JPH04266761A - Liquid drop generation device - Google Patents

Abstract

PURPOSE:To prevent a change in delivery amount due to liquid level fluctuation, easily cope with trouble such as delivery failure due to bubble intake or the like, and always realize intended aromatic environment in a cassette type aroma generation device used as a built-in component of a compact air conditioning equipment. CONSTITUTION:An aromatic liquid storage container is divided into upper and lower sections, and a liquid drop delivery head 5 is provided on the bottom of a lower container 21 having such a structure as watering space for a bird. A nozzle 4 having a surface applied with a oil repellent coat is so provided as to undergo only static pressure corresponding to the height of a liquid level in the lower container 21. Also, a bubble removal passage 11 is provided on top of a pressure chamber 9 and normally closed with a spherical closing member 12. When an air bubble is sucked, the aforesaid closing member 12 is moved by an externally fitted electromagnet, thereby eliminating the air bubble. According to this construction, a less expensive and highly reliable aroma generation device can be embodied.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a droplet generating device, especially a scent generating device, which can be incorporated into an air conditioner or air conditioner, such as an air conditioner, to optimally control the scent environment in a car, a residence, or an office space. It is related to.

0002

2. Description of the Related Art An example of a conventional fragrance generating device for an air conditioner is the structure disclosed in Japanese Patent Application Laid-Open No. 1-127828. Furthermore, as a method for ejecting minute droplets, a piezo-driven ink droplet ejecting device used in a drop-on-demand type inkjet head and the like is known.

[0003] The conventional technology will be briefly explained below with reference to the drawings. FIG. 10 shows the configuration of a conventional scent generating device, which includes a cylinder 200 filled with a plurality of scents, and an electrically operated device installed in the middle of a pipe 400 connected to the cylinder 200 by a control circuit 300. The spray amount control valve 500 is opened and closed to control the type and amount of the desired fragrance from the fragrance spray port 600.

Next, FIG. 11 shows an example of a piezo-driven ink droplet ejection head, in which a piezo plate 14 is bonded to a diaphragm 13.
When the electric signal 3 is input to both sides of the piezo plate 14 and the diaphragm 13 are displaced, a sudden pressure rise is caused in the ink 30 in the pressure chamber 9, and the nozzle 4 provided in a part of the pressure chamber 9 is
This is to eject minute ink droplets from the ink droplet.

[0005]

SUMMARY OF THE INVENTION The above-mentioned conventional scent generating device targets an office building, is quite large-scale device, and is rather intended for centralized scent management. For this reason, the device is large and expensive, and it also has the problem of not being able to accommodate the preferences of each individual.

[0006]Also, a conventional ink droplet ejection head using a piezo vibrator can be used as a scent ejection device;
If air bubbles are inhaled, it becomes impossible to expel them, so it is necessary to equip the device with a complicated mechanism or means to remove the air bubbles, resulting in an increase in costs. Furthermore, when removing air bubbles, the aromatic liquid in the pressure chamber must be discharged to the outside together with the air bubbles, but there is a problem that leakage of fragrance from the expelled aromatic liquid obstructs the intended aroma environment. There is also the problem that if the meniscus is not sufficiently formed near the nozzle, unnecessary liquid drips will occur.

[0007] The present invention solves the above-mentioned problems and is an inexpensive device that can be incorporated into heating and cooling equipment manufactured to be installed in each room in a car, a general home, or an office, and can create a scented environment that suits each person's taste. The purpose is to provide a highly reliable scent generator.

[0008]

[Means for Solving the Problems] In order to solve the above problems, the fragrance generating device of the present invention includes an upper aroma liquid storage device, a lower aroma liquid storage container, a pressure chamber, and an aroma liquid in the lower storage container. A supply passage that supplies the pressure chamber, a bubble removal passage that communicates the lower storage container and the pressure chamber, an opening/closing member that opens and closes the bubble removal passage, and an oil-repellent coating formed on a part of the wall of the pressure chamber. It is composed of a discharge nozzle, a piezo-type pressure generation means that causes a sudden pressure increase in the aromatic liquid in the pressure chamber, and the discharge nozzle, a closing member discharge, a supply passage, a pressure chamber, and a pressure generation means. is placed at a position lower than the liquid level of the lower storage container, and discharges and stops minute droplets of aromatic liquid from the discharge nozzle in response to an electrical signal.

[0009]

[Operation] Discharge nozzles are installed at a position lower than the liquid level of the aromatic liquid in the upper and lower aromatic liquid storage containers, and a positive static pressure is always applied. offset the pressure. By coating the nozzle opening surface with a fluorine-based oil-repellent substance, it acts on the contact angle for the aromatic liquid, and the aromatic liquid does not flow out of the nozzle, forming a good convex meniscus at the nozzle opening. do.

[0010] When the air conditioner is operated, the drive voltage, drive frequency, drive time, etc. of the electric signal input to the piezoelectric vibrator, which is the pressure generating means, is controlled via a control unit such as a remote control, thereby controlling the minute amount of discharge.

Furthermore, if air bubbles are sucked into the pressure chamber for some reason when removing the cassette type scent generator, the spherical closing member that closes the air bubble removal passage under its own weight should be removed from the cassette holder. The bubbles are moved horizontally from the bubble removal passage by suction or the like using an electromagnet installed in the bubble removal passage. As a result, the bubble removal passage is wide open, and the bubbles rise from the pressure chamber in the bubble removal passage, move toward the lower storage container, and are removed. When the electromagnet is turned off, the bottom of the lower storage container tapers toward the center, so the closing member rolls back to its original position. As a result, the bubble removal passage is closed, the pressure chamber and the lower storage container are communicated only through the supply passage, and the pressure generated by the pressure generation means is effectively applied to the nozzle portion.

When the aromatic liquid in the lower storage container is consumed, the consumed amount is supplied from the upper storage container, and the upper storage container is replaced with air. Therefore, the static pressure acting on the nozzle remains constant until the aromatic liquid in the upper storage container is empty, so if the electric signal is constant, the discharge amount will also be constant.

[0013]

[Example] Example 1 of the present invention will be described below with reference to the drawings.
4 will be explained in detail.

(Embodiment 1) FIG. 1 is a perspective view of a fragrance generating device according to Embodiment 1 of the present invention.

In FIG. 1, 1 is a cassette type fragrance generating device, 2 is an aroma liquid storage container, 3 is an electric signal, 4 is a nozzle, 5 is a body, 6 is a holder, and 7 is a lead electrode PC board. That is, the fragrance generating device 1 generally includes a storage container section 2 that stores an aromatic liquid, and a body section 5 that has a nozzle 4 that discharges minute droplets of the aromatic liquid in response to an electric signal 3. For example, the scent generating device 1 is a cassette type that can be attached to and detached from an air conditioner (not shown). It is clamped and fixed in contact with a lead electrode PC board 7 which also serves as a contact point for taking out a lead from a piezo electrode (not shown) and a bottom plate of the fragrance generating device.

FIG. 2 is a cross-sectional view of the fragrance generating device according to the first embodiment of the present invention. In FIG. 2, 21 is a lower storage container;
22 is an upper storage container, 8 is an aromatic liquid, 9 is a pressure chamber, 10 is a supply passage, 11 is a bubble removal passage, 12 is a closing member, 13
14 is a diaphragm, 14 is a piezo plate, 15 is an oil-repellent coating, 16 is a recess, 17 is a lead electrode plate, 18 is a lead wire, 19 is a ventilation hole, and 20 is a supply port.

That is, the metal storage container section 2 is divided into a lower storage container 21 and an upper storage container 22, and each storage container 21 and 22 contains an aromatic liquid 8, such as various kinds of aromatic liquids having fruit or flower scents. Contains esters and their mixtures. A metal body section 5, which is an engine section that discharges minute droplets of aromatic liquid 8 in response to electrical signals 3, is coupled to the bottom of the lower storage container 21. A pressure chamber 9 having a conical or dome-shaped upper part is formed in the body part 5, and the pressure chamber 9 penetrates the body part 5 in a substantially vertical direction and supplies the aromatic liquid 8 from a storage container. Supply passage 10
This communicates with the approximate bottom of the lower storage container 21. The pressure chamber 9 also has a bubble removal passage 1 formed at its top.
1, it can communicate with the inside of the lower storage container 21. The bubble removal passage 11 is normally closed by a closing member 12, which is housed in the lower storage container 21 and has a spherical shape, for example, located at the lower part of the tapered part 29 provided at the top of the body part 5. There is. This closing member 1
The shape of 2 or the material constituting it may be any shape as long as the bubble removal passage can be opened and closed, and the material may be made of a ferromagnetic material that is attracted by magnetic force, such as a steel ball.

A metal diaphragm 13 is provided to close the bottom of the pressure chamber 9, and a piezo plate 14 is bonded to the surface of the diaphragm 13 on the side opposite to the storage container. In addition, the pressure chamber 9
A nozzle 4 for discharging minute droplets of aromatic liquid 8 is provided on a part of the wall surface, and at least the air side surface of this nozzle 4 is filled with a fluorine-based oil repellent material, particularly tetrafluoroethylene-hexane. Fluoropropylene copolymer (commonly known as FEP), tetrafluoroethylene polymer (commonly known as PTF)
An oil-repellent film 15 typified by a fluororesin coating film such as E) or a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (commonly known as PFA) is formed by means such as coating and sputtering. This nozzle 4 surface is disposed at the bottom of a recess 16 formed in the body portion 5 to protect the nozzle 4 surface from external force. Furthermore, in order to take out the electrodes from the piezo plate 14 at the bottom of the body part 5, the insulated side of a lead electrode plate 17 formed of, for example, a single-sided copper-clad laminate is adhered to the body part 5, and from the electrode surface of the piezo plate 14. The other end of the lead wire 18 drawn out by bonding or the like is connected to the copper foil side of the lead electrode plate 17. In addition, a small ventilation hole 19 is provided at the top of the lower storage container 21 to constantly communicate with the outside air.

FIG. 3 is a sectional view for explaining the operation of the fragrance generating device of the present invention having the configuration shown in FIG.

In FIG. 3, 23 is the lower liquid level, 24 is the upper liquid level, P1 is the static pressure from the nozzle 4 to the lower liquid level, and P2
is the static pressure from the nozzle 4 to the upper liquid level.

[0021] The operation of the fragrance generating device 1 made with the above configuration will be explained. Holder 6 and lead electrode PC attached to the air conditioner side where the scent generator 1 is not shown
When set between the plates 7, the position of the nozzle 4 is at the lower liquid level 2.
3, a positive static pressure P1 acts on the nozzle 4 opening. Since the surface of the nozzle 4 is coated with an oil-repellent coating 15, even liquids with a surface tension of around 25 dyne/cm, such as aromatic liquids, do not drip from the nozzle 4 and are convex at the opening of the nozzle 4. A stable state is maintained by forming a well-shaped meniscus. For example, radius r of nozzle diameter 4
is 0.025 mm, and the surface tension γ of the liquid is 25 dyne/c.
m, the density of the liquid ρ is 0.9 g/cm3, the acceleration of gravity g is 980 cm/sec2, and the contact angle θ is 60°, then the meniscus holding pressure P is 17c from (Equation 1) shown below.
It becomes more than mAq. That is, static pressure P1 of 17 cmAq or less
This means that no liquid drips from the nozzle 4.

[0022]

[Math 1]

In such a state, the electric signal 3 is transmitted by a drive control circuit via a remote control (not shown) or the like.
When is applied to the electrodes on both sides of the piezo plate 14 via the holder 6 and the lead electrode PC board 17, the closing member 12 normally completely closes the bubble removal passage 17, causing the displacement of the piezo plate 14, which is the source of vibration. The displacement of the diaphragm 13 caused by this causes a sudden pressure rise in the aromatic liquid in the pressure chamber 9, which causes minute droplets to be ejected into the air from the nozzle 4 according to the electric signal 3, and evaporate in the air. Otherwise, it adheres to a droplet receiver, a heating plate, etc. (not shown), and then evaporates, producing a scent. The aromatic liquid 8 is supplied to the pressure chamber 9 through the supply passage 10 by the static pressure P1 of the aromatic liquid and the action of the diaphragm 13 and the piezo plate 14 returning to their original positions. Since the negative pressure and the static pressure P1 of the aromatic liquid cancel each other out, the pressure acting on the meniscus of the nozzle 4 is extremely small. Therefore, as a basic structure, suction of air bubbles and unnecessary ejection do not occur.

A small ventilation hole 19 having a predetermined diameter is provided at the top of the lower storage container 21 to minimize the leakage of fragrance during rest, and to prevent the inside of the lower and upper storage containers 21 and 22 from being affected by temperature and pressure. It has the function of eliminating pressure changes. In addition, by working together with the lower and upper containers 21 and 22, the influence of the volume change accompanying the consumption of the fragrance liquid 8 on the static pressure is eliminated, and basically the liquid level remains constant regardless of the liquid level position of the fragrance liquid 8. It has the function of providing static pressure. In other words, upper container 2
Since the pressure in the upper container 22 is equal to the atmospheric pressure, the static pressures P1 and P2 are almost the same, and the static pressure actually acting on the nozzle is P1.Moreover, as long as there is aromatic liquid in the upper container 22, the lower liquid level will be This is because the static pressure is kept constant.

Further, even when the aromatic liquid in the upper storage container 21 is discharged, the lower liquid level 23 drops momentarily, but the aromatic liquid in the upper storage container 22 is disposed at the bottom of the upper storage container 22. It flows out from the tubular replenishment port 20 and is replenished into the lower storage container 21, and instead, the upper storage container has a replenishment port 20.
Air enters through the opening, and the lower liquid level 23 and the opening surface of the replenishment port 20 are brought into contact with each other again, and the height of the lower liquid level 23 returns to its original position. At this time, the pressure within the upper container 22 is again in equilibrium with the atmospheric pressure. Therefore, the lower liquid level 23
does not change until the aromatic liquid in the upper storage container 22 is completely exhausted, and the static pressure applied to the nozzle 4 also remains constant. as a result,
Since changes in the discharge amount due to changes in the liquid level can be prevented, the load on the drive control circuit is reduced. Furthermore, it is also possible to increase the total capacity by extending the capacity of the upper storage container 22 in the height direction beyond the capacity corresponding to the meniscus holding pressure shown in (Equation 1). Further, by downsizing the lower storage container 21 and keeping the lower liquid level low, changes in the discharge amount after the aromatic liquid is no longer present in the upper container 22 can be minimized.

On the other hand, if air bubbles are mixed in for some reason during use of the device, the closing member 12 is released from the closed state blocking the air bubble removal passage 11 by a predetermined means such as tilting the container. Taper portion 29
All you have to do is move it from the lower part to the periphery.

(Example 2) FIG. 4 is a sectional view showing a state in which air bubbles are sucked into the pressure chamber in Example 2, and FIG. 5 is a cross-sectional view of Example 2.
FIG. 3 is a partial cross-sectional view showing an operating state when air bubbles sucked from a pressure chamber are removed in FIG.

In FIGS. 4 and 5, 25 is a bubble;
6 is an electromagnet. The basic configuration of the second embodiment is the same as that of the first embodiment, and when air bubbles 25 are sucked into the pressure chamber 9 for some reason, the air bubbles 25 rise within the pressure chamber 9 due to buoyancy.
The bubbles accumulate near the bubble removal passage 11 which is closed by the closing member 12. In the second embodiment, an electromagnet 26 provided close to the back of the scent generating device 1 is excited by an input signal to generate a spherical closing member 1 made of a ferromagnetic material such as steel.
2 is attracted to the electromagnet 25 side.

Then, the air bubble removal passage 11 formed at the top of the pressure chamber 9 is opened wide, and the air bubbles 25 easily pass through the air bubble removal passage 11 due to buoyancy and move toward the lower storage container 21, and the air bubbles 25 are moved to the lower storage container 21 side. removed from Then electromagnet 2
When the input signal 6 is turned off, the closing member 12 closes the lower storage container 21.
Due to the inclination of the tapered portion 29 formed at the bottom of the container, it naturally rolls back to its original position and closes the bubble removal passage 11.
The original normal closed state shown in FIG. 2 is restored.

(Embodiment 3) FIG. 6 is a cross-sectional view showing the structure of Embodiment 3 with a different supply passage, and FIG. 7 is a top view of the bubble removal passage of Embodiment 3, which is different in structure from Embodiment 1. The key points are how and where the supply passages are formed.

In FIG. 7, 27 is a notch groove. As shown in FIG. 6, the supply passage 10 includes a bubble removal passage 1.
The closure member 12 is formed by contacting at least one notch groove 27 formed in the wall surface of the embodiment 1, and can be processed more easily than in the embodiment 1, such as integral molding of the closure member. It has a structure that can be formed by The operations, effects, etc. in this configuration are similar to those described in Example 1 or Example 2, so detailed description will be omitted to avoid duplication.

(Embodiment 4) FIG. 8 is a cross-sectional view showing the structure of Embodiment 4, which has a different supply passage structure similar to Embodiment 3, and FIG.
3 is a top view of the bubble removal passage section of Example 4. FIG.

In FIG. 9, 28 is a protrusion. As shown in FIG. 8, the supply passage 10 is formed by contacting the closing member 12 with at least one small protrusion 28 provided on the wall surface of the bubble removal passage 11. In comparison, it has a structure that can be formed with simpler processing. The operations, effects, etc. in this configuration are similar to those described in Example 1 or Example 2, so detailed description will be omitted to avoid duplication.

[0034] The structure, operation, function, etc. of the fragrance generating device of the present invention have been explained above, but the constituent materials of the fragrance generating device may include transparent or translucent materials such as glass, ceramics, and plastics in addition to metal. It may be configured so that the remaining amount of aroma liquid can be visually confirmed. Furthermore, in this case, molding is more effective in reducing costs.

It should be noted that the present invention is not limited to the above fragrance generating device, but can of course also be used as a droplet control device such as an inkjet recording device that requires high-speed response.

[0036] Furthermore, the oil-repellent coating can be provided on the entire surface or a part of the discharge nozzle depending on the needs.

[0037]

As described above, the present invention maintains the static pressure of the liquid at a constant level by dividing the storage container into a lower storage container and an upper storage container, and the nozzle is placed at a position lower than the liquid level in the lower storage container. By providing static pressure of the liquid to offset the negative pressure generated in the pressure chamber, it prevents air bubbles from entering, and by applying an oil-repellent coating, the meniscus is always maintained stably, stabilizing discharge and improving efficiency. can be achieved.

Furthermore, if air bubbles are mixed in, the movable spherical closing member housed in the lower storage container will prevent air bubbles from entering.
By creating a structure in which air bubbles can be easily removed from the air bubble removal passage provided at the top of the pressure chamber, for example by the suction force of an externally attached electromagnet, it is possible to provide a highly reliable piezo-driven scent generator. .

[0039] Furthermore, since the present fragrance generating device is of a droplet discharge type, it has the advantage that the fragrance components hardly change from the beginning of use to the end of use.

[0040] Since the fragrance generating device according to the present invention has a simple configuration, it can be installed in small air conditioners for automobiles and general households without any problem.

Furthermore, by making it into a removable cassette type, it is possible to select the scent that suits each person's taste by having a large variety of aroma liquids available, and it is possible to use it in each room of the home or office at an affordable price. It is possible to create a scented space that suits each person's taste, and the effects are great, such as being able to stabilize and uplift the mind and improve the efficiency of office work.

[Brief explanation of the drawing]

[Fig. 1] A perspective view of a fragrance generating device in an embodiment of the present invention.

[Fig. 2] A cross-sectional view of the fragrance generating device in the first embodiment of the present invention.

[Fig. 3] Cross-sectional view for explaining the operation of Fig. 2

[Figure 4] Cross-sectional view showing the state in which air bubbles are sucked into the pressure chamber

[Figure 5] Partial cross-sectional view for explaining the operation of removing air bubbles from the pressure chamber

FIG. 6 is a cross-sectional view of a fragrance generating device according to a second embodiment of the present invention.

[FIG. 7] Partial top view for explaining FIG. 6

FIG. 8 is a cross-sectional view of a scent generating device according to a third embodiment of the present invention.

[Fig. 9] Partial top view for explaining Fig. 9

[Figure 10] Configuration diagram of a conventional scent generator

[Figure 11] Cross-sectional view of a conventional piezo-driven inkjet head

[Explanation of symbols]

1. Fragrance generator 3 Electrical signal 4 Nozzle 6 Holder 7 Lead electrode PC board 8. Aromatic liquid 9 Pressure chamber 10 Supply passage 11 Bubble removal passage 12 Closing member 13　Vibration plate 14 Piezo board 15 Oil repellent coating 17 Lead electrode plate 18 Lead wire 19 Ventilation hole 20 Supply port 21 Lower storage container 22 Upper storage container 23 Lower liquid level 24 Upper liquid level 25 Air bubbles 26 Electromagnet 27 Notch groove 28 Protrusion 29 Taper part 30 Ink 200 cylinder 300 Control circuit 400 Piping 500 Spray amount control valve 600 Spray nozzle

Claims (13)

[Claims] 1. An upper liquid storage container, a lower liquid storage container communicating with the upper liquid storage container and having a constantly constant liquid level height, a pressure chamber, and a lower liquid storage container communicating with the lower liquid storage container and the pressure chamber. a supply passage that supplies liquid in the storage container to the pressure chamber; a bubble removal passage that communicates the lower storage container and the pressure chamber; a movable closing member that opens and closes the bubble removal passage; and a vicinity of the pressure chamber. a discharge nozzle formed on the surface thereof and coated with an oil-repellent material; and pressure generating means for causing a sudden pressure increase in the liquid in the pressure chamber in response to a predetermined signal; An integrated droplet generator for discharging and stopping minute droplets of liquid from the lower part, wherein the discharge nozzle, the closing member, the supply passage, the pressure chamber, and the pressure generating means are arranged in the lower part. A droplet generator that is always located lower than the liquid level in the storage container. 2. The integrated droplet generator according to claim 1, wherein the surface of the oil-repellent coating is made of a tetrafluoroethylene-hexafluoropropylene copolymer. 3. The integrated droplet generator according to claim 1, wherein the surface of the oil-repellent coating is made of a tetrafluoroethylene polymer. 4. The integrated droplet generator according to claim 1, wherein the surface of the oil-repellent coating is made of a tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer. 5. An integrated droplet generator according to claim 1, wherein the pressure generating means is a piezo electromechanical transducer. 6. The integrated droplet generator according to claim 1, wherein the bubble removal passage is always closed by the weight of the closing member except during a bubble removal operation. 7. The integrated droplet generator according to claim 1, wherein air bubbles in the pressure chamber are removed by temporarily moving the closing member in a substantially horizontal direction. 8. The integrated droplet generator of claim 1, wherein the closure member is spherical. 9. The integrated droplet generator of claim 1, wherein the closure member is provided within the lower storage container. 10. The integrated droplet generator according to claim 1, wherein the supply passage is formed by at least one groove formed in the wall of the bubble removal passage and a closing member. 11. The integrated droplet generating device according to claim 1, wherein the supply passage is formed by the closing member and at least one protrusion formed on the closing member. 12. The integrated droplet generator of claim 1, wherein the supply passageway is separated from the bubble removal passageway. 13. The integrated droplet generator of claim 1, wherein the mechanism for moving the closure member includes an externally provided electromagnet.