JPH04102532A - Heat sealing apparatus of lid to container - Google Patents

Abstract

PURPOSE:To prolong the life of a sealing thin plate by providing gaps for letting an elastic body escape between at least one of the outer and inner peripheral edges of an upper elastic body housed in the annular recess of the under surface of a heating and biasing member and the inner peripheral face of the annular recess facing these peripheral edges. CONSTITUTION:In the under surface of the heat transfer aluminum block 2b of the heating and biasing member 2 of a heat sealing apparatus 1, the part expected to bias the container mouth peripheral edge part of a copper thin plate 3 is provided with an annular recess 16 and an annular upper elastic body 4 is housed in the annular recess 16. Gaps 21, 22 for letting an elastic body escape are provided between the outer and inner peripheral edges of the upper elastic body 4 and the inner peripheral face of the annular recess 16. A lid 12 is put on the mouth 11 of a glass container 10, the heated-up heating and biasing member 2 is caused to descend, and the peripheral edge part of the lid 12 is pressed against the top surface of the peripheral edge part of the mouth 11 of the glass container 10 via the copper thin plate 3 and pressed and heated so that the lid 12 is heat-sealed to the mouth 11. Even if the upper elastic body 4 is expanded by a temperature rise, the expanded part is absorbed into the gaps 21, 22 so that the container 10 is heat-sealed surely and no crack occurs in the copper thin plate 3.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION This invention relates to an apparatus for heat-sealing lids for containers such as glass containers.

2. Description of the Related Art In general, glass containers for sealed food packaging have poor finishing precision in the eye area, and minute irregularities are formed on the surface of the circumferential edge. For this reason, a metal foil lid with a heat sealing material layer is placed over the mouth of the glass container, and the heating press member (seal head)
Even when heat sealing was performed using a glass container, the opening of the glass container could not be reliably sealed.

Therefore, conventional heat sealing devices have been proposed in which an upper elastic body (cushion rubber) is interposed between the upper surface of a thin copper plate attached to the lower side of the heating pressing member and the heating pressing member (for example, a special (See Publication No. 62-31373). According to such a conventional device, when the lid is pressed during heat sealing, the upper elastic body can be deformed according to the irregularities on the surface of the circumferential edge of the container, and this causes the heat sealing material layer of the lid to be The lid was pressed by the upper elastic body and reliably entered into the concavities and convexities, and the lid could be brought into close contact with the surface of the mouth periphery of the container, thereby sealing the container.

Problems to be Solved by the Invention However, in conventional heat sealing devices, the upper elastic body is tightly housed in the annular recess provided on the lower surface of the heating and pressing member, so as the temperature of the heating and pressing member increases, When the upper elastic body is heated and expands from the inside of the annular recess to the outside, the thin copper plate is pushed and expands outward. The problem is that the sealing plate becomes large and prone to cracking, and that the expensive copper sealing sheet has a very short service life, making it uneconomical.

An object of the present invention is to solve the above-mentioned problems of the prior art, and even if the upper elastic body expands due to an increase in the temperature of the heating pressing member,
The thin metal plate made of copper or the like is not pushed outward by the upper elastic body, so the amount of deformation of the thin metal plate during heat sealing is small, and the container can be reliably heat sealed. This is an extremely economical lid for containers, which can greatly extend the life of the expensive thin sealing plate, which is generally made of copper, and allow the heat sealing of the mouth of the container to be carried out efficiently over a long period of time. We are trying to provide heat sealing equipment for this purpose.

Means for Solving the Problems In order to achieve the above object, the present invention includes: a heating pressing member; a disc-shaped or annular thin metal plate arranged to be thermally connected to the lower side of the heating pressing member; an upper elastic body housed in an annular recess on the lower surface of the heating pressing member corresponding to the portion of the thin metal plate that is scheduled to be pressed around the container mouth; and an inner elastic body that is attached to the peripheral edge of the heating pressing member and receives the peripheral edge of the thin metal plate from below. In a heat sealing device equipped with a cylindrical mounting member having a receiving portion projecting in the opposite direction, at least one of an outer circumferential edge and an inner circumferential edge of an upper elastic body housed in an annular recess on the lower surface of the heating pressing member, and an opposite side thereof. The gist of the present invention is a heat sealing device for a lid for a container, in which a gap for releasing an elastic body is provided between the inner peripheral surface of an annular recess and the inner peripheral surface of an annular recess.

In the above, the thin metal plate attached to the lower side of the heating pressing member so as to be thermally connected has good thermal conductivity,
Moreover, it is necessary to have appropriate elasticity. Copper is generally used as such a metal thin plate, but other materials such as aluminum, lead, zinc, etc. may also be used.

The thickness of the thin metal plate is approximately 0.05 to 1.0 ms+preferably 0.1 to 0.8 mm. Metal thin plates can be used singly or in layers.

Further, the metal thin plate may be either disc-shaped or annular (ring-shaped).

A width of 0°5 to 21 m is provided between at least one of the outer peripheral edge and the inner peripheral edge of the upper elastic body housed in the annular recess on the lower surface of the heating pressing member and the inner peripheral surface of the annular recess opposite thereto. A gap of a certain size for allowing the elastic body to escape is provided.

Further, a thin metal plate expansion/contraction allowable gap is provided between the peripheral edge of the metal thin plate and the inner circumferential surface of the cylindrical mounting member, and the width of this gap is 0.5 mm when the diameter of the metal thin plate is, for example, about 100 m5. The size is about 5 to 21 Im.

It is preferable that a lower annular elastic body is interposed between the outer circumferential edge of the disc-shaped or annular metal thin plate and the receiving portion of the cylindrical mounting member that receives it.

The upper elastic body is made of synthetic rubber or other elastic material and is heat resistant.

Preferably, these elastic bodies also have thermal conductivity, such as elastic bodies made by kneading metal powder, carbon black powder, metal oxide powder, etc. into rubber as appropriate.

The thickness of the upper elastic body is usually 1 to 5 mm.

Note that the annular lower elastic body is made of synthetic rubber or other elastic material, similar to the upper bow 11i elastic body,
What is necessary is to use a material that is also heat resistant.

On the other hand, the metal foil constituting the lid of the container is usually aluminum foil, but other metal foils may be used. In the case of aluminum foil, its thickness is 20 to 100μ,
Preferably it is 40-60 μl.

In addition, the heat sealing material layer provided on the underside of the lid is made of polyethylene,
Thermoplastic synthetic resins such as ethylene-vinyl acetate copolymers,
Alternatively, it is composed of a composition in which these resins are blended with wax and other compounds in a predetermined ratio. Of course, a polyethine resin layer or the like may be interposed as an adhesion mediating layer between the metal foil and the heat sealing material layer.

According to the heat sealing device described above, there is a gap between at least one of the outer peripheral edge and the inner peripheral edge of the upper elastic body housed in the annular recess on the lower surface of the heating pressing member and the inner peripheral surface of the annular recess opposite thereto. Since the elastic body relief gap is provided, even if the upper elastic body expands due to a rise in the temperature of the heated pressing member, the expanded portion of the elastic body enters the relief gap and is absorbed, so that it does not flow outward. There is no expansion, so the thin metal plate is not pushed by the upper elastic body and bulges outward.

Therefore, the amount of deformation of the thin metal plate during heat sealing is small, and the container can be reliably heat sealed, and the thin metal plate is less likely to crack, making the heat sealing process of the container mouth more efficient over a long period of time. It can be implemented.

Example Next, embodiments of the invention will be described based on the drawings.

In FIGS. 1 and 2 showing the first embodiment of this invention,
The heating pressing member (2) of the heat sealing device (1) is equipped with a heater (
The heat transfer aluminum block (2a) is made up of a heating press member main body (2a) with a built-in heating press member (2a), and an aluminum block attached to the lower end of the body (2a) so that it can be replaced with a required number of bolts (not shown). 2b).

A thin disc-shaped copper plate (3) with a thickness of 0.3 mm is arranged below the heat transfer aluminum block (2b) of the heating pressing member (2), and the peripheral edge of the heating pressing member (2) A cylindrical mounting member (6) having an inwardly projecting receiving portion (7) for receiving the peripheral edge of the disc-shaped thin copper plate (3) from below is attached to the mounting member by a required number of threads 15).

An annular recess (I6) is provided on the lower surface of the heat transfer aluminum block (2b) so as to correspond to the area where the peripheral edge of the container mouth of the thin copper plate (3) is to be pressed. An annular upper elastic body (4) made of rubber and having a thickness of 2IIn is housed inside.

Here, between the outer circumferential edge and the inner circumferential edge of the upper elastic body (4) and the inner circumferential surface of the annular recess (16) facing these, an elastic body escapement with a width of about 0.5 to 2 m is provided. Gap (2
+) (22) is provided.

The central portion and peripheral portion of the lower surface of the aluminum block for heat transfer (2b), excluding the annular recess (1B), are brought into direct contact with the upper surface of the thin copper plate (3), thereby allowing the thin copper plate (3) to conduct heat. aluminum block (2b)
is thermally connected to.

In addition, the peripheral edge of the disc-shaped copper thin plate (3) and the cylindrical mounting member (
8), there is a thin copper plate expansion/contraction allowable gap (20
) is provided. This copper thin plate expansion/contraction allowable gap (20
) is about 0.5 to 2 mm, for example, assuming that the diameter of the thin metal plate is around 100 aun.

Note that an annular lower elastic body (
5) is interposed between the periphery of the lower elastic body (5) and the inner peripheral surface of the cylindrical mounting member (6), and there is also an elastic body relief gap (23) with a width of about 0.5 to 21 mm. is provided.

Glass containers for tightly packaging foods such as jam (10
) A lid (12) is placed over the top of the mouth (11), and this M
(12) is composed of an aluminum foil (13) and a heat sealing material layer (14) provided on the lower surface of the aluminum foil (13).

In the above, in order to tightly wrap the glass container (10) containing the contents, first place the glass container (10) at a predetermined position below the heating pressing member (2) of the heat sealing device (1).
Place the lid (12) on the mouth (11) of this container (10).
cover.

Next, a heated pressing member (
2) is lowered, and a predetermined part near the periphery of the lid (12) is inserted into the opening (1, 0) of the glass container (1, 0) via the thin copper plate (3).
1) Place the lid (12) on the mouth (11) of the glass container (10) by pressing it against the upper surface of the periphery and applying pressure and heat for 2 seconds.
It is heat sealed.

In this case, the outer peripheral edge and inner peripheral edge of the annular upper elastic body (4) housed in the annular recess (18) on the lower surface of the heating pressing member (2), and the annular recess (16) facing these,
) between the inner peripheral surface of the elastic body relief gap (21) (2
2), even if the upper elastic body (4) expands due to a rise in temperature of the heating pressing member (2), the elastic body (
The expanded portion of 4) enters the relief gaps (21, 22) and is absorbed, and does not expand outward beyond the annular recess (16).

Therefore, the thin copper plate (3) is not pushed by the upper elastic body (4) and bulges outward, and the amount of deformation of the thin copper plate (3) during heat sealing is small, and the container (10) is Heat sealing can be achieved reliably, the thin copper plate (3) is less likely to crack, and the heat sealing operation of the opening (11) of the container (10) can be carried out efficiently over a long period of time.

In addition, in this embodiment, there is a gap between the peripheral edge of the disc-shaped thin copper plate (3) and the inner peripheral surface of the cylindrical mounting member (6) having an inwardly protruding receiving part (7) that receives this from below. , the peripheral edge of the annular lower elastic body (5) which receives the lower surface of the outer peripheral edge of the copper thin plate (3), and the inner peripheral surface of the cylindrical mounting member (6), in which a copper thin plate expansion/contraction allowable gap (20) is provided. Since there is also an elastic body escape gap (23) between them, even if the thin copper plate (3) expands due to a rise in temperature of the heating pressing member (2),
Since the expansion is absorbed by the tolerance gap (20), the copper sheet (3) does not bulge outward.

In addition, when the thin copper plate (3) expands, the annular lower elastic body (5) that is in contact with the lower surface of the outer peripheral edge of this thin plate (3) also tries to expand, but the peripheral edge of this elastic body (5) and the cylindrical mounting member (6)
Since the elastic body relief gap (23) is also provided between the inner circumferential surface of It is smooth and the amount of deformation of the copper thin plate (3) is small, and the container (
10) can be reliably heat sealed.

FIG. 3 shows a second embodiment of the invention. Here, the difference from the first embodiment is that the copper thin plate (
3) is annular (ring-shaped), heating pressing member (2)
An outer cylindrical mounting member (6) having an outer receiving part (7) that receives the outer peripheral edge of the annular thin copper plate (3) from below is attached to the outer cylindrical thin plate (3). An inner cylindrical mounting member (
8) is attached by the screw (I7), and between the outer circumferential edge of the annular thin copper plate (3) and the inner circumferential surface of the outer cylindrical mounting member (6), with a width of about 0.5 to 2 ml. A first gap (20a) allowing expansion and contraction of the thin copper plate is provided, and a first gap (20a) having a width of 0.5 to 100 mm is provided between the inner circumferential edge of the annular thin copper plate (3) and the outer circumferential surface of the inner cylindrical mounting member (6). A second gap (2 (lb)) is provided to allow expansion and contraction of the copper thin plate of approximately 21 lbs.

According to this second embodiment, when the annular thin copper plate (3) expands due to the temperature rise of the heating pressing member (2), the expansion is caused by the expansion/contraction allowance nodes 1 and the second gap (2) of the thin copper plate on both the inner and outer sides.
0a) Because it is absorbed by (20b), the thin copper plate (3)
It is possible to reliably heat-seal the container (]0) without causing any outward bulge, and with very few deformation openings of the thin copper plate (3).

In the above embodiment, the outer and inner edges of the upper elastic body (4) housed in the annular recess (16) on the lower surface of the heating pressing member (2) and the current recess (16) facing these
) and the inner circumferential surface of each elastic body relief gap (2
1) (22) is provided, but the elastic body escape gap is formed between at least one of the outer peripheral edge and the inner peripheral edge of the upper elastic body (4) and the inner peripheral surface of the annular recess (16) opposite thereto. It is good if it is provided between.

In addition, in the embodiment, the heating pressing member main body (2a) with a built-in heater and the heat transfer aluminum block (2b) made of an aluminum block attached to the lower end of the heating pressing member main body (2a) so as to be replaceable are used to perform heating pressing. Element(
2), but in some cases the heat transfer aluminum block (2b) may be omitted and a thin copper plate (3
) and the upper elastic body (4) may be directly attached to the heating pressing member main body (2a).

Furthermore, in the embodiment, a case was shown in which the lid (12) was brought into close contact only with the upper surface of the diurnal edge of the glass container (10), but M (
+2) may be brought into close contact with the upper surface of the circumferential edge of the container (10) and the inclined outer circumferential surface of the container (10) to seal the container (10).

Further, in the embodiment, description has been given of heat sealing of a glass container (10), but the apparatus of the present invention is also applicable to other containers, such as containers made of synthetic resin, for example.

Effects of the Invention As described above, the present invention includes a heating pressing member, a disc-shaped or annular thin metal plate arranged to be thermally connected to the lower side of the heating pressing member, and a pressing member for pressing the peripheral edge of the container mouth of the thin metal plate. It has an upper elastic body housed in an annular recess on the lower surface of the heating pressing member corresponding to the scheduled portion, and an inwardly protruding receiving portion that is attached to the peripheral edge of the heating pressing member and receives the peripheral edge of the thin metal plate from below. In a heat sealing device equipped with a cylindrical mounting member, at least one of an outer circumferential edge and an inner circumferential edge of an upper elastic body accommodated in an annular recess on the lower surface of the heating pressing member, and an inner circumferential surface of the annular recess opposite thereto. Since an elastic body relief gap is provided in between, even if the upper elastic body swells due to a rise in temperature of the heating and pressing member, the expanded fat portion of the elastic body enters the relief gap and is absorbed. , does not protrude outward from the annular recess. Therefore, the thin metal plate will not be pushed outward by the upper elastic body, the amount of deformation of the thin metal plate during heat sealing will be small, and the container can be reliably heat sealed. It is less likely to crack and can greatly extend the life of the expensive thin sealing plates, which are generally made of copper, making the heat sealing work of container mouths more efficient over a long period of time.
It can be carried out and has the effect of being extremely effective.

[Brief explanation of drawings]

FIG. 1 is a partially enlarged sectional view showing a heat sealing device according to a first embodiment of the present invention, and FIG. 2 is an enlarged sectional view of the main part thereof. FIG. 3 is a partially enlarged sectional view showing a heat sealing device according to a second embodiment of the present invention. (1)... Heat sealing device, (2)... Heat pressing member,
(3)... Copper thin plate (metal thin plate), (4)... Upper elastic body, Ri6)... Cylindrical mounting member, (7)... Receiving part, (8)... Inner cylinder shaped mounting member, (9)...receiving part,
(10)...Glass container, (11)...Opening, <I2
)...Lid, (13)...Aluminum foil, (14)-
・Heat sealing material layer, (20) (20a) (20b)--Gap to allow expansion/contraction of thin copper plate, (2+)(22)...Gap for relief of expanded fat part of upper elastic body, (23)--Lower elastic Gap for releasing body fat. Patent applicant: Showa Aluminum Co., Ltd.
Kishimoto Eiyuki Suukei 3rd name ■1゛4, T, '31, r.

Claims (1)

[Claims] A heating pressing member (2), a disc-shaped or annular thin metal plate (3) arranged to be thermally connected to the lower side of the heating pressing member (2), and a portion of the thin metal plate (3) scheduled to be pressed around the container opening. The upper elastic body (4) is housed in the annular recess (16) on the lower surface of the corresponding heating pressing member (2), and the upper elastic body (4) is attached to the peripheral edge of the heating pressing member (2) and the peripheral edge of the thin metal plate (3). A cylindrical mounting member (
6) in a heat sealing device comprising a heating pressing member (2);
) The upper elastic body (4) is housed in the annular recess (16) on the lower surface.
) and an inner circumferential surface of the annular recess (16) opposite thereto, an elastic body escape gap (21) (22) is provided for the container. Heat sealing device for lids.