JPH0671852A - Method and device for subjecting curved surface to heat transfer by vacuum press - Google Patents

Abstract

PURPOSE:To contrive heat transfer, necessitating uniform high temperature, on a work through vacuum press method by a method wherein a film is bonded to the work and, thereafter, a lid body is separated from the work and the work is contacted with or approached to an external heating body obtained by heating an elastic covering body to a predetermined temperature from the finishing of the work to the starting of next work. CONSTITUTION:An elastic covering body 21 is contacted with a transfer foil 10 and is deformed along the curvature of a work 9 or the three-dimensional configuration of the same while transferring the heat thereof while the transfer foil 10 is pushed against the work 9. When a necessary time for effecting heat transfer on a work having a predetermined configuration is elapsed, one process is finished, a vacuum pump 3 is stopped, a lid body 17 is elevated and an evacuating table 5 is extracted toward an operater again, the external heating body 11 is moved to the lower part of the lid body 17 to contact the covering body 21 with the surface of the heating body 11 whereby the covering body 21 is heated to a predetermined temperature by the external heating body 11 and an internal heating body 22 to recover heat deprived of the work 9 and the transfer foil 10. The work 9 is put on a receiving jig 8 on the evacuating table 5 again and the jig 8 is covered by the transfer foil 10, then, the evacuating table 5 is pushed back in the same manner and the heat transfer work is applied in the same manner.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a curved surface vacuum press thermal transfer method and apparatus thereof, and particularly to a furniture or a building material having a curved surface shape without using an adhesive and with a transfer foil in a short time. The present invention relates to a thermal transfer method and an apparatus therefor.

[0002]

2. Description of the Related Art In general, woodworking products such as furniture and building materials, when a synthetic material obtained by compressing wood chips into a plate shape is used,
Laminating is performed by adhering a film such as a vinyl chloride sheet or the like with wood grain printed on the surface of the cloth with an adhesive.
Therefore, these wood products often have a curved shape, and therefore, a technique for uniformly adhering a film to the curved surface is to press a rubber roller or press a vacuum press. Has been done.

The method of pressing a film against the surface of a work such as a woodworking product having a curved surface with a rubber roller involves considerable difficulty when the curved surface shape is complicated, but the method of pressing with a vacuum press is rather complicated. However, there is an advantage that it can be processed. However, in any case, the conventional laminating process is to apply an adhesive to the film and / or the work to adhere them. Moreover, in this bonding method, heat was used to enhance the effect of the adhesive.

Therefore, the conventional laminating machine is
It has a spray means for applying an adhesive to the film and a heating means for heating the adhesive applied to the film. In the case of, for example, a vacuum pressing method, the heating means is provided with a heater in a lid body in which an elastic cover made of silicon rubber is stretched over the opening, and the lid body is heated to radiant heat to bring the elastic cover to a predetermined temperature. After heating, the lid is lowered toward the decompressor on which the work and the film are placed, the elastic cover and the film are vacuum-sucked along the curved shape of the work, and the inside of the lid is pressed to bring them into contact with each other. By doing so, the film was heated to cure the adhesive.

By the way, recently, when a base film coated with a transfer foil on which wood grain or the like is applied is thermocompression-bonded to a woodwork product,
A so-called thermal transfer method is provided in which the pressure-sensitive and heat-sensitive adhesive applied to the transfer foil is melted to adhere the transfer foil to the work, and the base film itself is peeled off.

According to this heat transfer method, the heat required for the heat transfer is relatively high compared to the case of the above laminating process. Therefore, a method of pressing the film against the work surface with a rubber roller is adopted, and most of the vacuum pressing methods are used. Not adopted. Therefore, the rubber roller is rotatably arranged so as to face a heating means such as an infrared heater and is constantly heated to a predetermined temperature.

[0007]

However, the method of transferring the transfer foil to the work surface by the rubber roller is difficult when the work surface is complicated as described above, and therefore, a slightly complicated curved surface shape or three-dimensional shape is required. In the case of a work having a shape, there is a disadvantage that it cannot be processed.

Therefore, even if the vacuum pressing method is adopted as it is, the outer surface temperature of the elastic cover is often different from the temperature control set temperature, for example, by about 50 ° C. This depends on the work speed and the room temperature of the workplace.

Further, the temperature uniformity in the effective use area of the elastic cover is poor, and the central portion and the peripheral portion have a temperature of about 30 ° C to 50 ° C.
There may be a difference.

Further, the temperature of the elastic cover is such that heat is applied to the work within a range of about 30 to 180 seconds in one operation.
After the completion of one work, the temperature will drop from about 40 ℃ to 60 ℃, so it is necessary to recover to the required temperature before the next work.
In the conventional device, the heating time was too long and the work was often awaited.

Thus, in the conventional vacuum pressing method, since it is difficult to properly control the temperature required for thermal transfer, there are disadvantages that defective products are formed or mass productivity is poor.

In view of the above circumstances, the present invention provides a method and an apparatus for enabling a thermal transfer which requires a uniform high temperature on a work by a vacuum pressing method.

[0013]

According to a curved surface vacuum press thermal transfer method of the present invention, a work having a curved surface shape and a film for surface processing are housed in a decompression chamber and an upper part thereof is covered with a lid body. The elastic cover stretched over the opening of the body is heated by the internal heating element to decompress the decompression chamber,
By pressurizing the inside of the lid, the elastic cover deforms and conducts heat to adhere the film to the work. After the film adheres to the work, the lid is separated from the decompression chamber and the work is completed after one work is completed. It is characterized in that the elastic cover is brought into contact with or brought close to an external heating body heated to a predetermined temperature before the start of the work.

Further, the curved surface vacuum press thermal transfer apparatus according to the present invention is provided with a decompression chamber connected to a vacuum pump, a work having a curved surface shape which is movably and communicably placed on the decompression chamber, and its surface processing. A pressure reducing table for accommodating a film and an elastic cover for sealing the pressure reducing table are stretched over the opening, and an internal heating element whose temperature is controlled by a temperature sensor is provided close to the elastic cover. It is characterized by comprising a lid body that can be raised and lowered and a movable external heating body that comes into contact with the elastic cover when the lid body moves up and the decompression table moves, and whose temperature is controlled by a temperature sensor.

Further, the curved surface vacuum press thermal transfer apparatus according to the present invention is provided with a decompression chamber connected to a vacuum pump, a work having a curved surface shape movably and communicably placed on the decompression chamber, and its surface processing. A decompression table to store the film and an elastic cover that seals the decompression table are stretched over the opening, and an internal heating element whose temperature is controlled by a temperature sensor and a metal net for heat dispersion are elastic. A lid body that can be moved up and down in the vicinity of the cover body and that can compress the inside,
It is characterized in that it comprises a movable external metal heating element that comes into contact with the elastic cover when the lid is raised and the decompression table moves and the temperature is controlled by a temperature sensor.

[0016]

The elastic cover is always heated by the internal heating body during the working work, and even if one work is completed and the surface temperature is lowered, the elastic covering body is further heated in contact with the external heating body. Therefore, 1
Since the heat lost during the work is recovered in a short time to reach the predetermined temperature, the work cycle time is shortened and the efficiency is improved.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described based on the illustrated embodiments. As shown in FIGS. 1 and 2, a decompression chamber 2 is formed by a box-shaped decompressor 1 which is maintained at a predetermined height from the floor surface, etc., and a vacuum pump 3 for decompressing the decompression chamber 2 and its piping are provided. Slide rails 4 and 4 are provided on the left and right edges of the decompressor 1, and a decompression table 5 is mounted on the slide rails 4 and 4 so as to be movable in the depth direction of FIG.

The decompression table 5 has a box shape similar to that of the decompression machine 1, and has a gasket 6 attached to the edge thereof and a large number of through holes 7 formed at the bottom. A shallow box-shaped receiving jig 8 made of a breathable material is placed inside the decompression table 5, and a work 9 is placed inside the receiving jig 8.
The transfer foil 10 is placed on the upper part of the work 9 so as to cover the receiving jig 8. The moving operation of the decompression table 5 may be performed by pushing or pulling it manually or automatically using power.

An external heating element 11 is movably mounted on the slide rails 4 and 4 together with the decompression table 5. The external heating body 11 has a heating body 14 such as an electric heater built in a space 13 formed by metal blocks 11a and 11b such as aluminum which are divided into upper and lower parts with a heat insulating material 12 interposed therebetween. A temperature sensor 16 which is connected to an appropriate power source through 15 and is built in the metal block 11a.
Is heated and maintained at a predetermined temperature. The external heating element 11
In addition to a metal block that is internally heated, a heater that irradiates the elastic cover 21 with far infrared rays may be used instead.

Further, a lid 17 is arranged above the decompression table 5 so as to be able to move up and down. The lid 17 has a box shape similar to that of the decompression table 5, and a supporting rod 18, 1 such as a cylinder is provided above the lid 17.
It is provided so as to be able to move up and down through fixing portions 19, 19 that connect 8 and guide the support rods 18, 18 up and down. An elastic cover 21 that covers the compression chamber 20 formed inside the lid 17 is stretched around the opening, and inside the compression chamber 20 is close to the elastic cover 21 and internal heating such as an electric heater is performed. A body 22 is provided, and a heat-dispersing metal net 23 is provided near the elastic cover 21. The internal heating body 22 is connected to an appropriate power source via a wiring 24, comes into contact with the elastic cover body 21, and is heated and maintained at a predetermined temperature by a temperature sensor 25 incorporated in the compression chamber 20.

Further, a press-fitting pipe 26 is provided at a substantially central portion of the lid body 17.
Are connected, and the press-fitting pipe 26 is connected to the compressed hot air tank 27. The compressed hot air tank 27 has an internal heating body 28 such as an electric heater built therein, the internal heating body 28 is connected to an appropriate power source through a common wiring 24, and a built-in temperature sensor 29 keeps the temperature at a predetermined temperature. It further,
A compression pump 30 is connected to the compression hot air tank 27, and the compression pump 30 supplies compressed air to the compression hot air tank 27. The lifting and lowering operation of the lid body 17 is performed using a cylinder that moves the support rod 18 up and down using a hydraulic device as a drive source.

To explain the operation of the above embodiment, the heating elements 14, 22, 28 are operated to heat the external heating element 11 and the compression chamber 20 to a predetermined temperature. The heating element 14 heats the external heating element 11 from the inside to maintain a predetermined temperature, the internal heating element 22 heats the heat dispersion metal net 23 and the inside of the compression chamber 20 by radiant heat, and the heat dispersion metal net 23 is While heat-dispersing the atmosphere inside the compression chamber 20 to a uniform temperature,
The internal heating body 28 heats the compressed air supplied to the compressed hot air tank 27 with radiant heat, and the compressed air is supplied into the compression chamber via the press-fitting pipe 26.

Therefore, the decompression table 5 is pulled out from the decompression device 1 to the operator side, the work 9 is placed on the receiving jig 8, and the transfer foil 1 is transferred.
When the preparation for the thermal transfer work is completed by covering the receiving jig 8 with 0, the decompression table 5 is moved to the lower part of the lid body 17 and the transfer foil 10 and the elastic cover body 21 are opposed to each other. Then, as shown in FIG. 3, the lid body 17 is moved down, the lid body 17 and the decompression table 5 are brought into close contact with each other and sealed with the gasket 6, and the vacuum pump 3 is activated to bring the decompression chamber 2 into a vacuum state. Further, by operating the compression pump 30 to pressurize the compression chamber 20, the elastic cover 21 comes into contact with the transfer foil 10 and conducts heat to the elastic cover 21 to deform along the curved surface or the three-dimensional shape of the work 9, The transfer foil 10 is pressed against the work 9.

Thus, when one work is completed after the time required for thermal transfer to the work of a predetermined shape has passed, the operation of the vacuum pump 3 is stopped, the lid 17 is raised, and the decompression table 5 is moved.
Away from, and pull out the decompression table 5 to the operator side again,
As shown in FIG. 4, the external heating body 11 is moved to the lower part of the lid body 17 and the elastic cover body 21 is brought into contact with the surface thereof (when a far infrared heater is used as the external heating body 11, it is brought close to it). As a result, the elastic cover 21 receives the heat deprived of the work 9 and the transfer foil 10 in order to recover the heat.
It is heated to a predetermined temperature by the internal heating element 22 and the internal heating element 22.

Then, the work 9 is placed on the receiving jig 8 on the decompression table 5 again, and the receiving jig 8 is covered with the transfer foil 10. Then, the decompression table 5 is pushed back in the same manner as described above, and as shown in FIG. Then, thermal transfer processing is performed in the same manner as above. In this way, the work 9
Since the elastic cover 21 is in contact with the external heating body 11 and is constantly maintained at a predetermined temperature during setting of the workpiece or removal of the workpiece 9 and setting of a new workpiece, a situation occurs in which the heat required for thermal transfer is insufficient. And therefore always good thermal transfer.

In the above-mentioned embodiment, the case of vacuum press thermal transfer using a transfer foil is explained, but it is obvious that the present invention is not limited to this and can also be applied to conventional vacuum press laminating.

[0027]

According to the present invention described above, since the elastic cover is heated by the internal heating element, the heat lost after the completion of one operation is recovered from the external heating element.
The high temperature can be reached in a short time, and the work cycle speed can be increased.

Further, the elastic cover can suppress the difference between the indicated temperature and the actual temperature within ± 10 ° C. due to the combined effect of the internal heating element and the external heating element and the function of the temperature sensor. Since it is designed to be heated by both the external heating element and the external heating element, it is possible to use a rubber sheet that is 2 to 3 times thicker than the conventional one, and the heat storage amount of the thick rubber sheet is twice that of the conventional one. As described above, the work time can be dramatically reduced.

Since the external heating element is made of metal,
Since the thermal stability in the effective use range is very good, the elastic cover is brought into contact with the heat to heat it, so that the heat is directly conducted and the temperature difference is minimized.

Further, since the internal heating element can be provided close to the elastic cover and the heat can be dispersed up to the periphery by the metal net heated by the internal heating element, the ambient temperature within the effective use area can be improved. Uniformity is improved.

Since the transfer foil can be thermally transferred to the work by the vacuum pressing method, good surface processing can be performed even when the work is somewhat complicated, which cannot be done by the conventional rubber roller. Since there is no need to apply adhesive to the foil, there is the advantage that no means of spraying adhesive is needed.

[Brief description of drawings]

FIG. 1 is a sectional front view of an embodiment of the present invention showing a state before a transfer operation.

FIG. 2 is a sectional front view of the embodiment of the present invention showing a state after a transfer operation.

FIG. 3 is a side view illustrating the operation.

FIG. 4 is a side view illustrating the operation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Decompressor 2 ... Decompression chamber 3 ... Vacuum pump 4 ... Slide rail 5 ... Decompression stand 7 ... Through hole 8 ... Receiving jig 9 ... Work piece 10 ... Transfer foil 11 ... External heating body 14 ... Heating body 16 ... Temperature sensor 17 ... Lid 18 ... Support rod 20 ... Compression chamber 21 ... Elastic cover 22 ... Internal heating body 23 ... Heat dispersion metal net 25 ... Temperature sensor 30 ... Compression pump

Claims (3)

[Claims] 1. A work having a curved surface shape and a film for surface-treating the work are housed in a decompression chamber, an upper portion is covered with a lid, and an elastic cover stretched over an opening of the lid is internally heated. By heating the inside of the decompression chamber by depressurizing it and pressurizing the inside of the lid, the elastic cover deforms and conducts heat to adhere the film to the work.After the film adheres to the work, depressurize the lid. A curved surface vacuum press thermal transfer method, characterized in that the elastic cover is brought into contact with or brought close to an external heating body heated to a predetermined temperature after the end of one work after the separation from the chamber and the start of the next work. 2. A decompression chamber connected to a vacuum pump, a decompression table for accommodating a work having a curved surface shape movably and communicably placed on the decompression chamber and a film for surface processing thereof. An elastic cover that seals the decompression table is stretched over the opening, and an internal heating body that is internally temperature-controlled by a temperature sensor is provided in the vicinity of the elastic cover so that the lid can move up and down.
A curved surface vacuum press thermal transfer device comprising a movable external heating body that comes into contact with an elastic cover when the lid moves up and the decompression table moves and the temperature is controlled by a temperature sensor. 3. A decompression chamber connected to a vacuum pump, a decompression table for movably and communicatively mounted on the decompression chamber and having a curved surface and a film for processing the surface thereof. An elastic cover that seals the decompression table is stretched over the opening, and an internal heating element whose temperature is controlled by a temperature sensor and a metal net for heat dispersion are provided in the vicinity of the elastic cover and can be moved up and down, and It consists of a lid that can be compressed inside, and a movable metal outer heating element that comes into contact with the elastic cover when the lid rises and the decompression table moves, and whose temperature is controlled by a temperature sensor. Characteristic curved surface vacuum press thermal transfer device.