to freely approach and separate from each other and provided with a heating means at a front end thereof, respectively. An apparatus for welding a resin sheet, comprising: an ultrasonic vibration generating means for applying ultrasonic vibration to at least one end of the holding member.