JP2003094133A - Can with thread, its manufacturing method, and lidded case using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet metal can with thread which scarcely injures user's fingers or the like when being handled, and is resistant to corrosion caused by its contents. SOLUTION: The can A with thread has a neck 3 having a thread 4 formed by irregularity deformation. The curl 5, the thickness (t) of which is thinner than an original thickness T, is provided at the upper end of the neck 3. A paint film or a coat is formed on the inner surface side of a can body including the neck 3, and the curl 5 is formed outwardly.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a screw can, a manufacturing method thereof, and a lidded container using the screw can.

[0002]

2. Description of the Related Art Conventionally, a screw can 1 as shown in FIG.
01 is used. This is a cylindrical neck 10
A screw portion 104 is provided in order to screw the cap 103 or the like around the periphery of the screw 2. Also, the tip 105 of the neck 102
Is made flat by shaving so as to be in close contact with the inner surface of the cap 103 or the gasket 106. Such a screw-equipped can 101 is formed by forming a thin metal plate such as aluminum into a cylindrical shape with a bottom, forming a shoulder 107 and a neck 102 by mouth-drawing, and forming the tip end thereof with the root diameter of the screw to be formed. It is manufactured by drawing into a cylindrical shape having a diameter of about a certain degree, and then the remaining portion is deformed unevenly by roll forming or the like to form the screw portion 104.
The manufacturing method, especially the method of molding the screw portion, is described in, for example, Japanese Patent Application Laid-Open No. 5-229545.

In such a screw can 101, in order to protect the surface of the metal plate from corrosion due to the contents to be filled or to protect the contents from metal, spray coating on the inner surface of the can body after the can is made. , A synthetic resin coating film may be provided by powder coating. Further, a synthetic resin film may be heat-welded to a thin metal plate and the can body may be molded with the film surface facing inward.

[0004]

[Problems to be Solved by the Invention] The conventional screw can 1
In No. 01, since the tip 105 of the neck is flattened by the shaving process, there is a corner (edge), and therefore the user's finger or the like may feel pain. Further, even when a coating film or coating for preventing corrosion is provided, the tip end 105 of the neck portion has no coating film or coating and the metal is exposed. Therefore, the metal in that portion may be corroded by the contents. The first technical object of the present invention is to provide a can with a screw that is easy on the hands and does not hurt when touched by a user's finger or the like. A second technical object of the present invention is to provide a can with a screw in which the tip of the neck portion is not easily corroded by the contents. Further, it is a technical object of the present invention to provide a method for producing such a screw can and a container with a lid utilizing the unique properties of the screw can.

[0005]

The threaded can of the present invention is a metal thin plate can body having a neck portion having a threaded portion due to uneven deformation. It is characterized in that a curl portion thinner than the wall thickness is provided. In such a screw can, it is preferable that a coating film or a coating is formed on the inner surface side of the can body including the neck portion, and the curl portion is wound outward.

According to the method of manufacturing a can with a screw of the present invention, a can body made of a thin metal plate having a cylindrical neck portion is formed, and a screw portion is formed around the neck portion by uneven deformation, leaving the vicinity of the upper end thereof, Next, the vicinity of the upper end is cut to be thin, and the thinned portion is curled. The can body may be formed from a thin metal plate, and
It may be formed from slag by impact molding. In this manufacturing method, it is preferable that a coating film or a coating is formed on the inner surface side of the can body and the thinned portion is curled outward at any stage before the curling.

The container with a lid of the present invention comprises the above-mentioned screw can,
It has a lid body that is screwed into the threaded portion of the neck of the screwed can,
It is characterized in that a contact surface is provided at a portion corresponding to the curl portion on the upper inner surface of the lid body. In such a container with a lid, the lid or the neck may be provided with a means for taking out the contents, and the taking out means may be provided with a flange portion sandwiched between the curl portion and the contact surface. A second aspect of the container with a lid of the present invention has the above-mentioned screwed can, a lid body screwed into a threaded portion of the neck portion thereof, and a means for taking out contents attached to the neck portion, The take-out means has a fitting portion that fits with the curl portion.

[0008]

In the screwed can of the present invention, since the curled portion is provided at the upper end of the neck portion, the corner portion of the edge of the metal thin plate is caught and is not exposed to the outside. Therefore, even if the user's finger or the like hits the upper end of the neck, no pain is felt. Further, since the thickness of the curled portion is thin, deformation such as buckling is unlikely to occur in the screw portion even when the curled processing is performed after the screw processing. That is, since the screw portion has a spiral shape, the load is not evenly applied on the entire circumference, and therefore the screw portion is likely to buckle. However, in the threaded can of the present invention, since the curl portion has a thin wall thickness, it is possible to reduce the axial load during curl molding. Therefore, curling after screwing is easy.

Further, since the curl portion is thin, the winding diameter of the curl portion can be reduced. Therefore, the curl width can be reduced, and both functions of ensuring the area of the opening and screwing the cap can be achieved. If the neck has a smaller diameter on the upper part of the body,
The neck tends to be thicker than the trunk. Therefore, the advantage of reducing the wall thickness of the curl portion is further utilized.

In a screwed can in which a coating film or coating is provided on the inner surface of the can body including the neck portion, the metal at the tip of the curl portion is not exposed, and the portion is not easily corroded by the contents. When the curl portion is wound outward, the effect of preventing corrosion is further enhanced. It is also easy to mold.

In the method of manufacturing a screw can according to the present invention,
It is easy to bend because the vicinity of the upper end of the neck is thinned by cutting and then curled. Therefore, the buckling of the screw part is difficult during curling. Also, after manufacturing the cylindrical can,
When forming a neck with a smaller diameter than the body by drawing,
The thickness of the neck tends to be thick. Therefore, the buckling prevention effect by cutting the neck portion to a thin wall is further increased.
When a coating film or coating is provided before curling and the curling portion is wound outward, there is an anticorrosion effect on the tip and surface of the curling portion.

In the container with lid of the present invention, since the upper surface of the curl portion has no corners, there is little risk of damaging the contact surface or the gasket. Therefore, the lid can be securely fastened to the neck. When the flange portion of the takeout means provided on the lid body or the neck portion is sandwiched between the contact surface of the lid body and the curl portion, the takeout means can be firmly held. Further, when the take-out means is provided with a fitting portion for fitting with the curl portion, there is an advantage that the take-out means can be firmly attached to the neck portion.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a screw can, a method for manufacturing the same, and a container with a lid according to the present invention will be described below with reference to the drawings. 1 (a) is a cross-sectional view of an essential part showing an embodiment of a screw can of the present invention, FIG. 1 (b) is a process drawing of an essential part showing an embodiment of a method of manufacturing the screw can, and FIG. FIG. 3 (a) and FIG. 3 (b) are process diagrams showing the previous process of the manufacturing method of FIG. 1 (b).
Is a schematic cross-sectional view showing an embodiment of the threaded can of the present invention, FIG. 4 is a main-part cross-sectional view showing another embodiment of the threaded can of the present invention, and FIGS. It is sectional drawing which shows the embodiment of a container.

As can be seen from FIG. 3 (a) showing the whole of the screwed can A shown in FIG. 1, a barrel-shaped body 1 having a bottom and a shoulder 2 continuous with the upper portion of the body 1 are provided. , A cylindrical neck portion 3 which is continuous above the shoulder portion 2. The body 1 is usually cylindrical, but may be rectangular. The neck 3 is shown in FIG.
As shown in (a), it comprises a large diameter portion 3a and a small diameter portion 3b having a diameter somewhat smaller than that of the large diameter portion. The large diameter portion 3a and the small diameter portion 3b are smoothly continuous in a conical portion.

A screw portion 4 is formed on the large diameter portion 3a. The screw portion 4 reaches the upper end of the large diameter portion 3a. The small-diameter portion 3b is formed with a curl portion 5, which is a feature of the present invention. Body 1, shoulder 2, neck 3 and its large diameter portion 3a
The threaded portion 4 formed in 1 is substantially the same as the conventionally known threaded can. This screwed can A is manufactured from a blank material obtained by punching a metal thin plate such as aluminum or steel into a circle in the following procedure.

The thickness of the thin metal plate used is usually 0.2 to
It is about 1.0 mm, and a coating film or coating is provided.
The coating film may be formed by a known method such as spray coating a synthetic resin such as an epoxyphenol resin, a polyamideimide resin, an epoxyamino resin, a vinyl resin, or powder coating. The coating film is provided in the state of a thin metal plate, but it may be provided after being formed into a can body. In the case of coating, it can be provided by a known method such as thermally adhering a thermoplastic film such as polyester or polyethylene terephthalate to the metal thin plate.

The circular blank material is formed into a bottomed cylindrical shape shown in the first step S1 of FIG. 2 by a known deep drawing process or the like. The outer diameter D of the can body is, for example, about 30 to 100 mm. Note that the ironing process may be performed after the deep drawing process. Further, in the case of aluminum or the like, it can be formed into a bottomed tubular shape by impact molding or the like from slag.

The upper end of the bottomed cylindrical can body is necked (drawn) to form the shoulder portion 2 and the neck portion 3 as shown in the second step S2. Further, by necking again, as shown in the third step S3, the diameter of the upper portion of the neck portion 3 is further reduced and the tip portion 3c is reduced.
Can also be

Next, as in the fourth step S4 and the fifth step S5, roll forming is performed by a known roll forming machine to form the threaded portion 4 having a corrugated cross section. The outer diameter of the screw thread (d1 in FIG. 1 (a)) is, for example, 20 to
The root diameter (d2) is about 45 mm and about 19 to 44 mm. In the case of a conventional screw can, after this molding, a shaving process is performed with a bite or the like in order to flatten the tip of the neck 3.

However, in this embodiment, as shown in FIG. 1 (b), the mouth end portion 3c is further drawn so that the small-diameter portion 3 is formed.
b is formed (sixth step S6). The remaining part is the large diameter part 3
a. The wall thickness T of the small diameter portion 3b is, for example, 0.2 to 1.
It is about mm. Next, the outer circumference of the small diameter portion 3b is cut to reduce the wall thickness (seventh step S7). The wall thickness t in the thinned state varies depending on the curl diameter and the curl width W, but is usually 20 to 70% (0.14 to 0.7 mm) of the original wall thickness T.
It is about 50% to about 60% of the original wall thickness T. This is because if the thickness is too thick, buckling is likely to occur in the screw portion 4 during curl molding, and if it is too thin, buckling or cracking may occur in the small diameter portion 3b. When cutting the outer peripheral surface, the tip may be shaving flatly.

Next, as shown in the eighth step S8, the curl die 10 is used to curl the thin small-diameter portion 3b outward. The pressing direction is the axial direction of the can body. By this curl molding, the curl portion 5 is formed as shown in FIG. The outer diameter d3 of the curl portion 5 is smaller than the mountain diameter (inner diameter) of the female screw of the cap or the like in order to screw the cap or the like onto the screw portion 4, and is usually smaller than the root diameter d2 of the screw portion 4. Somewhat small size. The curl width W is
It is preferably as small as possible in the range where it can be molded, but if the winding diameter is too small, the inner coating film will be damaged.
It is preferably about mm, particularly about 1.5 to 2.5 mm.

Screwed can A manufactured as described above
Has a curl portion 5 at the upper end of the neck portion 3,
It is hard to damage the user's fingers. Furthermore, since the tip of the neck portion 3 is not exposed, it can be protected from corrosion by the contents. Further, since the curl width W is small, it is possible to secure a sufficient opening area without impairing the function of the screw portion 4 such as tightening a screw cap. Further, when the cap is screwed, the inner bottom surface of the cap comes into contact with the curl portion 5, but the curl portion 5 is not deformed even if it is strongly tightened. Further, as will be described later, the lid can be attached by utilizing the peculiar shape of the curl portion.

In the screwed can A shown in FIGS. 3 (a) and 1, a thin neck portion 3 is provided on the body portion 1 via a shoulder portion 2. However, when the body portion has a cylindrical shape, the case shown in FIG. As in the case of the screwed can B shown in b), the neck portion 3 can be used as it is near the upper end opening of the body portion 1. In this case, it is preferable that the diameter of the neck 3 be somewhat smaller than that of the body 1 in order to make the outer surfaces of the cap and the body 1 flush with each other (see FIG. 7). The position and width of the curl portion 5 and the molding method are substantially the same as in the case of the screw can A of FIG.

The screw can C shown in FIG. 4 is substantially the same as the screw can A of FIG. 1 except that the curl portion 5 is wound inward. In this case as well, the tip 5a of the curl portion 5, that is, the tip 5a of the small-diameter portion 3b before being curled is in close contact with the root of the curl portion 5 and is not exposed. Therefore, if a coating film or coating is provided on the outer surface which becomes the inner side by curling, the content does not directly touch the exposed portion of the metal, so that both the metal and the content are protected. If the outer surface of the can body has no coating or coating because the curl portion 5 is internally wound, a coating film is formed on the curl portion 5 after curling.

In the screwed can C of FIG. 4, in order to increase the inner diameter of the curl portion 5, the portion of the small-diameter portion 3b to be curled is expanded to some extent, and then the outer surface side is cut to a thin wall, It curls in the direction. However, the small diameter part 3b
It is also possible to curl by extending straight up without expanding the diameter. Further, in the above-mentioned embodiment, the inner coating film or coating for protection is provided, but it is not necessary to provide it depending on the contents. Even in that case, the curl portion has an effect of protecting the user's finger or the like. If it is not necessary to provide an inner coating film or coating, the inner surface side of the small diameter portion 3b may be cut. In addition, the curl can be freely turned inward or outward. Even when the coating film is provided after cutting, the inner surface side of the small diameter portion can be cut.

Next, an embodiment of the container with a lid of the present invention will be described with reference to FIGS. FIG. 5 shows a lidded container D1 including the screwed can A shown in FIGS. 1 to 3 and a cap 15 screwed to the neck portion 3 thereof. The cap 15 has a disk-shaped top surface 15a and a cylindrical side surface 15b. The cap 15 is formed by drawing a thin metal plate, and has a side surface 15b.
This is a conventionally known one in which a female screw portion 16 is molded. However, a cap such as a synthetic resin molded product may be adopted. An annular or disc-shaped gasket 17 is fitted or fixed to the lower surface (upper bottom surface) of the top surface 15a. In this case, the outer peripheral portion of the inner surface of the cap 15 can be considered as the contact surface of claim 5. If the gasket 17 is a part of the cap, it can be considered that the lower surface of the gasket 17 is the contact surface.

Since the curved surface of the curl portion 5 contacts the gasket 17 in the above-described container D1 with a lid, even if the cap 15 is strongly tightened or repeatedly opened and closed, the gasket 17 is closed.
Is hard to damage. Therefore, the sealing action can be maintained for a long time. Further, since the screw can A with the inner coating film provided with the outward curl portion is adopted, the same effect as the case of FIGS.

In the lidded container D2 shown in FIG. 6, a lid 18 with a pump is attached to the above-described screwed can A. The lid 18 is a synthetic resin molded product having a cylindrical shape with a bottom and a guide portion 20 for guiding the push button 19 on the top surface thereof. On the inner surface of the peripheral wall of the lid body 18, a female screw 18a that is screwed with the screw portion 5 of the screw can A is formed. The pump 21 is attached to a housing 22 housed inside a can A with a screw, a suction pipe 23 vertically movable in the housing 22, a push button 19 attached to the upper end thereof, and a lower end of the housing 22. It is a known one having a dip tube 25. The suction pipe 23 penetrates the top surface of the lid 18 and extends upward, and the push button 19 makes sliding contact with the inner surface of the guide 20. The housing 22 has a flange portion that fits with the inner bottom surface of the lid body 18. The flange portion 26 and the gasket 27 provided on the lower surface side thereof are sandwiched between the inner bottom surface of the lid body 18 and the upper surface of the curl portion 5.

In this lidded container D2, when the push button 19 of the pump 21 is pushed, the contents in the housing 22 are ejected from the ejection nozzle 29 of the push button 19 through the suction pipe 23. The curl portion 5 is similar to the case of the lidded container D1 in FIG. 5 in that it is difficult to damage a finger or the like, the tip of the neck portion 3 is not easily corroded, the gasket 27 is not easily damaged, and the seal is reliable.

The container with lid D3 shown in FIG. 7 is a can with screw B2.
And a roll coater 30 attached to the upper end of the neck portion 3, and a cap 31 screwed around the neck portion 3. The screwed can B2 has a bottomed cylindrical body 1, a conical surface-shaped shoulder 2 continuous with the upper end thereof, and a neck 3 continuous with the upper end thereof. The width of the shoulder portion 2 of this screwed can B2 is narrow, and therefore the screwed can B2 has a form similar to that of the screwed can B of FIG. 3 (b). Further, the neck portion 3 has a large diameter portion 3a having a screw portion 4.
And a small-diameter portion 3b that is continuous therewith, and a curl portion 5 that curls outward is formed on the small-diameter portion 3b.

The roll coater 30 has a spherical recess 32.
And a ball 34 rotatably held in the recess 32. An opening 35 that connects the recess 32 and the inside of the can is formed on the lower surface of the holder 33, and the ball 34 closes the opening 35. An annular projection 36 is provided at the upper end of the recess 32 of the holder 33 to prevent the ball from coming out. Further, an annular groove 37 is formed in the lower portion of the peripheral wall of the holder 33 so as to be closely fitted with the curl portion 5 of the screwed can B2. This annular groove 3
Reference numeral 7 is the fitting portion of claim 7. Instead of the annular groove, it is possible to provide another type of fitting portion such as a fitting step portion that fits with the upper surface and outer surface of the curl portion, or with the upper surface and inner surface of the curl portion. The bottom portion 38 of the holder 33 has a cylindrical shape that closely engages with the inner surface of the curl portion 5, that is, the inner surface of the small diameter portion 3b.

The cap 31 is a roll coater 30.
And a female screw portion 39 that is screwed into the screw portion 4 is formed on the inner surface of the lower end. The roll coater 30 is a means for taking out the contents of claim 7. This container D3 with a lid removes the cap 31 and turns it upside down to make balls 34
When is contacted with the coating surface of the other party and is rolled, the contents coming out of the opening 35 adhere to the surface of the ball 34 and can be further coated on the coating surface of the other party. Furthermore, by fitting the curl portion 5 with a large hoop stress and the annular groove 37,
The holder 33 can be firmly held in the screwed can B2. Further, the surface of the ball 34 can be protected by securely screwing the cap 31 to the neck 3.

The lidded container D4 shown in FIG. 8 is substantially the same as the lidded container D2 shown in FIG. 6 except that an aerosol valve 40 is provided instead of the pump. That is, the upper lid 42 is formed with the female screw portion 42 a that is screwed into the screw portion 4, and the housing 41 of the aerosol valve 40 is
A flange portion 43 that is sandwiched between the inner bottom surface of the upper lid 42 and the curl portion 5 is provided. Gaskets 44 and 45 are interposed between the flange portion 43 and the curl portion 5, and between the flange portion 43 and the inner bottom surface of the upper lid 42, respectively. At the center of the top surface of the upper lid 42, the housing 4
1. A hole 47 through which a stem 46 is provided which is vertically movable in 1
Are formed. The upper lid 42 is made of a thin metal plate, but may be a synthetic resin molded product. A push button to be attached to the upper end of the stem 46 is omitted.

The lidded container D4 can be used as an aerosol device by filling the inside with the contents consisting of a stock solution and a propellant. However, the upper lid 4
Since 2 is a screw tightening, it is preferable to make the internal pressure relatively low. In this lidded container D4, the aerosol valve 40 mainly made of synthetic resin, the metallic screwed container A and the upper lid 42 can be easily separated and discarded.

In this lidded container D4, when the stem 46 is pushed, the aerosol valve 40 is opened, and the contents can be ejected in the form of mist, liquid or foam through the stem 46 and the push button. Further, the operation and effect based on the screw can A and the operation and effect of sealing the upper lid 42 and the screw can A are substantially the same as those of the case D2 with a lid shown in FIG.

[Brief description of drawings]

FIG. 1 (a) is a cross-sectional view of an essential part showing an embodiment of a screw can of the present invention, and FIG. 1 (b) is a process drawing of an essential part showing an embodiment of a manufacturing method thereof. .

FIG. 2 is a process drawing showing a previous process of the manufacturing method of FIG.

3 (a) and 3 (b) are schematic cross-sectional views showing an embodiment of a threaded can of the present invention.

FIG. 4 is a sectional view of an essential part showing another embodiment of the screw can of the present invention.

FIG. 5 is a partial cross-sectional side view showing an embodiment of the container with a lid of the present invention.

FIG. 6 is a partial cross-sectional side view showing another embodiment of the lidded container of the present invention.

FIG. 7 is a partial sectional side view showing another embodiment of the lidded container of the present invention.

FIG. 8 is a cross-sectional view of essential parts showing another embodiment of the container with a lid of the present invention.

FIG. 9 is a cross-sectional view of essential parts showing an example of a conventional screw can.

[Explanation of symbols]

A screw can 1 torso 2 shoulder 3 neck 3a Large diameter part 3b small diameter part 3c Mouth 4 screw part 5 Curl section 5a tip W curl width D1 container with lid 15 caps 16 Female thread 17 Gasket D2 container with lid 18 Lid 21 pumps 26 Flange 27 Gasket D3 container with lid B2 screw can 30 roll coater 31 cap 33 holder 34 balls 37 annular groove 39 Female thread D4 container with lid 40 aerosol valve 42 Top lid 42a female screw part 43 Flange 44 45 Gasket

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification symbol FI theme code (reference) B65D 1/12 B65D 41/04 Z 41/04 1/00 C F term (reference) 3E033 BA08 BA09 CA14 CA20 DA03 DB01 EA10 FA01 GA02 3E084 AA02 AA04 AA12 AA22 AA23 AB01 BA01 CA01 CC01 CC03 DA01 DB12 DB18 DC01 DC03 EB02 FA09 FB01 GA01 GB01 HA02 HB03 HD01 LC06 LD22 LG04

Claims (8)

[Claims] 1. A bottomed cylindrical body, a shoulder continuous with an upper portion of the body, and a cylindrical neck continuous with a screw portion due to uneven deformation, which is continuous above the shoulder. However, the shoulder part and the neck part have a can body made of a thin metal plate integrally formed by necking, and a coating film or a coating is formed on the inner surface side of the can body including the neck part, and the vicinity of the upper end of the neck part. A can with a screw, characterized in that the outer surface of is formed by cutting to be thinner than the threaded portion, and a curl portion curled outward is formed. 2. A large-diameter portion in which a neck portion having a threaded portion due to the uneven deformation is continuous with a shoulder portion, and a small-diameter portion smoothly connected to the upper portion of the large-diameter portion via a large-diameter portion and a conical portion. The outer surface near the upper end of the small diameter portion is formed to be thinner than the screw portion by cutting, and the screw portion is provided above the large diameter portion so as to reach the upper end of the large diameter portion. The screwed can described in 1. 3. The curl width of the curl portion is 1.0 to 3.
The screw can according to claim 1, wherein the can has a curl portion having an outer diameter smaller than a root diameter of the screw portion. 4. The screwed can according to claim 1, wherein the outer surface near the upper end of the neck has a thickness of 20 to 70% of the original thickness. 5. A metal thin plate can body having a cylindrical neck portion is formed, a screw portion is formed around the neck portion by uneven deformation, leaving a portion near the upper end thereof, and then the portion near the upper end is cut. A method for manufacturing a can with a screw, which comprises thinning and curling the thinned portion. 6. The manufacturing method according to claim 5, wherein the can body is molded from a thin metal plate. 7. The manufacturing method according to claim 5, wherein the can body is molded from slag by impact molding. 8. The coating or coating is formed on the inner surface side of the can body at any stage before the curling, and the thinned portion is curled outward. Item 5. The manufacturing method according to Item 5.