JP5549036B2 - Vacuum forming method - Google Patents

Description

  The present invention relates to a vacuum forming machine for forming a sheet material on a adherend in a vacuum state, a substrate for a vacuum forming machine used in a vacuum forming process using the vacuum forming machine, or such a vacuum forming machine. The present invention relates to a vacuum forming method using an industrial substrate.

  2. Description of the Related Art Conventionally, as a vacuum forming apparatus that is not easily affected by outside air, a vacuum forming apparatus that has a chamber box at the top and bottom and that performs molding of an object to be molded 1 in both chamber boxes, an upper chamber box and a lower chamber box. In addition, a heater is incorporated in the upper chamber box and the object to be molded is heated by the heater in both the joined chamber boxes (see Patent Document 1). ).

  This means that the object to be molded is heated by the heater in both the bonded chamber boxes, and the object to be molded can be heated and molded in a closed space by using a near infrared heater as the heater. Therefore, it is possible to provide a vacuum forming apparatus that is less susceptible to the influence of outside air than before when forming.

Japanese Patent Application Laid-Open No. 2002-079573

  However, in the above conventional vacuum forming apparatus, if the pressure is released while the cooling is insufficient, there is a problem that product defects such as floating of the decorative film are likely to occur. For this reason, it took time to cool the heated decorative film after molding, and it was not possible to efficiently perform vacuum molding by shortening the cooling time of the decorative film or molding device after molding.

  Therefore, the present invention has an object to reduce the cooling time of a decorative film or a molding apparatus after molding and efficiently perform vacuum molding in a vacuum molding method in which a decorative film is closely adhered and molded under reduced pressure conditions. To do.

(1) The vacuum forming method of the present invention uses a vacuum forming machine in which the molding space S can be hermetically formed by the lower box 21 opened in the lower portion and the upper box 22 opened in the upper portion, and the deposition in the molding space S is performed. A vacuum forming method in which a decorative film F is closely attached to the surface of a body W and molded,
A placement step of setting the vacuum molding machine substrate 1 on the movable table 3 installed in the lower box 21 and placing and placing the adherend W on the housing portion of the vacuum molding machine substrate 1;
The molding space S is divided up and down with the decorative film F installed so as to close the opening between the lower box 21 and the upper box 22 above the adherend W, and the table 3 is placed in the lower molding space S. A sealing process for sealing the vacuum molding machine substrate 1 and the adherend W;
A heating step of heating the decorative film F installed in the sealed molding space S;
The lower molding space S sealed by the sealing process was depressurized with respect to the upper molding space S to generate a pressure difference in the molding space S partitioned by the decorative film F, and set on the table 3. A pressure adjusting step in which the vicinity of the surface of the adherend W is set to an environment in which the pressure is reduced from the surroundings;
Molding in which the decorative film F is closely formed on the surface of the adherend W by bringing the table 3 on which the adherend W is placed by the placing step from the lower side of the decorative film F heated by the heating step. Process,
A pressure releasing step for releasing the pressure difference generated by the pressure adjusting step after the molding step;
And a step of releasing the sealed state of the molding space after the pressure releasing step and taking out the molded product FW,
After the molding step, but before the pressure release step, there is a pressure cooling step of sealing the cooling gas C in the upper molding space while maintaining the pressure difference generated by the pressure adjustment step.

(2) In the above vacuum forming method,
In the pressure adjusting step, a decompression step for decompressing the upper and lower molding spaces S partitioned by the decorative film F covering the adherend W, and a pressure state by pressurizing only the upper molding space S after the decompression step. A pressurizing step to maintain
The heating step is for heating the decorative film F from the upper molding space S in the decompression step,
In the molding step, it is preferable that the decorative film F is covered on the adherend W by raising the table 3 from the lower molding space S in the pressurizing step.

(3) In the pressurizing and cooling step of any one of the above vacuum forming methods, the substrate 1 for the vacuum forming machine and the adherend W in the forming space S are formed from the ejection ports (51, 52) provided in the upper box 22. The cooling gas C (cooled compressed air in the embodiment) having a predetermined ejection volume is ejected toward the outside, and the same volume as the ejection volume of the cooling gas C from the discharge port provided in the upper box 22 to the outside of the upper box 22. Alternatively, it is preferable to cool while maintaining the pressure in the upper molding space S at a high pressure by discharging the air in the upper molding space S having the same volume or less.

  In particular, the cooling gas C is jetted from the jet ports 51 and 52 provided on any of the inner surfaces of the upper box 22 to the vacuum molding machine substrate 1 and the adherend W in the upper molding space S. The discharge port is provided in a portion of the inner surface of the upper box 22 except for the vicinity of the outlets 51 and 52 of the cooling gas C and the region to which the cooling gas C is discharged, so that the cooling efficiency due to the injection of the cooling gas C is not hindered. It is preferable to discharge from

(4) In any one of the above vacuum forming methods, the upper box 22 is provided with a plurality of heating elements 230 for heating the decorative film F in a predetermined arrangement region on the inner surface of the box. At the same time, it is preferable that the ejection ports 51 and 52 for ejecting the cooling gas C are provided in the arrangement region of the heating element 230.

  In particular, it is preferable that the heating element 230 is arranged in a predetermined arrangement area on the inner surface of the box, and two or more of the jet nozzles 51 and 52 are arranged to be dispersed in the arrangement area. Is preferred. For example, the upper box 22 is arranged in rows and columns in the upper surface of the upper box 22 and the outlets 51 and 52 are arranged in a distributed manner between rows or columns near the center except for the four corners of the heating elements arranged in the matrix. The

(5) In the pressure cooling step of any one of the above vacuum forming methods, air or air constituent gas is circulated between the upper forming space S and the circulation pipe via the cooling compressor 5C. It is preferable to continuously enclose the cooling gas C and discharge the air in the molding space S for a predetermined pressurized cooling time.

  By taking the above measures, in the vacuum forming method in which the decorative film is formed in close contact under reduced pressure conditions, the cooling time of the decorative film or the molding apparatus after molding can be shortened to efficiently perform vacuum forming. It became possible.

Explanatory drawing of the basic composition of the vacuum forming apparatus of Example 1 in a mounting process. Each state explanatory drawing of the mounting process thru | or a molding process of the vacuum forming method of Example 1. FIG. Each state explanatory drawing of the process after the pressurization cooling process of the vacuum forming method of Example 1. FIG. The piping diagram of the pressurization cooling process of the vacuum forming apparatus of Example 1. FIG. FIG. 6 is an air circuit diagram of the vacuum forming apparatus of Example 2. The bottom view of the upper box which shows the upper surface in the upper box of the vacuum forming apparatus of Example 2. FIG. FIG. 6 is a piping diagram of a pressure cooling process of the vacuum forming apparatus of Example 3.

Hereinafter, it demonstrates with each process drawing of the vacuum forming apparatus shown as Examples 1-3 as a form example for implementing this invention. The vacuum forming method of the present invention basically uses a vacuum forming machine in which a closed forming space or an open state is formed by a lower box and an upper box which are close to or away from each other, and a decorative film is formed on the surface of an adherend. Is made to adhere. In any of the embodiments, the following steps are included (the numbers in parentheses at the beginning correspond to the respective step diagrams of FIGS. 2 and 3).
(1) (2) Placement step (3) of setting a substrate for a vacuum molding machine on a movable table 3 installed in a lower box and placing and placing an adherend on a housing portion of the substrate for a vacuum molding machine. ) Sealing process for partitioning the molding space up and down with the decorative film as a boundary, and sealing the table, the substrate for vacuum forming machine and the adherend in the lower molding space (4) Heating process for heating the decorative film (4) (5) The lower molding space sealed by the sealing step is decompressed with respect to the upper molding space to generate a pressure difference in the partitioned molding space, and the vicinity of the surface of the adherend set on the table is observed. The pressure adjustment process (5) which makes it a depressurization environment rather than the circumference | surroundings From the lower part of the decoration film heated by the said heating process, the table which mounted the to-be-adhered body by the said mounting process, and the heated decoration film were made to adjoin Decorate the surface of the adherend (6) Pressurized cooling in which cooling gas is sealed in the upper molding space while maintaining the pressure difference generated by the pressure adjusting step after the molding step and before the pressure releasing step. Step (7) Pressure release step (8), (9), (10) Release the pressure difference generated by the pressure adjustment step after the molding step.

(Pressure adjustment process)
The pressure adjusting step includes a pressure reducing step for reducing the pressure in the upper and lower molding spaces partitioned by the decorative film covering the adherend, and a pressure step for pressurizing only the upper molding space after the pressure reducing step.

  A heating process heats a decorating film from the upper shaping | molding space in the former pressure reduction step. In the molding step, the decorative film is placed on the adherend by raising the table from the lower molding space in the latter pressure step.

(Pressurized cooling process)
In the pressure cooling step, a cooling gas of a predetermined ejection volume is ejected from the ejection ports (51, 52) provided in the upper box toward the vacuum molding machine substrate and the adherend in the molding space, and the upper box. Cooling while maintaining the pressure in the upper molding space by discharging the air in the upper molding space that is the same volume or less than the volume of the cooling gas to the outside of the upper box from the outlet provided inside .

  In particular, the cooling gas is jetted from a jet port provided on one of the inner surfaces of the upper box toward the vacuum molding machine substrate and the adherend in the upper molding space, and the discharge port is the inner surface of the upper box. Among these, it is preferable to discharge from a position that is provided in the vicinity of the jet port of the cooling gas and in a region excluding the jet destination and does not hinder the cooling efficiency due to the jet of the cooling gas.

  In the pressurization and cooling process of the first embodiment shown in FIGS. 3 and 4 and the pressurization and cooling process of the second embodiment shown in FIG. 5, pressurization is applied to the pressurization and cooling pipe 5 connected to the upper portion of the upper box. A cooling valve 5V and a cooling compressor 5C are provided, and compressed air is supplied by pressure from an air tank PT connected upstream of the cooling compressor 5C by jetting, and an exhaust pipe connected in communication with the side of the upper box. 6, the air in the upper molding space is opened to the outside from the front portion 6R, and is forcedly exhausted by the pressurized supply of the compressed air.

  Since the non-circulation type one-way sealing and one-way discharging are performed, the cooling rate is shortened by always ejecting fresh compressed air to the adherend. Further, at this time, the discharge amount from the discharge port is reduced to less than half of the pressurized flow rate (more preferably, one third or less) by the adjuster 6R provided in the exhaust pipe, and the discharge from the discharge port By continuously adjusting the amount by the pressure cooling valve 5V, it is possible to maintain the pressurized state of the upper molding space.

  In the pressurization and cooling process of Example 3 shown in FIG. 7, the cooling gas is sealed and formed by circulating air or an air constituent gas in the upper forming space and the circulation pipe through the cooling compressor. The discharge of the internal air is continued at the same time for a predetermined pressure cooling time.

(Upper box)
In the upper box, a plurality of heating elements (230) for heating the decorative film are dispersed and arranged in a predetermined arrangement area on the inner surface of the box, and between the arrangement areas of the heating elements, Jet ports (51, 52) for jetting the cooling gas are provided.

  In particular, the heating element 230 is preferably arranged in alignment with a predetermined arrangement area on the inner surface of the box, and two or more jet nozzles are preferably arranged in the arrangement area. For example, the upper box is arranged in rows and columns in the upper surface of the upper box, and the outlets are arranged in a distributed manner between rows or columns near the center except for the four corners of the heating elements arranged in the row.

  The lower box opened to the lower part and the upper box opened to the upper part are brought into a closed state in which a closed molding space is formed or an open state in which the air is released, by mutual contact or separation of the openings by relative movement.

  As another method for cooling the inside of the upper molding space while maintaining the adjustment pressure in the upper and lower molding spaces, it is possible to pressurize and seal the compressed air from the outlet through the cooling compressor while opening the discharge port to the outside. Conceivable. By adjusting the amount of cooling air ejected from the outlet and shifting the opening timing of the outlet and the pressure filling timing of the cooling air from the outlet, the pressurized state in the upper molding space can be maintained. it can.

(Frame part)
In addition, in the molding process, a frame portion protruding in the proximity direction of the decorative film at a protruding height higher than the maximum height of the adherend is provided on the outer periphery of the set adherend,
The frame part comes into contact with the decorative film prior to the adherend, and the frame part is in a contact state where the decorative film is pushed up and stretched outside the adherend,
It is preferable that the adherend adheres to the surface of the stretched decorative film after the frame portion contact state.

  In this case, in the vacuum forming machine that molds the decorative film in close contact with the surface of the adherend by making the vicinity of the surface of the adherend set on the table a reduced pressure environment and bringing the heated decorative film close to the surface. A frame that protrudes in the proximity direction of the decorative film at a protruding height higher than the maximum height of the adherend is provided outside the periphery of the set adherend, and the frame closes the decorative film. When making it adhere, it contacts with a decorating film ahead of a to-be-adhered body, and is set as the state which pushed up the decorating film around the to-be-adhered body, and was extended.

The frame portion comprises a side frame member fixed by surrounding the outer peripheral portion of the bottom plate on which the adherend is placed in a polygonal shape,
The side frame material has an inner inclined surface inclined toward the center of the polygonal shape on the inner side of the frame at least at all corners constituting the polygonal shape.

  The substrate for a vacuum forming machine that is detachably installed on the table of the vacuum forming machine is fixed along the periphery of the bottom plate with a bottom plate having a housing portion on which an adherend can be placed near the center of the upper surface, It is preferable that the frame portion is composed of a side frame material that surrounds the outer periphery of the adherend at a frame height higher than the maximum height of the adherend accommodated on the bottom plate, and the frame portion is constituted by the side frame material. .

  In addition, since the present invention is provided with a heater composed of a plurality of heating elements aligned on the inner surface of the upper box, it is a vacuum forming apparatus that is not easily affected by outside air. In addition, the present invention is not limited to the above-described embodiments, and within the scope of the present invention, extraction of some elements, replacement with elements or substitutes of other embodiments, deletion, or configurations between the embodiments Various modifications such as a superimposing combination of the above are possible.

DESCRIPTION OF SYMBOLS 1 Substrate for vacuum forming machines 21 Lower box 22 Upper box 3 Table C Cooling gas F Decorating film S Molding space W Substrate 51, 52 Spout 5C Cooling compressor

Claims (4)

Vacuum molding in which a decorative film is brought into close contact with the surface of the adherend in the molding space using a vacuum molding machine in which the molding space can be hermetically formed by a lower box opened at the bottom and an upper box opened at the top. A method,
A mounting step of setting a substrate for a vacuum molding machine on a movable table installed in a lower box, and mounting and housing an adherend in a housing portion of the substrate for a vacuum molding machine;
A sealing process that partitions the molding space up and down with the decorative film as a boundary, and seals the table, the substrate for the vacuum molding machine, and the adherend in the lower molding space;
A heating step for heating the decorative film;
The lower molding space sealed by the sealing process is decompressed with respect to the upper molding space to generate a pressure difference in the partitioned molding space, and the vicinity of the surface of the adherend set on the table from the periphery The pressure adjustment process to make the pressure reduced environment,
From below the decorative film heated by the heating step, the table on which the adherend is placed by the placing step and the heated decorative film are brought close to each other and the decorative film is tightly formed on the surface of the adherend. Molding process;
A pressure releasing step for releasing the pressure difference generated by the pressure adjusting step after the molding step;
A process of taking out the product together with releasing the pressure,
Wherein even after molding step before pressure releasing step, have a pressurized cooling step of enclosing a cooling gas to the top of the molding space while maintaining a pressure differential generated by the pressure adjusting step,
The pressure adjusting step includes a depressurizing step for depressurizing the upper and lower molding spaces partitioned by a decorative film covering the adherend, and a pressurizing step for pressurizing only the upper molding space after the depressurization step. ,
The heating step is to heat the decorative film from within the upper molding space in this decompression step,
The molding process, a vacuum molding method, characterized in der Rukoto those covered with the decorative film raises the table from the bottom of the molding space on an adherend in the pressurizing step. In the pressurization and cooling step, a cooling gas having a predetermined ejection volume is ejected from the ejection port provided in the upper box toward the vacuum molding machine substrate and the adherend in the molding space, and is provided in the upper box. The cooling is performed while maintaining the pressure in the upper molding space by discharging the air in the upper molding space having the same volume or less than the ejection volume of the cooling gas from the discharge port to the outside of the upper box. Vacuum forming method. In the upper box, a plurality of heating elements for heating the decorative film are dispersed and arranged in a predetermined arrangement area on the inner surface of the box, and cooling gas is introduced into the arrangement area of the heating elements. The vacuum forming method according to claim 2, wherein a jetting outlet is provided. In the pressurization and cooling step, the gas is circulated between the upper molding space and the circulation pipe through the cooling compressor, thereby continuously enclosing the cooling gas and discharging the air in the molding space. The vacuum forming method of any one of.

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