JPH09323054A - Ultrasonic atomizing vibration plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To impart durability and chemical resistance by using Pt in a specific plate thickness range as a material of a planar structure, making a cross section of through hole in a conical shape and making a narrower through hole in a specific opening diameter. SOLUTION: In an ultrasonic atomizing vibration plate 1, a lot of through holes 4 are arranged on the planar structure, and the plate 1 vibrates with an ultrasonic frequency by sticking its portion to a piezoelectric element excited by high frequency voltage and vibrating mechanically. The planar structure of the ultrasonic atomizing vibration plate 1 for atomizing a liquid in contact with the through hole 4 is made of Pt. The thickness is 20-100μm and the cross- sectional shape of the through hole is conical and the diameter of the narrower opening of the through hole 4 is 5-25μm. The thickness of the plate is decided by strength of the Pt plate and the follow-up ability to ultrasonic vibration. The diameter of the through hole is selected by a size of atomizing liquid droplets and also determined by the strength of the plate and difficulty of a formation of the hole, etc. By using Pt for all materials, the chemical resistance can be remarkably improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used in an ultrasonic atomizing device used in a humidifier for controlling indoor humidity,
The present invention relates to a diaphragm that is ultrasonically vibrated by transmitting mechanical vibration from a piezoelectric vibrator that is excited by a high frequency voltage and vibrates mechanically.

[0002]

2. Description of the Related Art A vibration plate having a large number of through holes in a plate-shaped structure is used as a vibration plate of an ultrasonic atomizing device used for a humidifier, etc., but these are conventionally made of nickel. Therefore, there was a problem in chemical resistance. About the improvement of its chemical resistance, the nickel plate obtained by electroforming is gold,
Japanese Patent Application No. 5-113114 has filed a patent application for an ultrasonic atomizing diaphragm whose surface is covered with a thin film made of platinum, palladium, rhodium or another metal or Teflon.

Conventional nickel diaphragms are corroded by the acid and oxidizing chemicals contained in the sprayed solution for the purpose of sterilization and antibacterial, and chlorine contained in tap water, and their functions are only deteriorated. However, the eluted nickel ions may be sprayed and adhere to the human body, possibly causing metal allergy. Although covering the nickel diaphragm with a highly corrosion-resistant coating (thin film) is effective in solving the above-mentioned problems, the coating is uniformly formed on the side surfaces of the holes without damaging the minute holes, and high-frequency mechanical vibration It takes a lot of labor to form a film having an adhesion strength that can withstand the above. Further, as a general method for forming a metal film, wet plating is difficult to obtain a dense film, pinholes are present, chemical components penetrate, and nickel is corroded. Further, in dry plating such as vacuum deposition or sputtering, the growth direction of the film is specified, and it is difficult to uniformly form the film on the side surface of the hole.

[0004]

The conventional ultrasonic atomizing diaphragm has problems in chemical resistance and durability, and requires a large amount of labor for mass production in terms of production technology.

An object of the present invention is to provide an ultrasonic atomizing vibrating plate which has durability and chemical resistance capable of withstanding long-term use and can be mass-produced without requiring a great deal of labor. To provide.

[0006]

In order to solve the above-mentioned problems, an ultrasonic atomizing diaphragm of the present invention has a plate-like structure provided with a large number of through holes and is excited by a high frequency voltage to cause mechanical vibration. In the ultrasonic atomizing vibration plate that vibrates ultrasonically when a part is fixed to the vibrator and sprays the liquid in contact with the through hole, the plate-shaped structure is made of platinum and has a thickness of 20 μm or more. 100 μm, the cross-sectional shape of the through hole provided is mortar-like, and the opening diameter of the narrower through hole is 5 μm.
m to 25 μm.

Since the ultrasonic atomizing diaphragm of the present invention is made of platinum not only on the surface but also inside, the liquid penetrates due to the pinholes in the plating film as in the conventional product, and further extends for a long time. There is no problem of the plating film peeling off during use, chemical resistance can be improved, and extremely long-life corrosion resistance can be obtained. Therefore, by using the ultrasonic spray vibrating plate of the present invention, chemicals other than water can be sprayed without corroding the vibrating plate and mixing of nickel or the like. The thickness of the plate is 20 to give the platinum plate strength.
If the thickness is more than 100 μm, the platinum density is high and the inertial mass is heavy, and the followability to ultrasonic vibration is deteriorated, which is not preferable. The diameter of the through hole is selected depending on the size of the droplet to be sprayed, but for the above plate thickness, it is difficult to maintain the strength of the plate if it is larger than 25 μm, and it is extremely difficult to form a hole with a circular shape of less than 5 μm. Is.

[0008]

1 and 2 show an embodiment of the present invention.
Shown in FIG. 1 is a view of the ultrasonic spray vibrating plate 1 of the present invention as seen from the liquid contact side, and FIG. 2 is a sectional view taken along line AA of FIG. The ultrasonic spray vibrating plate 1 is a platinum plate, and a large number of through holes 4 are provided therein. The opening of the through hole 4 is a small diameter opening 2 on the side where the liquid is sprayed, the large diameter opening 3 is on the side that contacts the liquid, and the through hole has a mortar-like cross-sectional shape as shown in FIG. ing.

The ultrasonic spray vibrating plate 1 of the present invention having such a structure is ultrasonically vibrated by fixing a part of it to a piezoelectric vibrator (not shown), and a liquid (not shown) in contact with the through hole opening 3 is formed. Is sprayed to the side of the through-hole opening 2 in a mist state, but since the ultrasonic spray vibrating plate 1 itself is made of platinum, no corrosion occurs even if an acidic or oxidizing substance is used as the liquid, Moreover, even if ultrasonic vibration is applied for a long time, there is no risk of peeling off a coating such as a plated coating plate. The ultrasonic atomizing diaphragm of the present invention may be manufactured by any method such as precision machining, etching and electroforming.

[0010]

EXAMPLE As an example of the present invention, a platinum ultrasonic spray vibration plate having the shape shown in FIGS. 1 and 2 was manufactured by electroforming. The thickness of the plate was 40 μm, and the diameter of the spray-side through-hole opening 2 was 10 μm. The through holes 4 were arranged at equal intervals as shown in FIG. 1 with a gap of 140 μm.

As a comparative example, an ultrasonic spray diaphragm made of nickel and having the same dimensions as those of the above-mentioned embodiment was manufactured by electroforming. Thereafter, gold plating was applied to the surface of the plate to a thickness of about 1 μm and to the inner surface of the through hole to a thickness of 0.1 to 0.2 μm.

The ultrasonic spray vibrating plates of this example and the comparative example were dipped in a flux (solvent mainly containing isopropyl alcohol for improving solderability), and the time until the occurrence of corrosion was observed was measured. In the comparative example, corrosion occurred in 2184 hours,
In this example, no corrosion was observed even after 8,000 hours. This confirmed that the corrosion resistance was significantly improved.

[0013]

According to the ultrasonic atomizing vibration plate of the present invention, the chemical resistance can be remarkably improved by making the material entirely of platinum. Therefore, by using the ultrasonic spray vibrating plate of the present invention, even if chemicals other than water are used, it is possible to spray without causing contamination such as elution of nickel or the occurrence of corrosion. From the viewpoint of mass production, the labor of forming a film of metal or Teflon on the surface is unnecessary.

[Brief description of drawings]

FIG. 1 is a diagram of an ultrasonic spray vibrating plate according to the present invention as viewed from a liquid contact side.

FIG. 2 is a sectional view taken along line AA of FIG.

[Explanation of symbols]

 1 Ultrasonic Spray Vibration Plate 2 Through Hole Opening (Spraying Part) 3 Through Hole Opening (Wetted Part) 4 Through Hole

Claims (1)

[Claims] 1. A plate-shaped structure is provided with a large number of through holes,
The material of the plate-shaped structure in the ultrasonic atomizing diaphragm that ultrasonically vibrates by partially fixing it to a piezoelectric vibrator that is excited by a high-frequency voltage and vibrates mechanically, and sprays the liquid in contact with the through hole. Is platinum and its thickness is 20 μm to 1
The ultrasonic atomizing vibration plate is characterized in that the cross-sectional shape of the through hole provided is 00 μm, and the opening diameter of the narrower side of the through hole is 5 μm to 25 μm.