JPH0321424B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a screw-on cap for containers that prevents overruns caused by over-turning when tightening the cap, accurately sets the tightening position, and prevents loosening once tightened. Regarding equipment.

Conventionally, in screw-on cap devices for plastic containers, the means for positioning the discharge port of the cap at a certain position on the container was done by adjusting the thread cutting position and the height of the container mouth. With this method, even if the thread height of the mold is adjusted accurately, there are many problems in that it cannot be set in a fixed position due to molding conditions, temperature, or variations in the finish of the container mouth. Vibrations and other shocks reduced the tightening torque and caused the cap to loosen, potentially causing the contents to leak, evaporation, and moisture damage. Therefore, as a means to solve this problem, for example, as described in Japanese Utility Model Publication No. 51-9539, a soft ring band of the cap is fastened to a hard ring-shaped protrusion on the neck of the container in the final position. Those with a structure in which the hem expands, climbs over, and attaches, and those with special
As described in Publication No. 26531, a protrusion of a soft cap slides on the side cam action surface of the neck and shoulder of the container while being widened, and is fitted into a recess on the side of the neck and shoulder of the container. However, in both cases, the skirt part of the soft cap deforms in the direction of expansion, so there is a risk that the original adhesion of the cap to the neck of the container may be impaired. Not only can it not be composed of materials,
The repeated deformation of expanding and contracting each time the device was installed caused problems such as cracking, permanent deformation, and fatigue failure.

For this reason, conventionally, for example, as described in Japanese Utility Model Application Publication No. 55-74659, two protrusions are connected at a predetermined interval on the upper surface of the neck part of the container to form a recess between them, while the other cap is A screw-in cap device for a container has been proposed in which a protrusion supported by a leaf spring having grooves on both sides of a thin horizontal plate is provided at the contact portion of the lower end surface of the container. Since the upper surface of the neck step of the container and the lower end surface of the cap are originally horizontal surfaces, the horizontal surfaces not only face the inclination of the screw as a corresponding step, but also provide a projection on top of the horizontal surface. Since the structure is such that the other protrusion passes over the part and fits into the recess,
These abutting protrusions constitute a step that is normally difficult to cross, and even if one side is bent like a leaf spring, there is a problem in that it cannot be expected to fit smoothly into each other or separate from each other. Ta.

SUMMARY OF THE INVENTION Therefore, the present invention provides a screw-in cap device for a container, in which a protrusion is provided on one side of the contact surface between the upper surface of the neck portion of the container and the lower end surface of the cap, and a recess into which the protrusion fits is provided on the other side. In the above, the protrusion and the recess have mutually abutting edges which are inclined inwardly with respect to the circumference of the cap in the screwing direction, and the edges gradually swell with respect to the inclination of the screw just before the recess. This is intended to provide a screw-in cap device for a container, which is provided with a flexible locking part that is elastically deformed and falls into the recess, and when the screw-in cap is tightened to the container, the screw-in direction of the circumference provided on one side is The protrusion, which has an edge inclined in the direction of biting inward, gradually rises against the inclination of the screw provided on the other side and comes into contact with a soft locking part that elastically deforms from an oblique direction, causing a wedge action. As the tightening resistance increases smoothly, over-tightening is prevented, and the protrusion smoothly falls into the recess connected to the locking part, and the protrusion and the edge inclined in the direction of biting into the recess come into contact with each other. Even if the protrusion touches the wall of the lower end of the container neck inside the recess and attempts to rotate it any further, the protrusion will be prevented from rotating, and the cap will be accurately positioned at a certain position on the container, and the cap will be rotated three times as much as normal. It is an object of the present invention to provide a screw-in cap device for a container that can prevent overrun even with an abnormal tightening torque of five times and prevent loosening.

The apparatus of the present invention will be described in detail with reference to the embodiments shown below. Reference numeral 10 is a container, and the outer periphery of the mouth frame 11 of the container 10 is provided with a threaded portion 12 into which a cap 20 is screwed. In the case of the embodiment, the threaded portion 12 has a thread cutting position.
The cap 20 is constructed as a double thread thread offset by 180 degrees, and a double thread thread 21 is similarly provided on the inner wall of the cap 20. A neck step 13 is integrally provided at the lower end of the mouth frame 11 of the container 10, and a cap 20 is attached to the upper surface of the neck step 13 at the screwing limit of the cap 20.
The lower end surface 22 of the cap 20 is in close contact with the upper end surface 14 of the opening frame 11 at the same time as the gasket 23 provided on the top surface of the cap 20.
It is configured so that it comes into contact with the 24 is a fixed frame portion of the gasket 23. Reference numeral 25 denotes a protrusion related to the device of the present invention provided on the lower end surface 22 of the cap 20, and a recess 15 provided on the upper surface of the neck step 13 of the cap 20.
It is constructed so that it can be screwed into the screw at the maximum position. Reference numeral 16 denotes an elastically deformable locking portion provided immediately before the recess 15 in the screwing direction A of the cap 20, and is configured in a shape that gradually rises against the slope S of the screw and falls into the recess 15. be. Reference numeral 17 denotes a guide surface provided on the upper surface of the neck step part 13 so as to communicate with the locking part 16 along the slope S of the screw from the position where the protrusion part 25 contacts the upper surface of the neck step part 13 during screwing. . Others, 26
is the discharge port of the cap 20.

Here, the edge 15a of the recess 15 is formed so as to bite inward with respect to the circumference in the screwing direction of the screw, as shown by arrow B in FIG. It is configured so that it is wedged inward by the tightening torque in the direction. In the case of the embodiment, the edge 15b of the recess 15 on the locking part side is also configured to be inclined in the same direction, and the protrusion 25 that fits into the recess 15 also has an edge 25a, which has a similar inclination. 25
It is equipped with b.

In the illustrated embodiment, the protrusion 25 and the recess 1
Although the combination with 5 is provided symmetrically at two locations around the mouth frame 11, it is possible to select and install one or three or more locations.

To explain how the device of the present invention is used based on the embodiment having the above configuration, when the cap 20 is screwed into the container mouth frame 11, the edge 2 inclined in the direction B that bites inward with respect to the circumference in the screwing direction
The lower surface of the protrusion 25 provided with the threaded portion 5a contacts the upper surface of the neck step 13 of the container 10, and the slope S of the threaded portion 12
It comes into contact with the locking part 16 while being guided by a guide surface 17 that has a gentle slope that is approximately the same as that of the guide surface 17 . Since the locking portion 16 gradually rises from the slope S of the screw, as the cap 20 is further screwed in, the protrusion 25 having the edge 25a inclined in the direction of biting inward becomes a soft elastically deformable protrusion 25. It comes into contact with the front corner of the locking part 16 from an oblique direction and rotates while being subjected to tightening resistance that smoothly increases due to a wedge action.The increase in tightening resistance prevents over-tightening, and when further tightened, the protrusion remains as it is. 25
falls smoothly into the recess 15 connected to the locking part 16, and the edges 25a, 15a, which are inclined in the direction B that bites into the inside of the protrusion 25 and the recess 15, come into contact with each other, and even if you try to turn the protrusion 25 any further, the protrusion 25
is prevented from rotating by coming into contact with the wall surface of the lower end of the container neck 11 inside the recess 15, and the cap is accurately positioned at a certain position on the container, and the cap is held at an abnormal tightening torque of 3 to 5 times the normal tightening torque. Overrun can be prevented even if the After the protrusion 25 is fitted into the recess 15, the edge 25b of the protrusion 25
Since the cap 20 comes into contact with the edge 15b of the recess 15 and is restrained, it becomes difficult to turn the cap 20 even in the loosening direction, and the cap 20 does not loosen. However, when strongly rotated in the loosening direction, the protrusion 25 elastically deforms and rotates in a direction that crushes the locking part 16.
Cap 20 can be removed from container 10.

Incidentally, if the pitch of the screws is set large as in the threaded portions 12 and 21 of the embodiment, not only can the cap be tightened with a small number of rotations, but also the recessed portion 15 and the locking portion 16 can be provided within a small rotational range. There is an effect that can be done. Further, by reducing the depth of the recess 15 and applying upward pressing force to the protrusion 25, it is possible to provide tight adhesion to the threaded parts 12 and 21.

As described above, according to the screw-in cap device according to the present invention, a protrusion is provided on one side of the contact surface between the upper surface of the neck step of the container and the lower end surface of the cap, and a recess into which the protrusion fits is provided on the other side. In the screw-on cap device for a container, the protrusion and the recess have mutually abutting edges that are inclined in a direction that bites inward with respect to the circumference of the cap in the screwing direction, and the protrusion and the recess have edges that touch each other in a direction that bites inwardly with respect to the circumference of the cap in the screw-in direction, and the protrusion and the recess have edges that abut each other and are inclined in a direction that bites inward with respect to the circumference of the cap in the screwing direction. Since it has a structure in which a flexible locking part that is elastically deformed gradually rises up against the cap and falls into the recess, when the screw-in cap is tightened to the container, the inner side with respect to the circumference in the screw-in direction provided on one side. The protrusion, which has an edge inclined in the direction of biting into the screw, gradually rises against the inclination of the screw provided on the other side and comes into contact with a soft locking part that elastically deforms from an oblique direction, causing a wedge action. The tightening resistance increases smoothly and falls smoothly into the recess connected to the locking part, so the increase in tightening resistance has the effect of preventing over-tightening. The edges slanted in the direction of biting touch each other,
Even if you try to turn it further, the protrusion comes into contact with the wall at the lower end of the container neck inside the recess and is prevented from rotating.
It has the effect of accurately positioning the cap at a certain position on the container, and when the protrusion fits into the recess, the tightening torque is 3 to 5 times stronger than normal due to the reaction of the cap's tightening force. It has the effect of preventing overrun even if it acts.

Furthermore, once positioned, the protrusion and the recess fit together to prevent the cap from loosening easily, but when the cap is loosened, the flexible locking part is elastically deformed and the protrusion leaves the recess. It has the effect of making it possible.

In the above description, the protrusion is provided on the cap and the recess is provided on the container, but it goes without saying that a configuration in which these are provided in reverse is also within the scope of the present invention.

[Brief explanation of the drawing]

FIG. 1 is a partially longitudinally sectional front view showing a main part of an embodiment of the apparatus of the present invention, and FIG. 2 is a plan view of the main part. 10: Container, 11: Mouth frame, 12: Threaded part, 1
3: neck step, 15: recess, 15a: edge of recess, 16: loosening stopper, 20: cap, 21:
Threaded portion, 25: Projection, 25a: Edge of projection, 26: Discharge port.

Claims (1)

[Claims] 1. In a screw-in cap device for a container, in which a projection is provided on one side of the contact surface between the upper surface of the neck step of the container and the lower end surface of the cap, and a recess into which the projection fits is provided on the other side, the projection and a concave portion having mutually abutting edges that are inclined in a direction that bites inward with respect to the circumference of the cap in the screwing direction, and elasticity that gradually rises against the inclination of the screw immediately before the concave portion and falls into the concave portion. A container screw cap device that is equipped with a deformable soft locking part.