JPH076106Y2 - Locking device for plastic containers - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention comprises a locking device for a plastic container or the like, which comprises a main body and a lid body that can be opened and closed, and both of which are locked by locking pieces. It is about.

[Conventional technology]

The main body and the lid of the plastic container are connected by a hinge so that they can be freely opened and closed, or they are opened and closed in a separated state. A locking piece integrally formed with a thin connecting portion is locked by engaging with an engaging portion provided on the other side.

In such a locking device for a plastic container, there is a problem that a thin connecting portion for flexibly connecting the locking piece to the molded container of the container breaks due to fatigue failure due to repeated bending.

On the other hand, conventional locking devices are disclosed in Japanese Utility Model Laid-Open Nos. 56-10045 and 56-10043. And the connecting part of the former is of uniform thickness and thinner than the other parts, and its both ends are curved inward. A thick reinforcing portion is formed.

[Problems to be solved by the device]

All of the above-mentioned conventional ones have some improvement in the repeated bending life of the connecting part, but are inferior in the restoring property after the torsional deformation stress is applied, and the uniform locking work for the engaging part is hindered, and the normal locking is achieved. It did not go into the state, and it sometimes slipped when an impact force was applied.

The present invention has been made in view of the above, and the repeated bending life of the connecting portion is further improved as compared with the above-mentioned conventional one, and the resilience to the torsional deformation stress is good, and the locking work is always performed correctly, An object of the present invention is to provide a locking device for a plastic container or the like that does not come off.

[Means for Solving the Problems]

In order to achieve the above object, a locking device for a plastic container or the like according to the present invention can be opened and closed, and one of a pair of molded bodies such as a main body and a lid body molded of plastic is provided with a thin wall. In a locking device such as a plastic container in which a locking piece is integrally molded via a connecting part and an engaging part for engaging the locking piece is provided on the other molded body, both end parts of the connecting part are engaged. It is formed so as to widen toward the width of the stopper.

[Action]

The pair of molded bodies are locked by bending the locking piece in a state where the pair of molded bodies such as the main body and the lid are closed, and engaging the protrusion of the hook portion of the locking piece with the engaging portion. At this time, the connecting portion of the locking piece is bent without stress concentration at both ends thereof. Further, at this time, even if a torsional deformation stress acts on the locking piece, it is restored and engaged in a normal state.

〔Example〕

 An embodiment of the present invention will be described with reference to the drawings.

In the figure, 1 is a main body, 2 is a lid, both of which are made of a thermoplastic material such as polyethylene or polypropylene, and have a hollow double wall structure by blow molding, and the openings of both are engaged with each other. The lid 2 is fitted in the main body 1 so as to be openable and closable. A locking piece 3 is integrally formed on one side of the lid body 2, and the locking piece 3 is formed on one side of the main body 1.
An engaging portion 4 with which the hook portion 3a is engaged is provided.

The locking piece 3 is connected to the lid body 2 side by a thin connecting part 5, but both ends of the connecting part 5 are wider in width toward the end of the width of the locking piece 3. ing. Both ends 5a, 5a of the connecting portion 5 are thicker than the other portions 5b. The thick portion is stepwise thickened outside the connecting portion 5. In a normal use example, the thickness of the central portion 5b of the connecting portion 5 is 0.1 to 0.2 mm, and the thickness of both end portions 5a is 1.1 to 2.8 times the thickness of the central portion.

Further, a projection 6 that engages with the engaging portion 4 is provided at the tip of the hook portion 3a of the locking piece 3, but this projection 6 is provided only at the center portion in the width direction of the hook portion 3a. There is.

Further, a plurality of convex ribs 7 are provided on the outer surface of the locking piece 3.

In the above structure, the locking piece 3 is bent in a state where the lid 2 is closed to the main body 1, and the projection 6 of the hook portion 3a of the locking piece 3 is engaged with the engaging portion 4 on the main body 1 side to be locked. . At this time, the locking piece 3 is rotated by the bending of the connecting portion 5, but since the connecting portion 5 is flared toward the lid 2 side from the locking piece 3, both end portions of the connecting portion 5 are formed. Stress concentration does not occur in 5a and 5a, and the repeated bending strength of this portion is improved.

Further, since both ends 5a, 5a of the connecting portion 5 are flared toward the end, the resilience to the torsional deformation stress is increased, and a twisting force acts during the locking operation of the locking piece 3 so that the connecting portion 5 Even if it is twisted and deformed, it is restored in the locked state, and the hook portion 3a of the locking piece 3 is engaged with the engaging portion 4 in a normal state.

Further, since the outer side surfaces of both end portions 5a, 5a of the connecting portion 5 which are flared toward the end are stepwise thickened, the strength of this portion is further improved. Note that this portion is thicker on the outer surface side than the other portions, and when the locking piece 3 is bent, the connecting portion 5 on the locking piece 3 side is bent and pulled and deformed as compared to the lid body 2 side. This thick portion does not hinder the flexibility when the locking piece 3 is bent, and the locking holding force also becomes strong.

The engagement between the locking piece 3 and the engaging portion 4 is achieved by the protrusion 6 engaging the engaging portion 3a.
Since it is performed in the central portion of the, the engagement between the two is performed firmly.

When the locking piece 3 is formed integrally with the lid body 2, it is compression-molded between the split molds, but since a plurality of convex ribs 7 are provided in this portion, it is unnecessary to perform extra molding during the compression molding. This molten resin is absorbed by the convex ribs 7, and it is possible to prevent the appearance of defective appearance such as a bent pattern on the surface of the locking piece 3. In addition to the container, the locking device of the present invention includes a tubular body such as a duct formed by a pair of semicircular half bodies, a plate body such as a double panel for locking two molded bodies in an overlapping manner. It can be implemented as a device for locking a pair of molded bodies.

[Effect of device]

According to the present invention, both ends of the connecting portion 5 of the locking piece 3 are connected to the locking piece 3.
Since the shape of the connecting portion 5 is widened toward the end, stress concentration does not occur at both ends 5a, 5a of the connecting portion 5, and the repeated bending strength of the connecting portion 5 is significantly improved. Further, since the connecting portion 5 has the above-described shape, the resilience to the torsional deformation stress is good, the engagement with the engaging portion 4 is always correctly performed, and the engaging portion 4 may be disengaged irreversibly. Without, reliability can be improved.

[Brief description of drawings]

The drawings show the essential parts of the present invention. Fig. 1 is a perspective view showing a state in which a locking piece is removed, Fig. 2 is a front view, and Fig. 3 is a cross section taken along line III-III in Fig. 2. FIG. 1 is a main body, 2 is a lid, 3 is a locking piece, 4 is an engaging portion, and 5 is a connecting portion.

Claims (1)

[Scope of utility model registration request] 1. A locking piece is integrally formed on one of a pair of molded bodies that can be opened and closed and is molded of plastic, such as a main body and a lid, through a thin connecting portion, and the other is molded. In a locking device for a plastic container having a body provided with an engaging portion for engaging the locking piece, both ends of the connecting portion are formed so as to widen toward the width of the locking piece. Locking device for plastic containers, etc.