JPS6287700A - Compact fan - Google Patents

Abstract

PURPOSE:To prevent a reduction in air quantity due to a difference in frequency, by connecting a plurality of displacement magnifying vibration blades to the other end of a piezoelectric vibrator, and making resonance frequencies of vibration blades to be connected to the displacement magnifying vibration blades different from each other. CONSTITUTION:A piezoelectric vibrator 1 is fixed at its one end to a support member, and is connected at the other end with displacement magnifying vibra tion blades 13a and 13b as arranged in parallel. Vibration blades 15a and 15b are connected to the displacement magnifying vibration blades 13a and 13b, respectively. The full length of a set of the vibration blades 13a and 15a is a length allowing resonance at a frequency near 50Hz, while the full length of the other set of the vibration blades 13b and 15b is a length allowing reso nance at a frequency near 60Hz. Accordingly, the fan may be driven by a com mercial power supply of 50Hz and 60Hz.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a piezoelectric vibrator used for ventilation near temperature and humidity sensors in gases, cooling of small electronic components, or blowing air of deodorizer 5 inside a refrigerator. The present invention relates to an applied small fan, and particularly to a small fan that can be driven by either 50 Hz or 60 Hz commercial power source.

[Prior art]

This type of small fan consists of a piezoelectric vibrator and metal vibrating blades made of copper, stainless steel, etc. that resonate at 50Hz and 60Hz, respectively.
(Utility Application No. 162939, filed by the present applicant) and a small fan equipped with vibrating vanes made of synthetic resin that is lightweight and has a high modulus of elasticity (Patent Application No. 60-40708, provided by the present applicant).
No.) etc.

[Problem that the invention seeks to solve]

In any of the above conventional small fans, the resonant frequency fo of the vibrating blade plate, the plate length l, the plate thickness t, the Young's modulus E of the plate material,
The relationship with the density ρ of the plate material is as follows, and when the frequency of the driving power source changes, neither the piezoelectric vibrator nor the vibrating vane plate can resonate. Even if the design is such that maximum airflow can be obtained under certain conditions, there is a problem in that a satisfactory airflow cannot be obtained if the area of use is different.

[Summary of the invention]

In order to solve the above problems, the small fan of the present invention has the following features:
．． As shown in the second figure, one end of the piezoelectric vibrator 1 is fixed to a support part, and a plurality of displacement amplifying vibrating vanes 13a and 13b are attached to the other end of the piezoelectric vibrator 1 side by side, and each displacement amplifying A small fan is provided in which vibrating vanes 15a and 15b are attached to the tips of vibrating vanes 13a and 13b, and each vibrating vane has a different resonance frequency.

By combining the displacement amplifying vibrating vanes 13a, 13b and the vibrating vanes 15a, 15b in this way, when driven by a 50Hz commercial power supply, only one vibrating vane 15a should resonate at the power frequency of 50tlz. However, the other vibrating vane plate 15b also exhibits vibration close to 50 Hz resonance as the displacement amplifying vibrating vane plate 13b is tuned. Similarly, when driven by a 60 Hz commercial power source, the opposite phenomenon occurs. That is, two sets of vibrating blade plates 13a
, 15a, 13b, and 15b interfere with each other,
When one vibrating vane plate 15a or 15b resonates, the other vibrating vane plate 15b or 15a vibrates in sync with it, so by using just one piezoelectric vibrator 1, two small fans dedicated to 50Hz and 60Hz can be combined. It has almost the same performance as the previous model, and can be made smaller, lighter, and cheaper.

In addition, compared to the conventional 50Hz and 60-email type, one of the vibrating blades only needs to satisfy the frequency range of the conventional σ door 4, so an ideal air volume close to resonance can always be obtained, and frequency dependence is reduced. As a result, the above formula (
1) Even if the temperature changes and the resonant frequency changes, the change in performance, such as scenery, will be very small, and the operating temperature range will be widened.

Furthermore, since the displacement amplifying blade plates 13a and 13b apparently play the role of driving like an upper piezoelectric vibrator, the tip displacement of the piezoelectric vibrator 1 itself may be small, so that damage to the piezoelectric vibrator 1 is almost non-existent. None.

[Detailed description of the invention]

FIG. 1 is a front view showing an embodiment of the small fan of the present invention, and FIG. 2 is a side view thereof.

First, its configuration will be explained.

In the drawing, 1 is a small, thin piezoelectric vibrator.

For example, length 20~4Qta, width 10~40fi, thickness 0
．． The size is 2 to 0.8 inches. The piezoelectric vibrator 1 may be a single-layer type consisting of a ceramic or organic membrane piezoelectric material with membrane electrodes on both sides, but it may be a single layer type made of a ceramic or organic membrane piezoelectric material with membrane electrodes on both sides, In order to obtain large vibrations, it is preferable to use a laminated type (bimorph type) in which 9.9 is laminated and membrane electrodes 3.4 are provided on the laminated surface and both surfaces.

An elastic material IJ such as silicone rubber is pasted on both sides of one end of the piezoelectric vibrator 1, and the one end is fitted into a groove in a fixing base made of two support members 10 made of vinyl chloride, etc., and these are glued together to vibrate the piezoelectric vibrator. Two vibrating vanes 13a and 13b made of metal with a high modulus of elasticity are attached to the other end of the child 1 via a connecting member 12 made of vinyl chloride, etc. Vibrating vanes 15a and 15b made of synthetic resin that are lightweight and have high elastic modulus are attached to the connecting members 14a and 14b made of vinyl chloride or the like,
When the total length of the vibrating vanes 13a and 15a of the labor union and the total length of the vibrating vanes 13b and 15b of the other labor unions are installed individually, the structure is such that the length resonates at the power frequency of around 50 Hz and around 60 Hz. .

As the material of the displacement amplifying vibrating blade plates 13a and 13b, metals such as copper, stainless steel, etc. can be used.

1. The materials of the vibrating blade plates 15a and i5b are 6 nylon, 66 nylon, modified PPO, and ABS.

Synthetic resins such as polyacetal, polyethylene terephthalate, polyetheretherketone, and polypropylene can be used. Further, these resins may be added with inorganic fillers, glass fibers, etc.

Specific gravity is 0.9-2. O9 elastic modulus is 20000-4000
0 kg/d is preferred.

Next, its effect will be explained.

50Hz or 6011 between electrodes 3 and 4 of piezoelectric vibrator 1
When the commercial power supply of Z is connected and an alternating current voltage is applied, the piezoelectric vibrator 1 vibrates 7, and the displacement amplifying vibrating vanes 13a and 13b attached to it vibrate; 13a or 13b causes the other vibrating vane plate 13b or 13a to also vibrate as if resonating via the connecting member 12. Furthermore, the vibrating blade plates 15a and 151] attached thereto vibrate.

Resonant frequency f of the vibrating vanes 15a and 15a. and board chief p
.

The relationship among the plate thickness, the Young's modulus E of the plate material, and the density ρ of the plate material is as shown in (1) 2 above.

If the vibrating vanes 15a and 15b are made of synthetic resin that is lightweight and has a high modulus of elasticity, they will be 5011z, 60! The mechanical impedance of the piezoelectric vibrator 1 is
.

- The vibration energy of the piezoelectric vibrator 1 and the vibration vane plates 13a and 13b for amplifying displacement can be transmitted to the vibrating vane plates 1.5a and 15b without waste in accordance with the dance; 15b can be bent appropriately to efficiently blow air.

Furthermore, when one vibrating vane plate 15a or 15b resonates, the other vibrating vane plate 15b or 15a vibrates in sync with it, so compared to the conventional 50Hz and 60Hz dual-use type, an ideal air volume close to resonance can always be obtained. As a result, the frequency dependence becomes very small, and from equation (1) above, even if the resonant frequency changes due to temperature changes, the change in performance such as air volume is very small, and the operating temperature range is wide, making it suitable for many fields of application. Expanded.

Table 1 shows the results of determining the air volume when changing the temperature so that the maximum air volume was obtained at 15° C. for Examples A and B and Comparative Examples a to c.

The sizes of the piezoelectric vibrators in Examples A and B are 1.
In Figure 2, length L - 25 fins x width W = 30 inches x thickness T
=0.6 It, L=25111XW=40111
XT=0.6mm, displacement amplification vibrating blade plate 13a
, 13b uses a phosphor bronze plate with plate length = 15 fins, C = U length x plate width W' - 10 mm x plate thickness t' = 0.2 m, and the sizes of vibrating blade plates 15a and 15h. is Example A
In the case of board length j? =3QtmX board width W 720 ha
x Plate thickness t-1), 2 Duplicate, in the case of Example B, plate length 1-
30mm x board width w = 28w x board thickness tm0.2
Both were made of nylon 6.

The size of the piezoelectric vibrator 1 of Comparative Example a-C is L-25va
X40=50*m X T =0.6 tm, L
=25mX W =40mmX T -0,6xx
, L = 40■W = 16flX T =
0.53, and the size of the vibrating blade plate is that of comparative example a (third
In case of figure), length R+=32m x board width W+=20mx
Plate thickness 1. =0.2 m (Vibration blade plate 1 for 50Hz
5a) and length x, = 28n
b) is made of 6 nylon, in the case of comparative example b (Fig. 4), length p0 = 30 dragon
1 mm (vibrating vane plate 15), made of phosphor bronze, comparative example C
In the case of (Fig. 4), length No. = 3 (1 wm x provisional width - 0 -
It was made of 6 nylon with 4ON×plate thickness to=o and 2 dragons (vibrating blade plate 15).

In addition, in FIGS. 3 and 4, 14 indicates a connecting member.

Table 1 In the case of this Example A and Comparative Examples a to C, as shown in Figure 5, the inner length d = 42 dragon angle x effective tube length D = 110 mm in front of the vibrating blade plates 15a, 15b, 15. In the case of Example B, a wind cylinder 16 with a size of d = 62 m square x effective cylinder length D - 110 mm is provided, and the environmental temperature is varied from 15°C to O'C using a refrigerator. 50Hz
.

The wind speed when driven at a frequency of 60 Hz was measured using a Nihon Kagaku Kogyo anemometer (ANEMOMASTERMODEL 6).
141) at point P at the exit of the wind barrel 16, and converted it into an air volume.

As is clear from Table 1 above, the preceding small fan (
Comparative example), as the temperature decreases, the above formula (1)
The Young's modulus E increases, the resonant frequency fo shifts to the higher frequency side, and at 5011z it becomes further away from the resonant frequency, and the air volume gradually decreases. On the other hand, at 60Hz, the frequency approaches the resonant frequency, and the air volume increases once, but as it becomes lower, the piezoelectric constant of the piezoelectric vibrator ρ and the bending of the vibrating vane disappear, resulting in a slight decrease. Although a decrease in air volume due to a decrease in the piezoelectric constant and the bending of the vibrating vane is unavoidable, the decrease in air volume can be dramatically suppressed.

As described above, according to the present invention, one end of the piezoelectric vibrator 1 is fixed to the support part, and the displacement amplifying vibrating vanes 13a and 13b are attached side by side to the other end of the piezoelectric vibrator 1. A vibrating blade plate 15a is attached to the vibrating blade plates 13a and 13b for expansion.
, 15b, and the total length of the vibrating vane plates 13a, 15a of the union and the vibrating vane plate 13b of the other union.
, 15b is configured to have a length that resonates at around 50Hz and 60Hz of the power frequency when installed individually, so one of the vibrating vanes 15a or 15
b is resonating, the other vibrating blade plate 15b or 1
5a will vibrate in sync, so 50Hz,
Not only can it be driven with a 60Hz commercial power source, but it can also keep air volume fluctuations to an extremely small level even when the environmental temperature changes.

[Brief explanation of drawings]

FIG. 1 is a front view showing an embodiment of the small fan of the present invention, FIG. 2 is a side view thereof, and FIGS. 3 and 4 are front views and FIGS. FIG. 5 is an explanatory diagram showing the wind speed measurement state of the present example and the comparative example. ■... Piezoelectric vibrator, 10... Supporting member, 12... Connection member, 13a, 13b...
...Displacement amplification vibrating blade plate, 14a, 14b・
...Connecting member, 15a, 15b...
Vibrating vane. Treasure 1 note 3 seedlings Answer q Fuki 52

Claims (1)

[Claims] One end of the piezoelectric vibrator is fixed to a support part, a plurality of displacement amplifying vibrating vanes are attached to the other end of the piezoelectric vibrator, and a vibrating vane is attached to the tip of each displacement amplifying vibrating vane. A small fan characterized in that each vibrating blade plate has a different resonance frequency.