JP2024106464A - Pump type dispenser - Google Patents

Abstract

[Problem] A pump-type dispenser that is excellent in recyclability and can dispense contents in the same way as conventional ones is proposed. [Solution] The elastic member 5 of the pump-type dispenser 1 includes an upper annular portion 5a supported by the head 4, a lower annular portion 5b supported by the cap 2, and an elastically deformable peripheral wall portion 5c provided between the upper annular portion 5a and the lower annular portion 5b. When the elastic member 5 is interposed between the cap 2 and the head 4, the peripheral wall portion 5c includes an upper peripheral wall portion 5e connected to the lower end of the upper annular portion 5a and extending upward from the lower end, a folded peripheral wall portion 5f extending so as to be folded back against the upper peripheral wall portion 5e, and a lower peripheral wall portion 5g extending downward from the folded peripheral wall portion 5f and connected to the upper end of the lower annular portion 5b, and includes at least three vertical slits 5h that penetrate the peripheral wall portion 5c and are provided at intervals in the circumferential direction. [Selected Figure] Figure 1A

Description

The present invention relates to a pump-type dispenser.

A known pump-type dispenser includes a cap that is attached to the mouth of a container, a pump that is held at the mouth by the cap and is driven by the back and forth movement of a stem, and a head that is connected to the stem; the contents of the container are dispensed from the head's outlet by moving the head toward the cap (see, for example, Patent Document 1).

As shown in Patent Document 1, inside such a pump-type dispenser, a coil spring is provided to return the head, which has been moved toward the cap, to its initial position.

JP 2011-31950 A

However, while most of the components of this type of pump dispenser are made of synthetic resin, the coil spring is made of metal. For this reason, when it is discarded after use, it cannot be recycled as a resin product in this state. Furthermore, in general, in this type of pump dispenser, the components are firmly fixed to each other, for example by fitting, to prevent them from coming loose during normal use. Therefore, it takes time to disassemble the pump dispenser and separate the coil spring from the other components.

Here, the inventor of the present application has studied pump-type dispensers that do not use coil springs and developed the pump-type dispenser 101 shown in Figures 4A and 4B. The pump-type dispenser 101 is attached to a bottle-shaped container P for use. The container P has a cylindrical mouth P1 centered on the axis O and a male screw portion P2 provided on the outer circumferential surface of the mouth P1, and has a storage space S inside in which the contents are stored. The pump-type dispenser 101 is equipped with a cap 102 attached to the mouth P1, a pump 103 held at the mouth P1 by the cap 102 and driven by the back and forth movement of the stem 112, a head 104 having a discharge port 104d for discharging the contents to the outside and connected to the stem 112, and an elastic member 105 interposed between the cap 102 and the head 104 and biasing the head 104 in a direction away from the cap 102. The elastic member 105 is made of a relatively soft material such as rubber, elastomer, or soft polyethylene (low density polyethylene).

After further investigations using such a pump-type dispenser 101, it was found that when the head 104 was pressed down as shown in FIG. 5A, the pressed down head 104 sometimes did not return to its upward position.

In order to solve these problems, the present invention aims to propose a pump-type dispenser that is highly recyclable and can dispense the contents in the same way as conventional dispensers.

The present invention provides a pump-type dispenser comprising: a cap that is attached to the mouth of a container that contains contents; a pump that is held at the mouth by the cap and is driven by the back and forth movement of a stem; a head that has a discharge port for discharging the contents to the outside and is connected to the stem; and an elastic member that is interposed between the cap and the head and biases the head in a direction away from the cap, the head being moved toward the cap to dispense the contents in the container from the discharge port,
the elastic member includes an upper annular portion supported by the head, a lower annular portion supported by the cap, and an elastically deformable peripheral wall portion provided between the upper annular portion and the lower annular portion,
When the elastic member is interposed between the cap and the head, the peripheral wall portion comprises an upper peripheral wall portion connected to the lower end of the upper annular portion and extending upward from the lower end, a folded peripheral wall portion extending so as to be folded back onto the upper peripheral wall portion, and a lower peripheral wall portion extending downward from the folded peripheral wall portion and connected to the upper end of the lower annular portion, and is a pump-type dispenser having at least three vertical slits that penetrate the peripheral wall portions and are spaced apart circumferentially.

It is preferable that the vertical slit penetrates the folded peripheral wall portion and the lower peripheral wall portion.

It is preferable that there are four vertical slits.

When the working length when the head is moved from top dead center to bottom dead center along the axis of the mouth portion is L1, and the length along the axis from the bottom surface of the upper peripheral wall portion to the bottom surface of the vertical slit when the elastic member is not incorporated between the cap and the head is L2, it is preferable that the following formula (1) is satisfied.
0.80≦(L2/L1)≦0.97...(1)

The pump-type dispenser of the present invention, configured as described above, allows the depressed head to stably return to its upward position, as described below. In addition, since it does not use a metal coil spring as in the past, it can be recycled as a resin product without disassembly.

FIG. 1C is a cross-sectional view taken along line AA in FIG. 1B in a state where the head has risen to the top dead center, showing one embodiment of a pump-type dispenser according to the present invention. FIG. 1B is a plan view of the elastic member in the state shown in FIG. 1A. FIG. 1B is a half cross-sectional view of the elastic member shown in FIG. 1A in a state where it is not installed between the cap and the head. 3B is a cross-sectional view of the pump-type dispenser shown in FIG. 1A with the head pressed down (the head moved to the bottom dead center). FIG. FIG. 3B is a plan view of the elastic member in the state shown in FIG. 3A. FIG. 4C is a cross-sectional view taken along CC in FIG. 4B in a state where the head has risen to the top dead center in the pump-type discharge device initially considered. FIG. 4B is a plan view of the elastic member in the state shown in FIG. 4A. 5B is a cross-sectional view of the pump-type dispenser shown in FIG. 4A taken along line DD in FIG. 5B in a state in which the head is pressed down (a state in which the head has moved to the bottom dead center). FIG. 5B is a plan view of the elastic member in the state shown in FIG. 5A. 1B is a table showing the results of a study on the pump-type dispenser shown in FIG. 1A when the number of vertical slits is changed. 1B is a table showing the results of a study on the pump-type dispenser shown in FIG. 1A when the length of the vertical slit is changed.

One embodiment of the pump-type dispenser according to the present invention will be described below with reference to the drawings. In the following description, the up-down direction refers to the direction along the axis O shown in the drawings, and the side where the container P is located as shown in FIG. 1A will be described as "bottom" and the side where the head 4 is located as "top". The radial direction refers to the direction perpendicular to the axis O in a plane perpendicular to the axis O, and the circumferential direction refers to the direction rotating around the axis O in this plane. Note that in FIG. 3B and FIG. 5B, the deformation state of the elastic members 5, 105 is partially exaggerated.

First, in the pump-type dispenser 101 shown in Figures 4A and 4B, when the head 104 is pressed down as shown in Figure 5A, the problem that the pressed down head 104 does not return to the upward position will be described in detail.

After further investigation of the pump-type dispenser 101, the inventor found that the elastic member 105, which was elastically deformed by the depressed head 104, deformed to become a rectangle in plan view, as shown in FIG. 5B. Furthermore, it was discovered that in the areas corresponding to the four corners of the rectangle, the inner circumferential surfaces of the elastic members 105 come into contact with each other, as shown to the right of the axis O in FIG. 5A, and that the frictional resistance generated at these contacting areas prevents the head 104 from returning upward.

Based on these considerations, the inventor developed a pump-type dispenser 1 as shown in Figure 1A. The pump-type dispenser 1 of this embodiment is used by attaching it to a bottle-shaped container P. The container P has a cylindrical mouth portion P1 centered on an axis O, and a male thread portion P2 provided on the outer periphery of the mouth portion P1, and has a storage space S inside in which the contents are stored.

The pump-type dispenser 1 of this embodiment also includes a cap 2, a pump 3, a head 4, an elastic member 5, and a packing 13. The elastic member 5, the packing 13, and the piston 11 described below are made of relatively soft materials such as rubber, elastomer, and soft polyethylene (low density polyethylene), while the other members are made of relatively hard materials such as polypropylene, polybutylene terephthalate, and polyacetal.

The cap 2 has a cap body 2a that covers the outer periphery and upper end of the mouth P1. A female threaded portion 2b that corresponds to the male threaded portion P2 is provided on the inner periphery of the cap body 2a, and the cap 2 can be attached to the container P by screwing the male threaded portion P2 and the female threaded portion 2b together. The upper surface of the cap body 2a is provided with an annular wall portion 2c that is annular and holds the elastic member 5. In addition, on the upper surface of the cap body 2a, a concave wall portion 2d that is concave downward and holds the cylinder 6 (described later) is provided on the radially inner side of the annular wall portion 2c.

The pump 3 includes a cylinder 6, a tube 7, a poppet 8, a stopper 9, a piston guide 10, a piston 11, and a stem 12.

The cylinder 6 is generally cylindrical in shape, and at its bottom is a tapered section 6a that tapers downward. Below the tapered section 6a is a cylindrical tube holder 6b. At the top of the cylinder 6 is a hole (suction port 6c) that passes through the cylinder 6 in the radial direction.

The tube 7 is hollow, and its upper end is inserted into and held by the tube holding portion 6b. The lower end of the tube 7, not shown, is located near the bottom of the container P.

The poppet 8 is generally shaped like a rod, and at its vertically intermediate portion is provided a protrusion 8a that protrudes radially outward. The poppet 8 is disposed within the cylinder 6 and is movable along the axis O. When the poppet 8 moves downward as shown in FIG. 3A, its lower end portion seats over its entire circumference against the reduced diameter portion 6a. In other words, the poppet 8 functions as a check valve in cooperation with the cylinder 6.

The stopper 9 is annular and is inserted into the cylinder 6 and held by the cylinder 6 above the protrusion 8a. As shown in FIG. 1A, when the poppet 8 moves upward, the protrusion 8a engages with the stopper 9, preventing the poppet 8 from slipping out of the cylinder 6.

The piston guide 10 is generally cylindrical and is disposed inside the cylinder 6 above the poppet 8. The lower inner circumferential surface of the piston guide 10 is in sliding contact with the upper outer circumferential surface of the poppet 8. The piston guide 10 also has a hole (communication port 10a) that penetrates in the radial direction. In addition, the lower outer circumferential surface of the piston guide 10, which is located below the portion where the communication port 10a is located, has a larger diameter than the outer circumferential surface of the portion where the communication port 10a is located.

The piston 11 is generally annular and is disposed inside the cylinder 6 while being inserted into the piston guide 10. The piston 11 is movable vertically relative to the piston guide 10. The outer peripheral surface of the piston 11 is in sliding contact with the inner peripheral surface of the cylinder 6. When the piston 11 moves downward relative to the piston guide 10, the lower end portion of the piston 11 located on the radially inner side is seated over the entire circumference against the above-mentioned lower outer peripheral surface of the piston guide 10. In other words, the piston 11 functions as a check valve in cooperation with the piston guide 10.

The stem 12 is generally cylindrical and is held in place by the piston guide 10 inserted inside it.

The pump 3 constructed from these components is held in the cap 2 by assembling the components together as shown in FIG. 1A and then inserting the upper end of the cylinder 6 into the recessed wall portion 2d.

The head 4 is provided with a head body 4a having a shape with a disk-shaped top wall and a peripheral wall provided on the outer edge of the top wall. The head body 4a is provided with a stem holding portion 4b having a cylindrical shape and extending downward. The head 4 is held by the stem 12 by inserting the upper end of the stem 12 inside the stem holding portion 4b. The head 4 is also provided with a nozzle 4c that communicates with the inside of the stem holding portion 4b and extends radially outward. The tip of the nozzle 4c is provided with an outlet 4d for discharging the contents to the outside. The head body 4a is provided with ribs 4e spaced apart in the circumferential direction on the inside and located at a height where the lower end surface is aligned with the lower surface of the nozzle 4c.

The elastic member 5 has the shape shown in FIG. 2 when it is alone (when not installed between the cap 2 and the head 4), and when it is installed between the cap 2 and the head 4, it elastically deforms into the shape shown in FIG. 1A. As shown in FIG. 2, the elastic member 5 has an upper annular portion 5a that forms a ring shape, a lower annular portion 5b that forms a ring shape, an elastically deformable peripheral wall portion 5c that is provided between the upper annular portion 5a and the lower annular portion 5b, and an annular ring wall portion 5d that extends radially outward from the lower annular portion 5b.

As shown in FIG. 1A, when the elastic member 5 is inserted between the cap 2 and the head 4, the lower annular portion 5b is inserted into the inside of the annular wall portion 2c until the ring wall portion 5d contacts the upper surface of the annular wall portion 2c and is held therein. The upper annular portion 5a is located radially outside the stem holding portion 4b, and its upper end contacts the lower surface of the nozzle 4c and the lower surface of the rib 4e. In this state, the peripheral wall portion 5c is elastically deformed, and the head 4 is biased upward by the elastic member 5.

When the peripheral wall portion 5c is interposed between the cap 2 and the head 4 as shown in FIG. 1A, it comprises an upper peripheral wall portion 5e that is connected to the lower end of the upper annular portion 5a and extends upward from this lower end, a folded peripheral wall portion 5f that is curved in an arc and extends so as to be folded back on the upper peripheral wall portion 5e, and a lower peripheral wall portion 5g that extends downward from the folded peripheral wall portion 5f and connects to the upper end of the lower annular portion 5b.

The peripheral wall portion 5c also has vertical slits 5h that extend in the up-down direction and penetrate the peripheral wall portion 5c. In this embodiment, a total of four vertical slits 5h are provided at equal intervals in the circumferential direction as shown in FIG. 1B. In this embodiment, the vertical slits 5h penetrate from the portion of the folded peripheral wall portion 5f that connects to the upper peripheral wall portion 5e to a portion of the lower peripheral wall portion 5g that is located above the portion that connects to the lower annular portion 5b as shown in FIG. 1A.

The packing 13 is in the shape of a circular ring and is inserted into and held in the cylinder 6.

The pump-type dispenser 1 constructed from these components is attached to the container P by inserting the cylinder 6 into the inside of the mouth P1 and screwing the female threaded portion 2b into the male threaded portion P2, as shown in FIG. 1A. At this time, the packing 13 is sandwiched between the top surface of the mouth P1 and the upper inner surface of the cap body 2a, preventing problems such as the contents of the storage space S overflowing from the mouth P1 when the container P is turned over.

When the pump-type dispenser 1 is used to dispense the contents of the storage space S, the head 4 is pushed down as shown in FIG. 3A. In the following explanation, it is assumed that the contents of the storage space S have already been introduced into the cylinder 6.

When the head 4 moves downward, the stem 12 connected to the head 4 also moves downward, and the piston guide 10 and piston 11 move downward relative to the cylinder 6, with the poppet 8 seated at its lower end on the reduced diameter portion 6a. As the piston 11 moves downward, the contents in the cylinder 6 are pressurized, pass through the communication port 10a, pass through the inside of the piston guide 10 and stem 12, and then pass through the inside of the nozzle 4c and are discharged from the discharge port 4d. Note that the suction port 6c that was blocked by the piston 11 as shown in Figure 1A is opened as the piston 11 moves downward as shown in Figure 3A. Here, the space in the cylinder 6 that was partitioned by the piston 11 and whose volume increases as the piston 11 moves is depressurized. In other words, when the head 4 is pressed down and the piston 11 moves downward, the space above the piston 11 in the cylinder 6 is depressurized, but the pressure in this space does not decrease because the air in the storage space S can be introduced into the cylinder 6 through the suction port 6c that opens as the piston 11 moves downward. Therefore, the piston 11 is not affected by this decompression when it moves downward, and the piston 11 can move downward smoothly.

When the head 4 is pressed down, the elastic member 5 is elastically deformed as shown in FIG. 3A. The elastic member 5 has a vertical slit 5h, and when the head 4 is pressed down, the elastic member 5 is deformed so that the vertical slit 5h opens in the circumferential direction as shown in FIG. 3B. That is, in the pump-type dispenser 101 shown in FIG. 4A and FIG. 4B, when the head 104 is pressed down as shown in FIG. 5A, the elastically deformed elastic member 105 is deformed to become a rectangle in a plan view as shown in FIG. 5B. At the parts corresponding to the four corners of this rectangle, the inner circumferential surfaces of the elastic member 105 come into contact with each other, generating frictional resistance, which may prevent the head 4 from returning upward. However, the elastic member 5 with the vertical slit 5h can prevent such frictional resistance from occurring, and the head 4 can be returned upward smoothly.

When the head 4 moves upward due to the restoring force of the elastic member 5, the stem 12 connected to the head 4 also moves upward, and the piston guide 10 and the piston 11 move upward relative to the cylinder 6. At this time, the lower end of the piston 11 is seated on the lower outer circumferential surface of the piston guide 10 described above, so that the flow of the contents between the inside of the cylinder 6 and the communication port 10a is stopped. In other words, as the piston 11 moves upward relative to the cylinder 6, the space located below the piston 11 in the cylinder 6 is depressurized. Therefore, as shown in FIG. 3A, the poppet 8, whose lower end was seated against the reduced diameter portion 6a, rises, and the contents of the storage space S are introduced into the cylinder 6 via the tube 7.

In this way, the head 4 is pushed down and then returned to its original position by the elastic member 5, allowing the contents of the storage space S to be repeatedly ejected.

Here, we will explain what is the optimal vertical slit 5h in the elastic member 5. The elastic member 5 used in the following study is made of soft polyethylene (low density polyethylene).

First, the results of the study on the number of vertical slits 5h will be described with reference to FIG. 6. In any case, the vertical slits 5h are provided at equal intervals in the circumferential direction around the axis O of the elastic member 5. The load during setting in FIG. 6 is the elastic force when the elastic member 5 in the single state shown in FIG. 2 is assembled between the cap 2 and the head 4 as shown in FIG. 1A and urges the head 4 upward. The load during operation in FIG. 6 is the maximum value of the force applied to the head 4 when moving the head 4 from the top dead center shown in FIG. 1A to the bottom dead center shown in FIG. 3A. When the elastic member 5 in the single state shown in FIG. 2 is assembled between the cap 2 and the head 4 as shown in FIG. 1A, the elastic member 5 is elastically deformed by 4 mm in the length along the axis O. The operating length L1 when moving the head 4 from the top dead center to the bottom dead center along the axis O is 11.5 mm.

When there are zero vertical slits 5h (Comparative Example 1, the embodiment shown in FIG. 4A), the elastic member 5 deforms to become rectangular in plan view when the head 4 is pressed down, and the head 4 may not return to its upward position. Also, when there are two vertical slits 5h (Comparative Example 2), the pressed down head 4 may not return to its upward position. In Comparative Example 2, when the head 4 is pressed down, the elastic member 5 deforms to become angular in plan view at a point 90° circumferentially shifted from the vertical slits 5h, and at this angular point, the inner circumferential surfaces of the elastic members 5 come into contact with each other, generating frictional resistance that affects the return of the head 4.

On the other hand, when the number of vertical slits 5h was three, four, five, or six as in Examples 1 to 4, the head 4 returned well. When the number of vertical slits 5h was three, a tendency for a part of the pressed-down elastic member 5 to deform so as to form a corner in plan view was observed. When the number of vertical slits 5h was five or six, the phenomenon of the pressed-down elastic member 5 deforming so as to form a corner in plan view was not observed, but the restoring force of the elastic member 5 decreased as the number of vertical slits 5h increased, so the head 4 sometimes did not return completely to the top dead center. For this reason, it is more preferable to have four vertical slits 5h.

Next, the results of the study on the length of the vertical slits 5h will be explained with reference to FIG. 7. As shown in FIG. 1A and FIG. 1B, four vertical slits 5h are provided at equal intervals in the circumferential direction. Here, the length of the vertical slits 5h is defined as the length L2 along the axis O from the bottom surface of the upper peripheral wall portion 5e to the bottom surface of the vertical slits 5h, as shown in FIG. 2. After further studies using elastic members 5 with different lengths of the vertical slits 5h, it was found that the performance of the elastic member 5 to return the head 4, as shown in FIG. 7, differs depending on the value obtained by dividing the length L2 by the operating length L1 (11.5 mm in this embodiment) when moving the head 4 from the top dead center to the bottom dead center along the axis O.

In the case of Example 8 and Examples 9 to 11, the head 4 that was pressed down returned satisfactorily due to the elastic member 5. In the case of Example 12, the inner circumferential surfaces of the elastic members 5 sometimes came into slight contact with each other when the head 4 was pressed down, and in the cases of Examples 13 to 17, the inner circumferential surfaces of the elastic members 5 sometimes came into contact with each other when the head 4 was pressed down. In the cases of Examples 5 to 7, the restoring force of the elastic members 5 was reduced, and the head 4 sometimes did not return completely to the top dead center. Based on the results of this study, it can be said that it is preferable to set the vertical slit 5h in the range of 0.80≦(L2/L1)≦0.97.

Although one embodiment of the present invention has been described above, the present invention is not limited to the specific embodiment, and various modifications and changes are possible within the scope of the spirit of the present invention described in the claims unless otherwise specifically limited in the above description. For example, the configuration of the above-mentioned embodiment can be added or deleted as appropriate, and the configuration of one embodiment can be applied to other embodiments. Furthermore, the effects of the above-mentioned embodiment are merely examples of the effects resulting from the present invention, and do not mean that the effects of the present invention are limited to the above-mentioned effects.

For example, the pump is not limited to being made of the above-mentioned components, and pumps with other configurations may be used.

1: Pump-type discharger 2: Cap 2a: Cap body 2b: Female threaded portion 2c: Annular wall portion 2d: Concave wall portion 3: Pump 4: Head 4a: Head body 4b: Stem holding portion 4c: Nozzle 4d: Discharge port 4e: Rib 5: Elastic member 5a: Upper annular portion 5b: Lower annular portion 5c: Circumferential wall portion 5d: Ring wall portion 5e: Upper peripheral wall portion 5f: Folded-back peripheral wall portion 5g: Lower peripheral wall portion 5h: Vertical slit 6: Cylinder -6a: Reduced diameter portion 6b: Tube holding portion 6c: Suction port 7: Tube 8: Poppet 8a: Protrusion 9: Stopper 10: Piston guide 10a: Communication port 11: Piston 12: Stem 13: Packing 101: Pump type discharger 102: Cap 103: Pump 104: Head 104d: Discharge port 105: Elastic member 112: Stem O: Axis P: Container P1: Mouth portion P2: Male thread portion S: Storage space

Claims (4)

a pump-type dispenser comprising: a cap that is attached to the mouth of a container that contains contents; a pump that is held at the mouth by the cap and is driven by the back and forth movement of a stem; a head that has a discharge port for discharging the contents to the outside and is connected to the stem; and an elastic member that is interposed between the cap and the head and biases the head in a direction away from the cap, the head being moved toward the cap to discharge the contents in the container from the discharge port,
the elastic member includes an upper annular portion supported by the head, a lower annular portion supported by the cap, and an elastically deformable peripheral wall portion provided between the upper annular portion and the lower annular portion,
When the elastic member is interposed between the cap and the head, the peripheral wall portion comprises an upper peripheral wall portion connected to the lower end of the upper annular portion and extending upward from the lower end, a folded peripheral wall portion extending so as to be folded back onto the upper peripheral wall portion, and a lower peripheral wall portion extending downward from the folded peripheral wall portion and connected to the upper end of the lower annular portion, and the pump-type dispenser is provided with at least three vertical slits that penetrate the peripheral wall portion and are spaced circumferentially. The pump-type dispenser according to claim 1, wherein the vertical slit penetrates the folded peripheral wall portion and the lower peripheral wall portion. The pump-type dispenser according to claim 1, wherein the number of vertical slits is four. 4. The pump-type dispenser according to claim 3, wherein the following formula (1) is satisfied, where L1 is an operating length when the head is moved from top dead center to bottom dead center along the axis of the mouth portion, and L2 is a length along the axis from the bottom surface of the upper peripheral wall portion to the bottom surface of the vertical slit in a state in which the elastic member is not incorporated between the cap and the head:
0.80≦(L2/L1)≦0.97...(1)

Images