JP2817661B2 - Working medium and actuator for actuator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an actuator for converting electric energy into kinetic energy such as rotational motion and reciprocating motion, and a working medium thereof.

[0002]

2. Description of the Related Art Conventionally, there is no known actuator that directly converts electric energy into kinetic energy such as rotational motion and reciprocating motion by using a working medium. No. 6-175872 (filed July 27, 1994) is the only one. The actuator of this prior application includes an electro-sensitive fluid as a working medium in a housing, a plurality of electrodes provided in the housing, and a movable member for power take-out in the housing, and a voltage applied to the electrodes. The movable member is moved by the working medium by applying a voltage, and a binary mixture of an organic fluorine compound and an electrically insulating fluid is used as the electrosensitive fluid.

[0003]

SUMMARY OF THE INVENTION The inventor of the present invention has sought to further improve the performance of the actuator of the prior application.
Moreover, we studied to obtain a cheap one.

[0004]

As a result, it has been found that the above object can be achieved by selecting an ester represented by the following general formula (I) as a working medium.

Embedded image

Hereinafter, the present invention will be described in detail. FIGS. 1 to 3 show an example of an actuator according to the present invention, which is a kind of motor for extracting rotational motion. In the figure, reference numeral 1 denotes a bottomed cylindrical case (housing) made of an electrically insulating material, and a lid 2 is attached to the case 1 so as to close an opening thereof. As shown in FIG. 3, eight electrodes 3a, 3b,
3c, 3d, 3e, 3f, 3g, 3h are attached.

The electrodes 3a, 3b,..., 3h are wire-like members made of metal such as iron, copper, aluminum, etc., and are inserted through electrode support portions 4 formed on the inner peripheral wall of the case 1 to protrude. It is attached so that it may contact the wall surface of. The upper portions of the electrodes 3a, 3b... 3h are bent in an L-shape, and the slits 5 formed in the upper portion of the case 1 are formed.
Extends outside the case 1 and its end is bent in an annular shape.

In the case 1, an impeller-shaped rotor 6 is provided.
Is provided. As shown in FIG. 2, the rotor 6 comprises a rotating shaft 6a and six blades 6b attached to the rotating shaft 6a at equal intervals. The lower end of the rotating shaft 6a has a needle head shape, The pivot shaft 6 a is supported by a pivot bearing 7 formed at the center of the bottom of the case 1, and the upper portion of the rotating shaft 6 a is provided at the center of the lid 2 and extends above the case 1 via the bearing 8.

3h, lead wires (not shown) are connected to one DC power source 10 from the electrodes 3a, 3b... 3h. This DC power supply 10 is 0.5 to 10 kV
3h, and has an automatic switching function of sequentially and automatically switching and applying the output DC voltage to each of the electrodes 3a, 3b... 3h for a predetermined time as needed.

The case 1 is filled with the ester represented by the general formula (I) as the working medium 11 to such an extent that the blades 6b of the rotor 6 are substantially submerged.

The ester is a diester of a dibasic unsaturated fatty acid. Examples of the dibasic unsaturated fatty acid include maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, and other unsaturated fatty acids. Is
Saturated fatty acids consisting of glutaric acid, adipic acid, pimelic acid, and suberic acid, in which a linear main chain portion is dehydrogenated to introduce one unsaturated bond, and the like. R ₁ and R ₂ are a methyl group, an ethyl group, a butyl group, an isobutyl group, a 2-ethylhexyl group,
Examples include an alkyl group such as an isodecyl group. Specific preferred examples of the ester include dibutyl maleate, dibutyl fumarate, dimethyl phthalate, dibutyl phthalate, and bis (2-ethylhexyl) phthalate.

Next, the operation of the actuator of this embodiment will be described. Basically, a plurality of electrodes 3a, 3b,.
The rotor 6 is rotated by applying a DC voltage from the DC power supply 10 to the motor. The specific voltage application method is as follows.

First, in the first voltage application method, two electrodes, for example, the electrode 3a in FIG. 3 and the electrode 3e located at a position of 180 degrees in a plane angle with respect to the two electrodes are used as positive electrodes,
In this method, a DC voltage is applied with the electrodes grounded (negative electrode). This first voltage application method is characterized in that two fixed electrodes are used as positive electrodes, for example, and the remaining six electrodes are grounded and negative electrodes are used as voltages. In this case, a positive charge is applied from the positive DC power supply to the positive electrode, and the ground side is relatively negative. When the DC power supply is a negative-type power supply to which a negative charge is applied, a negative charge is applied to the two fixed electrodes, so that the two electrodes become negative and the ground side becomes a relatively positive.

As a modification of the first voltage application method,
A voltage is applied with the electrode 3a and the electrode 3d located at a position of 135 ° in a plane angle with respect to the positive electrode, and the remaining electrode is grounded. There is a type in which a voltage is applied using the electrode 3c as a positive electrode and the remaining electrode is grounded. Of course, a combination having the same plane angle as the combination of these electrodes, for example, the electrode 3
a and electrode 3f, electrode 3a and electrode 3g, electrode 3b and electrode 3
d and the like are also included in the first application method. However, in the arrangement of FIG. 3, a combination of mutually adjacent electrodes is excluded.

Therefore, in this first voltage application method, at least two electrodes are used as a positive electrode or a negative electrode, at least one electrode is present between these two electrodes, and these electrodes are connected to the remaining electrodes. In addition, it is desirable that the arrangement be grounded.

In this first voltage application method, it is preferable for the rotation of the rotor to make the electric field intensity between the two electrodes relatively high. For this purpose, the method of increasing the applied voltage and the case are miniaturized. And the like. Specifically, when the inner diameter of the case of FIG. 1 is 5 cm, the applied voltage is 3 kV.
More preferably, it is desirable to be 5 kV or more.

The second voltage application method is a method in which a DC voltage is sequentially switched and applied to the eight electrodes 3a, 3b... 3h in FIG. Specifically, eight electrodes 3
.. 3h, a voltage is applied with the two electrodes 3a and 3e opposed to each other across the rotation axis 6a of the rotor 6, and the remaining electrodes are grounded. After a lapse of a predetermined time, for example, one second, the voltage application is switched in the clockwise direction in FIG. 3 from the electrode 3a to the adjacent electrode 3b and from the electrode 3e to the adjacent electrode 3f. At this time, from the electrode 3e to the electrode 3f
The timing of switching to the electrode 3a is delayed from the timing of switching from the electrode 3a to the electrode 3b by a fixed time, for example, 0.5 seconds. Therefore, an extra voltage is applied to the electrode 3e for a longer time than the electrode 3a, for example, 0.5 second.

Next, after a voltage is applied to the electrode 3b and the electrode 3f for a predetermined time, for example, 1 second, the electrode 3b
, The voltage application is switched from the electrode 3f to the electrode 3g, and the switching from the electrode 3f to the electrode 3g is also delayed because the previous switching timing is delayed. In this manner, as shown in the timing chart of FIG. 4, the voltage application to the two electrodes is not switched at the same time, but one of the two electrodes is delayed for a predetermined time, for example, 0.5 seconds. To switch. Hereinafter, a voltage is applied by sequentially switching to each electrode in the same manner. In any case, the electrodes other than the two electrodes to which the voltage is applied are grounded.

In the second voltage application method, the rotor 6 rotates even if the electric field strength between the electrodes is relatively low, and the applied voltage may be 2 kV or less. This is a voltage application method suitable for a large size.

The voltage applied to the plurality of electrodes 3a, 3b... Causes the rotor 6 provided in the case 1 to rotate. Thus, the rotational motion can be extracted from the rotating shaft 6a of the rotor 6, and the rotor 6 operates as an actuator. (Positive electrode and negative electrode) can be adjusted in a planar manner to control the rotation direction of the rotor 6. That is, when the electro-sensitive fluid shows a flow from the positive electrode to the negative electrode, the rotor 6 rotates in that direction.

In such an actuator, electric energy by applying a voltage to the plurality of electrodes 3a, 3b,... Is converted into rotational motion of the rotor 6, and can be taken out as power. An actuator using such a working medium has not been known so far and has been developed for the first time by the present inventors.

In the above specific example, the number of electrodes is eight, but
As described above, any other number may be used as long as the number is two or more, and the number of rotor blades may be two or more. Also, there is no particular need to match the number of electrodes with the number of rotor blades.
Furthermore, if another voltage application method is adopted, the rotation speed of the rotor can be changed. Further, the present invention is not limited to the rotating machine described above, and a piston is arranged in a cylinder, a working medium is filled, and a plurality of annular electrodes are arranged on an inner peripheral wall of the cylinder. , By sequentially switching and applying the voltage to the electrodes,
The piston can be reciprocated.

Example 1 The actuator shown in FIGS. 1 to 3 was manufactured. The rotor 6 has six blades provided with six blades at equal intervals. As working medium,
Case 1 was filled with about 60 ml of dibutyl maleate.
DC voltage of 5.0 kV with electrodes 3a and 3e as positive electrodes
Was applied, and all the remaining electrodes were grounded to form a negative electrode. As a result, the rotor 6 started rotating immediately after the application of the voltage, and continued to rotate during the application of the voltage. The rotation speed at that time was 6.5 seconds / 1 rotation, and the current value was 0.05 mA or less, which was lower than the lower limit of measurement of the current measuring device used.

(Embodiment 2) The same working medium as in Embodiment 1,
And equipment. The applied voltage is DC 2.0 kV,
A second application method in which a voltage is sequentially switched and applied to eight electrodes is employed. The voltage application to the electrodes 3a, 3b... 3h is as shown in the timing chart of FIG. 4, the application time is 1 second, and only the first application time to the electrode 3e is 1.
5 seconds. As a result, the rotor 6 continued to rotate at a rotation speed of 18 seconds / 1 rotation. The current value was 0.05 mA or less.

(Embodiment 3) In the actuator shown in FIGS. 1 to 3, the diameter of the case 1 and the width of the blade 6 b of the rotor 6 are each set to の of that of the embodiment 1, and this embodiment is used. As in Example 1, eight electrodes 3a, 3b... 3h were additionally provided. Here, 15 ml of the working medium used in Example 1 was filled. A DC voltage was applied using the electrodes 3a and 3e as positive electrodes, and all the remaining electrodes were grounded to form negative electrodes. As a result, the rotor 6 started rotating immediately after the application of the voltage, and continued to rotate during the application of the voltage. Table 1 shows the relationship between the applied voltage and the rotation speed at that time. In each case, the current value when applying a voltage was 0.05 mA or less.

[0025]

[Table 1]

Example 4 The relationship between applied voltage and rotation speed was measured in the same manner as in Example 3 except that dibutyl phthalate was used as the working medium. The results are shown in Table 2. still,
The current value was 0.05 mA in each case.

[0027]

[Table 2]

Example 5 The relationship between the applied voltage and the rotation speed was measured in the same manner as in Example 3 except that dibutyl phthalate was used as the working medium. The results are shown in Table 2. still,
The current value was 0.05 mA or less in each case.

[0029]

[Table 3]

(Example 6) The rotation speed at the time of applying a DC voltage of 5.0 kV was measured in the same manner as in Example 3 except that bis (2-ethylhexyl) phthalate was used as a working medium. Seconds per revolution. At this time, the current value was 0.05 mA or less.

(Example 7) The rotation speed when a DC voltage of 5.0 kV was applied was measured in the same manner as in Example 3 except that dimethyl phthalate was used as the working medium. The rotational movement immediately after the application of the voltage showed a rotational speed of 35.7 seconds / 1 rotation, but thereafter the rotational movement became unstable, and it was observed that the rotational speed suddenly decreased. The current value during voltage application is 0.1
mA.

(Eighth Embodiment) In the third embodiment, the electrode 3
c, 3d, 3g, 3h are removed from the case, and the electrode 3a
And 3e were used as positive electrodes, electrodes 3b and 3f were grounded, and negative electrodes were used as negative electrodes. A direct current of 5.0 kV was applied, and the rotation direction and the rotation speed during the application were measured. Table 5 shows the results. Also, the electrodes 3d and 3h were used as the negative electrodes instead of the electrodes 3b and 3f, and the rotation direction and the rotation speed during the voltage application were measured in the same manner. The results are shown in Table 4. In both cases, the current value at the time of voltage application was 0.05 mA or less, which was lower than the lower limit of measurement of the current measuring device used.

[0033]

[Table 4]

[0034]

As described above, according to the present invention, an unsaturated dibasic acid such as maleic acid diester, fumaric acid diester, phthalic acid diester or the like is used as a working medium, and electric energy is converted into a rotational motion and a reciprocating motion. A new actuator to convert can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram illustrating an example of an actuator of the present invention.

FIG. 2 is a plan view showing a rotor of the actuator of FIG. 1;

FIG. 3 is a plan view showing an arrangement of electrodes of the actuator of FIG. 1;

FIG. 4 is a timing chart illustrating an example of a second voltage application method to electrodes in the actuator of the present invention.

[Explanation of symbols]

1 ... case, 3a, 3b, 3c, 3d, 3e, 3f, 3
g, 3h ... electrodes, 6 ... rotor, 10 ... DC power supply, 11 ...
Working medium

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F03G 7/00 C10M 105/36 C10N 40:14

Claims (3)

(57) [Claims] 1. A working medium comprising an ester represented by the following general formula (I) and used for an actuator that converts electric energy into kinetic energy. Embedded image 2. A housing, in which an ester represented by the following general formula (I) is put as a working medium, a plurality of electrodes are provided in the housing, and a movable member for taking out power is arranged in the housing. An actuator, wherein a voltage is applied to the electrode to move a movable member via a working medium. Embedded image 3. An ester represented by the following general formula (I) is charged into a cylindrical casing as a fluid medium, a plurality of electrodes are provided on an inner peripheral wall of the casing, and an impeller-shaped rotor is provided in the casing. Wherein a voltage is applied to the electrode to rotate the rotor via a working medium. Embedded image