JPH04124915U - metal lid for cans - Google Patents

Abstract

(57) [Summary] [Purpose] To efficiently perform vacuum deaeration and inert gas blowing during deaeration using the vacuum/gas replacement method. Prevents contents from adhering to the lid during vacuum degassing and inert gas blowing. To ensure the sealing performance of a seaming part after a lid is fixed to a can body. [Structure] A metal lid body (2), which is glued to the back side of the lid body (2), and which is attached to the back side of the peripheral wall (3a) of the recessed part (3) of the lid body (2) and the back side of the flange (4). It consists of a covering molded body (6). The exposed surface of the covering molded body (6) opposite to the surface bonded to the lid body (2) is formed of a synthetic resin that is non-adhesive at room temperature and exhibits adhesive properties when heated. A gas passage (12) is formed in the surface of the covering molded body (6) facing the can body (15) of the portion (6a) that covers the back surface of the peripheral wall (3a) of the concave portion (3).

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention is applicable to tea leaves, nuts, coffee, tobacco, potato chips, etc. This invention relates to metal lids for cans that are applied to dry pack products such as milk powder and milk powder.

0002

[Conventional technology]

Dry tea leaves, nuts, coffee, tobacco, potato chips, powdered milk, etc. Packed products are treated internally to prevent oxidative deterioration of the contents and corrosion of the inner surface of the can. After filling the container, degas it by vacuum/gas replacement method, vacuum degassing method, gas blowing method, etc. After that, the lid is secured by tightening the lid.

0003 Conventionally, this type of metal lid has a recess that fits into the opening of the can body. , a flange is provided continuous to the peripheral wall of the recessed part, and a car is continuous to the tip of the flange. A sealing compound is applied to the back side of the flange, and the After tightening, the sealing compound works to ensure the sealing of the seamed part. The one given was used.

0004 In the case of such metal lids, for example, when degassing using the vacuum/gas replacement method, Vacuum deaeration and inert gas blowing are carried out when the open end of the peripheral wall of the can body is connected to the flange of the lid. Place the lid on the can body so that it is in contact with the back side, and the lid and can A slight gap is formed between the body and the body, and the process is carried out through this gap.

[0005]

[Problem that the idea aims to solve]

However, with traditional metal lids, sealing compound is applied to the back side of the flange. is applied, and the open end of the peripheral wall of the can body is in contact with the sealing compound on the lid. This prevents the lid from floating away from the can body during vacuum degassing and inert gas blowing. The air volume inside the can is lowered to the required level because it is difficult to lift and the efficiency is low. The problem was that it took a long time. Moreover, the amount of air inside the can is There was a problem that it became impossible to lower the level to a level that could be lowered. Also, Sealin Gluing compound is sticky at room temperature, so it should not be used during vacuum degassing or inert gas. When blowing the sealant, the contents such as tea leaves may adhere to the sealing compound and cause the sealing compound to tighten. There was a problem in that the sealing performance after cleaning deteriorated.

[0006] The purpose of this invention is to provide a metal can lid that solves the above problems.

[0007]

[Means to solve the problem]

The metal lid for cans invented by this invention is for cans that is fixed to the open end of the can body by seaming. A metal lid, comprising a recess that fits into the opening of the can body, and a peripheral wall of the recess. A flange is provided continuous to the flange, and a curl is provided continuous to the tip of the flange. A metal lid body and a metal lid that is glued to the back side of the lid body and attached to the back side of the recessed peripheral wall of the lid body. and a cover molded body that covers the back side of the flange. The exposed surface opposite to the surface bonded to the Made of a synthetic resin that exhibits adhesive properties, it covers the back surface of the peripheral wall of the recessed part of the covering molding. A gas passage is formed on the surface of the portion facing toward the can body.

[0008] In the above, the covering molded article may be made entirely of polyethylene resin or is a sheet made of polyolefin thermoplastic resin such as polypropylene resin ( Including film. (same below), both sides of the polyethylene terephthalate resin layer are made of polyethylene. Polyolefin thermoplastic resin layer such as ethylene resin or polypropylene resin Covered laminated sheet, aluminum foil (including aluminum alloy foil; the same applies hereinafter) Both sides are made of polyolefin thermoplastic such as polyethylene resin or polypropylene resin. Aluminum foil composite laminate covered with plastic resin layer, one side of aluminum foil at room temperature It is covered with a hot-melt layer that is non-stick and exhibits adhesive properties when heated; The surface is polyolefin thermoplastic such as polyethylene resin or polypropylene resin. Molded from a sheet material such as an aluminum foil composite laminate covered with a resin layer. is used. When using an aluminum foil composite laminate with a hot melt layer If the hot melt layer covers the back side of the recessed wall and the back side of the flange, the hot melt layer will be exposed. It is made to face.

[0009] The can body can be made of metal, composite materials mainly made of metal, paper, or composite materials mainly made of paper. Materials made of composite materials, plastics, and composite materials mainly made of plastics are used. I can stay.

0010

[Effect]

The metal lid body is bonded to the back side of the lid body, and the back side of the concave peripheral wall of the lid body. and a cover molded body that covers the back side of the flange. The exposed side opposite to the side bonded to the body is non-stick at room temperature and resistant to heat when heated. If it is made of synthetic resin that exhibits adhesive properties, vacuum/gas replacement methods, vacuum degassing methods, etc. Gas blowing during degassing, vacuum/gas replacement method, gas blowing method, etc. Sometimes, the lid easily lifts off the can body due to the pressure difference inside and outside the can body, creating a gap between the two. It is formed. Therefore, deaeration or gas injection can be carried out efficiently through this gap. It can be carried out. Moreover, the portion of the covering molded body that covers the back surface of the peripheral wall of the concave portion is If a gas passage is formed on the side facing the can body, degassing or gas injection will be difficult. This can be done with high layer efficiency.

[0011] In addition, the exposed surface of the covering molded body opposite to the surface bonded to the lid body is kept at room temperature. If it is made of a non-adhesive synthetic resin, it may cause damage when degassing or blowing gas. Contents such as tea leaves are prevented from adhering to the back surface of the flange portion of the lid.

0012 Furthermore, the exposed surface of the covering molded body opposite to the surface bonded to the lid body is processed. If the lid is made of synthetic resin that exhibits adhesive properties when heated, the lid cannot be secured to the can body by tightening. After fixing the seam, heat the seaming part, and this synthetic resin will exhibit adhesive properties. Both side parts are glued together through the adhesive.

[0013]

【Example】

Examples of this invention will be described below with reference to the drawings. In the following explanation, The same parts and parts are denoted by the same reference numerals throughout the drawings, and their explanation will be omitted.

[0014] Example 1 This embodiment is shown in FIGS. 1 and 2. In the same figure, a metal can lid (1) has a recess (3) that is fitted into the opening of the can body, and the peripheral wall of the recess (3) A flange (4) is connected to (3a), and a curl is connected to the tip of the flange (4). (5) and the back side of the lid body (2) with adhesive or the like. The peripheral wall (3a) of the concave portion (3) of the lid body (2) is and a covering molded body (6) that covers the back surface of the bottom wall (3b) and the back surface of the flange (4). It becomes more.

[0015] The lid body (2) may be made of steel, aluminum, etc. with anti-corrosion treatment on the surface. It was formed from.

[0016] The covering molded body (6) has almost the same shape as the lid body (2), and is made of aluminum foil. (7) One side of the hot melt adhesive is non-adhesive at room temperature and exhibits adhesive properties when heated. Aluminum foil composite covered with a polyethylene resin layer (8) and a polyethylene resin layer (9) on the other side. The composite laminate (10) is drawn and formed so that the hot melt layer (8) is on the outside, and the lid body (2) is formed. ) is formed by making the shape almost the same as that of Molding for coating The lid is removed from the part (6a) that covers the back surface of the peripheral wall (3a) of the recessed part (3) of the lid main body (2) in the body (6). The aluminum foil composite laminate (10) extends over the part (6b) covering the back side of the lunge (4). Overlapping parts (11) that partially overlap and protrude outward are spaced apart in the circumferential direction. A few have been formed. The part between adjacent overlapping parts (11) is made into a gas passage (12). ing.

[0017] Figures 3 to 6 show how tea leaves are sealed in cans by applying the vacuum deaeration/gas replacement method, for example. The method for doing this is shown in step-by-step order. In advance, the bottom opening fixes the separately formed bottom cover (16). or of the peripheral wall of the can body (15) closed with an integrally formed bottom wall. A flange (15a) is formed at the upper end. The contents (S) are inside this can body (15). After filling, the flange (15a) of the can body (15) touches the back side of the flange (1a) of the lid (1). Place the lid (1) over the can body (15) so that the can body (15) is closed, and temporarily tighten it (see Figure 3). At this time, the covered The weight of the portion (6a) of the covering molded body (6) that covers the peripheral wall (3a) of the concave portion (3) of the lid body (2) The protruding end of the bent portion (11) is in contact with the inner peripheral surface of the can body (15), and there are multiple A gas passage (12) is present (see Figure 4). In addition, the lid of the covering molded body (6) The protruding end of the overlapping part (11) of the part (6b) covering the flange (4) of the main body (2) is connected to the can body (15). Flange (15a) Touches the tip. The above preliminary seaming is performed during vacuum degassing in the post process and This is done to prevent the lid from shifting when inert gas is injected, and is used to prevent vacuum release. The lid (1) can be lifted up when blowing air or inert gas. It has become.

[0018] Next, the can body (15) with the lid (1) temporarily tightened is placed in the vacuum chamber (17), and the vacuum is applied. Open the valve (19) provided in the exhaust passage (18) of the exhaust system (not shown) and The valve (21) installed in the inert gas supply path (20) of the active gas supply device (not shown) Close the chamber (17) using a vacuum pump (not shown) to reduce the pressure inside the can body (15). Evacuate under vacuum (see Figure 5). At this time, first, the pressure outside the can body (15) is reduced to the inside of the can body (15). As shown in Figure 5, this pressure difference causes the lid (1) to It easily lifts up from the can body (15), and a gap is formed between the two, through which the can can escape. Qi is done efficiently. Moreover, due to the function of the gas passage (12) of the coating molded body (6), , deaeration is performed more efficiently.

[0019] After the pressure is reduced to the specified degree of vacuum, stop the vacuum pump and close the valve (19). At the same time, open the valve (21) to create a vacuum using an inert gas supply device such as nitrogen gas. Inert gas is blown into the chamber (17) to return the inside of the vacuum chamber (17) to normal pressure. At this time, first, the pressure outside the can body (15) becomes lower than the pressure inside the can body (15), so Due to these pressure differences, the lid (1) easily lifts off from the can body (15), creating a gap between the two. (see Figure 6), and inert gas can be efficiently fed through this gap. It will be done. Moreover, the gas passage (12) of the coating molded body (6) allows for the delivery of inert gas. The integration is performed more efficiently.

[0020] Then, the lid (1) is fixed to the can body (15) by the double seaming method. In addition, the above vacuum release Part of the contents (S) is removed from the can body (15) along with the gas when air is removed or inert gas is blown into the can. However, the surface of the covering molded body (6) opposite to the surface adhered to the lid body (2) Hot-melt material whose exposed surface is non-adhesive at room temperature and becomes adhesive when heated. Since it is covered with the layer (8), the contents (S) will adhere to the back side of the flange (1a) of the lid (1). is prevented. Therefore, some of the contents (S) may remain in the seaming part during double seaming. Existence is prevented.

[0021] Finally, heat the seam part so that the hot melt layer (8) exhibits adhesive properties. , thereby sealing.

[0022] In this example, the flange (4) of the lid body (2) in the covering molded body (6) An overlapping portion (11) is also formed in the portion (6b) that covers the gas passage (12). However, the gas passage (12) may not be present in this part.

[0023] Example 2 This embodiment is shown in FIG. In the figure, a molded body (6) for covering the lid (25) is shown. ), the part (6a) covering the back surface of the peripheral wall (3a) of the recessed part (3) of the lid body (2) is A plurality of protrusions (26) extending in the direction are formed at intervals in the circumferential direction. And next door The portion between the contacting protrusions (26) serves as a gas passage (27). In addition, in this example , each protrusion (26) extends from the flange (4) of the lid body (2) in the covering molded body (6). It may be formed so as to extend to the covering portion (6b). Also, instead of the protrusion (26) A plurality of grooves may be formed. In this case, the inside of the groove becomes a gas passage.

[0024] Example 3 This embodiment is shown in FIG. In the figure, a molded body (6) for covering the lid (28) is shown. ) in the recessed part (3) of the lid body (2) in the part (6a) that covers the back surface of the peripheral wall (3a). A plurality of protruding ridges (29) are formed in a staggered arrangement. Then, the adjacent The portion between the strips (29) is a gas passage (30).

[0025] Example 4 This embodiment is shown in FIG. In the figure, a molded body (6) for covering the lid (31) is shown. ) and the part (6a) that covers the back surface of the peripheral wall (3a) of the recessed part (3) of the lid body (2) and the flap. A large number of protrusions (32) are formed on the portion (6b) that covers the back surface of the hinge (4). and, The portion between each protrusion (32) is a gas passage (33). Note that in this example Therefore, the part (6a) of the covering molded body (6) that covers the flange (4) of the lid body (2) is The protrusion (32) may not be formed.

[0026] The method of closing the upper end opening of the can body (15) using the lids of Examples 2 to 4 above is based on the method described above. This is the same as Example 1.

[0027]

[Effect of the idea]

According to the can metal of this invention, as mentioned above, the vacuum/gas replacement method, vacuum deaeration method, etc. Gas blowing during degassing, etc., vacuum/gas replacement method, gas blowing method, etc. When cleaning, a gap easily forms between the can body and the lid, allowing deaeration to occur through this gap. Alternatively, gas can be blown efficiently. Therefore, the amount of air inside the can It can shorten the time required to lower the level to the required level, and It is possible to reliably reduce the amount of air inside the can to the required level. Moreover, the coating Gas formed on the surface facing the can body of the part covering the back surface of the peripheral wall of the concave part in the molded product Through the passage, deaeration or gas blowing can be carried out more efficiently.

[0028] Also, during vacuum degassing and inert gas blowing, contents such as tea leaves may be removed from the lid. This prevents it from sticking to the back of the flange, reducing the sealing performance after seaming. can be prevented.

[0029] Furthermore, after fixing the lid to the can body by seaming, if the seaming part is heated, the coating The synthetic resin that forms the exposed surface of the molded body opposite to the surface bonded to the lid body is in contact with Since it exhibits adhesive properties, both side parts are adhered through this. Therefore, seaming The opening is completely sealed.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view showing a first embodiment of the metal can lid of the invention.

FIG. 2 is an enlarged sectional view taken along line II-II in FIG. 1;

FIG. 3 is a vertical cross-sectional view of the lid temporarily tightened to the can body in the vacuum degassing/gas replacement method.

FIG. 4 is an enlarged sectional view taken along the line IV-IV in FIG. 3;

FIG. 5 is a vertical cross-sectional view of the state of vacuum degassing in the vacuum degassing/gas replacement method.

FIG. 6 is a vertical sectional view showing a state in which an inert gas is blown in.

FIG. 7 is a perspective view showing a second embodiment of the metal can lid of the invention.

FIG. 8 is a perspective view showing a third embodiment of the metal can lid of the invention.

FIG. 9 is a perspective view showing a fourth embodiment of the metal can lid of the invention.

[Explanation of symbols]

1 Metal lid for cans 2 Metal lid body 3 Recessed part 3a Peripheral wall 4 Flange 5 curl 6 Molded object for coating 6a Part covering the back side of the recessed part surrounding wall 8 Hot melt layer (synthetic resin) 12 Gas passage 15 Can body 25 Metal lid for cans 27 Gas passage 28 Metal lid for cans 30 Gas passage 31 Metal lid for cans 33 Gas passage

Claims (1)

[Scope of utility model registration request] Claim 1: A metal lid for a can that is fixed to the open end of a can body by seaming, comprising a recess that is fitted into the opening of the can body, and a flange that is continuous with the peripheral wall of the recess. The metal lid body is provided with a curl extending to the tip of the flange, and the covering molded body is adhered to the back surface of the lid body and covers the back surface of the peripheral wall of the concave portion of the lid body and the back surface of the flange. , the exposed surface of the covering molded body opposite to the surface bonded to the lid body is formed of a synthetic resin that is non-adhesive at room temperature and exhibits adhesive properties when heated, and the back surface of the recess surrounding wall of the covering molded body is A metal lid for cans that has a gas passage formed on the surface facing the can body that covers the can.