Patent Application
20210315349
The present disclosure relates to a discharge device and a hair care device including the discharge device. In particular, the present disclosure relates to a discharge device including a discharge electrode and a counter electrode, and a hair care device including the discharge device.
Conventionally, an electrostatic atomizer that produces charged fine particle water is known (see, for example, PTL 1). The electrostatic atomizer disclosed in PTL 1 includes a discharge electrode having a tip and a counter electrode located to face the tip. The electrostatic atomizer supplies water to the discharge electrode and applies a voltage, thereby generating charged fine particle water using the water supplied to the discharge electrode. The charged fine particle water contains an active ingredient such as a radical.
When the electrostatic atomizer (discharge device) disclosed in PTL 1 is applied to, for example, a hair dryer, it is desired to generate charged fine particle water containing large amounts of acidic components such as nitrate ions and nitrogen oxides.
PTL 1: Unexamined Japanese Patent Publication No. 2014-231047
The present disclosure provides a discharge device and a hair care device capable of increasing a produced amount of acidic components.
The discharge device according to one aspect of the present disclosure includes a discharge electrode, a counter electrode, and a voltage application unit. The counter electrode faces the discharge electrode in a first direction. The voltage application unit generates a discharge by applying an application voltage between the discharge electrode and the counter electrode. The counter electrode includes a dome-shaped electrode and a protruding electrode. The dome-shaped electrode has a recessed inner surface that is recessed to a side opposite to the discharge electrode in the first direction. The protruding electrode protrudes in a second direction intersecting the first direction from an opening edge of an opening of the dome-shaped electrode, the opening being provided at an end opposite to the discharge electrode. When a discharge occurs, the discharge device forms a discharge path having at least partial dielectric breakdown between the discharge electrode and the protruding electrode. The discharge path includes a first dielectric breakdown region and a second dielectric breakdown region. The first dielectric breakdown region is generated around the discharge electrode. The second dielectric breakdown region is generated around the protruding electrode.
The hair care device according to one aspect of the present disclosure includes the abovementioned discharge device and an airflow generator that generates an airflow with respect to the discharge device.
According to the present disclosure, it is possible to achieve a discharge device and a hair care device capable of increasing a produced amount of acidic components.
An exemplary embodiment and modifications described below are merely examples of the present disclosure. The present disclosure is not limited to the exemplary embodiment and modifications, and besides the following exemplary embodiment and modifications, various changes are possible depending on design or the like without departing from the scope of the technical idea of the present disclosure. Drawings used in the following exemplary embodiment and modifications are schematic, and a dimensional ratio or thickness ratio of components in the drawings may not reflect an actual dimensional ratio.
A discharge device and a hair care device according to the present exemplary embodiment will be described below separately for each item.
An overview of discharge device 10 and hair care device 100 according to the present exemplary embodiment will now be described with reference to
In the following description, a lateral direction of discharge device 10 is defined as an X-axis direction (or a second direction), a front-rear direction is defined as a Y-axis direction (or a first direction), and a vertical direction is defined as a Z-axis direction. Further, the rightward direction of discharge device 10 is defined as the positive direction of the X-axis, and the leftward direction is defined as the negative direction of the X-axis. Further, the forward direction of discharge device 10 is defined as the positive direction of the Y-axis, and the rearward direction is defined as the negative direction of the Y-axis. Further, the upward direction of discharge device 10 is defined as the positive direction of the Z-axis, and the downward direction is defined as the negative direction of the Z-axis.
As shown in
In the present exemplary embodiment, counter electrode 2 includes, for example, a pair of protruding electrodes 23 as shown in
As shown in
Notably, it is sufficient that discharge device 10 includes, as minimum components, discharge electrode 1, counter electrode 2, and voltage application unit 3. Therefore, liquid supply unit 4 may not be included in the components of discharge device 10.
Further, as shown in
Further, in discharge device 10, a voltage is applied by voltage application unit 3 between discharge electrode 1 and counter electrode 2, while, for example, liquid 40 is adhered to and retained on the surface of discharge electrode 1. As a result, a discharge is generated between discharge electrode 1 and counter electrode 2, so that liquid 40 retained on discharge electrode 1 is electrostatically atomized by the discharge. In other words, discharge device 10 according to the present exemplary embodiment constitutes a so-called electrostatic atomizer. Here, in the present disclosure, liquid 40 retained on discharge electrode 1, that is, liquid 40 to be electrostatically atomized, may be simply referred to as “liquid 40”.
As shown in
As will be described in detail later, due to application of a voltage (application voltage) between discharge electrode 1 and counter electrode 2, liquid 40 retained on discharge electrode 1 is formed into a conical shape called a Taylor cone by receiving force due to an electric field as shown in
Further, liquid 40 retained on discharge electrode 1 is alternately deformed into a first shape and a second shape by the mechanical vibration. The first shape indicates the shape of the Taylor cone shown in
Further, in discharge device 10, discharge electrode 1 and protruding electrode 23 of counter electrode 2 are disposed to face each other with a gap therebetween in the first direction (Y-axis direction). Then, when the application voltage is applied between discharge electrode 1 and protruding electrode 23 of counter electrode 2 by voltage application unit 3, a discharge is generated. At this time, when a discharge occurs, discharge path 200 (see
The “dielectric breakdown” described in the present disclosure means that electrical insulation of an insulator (including gas) separating conductors is broken, and the insulating state cannot be maintained. Specifically, in a case of dielectric breakdown of a gas, for example, ionized molecules are accelerated by an electric field and collide with other gas molecules to be ionized. Then, the ion concentration suddenly increases to cause a gas discharge, so that dielectric breakdown occurs. That is, in discharge device 10 according to the present exemplary embodiment, when a discharge occurs, the gas (air) present in the path connecting discharge electrode 1 and protruding electrodes 23 has dielectric breakdown locally, that is, only in a part thereof. Thus, discharge path 200 formed between discharge electrode 1 and protruding electrode 23 does not reach entire dielectric breakdown, but only has partial dielectric breakdown.
In this case, discharge path 200 includes first dielectric breakdown region 201 generated around discharge electrode 1 and second dielectric breakdown region 202 generated around protruding electrode 23 of counter electrode 2 as described above. First dielectric breakdown region 201 indicates a region where dielectric breakdown occurs around discharge electrode 1, and second dielectric breakdown region 202 indicates a region where dielectric breakdown occurs around protruding electrode 23. Then, first dielectric breakdown region 201 and second dielectric breakdown region 202 are generated in distant regions of discharge path 200 so as not to come into contact with each other. In other words, in discharge path 200, first dielectric breakdown region 201 and second dielectric breakdown region 202 are separated from each other. Therefore, discharge path 200 includes a region (insulation region) where dielectric breakdown does not occur at least between first dielectric breakdown region 201 and second dielectric breakdown region 202. Thus, discharge path 200 between discharge electrode 1 and protruding electrode 23 includes a region where dielectric breakdown occurs partially while keeping an insulation region in at least a part thereof. As a result, discharge path 200 is formed in a state where the electrical insulation is lowered.
As described above, according to discharge device 10, discharge path 200 in which dielectric breakdown occurs not entirely but partially is formed between discharge electrode 1 and protruding electrode 23 of counter electrode 2. With this configuration, even when discharge path 200 in which partial dielectric breakdown occurs, in other words, discharge path 200 including a region where dielectric breakdown does not occur in a part thereof, is used, a current flows between discharge electrode 1 and protruding electrode 23 through discharge path 200, and thus, a discharge occurs.
Note that the discharge in a mode in which discharge path 200 having partial dielectric breakdown is formed will be referred to as “partial breakdown discharge” below. The partial breakdown discharge will be described in detail in the section of “(2.4) Partial breakdown discharge”.
Here, the partial breakdown discharge generates a large amount of energy as compared with a corona discharge. Therefore, in the partial breakdown discharge, oxygen and nitrogen in the air chemically react with each other to generate an acidic component such as nitrogen oxide. When attached to, for example, skin, the generated acidic component makes the skin mildly acidic. Therefore, the acidic component accelerates, in the skin, the production of moisturizing ingredients such as natural moisturizing molecules and intercellular lipids. In other words, the acidic component has an effect of boosting the ability of the skin to retain moisture. In addition, the acidic component tightens cuticle that covers the surface of the hair. That is, the acidic component also has an effect of preventing discharge of water, nutrients, and the like from inside of the hair.
In addition, when acidic components are generated by the partial breakdown discharge, ozone is also generated simultaneously. However, discharge device 10 according to the present exemplary embodiment is configured such that an electric field is concentrated on the tip of protruding electrode 23. Therefore, a generated amount of ozone can be suppressed to the same extent as that in the corona discharge.
Further, in the partial breakdown discharge, large amounts of radicals about 2 to 10 times as much as that in the corona discharge are generated. The generated radicals are the basis for providing useful effects in various situations, besides sterilization, deodorization, moisture retention, freshness retention, and inactivation of viruses. Therefore, the generated radicals can also be effectively utilized.
On the other hand, apart from the partial breakdown discharge, there is a discharge in a mode in which a phenomenon where dielectric breakdown (entire breakdown) occurs due to development of a corona discharge is intermittently repeated. In the following description, the discharge in such a mode will be referred to as “entire breakdown discharge”.
The entire breakdown discharge occurs by an operation described below.
First, when a corona discharge develops, and dielectric breakdown (entire breakdown) occurs, a relatively large discharge current flows instantaneously. Immediately after a large discharge current flows, the application voltage drops, and the discharge current is cut off. When the discharge current is cut off, the application voltage rises again, leading to dielectric breakdown. That is, the abovementioned phenomenon is repeated in the entire breakdown discharge. In this case, even in the entire breakdown discharge, a large amount of energy is also generated as compared with the corona discharge, as in the partial breakdown discharge. Therefore, acidic components such as nitrogen oxides are generated by the entire breakdown discharge. However, the energy generated by the entire breakdown discharge is much larger than the energy generated by the partial breakdown discharge. Thus, electrolytic corrosion of the electrodes (discharge electrode 1, protruding electrodes 23) due to the energy at the time of discharge becomes larger than that in the partial breakdown discharge. Therefore, considering the life of discharge device 10, it is preferable to limit the discharge to the partial breakdown discharge.
That is, in discharge device 10 according to the present exemplary embodiment, the partial breakdown discharge or the entire breakdown discharge is caused between discharge electrode 1 and protruding electrode 23 of counter electrode 2 that face each other in the first direction with a gap therebetween. With this configuration, the produced amount of acidic components can be increased as compared with the case of the corona discharge. Further, due to the electric field being concentrated on the tip of protruding electrode 23, the generated amount of ozone can be suppressed to the same extent as that in the corona discharge.
Hereinafter, discharge device 10 and hair care device 100 according to the present exemplary embodiment will be described in detail with reference to
Hereinafter, a hair dryer shown in
As shown in
Airflow generator 20 includes, for example, a small blower fan. Airflow generator 20 generates an airflow blown out from an opening of casing 101 using the outside air introduced by the blower fan. As shown in
Casing 101 is made of a molded article formed using a synthetic resin such as ABS, and is formed in a tubular shape extending in the front-rear direction. Casing 101 is provided with vent hole 104 formed in the front surface, vent hole 104 penetrating housing 101 in the front-rear direction (Y-axis direction). Casing 101 houses inside discharge device 10, airflow generator 20, and the like. As described above, discharge device 10 generates the active ingredients (acidic components, radicals, charged fine particle water, etc.). The generated active ingredients are discharged to the outside of casing 101 through vent hole 104 by the airflow from airflow generator 20. Grip 102 is connected to a lower end of casing 101.
Similar to casing 101, grip 102 is made of a molded article formed using a synthetic resin such as ABS, and is formed in a tubular shape extending in the vertical direction. Grip 102 is connected to casing 101 so as to be movable (foldable) between a first position and a second position. The first position indicates a position in which the longitudinal direction of grip 102 is along the vertical direction (a direction intersecting the longitudinal direction of casing 101: the Z-axis direction) as shown in
As shown in
As shown in
Discharge electrode 1 is composed of, for example, a rod-shaped electrode. Discharge electrode 1 has tip 11 at one end (upper end) in the longitudinal direction (vertical direction: Y-axis direction), and base end 12 on the other end (an end opposite to the tip, a lower end) in the longitudinal direction. Discharge electrode 1 is a needle-shaped electrode in which at least tip 11 has a tapered shape. Here, the “tapered shape” is not limited to a shape having a sharp tip, but also includes a shape having a rounded tip as shown in
Counter electrode 2 is disposed at a position facing tip 11 of discharge electrode 1 in the first direction (front-rear direction: Y-axis direction). Counter electrode 2 is made of, for example, titanium. As shown in
Further, as shown in
Discharge electrode 1 and counter electrode 2 are disposed such that, as shown in
Opening 222 is formed at the front end of dome-shaped electrode 22 of counter electrode 2, that is, at the end opposite to discharge electrode 1 that faces counter electrode 2. In the present exemplary embodiment, opening 222 is formed in a circular shape when viewed in the front-rear direction (first direction) as shown in
Further, a plurality of (for example, two) protruding electrodes 23 protruding from opening edge 222a (inner peripheral edge) is integrally formed in opening 222. Specifically, each of the plurality of protruding electrodes 23 is formed so as to protrude in the lateral direction (second direction) from opening edge 222a of opening 222. That is, each of the plurality of protruding electrodes 23 is formed so as to protrude from opening edge 222a of opening 222 toward the center of opening 222.
The plurality of protruding electrodes 23 is arranged, for example, at equal intervals along the circumferential direction of opening 222. The plurality of protruding electrodes 23 of the present exemplary embodiment is a pair of protruding electrodes 23, and the pair of protruding electrodes 23 is provided at positions distant from each other by 180 degrees in the circumferential direction of opening 222. In other words, the pair of protruding electrodes 23 is provided at positions symmetrical about the center of opening 222 as the point of symmetry (center of symmetry). Opening 222 and the pair of protruding electrodes 23 are formed (molded) by, for example, a punching die. The specific shape of protruding electrode 23 will be described in the section of “(2.3) Shape of protruding electrode”.
Dome-shaped electrode 22 formed on electrode body 21 of counter electrode 2 has a pair of caulking holes 211 penetrating in the front-rear direction (Y-axis direction) on both the left and right sides. Counter electrode 2 of the present exemplary embodiment is subjected to heat caulking after a pair of caulking projections 51 formed on housing 5 shown in
As shown in
Further, the plurality of Peltier elements 411 is mechanically connected to discharge electrode 1 via insulating plate 413. That is, discharge electrode 1 is mechanically connected to insulating plate 413 via base end 12. On the other hand, the plurality of Peltier elements 411 is mechanically connected to insulating plate 413 on the heat-absorbing side (upper side). Thus, discharge electrode 1 and the plurality of Peltier elements 411 are electrically insulated by insulating plate 413 and the like.
Cooling device 41 in the present exemplary embodiment cools discharge electrode 1 mechanically connected to Peltier elements 411 on the heat-absorbing side by applying a current to the plurality of Peltier elements 411. At this time, cooling device 41 cools entire discharge electrode 1 through base end 12 of discharge electrode 1. Accordingly, the moisture in the air condenses and adheres to the surface of discharge electrode 1 as condensation water. That is, liquid supply unit 4 is configured to cool discharge electrode 1 and generate condensation water as liquid 40 on the surface of discharge electrode 1. According to this configuration, liquid supply unit 4 supplies liquid 40 (condensation water) to discharge electrode 1 using the moisture in the air. This eliminates the need to provide another device for supplying and replenishing the liquid to discharge device 10.
As shown in
Specifically, voltage application unit 3 includes diode bridge 31, isolation transformer 32, capacitor 33, resistors 34 and 35, a pair of input terminals 361 and 362, a pair of output terminals 371 and 372, and the like.
Diode bridge 31 is, for example, an element in which four diodes are connected in bridge. A pair of input ends of diode bridge 31 is electrically connected to the pair of input terminals 361 and 362. A pair of output ends of diode bridge 31 is electrically connected between both ends of primary winding 321 of isolation transformer 32. Diode bridge 31 rectifies (for example, provides full-wave rectification of) the AC power from AC power supply AC input via the pair of input terminals 361 and 362.
Isolation transformer 32 includes primary winding 321 and secondary winding 322. Primary winding 321 is electrically insulated from and magnetically coupled to secondary winding 322. One end of secondary winding 322 is electrically connected to, for example, output terminal 371 of the pair of output terminals 371 and 372, and the other end of secondary winding 322 is electrically connected to other output terminal 372 via resistor 35. Further, smoothing capacitor 33 and resistor 34 are electrically connected in parallel between both ends of secondary winding 322.
AC power supply AC is electrically connected between the pair of input terminals 361 and 362 of voltage application unit 3. Counter electrode 2 is electrically connected to, for example, output terminal 371 of the pair of output terminals 371 and 372, and discharge electrode 1 is electrically connected to other output terminal 372.
Voltage application unit 3 applies a high voltage to discharge electrode 1 and counter electrode 2. Here, the “high voltage” indicates a voltage high enough to cause the abovementioned partial breakdown discharge between discharge electrode 1 and counter electrode 2. Specifically, voltage application unit 3 applies a DC voltage of, for example, about −4 kV to discharge electrode 1 with counter electrode 2 grounded via terminal piece 24. In other words, in a state where a high voltage is applied from voltage application unit 3 to discharge electrode 1 and counter electrode 2, a potential difference with a side of counter electrode 2 being high and a side of discharge electrode 1 being low is generated between discharge electrode 1 and counter electrode 2.
Note that the value of the high voltage applied from voltage application unit 3 to discharge electrode 1 and counter electrode 2 is set, as appropriate, depending on, for example, the shapes of discharge electrode 1 and counter electrode 2, the distance between discharge electrode 1 and counter electrode 2, etc.
According to voltage application unit 3 described above, when the application voltage applied between output terminals 371 and 372 reaches a predetermined voltage (a voltage at which a discharge starts), a discharge occurs between discharge electrode 1 and counter electrode 2. Along with the discharge, a relatively large discharge current flows through voltage application unit 3. At this time, the discharge current flows through resistors 34 and 35 of voltage application unit 3. Thus, the application voltage applied between output terminals 371 and 372 becomes smaller than the predetermined voltage, so that the discharge current is interrupted. After that, the application voltage increases due to the interruption of the discharge current, and reaches the predetermined voltage again. When the application voltage reaches the predetermined voltage, a discharge is generated between discharge electrode 1 and counter electrode 2 again, and a discharge current flows. Then, after that, the abovementioned operation is repeated. Accordingly, a discharge occurs intermittently.
Discharge device 10 according to the present exemplary embodiment aims to increase the produced amount of acidic components. To this end, discharge device 10 is configured such that a partial breakdown discharge occurs between discharge electrode 1 and protruding electrode 23 of counter electrode 2.
Further, in order to reduce the generated amount of ozone, discharge device 10 needs to have a configuration for concentrating an electric field on the tip of protruding electrode 23. In this case, protruding electrode 23 preferably has a triangular shape as shown in
Further, it is preferable that, in order to concentrate the electric field on tip 230 of protruding electrode 23 formed in a triangular shape, the angle (vertex angle θ1) of tip 230 of protruding electrode 23 is an acute angle. Meanwhile, protruding electrode 23 is formed (molded) by a punching die as described above. During formation, if the angle of tip 230 of protruding electrode 23 is too small, there is a high possibility that the punching die will be damaged. In view of this, it is preferable that, in order to concentrate the electric field on tip 230 of protruding electrode 23 while preventing damage of the punching die, the angle of tip 230 of protruding electrode 23 is, for example, 60 degrees or more. That is, as shown in
Note that the shape of the triangle is preferably an isosceles triangle including an equilateral triangle. In this case, if the length of base 231 of the triangle is L1, and the length of perpendicular line 233 from vertex 232 facing base 231 to base 231 is L2, Equation (1) is established.
From Equation (1), when vertex angle θ1 of the triangle is 60 degrees or more, length L1 of base 231 is longer than length L2 of perpendicular line 233. That is, base 231 of the triangle is longer than perpendicular line 233 from vertex 232 facing base 231 to base 231. In this case, it is further preferable that length L2 of perpendicular line 233 of the triangle is less than or equal to a half of radius r1 of opening 222, as shown in
Note that, in the present exemplary embodiment, length L1 of base 231 of the triangle of protruding electrode 23 is, for example, 1 mm or less.
On the other hand, when tip 230 of protruding electrode 23 is sharp, the electric field is likely to concentrate on tip 230. Therefore, electrolytic corrosion is likely to occur at tip 230 of protruding electrode 23 due to the electric field. As a result, the discharge state in the partial breakdown discharge between discharge electrode 1 and protruding electrode 23 may change over time due to shape variation by electrolytic corrosion. Therefore, it is more preferable that tip 230 of protruding electrode 23 has a curved surface such that the discharge state does not change over time.
In view of this, as shown in
With this configuration, the electric field is concentrated on the curved surfaces (first curved surface 230a and second curved surface 230b) formed on tips 230 of protruding electrodes 23. Therefore, the occurrence of electrolytic corrosion can be suppressed as compared with the configuration where tips 230 of protruding electrodes 23 are sharp. As a result, the occurrence of a change over time in the discharge state due to the shape variation of tips 230 of protruding electrodes 23 is suppressed. Consequently, the discharge state of discharge device 10 can be stably maintained for a long period of time.
Hereinafter, the partial breakdown discharge generated when the application voltage is applied between discharge electrode 1 and counter electrode 2 will be described with reference to
Discharge device 10 according to the present exemplary embodiment first causes a local corona discharge in liquid 40 retained on discharge electrode 1. Since discharge electrode 1 of the present exemplary embodiment is on the negative electrode side, the corona discharge generated in liquid 40 retained on discharge electrode 1 is a negative corona discharge.
Then, discharge device 10 develops the corona discharge generated in liquid 40 retained on discharge electrode 1 to a higher energy discharge. Due to the discharge with higher energy, discharge path 200 in which the partial dielectric breakdown occurs is formed between discharge electrode 1 and counter electrode 2.
At this time, the partial breakdown discharge is accompanied by partial dielectric breakdown between discharge electrode 1 and counter electrode 2, but dielectric breakdown is not continuously generated. That is, the partial breakdown discharge is a discharge in which the dielectric breakdown occurs intermittently. Therefore, the flow of the discharge current generated between discharge electrode 1 and counter electrode 2 also occurs intermittently. That is, in a case where the power supply (voltage application unit 3) does not have a current capacity required to maintain discharge path 200, the voltage applied between discharge electrode 1 and counter electrode 2 reduces as soon as the corona discharge develops to the partial breakdown discharge. As a result, discharge path 200 formed between discharge electrode 1 and counter electrode 2 is interrupted, and the discharge is stopped. Note that the “current capacity” indicates a capacity of current that can be released in a unit time.
Then, the discharge current flows intermittently between discharge electrode 1 and counter electrode 2 due to the repetition of generation and stop of the discharge as described above. As described above, in the partial breakdown discharge, a state having high discharge energy and a state having low discharge energy are repeated, and in that point, the partial breakdown discharge is different from a glow discharge and an arc discharge in which dielectric breakdown occurs continuously (that is, a discharge current is continuously generated).
More specifically, voltage application unit 3 first applies an application voltage between discharge electrode 1 and counter electrodes 2 which face each other with a gap therebetween. Accordingly, a discharge is generated between liquid 40 retained on discharge electrode 1 and counter electrode 2. At this time, when the discharge occurs, discharge path 200 in which dielectric breakdown partially occurs is formed between discharge electrode 1 and counter electrode 2.
That is, discharge path 200 in which dielectric breakdown occurs not entirely but partially (locally) is formed between discharge electrode 1 and counter electrode 2. Thus, in the partial breakdown discharge, discharge path 200 formed between discharge electrode 1 and counter electrode 2 does not reach entire dielectric breakdown, but has partial dielectric breakdown.
Here, discharge path 200 includes first dielectric breakdown region 201 generated around discharge electrode 1 and second dielectric breakdown region 202 generated around counter electrode 2 as described above. First dielectric breakdown region 201 is a region where dielectric breakdown occurs around discharge electrode 1. Second dielectric breakdown region 202 is a region where dielectric breakdown occurs around counter electrode 2.
At this time, discharge electrode 1 retains liquid 40 as shown in
First dielectric breakdown region 201 and second dielectric breakdown region 202 are generated apart from each other in discharge path 200 so as not to come into contact with each other. Therefore, discharge path 200 includes a region (insulation region) where dielectric breakdown does not occur at least between first dielectric breakdown region 201 and second dielectric breakdown region 202. Accordingly, in the partial breakdown discharge, the space between liquid 40 retained on discharge electrode 1 and counter electrode 2 does not reach entire dielectric breakdown, but has only partial dielectric breakdown, and the discharge current flows through the space via discharge path 200. That is, when discharge path 200 in which partial dielectric breakdown occurs, in other words, discharge path 200 partially including a region where dielectric breakdown does not occur, is used, a discharge current flows between discharge electrode 1 and counter electrode 2 through discharge path 200, and a discharge occurs.
In this case, second dielectric breakdown region 202 is basically generated around the portion of counter electrode 2 where the distance (spatial distance) to discharge electrode 1 is the shortest. In discharge device 10 according to the present exemplary embodiment, angle θ2 between central axis P1 of discharge electrode 1 and the protrusion direction (X-axis direction) of protruding electrode 23 is 90 degrees as shown in
Here, counter electrode 2 of the present exemplary embodiment has a plurality of (for example, two) protruding electrodes 23 as described above. Protruding electrodes 23 are disposed such that distance D3 from each protruding electrode 23 to discharge electrode 1 is the same. Therefore, second dielectric breakdown region 202 is generated in the vicinity of the periphery of second curved surface 230b of tip 230 of any one of protruding electrodes 23 among the plurality of protruding electrodes 23. That is, protruding electrode 23 on which second dielectric breakdown region 202 is generated is not limited to specific protruding electrode 23, and is randomly determined among the plurality of protruding electrodes 23 due to various factors in the event of a discharge.
In other words, in the partial breakdown discharge, first dielectric breakdown region 201 is generated in the vicinity of the periphery of discharge electrode 1 so as to extend from discharge electrode 1 toward counter electrode 2 which is a counterpart as shown in
As described above, in the partial breakdown discharge, the region where dielectric breakdown partially occurs (first dielectric breakdown region 201 and second dielectric breakdown region 202) is generated to have a shape extending in a specific direction along discharge path 200.
Further, in the abovementioned partial breakdown discharge, a large amount of energy is generated as compared with the corona discharge. Due to the large amount of energy, oxygen and nitrogen in the air chemically react with each other, for example, to generate an acidic component such as nitrogen oxide. When attached to, for example, skin, the generated acidic component makes the skin mildly acidic. Therefore, the acidic component accelerates, in the skin, the production of moisturizing ingredients such as natural moisturizing molecules and intercellular lipids. In other words, the acidic component has an effect of boosting the ability of the skin to retain moisture. In addition, the acidic component tightens cuticle that covers the surface of the hair. That is, the acidic component also has an effect of preventing discharge of water, nutrients, and the like from inside of the hair.
In addition, when acidic components are generated by the partial breakdown discharge, ozone is also generated simultaneously. Meanwhile, discharge device 10 according to the present exemplary embodiment is configured such that an electric field is concentrated on tip 230 of protruding electrode 23. Accordingly, the generated amount of ozone can be suppressed to the same extent as that in a corona discharge.
Further, in the partial breakdown discharge, large amounts of radicals about 2 to 10 times as much as that in the corona discharge are generated. The generated radicals are the basis for providing useful effects in various situations, besides sterilization, deodorization, moisture retention, freshness retention, and inactivation of viruses. Therefore, the generated radicals can also be effectively utilized.
Hereinafter, a product produced by discharge device 10 according to the present exemplary embodiment will be described with reference to
First, the produced amount of acidic components by the discharge generated between discharge electrode 1 and counter electrode 2 will be described with reference to
In
That is, in
It can be seen from
That is, due to the configuration in which the partial breakdown discharge is generated between discharge electrode 1 and counter electrode 2, and protruding electrode 23 is provided on counter electrode 2, discharge device 10 according to the present exemplary embodiment can significantly increase the produced amount of acidic components.
Next, the generated amount of ozone generated by the discharge caused between discharge electrode 1 and counter electrode 2 will be described with reference to
Similar to
That is, in
It can be seen from
That is, it can be found that, in discharge device 10 in which protruding electrode 23 is provided on counter electrode 2, the generated amount of ozone decreases in both the corona discharge and the partial breakdown discharge.
Here, the reason why the generated amount of ozone decreases is presumed as follows. First, the reaction between ozone and nitrogen or nitrogen oxides proceeds due to the discharge between discharge electrode 1 and counter electrode 2 (protruding electrode 23). Accordingly, ozone disappears, and it is estimated that the generated amount of ozone will decrease.
Further, as shown in
It can be found from the above results that, considering both amounts, the configuration in which the partial breakdown discharge is caused, and protruding electrode 23 is provided on counter electrode 2 is the most preferable. That is, due to the configuration in which the partial breakdown discharge is generated between discharge electrode 1 and counter electrode 2, and protruding electrode 23 is provided on counter electrode 2, discharge device 10 can reduce the generated amount of ozone, while increasing the produced amount of acidic components.
Next, the produced amount of charged fine particle water by the partial breakdown discharge caused between discharge electrode 1 and counter electrode 2 will be described with reference to
In
It can be seen from
The exemplary embodiment is only one of various exemplary embodiments of the present disclosure. The exemplary embodiment described above can be variously modified according to the design and the like as long as the object of the present disclosure can be achieved. Modifications of the abovementioned exemplary embodiment will be described below. Further, the modifications described below can be applied in combination as appropriate.
In the abovementioned exemplary embodiment, angle θ2 between central axis P1 of discharge electrode 1 and the protrusion direction of protruding electrode 23 is 90 degrees as shown in
In the abovementioned exemplary embodiment, a plurality of protruding electrodes 23 is arranged so as to face each other in the lateral direction (X-axis direction) as shown in
Further, in the abovementioned exemplary embodiment and the second modification, a number of protruding electrodes 23 and 23A is two as an example, but the present disclosure is not limited thereto. For example, as in the third modification shown in
In
That is, in the third modification, four protruding electrodes 23B are positioned at 45 degrees, 135 degrees, 225 degrees, and 315 degrees when counter electrode 2B is viewed from front (Y-axis direction), as shown in
Further, in the fourth modification, four protruding electrodes 23C are positioned at 0 degrees, 90 degrees, 180 degrees, and 270 degrees when counter electrode 2C is viewed from front, as shown in
Further, in the abovementioned exemplary embodiment and the second to fourth modifications, protruding electrodes 23 and 23A to 23C are formed integrally with electrode bodies 21 of counter electrodes 2 and 2A to 2C, but the present disclosure is not limited thereto. For example, as shown in the fifth modification shown in
According to the second to fifth modifications, protruding electrodes 23A to 23D are provided on counter electrodes 2A to 2D, and a partial breakdown discharge is generated between discharge electrode 1 and protruding electrodes 23A to 23D. Thus, similar to discharge device 10 in the above exemplary embodiment, the generated amount of ozone can be reduced while increasing the produced amount of acidic components.
Hair care device 100 equipped with discharge device 10 using counter electrode 2 according to the above exemplary embodiment and hair care device 100A equipped with discharge device 10A using counter electrode 2A according to the second exemplary embodiment will be described below with reference to
Note that flow path 300 shown in
In
On the other hand, in
For the above reasons, it is preferable that the plurality of protruding electrodes 23 is arranged in flow path 300 of airflow generated by airflow generator 20 and at positions where the airflow flows at substantially the same velocity.
The mode of discharge adopted by discharge device 10 is not limited to the mode described in the exemplary embodiment described above. For example, discharge device 10 may employ a discharge in a mode in which a phenomenon where dielectric breakdown occurs due to development of a corona discharge is intermittently repeated, that is, discharge device 10 may employ an “entire breakdown discharge”. In this case, when dielectric breakdown occurs due to development of a corona discharge, a relatively large discharge current momentarily flows through discharge device 10. As a result, immediately after that, the application voltage drops, and the discharge current is interrupted. Thereafter, the application voltage rises again, and dielectric breakdown occurs. Such phenomenon is repeated.
Further, the number of protruding electrodes 23 is not limited to two or four, and may be, for example, one, three, or five or more. This can extend the life of electrodes.
Further, in the exemplary embodiment and modifications mentioned above, a plurality of protruding electrodes 23 is arranged at equal intervals in the circumferential direction of opening 222 as an example, but the configuration in which the plurality of protruding electrodes 23 is arranged at equal intervals is not necessary. For example, a plurality of protruding electrodes 23 may be arranged at arbitrary intervals in the circumferential direction of opening 222.
Further, discharge device 10 may not include liquid supply unit 4 that generates charged fine particle water. In this case, discharge device 10 generates air ions by the partial breakdown discharge generated between discharge electrode 1 and counter electrode 2. Accordingly, when mounted on, for example, a dryer, discharge device 10 can increase an effect of managing hair due to generation of negative ions in addition to acidic components.
In addition, in comparison between two values such as a threshold and a target value, the wording “greater than or equal to” includes both a case where the two values are equal to each other and a case where one of the two values exceeds the other. However, the present disclosure is not limited thereto, and the wording “greater than or equal to” herein may have the same meaning as the wording “greater than” which includes only a case where one of the two values exceeds the other. In other words, whether the wording “greater than or equal to” includes the case where the two values are equal to each other can be arbitrarily changed depending on setting of a threshold or the like. Therefore, there is no technical difference between the wording “greater than or equal to” and the wording “greater than”. Similarly, the wording “less than” may have the same meaning as the wording “less than or equal to”.
As described above, discharge device (10; 10A) according to one aspect of the present disclosure includes discharge electrode (1), counter electrode (2; 2A to 2D), and voltage application unit (3). Counter electrode (2; 2A to 2D) faces discharge electrode (1) in a first direction (for example, the front-rear direction). Voltage application unit (3) generates a discharge by applying an application voltage between discharge electrode (1) and counter electrode (2; 2A to 2D). Counter electrode (2; 2A to 2D) includes dome-shaped electrode (22) and protruding electrode (23; 23A to 23D). Dome-shaped electrode (22) has recessed inner surface (221) recessed to a side opposite to discharge electrode (1) in the first direction. Protruding electrode (23; 23A to 23D) protrudes in a second direction (for example, lateral direction) intersecting the first direction from opening edge (222a) of opening (222) of dome-shaped electrode (22), opening (222) being provided at an end opposite to discharge electrode (1). Discharge device (10) forms discharge path (200) that has at least partial dielectric breakdown between discharge electrode (1) and protruding electrode (23; 23A to 23D) when the discharge occurs. Discharge path (200) includes first dielectric breakdown region (201) and second dielectric breakdown region (202). First dielectric breakdown region (201) is generated around discharge electrode (1). Second dielectric breakdown region (202) is generated around protruding electrode (23; 23A to 23D).
According to this aspect, discharge path (200) including first dielectric breakdown region (201) and second dielectric breakdown region (202) is formed between discharge electrode (1) and protruding electrode (23; 23A to 23D). With this configuration, the produced amount of acidic components can be increased as compared with the case of the corona discharge. In addition, an electric field can be concentrated on a tip of protruding electrode (23; 23A to 23D). Accordingly, the generated amount of ozone can be suppressed to the same extent as that in the corona discharge.
Further, in discharge device (10; 10A) according to one aspect of the present disclosure, counter electrode (2; 2A to 2D) includes a plurality of protruding electrodes (23; 23A to 23D). The plurality of protruding electrodes (23; 23A to 23D) is arranged at equal intervals along the circumferential direction of opening (222).
According to this aspect, in a case where a Taylor cone is formed at tip (11) of discharge electrode (1), a variation in shape of the Taylor cone can be reduced. As a result, a dielectric breakdown state of protruding electrodes (23; 23A to 23D) can be stabilized.
Further, in discharge device (10; 10A) according to one aspect of the present disclosure, the plurality of protruding electrodes (23; 23A; 23D) is a pair of protruding electrodes (23; 23A; 23D).
According to this aspect, an electric field can be concentrated on protruding electrodes (23; 23A; 23D). As a result, the discharge between discharge electrode (1) and protruding electrode (23; 23A; 23D) can be stabilized.
Further, in discharge device (10; 10A) according to one aspect of the present disclosure, the shape of protruding electrode (23; 23A to 23D) as viewed in the first direction is a triangle.
According to this aspect, an electric field can be concentrated on tip (230) of protruding electrode (23; 23A to 23D). As a result, the discharge between discharge electrode (1) and protruding electrode (23; 23A to 23D) can be stabilized.
Further, in discharge device (10; 10A) according to one aspect of the present disclosure, vertex angle (01) of the triangle is 60 degrees or more.
According to this aspect, when the shape of protruding electrode (23; 23A to 23C) is punched by using, for example, a punching die, damage of the die can be reduced as compared with a configuration where vertex angle (01) is less than 60 degrees.
Further, in discharge device (10; 10A) according to one aspect of the present disclosure, base (231) of the triangle which is the shape of protruding electrode (23; 23A to 23D) is longer than perpendicular line (233). Perpendicular line (233) is a straight line from vertex (232) facing base (231) to base (231).
According to this aspect, when the shape of protruding electrode (23; 23A to 23C) is punched by using, for example, a punching die, damage of the die can be reduced as compared with a configuration where base (231) is shorter than perpendicular line (233).
Further, in discharge device (10; 10A) according to one aspect of the present disclosure, the shape of opening (222) as viewed in the first direction is circular. Length (L2) of perpendicular line (233) is less than or equal to a half of radius (r1) of opening (222).
According to this aspect, when the shape of protruding electrode (23; 23A to 23C) is punched by using, for example, a punching die, damage of the die can be reduced as compared with a configuration where length (L2) of perpendicular line (233) is longer than a half of radius (r1) of opening (222).
Further, in discharge device (10; 10A) according to one aspect of the present disclosure, the triangle which is the shape of protruding electrode (23; 23A to 23D) as viewed in the first direction is isosceles triangle.
According to this aspect, in a case where a Taylor cone is formed at tip (11) of discharge electrode (1), an occurrence of a variation in shape of the Taylor cone can be suppressed without fine adjustment. As a result, a stable discharge can be obtained between discharge electrode (1) and protruding electrode (23; 23A to 23D).
Further, in discharge device (10; 10A) according to one aspect of the present disclosure, first dielectric breakdown region (201) and second dielectric breakdown region (202) are formed apart from each other in discharge path (200).
According to this aspect, a discharge current can be reduced as compared with a case where dielectric breakdown is caused in entire discharge path (200). As a result, wear of protruding electrode (23; 23A to 23D) due to electrolytic corrosion can be reduced.
Further, in discharge device (10; 10A) according to one aspect of the present disclosure, protruding electrode (23; 23A to 23D) may be inclined in a direction away from discharge electrode (1) in the first direction.
According to this aspect, a direction of force acting on discharge electrode (1) and liquid (40) retained on discharge electrode (1) can be controlled by adjusting inclination angle (02) of protruding electrode (23; 23A to 23D). In addition, the location where the electric field is concentrated on protruding electrode (23; 23A to 23D) can be adjusted.
Further, in discharge device (10; 10A) according to one aspect of the present disclosure, a surface facing discharge electrode (1) at tip (230) of protruding electrode (23; 23A to 23D) includes a curved surface.
According to this aspect, tip (230) of protruding electrode (23; 23A to 23D) where an electric field is concentrated has a curved surface, whereby wear due to electrolytic corrosion can be reduced. As a result, a desired discharge state can be maintained for a long period of time.
Further, in discharge device (10; 10A) according to one aspect of the present disclosure, counter electrode (2; 2A) includes a plurality of protruding electrodes (23; 23A). The plurality of protruding electrodes (23; 23A) is arranged in flow path (300) of an airflow generated by airflow generator (20) and at positions where the airflow flows at the same velocity.
According to this aspect, imbalance of electrolytic corrosion caused between the plurality of protruding electrodes (23; 23A) can be reduced.
In addition, hair care device (100; 100A) according to one aspect of the present disclosure includes discharge device (10; 10A) according to the above aspect and airflow generator (20). Airflow generator (20) generates an airflow with respect to discharge device (10; 10A).
According to this aspect, hair care device (100; 100A) capable of increasing a produced amount of acidic components can be achieved using discharge device (10; 10A) described above.
It should be noted that all of the configurations described in each aspect of discharge device (10; 10A) are not necessary for discharge device (10; 10A) and can be eliminated as appropriate.
The discharge device according to the present disclosure can be applied to various applications such as refrigerators, washing machines, hair care devices such as hair dryers, air conditioners, electric fans, air purifiers, humidifiers, facial equipment, and automobiles.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2018-160761 | Aug 2018 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2019/003843 | 2/4/2019 | WO | 00 |
