JP3032450B2 - Three-jaw chuck - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the construction of a chuck portion of a thermoplastic resin string-like chuck or a bag with a plastic film chuck formed mainly by a T-die method or an inflation method. In particular, the present invention relates to an improvement in a claw portion of a chuck which is improved so that anyone can easily open and close a lock portion of the chuck.

[0002]

2. Description of the Related Art A generally used male / female double-claw type chuck (used for a string-shaped chuck or a bag with a chuck) usually has a sectional shape as shown in FIG. It is manufactured by molding a thermoplastic resin as a raw material by a T-die method or an inflation method. Plastic chucks (or bags with chucks) are widely available on the market because they are lightweight, inexpensive, and can be manufactured with high productivity. They have a wide variety of uses, and include small items such as food, medicine, electronic components, stationery, and catalogs. , And is widely used as a structure of an opening that can open and close a storage bag for documents such as books. Such a resealable plastic container (bag)
In recent years, it has been used as a so-called "freezer bag" for refrigerated storage or frozen storage as a household food storage bag, and also as a so-called "freezer bag" that can be microwave-thawed as a bag. Products with a wider width as shown in FIG. 3 have also become commercially available.

[0003] Conventionally used male and female double-jaw chucks have a narrow base of the chuck jaws, and not only have problems in terms of stability and molding stability but also open and close. Operation, especially the operation of closing the chuck, was unstable. That is, when the chuck is once opened, the contents are filled, and the chuck is to be closed, even if the male claw is fitted to the female claw, it is difficult to enter the claw easily, and derailment often occurs. This means that the width of the base of the male nail is narrower than its height, and when the female nail is pressed to fit the male nail, the male nail is inclined and derails easily depending on the degree of operation force applied. Is the cause. This tendency is increasingly strong when the housewife tries to close the chuck with wet hands, etc. in the kitchen, etc., and avoids shortening the life of the chuck by repeatedly derailing, which also damages the chuck claw. Will not be able to do it.

[0004] In recent years, "bags with wide-width zippers" widely used in household food preservation bags have been introduced to the market after improving such disadvantages. The chuck of the bag with the wide chuck has an improved base width of the male claw, so that the operation of opening and closing the chuck is facilitated. The enlarged cross-sectional view is as shown in FIG. The width of the base of the general double-jawed chuck was narrow and unstable, causing derailment.In the case of the wide-width chuck, ribs were provided on both sides of the base of the male claw to increase the apparent width of the base. And has a function to serve as a guide for inserting the female claw when the chuck is fitted. However, this wide chuck has a defect that the width of the chuck portion is unusually large and is about 5 mm, and the chuck portion is remarkably large and conspicuous as a general household food storage bag in terms of the overall balance, resulting in poor fashionability.

[0005]

DISCLOSURE OF THE INVENTION The present invention has an excellent sealing function, the opening / closing operation of the chuck is reliable and easy, and furthermore, the chuck is not derailed which causes damage to the chuck. The aim is to develop a slimer and more fashionable plastic chuck.

[0006]

According to the present invention, there is provided: Three claws extend from the base of the base, and the cross section of the center claw is any shape with a low height, the tip bends inward on both sides to form a hook, and engages with the male claw to lock the lock. It consists of two claws to be formed, and the ratio (height / height) of the height including the thickness of the bottom base of the two claws on both sides and the width of the bottom base of the claw portion
B. the width of the base) in the range of 0.2 to 0.8, and the width of the bottom base of the female nail of the chuck is 4.5 mm or less; Two claws extend from the other bottom base, and the ratio (height / base width) of the height including the thickness of the bottom base of the two claws to the width of the bottom base of the claw portion is 0.5 to 1.0, the tip of which is bent outward to form a male claw that forms a lock portion for engagement with the female claw, and the inner rise of the female claw and the male claw is 65-65 from the base . A string chuck having a chuck that extends inclining inward at an angle of 85 ° . In a container provided with a male and female plastic chuck at the opening, Three claws extend from the bottom base on one side of the container opening, and the cross-section of the center claw has an arbitrary shape with a low height, and the tip bends inward on both sides to form a hook, The two claws are engaged to form a lock portion, and the ratio of the height including the thickness of the bottom base of the two claws on both sides to the width of the bottom base of the claw portion (height / width of the base) is 0. B. a plastic chuck female claw having a width of 4.5 mm or less and a bottom base of the female claw of the chuck being 4.5 mm or less; Two claws extend from the bottom base on the opposite side of the container opening, and the ratio of the height including the thickness of the bottom base of the two claws to the width of the bottom base of the claw portion (height / width of the base). Is 0.5 ~
1.0, wherein the tip comprises a male claw that curves outward to form a lock for engagement with the female claw;
And the rise of the inside of the female nail and the male nail is 65-
The above object has been achieved by developing a plastic chuck-equipped container extending inward at an angle of 85 ° .

The container with a string-shaped chuck and a plastic chuck according to the present invention is made of a thermoplastic resin such as high-density polyethylene, low-density polyethylene, polypropylene, polyethylene terephthalate, polyamide, or polyvinyl chloride, similarly to a conventional plastic chuck. , T-die molding, inflation or other extrusion methods. The present inventors have studied the shape and dimensional ratio of a chuck having high sealing performance, easy opening and closing operations of the chuck, and excellent fashionability, and have developed the plastic chuck of the present invention.

Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a view showing an example of the plastic chuck of the present invention. The female nail is constituted by three nails, namely, a central nail 5 and both nails (hereinafter, also simply referred to as female nails) 3, 4 standing on the film 1. The central nail 5 may have an arbitrary shape with a low cross-sectional shape, and stands at the center of the female nail, and increases the rigidity of the female nail when fitted to the male nail.
Helps to make male nail insertion easier. In FIG. 1, the center claw 5 has a triangular cross section, but may have any shape other than the triangular shape, such as a quadrangular shape, a semicircular shape, or a two-line shape.

In the chuck according to the present invention, in order to ensure easy opening and closing of the chuck, particularly easy closing of the chuck, and to prevent breakage of the chuck, the female claws 6 and 7 are required.
(“B” indicates b ₁ and b ₂ in FIG. 1).
The height includes the thickness of the base. ) And the width (b / a) of the width “a” of the bottom base of the nail portion is in the range of 0.2 to 0.8, and the two nails 8 and 9 of the male nail (hereinafter also simply referred to as male nail) )) (“D” in FIG. 1 is d ₁ ,
It refers to d _2. The height includes the thickness of the base. )
The ratio (d / c) of the width "c" of the base of the base to the claw portion is 0.5
It is necessary to be in the range of ~ 1.0. b / a or d /
When the value of c is out of this range, for example, if the value of b / a is less than 0.2 and the value of d / c is less than 0.5, the width of the bottom base is wide, and the bag with the wide chuck is used. There is no change, the appearance balance when used for bags and the like is lost, and fashionability is lacking. On the other hand, when the value of b / a exceeds 0.8 or the value of d / c is 1.
When the value is a large value exceeding 0, the chuck becomes narrow and unstable, and tends to cause derailment. For use as a general household food storage bag, the absolute value of the width “a” of the base at the bottom can be sufficiently used if the width is 4.5 mm or less. In the case of the male nail, the width c of the bottom base is smaller than the width a of the base of the female nail, so that the value of d / c is slightly higher, but there is no problem in formability, rigidity, strength, and the like.

Further, in the chuck having such a height / base width relationship, the rising inside the female claws 3 and 4 extends inwardly at an angle of 65 to 85 ° from the base, and extends. The tip portions 6 and 7 are each bent inwardly in a hook shape, and the hook-shaped bends are engaged with the male claws to form a lock portion, so that a good fitting property is obtained, and the chuck is hardly derailed. . In this case, the bend of the tip of the female claw may have the same shape as the tip 6 and the tip 7 as long as the engagement with the male claw is good, but the female claw that comes to the outside of the container when used for a container, for example, a female The nail 3 has a gentle bend at the tip 6 to make it easy to open from the outside, while the tip 7 of the female nail 4 has a tip so that the chuck does not open from the inside of the bag due to the internal pressure after filling the contents. For example, a measure such as strengthening the bending may be adopted.
As for the male nail, two nails 8 and 9 stand on the film 2, and the inside of them also rises from the base by 65 to 8
It extends inclining inwardly at an angle of 5 ° , with its tips 10 and 11 engaging the tips 6 and 7 of the female nail to form a lock.

[0011]

In order to easily open and close the plastic chuck, it is necessary that the chuck has a wide base. However, if the base width is too wide, the appearance of the bag will be out of balance when formed into a bag, and the chuck will be too large and conspicuous. In order to facilitate opening and closing operations using a generally used double-claw type chuck, the base width (a, c) of the chuck must be increased, but from the viewpoint of the rigidity and strength of the chuck. In order to widen the base widths a and c, it is necessary to increase the thickness of the base film and the size of the claws. When increasing the thickness of the base of the bottom of the chuck and the thickness of the claws,
It is difficult to fill the molten resin into every corner of the complex mold shape in a well-balanced manner due to the flow characteristics of the resin on molding, and it is easy to cause sink marks and uneven thickness, especially for female nails with a large base base width a. The product tends to be unstable in rigidity and strength of the product chuck. In the present invention, since the base width of the female nail is widened, the height of the nail is held low, and b / a is reduced, the problem of instability in terms of molding and strength has arisen.

In the present invention, this drawback is achieved by providing the female nail with a three-claw system and providing the middle nail 5 between the female nails 6 and 7 while keeping the b / a ratio of the female nail small. Solved this problem. The center claw 5 has a low claw height, a wide base width, and has a function as a reinforcing rib of a female claw with a small b / a, and has a sink mark and a thickness caused by shaping instability during molding. It has the effect of eliminating unevenness and giving rigidity and strength to the female nail of the product. Finally, at the time of the chuck opening / closing operation, it plays an important role of also serving as a guide. Among the opening and closing operations of the chuck of the present invention, the opening operation is slightly opened first with the thumb and then gradually propagates through the opening over the entire width. However, the closing force of the chuck is stable, and the opening force is stable. Is small but sticky and opens. Also, when closing the chuck, as in the case of the conventional double-claw type chuck, it is pressed from the outside of the base on both bottoms of the female claw and the male claw and then slid, but it is easily fitted and closed without derailing However, as an incidental feature, at the end of the closing operation, there is a characteristic that a snapping sound and a bursting sound of air can be made to confirm the end of the closing of the chuck.

[0013]

Example: Melt flow rate (JIS K-721)
0, measured in Table 1, condition 4) using a high-pressure low-density polyethylene of 3.0 g / 10 min and having the shape shown in FIG.
The base width “a” is 3.3 mm, and the angle “α” of the female nail 3 on the opening side is “α”.
₁ ”is 80 °, the height“ b ₁ ”and the base width“ a ”
Ratio (b ₁ / a) is 0.45, the angle “α ₂ ” of the female nail 4 on the contents side is 80 °, and the ratio (b ₂ / a) of the height “b ₂ ” to the base width of the base is ) Is 0.41, the center nail is a female nail having a height of 0.5 mm, and the base width c at the bottom is 1.75 m.
m, the angle “β ₁ ” of the male claw 8 on the opening side is 85 °, and the ratio (d ₁ / c) between the height “d ₁ ” and the base “c” is 0.8.
7. The angle “β ₂ ” of the male nail 9 on the contents side is 75 °,
The ratio (d ₂ / c) between the height “d ₂ ” and the bottom base width is 0.84
Was formed from a male claw. After closing this chuck with a length of 5 cm, use a tensile tester to
Grasp the film that follows the female base and set both at 180 °
In a direction perpendicular to the chuck in the direction of, at a pulling speed of 300 mm / min, and the bonding force when the chuck was released was measured.

The opening strength of the chuck is 2.3 k on the opening side.
g / 5 cm width and 4.0 kg / 5 cm width on the contents side. This chuck was used for a household freezer bag (width: 200 mm, length: 210 mm) having a film thickness of 70 μm. In addition to refrigerated storage and frozen storage, it is also possible to thaw the microwave in the bag, and the contents are taken in and out each time it is used, but the opening and closing operation of the chuck is easy and reliable. Could be used without derailment. The chuck was not very noticeable in appearance, and the monitor test by the housewife was also popular. Regarding the opening operation of the chuck, first open it slightly with your thumb and gradually propagate it to the entire width, but in that case, the force is small, but it is necessary,
It was confirmed that the opening was sticky and opened. At the time of closing the chuck, a "snap" sound was heard at the end of the closing operation, and it was confirmed that the closing was completed.

Comparative Example Using a low-density polyethylene resin of the same raw material as in the example, a commonly used double-claw type chuck as shown in FIG. 2 was molded. The width of the bottom base of the female nail is 1.0 mm, and the height / width of the base (b / a) is 1.6.
5, the width of the base at the bottom of the male nail was 0.4 mm, and the width of the height / base (d / c) was 3.6. As in the example,
When the opening force was measured with the chuck closed, the opening force was 2.4 kg / 5 cm width, and no clear difference was recognized from the chuck of the present invention. However, when the contents were put in and taken out of the chuck as a bag of the same size as in the example, derailment occurred during the closing operation of the chuck in the third opening / closing operation due to the wetness, and it was necessary to start over three times.

[0016]

The plastic chuck of the present invention is a three-jaw chuck, has a high sealing function, and has a problem such as derailing of the chuck which has been a major cause of damage to the chuck in opening and closing operations, particularly in closing operations of the chuck. Can be greatly reduced. Also, despite the small height / base width, the moldability is excellent, and troubles in molding such as sink marks and uneven thickness are eliminated and the productivity is excellent. The shape of the chuck may be slim compared to the wide-width chuck, and the bag attached with the chuck is also excellent in fashionability, and the results of monitoring by a user such as a housewife at home have a good reputation.

[Brief description of the drawings]

FIG. 1 is a sectional view of a plastic chuck according to the present invention.

FIG. 2 is a sectional view of a conventional double-jaw chuck.

FIG. 3 is a sectional view of a conventional wide-width chuck.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base film of female nail 2 Base film of male nail 3 Female nail 4 Female nail 5 Central nail of female nail 6 Hook of female nail 7 Hook of female nail 8 Male nail 9 Male nail 10 Hook of male nail Part 11 Hook-shaped part of male nail 12 Ear part or film of female nail 13 Ear part or film of female nail 14 Ear part or film of male nail 15 Ear part or film of male nail a Base width of female nail b Female nail Height c Male nail base width d Male nail height α Female nail angle β Male nail angle

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B29D 5/00 B65D 33/00-33/38

Claims (2)

(57) [Claims] 1. A. First Embodiment Three claws extend from the base of the base, and the cross section of the center claw is any shape with a low height, the tip bends inward on both sides to form a hook, and engages with the male claw to lock the lock. The ratio of the height including the thickness of the bottom base of the two claws on both sides to the width of the bottom base of the claw portion (height / width of the base) is 0.2 to 0.8. In range
And the width of the bottom base of the female nail of the chuck is 4.5 mm or less.
A certain female nail; Two claws extend from the other bottom base, and the ratio (height / base width) of the height including the thickness of the bottom base of the two claws to the width of the bottom base of the claw portion is 0.5 to 1.0, the tip of which is bent outward to form a male claw that forms a lock portion for engagement with the female claw, and the inner rise of the female claw and the male claw is 65-65 from the base . A string chuck having a chuck that extends inclining inward at an angle of 85 ° . 2. A container provided with male and female plastic chucks at its opening, comprising: Three claws extend from the bottom base on one side of the container opening, and the cross-section of the center claw has an arbitrary shape with a low height, and the tip bends inward on both sides to form a hook, The two claws are engaged to form a lock portion, and the ratio of the height including the thickness of the bottom base of the two claws on both sides to the width of the bottom base of the claw portion (height / width of the base) is 0. range .2～0.8 to <br/> Ah is, the width of the base foundation Mesutsume the chuck 4.5mm or less
B. a plastic chuck female nail is provided; Two claws extend from the bottom base on the opposite side of the container opening, and the ratio of the height including the thickness of the bottom base of the two claws to the width of the bottom base of the claw portion (height / width of the base). Is 0.5 ~
1.0, wherein the tip comprises a male claw that curves outward to form a lock for engagement with the female claw;
And the rise of the inside of the female nail and the male nail is 65-
A plastic zipper container that extends inclining at an angle of 85 ° inward.