JP3502825B2 - High frequency dielectric heating bonding method of plate material using grid electrode - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION As a method for processing a table top plate, a door, a closet door, etc., a product having a certain thickness by adhering a surface member such as plywood or a decorative plate to the surface of a wooden frame or core plate. There are known methods for processing. In the present invention, as described above, the frame and the core plate (particle board or MDF)
The present invention relates to a method of adhering a surface member to the surface of a core material such as by high frequency dielectric heating.

[0002]

2. Description of the Related Art A method for adhering a surface member to the surface of a core material includes a method of interposing an adhesive between the core material and the surface member and adhering by hot pressing or cold pressing, or by high frequency dielectric heating. A method of heat-bonding a surface member is known. In this method by high frequency dielectric heating, a grid electrode in which positive electrodes and negative electrodes are alternately arranged on the same plane at regular intervals is used, and high frequency dielectric heating between adjacent electrodes is performed between the core material and the surface member. A certain adhesive is heated to bond. As a method for improving the above-mentioned high frequency dielectric heating using a grid electrode, the applicant of the present invention has disclosed in JP-A-11-2
No. 8706 is being developed.

[0003]

In the method of heating the adhesive agent interposed between the core member and the surface member by dielectric heating by the grid electrode, the entire adhesive agent is not always heated uniformly, and the electrode is not always heated uniformly. The heat generation temperature varies depending on the distance from. Therefore, the surface member near the electrode is heated to a higher temperature than the other portions, and the space P is increased as shown in FIG.
It is rare that a streak-like heating mark A is formed along the position of the electrode. In order to solve this drawback, in Japanese Patent Application Laid-Open No. 11-28706 filed earlier, the contact position between the grid electrode and the surface member 2 is intermittently changed so that the bonding is completed by a plurality of high-frequency dielectric heating. did. As a result, it is possible to suppress the formation of heating marks on the surface member. Even if a heating mark is formed, it is a thin heating mark A ′ as shown in FIG. 10 and is inconspicuous.

In the conventional method disclosed in Japanese Patent Laid-Open No. 11-28706, the contact position between the grid electrode and the surface member of the workpiece is intermittently changed and the adhesive is heated to a predetermined temperature by heating a plurality of times. To do. As a result, the temperature rise of the surface member due to one-time heating is lowered, and the heating position can be made inconspicuous by changing the contact position intermittently. However, when intermittently changing the contact position between the grid electrode and the surface member of the work material, it is necessary to temporarily release the pressing of the work material and move the grid electrode or the work material. Therefore, there is a possibility that the work efficiency is deteriorated and the adhesion state is deteriorated due to the release of the pressure during the adhesion. In view of such drawbacks of the prior art, the present invention is capable of performing heat bonding with less generation of heating marks as in the invention described in JP-A No. 11-28706, and improves work efficiency. ,
It is intended to provide a method capable of realizing more reliable adhesion.

[0005]

According to the present invention, a plurality of rod-shaped plus electrodes 4 and minus electrodes are formed on a work material B stacked with an adhesive 3 interposed between a core material 1 and a surface member 2. A grid electrode in which 5 are arranged is brought into contact with the core material 1 and the surface member 2 by heating by heating the adhesive 3 by high frequency dielectric heating between the rod-shaped plus electrode 4 and the minus electrode 5. In this method, the present invention provides an interval P suitable for high frequency dielectric heating.
A plurality of positive electrodes 4 and 4 arranged at intervals smaller than
Between the positive electrode group configuring in, which is suitable for high-frequency dielectric heating
Negative electrode groups composed of a plurality of negative electrodes 5 and 5 arranged at intervals smaller than the interval P are alternately arranged . next to
From the positive electrode group and the negative electrode group that are in contact,
Suitable for heating the adhesive B of the work piece by electric heating
The positive electrode 4 and the negative electrode are in a positional relationship such that the distance P becomes
Select pole 5 and connect this plus electrode 4 to the plus pole 11 of the power supply.
Then, the negative electrode 5 is connected to the negative electrode 12 of the power supply.
Then, by appropriately changing the selection of the plus electrode 4 and the minus electrode 5 connected to the positive electrode 11 of the power source and the negative electrode 12 of the power source, the electrode for high frequency dielectric heating can be changed without releasing the pressing of the workpiece B. However, the surface member near the electrode is prevented from being heated to a high temperature, and the generation of heating marks is suppressed.

[0006] the positive electrode group and the negative electrodes respectively multiple arrangement, either the positive electrodes and the negative electrodes
A combination with an interval suitable for high-frequency dielectric heating selected from
To connect Seno positive electrodes 4 and negative electrodes 5 to the power supply electrodes 6 and 7, 7 and independently
Therefore, multiple power supply electrodes to which the positive electrode is connected, and
A plurality of power supply electrodes to which the inner electrode is connected is provided. That
A plurality of power supply electrodes 6 to which the positive electrodes 4 and 4 are connected.
One of the power source electrodes 7 and 7 to which the negative electrodes 5 and 5 are connected is selected and connected to the negative electrode 12 of the power source. Then, the positive pole 11 of the power source and the negative pole 12 of the power source
The power supply electrode connected to is properly selected and switched. As a result, it is possible to select the combination of the positive electrode 4 and the negative electrode 5 to be energized by one switching operation. Further, by connecting the positive pole of the power source and the negative pole of the power source at a plurality of positions of the power source electrodes 6 and 7 to be energized, the heating balance becomes good. Arrangement of the plus electrode and the minus electrode is arbitrary, for example, adjacent
High frequency dielectric heating is used between the positive and negative electrodes.
Therefore, the interval P is suitable for causing the adhesive of the work material to generate heat.
From the positive and negative electrodes that are alternately arranged at even smaller intervals, select a combination of positive and negative electrodes with an interval suitable for causing the adhesive to generate heat. It may be connected to the pole 12.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION A specific embodiment of a high frequency dielectric heating and bonding method for a plate material using a grid electrode according to the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic front view showing an example of the high-frequency dielectric heating and bonding method according to the present invention, and FIG. 2 is a plan view thereof. According to this high frequency dielectric heating and bonding method, a rod-shaped plus electrode 4 and a minus electrode 5 are provided at regular intervals on the outer surface of a work material B in which an adhesive 3 is applied to the surface of a core material 1 and surface members 2 and 2 are arranged. The adhesive 3 is heated by high-frequency dielectric heating between the plus electrode 4 and the minus electrode 5, and the core material 1 and the surface member 2 are heat-bonded.

In the embodiment shown in FIG. 1, the positive electrode 4 and the negative electrode 5 are arranged on the upper and lower surfaces of the workpiece B, and the surface member 2 is attached to the upper and lower surfaces of the core material. . Rod-shaped electrodes arranged on the lower surface of the workpiece B is a positive electrode 4 and negative electrode 5 at intervals P suitable for high-frequency dielectric heating are alternately arranged, the power supply positive positive electrode 4 via the power supply electrode 6 In addition to being connected to the pole 11, the negative electrode 5 is connected via the power electrode 7 to the negative electrode of the power source, specifically, for example, the ground electrode. As a result, the high-frequency dielectric heating between the adjacent plus electrode 4 and minus electrode 5 causes the adhesive 3 of the work material B to generate heat. The high frequency dielectric heating between the plus electrode 4 and the minus electrode 5 is continued until the heat bonding is completed.

The electrodes arranged on the upper surface of the work material B are two plus electrodes 4, 4 and two minus electrodes 5, 5 arranged at regular intervals. Each electrode has a one-half spacing P suitable for high-frequency dielectric heating. In other words, the two positive electrodes 4 and 4 are a positive electrode group, the two negative electrodes 5 and 5 are a negative electrode group, and the positive electrode group and the negative electrode group are arranged at an interval P suitable for high frequency dielectric heating. . The positive electrodes 4 and 4 selected one by one according to the arrangement from the individual positive electrode groups are connected to one power supply electrode 6. Similarly, minus electrodes 5 and 5 selected one by one according to the arrangement from each minus electrode group are connected to one power supply electrode 7. Therefore, in the case of the embodiment shown in FIG. 1, there are two power supply electrodes 6 (6A, 6B) connected to the plus electrode 4 and two power supply electrodes 7 (7A, 7B) connected to the minus electrode 5. It will be.

One of the two power supply electrodes 6A and 6B is connected to the positive electrode 11 of the power supply, and one of the two power supply electrodes 7A and 7B is connected to the negative electrode 12 of the power supply. (Ground power). That is, when connecting the power electrode 6A connected to the electrode located at the head of the positive electrode group to the positive electrode 11 of the power supply, the power electrode 7A connected to the electrode located at the head of the negative electrode group is connected to the negative electrode 12 of the power supply. Connecting. At this time, the power electrode 6B connected to the next electrode of the positive electrode group and the power electrode 7B connected to the next electrode of the negative electrode group are in a suspended state. When connecting the power supply electrode 6B to the positive pole 11 of the power supply, the power supply electrode 7B is connected to the negative pole 12 of the power supply. Power electrodes 6A, 6B
And the connection of the positive pole 11 of the power supply and the connection of the power supply electrodes 7A and 7B and the negative pole 12 of the power supply are linked so that they can be simultaneously switched.

In high-frequency dielectric heating using a grid electrode, when a high-frequency current is applied between the adjacent positive electrode 4 and negative electrode 5, the layer of the adhesive 3 having a high dielectric loss coefficient is more selectively selected. When heated, the adhesive 3 internally generates heat and the core material 1 and the surface member 2 are heat-bonded. At this time, at the same time that the layer of the adhesive 3 generates heat, a part of the surface member close to the electrodes also generates heat to form the high temperature region 8 of the surface member.
If heating is continued until the bonding is completed in this state, the high temperature region 8 becomes overheated, and the influence of heat is generated, for example, when the surface member has a coating layer formed of vinyl chloride resin or other synthetic resin material. If it is susceptible to heat, the luster and texture may change, and as shown in FIG. 9, heating marks A may be generated on the surface of the work material B at regular intervals P.

FIG. 3 is a partially enlarged view showing the relationship between the electrodes and the workpiece on the upper surface of the workpiece B shown in FIG. As an example, the grid electrode is integrated by inserting the plus electrode 4 and the minus electrode 5 into the groove formed in the electrode board 9 made of a silicon laminated plate, and performing high-frequency dielectric heating with the work piece B pressed by the electrode board 9. To do. In the process shown in FIG. 3 (a), the work piece B is pressed by the electrode board 9 and the positive electrode 4A and the negative electrode
The heating process of the 1st step which applied the high frequency current between 5A is shown. At this time, the heating region 10 shown by the solid line is formed between the plus electrode 4A and the minus electrode 5A arranged at the interval P suitable for high frequency dielectric heating, and the adhesive 3 is heated.

In the heating step shown in FIG. 3 (a), when the bonding of the surface member 2 is completed, specifically, when about half the time until the bonding is completed, the first step shown in FIG. 3 (b) is performed. Switch to a two-step heating process. This second heating step is high-frequency dielectric heating between the second plus electrode 4B of the positive electrode group and the second minus electrode 5B of the minus electrode group, and includes the plus electrode 4B and the minus electrode 5B. A heating region 10 'shown by a solid line is formed therebetween. The heating region 10 by the first heating process and the heating region 10 ′ by the second heating process are common in the layer of the adhesive 3, and are high temperature regions 8 and 8 ′ of the surface member 2.
Are formed at different positions. Therefore, while the adhesive 3 is completely heat-bonded by the two-step heating process, the high temperature region of the surface member 2 is dispersed into 8 and 8 '. Therefore, the surface member 2 is not heated to a high temperature, and the generation of heating marks is suppressed. Even if a heating mark is generated, as shown in Fig. 10, a heating mark with little deterioration is generated at a short interval.
A'is formed and is not as noticeable as the conventional heating mark A.

The above-mentioned switching between the first-step heating step and the second-step heating step can be realized by switching the power supply electrodes to be energized while the electrode board 9 continues to press the workpiece B. . Therefore, unlike the case where the pressure is once released, the phenomenon of lifting of the surface member 2 does not occur, and efficient and reliable high-frequency dielectric heating bonding can be realized. In the embodiment shown in FIGS. 1 to 3, the positive electrode group is composed of two positive electrodes, the negative electrode group is composed of two negative electrodes, and the heating process is composed of two stages. The positive electrode group and the negative electrode group may be respectively configured.

The embodiment shown in FIG. 7 has three positive electrodes.
Positive electrode group by 4A ~ 4C, three negative electrode 5A
The minus electrode group is composed of ~ 5C. When each of the positive electrode group and the negative electrode group is composed of three electrodes, the electrodes are arranged at intervals of one third of the interval P suitable for high frequency dielectric heating, and three electrodes are combined to apply high frequency current. The electrode spacing at that time is set to a spacing P suitable for high frequency dielectric heating. In this embodiment, since there are three combinations of energization and the bonding is performed by the three-step heating process, the generation of the heating mark is suppressed as compared with the case where the heating and bonding is performed by the two-step heating process shown in FIGS. 1 to 3. can do. In addition, it is a modification of the method of applying the high-frequency current, and the high-frequency current is applied once for a short time,
The combination of electrodes to be energized may be changed frequently. That is, after the second stage heating is completed, it is possible to switch to the first stage heating and the second stage heating again.

In the embodiment shown in FIG. 8, the positive electrode 4 (4A
~ 4C) and the minus electrodes 5 (5A to 5C) are alternately arranged at intervals smaller than the intervals suitable for high frequency dielectric heating, and the plus electrodes 4 and the plus electrodes 4 located at appropriate intervals from the arranged many plus electrodes 4 A combination of the negative electrode 5 and the negative electrode 5 is selected and connected to the positive pole 11 and the negative pole 12 of the power source. Then, as shown in (a), (b), and (c) in FIG. 8, by appropriately changing the combination of the electrodes connected to the positive pole 11 and the negative pole 12 of the power source, the solid line, the dotted line, and the two-point By changing the electrodes for high-frequency dielectric heating as shown by the chain lines, it is possible to suppress the generation of heating marks appearing on the surface of the workpiece B.

The high frequency dielectric heating and bonding of the plate material may be performed on one side as shown in FIG. 7 or on both sides as shown in FIGS. The embodiment shown in FIG. 1 is a double-sided process, in which the lower surface is processed by the conventional high-frequency dielectric heating bonding method and the upper surface is processed by the high-frequency dielectric heating bonding method according to the present invention. This method is suitable for processing a plate material which has a front surface and a back surface and which does not require an aesthetic appearance on the back surface. On the other hand, the embodiment shown in FIG. 6 processes both the upper surface and the lower surface by the method according to the present invention, and is suitable for processing both the front surface and the back surface beautifully.

FIGS. 4 and 5 show an example of a concrete device for connecting each electrode to the positive pole 11 of the power source or the negative pole 12 of the power source. This device comprises an electrode board 9, a plus electrode 4, and a minus electrode 5 on the lower surface of an elevating frame 13 which is driven up and down by a cylinder (not shown) having a relatively large force capable of pressing a work material B. A grid electrode consisting of. The tips of the plus electrode 4 and the minus electrode 5 are projected outward of the elevating frame 13, and are connected to the power supply electrodes 6 and 7 for each commonly connected electrode.
That is, the first plus electrode 4A of the plus electrode group is projected to the outermost side and connected to the power supply electrode 6A. The second positive electrode 4B of the positive electrode group is the second power electrode 6B from the outside.
Then, one of the power supply electrodes 6A and 6B is selected and connected to the positive electrode 11 of the power supply. In addition, the first negative electrode 5A of the negative electrode group is connected to the power electrode 7A arranged third from the outside, the second negative electrode 5B of the negative electrode group is connected to the power electrode 7B arranged in the innermost, and the power source is connected. electrode
Select either 7A or 7B and connect it to the negative pole (ground terminal) of the power supply.

FIG. 4 shows a connection switching device between the power supply electrodes 6A and 6B to which the plus electrodes are connected and the plus electrode 11 of the power supply. In this connection switching device, a cylinder 14 fixed to the upper part of an elevating frame 13 is expanded and contracted outward, and an attachment 15 is attached to the tip of a cylinder head. The attachment 15 is provided with a cylinder 16 that expands and contracts in the vertical direction, and the power terminal 17 of the positive pole 11 of the power source is attached to the tip of the cylinder head. With this structure, the power electrode that is turned on and off when the cylinder 16 expands and contracts and is connected by the expansion and contraction of the cylinder 14.
6A and 6B can be selected. That is, by operating the two cylinders 14 and 16, the power supply electrodes 6A and 6B connected to the positive electrode 11 of the power supply, in other words, the positive electrode 4A to be applied,
4B can be switched.

FIG. 5 shows a connection switching device between the power supply electrodes 7A and 7B to which the negative electrodes are connected and the negative electrode 12 of the power supply. In this connection switching device, a cylinder 19 that expands and contracts inward is fixed to the tip of a mount 18 that projects outward from the upper part of the elevating frame 13, and an attachment 20 is attached to the tip of the cylinder head. Attachment 20
Is provided with a cylinder 21 that expands and contracts in the vertical direction, and has a power supply terminal 22 connected to the negative electrode 12 of the power supply, that is, the ground electrode, at the tip thereof. With this configuration, the cylinder 21 expands and contracts to turn ON and OFF,
Power electrode 7A connected by expansion and contraction of cylinder 19
7B selection can be made. That is, the power supply electrodes 7A and 7B connected to the negative electrode 12 of the power supply by operating the two cylinders 19 and 21, in other words, the negative electrode 5 to be applied.
Can be switched between A and 5B.

The connection switching devices shown in FIGS. 4 and 5 may be arranged one by one in the entire grid electrode, but they are arranged at a plurality of positions as a characteristic of high frequency dielectric heating.
By connecting to the positive pole of the same power source and the negative pole of the same power source, respectively, the heating balance can be excellent. Further, as the connection switching device, not only a mechanical switching device as shown in the drawing but also a connection switching device capable of quick and frequent switching by electrical control can be used.

[002]

According to the high frequency dielectric heating and bonding method of the plate material by the grid electrode of the present invention as defined in claim 1 or 4, it is possible to prevent the generation of clear heating marks on the surface of the finished product. Even if a heating mark is generated on the surface of the product under the influence of heating, the heating mark has many unclear streak patterns and becomes inconspicuous. In addition, JP-A-11-28706
No need to release the pressing of the work piece by the grid electrode because the relative positions of the grid electrode and the work piece are not changed during the bonding process as in the method described in No. There is an effect that a high-quality product can be stably provided without causing a defect.

According to the second aspect of the present invention, the electrode to be used for high frequency dielectric heating is switched from among a large number of electrodes.
This can be done efficiently by changing the connection of the positive pole of the power source and the negative pole of the power source to the power source electrode. Also,
According to the invention described in claim 3, the entire heat bonding can be performed relatively uniformly.

[Brief description of drawings]

FIG. 1 is a schematic front view showing an example of a high-frequency dielectric heating and bonding method according to the present invention,

FIG. 2 is a plan view of FIG.

FIG. 3 is a partially enlarged view showing a processing state of heat bonding by electrodes on the upper surface of the work material in FIG. 1;

FIG. 4 is a front view of a connection switching device between a power electrode to which a plurality of positive electrodes are connected and a positive electrode of the power source;

FIG. 5 is a power supply electrode to which a plurality of negative electrodes are connected,
Front view of the connection switching device with the negative pole of the power supply,

FIG. 6 is a schematic front view showing another example of the high-frequency dielectric heating and bonding method according to the present invention,

FIG. 7 is a schematic front view showing still another example of the high-frequency dielectric heating and bonding method according to the present invention,

FIG. 8 is a front view showing the arrangement of electrodes, which is still another example of the high-frequency dielectric heating and bonding method according to the present invention,

FIG. 9 is a perspective view showing a state of a product processed by a conventional method,

FIG. 10 is a perspective view showing a state of a product processed by the method of the present invention.

[Explanation of symbols]

1 ... Core material, 2 ... SurfaceDepartmentMaterial, 3 ... Adhesive, 4,4A ~
4C ... Positive electrode, 5, 5A-5C ... Negative electrode, 6,
6A to 6C ... power supply electrode, 7, 7A to 7C ... power supply electrode, 8，
8 '… High temperature area, 9… Electrode board, 10， Ten ', Ten ”… Addition
Thermal area, 11 ... Positive pole of power supply, 12 ... Negative power supply
Pole, 13 ... Lifting frame, 14, 16, 19, 21 ... Cylinder
ー 、 15,20… Attachment, 17,22… Power terminal,
  18 ... Mounting base, A, A '... Heating mark, B ... Work piece.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-59-16750 (JP, A) JP-A-6-206205 (JP, A) JP-A-10-300348 (JP, A) JP-A-11- 28706 (JP, A) JP 11-42755 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B27M 1/08 B27M 3/00

Claims (4)

(57) [Claims] 1. A grid electrode in which a plurality of rod-shaped electrodes are arranged is brought into contact with a work material in which a surface member is laminated with an adhesive agent interposed in a core material, and the rod-shaped electrodes are bonded by high-frequency dielectric heating. In the method of heat-bonding the core material and the surface member by heating the agent, the grid electrode is smaller than the interval P suitable for high frequency dielectric heating.
Between a positive electrode group composed of a plurality of positive electrodes arranged at intervals and a distance smaller than the interval P suitable for high frequency dielectric heating
Negative electrode groups composed of multiple negative electrodes arranged at intervals are alternately arranged, and high frequency induction is performed from the adjacent positive electrode group and negative electrode group.
Suitable for heating the adhesive of the work material by electric heating
The positive electrode and the negative electrode with a positional relationship of P
Select the positive electrode to the positive pole of the power supply and the negative
Connect the electrode to the power source negative pole of the high-frequency dielectric heating method of bonding the sheet material due to lattice electrode, characterized in that a suitably changeable selection electrode connected to the negative pole of the positive electrode and the power supply of the power source. 2. A high frequency wave in which a plurality of positive electrode groups and a plurality of negative electrode groups are alternately arranged and selected from each positive electrode group and negative electrode group.
Connect the positive electrode and the negative electrode of the combination with an interval suitable for dielectric heating to independent power electrodes .
Allows multiple positive electrodes to be connected to multiple power electrodes
When a plurality of power supply electrodes negative electrodes are connected is provided, by selecting one of the plurality of power supply electrodes has a positive electrode connected with connecting to the positive pole of the power source, a plurality of power supplies negative electrode connected The high frequency of the plate material by the grid electrode according to claim 1, wherein one of the electrodes is selected and connected to the negative pole of the power source, and the selection of the power electrode connected to the positive pole of the power source and the negative pole of the power source can be appropriately changed. Dielectric heat bonding method. 3. The high frequency dielectric heating of the plate material by the grid electrode according to claim 2, wherein the positive electrode of the power source and the negative electrode of the power source are connected to the power source electrode to which the positive electrode and the negative electrode are connected at a plurality of positions, respectively. Bonding method. 4. A grid electrode in which a plurality of rod-shaped electrodes are arranged is brought into contact with a work material in which a surface member is superposed with an adhesive agent interposed on a core material, and the rod-shaped electrodes are bonded by high frequency dielectric heating. In the method of heat-bonding the core material and the surface member by heating the agent, high-frequency dielectric heating is applied between the adjacent positive and negative electrodes.
Suitable spacing to heat the adhesive of the work piece due to
A large number of positive electrodes and negative electrodes are arranged at intervals smaller than P , and positive electrodes and negative electrodes having a positional relationship of intervals P suitable for high-frequency dielectric heating for heating the adhesive are selected from the array. High frequency of a plate material by a grid electrode, characterized in that it is connected to the positive pole of the power source and the negative pole of the power source, and the selection of the positive electrode and the negative electrode connected to the positive pole of the power source and the negative pole of the power source can be changed appropriately. Dielectric heat bonding method.