JPH08190236A - Copier - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide a low-noise and small-sized copying machine using an acoustic wave absorption control device having an EA effect and having an ENC fluid composition whose characteristic frequency can be changed by an applied voltage. . A copying machine body 30 having a copying function is provided with a sound wave absorption control device 32 for absorbing and controlling noise generated from the copying machine body 30, and the sound wave absorption control device 32 has an electric field array effect. The solid particles 2 contained therein contain the electro-sensitive acoustic absorption control fluid composition contained in the electrically insulating medium 1, and further, a voltage is applied to the electro-sensitive acoustic absorption control fluid composition and It is connected to a voltage applying means 13 for adjusting the applied voltage.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a copying machine used as an A (Office automation) device.

[0002]

2. Description of the Related Art Hitherto, as a noise preventer for a copying machine, one using a sound absorbing box has been known. FIG. 13 (a),
(B) is a diagram showing an example of a copying machine using a sound absorbing box, in which reference numeral 50 is a copying machine main body and 51 is a sound absorbing box. The sound absorbing box 51 is provided on the outside of the side wall of the copying machine main body 50 so as to project. A hole 53 is opened on the outer surface of one end of the sound absorbing box 51 in the horizontal direction. Further, inside the sound absorbing box 51, a piston 55 configured to be reciprocally movable between the other end in the horizontal direction and the hole 53 by a driving force of a drive motor 54 is arranged. A noise detector (not shown) for detecting noise of the copying machine is connected to the drive motor 54. This copying machine absorbs noise of a specific frequency by adjusting the resonance frequency of the sound absorbing box 51 when the noise is detected by the noise detector. That is, the drive motor 54 is driven by receiving the detection signal of the noise detector, moves the piston 55, and changes the volume of the internal area of the sound absorbing box 51 including the hole 53 so that the resonance frequency corresponds to the frequency of noise. By doing so, noise is absorbed.

[0003]

In the copying machine, however, there is a problem that the amount of the sound absorbing box 51 protruding to the side is large, which causes a decrease in space utilization in the office. Further, since the hole 53 is opened toward the outside, there is a problem that the sound absorption efficiency is poor. Further, the copying machine has a problem that the efficiency of sound absorption is low because it takes time to adjust the sound absorption frequency of the sound absorption box 51 due to the movement of the piston 55. That is, the noise of the copying machine is
It is mainly the motor noise and device operation noise when moving the lens or feeding the paper, but generally the operation time of these motors and devices is short, and the noise frequency changes frequently due to switching of the operating parts during operation. Therefore, it is difficult to adjust the sound absorption frequency of the sound absorbing box 51, and there is a time during which noise is not absorbed.

By the way, the inventors of the present invention have developed a fluid composition for electro-sensitive sound wave absorption control (hereinafter referred to as "Electric Noise-Control") having a novel electric field arrangement characteristic (hereinafter referred to as "EA characteristic") which has not been known. The fluid composition is abbreviated as “ENC fluid composition”). The ENC fluid composition is, for example, a fluid obtained by dispersing solid particles in an electrically insulating medium. When an electric field is applied to the fluid, the solid particles cause dielectric polarization, and electrostatic attraction based on the dielectric polarization is generated. Have a property of exhibiting a chain structure by being coordinately linked to each other and aligned. In addition, some solid particles exhibit the property of exhibiting an array lump structure by electrophoresis and array alignment. As described above, the alignment orientation of particles under an electric field is determined by the electric field alignment effect (hereinafter, referred to as Electric Alignment).
The t effect is abbreviated as “EA effect”), and the solid particles having such properties are referred to as electric field arranging particles (hereinafter, electric field arranging particles are abbreviated as “EA particles”). . And the present inventors have found that the EN of this novel structure is
The present invention was reached by advancing research into C-fluid compositions.

The present invention has been made in view of the above circumstances, and provides the copying machine provided with the ENC fluid composition having the EA effect and capable of changing the characteristic frequency by the applied voltage. It aims to solve problems.

[0006]

In order to achieve the above-mentioned object, a copying machine of the present invention is a sound wave absorption control device for a copying machine body having a copying function to absorb and control noise generated from the copying machine body. The sonication control device contains an ENC fluid composition in which EA particles having an electric field array effect are contained in an electrically insulating medium, and a voltage is applied to the ENC fluid composition. It is characterized in that it is connected to a voltage applying means for applying and adjusting the applied voltage.

[0007]

According to the copying machine of the present invention, the voltage applying means is EN
By applying a voltage of a predetermined value to the C-fluid composition,
The sound wave absorption control device reduces sound waves of a specific frequency. Here, for example, when the frequency of noise changes due to the number of rotations of the motor inside the copying machine or the switching of the operating part of the device, the sound wave absorption control device is configured from the voltage applying means.
A voltage of a predetermined value is applied to the NC fluid composition. By doing so, the sound absorption frequency of the sound wave absorption control device changes, and the sound wave of the specific frequency that has changed depending on various conditions is reduced.

That is, in the sound wave absorption control device, the EA particles having the EA effect in the ENC fluid composition are randomly suspended and dispersed in the electrically insulating medium in the state where no voltage is applied. When a voltage is applied to the pair of electrode plates by the voltage applying means, the EA particles are arrayed and linked in a chain to form a chain (particle chain), and the chain is aligned parallel to the electric field direction. When a sound wave (air vibration) is applied to one of the electrode plates in this state, the electrode plate vibrates in the opposite direction, but the chain body itself has elasticity, so the chain body is stretched. When the particles are opposed to each other, they attract each other to generate an attractive force, and when they are compressed, they bend to generate a repulsive force, which causes a viscous resistance due to the movement of the chain in the electrically insulating medium, which causes a sound wave. Loss of energy (dissipation) occurs.

That is, the sound wave incident on the electrode plate causes the ENC fluid composition containing the chain to resonate with the electrode plate.
The sound wave frequency that gives vibration to such a chain is determined by the characteristic frequency of the chain (which is presumed to be the so-called natural frequency, which is the balance between the elasticity of the chain and the inertia of the electrode plate). When a sound wave having a frequency matching the characteristic frequency is incident on the electrode plate, the chain resonates to absorb and control the sound wave, and sound waves of other frequencies are reflected. The attractive force acting on each particle (stress generated in the chain) increases as the voltage applied to the pair of electrode plates increases, so the elastic modulus and viscosity of the chain itself increase with the applied voltage. Therefore, the present invention utilizes this fact. In other words, by adjusting the applied voltage so that the characteristic frequency of the chain itself matches the frequency of the component of the incident sound wave (air vibration) that you want to remove, the chain resonates and absorbs sound. It consumes the energy of the component to be (removed) and reflects the other components.

FIG. 9 is a graph showing the results of measurement of the effect of electric field strength on the EA characteristics for a 30 wt% EA particle dispersion system. It is clear from this graph that the stress acting on the chain increases as the applied voltage increases. The EA characteristic is due to the fact that the dielectrically polarized particles are arranged in the direction of the electric field by an electric attraction and form a chain structure. At low shear rates, electrical attraction dominates, resulting in a gradual cycle of breaking and reforming chain structures. The yield stress is the force that is generated when a chain arranged in the direction of the electric field undergoes shear failure in the direction perpendicular to it. Considering that the particles of all chains formed have the same diameter and connect the electrode plates in a straight line, the number of chains is proportional to the particle concentration, so the yield stress is also proportional to the particle concentration. It will be. FIG. 10 shows an equivalent circuit of the vibration system, that is, a coil spring 22 having an elastic modulus K and a dashpot 23 having a viscosity C are connected in parallel between a pair of electrode plates.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the copying machine of the present invention will be described below with reference to FIGS. Reference numeral 30 in the figure denotes the main body of the copying machine of this embodiment. In the copying machine main body 30, as shown in FIG. 1, a thin plate-shaped sound wave absorption control device 32 is fixed to an inner wall surface of an exterior plate 31. This sound wave absorption control device 32
Is configured by accommodating an ENC fluid composition (see FIG. 5) in which solid particles 2 having an electric field arranging effect are contained in an electrically insulating medium 1, and a voltage applying means for applying a voltage to the ENC fluid composition. Is connected to the variable power source 13.
The variable power supply 13 is connected to a frequency analysis device 35 that analyzes the frequency of noise detected by a microphone 34 installed inside the exterior plate 31 and sends an analysis signal to the variable power supply 13.

Next, the ENC fluid composition constituting the sound wave absorption control device 32 will be described. In FIG. 5, EN
One example of a C-fluid composition is shown. This ENC fluid composition has EA which is solid particles in the electrically insulating medium 1.
The particles 2 are uniformly dispersed. This EA particle 2
Is formed by a core body 3 made of an organic polymer compound and a surface layer 5 made of particles 4 which are electric field aligning inorganic substances (hereinafter, referred to as “EA inorganic substance”) to form inorganic / organic composite particles. . In this specific example, the electrically insulating medium 1 is colorless and transparent silicone oil, the organic polymer compound forming the core body 3 of the inorganic / organic composite particles is polyacrylic ester, and the EA inorganic substance forming the surface layer 5 is used. The particles 4 are white titanium hydroxide that is an inorganic ion exchanger and an electric semiconductor inorganic substance. The color of the EA particles (inorganic / organic composite particles) is, for example, white. The proportion of the EA particles 2 contained in the electrically insulating medium 1 is, for example, 7.5% by weight.

As shown in FIG. 6, this ENC fluid composition is interposed between a pair of electrode plates 7 and 8 which are spaced apart and arranged in parallel. As shown in FIG. 7, the pair of electrode plates 7,
When a voltage is applied to the power source 8 from the power source 9 through the switch 10, the EA particles 2 are arranged in a chain in a direction perpendicular to the surfaces of the electrode plates 7 and 8 due to the EA effect to form a chain body (particle chain) 6. Form. At this time, the chain-like bodies 6 are separated from each other and oriented in parallel.

Next, a description will be given of a sound wave absorption control device (sound control device) of the present invention using the above ENC fluid composition. As shown in FIG. 3, a pair of electrode plates 17 and 18 are opposed to each other with a gap (composition storage space) therebetween, and between the pair of electrode plates 17 and 18, the above-mentioned E of the present invention is provided.
An ENC fluid composition containing EA particles 2 having an A effect in an electrically insulating medium 1 is contained. One (lower) electrode plate 18 is fixedly arranged on a fixing member (not shown), and the other electrode plate 17 is evenly adhered to the lower surface of a PET (polyethylene terephthalate) film 17a which is flexible against sound waves. ing. A frame-shaped seal member 15 is fixed to the peripheral edges of the pair of electrode plates 17 and 18 and the PET film 17a.

A pair of electrode plates 17, 18 and a seal member 1
The ENC fluid composition of the present invention is housed in the space formed by 5 in a sealed state. The one electrode plate 17 and the PET film 17a have their peripheral edges fixed, but are configured so that they can vibrate in a direction in which the pair of electrode plates 17 and 18 face each other (the vertical direction indicated by the arrow X). Thereby, when the sound wave (air vibration) 11 is incident on the PET film 17a, the PET film 17a and the one electrode plate 17 can vertically vibrate.

The variable power source 13 includes a pair of electrode plates 17 and 18
Applying a voltage between them and adjusting the applied voltage,
A switch 14 is connected in series to the power supply 13. By turning on the switch 14, a voltage can be applied between the pair of electrode plates 17 and 18. The sound wave absorption control device is usually in the form of a rectangular plate or a circular plate in appearance, but of course, it has an appropriate shape according to the place where it is installed.

Next, the operation of the sound wave absorption control device having the above construction will be described. As shown in FIG. 3, a pair of electrode plates 1
When no voltage is applied between 7 and 18, ENC
The EA particles 2 of the fluid composition are randomly suspended and dispersed in the electrically insulating medium 1 (see FIG. 6). A pair of electrode plates 1
When a voltage is applied to 7, 18, E in the ENC fluid composition
The A particles 2 are arranged and linked in a chain to form a chain (particle chain) 6, and the chain 6 is arranged parallel to the electric field direction (see FIG. 7).

In this state, when a sound wave (air vibration) 11 is made incident on one of the electrode plates 17, (a), (b) of FIG.
The states of (c) and (d) occur sequentially, and this electrode plate 1
7 vibrates in the opposite direction together with the PET film 17a as shown by an arrow X (see FIGS. 3 and 4), but the chain-like body 6
Since the chain body 6 itself has elasticity, as shown in FIG. 8 (b), when it is compressed, the chain body 6 bends in a V shape, for example, to generate a repulsive force, As shown in (d) of FIG. 8, when the chain-shaped body 6 is pulled, the EA particles 2 facing each other attract each other to generate an attractive force. As a result, the movement of the chain 6 in the ENC fluid composition causes
Viscous resistance occurs, and the energy of the sound wave 11 is lost (dissipated).

As the electrode plate 17 vibrates,
The chain 6 is repeatedly pulled and compressed,
As a result, the chain body 6 itself also vibrates. That is, the sound wave 11 incident on the electrode plate 17, the ENC fluid composition containing the chain body 6, the electrode plate 17 and the PET film 17
The electrode plate structure composed of a resonates. The sound wave frequency that gives vibration to the chain 6 is as follows.
When the sound wave 11 having a frequency matching with the characteristic frequency of the light enters the electrode plate 17, the chain 6 resonates (see arrows A and B in FIG. 4) to absorb the sound wave. Controlling, the sound waves 12 of other frequencies will be reflected.

The force acting between the EA particles 2 (stress generated in the chain 6) increases as the voltage applied to the pair of electrode plates 17 and 18 increases, so that the elasticity of the chain 6 itself. The modulus and viscosity increase with increasing applied voltage. The present invention utilizes this fact to remove a desired component of a sound wave. That is, by adjusting the applied voltage,
By matching the characteristic frequency of the particle chain 6 itself with the frequency of the component (sound wave having a specific wavelength) to be removed from the sound wave (air vibration) incident on the electrode plate 17, as shown in FIG. The body 6 is caused to resonate by the action of the inertial force as indicated by the left and right arrows A and B, and the energy of the component of the incident sound wave 11 to be removed is consumed, while the other sound wave components (reference numeral 1) are consumed.
2) is reflected. In this way, the applied voltage absorbs and absorbs the component of the desired specific wavelength of the incident sound wave.
You can control.

The characteristic frequency of the sound wave absorption control device changes depending on the size of the EA particles (solid particles), the elastic force acting between the EA particles, the natural frequency of the electrode plates and the distance between the electrode plates. In this example, since spherical EA particles having a substantially uniform particle size were dispersed in the electrically insulating medium (without using irregular particles), the above-mentioned repulsive force and attractive force were not generated under a constant voltage. It does not fluctuate, and furthermore, the balance between the elastic force acting between the EA particles and the inertial force of the electrode plate does not fluctuate easily. In the above-mentioned embodiment, the chain body is supposed to be bent in a V shape, but in addition to this, for example, an S-shape as shown in FIG. 11A, or (b) in FIG. ) W as shown in
It is considered that there is a case where it is bent into a letter shape.

In the above embodiment, the phenomenon in which the EA particles (inorganic / organic composite particles) 2 form a row of chain-like bodies 6 and are arranged in parallel by the application of an electric field has been described. When the number of slabs exceeds several% by weight, 1
Instead of the chained bodies 6 in a row, the chained bodies 6 are joined to each other in a plurality of rows to form a column 19 as shown in FIG. In this column 19, the left and right chain-shaped EA particles 2 are staggered by one and adjoin each other. With respect to this, the inventors of the present invention, as shown in (b) of FIG. 12, have the EA particles 2 that are dielectrically polarized in the + pole portion and the − pole portion.
It is presumed that this is because it is more stable in terms of energy when the positive pole portion and the negative pole portion are alternately arranged adjacent to each other. Further, in the above-mentioned Examples, the one in which the ENC fluid composition was directly accommodated between the pair of electrode plates was shown, but the present invention is not limited to this, and the porous body sufficiently impregnated with the ENC fluid composition is provided in the pair of electrodes. It may be housed between the plates. In this case, the porous body preferably has open cells so as not to impair the EA effect.

Examples of the electrically insulating medium 1 used in the ENC fluid composition of the present invention include diphenyl chloride, butyl sebacate, aromatic polycarboxylic acid higher alcohol ester, halophenyl alkyl ether, trans oil, chlorinated paraffin, and fluorine. Any fluid or mixture thereof, such as a system oil, a silicone oil or a fluorosilicone oil, as long as it has high electric insulation and electric breakdown strength, is chemically stable, and can stably disperse EA particles. Can also be used. This electrically insulating medium 1 can be colored according to the purpose. For coloring, it is preferable to use a type and amount of an oil-soluble dye or a dispersible dye that is soluble in the selected electrically insulating medium and does not impair its electrical properties. The electrically insulating medium 1 may further contain a dispersant, a surfactant, a viscosity modifier, an antioxidant, a stabilizer and the like.

The kinematic viscosity of this electrically insulating medium 1 is 1 cS.
It is preferably in the range of t to 30,000 cSt. When the kinematic viscosity is less than 1 cSt, the storage stability of the ENC fluid composition is insufficient, and the kinematic viscosity is 30,000 c.
If it is larger than St, it becomes difficult to uniformly disperse the EA particles, and it becomes difficult for the bubbles to be caught during the adjustment, and the bubbles will not come out easily, which is not preferable. From this viewpoint, the kinematic viscosity is preferably in the range of 10 cSt to 1000 cSt, particularly preferably in the range of 10 cSt to 100 cSt. Of course, the kinematic viscosity of the electrically insulating medium 1 changes with temperature, and this temperature effect can be suppressed by the applied voltage.

The EA particles 2 used in the present invention are, if they are inorganic / organic composite particles having an EA effect, an element, an organic compound, an inorganic compound, or a mixture thereof.
Either material can be used. Examples thereof include particles of inorganic ion exchangers, metal oxides, silica gel, inorganic substances having electric semiconductors, carbon black, and particles having these as a surface layer. However, as shown in the above-mentioned examples, the EA particles 2 include the core body 3 made of an organic polymer compound and the particles 4 of the EA inorganic material.
It is particularly preferable that the inorganic-organic composite particles are formed by the surface layer 5 consisting of. In this inorganic-organic composite particle, a surface layer 5 composed of particles 4 of EA inorganic material having a relatively high specific gravity is carried on a core body 3 which is an organic polymer compound having a relatively low specific gravity, and the specific gravity of the entire particle is changed to an electric value. It can be adjusted to approximate the insulating medium 1. Therefore, the ENC fluid composition obtained by dispersing this in the electrically insulating medium 1 has excellent storage stability.

Examples of the organic polymer compound which can be used as the core 3 of the EA particles (inorganic / organic composite particles) 2 are poly (meth) acrylic acid ester, (meth) acrylic acid ester-styrene copolymer, Polystyrene, polyethylene, polypropylene, nitrile rubber, butyl rubber, AB
S resin, nylon, polyvinyl butyrate, ionomer, ethylene-vinyl acetate copolymer, vinyl acetate resin,
One or a mixture of two or more such as a polycarbonate resin or a copolymer may be mentioned.

Particles 4 which are the EA inorganic substance forming the surface layer 5
Although various compounds can be used, preferred examples include inorganic ion exchangers, silica gel, and electrically semiconducting inorganic substances. When these particles 4 are used to form the surface layer 5 on the core 3 made of an organic polymer compound, the obtained inorganic / organic composite particles become useful EA particles 2.

Examples of the inorganic ion exchanger include (1)
Hydroxide of polyvalent metal, (2) hydrotalcites,
(3) Acid salt of polyvalent metal, (4) Hydroxyapatite, (5) Nasicon type compound, (6) Clay mineral, (7)
Mention may be made of potassium titanates, (8) heteropolyacid salts, and (9) insoluble ferrocyanide.

The respective inorganic ion exchangers will be described in detail below. (1) Hydroxide of polyvalent metal. These compounds are represented by the general formula MO _x (OH) _y (M is a polyvalent metal, x is a number of 0 or more, and y is a positive number), and examples thereof include titanium hydroxide and hydroxide. zirconium,
Examples thereof include bismuth hydroxide, tin hydroxide, lead hydroxide, aluminum hydroxide, tantalum hydroxide, niobium hydroxide, molybdenum hydroxide, magnesium hydroxide, manganese hydroxide and iron hydroxide. Here, for example, titanium hydroxide refers to hydrous titanium oxide (also known as metatitanic acid or β-titanic acid, TiO 2
(OH) ₂ ) and titanium hydroxide (also known as orthotitanic acid or α-titanic acid, Ti (OH) ₄ ) are included, and the same applies to other compounds.

(2) Hydrotalcites. These compounds have the general formula M ₁₃ Al ₆ (OH) ₄₃ (C
O) ₃ · 12H ₂ O (M is a divalent metal),
For example, the divalent metal M is Mg, Ca or Ni. (3) Acid salt of polyvalent metal. These are, for example, titanium phosphate, zirconium phosphate, tin phosphate, cerium phosphate, chromium phosphate, zirconium arsenate, titanium arsenate, tin arsenate, cerium arsenate, titanium antimonate, tin antimonate, tantalum antimonate. , Niobium antimonate, zirconium tungstate, titanium vanadate, zirconium molybdate, titanium selenate, and tin molybdate.

(4) Hydroxyapatite. These are, for example, calcium apatite, lead apatite,
Examples include strontium apatite and cadmium apatite. (5) Nasicon type compound. These include, for example, (H ₃ O) Zr ₂ (PO ₄ ) ₃ but in the present invention, a Nasicon type compound in which H ₃ O is replaced with Na can also be used. (6) Clay mineral. These are, for example, montmorillonite, sepiolite, bentonite and the like, with sepiolite being particularly preferred.

(7) Potassium titanates. These general formula _{aK 2 O · bTiO 2 · nH} 2 O (a 0
<A is a positive number that satisfies a ≦ 1, b is a positive number that satisfies 1 ≦ b ≦ 6, and n is a positive number), for example, K ₂ ·
TiO ₂ · 2H ₂ O, K ₂ O · 2TiO ₂ · 2H ₂ O, 0.
5K ₂ O ・ TiO ₂・ 2H ₂ O, and K ₂ O ・ 2.5TiO
₂ · 2H ₂ O, and the like. Incidentally, among the above compounds, a compound in which a or b is not an integer can be easily synthesized by acid-treating a compound in which a or b is an appropriate integer and replacing K with H.

(8) Heteropolyacid salt. These are represented by the general formula H ₃ AE ₁₂ O ₄₀ .nH ₂ O (A is phosphorus, arsenic, germanium, or silicon, E is molybdenum, tungsten, or vanadium, and n is a positive number), For example, ammonium molybdophosphate and ammonium tungstophosphate. (9) Insoluble ferrocyanide. These are compounds represented by the following general formula. M _b-pxa
A [E (CN) ₆ ] (M is an alkali metal or hydrogen ion, A is a heavy metal ion such as zinc, copper, nickel, cobalt, manganese, cadmium, iron (III) or titanium, E is iron (II), iron (III), cobalt (II) or the like, b is 4 or 3, a is a valence of A, and p is a positive number of 0 to b / a.) These include, for example, Cs. ₂ Zn [Fe (CN) ₆ ] and K
₂ Insoluble ferrocyanine compounds such as Co [Fe (CN) ₆ ] are included.

The inorganic ion exchangers (1) to (6) each have an OH group, and some or all of the ions present at the ion exchange sites of these inorganic ion exchangers are different from other ions. Those substituted with (hereinafter, referred to as a substitutional inorganic ion exchanger) are also included in the inorganic ion exchanger of the present invention. That, R-M ¹ inorganic ion exchanger described above (M ¹ represents an ion species of the ion exchange sites) is expressed as a part or all of M ¹ in the R-M ^1, the ion exchange reaction below A substituted inorganic ion exchanger in which an ionic species M ² different from M ¹ is substituted by
It is an inorganic ion exchanger in the present invention. xR−M ¹ + yM ² → Rx− (M ² ) y + xM ¹ (where x and y represent the valences of the ion species M ² and M ¹ , respectively). M ¹ varies depending on the type of the inorganic ion exchanger having an OH group, but when the inorganic ion exchanger exhibits a cation exchange property, M ¹ is generally H ⁺ , and in this case, M ² is an alkali metal or an alkali. Any metal ion other than H ⁺ , such as earth metals, polyvalent typical metals, transition metals or rare earth metals. When the inorganic ion exchanger having an OH group exhibits anion exchange property, M ¹ is generally OH ^−.
Where M ² is, for example, I, Cl, SCN, N
Any of anions other than OH ⁻ such as O ₂ , Br, F, CH ₃ COO, SO ₄ or CrO ₄ and complex ions.

Further, regarding the inorganic ion exchanger which has once lost the OH group due to the high temperature heat treatment but becomes to have the OH group again by an operation such as immersion in water, the inorganic ion after the high temperature heat treatment is used. Exchangers and the like are also a kind of inorganic ion exchangers that can be used in the present invention, and specific examples thereof include a Nasicon type compound such as (H ₃ O) Zr ₂
(PO ₄₎ HZr ₂ obtained by heating ₃ (PO _{4) 3} and high-temperature heat treatment of hydrotalcite (500 to 700
Heat treatment at ℃) etc. These inorganic ion exchangers can be used not only in one kind but also in many kinds simultaneously as a surface layer. In addition, it is particularly preferable to use a hydroxide of a polyvalent metal and an acid salt of a polyvalent metal as the inorganic ion exchanger.

An example of an electrically semiconductive inorganic material that can be used as the surface layer 5 of the EA particles (inorganic / organic composite particles) 2 is a metal having an electric conductivity of 10 ³ to 10 ^-11 Ω ^-1 / cm at room temperature. Oxides, metal hydroxides, metal oxide hydroxides, inorganic ion exchangers, or metal-doped at least one of these, or at least any one of these regardless of the presence or absence of metal doping For example, those applied as an electric semiconductor layer on another support.

Examples of preferable electrically semiconductive inorganic substances are shown below. (A) Metal oxide: For example, SnO ₂ or amorphous titanium dioxide (manufactured by Idemitsu Petrochemical Co., Ltd.). (B) Metal hydroxide: For example, titanium hydroxide or niobium hydroxide. Here, titanium hydroxide means hydrous titanium oxide (manufactured by Ishihara Sangyo Co., Ltd.), metatitanic acid (also known as β-titanic acid,
TiO (OH) ₂ ) and orthotitanic acid (also known as α-titanic acid, Ti (OH) ₄ ) are included. (C) Metal oxide hydroxide: For example, FeO
(OH) (goethite) and the like can be mentioned. (D) Hydroxide of polyvalent metal: equivalent to inorganic ion exchanger (1). (E) Hydrotalcites: Inorganic ion exchanger (2)
Equivalent to (F) Acid salt of polyvalent metal: equivalent to the inorganic ion exchanger (3). (G) Hydroxyapatite: Inorganic ion exchanger (4)
Equivalent to (H) Nashicon type compound: equivalent to the inorganic ion exchanger (5). (I) Clay mineral: equivalent to the inorganic ion exchanger (6). (J) Potassium titanate: equivalent to the inorganic ion exchanger (7). (K) Heteropolyacid salt: equivalent to the inorganic ion exchanger (8). (L) Insoluble ferrocyanide: equivalent to inorganic ion exchanger (9). (M) Metal-Doped Electric Field Alignment Inorganic Material: This is an ER inorganic material doped with a metal such as antimony (Sb) in order to increase the electric conductivity of the above-mentioned electric semiconductor inorganic materials (A) to (L). As an example, antimony (Sb) -doped tin oxide (SnO ₂ ) and the like can be mentioned. (N) EA inorganic material applied as an electric semiconductor layer on another support: for example, titanium oxide, silica as a support,
Examples thereof include inorganic particles such as alumina and silica-alumina, or organic polymer particles such as polyethylene and polypropylene, to which antimony (Sb) -doped tin oxide (SnO ₂ ) is applied as an electric semiconductor layer. . The particles in which the EA inorganic substance is applied to the other support as described above can be regarded as the EA inorganic substance as a whole. These EA minerals are not only one type, but two
It is also possible to use types or more simultaneously as the surface layer.

The EA particles (inorganic / organic composite particles) 2 can be manufactured by various methods. For example, there is a method in which a particulate core body 3 made of an organic polymer compound and fine particulate particles 4 are transported by a jet stream and collided with each other to produce them. In this case, the fine particles of the particles 4 collide with the surface of the particulate core 3 at a high speed and are fixed to form the surface layer 5. Another example of the manufacturing method is a method in which the particulate core body 3 is suspended in a gas, and a solution of the particles 4 is atomized and sprayed on the surface. In this case, the surface layer 5 is formed by adhering the solution onto the surface of the core 3 and drying it.

A particularly preferred method for producing the EA particles (inorganic / organic composite particles) 2 is to form the surface layer 5 at the same time as the core body 3. In this method, for example, when emulsion-polymerizing, suspension-polymerizing, or dispersion-polymerizing the monomer of the organic polymer compound forming the core body 3 in a polymerization medium, the particles 4 which are fine particle EA inorganic substances in the monomer are Alternatively, it is present in the polymerization medium. Water is preferred as the polymerization medium, but a mixture of water and a water-soluble organic solvent can also be used, and an organic poor solvent can also be used. According to this method, the monomers are polymerized in the polymerization medium to form the core particles 3, and at the same time, the fine particle EA inorganic particles 4 are layered on the surface of the core 3 to cover the core particles 3. The surface layer 5 is formed.

When EA particles (inorganic / organic composite particles) are produced by emulsion polymerization or suspension polymerization, the EA inorganic particles 4 are combined by combining the hydrophobic property of the monomer and the hydrophilic property of the EA inorganic substance. Can be attached to the surface of the core body 3. According to the method of simultaneously forming the core body 3 and the surface layer 5, the EA inorganic particles 4 are densely and firmly adhered to the surface of the core body 3 made of an organic polymer compound, and the EA particles (inorganic / organic composite) Particles 2) are formed.

The shape of the EA particles 2 used in the present invention does not necessarily have to be spherical, but when the particulate core 3 is produced by a controlled emulsion / suspension polymerization method, the EA obtained is obtained. The shape of the particles 2 is almost spherical. EA
The particle size of the particles 2 is not particularly limited, but is 0.1
The thickness is preferably in the range of μm to 500 μm, particularly 5 μm to 200 μm. Fine particle EA at this time
The particle size of the inorganic particles 4 is not particularly limited, but is preferably 0.005 μm to 100 μm, and more preferably 0.01 μm to 10 μm.

In the EA particle (inorganic / organic composite particle) 2, the particle 4 and the core 3 which are the EA inorganic substance forming the surface layer 5 are formed.
The weight ratio of the organic polymer compound forming the is not particularly limited, but in order to obtain an ENC fluid composition having high storage stability, the EA inorganic particles 4 and the organic polymer compound core 3 are used. 1% by weight of particles 4 to 6% of the total weight
It is preferably in the range of 0% by weight, particularly preferably in the range of 4% by weight to 30% by weight. If the proportion of the core 3 is less than 1% by weight, the EA characteristics of the obtained EA particles 2 will be insufficient, and if it exceeds 60% by weight, the specific gravity of the EA2 particles will be excessive and the storage stability may be impaired. There is. The ENC fluid composition of the present invention can be produced by uniformly stirring and mixing the EA particles 2 together with a dispersant and other components in an electrically insulating medium, if necessary. As the stirrer, any stirrer normally used for dispersing solid particles in a liquid dispersion medium can be used. In an electrically insulating medium 1
The content of the EA particles 2 in is not particularly limited, but is preferably 0.5 to 75% by weight, and particularly preferably 5 to 50% by weight. If the content is less than 1%, a sufficient EA effect cannot be obtained, and if the content is 75% or more, the initial viscosity of the ENC fluid composition when a voltage is not applied becomes too large, which makes it difficult to use.

The EA particles 2 produced by the above-mentioned various methods, particularly the method of simultaneously forming the core 3 and the surface layer 5,
The whole or part of the surface layer 5 may be covered with a thin film of an organic polymer substance, a dispersant used in the manufacturing process, an emulsifier or other additive substances, and the EA effect as EA particles may not be sufficiently exhibited. . This thin film of inert material can be easily removed by polishing the surface of the particles. Therefore, when the core body 3 and the surface layer 5 are simultaneously formed, it is preferable to polish the surfaces thereof.

The surface of the particles can be polished by various methods. For example, EA, which is an inorganic / organic composite particle
The method can be performed by dispersing the particles 2 in a dispersion medium such as water and stirring this. At this time, a method of mixing an abrasive such as sand particles or balls into the dispersion medium and stirring with the EA particles 2, a method of stirring with a grinding wheel, or the like can be used. For example, it is also possible to carry out dry stirring without using a dispersion medium, using the EA particles 2 and the above-mentioned abrasive or grinding stone.

A more preferable polishing method is a method in which the EA particles 2 are agitated by a jet stream or the like. This is a method of polishing particles by violently colliding with each other in a gas phase, and is a preferable method in that the polished particles can be easily separated by classification without the need for another abrasive. In the above jet stream agitation, it is necessary to select polishing conditions depending on the type of equipment used, the agitation speed, the material of the EA particles 2, etc., but generally 60
It is preferable to perform jet stream stirring at a stirring speed of 00 rpm for about 0.5 min to 15 min.

The ENC fluid composition of the present invention comprises the above EA
The particles 2 can be produced by uniformly stirring and mixing them in the electrically insulating medium 1 together with other components such as a dispersant, if necessary. As the stirrer, any stirrer normally used for dispersing solid particles in a liquid dispersion medium can be used.

In the copying machine main body 30, as shown in FIG. 2, when the microphone 34 detects noise, the frequency analysis device 35 detects the noise, and based on the noise detection signal, the high-level frequency band of the detected noise is detected. Is analyzed and an analysis signal is transmitted to the variable power source 13. The variable power supply 13 that receives the analysis signal determines the sound absorption frequency of the sound wave absorption control device 32 as the frequency analysis device 3
A voltage is applied to the sound wave absorption control device 32 so as to match the high level band of the noise analyzed in 5. By doing so, the sound absorption frequency of the sound wave absorption control device 32 can be changed to follow the frequency of the noise even when the rotational frequency of the drive motor 36 and the operating portion of the internal device 37 change and the high level band of the noise changes. Therefore, the noise can always be efficiently absorbed. Moreover, the sound wave absorption control device 32
Has a high reaction speed with respect to the applied voltage of the ENC fluid composition, so that the sound absorption frequency can be changed in real time in response to the change in the high level band of noise.
Even if the high-level band of noise changes frequently in a short time, no sound absorption time is generated.

Therefore, according to the copying machine main body 30 of the present invention, it is possible to constantly absorb sound with high efficiency in response to the change in the high level band of noise, and also the sound absorption control device 3 in the form of a thin plate.
By using 2, it is not necessary to secure an installation space in the exterior plate 31, so that it can be formed with low noise and small size.

The microphone 34 may be installed outside the exterior plate 31. In this case, the exterior plate 31
Since the sound insulation performance inside and outside is not so high, these noises can be efficiently absorbed by the sound wave absorption control device 32 corresponding to the high level band of the noise of the copying machine main body 30 and its surroundings detected by the microphone 34. , Can improve the environment in the office.

[0050]

As described above, according to the copying machine of the present invention, the copying machine main body having the copying function is provided with the sound wave absorption control device for absorbing and controlling the noise generated from the copying machine main body. The sound wave absorption control device contains an ENC fluid composition in which EA particles having an electric field array effect are contained in an electrically insulating medium.
It is connected to a voltage applying means for applying a voltage to the fluid composition and adjusting the applied voltage, and adjusts the applied voltage in accordance with a high level band of noise, so that it is possible to absorb sound with high efficiency at all times, and also a sound wave absorption control device Since it can be formed into a thin plate, it is not necessary to secure an installation space for the sound wave absorption control device in the exterior plate, and it can be formed with low noise and small size.

[Brief description of drawings]

FIG. 1 is a sectional view illustrating an embodiment of a copying machine of the present invention.

FIG. 2 is a block diagram illustrating the operation of an embodiment of a copying machine of the present invention.

FIG. 3 is a cross-sectional view of a sound wave absorption control device (sound control device) provided with the electro-sensitive sound wave absorption control fluid composition.

FIG. 4 is a cross-sectional view showing a state in which a chain and one electrode plate resonate upon incidence of a sound wave in the sound wave absorption control device.

FIG. 5 is a cross-sectional view showing an example of the electro-sensitive acoustic wave absorption controlling fluid composition according to the present invention.

FIG. 6 is a cross-sectional view showing an aspect of the fluid composition for electro-sensitive sound wave absorption control according to the present invention when the power is off.

FIG. 7 is a cross-sectional view showing an aspect of the fluid composition for electro-sensitive sound wave absorption control according to the present invention when the power is turned on.

FIG. 8 is a cross-sectional view showing a state where a sound wave is incident on the sound wave absorption control device and one of the electrode plates vibrates.

FIG. 9 is a graph showing the results of measuring the effect of electric field strength on electric field arrangement characteristics of an electric field arrangement particle dispersion system.

FIG. 10 is a diagram showing an equivalent circuit of a vibration system.

FIG. 11 is a diagram showing another example of the bending state of the chain-like body in the sound wave absorption control device.

FIG. 12 is a view showing a column in which a plurality of chains are joined to each other in the sound wave absorption control device.

13A and 13B are views showing a conventional copying machine, in which FIG. 13A is a partially cutaway front view and FIG. 13B is a side sectional view.

[Explanation of symbols]

1 ... Electrically insulating medium, 2 ... EA particles (solid particles), 9 ...
Variable power source (voltage applying means), 13 ... Variable power source (voltage applying means), 30 ... Copier body, 32 ... Sound wave absorption control device.

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Kazuya Edamura 2-6-15 Shiba Park, Minato-ku, Tokyo Inside Fujikura Kasei Co., Ltd. (72) Inventor Hidenobu Anzai 1-5 Kiba, Koto-ku, Tokyo No. 1 Fujikura Co., Ltd. (72) Inventor Yasufumi Otsubo 9-21-1 Konakadai, Inage-ku, Chiba-shi, Chiba 206

Claims (1)

[Claims] 1. A copying machine body (30) having a copying function.
And a sound wave absorption control device (32) for absorbing and controlling noise generated from the main body of the copying machine, wherein the sound wave absorption control device has solid particles (2) having an electric field array effect as an electrically insulating medium. (1) A fluid composition for electro-sensitive sound wave absorption control contained in (1) is accommodated, and a voltage is applied to the electro-sensitive sound wave absorption control fluid composition and to adjust the applied voltage. Means (9, 1
A copying machine characterized by being connected to 3).