Cap

Abstract

To provide a cap which can properly operate a check valve without deforming or damaging a valve seat formed at a boss at the time of release of injection molding, prevents generation of foam at the time of discharge of a content, and prevents the content from a nozzle from overflowing when a lid body is closed after discharge.SOLUTION: A cap 1 includes: a cap body 21; a lid body 22 integrally formed at the cap body 21; and a check valve 71 having an annular valve part 81, an annular seal part 82 whose vertical cross section is substantially rectangular, and an annular partition wall part 85 formed between the valve part 81 and the seal part 82. By forming a circulation groove 96 on an inner peripheral surface of the annular valve part 81 of the check valve 71, even in a state where the communication of an upstream chamber 3 and a downstream chamber 4 is cut off, via the circulation groove 96, a content 2 remaining in the downstream chamber 4 can be always returned into a container 10. Thereby, after use, the content 2 hardly remains in a discharge passage 62 of a nozzle 61, and even if the lid body 22 is closed and a plug 26 of the lid body 22 is fitted in a discharge port 64 of the nozzle 61, the content 2 can be prevented from overflowing from the discharge passage 62.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a cap that is attached to the mouth of a container that contains contents. [Background technology]

[0002] 2. Description of the Related Art Conventionally, containers have been known that are configured so that an appropriate amount of content is discharged from a nozzle of a cap by applying pressure to the container body to cause it to deform (see Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-200077 A [Patent Document 2] PCT / JP2022 / 034989 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the caps described in Patent Documents 1 and 2, when the pressure on the container is released after a small amount of content (one to several drops) is discharged, the volume of the downstream chamber that increases until the check valve seats on the valve seat is small, so the amount of content remaining in the nozzle discharge path that is sucked from the discharge path to the downstream chamber is small. Therefore, when the lid is closed, the plug of the lid fits into the nozzle discharge path, causing the content remaining in the discharge path to overflow and stain the outer surface of the nozzle.

[0005] In addition, the cap described in Patent Document 2 has a boss with multiple grooves, so that when the injection molding is released, the mold part for forming the multiple grooves comes into contact with the valve seat formed on the boss, causing the valve seat to deform and reducing the sealing performance. In addition, in the caps described in Patent Documents 1 and 2, the distance from the bottom dead center (i.e., the position where the check valve sits on the valve seat) to the valve opening point (i.e., the position where the check valve opens) is long, so the increase in the volume of the downstream chamber 4 becomes large before the check valve moves from the valve opening point to the bottom dead center, and the outside air is sucked in together with the contents remaining in the nozzle discharge path, causing the outside air to accumulate in the downstream chamber. This causes a problem that the outside air in the downstream chamber is mixed into the contents when the contents are discharged next time, causing air bubbles to form in the contents.

[0006] Furthermore, in the caps described in Patent Documents 1 and 2, the deformation range of the partition part of the check valve is relatively small, so when the container is squeezed to move the valve part of the check valve, and then the pressure on the container is released, the restoring force of the partition part is weak, making it difficult for the check valve to operate properly.

[0007] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a cap that can properly operate a check valve, prevents the generation of bubbles when the contents are dispensed without deforming or damaging the valve seat formed on the boss when the injection molding is released, and prevents the contents from overflowing from the nozzle when the lid is closed after dispensing a small amount. [Means for solving the problem]

[0008] As a means for solving the above-mentioned problems, the invention described in claim 1 is a cap to be attached to the mouth of a container for accommodating contents, the cap body including a ceiling portion attached to the mouth and closing the mouth portion, a nozzle having a discharge passage penetrating the ceiling portion and projecting upward from the ceiling portion, a boss projecting from the underside of the ceiling portion and having a small diameter cylindrical portion on the base end side, a large diameter cylindrical portion having a bulging portion with an expanded diameter on the tip end side, and an intermediate portion connecting the small diameter cylindrical portion and the large diameter cylindrical portion, an annular seal portion attached liquid-tightly to the underside of the ceiling portion of the cap body, and a small diameter sealing portion through which the boss is inserted and which can move in the axial direction of the boss to be seated on and removed from the outer circumferential surface on the downstream side of the bulging portion. The cap has an annular valve portion, and a flexible partition portion formed integrally between the sealing portion and the valve portion and dividing the inside of the mouth portion into an upstream chamber inside the container and a downstream chamber communicating with the discharge path of the nozzle, a check valve that opens when subjected to pressure inside the container to connect the upstream chamber and the downstream chamber, and a lid body attached to the cap body and capable of opening and closing the nozzle, wherein the inner diameter of the small-diameter annular valve portion is approximately the same as the outer diameter of the middle portion of the boss, and the check valve is separated from the bulge portion by squeezing the container, and when the annular valve portion moves to the small-diameter cylindrical portion, a flow path connecting the container and the upstream chamber is formed. In the cap of this section, the cylindrical boss is formed so that its outer diameter increases from the base end to the tip end. Therefore, when the cap is forcibly removed from the injection molding, the outer peripheral surface downstream of the bulge portion of the boss (the portion that becomes the valve seat) is not deformed or damaged, and the sealing performance with the valve portion is not reduced. In addition, since it is composed of only two parts, the cap body and the valve body of the check valve, the number of components is small, which reduces manufacturing costs and improves productivity by reducing assembly man-hours.

[0009] The invention described in claim 2 is characterized in that the movement distance of the annular valve portion of the check valve from the position where it seats on the outer peripheral surface downstream of the bulge portion to the position where it reaches the intermediate portion of the boss is a distance that allows only the contents remaining in the nozzle discharge path to be sucked in. In the cap according to this aspect, the increase in the volume of the downstream chamber can be regulated by regulating the distance that the annular valve portion of the check valve moves from the position where it reaches the middle part of the boss to the position where it seats on the outer peripheral surface of the downstream side of the bulge after the container is released from the compression. This makes it possible to suck in only the contents remaining in the nozzle discharge path, making it difficult for outside air to be sucked in, and preventing outside air from being mixed into the contents the next time the contents are discharged.

[0010] The invention described in claim 3 is characterized in that a connecting passage having a small flow path area is formed in the annular valve portion, the partition portion or the bulge portion of the boss of the check valve, which constantly connects the upstream chamber and the downstream chamber. In the cap according to this aspect, by forming a communication passage in the annular valve portion of the check valve, the partition portion, or the bulge portion of the boss, the contents remaining on the nozzle side, i.e., the downstream chamber side, can be efficiently returned to the container via the communication passage. This makes it difficult for the contents to remain in the nozzle discharge path even when a small amount is discharged, and makes it difficult for the contents to overflow from the nozzle when the lid is closed.

[0011] The invention described in claim 4 is characterized in that the cap body comprises an outer tube portion provided on the outer peripheral edge portion of the ceiling portion and fitted onto the outside of the mouth portion, an inner tube portion provided on the underside of the ceiling portion and concentrically arranged inside the outer tube portion, and a rib provided on the underside of the ceiling portion and concentrically arranged inside the inner tube portion, a seal retaining groove for keeping the annular seal portion liquid-tight is formed between the inner tube portion and the rib, and a communication passage having a small flow path area is formed at the portion where the annular seal portion of the check valve and the seal retaining groove abut, constantly connecting the upstream chamber and the downstream chamber. In the cap according to this aspect, a seal retaining groove is formed between the inner tube of the cap body and the rib, thereby keeping the annular seal liquid-tight. Also, a communication passage is formed at the portion where the annular seal of the check valve and the seal retaining groove come into contact, so that the contents remaining on the downstream chamber side can be efficiently returned to the container via the communication passage. This makes it difficult for the contents to remain in the nozzle discharge path even when a small amount is discharged, and makes it difficult for the contents to overflow from the nozzle when the lid is closed.

[0012] The invention described in claim 5 is characterized in that the radial center of the discharge passage of the nozzle is eccentric to the opposite side of the hinge connecting the cap body and the lid body with respect to the radial center of the boss. In the cap of this embodiment, the radial center of the nozzle's discharge path is eccentric to the opposite side of the hinge that connects the cap body and the lid body with respect to the radial center of the boss, so that when the contents are discharged, the contents collide with the ceiling and flow into the nozzle's discharge path, thereby preventing the contents from being discharged with force.

[0013] The invention described in claim 6 is characterized in that the partition wall of the check valve has a wavy tapered surface. In the cap of this section, the partition portion of the check valve is an elastic body having a wavy tapered surface, so that it is flexible and has a large range of deformation. When the container is squeezed, the pressure makes it easy to move it toward the nozzle side, and when the pressure on the container is released, the restoring force makes it easy to return to the container side, so that the check valve can operate properly. Effect of the Invention

[0014] According to the present invention, it is possible to provide a cap that can operate a check valve properly, prevents the generation of bubbles when the contents are ejected without deforming or damaging the valve seat formed on the boss when the injection molding is released, and prevents the contents from overflowing from the nozzle when the lid is closed after ejecting a small amount. [Brief description of the drawings]

[0015] [Figure 1] 1 is a schematic diagram of a container fitted with a cap according to one embodiment of the present invention. [Diagram 2] FIG. 2 is a cross-sectional view taken along the line AA shown in FIG. [Diagram 3] 3(a) is a plan view of the check valve shown in FIG. 2, (b) is a cross-sectional view taken along line BB shown in FIG. 3(a), and (c) is an enlarged view of part C shown in FIG. 3(b). [Figure 4] FIG. 2 is an enlarged view of a main part in FIG. 1 and is a view for explaining the function of a valve body. [Diagram 5] FIG. 2 is a schematic diagram of the container shown in FIG. 1 in a tilted state. [Figure 6] 2A to 2C are diagrams illustrating the operation process of the cap illustrated in FIG. 1. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] A cap according to an embodiment of the present invention will be described with reference to the accompanying drawings. As shown in FIG. 1, the cap 1 is attached to the mouth 11 (container mouth) of a squeeze container 10 (hereinafter referred to as "container 10"). As shown in FIG. 2, the container 10 is a double container having an outer container 14 and an inner container 16. The inner container 16 and the outer container 14 are made of materials such as low-density polyethylene, linear low-density polyethylene, high-density polyethylene, polypropylene, etc., and the inner container 16 is formed to have a thinner wall thickness than the outer container 14. The inner container 16 is made peelable from the outer container 14 except for a part of it. A space 17 is provided between the outer container 14 and the inner container 16. The outer container 14 is provided with an intake part 18 that can draw air between the space 17 and the outside. The inner container 16 is peeled off from the outer container 14 as the content 2 in the inner container 16 decreases.

[0017] As shown in Fig. 2, the intake section 18 is fitted into the opening 14a formed in the outer container 14, and includes an intake body 19 having a communication passage 19a that connects the space 17 to the outside, and a ball valve 20. The intake body 19 includes a first valve seat 27a provided on the outside side of the communication passage 19a, and a second valve seat 27b provided on the space 17 side of the communication passage 19a, on which the ball valve 20 is seated. Here, when discharging the contents 2, the ball valve 20 is configured to seat on the first valve seat 27a and close the communication passage 19a, while after discharging the contents 2, the reduction of the contents 2 allows outside air to be sucked into the space 17 between the outer container 14 and the inner container 16.

[0018] The cap 1 includes a cap body 21, a lid body 22 formed integrally with the cap body 21, and a check valve 71. The cap 1 is made of a synthetic resin such as polypropylene (PP) or polyethylene (PE).

[0019] The cap body 21 has a disk-shaped ceiling portion 31 that closes the upper end opening of the mouth portion 11 of the container 10, an outer cylinder portion 41 provided on the outer peripheral edge of the ceiling portion 31 and fitted to the outside of the mouth portion 11, an inner cylinder portion 45 provided on the lower surface 32 of the ceiling portion 31 and concentrically provided on the inside of the outer cylinder portion 41 and fitted to the inside of the mouth portion 11, and an annular rib 37 provided on the lower surface 32 of the ceiling portion 31 and concentrically provided on the inside of the inner cylinder portion 45. When the cap body 21 is fitted to the mouth portion 11 of the container 10, the inner peripheral surface 42 of the outer cylinder portion 41 abuts against the annular convex portion 12 that protrudes radially outward from the mouth portion 11. Also, the outer peripheral surface 47 of the inner cylinder portion 45 abuts against the annular concave portion 13 that is recessed radially inward from the mouth portion 11.

[0020] The annular recess 13 is provided near the opening of the mouth portion 11, and the annular protrusion 12 is provided at a middle position in the axial direction (the "up-down direction" in FIG. 2) of the mouth portion 11. An annular protrusion 43 is provided on the inner peripheral surface 42 of the outer tube portion 41 and is engaged with the annular protrusion 12 of the mouth portion 11 to prevent the cap body 21 from moving in the removal direction relative to the mouth portion 11.

[0021] A cylindrical boss 51 with an open tip is provided protruding from the center (center) of the underside 32 of the ceiling portion 31, and a plurality of protrusions 35 are formed at predetermined intervals in the circumferential direction so as to surround the boss 51, and a plurality of protrusions 36 are formed at predetermined intervals in the circumferential direction so as to surround the plurality of protrusions 35. The plurality of protrusions 35 serve to restrict movement of an annular valve body 81 of a check valve 71, which will be described later, and the plurality of protrusions 36 serve to restrict movement of an annular partition portion 85 of the check valve 71 toward the downstream chamber 4.

[0022] The boss 51 is provided concentrically inside the inner cylindrical portion 45, and the outer diameter increases from the base end toward the tip end. The boss 51 includes a small diameter cylindrical portion 51a on the base end side, a large diameter cylindrical portion 51b on the tip end side, and a connecting cylindrical portion 51c which is an intermediate portion connecting the small diameter cylindrical portion 51a and the large diameter cylindrical portion 51b. The small diameter cylindrical portion 51a, the large diameter cylindrical portion 51b, and the connecting cylindrical portion 51c are an integrally formed cylindrical body. The large diameter cylindrical portion 51b has a bulging portion 52 formed on its outer circumferential surface. The bulging portion 52 has a tapered outer circumferential surface on the upstream side (container 10 side) so as to facilitate the assembly of the check valve 71. The bulging portion 52 also has an outer circumferential surface on the downstream side (ceiling portion 31 side) which holds the check valve 71 and functions as a tapered valve seat 72 for receiving the check valve 71. An upper end of the valve seat 72 of the bulging portion 52 smoothly connects to the outer circumferential surface of the connecting tubular portion 51c. The connecting tubular portion 51c is tapered from the upstream side to the downstream side.

[0023] The nozzle 61 has a discharge passage 62 that connects from the lower surface 32 to the upper surface 33 of the ceiling portion 31, and has a tubular portion 63 that protrudes axially upward from the upper surface 33 of the ceiling portion 31, and a discharge port 64 that expands in diameter axially upward from the upper end of the tubular portion 63. In addition, the radial center of the discharge passage 62 of the tubular portion 63 is eccentric to the radial center of the boss 51 on the opposite side to the hinge 23 that connects the cap body 21 and the lid body 22 (see FIG. 2).

[0024] The lid body 22 is for covering the upper surface 33 of the ceiling part 31 when not in use, i.e., when the contents 2 are not being discharged, and is connected to the outer tube part 41 via a hinge 23. The hinge 23 is provided on the opposite side of the nozzle 61 (the position farthest from the nozzle 61). The inner edge of the opening of the lid body 22 is provided with an annular protrusion 24 that is engaged with an annular claw part 34 provided on the upper end outer edge of the ceiling part 31. The lid body 22 has an inner tube part 25 that is coaxial with the cap body 21 when closed. The lower end of the inner tube part 25 is abutted against the upper surface 33 of the ceiling part 31 near the inner side of the claw part 34. The lid body 22 has a plug 26 provided on the inside of the inner tube part 25. The plug 26 closes the discharge port 64 of the nozzle 61 when the lid body 22 is closed.

[0025] 2, the check valve 71 allows the flow of the contents 2 (see FIGS. 5 and 6) from inside the container 10 to the nozzle 61 (outside the container 10), and is formed in a roughly disk shape with a through hole 95 in the center into which the boss 51 is inserted. The check valve 71 includes a small-diameter annular valve portion 81 on the inner periphery, an annular seal portion 82 with a roughly rectangular vertical cross section on the outer periphery, and an annular thin-film partition portion 85 formed integrally between the valve portion 91 and the seal portion 82.

[0026] The annular valve portion 81 has a generally rectangular cross section, and a seal surface 94 that seats on and separates from the valve seat 72 of the bulging portion 52 of the boss 51 is formed between the inner edge of the upper surface 92 and the inner edge of the lower surface 93. The inner diameter of the annular valve portion 81 is generally the same as the outer diameter of the connecting tube portion 51c of the boss 51. As shown in FIG. 3(c), the seal surface 94 of the valve portion 91 is an annular inclined surface that extends radially inward of the check valve 71 from the lower surface 93 to the upper surface 92, and a flow groove 96 (communication passage) having a small flow area that always allows the flow of the contents 2 is formed. The seal portion 82 is provided outside the lower end opening of the nozzle 61, and is kept liquid-tight by an annular seal retaining groove 83 formed between the inner tube portion 45 and the annular rib 37 of the cap body 21.

[0027] The annular partition portion 85 is a thin-walled portion (elastic body) formed with a wavy tapered surface that has flexibility to allow the annular valve portion 81 to move easily in the axial direction of the boss 51, and extends obliquely downward from the outer periphery to the inner periphery of the check valve 71, with one end connected to the inner periphery surface at approximately the center of the seal portion 82 and the other end connected to the upper outer edge of the valve portion 91. The annular partition portion 85 divides the inside of the inner cylinder portion 45 (inside the mouth portion 11 of the container 10) into an upstream chamber 3 on the container body 15 side (the "lower side" in FIG. 2) and a downstream chamber 4 that communicates with the discharge passage 62 of the nozzle 61.

[0028] 4, when the annular valve portion 81 is located at bottom dead center H0, i.e., when the annular valve portion 81 is seated on the valve seat 72 (when the sealing surface 94 is in close contact with the seating surface of the valve seat 72), the check valve 71 blocks communication between the upstream chamber 3 on the container body 15 side and the downstream chamber 4 on the nozzle 61 side. While the annular valve portion 81 moves (slides) from bottom dead center H0 to the valve opening point H1 (i.e., the position where the annular valve portion 81 reaches the connecting cylindrical portion 51c of the boss 51), the check valve 71 is in contact with the outer circumferential surface 53 of the large diameter cylindrical portion 51b of the boss 51, and therefore communication between the upstream chamber 3 and the downstream chamber 4 remains blocked.

[0029] Then, from when the annular valve portion 81 reaches the valve opening point H1 until it reaches the top dead center H2 (i.e., the position where the annular valve portion 81 reaches the small diameter cylindrical portion 51a (contacts the multiple protrusions 35)), a flow path 73 (see FIG. 4) is formed between the annular valve portion 81 and the boss 51, thereby communicating the upstream chamber 3 and the downstream chamber 4. The position of the top dead center H2 of the annular valve portion 81 is determined by the contact of the upper surface 92 of the annular valve portion 81 with the multiple protrusions 35 provided on the lower surface 32 of the ceiling portion 31. Also, the movement distance of the annular valve portion 81 from the position where it sits on the outer peripheral surface on the downstream side of the bulging portion 52 to the position where it reaches the middle portion of the boss 51, that is, the movement amount from the valve opening point H1 to the bottom dead center H0, is set approximately to a distance where only the contents 2 remaining in the discharge path 62 of the nozzle 61 can be sucked.

[0030] Next, a method of assembling the above-mentioned cap 1 will be described. First, the seal portion 82 of the check valve 71 is inserted (pressed) into the seal retaining groove 83 formed in the cap body 21. An annular protrusion 84 is provided on the inner peripheral surface 46 of the inner cylinder portion 45 to prevent the seal portion 82 from slipping out of the seal retaining groove 83. Next, the tip portion of the boss 51 is penetrated into the through hole 95 so as to expand the diameter of the through hole 95 of the check valve 71. At this time, since the outer peripheral surface on the tip side of the boss 51 is formed in a tapered shape, the tip portion of the boss 51 can be penetrated into the through hole 95 without damaging the seal surface 94 of the annular valve portion 81. This completes the attachment of the check valve 71 to the cap body 21. Either the step of inserting the seal portion 82 into the seal retaining groove 83 or the step of penetrating the boss 51 into the through hole 95 may be performed first.

[0031] Next, the operation of the cap 1 according to one embodiment of the present invention will be described. When discharging the liquid contents 2, such as liquid seasoning, lotion, etc., contained in the inner container 16 of the container 10 from the nozzle 61 of the cap 1, the user first opens the lid 22 of the cap body 11 to expose the nozzle 61. Next, in order to discharge the contents 2, the user tilts the container 10 as shown in FIG. 5. In this state, the user does not squeeze (pressurize) the container body 15 (outer container 14) of the container 10, so that the annular valve portion 81 of the check valve 71 remains seated on the valve seat 72, and communication between the upstream chamber 3 on the container body 15 side and the downstream chamber 4 on the nozzle 61 side is blocked. In addition, the ball valve 20 of the intake portion 18 is lifted off the second valve seat 27b of the intake body 19, and the space 17 is communicated with the outside via the communication passage 19a.

[0032] Next, the user squeezes the outer container 14 while there is air in the space 17 between the outer container 14 and the inner container 16, thereby denting the outer container 14. As a result, the air in the space 17 passes through the communication passage 19a of the intake body 19, pushing up the ball valve 20, which then seats on the first valve seat 27a, isolating the space 17 from the outside. When the outer container 14 is further pressurized, the pressure in the space 17 increases, the inner container 16 is compressed and elastically deformed, and the pressure in the inner container 16 increases. As a result, the pressure in the upstream chamber 3 increases, and the check valve 71 is subjected to the pressure of the upstream chamber 3, causing the annular valve portion 81 to separate from the valve seat 72. Here, while moving from bottom dead center H0 (see Figure 4) to valve opening point H1 (see Figure 4) while maintaining liquid tightness, the annular valve portion 81 is in contact with the outer peripheral surface 53 of the large diameter cylindrical portion 51b of the boss 51, so that communication between the upstream chamber 3 and the downstream chamber 4 remains blocked.

[0033] Then, the annular valve portion 81 passes through the valve opening point H1, thereby opening the check valve 71. As a result, the upstream chamber 3 and the downstream chamber 4 are communicated with each other via the flow path 73 formed between the annular valve portion 81 and the boss 51, and the content 2 in the container 10 (upstream chamber 3) is discharged from the discharge port 64 of the nozzle 61 to the outside of the container 10 via the flow path 73, the downstream chamber 4, the opening 65, and the discharge path 62 (see FIG. 6(a)).

[0034] Here, when the contents 2 are discharged from the discharge port 64 of the nozzle 61 to the outside of the container 10, the contents 2 flowing from the flow path 73 collide with the lower surface 32 of the ceiling portion 31, thereby preventing the contents 2 from being forcefully discharged from the discharge port 64 of the nozzle 61. In addition, the annular valve portion 81 comes into contact with the multiple protrusions 35 formed on the lower surface 32 of the ceiling portion 31, thereby reaching the top dead center H2 (see FIG. 4), and the movement of the annular valve portion 81 is restricted.

[0035] Next, when the user releases the pressurizing force on the outer container 14, the outer container 14 returns to its original state, the space 17 becomes negative pressure, the ball valve 20 leaves the first valve seat 27a, the space 17 communicates with the outside via the communication passage 19a, and air is introduced into the space 17. Then, as the outer container 14 returns to its original state, the inner container 16 also returns to its original state slightly, causing a slight negative pressure inside the inner container 16. After that, the annular partition portion 85 itself returns to its original state, and the annular valve portion 81 moves from the top dead center H2 toward the valve seat 72. Then, when the annular valve portion 81 passes the valve opening point H1 (see FIG. 5), the communication between the upstream chamber 3 and the downstream chamber 4 is blocked (see FIG. 6(b)).

[0036] Then, the contents 2 equivalent to the increase in the volume of the downstream chamber 4 from the point at which communication between the upstream chamber 3 and the downstream chamber 4 is blocked until the annular valve portion 81 is seated on the valve seat 72 is sucked from the discharge passage 62 of the nozzle 61 into the downstream chamber 4 (see Figure 6 (c)).

[0037] When discharging a small amount of the contents 2, the pressurizing force of the outer container 14 applied by the user is small, so that the inner container 16 is also not easily compressed, the annular valve portion 81 does not reach the top dead center H2, and the amount of change in the volume of the container 10 (downstream chamber 4) is small. Therefore, when the pressurizing force of the outer container 14 is released, the contents 2 remaining in the discharge passage 62 of the nozzle 61 are not easily returned from the discharge passage 62 of the nozzle 61 to the downstream chamber 4, but can be gradually returned by gravity into the container 10 via the flow groove 96 of the annular valve portion 81. As a result, the contents 2 can be prevented from overflowing from the discharge passage 62 of the nozzle 61 even when the lid 22 is closed.

[0038] The cap 1 according to one embodiment of the present invention provides the following advantages. The boss 51 and the nozzle 61 are arranged offset in the radial direction of the boss 51, in other words, the nozzle 61 is arranged on the outside of the boss 51 provided in the center of the ceiling portion 31, so that it is possible to integrally mold the elements except for the check valve 71, and the cap 1 can be constructed from two parts, the cap body 21 and the check valve 71. This reduces the number of parts and makes it possible to suppress the manufacturing costs of the cap 1. In addition, the number of assembly steps is reduced, so the productivity of the cap 1 can be improved.

[0039] Furthermore, in the cap 1 according to one embodiment, when the pressurization of the outer container 14 is released, the contents 2 in the nozzle 61 (discharge path 62) are sucked into the downstream chamber 4 (container 10), so that the contents 2 are less likely to remain in the discharge path 62 of the nozzle 61 after use. This makes it possible to prevent the contents 2 from overflowing from the discharge path 62 and to prevent the contents 2 from adhering to the periphery of the nozzle 61, even when the lid body 22 is closed and the plug 26 of the lid body 22 is fitted into the discharge port 64 of the nozzle 61.

[0040] Furthermore, in the cap 1 according to one embodiment, by forming a flow groove 96 in the annular valve portion 81 of the check valve 71, even if the communication between the upstream chamber 3 and the downstream chamber 4 is blocked after a small amount of the contents 2 is discharged, the contents 2 remaining in the discharge path 62 of the nozzle 61 and the contents 2 remaining in the downstream chamber 4 can be returned to the container 10 via the flow groove 96. This makes it possible to prevent the contents 2 from overflowing from the nozzle 61 when the lid 22 is closed.

[0041] In the cap 1 of one embodiment, the partition portion 85 of the check valve 71 is an elastic body having a wavy tapered surface, so that it is flexible and has a large range of deformation. When the container 10 is squeezed, the pressure makes it easy to move it toward the nozzle 61 side, and when the pressure on the container 10 is released, the restoring force makes it easy to return to the container 10 side, so that the check valve 71 can operate properly.

[0042] In the cap 1 of one embodiment, after the squeeze container 10 (outer container 14) is released, the distance that the annular valve portion 81 moves from the valve opening point H1 to the bottom dead center H0 is restricted to a distance that enables only the contents 2 remaining in the discharge path 62 of the nozzle 61 to be sucked in. This makes it difficult for outside air to be sucked in along with the contents 2 remaining in the discharge path 62 of the nozzle 61, and prevents outside air from being drawn into the contents 2 the next time the contents 2 are discharged.

[0043] In the cap 1 of one embodiment, when the contents 2 are ejected, the contents 2 flowing from the flow path 73 collides with the underside 32 of the ceiling portion 31 and flows into the ejection path 62 of the nozzle 61, thereby preventing the contents 2 from being ejected forcefully from the nozzle 61.

[0044] In the cap 1 of one embodiment, the cylindrical boss 51 is formed so that the outer diameter increases from the base end to the tip end, thereby preventing damage or deformation of the valve seat 72 of the bulge portion 52 of the boss 51 when the cap 1 is forcibly removed from the injection molding, and preventing a decrease in the sealing ability with the annular valve portion 81.

[0045] In the cap 1 according to one embodiment of the present invention, the flow groove 96 is formed in the annular valve portion 81 of the check valve 71, but a communication passage having a small flow area for constantly returning the contents 2 remaining in the nozzle 61 to the container 10 may be formed in the valve seat 72 of the bulging portion 52 of the boss 51 on which the annular valve portion 81 is seated or a communication hole (communication passage) having a small flow area for constantly returning the contents 2 remaining in the nozzle 61 to the container 10 may be formed in the annular partition portion 85. Furthermore, a communication passage having a small flow area for constantly returning the contents 2 remaining in the nozzle 61 to the container 10 may be provided in a part of the portion (contact surface) where the annular seal portion 82 of the check valve 71 and the annular seal retaining groove 83 of the cap body 21 come into contact with each other. A plurality of these communication passages may be formed at the same time.

[0046] In the cap 1 according to one embodiment of the present invention, an example has been given in which the cap 1 is applied to a double container (container 10) consisting of an outer container 14 and an inner container 16, but the present invention is not limited to this. For example, the cap 1 can also be applied to a tube-shaped container or the like that is easily deformed when the body is squeezed and is difficult to restore to its original shape even when the pressure is released. [Explanation of symbols]

[0047] 1...cap, 2...content, 3...upstream chamber, 4...downstream chamber, 10...container, 11...mouth, 15...container body, 21...cap body, 22...lid body, 31...ceiling portion, 51...boss, 51a...small diameter cylindrical portion, 51b...large diameter cylindrical portion, 51c...connecting cylindrical portion (middle portion), 52...bulge portion, 61...nozzle, 62...discharge passage, 71...check valve, 72...valve seat, 81...annular valve portion, 82...annular seal portion, 85...annular partition portion

Claims

1. A cap to be attached to the mouth of a container for accommodating contents, a cap body including a ceiling portion attached to the mouth portion and closing the mouth portion, a nozzle having a discharge passage penetrating the ceiling portion and projecting upward from the ceiling portion, and a boss projecting from the underside of the ceiling portion and having a small diameter cylindrical portion on the base end side, a large diameter cylindrical portion having a bulging portion with an enlarged diameter on the tip end side, and an intermediate portion connecting the small diameter cylindrical portion and the large diameter cylindrical portion; a check valve having an annular seal portion attached liquid-tightly to the underside of the ceiling portion of the cap body, a small-diameter annular valve portion through which the boss is inserted and which can move axially of the boss to seat and separate from the outer circumferential surface of the downstream side of the bulge portion, and a flexible partition portion formed integrally between the seal portion and the valve portion and dividing the inside of the mouth portion into an upstream chamber inside the container and a downstream chamber communicating with the discharge path of the nozzle, the check valve opening when pressure within the container is applied to communicate between the upstream chamber and the downstream chamber; a lid body attached to the cap body and capable of opening and closing the nozzle, an inner diameter of the small-diameter annular valve portion of the check valve is approximately equal to an outer diameter of an intermediate portion of the boss; A cap characterized in that when the check valve is separated from the bulge portion by squeezing the container and the annular valve portion moves to the small diameter cylindrical portion, a flow path connecting the container and the upstream chamber is formed.

2. 2. The cap of claim 1, A cap characterized in that the distance that the annular valve portion of the check valve moves from the position where it seats on the outer peripheral surface downstream of the bulge portion to the position where it reaches the intermediate portion of the boss is a distance that enables it to suck up only the contents remaining in the nozzle discharge path.

3. 2. The cap of claim 1, A cap characterized in that a connecting passage having a small flow path area that constantly connects the upstream chamber and the downstream chamber is formed in the annular valve portion, the partition portion, or the bulge portion of the boss of the check valve.

4. 2. The cap of claim 1, The cap body includes an outer cylinder portion provided on the outer peripheral edge portion of the ceiling portion and fitted to the outside of the mouth portion, an inner cylinder portion provided on the lower surface of the ceiling portion and concentrically disposed inside the outer cylinder portion, and a rib provided on the lower surface of the ceiling portion and concentrically disposed inside the inner cylinder portion, A seal retaining groove is formed between the inner cylinder portion and the rib to retain the annular seal portion in a liquid-tight state, a sealing groove for sealing the upstream chamber to the downstream chamber; a sealing passage for sealing the upstream chamber to the downstream chamber;

5. 2. The cap of claim 1, A cap, characterized in that a radial center of the discharge passage of the nozzle is eccentric to a radial center of the boss on the opposite side to a hinge connecting the cap body and the lid body.

6. 2. The cap according to claim 1, wherein the partition wall of the check valve has a wavy tapered surface.

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