Pump and ejection container using same

Abstract

To prevent a phenomenon that a spring comes off to be disassembled in an assembling process so as to perform manufacturing with a high yield despite having a structure in which the spring is arranged outside a piston and a cylinder.SOLUTION: A cylindrical piston bushing 21 connected to an upper end of a piston and a cylindrical cylinder bushing 31 connected to an opening of a cylinder are configured to overlap each other at least partially in a vertical direction. An upper end of the piston bushing 21 and a lower end of the cylinder bushing 31 are provided with an engaging part that prevents the cylinder bushing from separating from the piston bushing.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a pump that is attached to the opening of a container and ejects liquid from the container, and in particular to a pump having a structure in which the spring that constitutes the pump does not come into contact with the contents. [Background technology]

[0002] Pumps that are attached to the opening of a container and spray the liquid inside the container are generally made of resin for most of their components, but metal materials are used for ball valves and springs due to quality and manufacturing costs. Depending on the components of the liquid to be sprayed, the liquid may react with metal parts and change in quality. In such cases, it is necessary to change the components of the liquid to ones that do not react with metal parts, which causes inconvenience to the manufacturer.

[0003] Patent Document 1 proposes a pump designed to avoid placing metal parts in the liquid passage. This pump is a medicine dispenser, and is usually placed inside a cylinder, with a spring for pushing up the piston being placed outside the cylinder and the piston. In addition, in this medicine dispenser, in order to prevent external dust, foreign matter, and bacteria from entering the inside during the medicine ejection process, the upper end of the piston is made of a separate member from the lower part of the piston, and a second spring is placed between the upper end and lower part of the piston. As a result, when the medicine is not being ejected from the ejection port, the second spring pushes up the upper end member of the piston, blocking the ejection port. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2014-193338 A Summary of the Invention [Problem to be solved by the invention]

[0005] In a typical pump with a spring placed inside a cylinder, the spring is surrounded by the inner wall of the cylinder, so it can only move up and down, and no external forces other than those in the up and down direction are applied to the spring during manufacturing. Therefore, there is almost no chance of the spring coming off the cylinder during the pump assembly process during manufacturing.

[0006] On the other hand, in a pump in which a spring is disposed outside the cylinder and piston as in Patent Document 1, the spring cannot directly push up the bottom surface of the piston, so the spring is disposed between a protrusion of a member connected to the piston and a protrusion of a member connected to the cylinder. As is clear from Figure 2 of Patent Document 1, there is no tube to guide the periphery of the spring. Also, the length of the spring is longer than in a pump in which the spring is disposed inside the cylinder.

[0007] According to experiments by the inventors, in the pump having the structure of Patent Document 1, the member connected to the piston and supporting the upper end of the spring is connected to the piston only at one point, the upper end of the piston, and therefore is prone to wobbling with respect to the piston during the assembly process of the pump. If the connection between the member connected to the piston and the piston becomes wobble, the upper end of the spring will come off the protrusion of the member connected to the piston. In addition, if another member comes into contact with the spring from the outside during the assembly process, an external force other than that in the vertical direction will be applied to the spring, causing it to come off, and there is a problem that the spring and other parts will easily come apart.

[0008] An object of the present invention is to provide a pump that has a structure in which a spring is disposed outside the piston and cylinder, yet prevents the spring from coming loose and disassembling during the assembly process, and can be manufactured with a high yield. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, the pump of the present invention has a cylinder, a piston whose lower end is inserted into an opening of the cylinder, a cylindrical piston bushing connected to the upper end of the piston, a cylindrical cylinder bushing connected to the opening of the cylinder, and a spring that urges the piston upward relative to the cylinder.

[0010] The piston bush has an upper flange on its outer periphery for supporting the upper end of the spring. The cylinder bush has a lower flange on its outer periphery for supporting the lower end of the spring. The spring is sandwiched between the upper flange of the piston bush and the lower flange of the cylinder bush.

[0011] The piston bush and the cylinder bush are configured to at least partially overlap in the vertical direction. An engagement portion is provided at the upper end of the piston bush and the lower end of the cylinder bush to prevent the piston bush from separating from the cylinder bush while allowing the piston bush to move up and down in response to the up and down movement of the piston. Effect of the Invention

[0012] According to the present invention, since the upper end of the piston bush and the lower end of the cylinder bush engage with each other at the engagement portion, it is possible to prevent the piston bush from separating from the cylinder bush. As a result, even though the spring is disposed outside the piston and cylinder, it is possible to prevent the spring from coming off during the assembly process, thereby improving manufacturing efficiency. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a cross-sectional view of a jetting container 1 according to an embodiment of the present invention. [Diagram 2] FIG. 2 is an enlarged cross-sectional view of an upper portion of the ejection container 1 of the embodiment. [Diagram 3](a) A cross-sectional view of the nozzle returning to its original position after being pressed down when starting to use the spray container 1 of the embodiment, as the contents are filling the fixed quantity space; (b) A cross-sectional view of the pump nozzle being pressed down to spray the contents; (c) A cross-sectional view of the nozzle returning to its original position after spraying, as the contents are filling the fixed quantity space. [Figure 4] FIG. 2 is a perspective view of a pump 2 of the jetting container according to the embodiment. [Diagram 5] 2A is a perspective view of a piston bush of a pump 2 according to an embodiment, and FIG. 2B is a perspective view of a cylinder bush of the pump 2 according to the embodiment. [Figure 6] 5(a) to 5(d) are cross-sectional views showing the assembly process of the pump 2 of the jetting container according to the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, a jetting container 1 equipped with a pump according to an embodiment of the present invention will be described.

[0015] FIG. 1 is a cross-sectional view of the entire spray container 1, and FIG. 2 is an enlarged cross-sectional view of the upper part of the spray container 1. FIG. 3(a) is a cross-sectional view of the nozzle returning to its original position after it is pressed down when the spray container 1 is first used, while the content is being filled into the fixed-volume space, FIG. 3(b) is a cross-sectional view of the nozzle of the pump being pressed down to spray the content, and FIG. 3(c) is a cross-sectional view of the nozzle returning to its original position after spraying, while the content is being filled into the fixed-volume space. FIG. 4 is a perspective view of the pump. FIG. 5(a) is a perspective view of the piston bush, and FIG. 5(b) is a perspective view of the cylinder bush. FIG. 6 is a diagram for explaining the assembly process of the piston.

[0016] The ejection container 1 of this embodiment is, for example, a nasal ejection container for injecting a fixed amount of medicine into the nose.

[0017] As shown in FIG. 1, the ejection container 1 is configured to include a container 10 having a neck-shaped portion around an opening 11, a pump 2 for ejecting the contents of the container 10, and a fastener 3 for fixing the pump 2 to the neck-shaped portion of the container 10.

[0018] As shown in FIG. 2, the pump 2 includes a cylinder 30, a piston 20 having a lower end inserted into an opening of the cylinder 30, and a spring 40 that biases the piston 20 in a direction to push it up.

[0019] The piston 20 is composed of a piston core 20a, a piston valve 20b, a piston outer cylinder 20c, and a piston valve opening spring 20d. The piston valve 20b is arranged to cover the periphery of the lower end of the piston core 20a. The piston outer cylinder 20c is arranged to cover the periphery from the upper end of the piston valve 20b to the upper end of the piston core 20a, and is fixed to the piston core 20a. A piston outer cylinder flange 20e is provided on the outer periphery of the piston outer cylinder 20c. The piston valve opening spring 20d is arranged so that its upper end contacts the piston outer cylinder flange 20e and its lower end contacts the piston valve 20b, and urges the piston valve 20b downward, pressing the piston valve 20b against the piston core 20a.

[0020] The spring constant of the piston valve opening spring 20d is designed to be smaller than the spring constant of the spring 40. As a result, when the spring 40 presses down on the piston 20, the piston valve opening spring 20d is compressed by the pressure of the fixed quantity space 30a, opening the piston valve 20b.

[0021] A minute gap 20f is provided between the outer peripheral surface of the piston core 20a and the piston outer cylinder 20c, and this gap 20f serves as a flow path for guiding the content of the container 10 from the fixed quantity space 30a of the cylinder 30 to the nozzle 22.

[0022] The upper end of the piston outer cylinder 20c is fitted with the inner wall of a cylindrical piston bush 21. This connects the piston outer cylinder 20c and the piston bush 21.

[0023] An upper flange portion 21a is provided on the outer periphery of the piston bush 21. The lower portion of the piston bush 21 is cylindrical and covers the upper portion of the piston outer cylinder 20c.

[0024] On the other hand, the cylinder 30 has a peripheral portion 30b around the opening, and this peripheral portion 30b is configured to be mounted on the edge of the opening of the container 10.

[0025] A through hole 30c is provided at the lower end of the cylinder 30, and the through hole 30c is covered by a blade-shaped check valve 30d. A tube 12 for sucking up the contents of the container 10 is inserted into the through hole 30c. The cylinder 30 sucks up the contents of the container 10 through the tube 12 from the through hole 30c to the fixed amount space 30a inside.

[0026] A cylindrical cylinder bush 31 is inserted into the opening at the top of the cylinder 30 and is connected to the cylinder 30. The cylinder bush 31 has a lower flange 31a on its outer periphery. The lower flange 31a is supported by a peripheral edge 30b of the cylinder 30.

[0027] The spring 40 is disposed so as to be sandwiched between an upper flange portion 21a provided on the piston bush 21 and a lower flange portion 31a provided on the cylinder bush 31. As a result, the spring 40 biases the piston bush 21 and the piston 20 connected to the piston bush 21 in a direction to push the entire piston 20 upward relative to the cylinder bush 31 and the cylinder 30.

[0028] The lower cylindrical portion of the piston bushing 21 and the upper cylindrical portion of the cylinder bushing 31 are configured to at least partially overlap in the vertical direction. Here, as an example, the diameter of the upper cylindrical portion of the cylinder bushing 31 is configured to be smaller than the diameter of the lower cylindrical portion of the piston bushing 21. Therefore, the lower cylindrical portion of the piston bushing 21 can move up and down so as to cover the upper cylindrical portion of the cylinder bushing 31 as the piston 20 moves up and down, as shown in Figures 2, 3(a) and (b).

[0029] An engagement portion 50 is provided at the lower end of the piston bush 21 and the upper end of the cylinder bush 31. This engagement portion 50 allows the piston bush 21 to move up and down in association with the up and down movement of the piston 20, while preventing the cylinder bush from separating from the piston bush.

[0030] Specifically, an annular protrusion 31b is provided along the circumferential direction on the outer periphery of the upper end of the cylinder bush 31. Meanwhile, a convex portion 21b is provided on the inner periphery of the lower end of the piston bush 21. The convex portion 21b of the piston bush 21 engages with the annular protrusion 31b to prevent the piston bush 21 from moving away from the cylinder bush 31 in the vertical direction.

[0031] The shapes of the cylinder bush 31 and the piston bush 21 will be described in more detail below.

[0032] As shown in FIG. 5(a), the protrusions 21b of the piston bush 21 are provided at several locations along the circumferential direction.

[0033] On the other hand, as shown in Fig. 5(b), one or more slits 31c are provided in the cylinder bush 31 so as to cut out the upper end of the cylindrical portion. In the example of Fig. 5(b), the slits 31c are provided at two positions in the circumferential direction at equal intervals (every 180 degrees).

[0034] In this way, by providing the slit 31c at the upper end of the cylindrical part of the cylinder bush 31, the edge of the upper end of the cylinder bush 31 can bend inward when a force is applied from the outside in the radial direction. In the assembly process of the pump 2, when the lower end of the piston bush 21 is placed over the upper end of the cylinder bush 31, the convex part 21b at the lower end of the piston bush 21 needs to go over the annular protrusion 31b of the cylinder bush 31. However, since the upper end of the cylinder bush 31 is bent inward by being pushed by the convex part 21b, the convex part 21b can go over the annular protrusion 31b without crushing it. After the convex part 21b of the piston bush 21 goes over the annular protrusion 31b of the cylinder bush 31, the bending of the upper end of the cylinder bush 31 returns to its original state. The convex part 21b engages with the annular protrusion 31b while allowing the piston bush 21 to move up and down, and the structure is such that the piston bush 21 is not separated from the cylinder bush 31.

[0035] In this case, by providing slits 31c in the cylinder bush 31 and adopting a structure in which the convex portion 21b overcomes the annular protrusion 31b while bending the cylinder bush 31 radially inward during assembly, it is not necessary to reduce the amount of protrusion of the convex portion 21b and the annular protrusion 31b in order to overcome it. Therefore, it is possible to ensure the amount of protrusion of the convex portion 21b necessary to prevent the piston bush 21 from separating from the cylinder bush 31 after assembly, and to ensure the strength of engagement.

[0036] In addition, the piston bushing 21 has an inner wall at its upper part connected to the upper end of the piston outer cylinder 20c, and a protruding portion 21b at its lower end connected to the cylinder bushing 31 so as to be movable up and down, so that it is supported at two points, the top and bottom, and is less likely to wobble. This makes it possible to stabilize the positional relationship between the piston bushing 21 and the cylinder bushing 31 during assembly. Therefore, the spring 40 can be stably held between the upper flange portion 21a provided on the piston bushing 21 and the lower flange portion 31a provided on the cylinder bushing, and the spring 40 is less likely to come off.

[0037] A cylindrical ejection nozzle 22 is connected to the upper end of the piston bush. The tip of the ejection nozzle 22 is narrowed to form an ejection port 26. This nozzle 22 is, for example, a nasal drop nozzle, and is configured to guide the contents straight upward and eject them upward from the upper ejection port 26. A rod 24 is inserted into the ejection nozzle 22 to narrow the internal space.

[0038] The nozzle 22 is provided on its outer periphery with a nozzle flange 22a that allows the user to press down on the piston.

[0039] In addition, since the spring 40 is disposed outside the piston bush 21 and the cylinder bush 31, it does not come into contact with the contents such as medicine that are guided from the fixed amount space 30a of the cylinder 30 through the gap 20f of the piston 20 to the nozzle 22.

[0040] The pump 2 is fixed to the opening of the container 10 by a fixing device 3. In the example of Fig. 2, the fixing device 3 is screwed into a screw thread provided in a neck portion around the opening of the container 10, thereby fixing the cylinder 30 to the opening of the container 10 via a packing 60.

[0041] The fixture 3 has a cylindrical portion 3a that covers the outer periphery of the spring 40. Therefore, after the pump 2 is fixed to the container 10 by the fixture 3, the outer periphery of the spring 40 is covered by the cylindrical portion 3a of the fixture 3 and is not exposed to the outside.

[0042] The material of the cylinder bush 31 is preferably an elastic material to allow the edge of the upper end to bend due to the provision of the slits 31c. For example, a resin such as polypropylene or polyethylene can be used. Also, since the cylinder bush 31 does not directly contact the contents of the container 10, the cylinder bush 31 can be made of a metal that can bend.

[0043] <Pump 2 assembly process> Next, the assembly process of the pump 2 of this embodiment will be described with reference to FIG.

[0044] (Step in Figure 6(a)) First, the piston 20 is assembled. Specifically, the piston valve 20b is attached around the lower end of the piston core 20a, and the piston valve opening spring 20d is sandwiched between the piston outer cylinder flange 20e and the piston valve 20b, and then inserted into the piston outer cylinder 20c.

[0045] (Step in Figure 6(b)) Next, the cylinder 30 is assembled. Specifically, a packing 60 is attached under the peripheral portion 30b of the cylinder 30. A check valve 30d is attached to the bottom surface inside the cylinder 30, and the through hole 30c is covered by the check valve 30d.

[0046] (Step in Figure 6(c)) The piston 20 is inserted from the opening of the cylinder 30, the cylinder bush 31 is placed over the piston 20, and the cylinder bush 31 is inserted into the opening of the cylinder 30 to connect them. (Step in Figure 6(d)) The upper end of the spring 40 is attached to the upper flange 21a of the piston bush 21, and the spring 40 is placed over the piston 20 assembled in the step of FIG. 6(c). As a result, the upper inner wall of the piston bush 21 is connected to the upper end of the piston outer cylinder 20c, and the protrusion 21b at the lower end of the piston bush 21 is caused to ride over the annular protrusion 31b at the upper end of the cylinder bush 31 and engage with it. At this time, since one or more slits 31c are provided at the upper end of the cylinder bush 31, the upper end of the cylinder bush 31 can bend inward, and the protrusion 21b can ride over the annular protrusion 31b relatively easily. Therefore, the annular protrusion 31b is not crushed by the protrusion 21b of the piston bush 21, and after riding over it once, the height of the protrusion 21b and the height of the annular protrusion 31b are sufficient to prevent the engagement from being released.

[0047] In this manner, as the inner wall of the piston bushing 21 connects to the upper end of the piston outer cylinder 20c and the lower end engages with the cylinder bushing 31, the spring 40 is sandwiched and held between the upper flange portion 21a of the piston bushing 21 and the lower flange portion 31a provided on the cylinder bushing 31 (Figure 6(d)).

[0048] After this, the assembly of Figure 6 (d) is mounted so that the gasket 60 rests on the edge of the opening of the container 10, the fastener 3 is placed over the piston bush, and the fastener 3 is screwed into the threads around the opening of the container 10 to secure it in place.

[0049] Finally, the nozzle with the rod 24 inserted therein is fitted and connected to the upper end of the piston bush 21.

[0050] 6(d), the spring 40 is exposed to the outside, and therefore when the fixing device 3 comes into contact with the spring 40 when the fixing device 3 is being fitted, an external force is applied to the spring 40. However, in the configuration of this embodiment, the cylinder bush 31 and the piston bush 21 which sandwich and fix the spring 40 are engaged with each other at the annular projection 31b and the convex portion 21b, and therefore even if an external force is applied to the spring which biases the cylinder bush 31 and the piston bush 21 in a direction separating them, the cylinder bush 31 and the piston bush 21 will not separate and will not come apart.

[0051] In addition, by forming the slit 31c in the cylinder bush 31, even if the height of the annular protrusion 31b of the convex portion 21b is designed to be high enough to obtain sufficient engagement force, it is possible to prevent the force required for the convex portion 21b to overcome the annular protrusion 31b from becoming too large.

[0052] In this manner, according to this embodiment, the cylinder bushing 31 and the piston bushing 21 can be easily assembled, and further, the phenomenon in which the cylinder bushing 31 and the piston bushing 21 are separated due to the elastic force of the spring 40 or external forces, etc., can be prevented, thereby improving manufacturing efficiency.

[0053] <Operation of each part during ejection> Here, the operation of each part of the jetting container 1 of this embodiment when in use will be described with reference to FIGS. 3(a) to (c).

[0054] When a user presses down the nozzle flange 22a of the nozzle 22 at the start of using the ejection container 1, the piston 20 connected to the nozzle 22 is pressed down while compressing the spring 40. As a result, the lower end of the piston 20 compresses the fixed quantity space 30a in the cylinder 30.

[0055] After that, when the user releases the nozzle flange 22a, as shown in Fig. 3(a), the spring 40 expands and returns to its original position, causing the piston 20 to rise and reducing the pressure in the fixed-volume space 30a of the cylinder 30. As a result, the content of the container 10 passes through the tube 12, the through hole 30c, and the check valve 30d in this order, filling the fixed-volume space 30a in the cylinder 30. The check valve 30d prevents the content in the fixed-volume space 30a from returning to the container 10.

[0056] When the user presses the nozzle flange 22a again as shown in FIG. 3(b), the piston 20 is pressed down in the direction of compressing the spring 40, compressing the metered volume 30a filled with the contents, and the pressure in the metered volume 30a rises. When this pressure becomes greater than the spring force of the piston valve opening spring 20d pressing down the piston valve 20b, the pressure presses the piston valve opening spring 20d and pushes up the piston valve 20b. As a result, a gap is created between the piston valve 20b and the piston core 20a, and the contents of the metered volume space 30a in the cylinder 30 rise through the gap between the piston valve 20b and the piston core 20a, and further through the gap 20f between the piston core 20a and the piston outer cylinder 20c, reach the upper end of the piston bush 21, and enter the nozzle 22. The contents are then ejected from the ejection port 26 through a flow path between the inner wall of the nozzle 22 and the rod 24.

[0057] When the user releases the nozzle flange 22a, as shown in Fig. 3(c), the spring 40 expands and returns to its original position, causing the piston 20 to rise and reducing the pressure in the fixed-volume space 30a of the cylinder 30. As a result, the content of the container 10 passes through the tube 12, the through-hole 30c, and the check valve 30d in this order, filling the fixed-volume space 30a in the cylinder 30.

[0058] Thereafter, each time the user presses down on nozzle flange portion 22a, the processes in FIGS. 3(b) and 3(c) are repeated, allowing the contents to be ejected. [Explanation of symbols]

[0059] 1 squirt container 2. Pump 3 Fixtures 3a Cylindrical part 10 containers 11 Aperture 12 tubes 20 Piston 20a piston core 20b Piston valve 20c Piston outer cylinder 20d Piston valve opening spring 20e Piston outer cylinder flange 20f gap 21 Piston bush 21a Upper flange 21b Convex part 22 Nozzle 22a Nozzle flange 24 Rod 26 spout 30 Cylinder 30a quantitative space 30b Periphery 30c through hole 30d Check valve 31 Cylinder bush 31a Lower flange 31b Annular protrusion 31c Slit 40 Spring 50 Engagement part 60 Packing

Claims

1. a cylinder, a piston having a lower end inserted into an opening of the cylinder, a cylindrical piston bush connected to an upper end of the piston, a cylindrical cylinder bush connected to the opening of the cylinder, and a spring that urges the piston upward relative to the cylinder, the piston bushing has an upper flange on its outer periphery for supporting an upper end of the spring; the cylinder bushing has a lower flange on its outer periphery for supporting a lower end of the spring; the spring is disposed so as to be sandwiched between the upper flange portion of the piston bush and the lower flange portion of the cylinder bush, a pump comprising: the piston bush and the cylinder bush configured to at least partially overlap in the vertical direction; and an engagement portion provided at a lower end of the piston bush and an upper end of the cylinder bush for preventing the piston bush from separating from the cylinder bush while allowing the piston bush to move up and down in association with the up and down movement of the piston.

2. 2. The pump according to claim 1, wherein a diameter of the cylinder bush at an overlapping portion of the piston bush is smaller than a diameter of the piston bush, a piston bushing having a lower end and a protrusion formed on an inner periphery thereof, the protrusion engaging with the annular protrusion to prevent the cylinder bushing from separating from the piston bushing.

3. 3. The pump according to claim 2, wherein the upper end of the cylinder bush is provided with one or more slits.

4. 4. The pump according to claim 3, wherein the number of the slits is multiple and the slits are provided at equal intervals in the circumferential direction of the cylinder bush.

5. 5. The pump according to claim 1, wherein a jet nozzle is connected to an upper end of said piston bush.

6. The present invention includes a container having an opening, a pump for ejecting the contents of the container, and a fixture for fixing the pump to the opening of the container, 6. A spray container, comprising: a pump according to claim 1.

7. 7. The spray container according to claim 6, wherein the fixing device has a cylindrical portion that covers an outer periphery of the spring.

Images