JPS5829379A - Electrostatic generator - Google Patents

Abstract

PURPOSE:To conduct generation by a simple structure wherein an electrode whereon a sheet-like electret is stuck and an opposite electrode arranged parallel to the surface of the former electrode whereon the electret is put are rotated relatively to each other. CONSTITUTION:An electrostatic generator has an electrode 11 whereon a sheet- like electret 10 is stuck, and an opposite electrode 12 which is arranged parallel to the surface of the electrode 11 whereon the electret is put. The two electrodes 11 and 12 are rotated relatively to each other, thereby the opposite areas of the electret 10 and the opposite electrode 12 are varied continuously, and an AC voltage generated between these electrodes 11 and 12 is supplied to a load 13.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrostatic generator using an electric left.

Examples of such electrostatic generators are currently being used in armchair microphones and pickups, but in this example, alternating current is obtained by vibrating the electrode in the electrostatic field created by the electric left, so the rotational speed is low. It cannot be used as a sensor to detect rotational irregularities, etc., and is also unsuitable as a device for extracting electric power.

On the other hand, as a device that generates electricity using rotational motion,
Some are known to obtain alternating current by rotating an electrode near the center of a spherical shell (electret), and others are known to obtain alternating current by rotating a disk supporting an electret between two parallel fixed electrodes. . However, the former method requires the preparation of a spherical shell-shaped electric left, which is difficult to manufacture, and also makes it difficult to increase the current due to its structure.

On the other hand, in the latter case, as shown in FIG.
If they are arranged at equal intervals on the same circumference of the disk, the structure becomes very complicated, and the electret 1 and both electrodes 3 and 4 must be insulated from each other. It is extremely troublesome to manufacture.

The present invention has been made in view of the above points, and an object thereof is to provide a rotary electrostatic generator that has a simple structure and is easy to manufacture.

The present invention will be explained below with reference to FIGS. 2 to 12 of the drawings.

FIG. 2 is a schematic diagram showing the basic principle of the plexus electric generator according to the present invention. The electrostatic generator according to the present invention includes an electrode 11 to which a sheet-like electret 10 is adhered, and a counter electrode 12 arranged parallel to the electret-adhesive surface side of the electrode 11, and the electrodes 11 and 12 are placed relative to each other. The electret 10 rotates to continuously change the facing area of the electret 10 and the counter electrode 12, and generates an alternating current voltage in the load 13 connected between the electrodes 11 and 12. In addition, in the example shown in the figure, the load 13 is applied between both electrodes 11 and 12! ! The appearance is electrode 11
Although this is done by connecting the electrode 12 to the ground via the load 13, the load 13 may be connected to the electrode 11 side. However, since the electrode to which the load 13 is connected must be insulated from the ground, the load should be placed on the fixed electrode! I want to be in control,
The structure will be simpler if the rotating electrode is grounded.

Therefore, in the illustrated example, the electrode 11 is a rotating electrode, and the electrode 12 is a rotating electrode.
It is preferable to use the electrode as a fixed electrode.

Now, suppose that the electrode 11 is a rotating electrode and the electret 10 attached to the electrode 11 is charged so that the side facing the electrode 12 is negative as shown in the figure. In the steady state, where the third
As shown in FIG.
The surface of the electrode 12 facing 0 is 10, and the opposite surface is -
A current for charging the load 13 starts flowing to the load 13.

Then, at a time point t2 when the facing area begins to decrease, a current begins to flow to the load 13 to release the ten charges charged on the surface of the electrode 12.

The way the above current flows depends on the size of the load, and the load 1
3 is a resistor, and when the opposing area of the electret 10 and the opposing current 12 changes linearly with time as shown in FIG.
A voltage with a waveform as shown in figure (bl) will be generated in the load 13. Waveforms This is from the time of.

Note that, as shown in FIG. 3(a), if the next facing of the electric left 10 and the facing electrode 12 is started immediately after the facing area becomes zero, the variant shown in FIG. 3 can be obtained. Different alternating voltages are generated.

As the simplest example for this purpose, as shown in FIG. 4, a semicircular electret 10 is attached to a disk-shaped electrode 11, and the counter electrode 12 is formed in a semicircular shape.

Note that since the rotating electrode is rotatably supported by a bearing, it can be connected to ground or a load via this bearing, but if the contact resistance at the bearing is large, it may be necessary to connect it to a sliding ring such as a sliding ring. It is preferable to connect via a moving member.

By the way, the power, which is the product of voltage and current generated by the electrostatic generator according to the present invention described above, increases in proportion to the surface charge density and thickness of the electret, and inversely to the distance between the electrodes. Since the surface charge density of the electreft depends on the distance between the electrodes and the thickness of the electret, it is necessary to set the distance between the electrodes to a certain degree or more depending on the thickness of the electreft. Moreover, the values of the voltage and current generated depend not only on the load resistance mentioned above but also on the relative rotational speed.

Now, when the rotation speed is constant, the current is constant and the voltage increases linearly until the load resistance reaches a value, but when the load resistance exceeds that value, the current decreases and the voltage increases at the rate of increase. decreases and eventually reaches saturation.

On the other hand, when the rotation speed increases by n times, the current value increases by n times, but the so-called constant current region where the current value is constant regardless of the size of the load resistance becomes 1/H, and if the load resistance is much smaller The voltage reaches the saturation voltage region.

Therefore, if the load is a resistor and the facing area of the electret and the counter electrode changes linearly in proportion to time as shown in Figure 3 (Ml), the voltage waveform will be rectangular in the constant current region. waveform (waveform For example, a waveform as shown by 2 in FIGS. 3-) is obtained.

However, the effect obtained on the voltage and current values and their waveforms when the rotational speed is increased is that when the configuration shown in Fig. 2 is used as a unit configuration, the number of both counter electrodes and electrets in this unit configuration increases. increasing the number of unit configurations themselves and connecting them in parallel,
Alternatively, it can be obtained by combining both of these.

Now, there are two ways to increase the number of unit structures in the form of an integral structure. One of them is, taking a two-unit structure as an example, the fifth
As shown in the figure, electrets 20 are placed on both sides of the electrode 21.
1 and 202, the outer surface charges of these electric lefts 20+ and 202 have the same polarity, and two opposing electrodes 221 and 202 are connected to each other so that both sides of the electrode 21 have the same potential. 222 are arranged in parallel, and the load 13 is connected between the electrode 221 and the ground.

In the case of a four-unit configuration, as shown in FIG. 6, two unit configurations are connected in parallel and electrostatic shielding is provided between them by an electrostatic shielding plate 23. Since this shielding plate 23 is grounded, in the actual configuration, the electret 20+
and 202 are attached to the electrode 21, and the electrode 21' to which the electrets 20+' and 202' are attached are integrated. The configuration method described above is suitable for configurations of even units.

Taking a two-unit configuration as an example, as shown in FIG. 7, the second method is to attach electrets 3o1 and 302 to one side of electrodes 311 and 312 facing the same direction, respectively, and to attach these electrets to 7) 301 and 3
The outer surface charges of 02 have the same polarity, and the electrode 311
and 312, opposite electrodes 321 and 322 are arranged in parallel on the respective electroleft sticky surfaces.

According to this method, two or more units are repetitions of exactly the same one unit configuration, so it is suitable for either even or odd unit configurations.

As for the shape of the electrode, in addition to the disk shape shown in FIG. 4, a cylindrical shape can be considered. A disc-shaped electrode is suitable for a structure with a small number of poles and many units, whereas a cylindrical electrode is suitable for a structure with a large number of poles and a single unit.

Figures 8(a) and (bl) are a simplified plan view and saw cross-sectional view, respectively, of an electrostatic generator with four poles and one unit configuration when disc electrodes are used, but the configuration is clearly shown. Therefore, in Figure 0, the thickness of the electret is exaggerated compared to the thickness of the electrode, electret 40] to 404
The electrode 41 to which is attached is the rotor, and the center hole 41a
A rotating shaft (not shown) is fitted into the shaft, and the shaft is grounded via the rotating shaft, bearing, etc. An electrode 42, which is electrically distributed parallel to the electrode 41 on the electroleft sticky surface side, is a stator, and its outer peripheral portion is held by the housing via an insulator. The electrode 42 consists of four fan-shaped electrode parts 421 to 424 that are connected to each other at the outer periphery, and the electrode parts 421 to 424 are arranged at equal intervals of 90 degrees. On the other hand, the electrets 401 and 402 are formed in the same shape as each of the fan-shaped electrode portions, and when the electrode 41 rotates, the electrode portions 421 and 42. The electrodes 41 are attached to the electrodes 41 at equal intervals of 90° on the same circumference so as to face each other.

Figure 9 is a simplified cross-sectional view of an electrostatic generator with 6 poles and one unit configuration when cylindrical electrodes are used, and as in Figure 8, the thickness of the electret is exaggerated. There is. In the figure, electrets 501 to 506 are 60
Cylindrical electrodes 51 that are adhered to the outer circumferential surface at equal intervals of ° are the rotor, and the rotor is rotatably supported in the housing by a rotating shaft that is inserted into a hole 51a bored along the axis of the rotor. , it is designed to be grounded via a bearing, etc.

A cylindrical counter electrode 52 arranged concentrically around the outer periphery of the electrode 51 is a stator, and is supported by the housing via appropriate insulating means. The electrode 52 has window holes 52a formed at equal intervals of 60° to form electrode portions 52+ to 52@.
is formed. The length l of the window hole 52a is approximately equal to the length of the electret, as can be seen from FIGS. Electre for the difference/
) is larger than the width of

In the electrostatic generator having the configuration shown in FIG. 8, the thickness and diameter of the electrode 41 are 0.5fi and 900, respectively, and the hole 41M.
The diameter of the electric left is 10 Tsuru, the thickness of the electric left, the opening angle of its fan shape, and the radius are 12 μm, 22.5° and 45fi.
, the height of the triangle at the cut-off tip of the fan-shaped electret is 10fi, the thickness and outer diameter of the electrode 42 are 0.5fi and 106cm, respectively, and the shape of each electrode part is the same as the electret throat, When the distance between the rotor and the fixing member is 0.5fi, the material of both electrodes is aluminum, the material of the electric left is FEP Teflon, and the strength of the electric left is 1O-IC/- on average,
When the rotation speed of the rotor is changed using the load resistance as a parameter, the peak voltage value as shown in Fig. 11 is obtained, and when the load resistance is changed using the rotation speed as a parameter, the peak current value as shown in Fig. 12 is obtained. Obtained.

As is clear from Fig. 11 and Fig. 12, when the rotation speed of the rotor is 1000, 3000 and 5000 rpm, constant currents of 2μA, 6μA1 and 10μA are obtained corresponding to each rotation speed, and in that region. The ranges of the load resistances are 0 to 15.0 to 5 and 0 to 3 MΩ, respectively.

And the saturation voltage is 70V.

In the above specific example, when the rotation speed is 5ooorpm, the maximum power obtained in the constant current region is 3 mW (load resistance 3 MΩ, output voltage 30 V, current 10 μA),
The number of poles is 1.5 times 6! By rubbing 304, which is 1.5 times more than the number and 30 times the number of constituent units, it is 30 times more.
0 times and can be further increased by increasing the thickness of the electret and its average strength. (Related to this, the saturation voltage will naturally increase.Furthermore, by increasing the thickness of the electret and correspondingly increasing the distance between the electrodes, the capacity of the generator can be increased. Both voltages will further increase.In addition, if this generator is sealed in a highly insulating gas of 10-4 Hg or more in a high vacuum, it is possible to further increase the power and saturation voltage. I can do it.

In the specific example described above, the size of the electrode is large, but in the case of a rotation speed sensor, a disc electrode with an external diameter of 35 days, a length of about 106 mm, and a cylindrical Uses electrodes, outer diameter 20fi, length approximately 20fi
It can be made small.

As described above, the present invention involves relatively rotating an electrode to which a sheet-shaped electret Fret is adhered and a counter electrode to which electricity is distributed parallel to the electret adhesive surface of this electrode, so that the opposing area between the electret and the counter electrode is is changed continuously to generate an alternating current voltage across a load connected between both electrodes.

For this reason, there is no need for special members to support the electric left as in the past, and the structure is simple and easy to manufacture, making it possible to create a small, inexpensive electrostatic generator with fewer troubles. You will be able to do it.

Further, since it is easy to make the electrodes multipolar and increase the number of constituent units, it is easy to obtain a generator that generates a large output. Therefore, it can be used as an effective f1 heavy electric machine as a power source for an electrostatic motor such as a corona motor.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram showing an example of a conventional rotary electrostatic generator.
FIG. 2 is a schematic diagram showing an embodiment of the electrostatic generator according to the present invention, FIG. Figure 4 shows the simplest structure of the electrostatic generator shown in Figure 1! Li,? FIGS. 5 to 7 are schematic diagrams showing other embodiments of the electrostatic generator according to the present invention, and FIGS. FIG. 9 is a plan view and side sectional view showing a specific example of the electrostatic generator according to the present invention using cylindrical electrodes, FIG. Figures 11 and 12 are graphs respectively showing the voltage and current characteristics of the electrostatic generator in a specific example. 10, 201. 202,20r'-202'
, 301. 30s, 40+ to 4O-15 (h to 506...electret 11=21.21', 311 -312 .41°51...electrode 12.22+, 222.221', 222'
, 321. 32□, 42, 52...Counter electrode 13...Load Patent applicant Takko Seiki Seisakusho Co., Ltd. Procedural amendment (July 16, 1981 41Hv - Hikan Wakasugi Kazuo 1, □Tonmo 56 Year 1 No. 126003 3, Person making the amendment 4, Agent 8, Contents of the amendment Contents of the amendment as shown in the attached sheet (Japanese Patent Application No. 126003, 1983) 1, Page 1 of the specification, line 19 “Yamataru Mura” 2. Insert "of the same frequency as the number of revolutions" before "alternating current" on page 3, line 9 of the same book. 3. Insert "of the same frequency as the rotation speed" on page 3 of the same book, line 1θ, before "nao". Insert the meaning of the sentence. ``In the simplest example of this generator, as shown in No. 3 [I!J], a semicircular electret 10 is attached to a disc-shaped electrode 11, and the opposite electrode 12 in a semicircular shape.'' 4. Insert "3rd" before "Figure" in line 1θ of page 3 of the same book. 5. Line 20 of page 3 of the same book and line 4 of page 4. Insert the following sentence between the first line and the other line: ``Since the rotating electrode is rotatably supported by a bearing, it can be connected to ground or a load via this bearing, but contact at the bearing is not possible. If the resistance is large, it is better to connect through a sliding member such as a sliding ring.'' 6. Correct "opposite side" to "remaining" in line 8, page 4 of the same book. 7. Delete page 14 to page 6, line 5 8,
In the third line of page 5 of the same book, ``Nao'' is corrected to ``And''. 9. Same book, page 5, lines 5 and 6 “Figure 3...
be done. Correct J to "An alternating current or voltage is generated continuously. The values and waveforms of said current and voltage depend on the relative rotational speed and load resistance." 10. Insert "width of" after "area" on page 6, line 13 of the same book. 11. In the same book, page 6, line 16, "therefore" is corrected to "also". 12. In the same book, page 6, line 20, after “saturation”, add “voltage”.
insert. 13. Insert the following sentence after "Obtainable." on page 7 of the same book, line 3. "In order to increase the voltage and current, it is necessary to increase the surface charge density and thickness of the electret and to narrow the distance between the electrodes, but the surface charge density of the electret depends on the distance between the electrodes and the thickness of the electret. Therefore, it is necessary to set the distance between the electrodes to a certain degree or more depending on the thickness of the electric left.'' 14, Ibid., page 8, lines 2 to 8, ``
Connect... and head. " should be corrected to "It will be connected." 15. Delete lines 17 to 19 on page 8 of the same book. 16, same book, page 11, line 4, before “10” r 2.5
Insert X J. 17. In the same book, page 11, line 45, "and small" is corrected to "naJ." 18. In the same book, page 13, lines 16 and 17, insert the following sentence. "Also, this generator Since the frequency of the generated voltage is an integral multiple of the rotation speed, it can be used as a rotation speed sensor by counting the frequency.Furthermore, in this case, the reaction of the rotor is extremely small, so the influence on the system under test is small.
It also has the excellent feature of being compact and lightweight. ” 19, page 13, line 17 of the same book, “also” is corrected to “further”. 20. The same book, page 14, lines 5 to 8, "Figure 3...Plan view" is corrected as follows. "Figure 3 is a plan view showing a simple configuration example of the electrostatic generator in Figure 1, and Figure 4 (al and (bl) are diagrams for explaining the operating principle of the electrostatic generator in Figure 2. Graph” 21, Ibid. No. 1
Page 5, line 3, ``, 222'J is deleted. n9 Drawings 1 to 7 are replaced with the attached drawings.

Claims (1)

[Claims] An electrode to which a sheet-like electleft is adhered, and a counter electrode disposed in parallel to the electleft adhesive surface side of the electrode, and the two electrodes are relatively rotated to connect the electleft and the counter electrode. An electrostatic generator characterized in that an alternating current voltage is generated in a load connected between the two electrodes by continuously changing the facing area of the two electrodes.