The present application claims priority pursuant to 35 U.S.C. § 119 to Japanese Patent Application No. 2017-104125 filed on May 26, 2017 in the Japan Patent Office, the entire disclosure of which is herein incorporated by reference.
The present disclosure relates to an inner plug structure for a flexible container and a flexible container incorporating the inner plug.
A flexible container for storing fluid content, such as liquid or paste, has a cap and a neck portion. The cap or the like mounted to the flexible container in a manner continuous with a container body for storing the fluid. The neck portion has an opening therein as a fluid discharge outlet at its end. The flexible container may be, for example, a squeezable container to contain a paste condiment such as mayonnaise, a tube container to contain toothpaste, or a squeezable bottle to be used as, for example, a water bottle for supplying water during exercise.
In the flexible container, when the fluid accommodated in the container body is discharged, the container body is squeezed by a human hand or the like, thereby increasing the pressure within the container body to discharge the fluid from the opening at the tip of the neck portion. In the flexible container, such a discharge amount of the fluid is adjusted by making an adjustment to the squeezing force to the container body. In Japanese Patent Application Publication No. 2005-9506, a valve using a magnetic force of a permanent magnet is described in connection with the present sure.
The flexible container that contains a fluid as its contents usually has a cap to prevent leakage and volatilization of the fluid during storage. However, the flexible container, such as a tube container, cannot maintain an upright state in which its fluid discharge outlet is directed vertically upward. Thus, when the fluid is a liquid having a low viscosity and if the container in an opened state is tilted or turned upside down, the fluid leaks out. Even in a bottle-shaped container with a bottom, if the container in the opened state is laid on its side, the fluid leaks out.
Conceivably, a valve may be incorporated as an inner valve in the neck portion of the flexible container that does not require power to open like a solenoid valve does but one using the magnetic force of a permanent magnet as described in the above-mentioned Japanese Patent Application Publication No. 2005-9506. The valve described in Japanese Patent Application Publication No. 2005-9506 is a check valve, and includes a spherical valve element disposed on the upstream side of a flow path of the fluid, such as a gas or liquid. This valve uses the rim of the discharge outlet on the upstream side of the flow path as a valve seat. The valve element is seated against this valve seat to close the valve. When pressure exceeding a threshold value is applied to the valve element upstream to downstream in the flow path, the valve element opens against the attractive magnetic force of the permanent magnet. Such a conventional valve shifts swiftly from the closed state, in which the valve element is pressed against the outlet on the upstream side of the flow path, to the open state, due to the pressure of the fluid.
However, in such a flexible container, assuming that the pressure is adjusted by squeezing the container by hand, the fluid is discharged at a stroke when the pressure exceeds the threshold value, due to the operation of such a responsive valve. Further, since the container body is squeezed by hand, the pressure in the container body varies. Thus, it is difficult to precisely discharge a predetermined amount of the fluid, and a very small amount in particular.
Accordingly, an aspect of the present disclosure is an inner plug structure for a flexible container and a flexible container including the inner plug structure, which includes a valve mechanism capable of reliably preventing leakage of a fluid which is the contents of the container, even if the container in an opened state is laid on its side, as well as capable of precisely discharging a very small amount of the fluid on demand.
Another aspect of the present disclosure is an inner plug structure for a flexible container, the flexible container configured such that a hollow tubular neck portion having its axis in a vertical direction is connected to a container body, the neck portion having an opening at an top thereof, the container body made of a flexible material to contain a fluid therein, the inner plug structure comprising: a tubular inner plug including a hollow portion therein, the hollow portion having its axis in the vertical direction; a valve element made of a material capable of being attracted by a magnetic force, the valve element being accommodated in the hollow portion of the inner plug so as to be movable in the vertical direction; a valve seat to support the valve element from below, in a closed valve state; and a permanent magnet disposed below the valve seat, the inner plug structure being configured to be mounted to the neck portion, wherein the hollow portion of the inner plug opens downward while maintaining a shape of its cross section orthogonal to the axis, as well as the hollow portion has a discharge outlet for the fluid that opens in its top surface on its top side , the discharge outlet having an opening shape included in the shape of the cross section, a planar shape of the valve element when viewed from above is included in the shape of the cross section of the hollow portion while including the opening shape of the discharge outlet, the valve seat includes a recessed portion in its upper surface, the recessed portion having a periphery whose shape is along the planar shape of the valve element, a tubular flow path is formed to open downward extending from an opening provided inside the recessed portion, through a region in which the permanent magnet is disposed, in the closed valve state, a void is formed between the valve element and the upper surface of the recessed portion, while the valve element contacts the periphery of the recessed portion, the valve element is always attracted toward the valve seat by the permanent magnet, and when a pressure equal to or greater than a predetermined value is applied, by the fluid in the container, to a bottom surface of the valve element, an open valve state is brought about, and when the pressure is smaller than the predetermined value, the valve is closed, the predetermined value being greater than an attractive force exerted between the valve element and the valve seat, and in the open valve state, the valve element is movable in a range from a position thereof in the closed valve state to a position thereof when contacting the inner periphery of the discharge outlet.
In the inner plug structure for a flexible container, it is preferable that the inner plug includes a cylindrical hollow portion therein, the hollow portion having its axis in the vertical direction, the valve element has a spherical shape, the permanent magnet is disposed around a circle concentrically with respect to the inner plug, the hollow portion of the inner plug opens downward while maintaining its internal diameter, and the hollow portion has a discharge outlet for the fluid that opens in its top surface on its top side, the discharge outlet having an opening diameter smaller than an internal diameter of the hollow portion, the valve element has a diameter greater than the opening diameter of the discharge outlet, and smaller than the internal diameter of the hollow portion, the valve seat includes a recessed portion having a circular periphery in its upper surface, the tubular flow path opens downward extending from an opening at a center of the recessed portion, through a hollow portion in which the annular permanent magnet is disposed, in the closed valve state, a void is formed between the valve element and the upper surface of the recessed portion, while the valve element contacts the circular periphery of the recessed portion concentrically.
Further, the inner plug structure for a flexible container can be such that the flow path is formed such that a hollow tubular shaft portion is connected to the bottom surface of the valve seat, the shaft portion opening downward while being inserted into the hollow portion in the permanent magnet, and the opening at the center of the recessed portion is connected to a hollow portion of the shaft portion.
The inner plug structure for a flexible container may be such that the permanent magnet is disposed below the valve seat, in a sealed state.
The present disclosure includes a flexible container configured such that a hollow tubular neck portion having its axis in a vertical direction is connected to a container body, the container body made of a flexible material to contain a fluid therein, the neck portion having an opening at an top thereof, and in an aspect of the flexible container according to the present disclosure, the inner plug structure is configured to be mounted to the neck portion, the inner plug structure includes a tubular inner plug including a hollow portion therein, the hollow portion having its axis in the vertical direction, a valve element made of a material capable of being attracted by a magnetic force, the valve element being accommodated in the hollow portion of the inner plug so as to be movable in the vertical direction, a valve seat to support the valve element from below, in a closed valve state, and a permanent magnet disposed below the valve seat, wherein the hollow portion of the inner plug opens downward while maintaining a shape of its cross section orthogonal to the axis, as well as the hollow portion has a discharge outlet for the fluid that opens in its top surface on its top side, the discharge outlet having an opening shape included in the shape of the cross section, a planar shape of the valve element when viewed from above is included in the shape of the cross section of the hollow portion while including the opening shape of the discharge outlet, the valve seat includes a recessed portion in its upper surface, the recessed portion having a periphery whose shape is along the planar shape of the valve element, a tubular flow path is formed to open downward extending from an opening provided inside the recessed portion, through a region in which the permanent magnet is disposed, in the closed valve state, a void is formed between the valve element and the upper surface of the recessed portion, while the valve element contacts the periphery of the recessed portion, the valve element is always attracted toward the valve seat by the permanent magnet, and when a pressure equal to or greater than a predetermined value is applied, by the fluid in the container, to a bottom surface of the valve element, an open valve state is brought about, and when the pressure is smaller than the predetermined value, the valve is closed, the predetermined value being greater than an attractive force exerted between the valve element and the valve seat, and in the open valve state, the valve element is movable in a range from a position thereof in the closed valve state to a position thereof when contacting the inner periphery of the discharge outlet.
Further, the flexible container can be such that the inner plug includes a cylindrical hollow portion therein, the hollow portion having its axis in the vertical direction, the valve element has a spherical shape, the permanent magnet is disposed around a circle concentrically with respect to the inner plug, the hollow portion of the inner plug opens downward while maintaining its internal diameter, and the hollow portion has a discharge outlet for the fluid that opens in its top surface on its top side, the discharge outlet having an opening diameter smaller than an internal diameter of the hollow portion, the valve element has a diameter greater than the opening diameter of the discharge outlet, and smaller than the internal diameter of the hollow portion, the valve seat includes a recessed portion having a circular periphery in its upper surface, the tubular flow path opens downward extending from an opening at a center of the recessed portion, through a hollow portion in which the annular permanent magnet is disposed, in the closed valve state, a void is formed between the valve element and the upper surface of the recessed portion, while the valve element contacts the circular periphery of the recessed portion concentrically.
In describing embodiments illustrated in the drawings, specific terminology is employed for the sake of clarity. However, the disclosure of this specification is not intended to be limited to the specific terminology so selected and it is to be understood that each specific element includes all technical equivalents that have a similar function, operate in a similar manner, and achieve a similar result.
Embodiments of the present disclosure will be described below with reference to the accompanying drawings. In the drawings used for the following description, components that are the same or similar are given the same reference numerals and the descriptions thereof may be omitted. Reference numerals unnecessary in making descriptions may also be omitted depending on the drawings.
An inner plug structure for a flexible container according to an embodiment of the present disclosure is fitted in a neck portion of a tube container for storing a fluid made of a cosmetic agent (cosmetic lotion, oil, emulsion, etc.), and acts as a check valve.
As illustrated in
An opening 14 in the top of the neck portion 12 is the fluid discharge outlet of the flexible container 10, and communicates with the inside of the container body 11 via the hollow interior portion of the neck portion 12. The container body 11 and the neck portion 12 may be integrally molded as a single integrated unit, or individually molded as separate components. The illustrated tube container 10 is constituted by the container body 11 and a molded portion in which the neck portion 12 and a shoulder portion 15 are a single integrated unit. The molded portion composed of the neck portion 12 and the shoulder portion 15 has larger wall thicknesses than the container body 11, but the material thereof can be made of the same material as that of the container body 11.
A procedure for manufacturing the tube container 10 involves, for example, molding a hollow cylindrical sleeve, which ends up as the container body 11, by extrusion molding or bonding of sheets; and by injection-molding forming in one end of the sleeve the single integrated unit composed of the shoulder portion and the neck portion. Then, the contents are injected from the other end of the sleeve, and this other end is sealed by welding, bonding, or the like, so that the tube container 10 filled with the contents is completed. Alternatively, the tube container 10 may be manufactured by joining the container body 11 and the aforementioned single integrated unit composed of the neck portion 12 and the shoulder portion 15 by ultrasonic welding, bonding, or the like.
The inner plug structure 1 according to an embodiment of the present disclosure includes, as illustrated in
Here, each of the relative upward direction and downward direction in an vertical direction in the tube container 10 and the inner plug structure 1 is defined, assuming that the vertical direction is the direction of an axis 100 of the hollow cylindrical neck portion 12 and the top side is the side on which the opening 14 of the tube container 10 is positioned in the neck portion 12. Further, in a state in which the inner plug structure 1 is mounted to the neck portion 12, the components (2 to 5) constituting the inner plug structure 1 are disposed coaxially with the neck portion 12. In the following description, in addition to the relative vertical direction, an upward direction and a downward direction based on gravity will be referred to as vertically upward and vertically downward separately from the above.
When the relative vertical direction is defined as described above, the inner plug 2 has a tiered hollow cylindrical shape in which a cylindrical body portion having a diameter smaller than a flat cylindrical head portion 22is connected to the lower side of the head portion 22, and a fluid discharge outlet 21 in the inner plug structure 1 is disposed in the center of the top of the head portion 22. The valve element support member 4 is formed such that a cylindrical shaft portion 42 is connected to the lower side of the valve seat 41 that supports the spherical valve element 3 from below. In the upper surface of the valve seat 41, a recessed portion 43 having a circular periphery and a conical inner surface is formed. In the center of the recessed portion 43, a through-hole 44 extending to the bottom of the shaft portion 42 is formed. Then, the annular permanent magnet 5 is fitted around the shaft portion 42 of the valve element support member 4. It should be noted that although a common magnet such as a ferrite magnet can be used as the permanent magnet 5, in the present embodiment a neodymium magnet having a strong magnetic force is used.
In a state in which the inner plug structure 1 is mounted to the tube container 10, in the inner plug structure 1 according to the present embodiment, a bottom surface 24 of the head portion 22 of the inner plug 2 contacts a top surface of the neck portion 12. In this state, only the head portion 22 of the inner plug 2 is exposed outside the neck portion 12, while the body portion 23 of the inner plug 2, the valve element support member 4, and the permanent magnet 5 below the head portion 22 are inserted into the neck portion 12. Further, the spherical valve element 3 is accommodated within a hollow portion 25 of the inner plug 2.
Next, the components and structure of the inner plug structure 1 according to an embodiment of the present disclosure will be described more specifically with reference to
The hollow tubular shaft portion 42 having a diameter smaller than the valve seat 41 is formed under the valve seat 41 of the valve element support member 4. An external diameter φD5 of the shaft portion 42 is equal to or slightly larger than an internal diameter of a hollow portion 51 in the annular permanent magnet 5. Accordingly, the permanent magnet 5 is fitted around the shaft portion 42 in a fitted state. It should be noted that two recessed portions 16 around the axis 100 are formed, at two upper and lower positions, on the inner surface of the neck portion 12 in the tube container 10. The projections (26, 45) respectively formed on the side surfaces of the body portion 23 and the valve seat 41 engage these recessed portions 16 a so that the inner plug structure 1 mounted to the neck portion 12 is not easily removed. Alternatively, the inner plug structure 1 may be mounted to the neck portion 12 by welding or bonding.
As illustrated in
As noted above, the spherical valve element 3 is accommodated within the hollow portion 25 of the inner plug 2. A diameter φD7 of the valve element 3 is larger than an opening diameter φD8 of the discharge outlet 21 in the inner plug 2, and is smaller than an internal diameter φD6 of the hollow portion 25 in the inner plug 2. Further, in the inner plug structure 1, the valve is closed by causing the valve element 3 to contact the circular periphery of the recessed portion 43 of the valve seat 41 concentrically. In the present embodiment, the valve element 3 contacts the inner surface of the recessed portion 43. Alternatively, the valve element 3 may be made to contact the periphery of the recessed portion 43. In the closed valve state, a top position P1 of the valve element 3 is lower than a vertical position P2 of a top surface 27 in the hollow portion 25 of the inner plug 2. Thus, the valve element 3 is movable in the vertical direction in a range between a position P3 as its upper limit of movement, at which the valve element 3 contacts the inner rim of the discharge outlet 21 as indicated by a dotted circle in the drawing, and the position P1 in the closed valve state.
In the inner plug structure 1, the valve element 3 comes in contact with the inner surface of the recessed portion 43 by an attractive force from the permanent magnet 5, which brings about the closed valve state. When the valve element 3 is biased to the discharge outlet 21 side by a force greater than the attractive force from the permanent magnet 5, the valve element 3 and the periphery of the recessed portion 43 of the valve seat 41 are separated, thus opening the valve. In the open valve state, since the internal diameter φD6 of the hollow portion 25 in the inner plug 2 is greater than the diameter φD7 of the valve element 3, a fluid discharge path is formed from the inside of the container body 11 to the discharge outlet 21 of the inner plug 2.
Note that the recessed portion 43 in the valve seat 41 is formed such that a void 46 is created between the upper surface of the recessed portion 43 in the upper surface of the valve seat 41 and the lower surface of the valve element 3 when the valve is closed by contact between the spherical valve element 3 and the inner surface of the recessed portion 43. Further, the valve element 3 is always attracted downward by the magnetic force of the permanent magnet 5. Thus, the closed valve state is maintained such that the valve element 3 is stuck to the valve seat 41 by the magnetic force of the permanent magnet 5, as long as no pressure equal to or greater than a predetermined value is applied thereagainst upward from below. When pressure equal to or greater than the predetermined value is applied against the lower surface, the valve element 3 can be moved only within the aforementioned range between the positions P1 and P3 described above. That is, the vertical position P2 of the top surface 27 of the hollow portion 25 and the opening diameter φD8 of the discharge outlet 21 are dimensioned such that, if the pressure applied upward onto the valve element 3 from below is smaller than the predetermined value, the valve element 3 is stuck to the valve seat 41 so that the valve is closed. Further, in addition preventing the valve element 3 from deviating, as a stopper of the valve element 3 the inner plug 2 also functions to facilitate discharging a very small amount of a fluid, with the vertical position P2 of the top surface 27 and the opening diameter φD8 of the discharge outlet 21 dimensioned accordingly.
Operation of Inner Plug Structure
The inner plug structure according to the present embodiment is operated, by virtue of the above-described components and structure, such that the closed valve state is maintained as long as no pressure equal to or greater than the predetermined value is applied upward against the valve element. Moreover, even in a case in which pressure equal to or greater than the predetermined value is applied and the open valve state is brought about, the valve quickly returns to the closed valve state once the pressure applied against the valve element becomes smaller than the predetermined value. Accordingly, even if the tube container in its opened state is laid on its side, the fluid content does not leak out, and when the body of the tube container is squeezed, a very small amount of the fluid can be precisely discharged.
When the container body is continuously squeezed and pressure equal to or greater than the predetermined value is applied against the valve element 3 by the fluid 6, the valve element 3 floats free of the valve seat 41 against the attractive force by the permanent magnet 5. At this time, a fluid discharge path forms, so that the fluid 6 reserved in the aforementioned void of the recessed portion 43 runs out between the valve element 3 and the inner surface of the hollow portion 25 in the inner plug 2 to flow into the discharge outlet 21 and is discharged from the discharge outlet 21 (
The amount of discharge of the fluid 6 in the sequence of this operation of opening and closing the inner plug structure 1 is a very small amount that is determined by the amount of the fluid 6 reserved within the void 46 in the recessed portion 43 at the start of a valve opening operation, and the amount of the fluid 6 that has flowed into the inner plug 2 in the short space of time until the valve element 3 contacts the inner rim of the discharge outlet 21 in the inner plug and the fluid discharge path is closed. Further, when the container body is continuously squeezed, the inner plug structure 1 repeats the valve opening operation by the pressure of the fluid 6 and the valve closing operation by the release of the pressure associated with the valve opening (
It should be noted that, even with fluid having the same viscosity, appropriate setting of a difference between the internal diameter φD6 of the hollow portion in the inner plug 2 and the diameter φD7 of the valve element 3 illustrated in
As such, in the inner plug structure 1 according to the present embodiment, it is possible to precisely discharge a very small amount of the fluid 6 without the need to finely adjust the force of squeezing the container body of the flexible container. Further, by appropriately setting the magnetic force of the permanent magnet 5 and the dimensions (φD2 to φD8, etc.) of the components (2 to 4) constituting the inner plug structure 1 illustrated in
There may be a case in which different fluids are contained in flexible containers having the same shape. Alternatively, there may be another case in which, even if the same fluid is contained in flexible containers having the same shape, variations in the mode of discharge (dripping, continuous discharging, etc.) are desired depending on the use of the fluid. In such cases, when adjusting the magnetic force of the permanent magnet 5 in addition to the size of the components, it is necessary to prepare the various permanent magnets 5 having the same shape but different magnetic forces. However, the permanent magnet 5 is expensive among the components constituting the inner plug structure 1, which results in increase in the manufacturing cost. The inner plug structure 1 according to an embodiment of the present disclosure, however, has a structure in which the annular permanent magnet 5 is disposed below the valve seat 41 of the valve element support member 4. Thus, the attractive force affecting the valve element 3 can be adjusted by changing the distance in the vertical direction between the valve element 3 and the permanent magnet 5 in the closed valve state, using the valve seats 41 having different thicknesses, which the permanent magnet 5 is disposed in contact with.
The external shape of the inner plug structure is not necessarily cylindrical as long as the hollow portion of the inner plug to accommodate the spherical valve element is cylindrical. The external shape of the inner plug structure may be any shape as long as it engages the inner surface of the neck portion. Further, the inner plug does not necessarily have a tiered tubular shape, as long as a discharge outlet for a fluid is formed in the top. Thus, the entire inner plug structure may be inserted in the neck portion.
The inner plug structure may be configured to be removable from the neck portion. That is, the inner plug structure may be provided as a single body separate from the flexible container. Accordingly, for example, if a plurality of inner plug structures having different states of discharge is prepared for a given flexible container, a user can select an appropriate inner plug structure depending on the type of a fluid and/or the use of the flexible container, and mount it to the neck portion of the flexible container.
In the embodiment described above, in order to prevent a fluid from contacting the permanent magnet, the shaft portion of the valve seat is inserted into the hollow portion of the annular permanent magnet, and a through-hole serving as a flow path for such contents is formed in the shaft portion. Alternatively, the valve element support member may be constituted only by the valve seat and the hollow portion of the annular permanent magnet may be used as a part of the flow path of the fluid, as long as the fluid is a material that does not cause a problem even if contacting the surface of the permanent magnet, or the surface of the permanent magnet is coated with a film that does not cause a chemical reaction even if contacting the fluid and the film does not easily wear out or peel off. Conversely, contact between the permanent magnet and the fluid may be prevented altogether.
The embodiment described above has a structure in which the fluid in the container body 11 does not easily contact the permanent magnet 5 directly since the bottom surface 17 of the neck portion 12 serves as a partition, as illustrated in
Further, the valve element support member 204 illustrated in
The permanent magnet need not have an integral annular shape as long as it is disposed so as to isotropically attract the spherical valve element. For example, as illustrated in
The inner plug structure according to embodiments of the present disclosure is applicable not only to a tube container but to flexible containers having various shapes as well, such as bottles.
Further, the inner plug structure according to embodiments of the present disclosure described above is mounted to the neck portion of the flexible container, such that the body portion of the inner plug and the valve seat of the valve element support member are inserted into the neck portion, while the inner plug structure uses the bottom surface (17 in
The inner plug structure 1e illustrated in
In an inner plug structure 1f illustrated in
In the embodiments described above, the valve element has a spherical shape, and the valve seat supports the spherical valve element, from below in a cone-shaped recessed portion that opens in a circular shape on its upper side. However, the shape of the valve element and the shape of the valve seat to support the valve element from below can be varied as appropriate, as long as the valve is closed when the valve element contacts the valve seat by a magnetic force, that is, the fluid discharge path from the inside of the container body to the discharge outlet of the inner plug can be closed. Further, the permanent magnet may be formed in any shape that conforms to the shape of the valve element and the shape of the valve seat to support the valve element from below.
In any case, a configuration may be such that the inner plug includes the hollow portion having its axis in the vertical direction, the valve element is made of a material capable of being attracted by a magnetic force, the permanent magnet is disposed blow the valve seat, the hollow portion of the inner plug opens downward while maintaining a shape of its cross-section orthogonal to the axis, a fluid discharge outlet opens in the top surface on the top side of the hollow portion, and further the discharge outlet has an opening shape included in the shape of the cross-section. Further, a configuration may be such that the planar shape of the valve element when viewed from above is included in the shape of the cross-section of the hollow portion in the inner plug, while including the opening shape of the discharge outlet, the valve seat includes, in its upper surface, the recessed portion having a periphery whose shape is along the planar shape of the valve element, a tubular flow path is formed to open downward extending from an opening provided inside the recessed portion, through a region in which the permanent magnet is provided, and in the closed valve state, a void is formed between the valve element and the upper surface of the recessed portion, while the valve element contacts the periphery of the recessed portion.
Number | Date | Country | Kind |
---|---|---|---|
2017-104125 | May 2017 | JP | national |