JP2001009901A - Structure of film mold in deep-draw vacuum packaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the reduction ratio of the wall thickness of the bottom corner R-part of an article housing recessed part by gradually increasing the inner dimension of the molding recessed part of the film mold provided in a molding box from the opening end of the molding recessed part to the bottom part thereof in order to form the article housing recessed part to a lower film in a deep-draw vacuum packaging apparatus. SOLUTION: A molding box 13 is allowed to communicate with a vacuum source through the through-hole 20 provided to the lower corner part of the molding box 13 and a forming stand 22 is placed on the receiving stand of the inner bottom surface of the molding box 13. The forming stand 22 can be divided into two parts and the side walls 24a four in total of the formed molding recessed parts 23 having a circular shape on a plan view are gradually expanded downward to be connected to the horizontal bottom parts of the recessed parts 23 through bottom corner R-parts. A lower film is heated and softened by a molding bridge 10 and, thereafter, the molding box 13 communicates with the vacuum source and the molding recessed parts 23 are reduced in pressure through the small hole of the receiving stand or forming stand 22 to suck the film downward. By this constitution, the wall thickness reducing ratio of the bottom corner R-part of an article housing recessed part can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a structure of a film forming die in a deep drawing vacuum packaging apparatus.

[0002]

2. Description of the Related Art In a conventional deep drawing vacuum packaging apparatus, as shown in FIG. 8, an article A is formed on a film 1 by a forming part A while a lower film 1 is pulled out from a raw material 2 and is intermittently fed forward. The storage recess 3 is formed, and products such as ham are supplied to the article storage recess 3 from above in the product supply section B. Thereafter, the upper film 4 is pulled out of the web 5 and sent to the vacuum section C so as to cover the article storage recess 3 of the upper film 4, where the air between the upper and lower films is sucked and the article storage is performed. Several containers 6 which are heat-sealed to each other at the periphery of the concave portion 3 and are sealed are formed. Next, the space between the containers adjacent to the front and rear is cut in the horizontal direction by the horizontal cutter device 7, and further, the space between the containers and the containers adjacent in the horizontal direction is cut in the front by the vertical cutter device 8 in the vertical direction. Each package is obtained.

[0003] The present invention relates to an improvement of a molding part A for forming the article storage recess 3 in the lower film 1 in the deep drawing vacuum packaging apparatus as described above.
Is shown in That is, in the forming portion A, a box body called a forming bridge 10 is fixedly provided adjacent to above the lower film 1, and a hot plate 11 is housed inside the forming bridge 10. The lower surface is flush with the lower open end surface of the forming bridge 10. A large number of small holes 12 are formed in the hot plate 11 so as to penetrate vertically, and the space in the forming bridge 10 above the hot plate can communicate with a vacuum source via a valve (not shown). I have.

Below the lower film 1, a forming bridge 1 is provided.
A molding box 13 is provided at a position opposite to the position 0 so as to reciprocate up and down. A forming table 15 functioning as a film forming die is housed inside the forming box 13, and a forming recess 14 is formed in the forming table 15. A number of small holes 16 are formed below the forming recess 14 through the forming table 15, and these small holes 16 communicate with a vacuum source through the bottom of the forming box 13 through a passage not shown. It is supposed to be.

[0005] With the above structure, the lower film 1
When the intermittent movement of the lower film 1 is stopped, the forming box 13 is raised to sandwich the film 1 with the forming bridge 10. Next, a negative pressure is applied to the inside of the forming bridge 10, the lower film 1 comes into close contact with the hot plate 11, and the film is heated and softened. When the film is softened, the negative pressure inside the forming bridge 10 is released, and at the same time, the forming box 13 is connected to a vacuum source by switching a valve. As a result, a negative pressure is applied to the molding box 13.
, The negative pressure passes through the small holes 16 of the forming table 15 to create a negative pressure in the molding recess 14. As a result, the lower film 1 is formed on the forming table 1 by the suction force of the negative pressure.
5 to form the article storage recess 3. Next, the negative pressure is released and the molding box 13 descends. Then, the lower film 1 is further advanced by one pitch and stopped, and the above steps are repeated.

[0006]

In the structure of the conventional molding portion A as described above, since the inner peripheral wall of the molding recess 14 is formed as a vertical wall except for the bottom corner round portion, the article storage recess 3 is formed. When vacuum pressure is applied to the molding recess 14 in order to vacuum-mold the film 1, the film 1 is adsorbed from the bottom center of the recess toward the outer periphery of the bottom as shown in FIGS. 10 (b) and 10 (c), and then (d). As shown in ()), the film is sucked on the upper peripheral portion of the side wall of the concave portion 14, then the sucked portion on the side wall gradually moves down as shown in (e), and finally the film is sucked on the bottom corner radius. You. Since the forming table 15 defining the forming recess is cooled, the film adsorbed on the side wall in the initial stage of the vacuum forming is no longer stretched as shown in FIG. In the step (e), only the film portion facing the bottom corner radius portion is relatively greatly stretched, and the bottom corner radius portion is considerably thinner than the initial thickness of the film, and this portion is the thinnest portion of the film. Part. For this reason, in practice, the thickness of the film to be used is determined based on the thickness of the bottom corner radius portion after molding.

The present invention is based on the fact that the bottom corner radius is thinnest as described above, and its object is to reduce the reduction rate of the thickness of the bottom corner radius of the article storage recess. The aim is to provide a film forming die in a deep drawing vacuum packaging device that can reduce the thickness of the film used than before, thereby improving economic effects and contributing to global resources and environmental protection. .

[0008]

In order to achieve the above-mentioned object, the present invention provides a forming recess of a film forming die installed in a forming box for forming an article storing recess in a lower film by a deep drawing vacuum packaging apparatus. The inside size of the place is gradually increased from the opening end to the bottom. Preferably, the inner wall of the recess is inclined at an angle of 3 to 6 degrees with respect to the vertical plane.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The structure of a forming section A according to the present invention will be described with reference to FIG. 1. Since a forming bridge 10 located above a lower film is the same as the conventional example, a description thereof will be omitted.

A through hole 20 is formed in a lower corner of the molding box 13.
Is formed, and the forming box is communicated with a vacuum source (not shown) through the through hole 20. A receiving table 30 is provided on the inner bottom surface of the molding box 13, and a forming table 22 is placed on the receiving table 30.

As shown in FIG. 2, the forming table 22 can be divided into two parts, and a total of four plane circular forming recesses 23 are formed. As shown in FIG. 3, the side wall 24a of each molding recess 23 gradually spreads downward, and is connected to a horizontal bottom 24c through a bottom corner radius 24b. The bottom corner radius portion 24b of each molding recess 23 has a diameter of 0.
Twenty small holes 25 of about 3 to 0.5 mm are formed at equal intervals, and the lower end of each small hole 25 is formed through a vertical hole 26 having a diameter of 6 mm and an annular groove 27 which connects the vertical holes in a ring shape. 22 is open at the bottom. In addition, each said molding recess 2
It is preferable that the degree of inclination of the inner wall 3 is within a range of 3 to 6 degrees with respect to the vertical plane, as described later.

As shown in FIG. 4, the pedestal 30 can be divided into two, and the upper and lower surfaces of each pedestal 30 are provided with three concave horizontal grooves 31 which cross in a cross shape. Groove 3
2 are formed, and a through hole 33 is formed in the center of the horizontal groove on both sides of each vertical groove 32 so as to vertically penetrate the pedestal.
The outer dimensions of the cradle 30 vertically and horizontally are slightly smaller than the inner dimensions of the molding box 13 both vertically and horizontally. Therefore, an annular void portion 34 is formed between the inner periphery of the molding box and the outer periphery of the pedestal. .

Thus, when the lower film 1 is heated and softened by the forming bridge 10 and the inside of the forming box 13 communicates with the vacuum source by switching the valve, the negative pressure is generated from the vertical and horizontal grooves 31 and 32 on the lower surface of the receiving base 30. The through hole 33 penetrates up and down and the annular gap 34 around the periphery of the cradle 30 reaches the upper surface of the cradle 30, and then extends from the vertical and horizontal grooves 31 and 32 formed on the upper surface of the cradle 30 to the lower surface of the forming table 22. A negative pressure is applied to the inside of the molding recess 23 through the annular groove 27, the vertical hole 26, and the small hole 25 formed in the above, and the film is sucked toward the lower surface thereof.

FIG. 6 shows the process of forming the film at this time. The process up to FIGS. 6B and 6C is almost the same as the conventional case of FIG. 10, but in the case of the present invention, FIG. As shown in FIG. 6D, the film 1 is not adsorbed to the upper edge of the inner wall 24a of the forming recess 23 at the initial stage of vacuum forming.
At the stage (e), there is a gap also above the bottom corner radius portion 24b, and finally, the film is formed while being stretched at the same time to the film located above the bottom corner radius portion. For this reason, the film at the bottom corner radius does not become extremely thin unlike the conventional case.

FIG. 7 shows the specific shape of the molding recess 23.
(A) and (b). In FIG. 7A, the diameter of the circular opening is 97 mm, the depth is 25 mm, and the inclination angle of the inner wall is 3.4 degrees. FIG. 7B shows that the diameter of the circular opening is 94.
mm, the depth is 10 mm, and the inclination angle of the inner wall is 5.7 degrees. From these examples, the inclination angle of the inner wall of the present invention is preferably set to 3 to 6 degrees.

An experimental example of the present invention will be described below in comparison with a conventional example.

[0017]

[Table 1]

The film used was PET / EVOH.
/ NY / easy peel. As is evident from the results of the above experiments, in the present invention, the thickness of the bottom corner radius portion after molding was made the same by using a film 18 μm thinner than the conventional film.
This is, according to a simple calculation, 15.6 than the conventional film.
% Thin films can be used, which can reduce costs and contribute to global resources and environmental protection.

[0019]

As described above, in the film forming die in the deep drawing vacuum packaging apparatus of the present invention, the rate of reduction in the thickness of the bottom corner radius of the article storage recess can be reduced.
As a result, the thickness of the film to be used can be reduced more than before, thereby improving the economic effect and contributing to global resources and environmental protection.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing the structure of a molded part according to the present invention.

FIG. 2 is a plan view showing a forming table used in a forming section of FIG. 1;

FIG. 3 is an enlarged sectional view showing a part of a forming recess formed in the forming table of FIG. 1;

FIG. 4 is a plan view of a cradle used in the molding section of FIG. 1;

FIG. 5 is a perspective view showing one of the receiving stands shown in FIG. 4;

FIG. 6 is an explanatory view showing a state in which a film is molded in the molding recess of the present invention.

FIG. 7 is a side view showing an example of a molding recess of the present invention.

FIG. 8 is a perspective view showing a conventional deep drawing vacuum packaging apparatus.

FIG. 9 is a longitudinal sectional view showing the structure of a conventional molding section.

FIG. 10 is an explanatory view showing how a film is molded in a conventional molding recess.

[Explanation of symbols]

 Reference Signs List A forming part 1 lower film 3 article storage recess 13 forming box 14 forming recess 15 forming table 22 forming table 23 forming recess 24b bottom corner round part 25 small hole 30 receiving table

Claims (2)

[Claims] 1. An inner dimension of a forming recess of a film forming die set in a forming box for forming an article storing recess in a lower film by a deep drawing vacuum packaging apparatus, gradually increasing from an opening end to a bottom. A structure of a film forming die in a deep drawing vacuum packaging apparatus, characterized in that: 2. The film forming die according to claim 1, wherein an inner wall of the forming recess is inclined within a range of 3 to 6 degrees with respect to a vertical plane. Structure.