Pump-type discharge device

Abstract

To provide a pump type discharge device capable of quickly, easily, and surely discharging a content when used for the first time after being left in an unused state.SOLUTION: When a shaft-like valve element 36 descends together with a piston 31, a descending prevention part prevents the shaft-like valve element 36 from descent by engaging with the shaft-like valve element 36 before the piston 31 reaches the predetermined lower limit position. The descending prevention part may be a ball 46 of a ball valve 44 provided at a lower end part of a cylinder 19 containing the piston 31. Alternatively, the descending prevention part may be a projection projecting in a radial direction provided at the shaft-like valve element 36 so as to contact from above an upper end part of a locking body 40 that prevents the shaft-shaped valve element 36 from coming off upward.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a discharging device attached to a container for discharging its contents, and more specifically, to a pump-type discharging device configured to suck the contents from the container and discharge the contents under pressure by the vertical movement of a piston interlocking with a nozzle portion.

Background Art

[0002] According to this type of device, the contents can be discharged without opening, lifting, or tilting the container, and furthermore, a fixed quantity usually used can be discharged, etc., improving the convenience of the container or the product contained in the container. This type of device may be used for containers containing detergents such as viscous fluids or foamy fluids like shampoo, hand soap, and body soap as products, and an example thereof is described in Patent Document 1.

[0003] To briefly explain the configuration, the device described in Patent Document 1 includes an air cylinder attached to the mouth of a bottle, and a liquid cylinder is integrally formed radially inside and concentrically with the air cylinder. An air piston that slidably contacts the inner surface of the air cylinder and a liquid piston that slidably contacts the inner surface of the liquid cylinder are arranged concentrically and integrated. A flow path is formed through the liquid piston on the central side, and the flow path communicates with a liquid chamber defined by the liquid cylinder and the liquid piston and a nozzle. Further, in the flow path, there is an on-off valve that opens when the liquid piston moves toward the bottle side to communicate the nozzle and the liquid chamber, and closes when the liquid piston moves to the opposite side to block the communication between the nozzle and the liquid chamber. The on-off valve has a shaft-like member extending in the axial direction, and the shaft-like member is arranged in the above-described flow path. At one end (upper end) of the shaft-like member on the side opposite to the bottle, a valve body portion having a tapered shape with an outer diameter gradually increasing toward the side opposite to the bottle (upper side) is formed. On the other hand, a funnel-shaped valve seat portion that adheres closely to the valve body portion is formed at one end (upper end) of the liquid cylinder on the side opposite to the bottle. Furthermore, a spring is provided to push up the liquid piston and return it to its original position.

[0004] Therefore, when the pushing down of the liquid piston via the nozzle portion is released, the spring pushes up the liquid piston, causing the valve seat portion and the valve body portion to adhere closely and closing the on-off valve, and at the same time, the liquid piston is held at the upper limit position. In this way, the shaft-like member functions to cause the valve seat portion of the liquid piston pushed up by the spring to adhere closely to the valve body portion to close the on-off valve and to regulate the upward movement of the liquid piston. Therefore, it may be configured not to move upward. On the other hand, since the valve portion of the shaft-like member needs to contact the hole portion and close the hole portion during the rising process after the liquid piston is pushed down, the shaft-like member needs to descend during the process of the liquid piston being pushed down to about the lower limit position. Therefore, the shaft-like member is movable downward.

Prior Art Documents

Patent Documents

[0005] Patent Document 1 Japanese Patent No. 5435794 Summary of the Invention Problems to be Solved by the Invention

[0006] When no pressing force is applied to the above-described nozzle portion, since an upward pressing force by a spring is constantly applied to the liquid piston, the valve seat portion provided on the liquid piston and the valve body portion provided at the upper end portion of the shaft member are in close contact with each other. These liquid pistons, shaft members, or valve seat portions and valve body portions are usually made of synthetic resin such as thermoplastic resin in view of requirements such as ease of manufacture. Therefore, if the valve seat portion and the valve body portion are in contact with each other for a certain period of time while a load is applied, they will be in a stuck state. In particular, since the contents such as a cleaning agent have not yet adhered to their contact surfaces due to the unused state, and the valve seat portion and the valve body portion are likely to soften because the temperature of the storage location is high, the valve seat portion and the valve body portion are likely to be in a stuck state in combination with the fact that they have a tapered shape.

[0007] When the nozzle portion is pushed down in such a so-called stuck state, not only the liquid piston is pushed down, but also the shaft member descends together with the liquid piston. That is, as described above, although the upward movement of the shaft member is restricted, it is movable downward. Moreover, in the case of the first use (pushing down) that has never been used in the past, only compressible air enters the liquid piston without the contents such as a cleaning agent. Therefore, even if the internal volume of the liquid cylinder decreases and the internal pressure increases due to the descent of the liquid piston, the pressure is not high enough to prevent the descent of the shaft member and peel the valve body portion from the valve seat portion, so the shaft member descends together with the liquid piston while remaining stuck to the liquid piston.

[0008] After pushing down the nozzle part in this way and then releasing the pushing force, the liquid piston is pushed up by the elastic force of the spring. Along with this, the internal volume of the liquid cylinder into which the liquid piston is inserted increases. In this case, although the air compressed by the descent of the liquid piston expands, the internal pressure of the liquid cylinder does not become negative pressure, so the contents cannot be sucked into the inside of the liquid cylinder.

[0009] Thus, at the start of use, even if the nozzle part is pushed down once or several times, a situation may occur where so-called dry firing occurs and the contents cannot be discharged. However, conventionally, due to requirements in terms of manufacturability and cost, the above-described basic configuration has been maintained, and there has been room for developing an effective means for eliminating the above-mentioned inconveniences at the start of use.

[0010] This invention has been made by focusing on the above technical problems, and aims to provide a pump-type discharge device with excellent convenience that can suppress so-called dry firing and immediately discharge the contents when first used after being stored at a high temperature in an unused state.

Means for Solving the Problems

[0011] In order to achieve the above object, the present invention provides a pump-type discharge device including: a cap attached to an upper opening of a container body for accommodating contents; a nozzle portion movably held up and down on the cap and having a discharge port for discharging the contents; a piston moving up and down together with the nozzle portion; a cylinder in which the piston closely fits, and the internal volume increases when the piston relatively rises to suck the contents and the internal volume decreases when the piston relatively descends to extrude the contents; a shaft-like valve body inserted into a hole formed through the piston in the vertical direction and prevented from coming out upward; and a valve portion provided at an upper end of the shaft-like valve body, closing the hole by closely fitting into the hole to define an upper limit position of the piston and opening the hole when the piston relatively descends. In the pump-type discharge device, the shaft-like valve body has a downward movement preventing portion that engages with the shaft-like valve body to prevent the downward movement of the shaft-like valve body before the piston reaches a predetermined lower limit position when the shaft-like valve body descends together with the piston.

[0012] In the present invention, the downward movement preventing portion may be a abutting portion provided inside the cylinder and abutting against a lower end portion of the shaft-like valve body.

[0013] Further, in the present invention, a suction port for sucking the contents by an increase in the internal volume of the cylinder is formed at a lower end portion of the cylinder, and a ball-shaped valve body for closing the suction port from the inside of the cylinder is provided movably up and down inside the cylinder, and the abutting portion may be constituted by the ball-shaped valve body.

[0014] And, in the present invention, a holder member for inserting a lower portion of the shaft-like valve body therein and engaging the shaft-like valve body in the upward direction to prevent upward detachment is provided inside the cylinder, and the downward movement preventing portion may be constituted by a radially protruding portion provided on the shaft-like valve body so as to abut against an upper end portion of the holder member from above.

Effects of the Invention

[0015] In the present invention, when the nozzle portion is pushed down with the cap attached to the container body, the piston descends inside the cylinder together with the nozzle portion, and the internal volume of the cylinder decreases. As a result, the internal pressure of the cylinder increases, so a force acts on the shaft-like valve body in a direction restricting movement, i.e., descent, toward the inside of the cylinder, and the piston descends relative to the shaft-like valve body. If the lower end portion of the cylinder is provided with a suction port and a ball-shaped valve body is placed thereon, the ball-shaped valve body is pressed against the suction port to close the suction port.

[0016] When the pushing down of the nozzle portion is released and the piston ascends together with the nozzle portion, the internal volume of the cylinder increases and its internal pressure decreases, and a suction action into the cylinder occurs. If the above-described ball-shaped valve body is provided, the ball-shaped valve body opens and the suction port opens, and the content is sucked into the cylinder from the inside of the container body. Then, when the nozzle portion is pushed down again, as described above, the piston descends relative to the shaft-like valve body, so that the valve portion formed at the upper end portion of the shaft-like valve body separates from the hole portion formed at the upper end portion of the piston and the hole portion opens. As a result, the content sucked into the cylinder is pushed out to the nozzle portion through the hole portion and discharged from the discharge port.

[0017] On one hand, for example, when the nozzle part is depressed for the first time in an unused state, if the valve part is fixed to the hole part, the axial valve body may descend as the piston descends by depressing the nozzle part. In that case, when the axial valve body descends to a predetermined dimension determined by design, the axial valve body engages with the downward movement prevention part, and its downward movement is restricted. After that, when the piston descends further, the fixation between the valve part and the hole part is released, and the hole part opens. Therefore, the pressure inside the cylinder becomes the same as the pressure of its environment. And since the valve part contacts the hole part and the hole part is closed during the process of the piston ascending, an inhalation action into the cylinder occurs due to the decrease in the internal pressure of the cylinder as the piston ascends. In the configuration provided with the ball-shaped valve body, as described above, the suction port opens, the content is inhaled into the cylinder, and then by depressing the nozzle part, the content is discharged from the nozzle part. In this way, after depressing the nozzle part once, the content can be surely discharged, suppressing so-called dry firing and improving the convenience of the discharge device or the discharge container to which this is attached.

Brief Description of the Drawings

[0018]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiments for Carrying Out the Invention

[0019] Figure 1 shows a cross-sectional view of a pump-type discharging device as an embodiment of the present invention. The pump-type discharging device shown here is a so-called pump former 1, which is configured to form bubbles by mixing a liquid content filled inside a bottle 2 corresponding to a container body in the present invention with air and discharge the bubbles. The pump former 1 is provided with a cap 4 that is detachably attached to the mouth portion 3 of the bottle 2 and is attached to the bottle 2 by the cap 4. Specifically, the mouth portion 3 is a cylindrical opening formed on the upper end side of the body portion of the bottle 2, and a male thread is formed on its outer peripheral surface. Also, a female thread that fits into the male thread is formed on the inner peripheral portion of the cap 4. That is, by screwing the mouth portion 3 into the cap 4, the pump former 1 is attached to the bottle 2.

[0020] As shown in Figure 1, the cap 4 includes an outer cylindrical portion 5 that covers the outside of the mouth portion 3 and has the above-mentioned female thread formed on its inner peripheral portion, and a short inner cylindrical portion 6 with an axial length that is inserted into the mouth portion 3. Therefore, the outer cylindrical portion 5 is a cylindrical shape larger than the outer diameter of the mouth portion 3, and the outer cylindrical portion 5 and the inner cylindrical portion 6 extend downward from the upper surface portion 7 of the cap 4 and are integrally formed so as to be located on the same concentric circle. Further, the central portion of the upper surface portion 7 is open, and a guide stem portion 8 is provided so as to surround the opening. The guide stem portion 8 is a cylindrical portion that extends upward from the upper surface portion 7 and is a portion integral with the upper surface portion 7. The nozzle portion 9 is held vertically movable by the guide stem portion 8.

[0021] The nozzle portion 9 is a portion for performing a pressing-down operation for discharging the content of the bottle 2, and includes a top surface portion 10 to which a pressing force is applied as a so-called nozzle head, a nozzle opening 11 corresponding to a discharge port for discharging bubbles, a cylindrical inner cylinder portion 12 in which a flow path P communicating with the nozzle opening 11 is formed, and a cylindrical outer cylinder portion 13 having a larger diameter than the inner cylinder portion 12 and formed concentrically with the inner cylinder portion 12. The nozzle opening 11 can have an appropriate shape according to design requirements and the like. In the example shown in Figure 1, it has a shape extending radially outward from the above-mentioned flow path P.

[0022] Further, each of the cylindrical portions 12 and 13 extends downward in FIG. 1 from the top surface portion 10 of the nozzle portion 9 in the axial direction, and the axial length of the inner cylindrical portion 12 is set longer than that of the outer cylindrical portion 13. Also, the outer diameter of the inner cylindrical portion 12 is set slightly smaller than the inner diameter of the guide stem portion 8, and thus, it can be inserted into the guide stem portion 8. Further, the inner diameter of the outer cylindrical portion 13 is set slightly larger than the outer diameter of the guide stem portion 8, and the guide stem portion 8 can be inserted therein. That is, by inserting the guide stem portion 8 between the inner cylindrical portion 12 and the outer cylindrical portion 13 in the radial direction, the nozzle portion 9 is guided by the guide stem portion 8 and the cylindrical portions 12 and 13 and is adapted to move in the axial direction. Also, a slight gap is formed between the outer peripheral surface of the inner cylindrical portion 12 and the inner peripheral surface of the guide stem portion 8, and between the outer peripheral surface of the guide stem portion 8 and the inner peripheral surface of the outer cylindrical portion 13, and these gaps serve as air flow paths, respectively. Air is introduced into an air cylinder described later through these air flow paths.

[0023] In the example shown in FIG. 1, a net holder 14 for forming uniform bubbles is disposed on the inner peripheral surface of the inner cylindrical portion 12. This net holder 14 is a cylindrical member, and nets (not shown) are respectively attached to both end portions in the axial direction. Also, the inner diameter of the inner cylindrical portion 12 in which the net holder 14 is inserted becomes narrower above the position where the net holder 14 is disposed, and the net holder 14 is held in a state of abutting against a stepped portion where its inner diameter changes in size. Then, as will be described later, the content foamed by being mixed with air passes through the net holder 14, whereby finely and uniformly sized bubbles are formed.

[0024] The cylinder member 15 is held inside the cap 4. As shown in FIG. 1, the cylinder member 15 is closely fitted to the outer peripheral side of the inner cylinder portion 6 and integrated with the cap 4. The lower portion of the fitting portion of the cylinder member 15 fitted to the inner cylinder portion 6 has a slightly smaller diameter. Further, a flange 16 extending outward in the radial direction is formed at the upper end portion of the cylinder member 15. The outer diameter of the flange 16 is about the outer diameter of the tip portion of the mouth portion 3 (the outer diameter of the opening of the mouth portion 3) or slightly larger than that. A sealing material 17 is sandwiched between the tip portion (open end) of the mouth portion 3 and the lower surface of the flange 16 (the lower surface of the flange 16 in FIG. 1) to ensure airtightness and liquid tightness. By attaching the cap 4 to the mouth portion 3 with screws, the flange 16 and the sealing material 17 are sandwiched between the upper surface portion 7 of the cap 4 and the tip portion of the mouth portion 3 to seal the mouth portion 3.

[0025] Regarding the configuration of the cylinder member 15 in more detail, the cylinder member 15 shown here is integrally formed with an air cylinder 18 which is a part of an air pump for pushing air out to the nozzle portion 9 and a liquid cylinder 19 which is a part of a liquid pump for pushing the content out to the nozzle portion 9. The air cylinder 18 is a large-diameter portion formed in the cylinder member 15 below the fitting portion described above in the axial direction. A first intake hole 20 for taking air into the inside of the bottle 2 is formed through the upper end side portion of the peripheral wall portion constituting the air cylinder 18 in the plate thickness direction of the air cylinder 18.

[0026] On one hand, the liquid cylinder 19 is a cylindrical portion with a smaller diameter than the air cylinder 18 and is formed concentrically with the air cylinder 18. In the example shown in FIG. 1, the liquid cylinder 19 has a cylindrical shape in which the bottom of the air cylinder 18 is folded upward and the central portion thereof is further folded downward. That is, the liquid cylinder 19 and the air cylinder 18 are formed concentrically and slightly displaced in the axial direction, and at least a part of them overlaps with each other in the radial direction. In the example shown here, the liquid cylinder 19 is formed continuously with the air cylinder 18. The boundary portion between these cylinders 18 and 19 is, as shown in FIG. 1, a convex curved surface portion formed by curving the bottom of the air cylinder 18 so as to protrude upward in FIG. 1. When the flange of the liquid piston described later contacts this boundary portion, further movement (pushing) of the nozzle portion 9 and each piston is blocked. This position is the stroke end, i.e., the lower limit position, of the nozzle portion 9 and each piston when each piston is pushed into the bottle 2 side. The example shown in FIG. 1 shows the state where the nozzle portion 9 is at the upper limit position.

[0027] Inside the above-mentioned air cylinder 18, an air piston 21 that slides in the axial direction (the vertical direction in FIG. 1) while maintaining an airtight state on its inner peripheral surface is fitted. The air cylinder 18 and the air piston 21 constitute an air pump. The air piston 21 has a piston head 22 that divides the inside of the air cylinder 18 into upper and lower parts in FIG. 1, and a sliding portion 23 that is integrated with the piston head 22 and contacts the inner peripheral surface of the air cylinder 18. Of the two interiors partitioned by the piston head 22, the interior below the piston head 22 in FIG. 1 is an air chamber 24. The sliding portion 23 is formed in a cylindrical shape in the example shown in FIG. 1, and slidably contacts the inner peripheral surface of the air cylinder 18 while maintaining airtightness at two upper and lower locations of the cylindrical portion. And the sliding portion 23 opens and closes the above-mentioned first intake hole 20 by reciprocating in the axial direction.

[0028] At a predetermined radial position on the piston head 22, a second intake hole 25 for introducing air into the air chamber 24 is formed through the piston head 22 in the plate thickness direction. Further, in a portion radially inside the second intake hole 25 in the piston head 22, a check valve 26 is provided that communicates the air chamber 24 with the outside of the bottle 2 according to the internal pressure of the air chamber 24 and also communicates the air chamber 24 with a mixing chamber described later.

[0029] The check valve 26 is a member provided with a membrane-like (diaphragm-like) valve body that protrudes radially inward and outward at the lower end of a cylindrical portion that is formed to extend upward in FIG. 1 on the piston head 22. The portion that extends radially outward becomes the outer valve portion, and the portion that extends radially inward becomes the inner valve portion.

[0030] The outer valve portion covers the second intake hole 25 from the inside of the air chamber 24 so as to close the second intake hole 25 when the internal pressure of the air chamber 24 increases from the pressure outside the bottle 2 and to open the second intake hole 25 when the internal pressure of the air chamber 24 decreases from the pressure outside the bottle 2. That is, an air intake valve 27 for introducing or blocking outside air into the air chamber 24 is constituted by this outer valve portion.

[0031] Further, the inner valve portion is configured to communicate the air chamber 24 with the mixing chamber when the internal pressure of the air chamber 24 is higher than the pressure outside the bottle 2 and to block the communication between the air chamber 24 and the mixing chamber when the internal pressure of the air chamber 24 is lower than the pressure outside the bottle 2. That is, the inner valve portion is in contact with the flange of a liquid piston described later and is configured to open and close according to the pressure difference between the air chamber 24 and the mixing chamber. In this way, an air discharge valve 28 for supplying and also extruding the air in the air chamber 24 to the mixing chamber is constituted by the inner valve portion.

[0032] Further, at the center of the piston head 22 in the radial direction, a cylindrical portion 29 extending upward in FIG. 1 is integrally formed. The upper end side portion of the cylindrical portion 29 in FIG. 1 is closely fitted inside the lower side portion of the inner cylindrical portion 12 formed in the nozzle portion 9 described above, and is integrated with the nozzle portion 9. Further, the lower end portion of the net holder 14 described above is inserted inside the upper end portion of the cylindrical portion 29. In the example shown in FIG. 1, a rib portion is formed on the outer peripheral surface of one end of the cylindrical portion 29, and a concave groove portion that fits into the rib portion is formed on the inner peripheral surface of the inner cylindrical portion 12. By fitting of these rib portion and concave groove portion, the cylindrical portion 29 and the inner cylindrical portion 12 are firmly connected. Note that the cylindrical portion 29 and the inner cylindrical portion 12 may be connected by means such as screw fitting or stop fitting.

[0033] The inner diameter of the upper end portion of the cylindrical portion 29 is formed to be slightly larger than the outer diameter of the lower end portion of the net holder 14. Further, on the inner peripheral surface of one end portion of the cylindrical portion 29, below the portion with the larger inner diameter described above, one or a plurality of protrusion portions 30 protruding inward in the radial direction are formed. The protrusion portion 30 abuts against the lower end portion of the net holder 14 to hold the net holder 14, and when the nozzle portion 9 is pushed down, it contacts one end portion of an axially-shaped valve body described later to push and move the axially-shaped valve body. Further, in order not to particularly impede the flow of the content in the flow path P, the inner diameter of the protrusion portion 30 is set to approximately the inner diameter of the net holder 14. And as shown in FIG. 1, when the nozzle portion 9 is in the upper limit position, a clearance C is set between the upper end portion of the valve body portion of the axially-shaped valve body described later and the side surface of the protrusion portion 30 that contacts the upper end portion. The lower end portion of the net holder 14 is fitted into a fitting portion formed by the portion with the larger inner diameter and the protrusion portion 30 among one end portions of the cylindrical portion 29 described above. In this way, the air piston 21 and the nozzle portion 9 are integrated, and the net holder 14 is held in the flow path P between them. Therefore, when the top surface portion 10 of the nozzle portion 9 is pressed toward the bottle 2 side to push down the nozzle portion 9, the air piston 21 moves (descends) toward the bottle 2 side together with the nozzle portion 9, and the internal volume of the air chamber 24 partitioned by the air cylinder 18 and the air piston 21 decreases. Then, the inside of the air chamber 24 is pressurized, and the air inside the air chamber 24 is pushed out from the air chamber 24. Further, when the air piston 21 is pushed down toward the bottle 2 side by the amount of the clearance C described above, the protrusion portion 30 contacts the upper end portion of the valve body portion of the axially-shaped valve body to push down the axially-shaped valve body toward the bottle 2 side.

[0034] At the lower end of the cylindrical portion 29 in FIG. 1, the liquid piston 31 of the liquid pump is fitted. As shown in FIG. 1, the liquid piston 31 is formed in a cylindrical shape extending in the axial direction, and one end thereof (the upper end in FIG. 1) is fitted to the other end of the cylindrical portion 29. Specifically, a recess that is recessed in the axial direction is formed at the other end of the cylindrical portion 29 so that one end of the liquid piston 31 fits therein. The inner diameter of the recess is set to an inner diameter such that one end of the liquid piston 31 fits. Also, an air flow path (not shown) is formed between the recess and one end of the liquid piston 31. The space between the fitting portion of the other end of the cylindrical portion 29 and the liquid piston 31 in the axial direction and the net holder 14 fitted inside the cylindrical portion 29 is a mixing chamber 32 where air and the liquid content are mixed. One end of the above-described air flow path communicates with the flow path P in the cylindrical portion 29, and the other end communicates with the space partitioned by the liquid piston 31 and the air piston 21.

[0035] On the outer peripheral surface of the liquid piston 31, a flange 33 that protrudes outward in the radial direction is formed. As described above, the flange 33 is a portion that defines the lower limit positions of the air piston 21 and the liquid piston 31. Also, as shown in FIG. 1, when the nozzle portion 9 is in the upper limit position, the air discharge valve 28 contacts the upper surface of the flange 33. The other end of the liquid piston 31 is fitted to the inner peripheral surface of the liquid cylinder 19 so as to slide in the axial direction (the vertical direction in FIG. 1) while maintaining a liquid-tight state. Therefore, the above-described liquid pump is constituted by the liquid cylinder 19 and the liquid piston 31, and the cylindrical space formed by the liquid cylinder 19 and the liquid piston 31 is a liquid chamber 34. As described above, when the top surface portion 10 of the nozzle portion 9 is pressed toward the bottle 2 side to push down the nozzle portion 9, the liquid piston 31 moves toward the bottle 2 side together with the air piston 21, and the internal volume of the liquid chamber 34 decreases. Then, the inside of the liquid chamber 34 is pressurized, and the liquid inside the liquid chamber 34 is pushed out from the liquid chamber 34.

[0036] In addition, inside the liquid chamber 34, there are a return mechanism that returns the nozzle portion 9 and each piston to their original positions when the force pressing the nozzle portion 9 and each piston downward toward the bottle 2 side is released, and a valve mechanism that communicates the liquid chamber 34 with the inside of the bottle 2 in response to the pumping of the nozzle portion 9 and also communicates the liquid chamber 34 with the mixing chamber 32 and the flow path P. First, the return mechanism will be described. In the embodiment shown here, the return mechanism is configured to return the nozzle portion 9 and each piston 21, 31 by the elastic force of a coil spring (hereinafter simply referred to as a spring) 35. A spring receiving portion for fitting one end portion of the spring 35 is formed at the other end portion of the aforementioned liquid piston 31. The spring 35 is arranged in a compressed state below this spring receiving portion. Therefore, an elastic force that pushes upward acts on the liquid piston 31 constantly on the side opposite to the bottle 2 side (the upper side in FIG. 1).

[0037] The valve mechanism is an on-off valve that opens when pushing out the content from the liquid chamber 34 and closes when sucking up the content from the inside of the bottle 2 into the inside of the liquid chamber 34, and is provided at the upper end portion of the liquid piston 31. Specifically described, an axial valve body 36 is arranged along the central axis of the liquid cylinder 19 and the liquid piston 31 fitted therein. This axial valve body 36 is an axial member whose upper end portion is a valve body portion 37 and a retaining portion for preventing upward detachment is formed at the lower end portion, and its upper end portion protrudes above the liquid piston 31 through a hole formed at the upper end center portion of the liquid piston 31.

[0038] The valve body portion 37 is formed in a tapered shape with an outer diameter gradually increasing toward the upper side as shown in FIG. 1 as an example. On the other hand, the hole portion is a tapered hole having the same shape (or a similar shape) as the tapered shape of the valve body portion 37, and thus the tapered inner peripheral surface thereof serves as a valve seat portion 38. That is, the valve mechanism is configured such that the hole portion is closed when the valve body portion 37 contacts the valve seat portion 38 and the hole portion is opened when the valve body portion 37 separates from the valve seat portion 38.

[0039] Next, an explanation will be given of the structure for preventing the axial valve body 36 from coming off upward. The lower end portion of the axial valve body 36 in FIG. 1 is, as shown in FIG. 1, in a downward arrow shape or a triangular cross-sectional shape. The lower end portion is inserted into the inside of a cylindrical locking body 40 provided at the bottom of the liquid cylinder 19, contacts the inner peripheral surface of the locking body 40, and slides on the inner peripheral surface of the locking body 40 in that state. That is, the axial valve body 36 and the locking body 40 are in frictional contact, and the frictional force generated between the two restricts the relative movement of the two in the axial direction. Further, at the upper end portion of the locking body 40, there is a so-called hook shape that slightly protrudes toward the inner peripheral side, and the lower end portion of the axial valve body 36 having a triangular cross-section described above is caught by this portion. As a result, the upward movement of the axial valve body 36 is restricted by the locking body 40, that is, it is prevented from coming off. Therefore, the lower end portion of the axial valve body 36 becomes an engaging portion 41 with respect to the locking body 40, and the portion where the upper end portion of the locking body 40 protrudes toward the inner peripheral side becomes a hook portion 42. This locking body 40 corresponds to the holder member in the present invention.

[0040] Note that the locking body 40 is not a complete cylinder over its entire length in the axial direction, but a plurality of slits 43 along the axial direction are formed in the peripheral wall portion on the lower end side. This is for allowing the content sucked up into the locking body 40 to flow into the inside of the liquid cylinder 19. Further, a flange protruding radially outward is formed at the lower end portion of the locking body 40, and the lower end portion of the spring 35 constituting the above-described return mechanism abuts against this flange. That is, the reaction force for pushing up the liquid piston 31 acts on the locking body 40, and the locking body 40 is fixed to the lower end portion side of the liquid cylinder 19 by this reaction force.

[0041] At the bottom of the liquid cylinder 19, a check valve is provided which opens when sucking up the contents from the inside of the bottle 2 into the inside of the liquid chamber 34 and closes when extruding the contents from the liquid chamber 34. In the example shown in FIG. 1, the check valve is constituted by a ball valve 44. That is, at the bottom of the liquid cylinder 19, a funnel-shaped valve seat portion 45 with an inner diameter gradually decreasing downward is formed. The opening on the central side of this valve seat portion 45 corresponds to the suction port in the present invention, and a ball 46 is arranged so as to contact the tapered surface of the valve seat portion 45 from above. Further, at the bottom of the liquid cylinder 19, a tube 47 for introducing the contents filled inside the bottle 2 into the inside of the liquid chamber 34 is connected. The tip of the tube 47 extends to the vicinity of the bottom of the bottle 2 (not shown).

[0042] In the example shown in FIG. 1, the ball 46 corresponds to the abutting portion and the ball-shaped valve body in the present invention. In addition to the function of opening and closing the suction port, it has the function of pushing up the above-described shaft-shaped valve body 36 relative to the liquid piston 31, that is, the function as a downward movement preventing portion that abuts against the lower end portion of the shaft-shaped valve body 36 and prevents its downward movement. It is necessary to prevent the downward movement of the shaft-shaped valve body 36 when the shaft-shaped valve body 36 descends together with the descent of the liquid piston 31. The liquid piston 31 abuts against the upper end portion of the upper end portion of the liquid cylinder 19, that is, the bottom portion of the air cylinder 18 where it is folded upward, and the lower limit position is regulated, and this is the stroke end. Assuming that the distance, that is, the stroke amount, from the upper limit position shown in FIG. 1 to the lower limit position when the liquid piston 31 descends is S31, in order to push up the shaft-shaped valve body 36 that has descended together with the liquid piston 31 relative to the liquid piston 31, it is necessary to bring the shaft-shaped valve body 36 into contact with the ball 46 and prevent its downward movement before the liquid piston 31 reaches the lower limit position. Therefore, in the example shown in FIG. 1, assuming that the distance (stroke amount) from the upper limit position where the engaging portion 41 in the shaft-shaped valve body 36 engages with the hook portion 42 of the locking body 40 to the lower limit position (downward movement preventing position) where it abuts against the ball 46 is S36, the stroke amount S36 of the shaft-shaped valve body 36 is smaller than the stroke amount S31 of the liquid piston 31 (S36 > S31).

[0043] In the normal state where the shaft-shaped valve body 36 can move up and down independently of the liquid piston 31, when the nozzle portion 9 is pushed down, the upper end portion of the shaft-shaped valve body 36 engages with the protrusion 30 provided inside the cylindrical portion 29 described above and descends together with the nozzle portion 9. If the lower end portion of the shaft-shaped valve body 36 that descends in this way comes into contact with the ball 46, the pushing down of the nozzle portion 9 will be blocked, and therefore the descent of the liquid piston 31 will be blocked before it reaches its lower limit position. To avoid such a situation, the above-described respective stroke amounts S31 and S36 are S31 - C ≤ S36 set to this. Here, C is the clearance described above, and is the descent distance of the nozzle portion 9 and the liquid piston 31 until the protrusion 30 provided inside the cylindrical portion 29 described above comes into contact with the upper end portion of the shaft-shaped valve body 36.

[0044] In the pump former 1 according to the present invention described above, an upward pushing force by the spring 35 always acts on the liquid piston 31. On the other hand, the shaft-shaped valve body 36 disposed inside the liquid piston 31 has its upward movement restricted by the engagement portion 41 at its lower end being caught by the hook portion 42 of the locking body 40. Since the valve seat portion 38 formed at the upper end portion of the liquid piston 31 is pressed against the valve body portion 37 provided at the upper end portion of the shaft-shaped valve body 36, ultimately, the upward movement of the liquid piston 31 is restricted by the shaft-shaped valve body 36 and held at the upper limit position. In that state, the valve body portion 37 and the valve seat portion 38 are brought into close contact by the elastic force of the spring 35. Before the start of use of the product, that is, in the storage or storage state such as when the pump former 1 is attached to the bottle 2, since the valve body portion 37 and the valve seat portion 38 are placed in a closely contacted state over a long period of time, for example, when the environmental temperature is high, the valve body portion 37 may adhere to the valve seat portion 38.

[0045] When explaining the behavior when the valve body portion 37 and the valve seat portion 38 (the shaft-like valve body 36 and the liquid piston 31) are fixed at the start of the pump former 1, when the nozzle portion 9 is pushed down, the air piston 21 and the liquid piston 31 that are integrated with the nozzle portion 9 by fitting the cylindrical portion 29 into the inner cylinder portion 12 of the nozzle portion 9 descend. The shaft-like valve body 36 fixed to the liquid piston 31 also descends together with the liquid piston 31. FIG. 2 shows the state during the descent, and the on-off valve is closed because the valve body portion 37 is fixed to the valve seat portion 38. Further, the engaging portion 41 at the lower end of the shaft-like valve body 36 is disengaged downward from the hook portion 42 of the locking body 40. Furthermore, the ball 46 remains on the valve seat portion 45 of the suction port, and the suction port is closed. Therefore, when the liquid piston 31 is pushed down, the air in the liquid chamber 34 is compressed and the internal pressure increases. If the adhesive force fixing the valve body portion 37 to the valve seat portion 38 is greater than the force pushing up the shaft-like valve body 36 based on this internal pressure, the shaft-like valve body 36 remains fixed to the liquid piston 31 and further descends.

[0046] Since the stroke amount S31 to the lower limit position of the liquid piston 31 and the stroke amount S36 until the shaft-like valve body 36 abuts against the ball 46 are set in the above-described relationship, the lower end portion of the shaft-like valve body 36 abuts against the ball 46 (that is, the descent prevention portion) before the liquid piston 31 descends to the lower limit position. Therefore, when the liquid piston 31 is pushed down to the lower limit position, the shaft-like valve body 36 provided inside thereof is prevented from descending by the ball 46, and is pushed up relative to the liquid piston 31. The state is shown in FIG. 3. As a result, the valve body portion 37 is peeled off from the valve seat portion 38 and the on-off valve opens, and air escapes from the liquid cylinder 19.

[0047] Thereafter, when the pushing down of the nozzle portion 9 is released, the liquid piston 31 and the air piston 21 integrated therewith are pushed up by the spring 35. Along with this, the internal volume of the liquid piston 31 increases and the internal pressure decreases, so the ball valve 44 opens and the contents are sucked from the inside of the bottle 2 into the inside of the liquid cylinder 19.

[0048] Thus, after moving the nozzle portion 9 up and down once at the start of use and then pressing down the nozzle portion 9 again, since the fixation between the shaft-like valve body 36 and the liquid piston 31 has already been released, the liquid piston 31 and the air piston 21 descend, and the shaft-like valve body 36 remains at the upper limit position. That is, the valve mechanism (on-off valve) composed of the valve body portion 37 and the valve seat portion 38 opens, and the content is pushed out from the inside of the liquid cylinder 19 into the mixing chamber 32. Also, air inside the air chamber 24 is pressurized and supplied to the mixing chamber 32. As a result, the content and the pressurized air are mixed to form bubbles, and the bubbles are further refined by passing through the net held by the net holder 14, and then are discharged from the nozzle port 11. The state where the nozzle portion 9 is pushed down to the lower limit in this way is shown in FIG. 4.

[0049] Therefore, according to the pump former 1 which is the discharge device according to this invention shown in FIG. 1, when the nozzle portion 9 is pushed down at the start of use, although the content may not be discharged at the first time, the fixation between the shaft-like valve body 36 and the liquid piston 31 can be surely released by one push-down, and the content in the bottle 2 can be surely sucked into the liquid chamber 34. As a result, the content can be discharged from the nozzle port 11 by subsequent push-down operations, avoiding or suppressing so-called dry firing which is a wasteful push-down where the content is not discharged, and improving or enhancing the convenience of the discharge device or the product / commodity to which the pump former 1 is attached. Note that the operation of the pump former 1 during normal times after starting the use of the pump former 1 is the same as that described in the above-mentioned Japanese Patent No. 5435794, and thus a detailed description thereof is omitted.

[0050] The present invention is not limited to the above-described embodiments. In essence, the downward prevention part in the present invention is such that when the axial valve body 36 descends together with the liquid piston 31, before the liquid piston 31 reaches the lower limit position, it engages with the axial valve body 36 to prevent its descent and pushes the axial valve body 36 upward relative to the liquid piston 31. Therefore, the downward prevention part in the present invention is not limited to the aforementioned ball 46 or ball valve 44. As another example of the downward prevention part, FIG. 5 shows an example in which the locking body 40 and the protrusion 36A formed on the axial valve body 36 so as to abut against the upper end portion thereof are used as the downward prevention part. Specifically, at a predetermined position in the vertical direction of the axial valve body 36, a protrusion 36A protruding outward in the radial direction is formed. The protrusion 36A may be the lower end portion of a portion where the axial valve body 36 has a larger diameter, or a rib (not shown) formed along the axial direction on the outer peripheral surface of the axial valve body 36, and may also be the lower end portion of the rib. And the radius of the protrusion 36A measured from the center of the axial valve body 36 is larger than the inner diameter of the upper end opening of the cylindrical locking body 40. That is, the protrusion 36A is shaped to abut against the upper end portion of the locking body 40 from above. Therefore, in the example shown in FIG. 5, the protrusion 36A abutting against the upper end portion of the locking body 40 corresponds to the abutting part in the present invention.

[0051] In the configuration shown in FIG. 5, the distance (dimension) from the protrusion 36A on the axial valve body 36 at the upper limit position to the upper end portion of the locking body 40 is the stroke amount S36 of the axial valve body 36 described above. Therefore, the position of the protrusion 36A is determined so that the relationship between the stroke amount S36, the stroke amount S31 of the liquid piston 31, and the clearance C satisfies the above-described conditions. Therefore, even in the case of the configuration shown in FIG. 5, when the axial valve body 36 descends together with the liquid piston 31, before the liquid piston 31 descends to the lower limit position, the protrusion 36A abuts against the upper end portion of the locking body 40 to prevent its descent. As a result, the axial valve body 36 is pushed upward relative to the liquid piston 31, and the fixation of the axial valve body 36 to the liquid piston 31 can be released.

[0052] Moreover, since the present invention is not limited to a pump former, it may be a device that discharges a liquid or a highly viscous fluid or the like.

Explanation of Signs

[0053] 1 Pump former 2 Bottle 4 Cap 9 Nozzle part 11 Nozzle opening 15 Cylinder member 18 Air cylinder 19 Liquid cylinder 21 Air piston 31 Liquid piston 32 Mixing chamber 34 Liquid chamber 35 Spring 36 Axial valve body 36A Projection 37 Valve body part 38 Valve seat part 40 Locking body 41 Engaging part 42 Hook part 44 Ball valve 45 Valve seat part 46 Ball C Clearance S31,S36 Stroke amount

Claims

1. A cap attached to an upper opening of a container body for containing a content, a nozzle portion that is held vertically movably on the cap and has a discharge port for discharging the content, a piston that moves vertically together with the nozzle portion, a cylinder that closely fits with the piston, and the internal volume increases due to the relative upward movement of the piston to suck the content, and the internal volume decreases due to the relative downward movement of the piston to extrude the content, a shaft-like valve body inserted into a hole formed through the piston in the vertical direction and prevented from coming out upward, and provided at an upper end portion of the shaft-like valve body, closing the hole by closely fitting into the hole to define an upper limit position of the piston, and a valve portion that opens the hole when the piston moves relatively downward. In the pump-type discharge device having: The pump-type discharge device is characterized in that it has a downward movement prevention portion that engages with the shaft-like valve body to prevent the downward movement of the shaft-like valve body before the piston reaches a predetermined lower limit position when the shaft-like valve body descends in conjunction with the piston.

2. In the pump-type discharge device according to Claim 1, The pump-type discharge device is characterized in that the downward movement prevention portion is a butting portion provided inside the cylinder and butting against a lower end portion of the shaft-like valve body.

3. In the pump-type discharge device according to Claim 2, An inlet for sucking the content is formed at a lower end portion of the cylinder due to an increase in the internal volume of the cylinder, A ball-shaped valve body that closes the inlet from the inside of the cylinder is provided inside the cylinder so as to be vertically movable, The pump-type discharge device is characterized in that the butting portion is constituted by the ball-shaped valve body.

4. In the pump-type discharge device according to Claim 1, A holder member that inserts a lower portion of the shaft-like valve body therein and engages the shaft-like valve body upward to prevent it from coming out upward is provided inside the cylinder, The pump-type discharge device is characterized in that the downward movement prevention portion is constituted by a radially protruding portion provided on the shaft-like valve body so as to abut against the upper end portion of the holder member from above. ​

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