JPH08198302A - Liquid spray pump - Google Patents

Abstract

PURPOSE: To obtain an excellent liquid spray pump which has no dripping of liquid and can prevent liquid from drying out to solid. CONSTITUTION: A liquid spray pump is equipped with an annular piston 23 and an auxiliary piston 24. The annular piston 23 is slidably fitted in a cylinder 3 and its lower part is fitted in and connected to a stem 22, allowing liquid to flow through. The auxiliary piston 24 is fitted on the lower part of the stem 22 so that the auxiliary piston 24 can move up and down within a specified range, and slidably fitted in the annular piston 23 so that it can open and close a through-hole 31 provided in the circumferential wall of the stem 22. When a head 26 is pushed down to open the through-hole 31, liquid in the cylinder 3 is introduced into the stem 22 through the through-hole 31 and sprayed from a nozzle 25 via a spray valve 27. When the head 26 is moved up, the liquid in the nozzle 25 flows back into the stem 22 and the liquid in a container is sucked up into the cylinder 3 through a suction valve 9. The auxiliary piston 24 can block the through-hole 31 only when the stem 22 is at the uppermost position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a liquid jet pump,
More specifically, the present invention relates to a liquid jet pump used to discharge a viscous liquid.

[0002]

2. Description of the Related Art As a liquid jet pump, as shown in FIG. 12, a mounting cap fitted to the mouth and neck 101 of a container body 100.
102, a cylinder 104 that is fixed to the container body by the cap, and has a suction valve 103 provided in a lower end portion that hangs down into the container body, and a central portion of the cylinder that is vertically movable with upward biasing, A discharge valve in which a valve hole provided in the upper part of the inside is closed by a valve body 105 that moves up and down by hydraulic pressure.
A stem 107 having a closed lower end surface, which is provided with 106, is fitted to the outer peripheral lower end portion of the stem so as to be vertically movable within a predetermined width, and the outer peripheral edge is slidably fitted to the inner surface of the cylinder. It is known that an annular piston 109 having a through hole 108 formed in the opening is provided so as to be openable and closable, and a push-down head 111 with a nozzle 110 provided continuously with the upper end of the stem so as to be vertically movable above the mounting cap. Has been.

By pressing down the push-down head, the annular piston moves up relative to the stem to open the through hole, and the pressurized liquid in the cylinder is introduced into the stem through the opened through hole. , Is ejected from the nozzle via the discharge valve. On the other hand, when the push-down head is raised, the annular piston is relatively lowered to close the through hole, and the negative pressure in the cylinder causes the liquid in the container body to be sucked up into the cylinder through the suction valve.

The suction valve 10 of the conventional pump of this type
3 and the discharge valve 106 are generally composed of valve seats 112 and 113 and ball-shaped valve bodies 114 and 105 mounted on the respective valve seats. Further, the ball-shaped valve element rises by hydraulic pressure when the valve is opened, but the ball-shaped valve body is raised by a locking rib 115 in the cylinder as shown in FIG. 12 and a bar-shaped projection 116 hung vertically from the back surface of the top wall of the push-down head. It is configured to lock the valve body. These vertical movement widths are slightly different depending on the size of the container and the like, but are generally set to a minimum clearance of about 1 to 4 mm that allows the liquid to flow.

Further, in general, the nozzle extends horizontally forward from the front surface of the head, and its tip is inclined and descends downward.

[0006]

In these conventional pumps, the ball-shaped valve element 10 of the discharge valve 106 is erroneously tilted when the container is in use.
Even if 5 is displaced from the valve seat 113, the annular piston 1
09 blocks the through-hole 108, allowing the inside of the cylinder 104 and the stem 107 to
This is an excellent one that can prevent leakage of liquid from the nozzle 110 as much as possible because the inside is blocked.

However, in the conventional pump of this type, there may be a problem that the liquid remaining in the nozzle drips from the tip after the liquid is jetted, and the liquid remaining at the tip of the nozzle is dried and solidified. May occur. This drying and solidification is not preferable not only in terms of appearance but also in the case of impeding the operation of ejecting the liquid, which is not preferable.

The present invention relates to an improvement of such a conventional pump, and proposes an excellent liquid jet pump which is free from liquid dripping and which can prevent the liquid from being dried and solidified as much as possible.

Another object of the present invention is to provide a pump having advantages that it can be manufactured easily by changing the structure of a very small part of the conventional product and can be manufactured at low cost.

Further, in the above-mentioned type of pump, there is a case that the piston does not move upward and the through hole is not opened when the pump is used for the first time.

That is, when the head is moved up and down for the first time after it is mounted on the container, air is naturally contained in the cylinder,
Therefore, initially, the air pressure causes the piston to rise. However, since air has elasticity compared to liquid, there is a case in which the piston does not move up even if the head is pushed down by the frictional force of the piston. Such inconvenience can be solved by moving the head up and down many times, but it is not preferable because it may be mistaken by the consumer as a defective product.

One of the objects of the present invention is, in addition to the above objects,
A pump which does not have such inconvenience is proposed.

[0013]

In order to solve the above-mentioned problems, the pump according to the first aspect of the present invention has a mounting cap 2 to be fitted into the neck of the container body, and the cap which is fixed to the container body and is inserted into the container body. A cylinder 3 in which a suction valve 9 is provided in a lower end portion to hang down, and a valve body in which a central portion of the cylinder is vertically movable with an upward biasing state and a valve hole provided in an upper portion of the inside is vertically moved by hydraulic pressure. The outer peripheral surface is slidably fitted to the inner surface of the cylinder 3 and the stem 22 provided with the discharge valve 27 closed by 39, and the lower inner peripheral surface is connected to the lower outer surface of the stem 22 so that liquid can flow. A through hole formed by fitting the annular piston 23 in the lower part of the outer periphery of the stem so as to be vertically movable with a predetermined width, slidably fitting the outer peripheral surface of the inner surface of the annular piston, and drilling in the peripheral wall of the stem. 31 can be opened and closed An annular auxiliary piston 24 and a push-down head 26 with a nozzle 25 that is continuously provided on the upper end of the stem and is provided so as to be vertically movable above the mounting cap are provided, and through a through hole 31 opened by pushing down the push-down head. The liquid in the cylinder is introduced into the stem and is ejected from the nozzle 25 via the discharge valve 27. When the push-down head 26 rises, the liquid inside the container is sucked through the valve 9 by the negative pressure in the cylinder. The liquid ejecting pump is configured to suck up into the inside, and is configured as a liquid ejecting pump characterized in that the through hole 31 can be closed by the auxiliary piston 24 only at the stem highest position.

Further, in the pump of the second aspect of the invention, the volume in the nozzle 25 is Va, the volume in the flow passage of the vertically movable portion of the discharge valve body 39 is Vb, and the volume of the discharge valve body 39 is Vc. The liquid jet pump according to claim 1, wherein the vertical movement width of the discharge valve body 39 is regulated so that Vb-Vc is equal to or larger than Va.

A pump according to a third aspect of the invention is configured as the liquid jet pump according to the first aspect, in which the suction valve member 17 constituting the suction valve 9 is constantly urged in the valve closing direction.

Further, in the pump of the fourth aspect of the present invention, the auxiliary piston 24 is always urged upward with respect to the stem 22, and the through hole 31 can be closed by the auxiliary piston 24 only when the stem 22 is at the highest position. The liquid jet pump according to claim 1 is constructed.

Further, in the pump of the fifth aspect of the invention, the auxiliary piston 24 can be locked to the cylinder 3 in the closed state of the through hole 31 at the highest position of the stem 22, and the head 26 of the head 26 can be locked. The liquid jet pump according to claim 1, wherein the lock is released after the through hole 31 is opened by pushing down.

[0018]

Function: Used by being attached to the container body 5 containing a viscous liquid. For example, when the screwing portion of the vertical movement member 4 is removed from the state of FIG. 1 and the head 26 is raised, the upper surface of the auxiliary piston 24 is finally locked to the lower surface of the inner cylinder 15a, and only the stem 22 moves upward, so that the auxiliary The bottom surface of the piston 24 is the upward step of the stem.
32 Ascend until close to the top surface. At this time, the auxiliary piston
24 descends relative to the stem 22, and the stem 22 stops with the through hole 31 closed (see FIG. 3).

When the head 26 is pushed down from this state, hydraulic pressure causes the auxiliary piston 24 to rise relatively to the stem 22 and the through hole 31.
Is opened and the liquid in the cylinder 3 is opened.
After passing through 31, the discharge valve 27 is opened from the stem 22 and jetted out through the nozzle 25. At this time, the discharge valve body 39 is hydraulically pushed up to the lower surface of the locking plate 41 (see FIG. 4).

Next, when the head 26 is released, the vertical movement member 4 rises due to the elastic force of the coil spring 20, and the negative pressure in the cylinder 3 causes the discharge valve element 39 to move relative to the vertical movement member 4. To descend and close the valve. By the time the discharge valve 27 is closed, the liquid in the stem 22 flows back into the cylinder 3 through the through hole 31, and the liquid in the flow path in which the discharge valve body 39 moves up and down along with it is the stem upstream of the discharge valve. The liquid flows back into the nozzle 22, and the liquid in the nozzle 25 flows backward into the flow path. During this time, the suction valve 9 does not open. When the discharge valve 27 is closed, the suction valve 9 is opened and the liquid in the container body is introduced into the cylinder 3, and the vertical movement member 4 is introduced until it reaches the highest position (see FIG. 5).

At the most raised position of the stem 22, the through hole 31 is closed and the state shown in FIG. 3 is restored.

In the embodiment shown in FIGS. 6 to 9, the suction valve member 17 is constantly urged in the valve closing direction by the coil spring 42 so that the operation of opening the suction valve 9 after the discharge valve 27 is closed is made more reliable. ing.

Further, the auxiliary piston 24 is always urged upward with respect to the stem 22 to always surely open the through hole 31, and the elastic force of the coil spring 43 for that purpose is
If the upper surface of the auxiliary piston 24 is locked to the lower surface of the inner cylinder 15a when the stem 22 is raised to the maximum, the auxiliary piston 24 upper surface is locked by making it smaller than the elastic force of the coil spring 20 that biases the stem upward. 24 descends relative to the stem 22 and the through hole 31
To block. Further, when the head 26 is pushed down from this state, the auxiliary piston 24 rises with respect to the stem 22 by the elastic force of the coil spring 43, and immediately and surely opens the through hole 31.

Other functions are similar to those of the embodiment shown in FIG.

In the embodiment shown in FIGS. 10 and 11, when the vertically moving member 4 is raised, the locking projection 44 of the auxiliary piston 24 is provided.
While overcoming and engaging with the locking projection 46 of the inner cylinder, the upper surface of the auxiliary piston 24 is abutted and locked by the downward step portion 45, while
The lower surface of the auxiliary piston 24 comes into close contact with the upper surface of the upward step 32 of the stem to close the through hole 31.

When the head 26 is pushed down from this state, the auxiliary piston 24 is stopped by the mutual engagement of the respective locking ridges 44 and 46, the through hole 31 is surely opened, and then the downward step of the stem.
33 locks and pushes down the upper surface of the auxiliary piston, and disengages the locking projections.

The other operations are similar to those of the embodiment shown in FIG.

[0028]

Embodiments of the present invention will be described below with reference to the drawings.

1 to 5 show an embodiment of the present invention, in which 1 denotes a liquid jet pump. The pump 1 is
The mounting cap 2, the cylinder 3, and the vertical movement member 4 are provided.

The mounting cap 2 includes the cylinder 3 and the container body 5.
The peripheral wall 7 is screwed onto the outer periphery of the neck portion 6 of the container body, and the top wall 8 in the form of an inward flange extends from the upper edge of the peripheral wall 7.

The cylinder 3 is fixed to the container body 5 by the mounting cap 2, the lower end portion is suspended in the container body, and the suction valve 9 is provided at the inner lower end portion.

In this embodiment, the cylinder 3 is provided with a flange 11 projecting outward from the outer peripheral upper portion of the cylindrical peripheral wall 10 and a bottom wall 12
A flange-shaped valve seat 13 is provided so as to incline inward and downward from a peripheral edge portion of a window opening at the center, and a fitting cylinder portion 14 is provided so as to protrude downward from the peripheral edge of the bottom surface of the bottom wall 12. An upper end of a suction pipe (not shown) is fitted to the fitting cylinder portion 14, and a lower portion of the suction pipe (not shown) is hung on a lower end portion of the container body.

A locking member 15 for locking the vertically movable member 4 in a depressed state is fitted and fixed to the upper end of the peripheral wall 10. The engaging member 15 has a fitting tubular portion fitted on the outer circumference of the upper end of the cylinder 3 via a concave-convex engaging means, and extends vertically from a donut plate-shaped top plate. It is configured by vertically arranging an inner cylinder 15a fitted to. Inner cylinder
The 15a and the inner surface of the upper end of the cylinder 3 are prevented from rotating by mutual engagement of vertical ridges, and a screw thread is provided around the inner circumference of the inner cylinder 15a for screwing the vertical moving member. .

Then, a packing 16 is provided on the upper surface of the neck 6 of the container body.
The outwardly facing flange 11 is placed via the above, and the flange 11 is sandwiched between the top wall 8 of the mounting cap 2 screwed onto the outer periphery of the mouth and neck and the upper surface of the mouth neck 6 of the container body.

The suction valve 9 is constructed by providing a suction valve member which comes into close contact with the lower surface of the valve seat 13 and closes the valve hole at the inner peripheral edge of the valve seat 13 so as to be vertically movable within a predetermined width.

In the present embodiment, the suction valve member 17 is formed in a cylindrical shape with its lower peripheral edge being in close contact with the upper surface of the valve seat 13 and having a cylindrical lower end. Further, the member 17 has a plurality of circumferentially rectangular locking plate-like locking projections 18 projecting from the lower end of the outer circumference thereof, while the cylinder 3
The lower end surface of the coil spring 20 for urging the up-and-down moving member 4 upward is locked to the upper surface of the rectangular plate-shaped plate rib 19 circumferentially protruding from the lower end of the inner peripheral wall 10 of each of the above-mentioned locking projections. 18
Is movable up and down until it contacts the lower surface of the coil spring 20. Reference numeral 21 in the drawing denotes a plurality of ribs provided in the circumferential upper part on the outer peripheral upper part of the suction valve member 17.

The vertical moving member 4 includes a stem 22, an annular piston 23, an auxiliary piston 24, a push-down head 26 with a nozzle 25, and the like.

The stem 22 is provided so that the central portion of the cylinder 3 can be moved up and down while being urged upward, and the valve hole provided in the upper portion of the inside of the stem 22 is closed by a valve body that moves up and down by hydraulic pressure.
Is formed into a cylindrical shape with a closed lower end surface.

In this embodiment, a cylindrical shape is formed with the lower end surface closed, and a flange 28 is provided so as to project outward from the outer peripheral lower end portion, and a gap is formed from the outer peripheral edge of the flange 28 to the inner surface of the cylinder. A hanging wall 29 is provided vertically.

The annular piston 23 has an outer peripheral surface fitted to the inner surface of the cylinder 3 so as to be liquid-tight and slidable, and a lower inner peripheral surface is integrally connected to a lower outer surface of the stem 22 so that liquid can flow. It is installed so that it can move integrally with the stem.

In this embodiment, an upward skirt-shaped upper sliding portion 23b and a downward skirt-shaped lower sliding portion 23c are provided so as to project from the outer circumference of the cylindrical base portion 23a, and each sliding portion is surrounded by the inner circumference of the cylinder. Liquid-tightly and slidably press-fitted to the surface, and a plurality of connecting rods 30 standing up obliquely outward and upward from the outer peripheral edge of the upper surface of the flange 28 of the stem 22 are erected in the circumferential direction, and the respective tip ends thereof are respectively erected. It is integrally connected to the lower part of the inner surface of the base portion 23a of the annular piston 23.

The auxiliary piston 24 is fitted to the lower part of the outer periphery of the stem 22 so as to be vertically movable within a predetermined width, and the outer periphery of the auxiliary piston 24 is slidably fitted to the inner surface of the annular piston 23. The through hole 31 is provided so that it can be opened and closed.

In this embodiment, an inner skirt-shaped inner sliding portion 24b protruding from the upper end of the inner peripheral portion of the cylindrical base portion 24a is fitted to the outer peripheral surface of the stem 22 in a liquid-tight and slidable manner, and the base portion 24a. A downward skirt-shaped outer sliding portion 24c protruding from the lower portion of the outer periphery is fitted in a liquid-tight and slidable manner on the inner peripheral surface of the base portion 23a of the annular piston 23. Also, the base 24a
A cylindrical valve piece 24d is provided so as to extend downward from the lower portion of the inner circumference, and a locking tubular portion 24e having an inverted L-shaped cross section is provided so as to project from the upper portion of the outer circumference of the base portion.

On the other hand, an upward step portion 32 is provided around a predetermined lower portion of the outer periphery of the stem 22, and a downward step portion is provided at a predetermined position above the step portion 32.
33, and the lower surface of the cylindrical valve piece 24d is the upward step 32
It is provided so as to be vertically movable from a state in which it closely contacts the upper surface to a state in which the inner sliding portion 24b abuts on the lower surface of the downward stepped portion 33.

The upward step 32 and the downward step 33 are also provided.
A through hole 31 is formed below the peripheral wall of the stem.

When the vertical movement member 4 is pushed down from the raised position, the auxiliary piston 24 relatively rises with respect to the stem 22 by hydraulic pressure (air pressure when a pump having no liquid in the cylinder is used for the first time). Through hole 31 opens, while
When the vertical movement member 4 rises, the lower end edge of the inner cylinder 15a abuts and locks the upper surface of the locking cylinder portion 24e of the auxiliary piston 24, and the stem 22 still rises to cause the lower surface of the cylindrical valve body 24 to rise. Is closely contacted with the upward step 32 and the through hole 31 is closed.

At this time, the auxiliary piston 24 also serves to block the through hole 34 provided in the cylinder 3 for introducing the outside air. The through hole 34 is provided in the upper part of the peripheral wall of the cylinder, and when the up-and-down moving member 4 rises, the outside air is introduced between the stem 22 and the inner cylinder 15a through the through hole 34 into the negatively pressured container body. When the stem 22 is introduced and is at the highest position, the upper end edge of the locking cylinder portion 24e of the auxiliary piston 24 is in airtight contact with the lower end edge of the inner cylinder 15a to shut off the inside and outside of the container. .

The push-down head 26 is continuously provided on the upper end of the stem 22 and is provided so as to be vertically movable above the mounting cap 2. In the present embodiment, the push-down head 26 is a cylindrical casing having a lower end surface opening in which a peripheral wall is vertically provided from a peripheral edge of the top wall.
The vertical end of the vertical pipe 36 is provided vertically from the center of the lower surface of the top wall of the casing 35.
It is fixed to. Further, a horizontal cylinder 37 having a base end portion opened on the front surface of the upper portion of the vertical cylinder 36 penetrates the peripheral wall of the casing and projects to the front thereof, thereby forming the horizontal cylinder 37 as the nozzle 25. The nozzle 25 is configured such that the base end portion is inclined and raised forward, and the tip end is inclined and lowered downward. With such a configuration, it is possible to further prevent dripping.

Further, a screw thread is provided around the outer periphery of the vertical cylinder 36 of the portion projecting downward from the casing 35, and when the vertical moving member 4 is pushed down, the screw thread is engaged with the screw thread of the locking member 15 to move up and down. The movable member 4 is configured so that it can be locked while being pushed down. At that time, the outer surface of the hanging wall 29 protruding from the stem 22 is liquid-tightly fitted to the inner surface of the reduced diameter portion provided in the lower portion of the cylinder peripheral wall, and the lower end of the outer periphery of the vertical cylinder 36 is inside the locking member 15. It is configured to be liquid-tightly fitted to the inner circumference of the downward skirt-shaped annular projection 38 provided on the inner surface of the cylinder 15a, and further, the lower end of the stem 22 is brought into contact with the upper surface of the suction valve member 17.

The discharge valve 27 is provided with a valve body 39 that closes a valve hole provided in the upper part of the stem 22 and is movable up and down by hydraulic pressure.

In this embodiment, a valve hole 40 is formed in the center of the stem 22 by projecting a flange-shaped valve seat 40 that inclines and descends inward, and a ball-shaped valve body is formed on the valve seat 40. The discharge valve 27 is configured by placing 39 to close the valve hole. Further, the valve body 39 is configured to be vertically movable up to a position where it abuts on the lower surface of the locking plate 41 which is vertically provided from the top wall of the casing 35.

The pump of the present invention is used for jetting a highly viscous liquid, and they are, for example, 500 cps to 15 cps.
A material having a viscosity of about 000 cps is used. When using such a highly viscous liquid, the discharge valve body 39 pushed up by the liquid pressure is unlikely to immediately drop onto the valve seat 40 due to its own weight, and the viscosity of the liquid, the weight of the valve body, etc. It moves up and down along the flow of the liquid, though it is slightly different. Therefore, no significant error occurs between the liquid flow rate and the valve body moving speed.

Further, in the present embodiment, the volume inside the nozzle 25 is Va, the volume inside the liquid flow path of the vertically movable portion of the discharge valve body 39 is Vb, and the volume of the discharge valve body 39 is Vc. Time,
The vertical movement width of the discharge valve body 39 is regulated so that Vb-Vc becomes equal to or larger than Va. The actual vertical movement width of the discharge valve body 39 due to this regulation depends on the length and inner diameter of the nozzle, the inner diameter of the stem 22, etc., but is about 5 mm to 30 mm, and the ball valve is placed on the valve seat. Larger than conventional valves. Particularly preferably, a width of 10 mm or more is desirable.

After the vertical movement member 4 is pushed down and the liquid is poured out, when the vertical movement member 4 rises, the liquid in the stem 22 flows back through the through hole 31 into the cylinder 3 which is made negative pressure. The liquid in the flow path in which the discharge valve body 39 moves up and down flows back into the stem 22 upstream of the discharge valve 27, and the liquid in the nozzle 25 flows back into the flow path. At this time, Vb-Vc is Va
Since it is the same as or larger than that, the liquid in the nozzle is configured to flow back into the substantially vertical cylinder.

6 to 9 show another embodiment of the present invention. In this embodiment, the suction valve member 17 is constantly urged in the valve hole closing direction by an elastic member.

In this embodiment, the horizontal spiral portion at the upper end is fitted and fixed between the upper surface of each plate rib 19 and the lower surface of the coil spring 20 in the above-described embodiment, and extends from the inner peripheral edge of the horizontal spiral portion. A coil spring 42 is provided as an elastic member in which the provided cylindrical portion is hung downward along the inner surface of each plate rib 19 and the lower surface thereof is locked to the upper surface of each locking projection 18 of the suction valve member 17. ing.

Further, in this embodiment, the auxiliary piston 24 is always biased upward with respect to the stem 22. A coil spring 43 is provided by engaging the upper end portion on the lower surface of the base portion 24a of the auxiliary piston 24 and the lower end portion between the connecting rods 30 and the outer surface of the stem. This spring 43
Is a coil spring 20 that biases the stem 22 upward.
The elastic force is weaker than that of, and when the stem 22 rises and the upper surface of the locking cylinder portion 24e of the auxiliary piston 24 is locked to the lower surface of the inner cylinder 15a, the stem 22 further moves up and the auxiliary piston twenty four
The lower surface of the cylindrical valve piece 24d rises until it comes into close contact with the upper surface of the upward step portion 32, so that the through hole 31 is closed only at the most raised position of the stem 22.

The other structure is similar to that of the embodiment shown in FIG.

10 and 11 show still another embodiment of the present invention. In this embodiment, the auxiliary piston 24 with respect to the cylinder 3 is in the closed state of the through hole 31 at the stem highest position. It is configured such that it can be locked and unlocked after the through hole 31 is opened by pushing down the head 26.

In this embodiment, in the embodiment shown in FIG. 1, the locking cylinder is formed in a cylindrical shape instead of an inverted L-shape in cross section.
A locking projection 44 is provided around the upper end of the outer periphery of the locking member 15. On the other hand, a step portion 45 facing downward is provided at a predetermined position on the lower end of the inner circumference of the inner cylinder 15a of the locking member 15.
And a locking projection 46 that engages with the locking projection 44 is provided below the step 45, and when the stem 22 rises, the locking tubular portion 24e is provided on the lower surface of the step 45. The upper surface is abutted and locked, and the engaging protrusions 44 and 46 are engaged with each other, and the stem 22
And the lower end of the tubular valve piece 24d abuts the upper surface of the upward step portion 32, so that the through hole 31 is closed. Further, when the head is pushed down from that state, the auxiliary piston 24 is surely locked to the inner cylinder 15a by the mutual engagement of the locking projections, so that the through hole 31 is surely opened and then the stem is opened. The upper surface of the inner sliding portion 24b is locked by the downward stepped portion 33 of the inner sliding portion 24b to disengage the engaging ridges from each other, and the auxiliary piston 24 descends together with the stem 22.

Further, in this embodiment, a plurality of spring pieces 47 are integrally projected from the lower surface of the stem, and the screw of the vertical moving member 4 is screwed into the screw of the inner cylinder 15a to move the vertical moving member 4. When locked to the cylinder in the depressed state, each spring piece
The suction valve member 17 is configured to come into pressure contact with the upper surface of the top wall of the suction valve member 17. With this configuration, the suction valve member
It is configured so that the suction valve can be reliably closed by pressing 17 down securely.

Each of the above-mentioned members is formed by appropriately selecting and using a synthetic resin, a metal, particularly an elastomer having elasticity.

[0063]

As described above, the pump of the present invention has an annular piston in which the outer peripheral surface is slidably fitted to the inner surface of the cylinder and the lower inner peripheral surface is connected to the lower outer surface of the stem so that liquid can flow. Auxiliary piston fitted to the lower part of the outer circumference of the stem so that it can move up and down with a predetermined width, slidably fitted to the inner surface of the annular piston, and capable of opening and closing a through hole formed in the peripheral wall of the stem. The liquid inside the cylinder is introduced into the stem through the through hole opened by pushing down the push-down head, and is ejected from the nozzle through the discharge valve. When the head rises, the negative pressure in the cylinder causes negative pressure inside the container. The liquid is sucked up into the cylinder through the suction valve, and the through-hole can be closed by the auxiliary piston only at the highest stem position. When the pump of the present invention is used for discharging the liquid, the liquid in the stem is passed through the through hole until the discharge valve is closed, when the head is lifted after the liquid is ejected by pushing down the pressing head. The liquid in the flow path in which the discharge valve body moves up and down flows back into the stem, and the liquid in the nozzle also flows back into the flow path.
The liquid dripping from the tip of the nozzle can be eliminated, and the liquid can be prevented from drying and solidifying as much as possible.

Since the annular piston that slides on the inner circumference of the cylinder and the auxiliary piston that opens and closes the through hole are provided, the annular piston that also serves as a guide for the vertical movement of the stem can be made thick and thick. As a result, the stem can be moved up and down in a stable manner, and the durability is also improved.

Further, since it can be manufactured by changing the structure of a very small part of the conventional product, it has an advantage that it can be manufactured easily and at low cost.

Further, even if the container is accidentally tilted at the time of use, the auxiliary piston closes the through hole at the stem highest position so that the leakage of the liquid from the tip of the nozzle can be prevented as much as possible. Further, in the pump of the second aspect of the invention, when the volume in the nozzle is Va, the volume in the flow path of the portion of the discharge valve body that can move up and down is Vb, and the volume of the discharge valve body is Vc, Vb
Since the vertical movement width of the discharge valve body is regulated so that −Vc is equal to or larger than Va, almost the entire amount of the liquid in the nozzle flows backward into the flow path in which the discharge valve body moves up and down, and a more reliable liquid is obtained. Prevents dripping and prevents liquid from drying and solidifying.

Further, in the pump of the third aspect of the invention, it is possible to reliably prevent the suction valve from opening until the discharge valve is closed,
As a result, the backflow of a predetermined amount of the liquid in the stem can be performed more reliably, and the liquid dripping and the drying and solidification of the liquid can be prevented more reliably.

Further, in the pumps of claims 4 and 5, when the head is pushed down and the auxiliary piston is pneumatically attached to the stem when air is still present in the cylinder when it is first mounted on the container body. Therefore, the inconvenience of not rising relatively can be reliably solved.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is an explanatory diagram of a push-down head portion of the embodiment.

FIG. 3 is an explanatory cross-sectional view of the same embodiment at the most raised position of the head.

FIG. 4 is an explanatory cross-sectional view when the head of the embodiment is pushed down.

FIG. 5 is an explanatory cross-sectional view when the head of the embodiment is lifted.

FIG. 6 is a sectional view showing another embodiment of the present invention.

FIG. 7 is an explanatory cross-sectional view of the same embodiment at the most raised position of the head.

FIG. 8 is an explanatory cross-sectional view when the head of the embodiment is pushed down.

FIG. 9 is an explanatory cross-sectional view when the head of the embodiment is lifted.

FIG. 10 is a sectional view showing still another embodiment of the present invention.

FIG. 11 is an explanatory cross-sectional view of the same embodiment at the most raised position of the head.

FIG. 12 is a sectional view showing an example of a conventional pump.

[Explanation of symbols]

2 ... Mounting cap, 3 ... Cylinder, 9 ... Suction valve, 17
… Suction valve member, 22… Stem, 23… Annular piston, 24
… Auxiliary piston, 25… Nozzle, 26… Depressing head, 27
… Discharge valve, 31… Through hole, 39… Discharge valve body

Claims (5)

[Claims] 1. A mounting cap 2 which is fitted to the neck of the container body, and which is fixed to the container body by the cap,
The cylinder 3 is provided with a suction valve 9 in the lower end portion that hangs down in the container body, and the central portion in the cylinder is provided so as to be able to move up and down while being upwardly biased, and the valve hole provided in the upper portion of the inside is moved by hydraulic pressure. The outer peripheral surface is slidably fitted to the inner surface of the cylinder 3 and the stem 22 provided with the discharge valve 27 closed by the valve body 39, and the lower portion of the outer surface of the stem 22 allows the liquid to flow through the lower inner surface. And a ring-shaped piston 23 connected to the stem, the stem is fitted to the lower part of the outer periphery of the stem so as to be vertically movable, the outer peripheral surface is slidably fitted to the inner surface of the ring-shaped piston, and the stem peripheral wall portion is bored. A ring-shaped auxiliary piston 24 having a through hole 31 that can be opened and closed, and a nozzle that is provided continuously to the upper end of the stem so as to be vertically movable above the mounting cap.
And a push-down head 26 with a 25, the liquid in the cylinder is introduced into the stem through the through hole 31 opened by pushing down the push-down head, and the liquid is ejected from the nozzle 25 through the discharge valve 27, and the push-down head is depressed. A liquid jet pump configured to suck up the liquid in the container body into the cylinder through the suction valve 9 by raising the negative pressure in the cylinder when 26 is raised, and the through-hole formed by the auxiliary piston 24 only at the stem highest position. A liquid jet pump characterized in that it is capable of closing 31. 2. When the volume inside the nozzle 25 is Va, the volume inside the flow passage of the vertically movable portion of the discharge valve body 39 is Vb, and the volume of the discharge valve body 39 is Vc, Vb-Vc is The liquid jet pump according to claim 1, wherein the vertical movement width of the discharge valve body 39 is regulated so as to be equal to or larger than Va. 3. The liquid jet pump according to claim 1, wherein the suction valve member 17 constituting the suction valve 9 is always biased in the valve closing direction. 4. The structure according to claim 1, wherein the auxiliary piston 24 is always urged upward with respect to the stem 22, and the through hole 31 can be closed by the auxiliary piston 24 only when the stem 22 is maximally raised. Liquid jet pump. 5. The auxiliary piston 24 is engageable with the cylinder 3 in the closed state of the through hole 31 at the highest position of the stem 22, and is engaged after the opening of the through hole 31 by pushing down the head 26. The liquid ejection pump according to claim 1, wherein the liquid ejection pump is configured so that the stop can be released.