JP6794597B2 - Electrostatic sprayer - Google Patents

Description

The present invention relates to an electrostatic spray device.

Patent Document 1 has an electrostatic nozzle device (electrostatic spray device) having a large number of nozzles, charging the liquid of each nozzle with the electrostatic force generated by applying a voltage, and spraying the liquid by the electrostatic force. ) Is disclosed.
Further, Patent Document 1 discloses that an electrostatic spray device is used as a means for generating a charged mist used in an air purifier by using water as a liquid.

Japanese Patent Publication No. 2008-516766

When a liquid such as a paint is applied to an object to be coated by using such an electrostatic spray technique, for example, a high application efficiency close to almost 100% can be obtained.
However, since the work of applying the liquid such as paint to the object to be coated is performed from various directions depending on the shape of the object to be coated, for example, the liquid may be sprayed in the horizontal direction.

In this case, for example, the nozzle located on the lower side is supplied with more liquid by the weight of the liquid than the nozzle located on the upper side, and the nozzle located on the lower side sprays the liquid to be sprayed. The amount is greater than the amount of liquid sprayed by the nozzle located on the upper side.
If there is such a variation in the amount of liquid sprayed, it may cause uneven coating or the like.

The present invention has been made in view of such circumstances, and is an electrostatic spraying device having a plurality of nozzles, and reduces variation in the amount of liquid sprayed from each nozzle regardless of the liquid spraying direction. It is an object of the present invention to provide an electrostatic spraying device capable of performing.

The present invention is grasped by the following configuration in order to achieve the above object.
(1) The electrostatic spraying device of the present invention is an electrostatic spraying device that separates a liquid from a nozzle of a liquid spraying portion in a charged state by an electrostatic force generated by applying a voltage and sprays the liquid onto an object to be coated. The liquid spraying portion is attached to the first head portion having the outflow portion for discharging the liquid and the first head portion so as to cover the outflow portion, and the second head is provided with a plurality of the nozzles. A portion and a resistance portion provided on a flow path through which the liquid flows from the outflow portion to the plurality of nozzles and having a flow path resistance are provided.

(2) In the configuration of (1) above, the liquid spraying portion is formed at the mating portion of the first head portion and the second head portion, and the second head portion is attached to the first head portion. When a plurality of grooves are provided to form a flow path corresponding to the plurality of nozzles that supply the liquid from the outflow portion side to the nozzle side, the resistance portion changes the shape of the groove portion to the flow path resistance. It is formed by forming a shape having.

(3) In the configuration of (2) above, the first head portion includes at least a first surface that is a part of the mating portion, and the second head portion is at least a part of the mating portion. A second surface corresponding to the first surface is provided, and the first surface is a surface of the first head portion that faces the second surface of the second head portion and is provided with the outflow portion. The second surface is the surface of the second head portion that faces the outflow portion of the first head portion and has a plurality of first openings corresponding to the plurality of nozzles that supply the liquid to the nozzles. , At least one of the first surface or the second surface so that the plurality of the groove portions form the flow path connecting the outflow portion and the first opening corresponding to the groove portion, respectively. It is formed on the surface of.

(4) In any one of the above (2) to (3), the grooves have substantially the same length.

(5) In the configuration of (1) above, the first head portion includes a first surface provided with the outflow portion, and the second head portion faces the outflow portion of the first head portion. A second surface having a plurality of first openings corresponding to the plurality of nozzles for supplying liquid to the nozzle is provided, and the first surface and the second surface are such that the second head portion is the first head. When attached to the portion, they are arranged apart so as to form a space that forms at least one part of the flow path through which the liquid flows from the outflow portion to the plurality of nozzles. The resistance portion is formed by providing a resistance member for generating the flow path resistance in the space.

(6) In the configuration of (1) above, the first head portion includes a first surface provided with the outflow portion, and the second head portion faces the outflow portion of the first head portion. A second surface having a plurality of first openings corresponding to the plurality of nozzles for supplying liquid to the nozzle is provided, and the first surface and the second surface have the second head portion as the first head. When attached to the portion, they are arranged apart so as to form a space that forms at least one part of the flow path through which the liquid flows from the outflow portion to the plurality of nozzles. The resistance portion is formed by providing a plurality of resistance members corresponding to each of the first opening, one end of which is led out into the space and the other end of which is inserted from the first opening to the nozzle side. ing.

(7) In the configuration of (5) or (6), the distance between the resistance member and the nozzle from the outflow portion is substantially the same.

(8) In the configuration of (1) above, the first head portion includes a first surface provided with the outflow portion, and the second head portion faces the outflow portion of the first head portion. A second surface having a plurality of first openings corresponding to the plurality of nozzles for supplying liquid to the nozzle is provided, and the first surface and the second surface are such that the second head portion is the first head. When attached to the portions, they are spaced apart so as to form a space that forms at least one portion of the flow path through which the liquid flows from the outflow portion to the plurality of nozzles. The liquid spraying portion is provided on at least the first surface or the second surface, and when the second head portion is attached to the first head portion, the liquid is discharged from the outflow portion side to the nozzle side. A plurality of groove portions corresponding to the plurality of nozzles forming a dominant flow path, and the first surface are provided between the first surface and the second surface so that a part of the groove falls into the groove. A resistance member sandwiched by the second surface is provided, and the resistance portion is formed by the groove portion and the resistance member.

(9) In any one of the above (5) to (8), the resistance member is a member containing a fiber or a porous body.

(10) In any one of the configurations (1) to (9), the second head portion is provided so that the liquid flowing out from the outflow portion of the first head portion is supplied to the nozzle. A plurality of second openings corresponding to the plurality of nozzles into which the nozzles are inserted are provided, and the plurality of the second openings are external surface portions of the second head portion located on the opposite side of the first head portion. The plurality of second openings are arranged so as to be located on concentric circles.

(11) In the configuration of (10) above, the plurality of nozzles are arranged so as to be inclined so that the tip portion of the nozzle is located on a concentric circle having a diameter larger than the concentric circle in which the second opening is arranged. There is.

(12) In any one of the above (1) to (11), the distance between the tip portions of the nozzles farthest from each other is H mm, and the resistance portion is any of the plurality of nozzles. It has the flow path resistance of 9.8 HPa or more when combined with the flow path resistance of one of the nozzles .

(13) In any one of the above (1) to (12), the liquid spraying portion is provided with a pump for supplying the liquid, and the resistance portion is relative to the supply pressure for supplying the liquid of the pump. It has 90% or less of the flow path resistance.

(14) In any one of the above configurations (1) to (13), the voltage applying means and the conductive material provided on the outer surface portion of the second head portion located on the opposite side of the first head portion. Alternatively, the connection electrode is provided with a material having a surface resistance of 10 ¹⁰ Ω or less, the first head portion and the second head portion are formed of an insulating material, and a plurality of the nozzles are made of a conductive material or 10 ¹⁰ Ω or less. The surface resistance material is formed of, and a plurality of the nozzles are connected by the connection electrode, and one of the plurality of the nozzles or the connection electrode is electrically connected to the voltage application means. Has been done.

According to the present invention, there is provided an electrostatic spraying device having a plurality of nozzles, which can reduce variations in the amount of liquid sprayed from each nozzle regardless of the liquid spraying direction. be able to.

It is a side view of the electrostatic spraying apparatus of 1st Embodiment which concerns on this invention. It is a front view which looked at the liquid spray part of 1st Embodiment which concerns on this invention from the side where the liquid is sprayed. FIG. 2 is a cross-sectional view taken along the line AA of FIG. It is a top view which looked at the 2nd surface of the 2nd head part of 1st Embodiment which concerns on this invention in front. It is an exploded perspective view of the liquid spray part of the 2nd Embodiment which concerns on this invention. It is sectional drawing of the liquid spray part of the 2nd Embodiment which concerns on this invention. It is sectional drawing of the liquid spray part of 3rd Embodiment which concerns on this invention. It is sectional drawing of the liquid spray part of 4th Embodiment which concerns on this invention.

Hereinafter, embodiments for carrying out the present invention (hereinafter, embodiments) will be described in detail with reference to the accompanying drawings.
The same elements are numbered the same throughout the description of the embodiment.
Unless otherwise specified, expressions such as "front (end)" and "front (direction)" represent the spraying direction side of the liquid in each member, etc., and "rear (end)" and "rear (direction)". The expression such as "" means the side opposite to the spraying direction of the liquid in each member or the like.

(First Embodiment)
FIG. 1 is a side view of the electrostatic spray device 10 according to the first embodiment of the present invention.
In addition, in FIG. 1, the place where the liquid is sprayed from the nozzle 31 is also schematically shown.

As shown in FIG. 1, the electrostatic spraying device 10 includes a liquid spraying unit 20 having a plurality of nozzles 31, a voltage applying means 60 for applying a voltage between the liquid spraying unit 20 and the object to be coated 50, and a liquid spraying unit. A pump 72 that supplies a liquid such as paint in the liquid storage tank 70 to the unit 20 via a liquid supply pipe 71, and a ground connected to a first electric wiring 61 connected to the object to be coated 50 from the voltage applying means 60. It has means 80 and.

In the present embodiment, the object to be coated 50 is grounded by the grounding means 80, but the grounding means 80 is not an indispensable requirement.
However, since the object to be coated 50 may be touched by an operator, it is preferable to provide a grounding means 80 to ground the object to be coated 50 from the viewpoint of safety.

(pump)
The pump 72 is a supply device that supplies the liquid in the liquid storage tank 70 to the liquid spray unit 20 via the liquid supply pipe 71 at a predetermined supply pressure.

Then, the liquid supplied by the pump 72 is supplied to each nozzle 31 through the flow path in the liquid spray unit 20.

(Voltage application means)
The voltage applying means 60 is a voltage power source for applying a voltage between the object to be coated 50 and the liquid spraying portion 20.
Then, when a voltage is applied between the object to be coated 50 and the liquid spraying portion 20 by the voltage applying means 60, an electrostatic force is generated between the object to be coated 50 and the liquid spraying portion 20.
The liquid supplied to each nozzle 31 is charged by this electrostatic force, and the liquid is separated from the nozzle 31 by the electrostatic force and sprayed.

Specifically, the liquid supplied to the tip side of the nozzle 31 is the tip of the nozzle 31 by balancing the electrostatic force that pulls the liquid forward with the adhesive force due to the surface tension and viscosity of the tip of the nozzle 31. A tailor cone 90 having a conical shape is formed.

The tailor cone 90 is formed in a conical shape by separating positive / negative charges in the liquid by the action of an electric field and deforming the meniscus at the tip of the nozzle 31 charged with excess charge.
Then, the liquid is further pulled from the tip of the tailor cone 90 by an electrostatic force, and then the liquid is sprayed by an electrostatic explosion.

The sprayed liquid, that is, the liquid that has separated from the nozzle 31 and becomes liquid particles, has a dramatically larger area in contact with air than the state before the separation, so that the vaporization of the solvent is promoted, and the solvent of the sprayed liquid. With vaporization, the distance between the charged electrons becomes shorter, electrostatic repulsion (electrostatic explosion) occurs, and the liquid particles have a smaller particle size.

When this split occurs, the surface area that comes into contact with the air increases compared to before the split, which promotes the vaporization of the solvent, causes an electrostatic explosion as described above, and further, a liquid having a small particle size. Split into particles.
The liquid is atomized by repeating such electrostatic explosion.

Since the liquid sprayed in this way is charged, it is attracted to the object to be coated 50 by the electrostatic force and is applied to the object to be coated 50 with high efficiency.

(Liquid spray part)
FIG. 2 is a front view of the liquid spraying portion 20 as viewed from the side where the liquid is sprayed, and FIG. 3 is a sectional view taken along line AA of FIG.
As shown in FIG. 3, the liquid spraying section 20 covers the first head section 40 having the outflow section 42 from which the liquid supplied to the supply section 41 by the pump 72 (see FIG. 1) flows out, and the outflow section 42. The second head portion 30 is attached to the first head portion 40 and is provided with a plurality of nozzles 31.

Further, the second head portion 30 communicates with the first opening 35, which is a supply port for the liquid to the nozzle 31, and the first opening 35, and the liquid flowing out from the outflow portion 42 of the first head portion 40 is a nozzle. A plurality of second openings 38 corresponding to the plurality of nozzles 31 into which the nozzles 31 are inserted are provided so as to be supplied to the 31.

The plurality of second openings 38 are provided on the outer surface portion 39 on the front side of the second head portion 30 located on the opposite side of the first head portion 40, and the arrangement state of the nozzles 31 in FIG. 2 can be seen. As can be seen, the plurality of second openings 38 are arranged so as to be located on concentric circles.

Further, in the present embodiment, the first head portion 40 and the second head portion 30 are formed of an insulating material, and the plurality of nozzles 31 are formed of a conductive material or a material having a surface resistance of 10 ¹⁰ Ω or less. There is.

Then, as shown in FIGS. 2 and 3, the liquid spraying portion 20 is provided on the outer surface portion 39 on the front side located on the opposite side of the first head portion 40 of the second head portion 30, and the nozzle 31 is inserted. It has a through hole to be formed, and is provided with a ring-shaped connecting electrode 23 formed of a conductive material for electrically connecting a plurality of nozzles 31 or a material having a surface resistance of 10 ¹⁰ Ω or less.

As shown in FIG. 1, the connection electrode 23 is connected to the other second electric wiring 62, which is an electric wiring different from the first electric wiring 61 connected to the object to be coated 50 from the voltage applying means 60. The connection electrode 23 is electrically connected to the voltage applying means 60.

The second head portion 30 is formed of a conductive material or a material having a surface resistance of 10 ¹⁰ Ω or less, and the second electric wiring 62 is connected to the second head portion 30 so that the connection electrode 23 is omitted. However, if the area of the portion to which the voltage is applied increases, sparks and the like are likely to occur. Therefore, it is preferable to provide the connection electrode 23 as in the present embodiment.

Further, since the plurality of nozzles 31 are in a state of being electrically connected, the second electric wiring 62 is connected to any one of the nozzles 31 instead of connecting the second electric wiring 62 to the connection electrode 23. As a result, one nozzle 31 may be electrically connected to the voltage applying means 60.

By the way, in order to satisfactorily separate the liquid from the nozzle 31 and spray it, the electrostatic force applied to the liquid is weak near the nozzle 31, and the liquid is pulled forward so as not to cause an electrostatic explosion, and the liquid tapers. It is preferable that the electrostatic force acts strongly on the tapered portion where the charged state is stable so as to extend to the front side so as to cause an electrostatic explosion.
That is, it is preferable that the electrostatic force applied to the liquid becomes stronger as the distance from the nozzle 31 increases.

Therefore, in the present embodiment, the plurality of nozzles 31 are arranged so as to be inclined so that the tip portion of the nozzle 31 is located on a concentric circle having a diameter larger than the concentric circle in which the second opening 38 is arranged.
That is, the nozzle 31 is arranged so as to be inclined outward so as to be farther from the central axis of the liquid spraying portion 20 toward the tip end side of the nozzle 31.

When the distance between the liquids extending from the nozzle 31 (hereinafter, the portion of the liquid from the tip of the nozzle 31 to the electrostatic explosion is called a liquid line) is short, the electrostatic force applied to each liquid line becomes weak. As described above, when the nozzle 31 is tilted, the liquid lines extending from the respective nozzles 31 are separated toward the front side, and a strong electrostatic force can act on each liquid line. It is possible to realize a preferable state in which the electrostatic force applied to the liquid becomes stronger as the distance from the liquid increases.

Next, a more detailed configuration of the first head portion 40 and the second head portion 30 will be described.
As shown in FIG. 3, the first head portion 40 is located at the center side of the flange portion 43 provided at the rear side position and the flange portion 43, and protrudes from the flange portion 43 toward the front side. The two head portions 30 have a first protruding portion 44 having a columnar outer shape, which is housed in the head portion 30.

Further, the first head portion 40 is provided at a position on the central side of the flange portion 43, and a supply portion 41 is formed which protrudes from the flange portion 43 toward the rear side and is connected to the liquid supply pipe 71 for supplying the liquid. It has a second protruding portion 45.
The first head portion 40 is formed with a through hole 46 penetrating the center of the first head portion 40 so as to communicate the supply portion 41 and the outflow portion 42.

On the other hand, the second head portion 30 is provided at a position on the rear side, and the flange of the first head portion 40 is formed with an opening having an inner diameter substantially equal to the outer diameter of the first protruding portion 44 of the first head portion 40 in the center. It has a flange portion 32 corresponding to the portion 43 and a recess that protrudes forward from the flange portion 32 and is open to the opening side of the flange portion 32 so as to have substantially the same outer shape as the outer shape of the first protruding portion 44 of the first head portion 40. It has a covering portion 33 and.

Then, in the first head portion 40 and the second head portion 30, as shown in FIG. 1, the flange portion 32 of the second head portion 30 and the flange portion 43 of the first head portion 40 are jointly tightened with screws 25. When the second head portion 30 is attached to the first head portion 40, the second head portion 30 is fitted at the mating portion.

Specifically, as shown in FIG. 3, the first end surface on the front side where the outer peripheral surface 44a of the first protruding portion 44 of the first head portion 40 and the outflow portion 42 of the first protruding portion 44 are provided. The surface 44b is on one side of the mating portion, and the inner peripheral surface 34a corresponding to the outer peripheral surface 44a of the first protruding portion 44 of the flange portion 32 of the second head portion 30 and the covering portion 33 and the outflow portion 42 of the first head portion 40. The second surface 34b (the surface corresponding to the first surface 44b) facing the surface is the other side of the mating portion, and the mating portion is formed.

FIG. 4 is a plan view of the second surface 34b of the second head portion 30 as viewed from the front.
As shown in FIG. 4, the second surface 34b faces the outflow portion 42 (see FIG. 3) of the first head portion 40 (see FIG. 3) and corresponds to a plurality of nozzles 31 that supply liquid to the nozzles 31. It is a surface of a second head portion 30 having a plurality of first openings 35.

Then, as shown in FIGS. 3 and 4, the liquid is placed on the second surface 34b at a central position corresponding to the outflow portion 42 provided on the first surface 44b (see FIG. 3) of the first head portion 40. A circular recess 36 is formed so as to form an ejection space for ejecting.

Further, as shown in FIG. 3, the liquid spraying portion 20 is a part of the mating portion of the first head portion 40 and the second head portion 30, and the first surface 44b and the second head portion of the first head portion 40. A plurality of groove portions 37 forming a flow path corresponding to a plurality of nozzles 31 for supplying a liquid from the outflow portion 42 side to the nozzle 31 side are provided in a portion where the second surface 34b of the 30 meets.

Specifically, as shown in FIG. 4, the plurality of groove portions 37 have the outflow portion 42 (more accurately, the recess 36 corresponding to the outflow portion 42) and the first opening 35 corresponding to the groove portion 37, respectively. It is formed on the second surface 34b of the second head portion 30 so as to form a flow path connecting the two.

A similar groove may be provided on the first surface 44b of the first head portion 40 facing the groove 37, and the grooves may be combined to form a flow path, or the groove may be formed. A groove may be provided in the portion of the first surface 44b of the first head portion 40 facing the 37, and the recess 36 and the groove 37 of the second surface 34b may be omitted.

Then, by making the shape of the groove portion 37 a shape having a predetermined flow path resistance, the liquid spraying portion 20 is provided with a resistance portion on the flow path through which the liquid flows from the outflow portion 42 to the plurality of nozzles 31. It has become.

For example, the groove portion 37 has a cross-sectional area such that when the second head portion 30 is attached to the first head portion 40, the flow path formed by the groove portion 37 becomes a resistance portion having an appropriate flow path resistance. It is formed in a shape.
However, if the length of the groove portion 37 can be increased, the flow path formed by the groove portion 37 may be formed in a shape having a length such that the resistance portion has an appropriate flow path resistance.
That is, the groove portion 37 may be formed so that the flow path formed by the groove portion 37 becomes a resistance portion having an appropriate flow path resistance according to the shape such as length, width, and depth.

More specifically, as shown in FIG. 2, when the distance L between the tips of the most distant nozzles 31 is H mm, the flow path resistance of the resistance portion formed by the groove 37 is the flow path resistance of the nozzle 31. The groove 37 is formed so as to be 9.8 HPA or more when combined with the flow path resistance.
The groove portions 37 are all set to have substantially the same length, and the flow path resistances of the resistance portions formed by the groove portions 37 are set to be substantially the same.
However, when designing the groove 37, it is easier to determine the shape of the groove 37 so that the flow path resistance of the resistance formed by the groove 37 is 9.8 HPa or more. Therefore, the first head When the second head portion 30 is attached to the portion 40, the groove portion 37 may be formed so that the flow path resistance of the flow path formed by the groove portion 37 is 9.8 HPa or more.

When such a resistance portion is provided, even when the central axis of the liquid spray portion 20 is horizontally arranged so as to spray the liquid in the horizontal direction, the nozzle 31 located on the upper side and the nozzle 31 located on the lower side are provided. Since there is a flow path resistance of 9.8 HPA or more due to the difference in position between the nozzle 31 located on the upper side and the nozzle 31 located on the lower side, the liquid is positioned on the lower side due to its own weight. It is possible to prevent the liquid from flowing to the nozzle 31 side, and to supply almost the same amount of liquid to any nozzle 31.

On the other hand, if the flow path resistance of the resistance portion is too large, the liquid cannot be satisfactorily supplied to each nozzle 31, so that the resistance portion is 90% or less of the supply pressure of the pump 72 that supplies the liquid. It is preferable to have resistance.

By the way, in a device that sprays a liquid from a nozzle 31 by electrostatic force, the inner diameter of the nozzle 31 is preferably, for example, about 0.2 mmφ or more and 0.5 mmφ or less in order to perform stable spraying. Since the cross-sectional area of the resistance portion that generates road resistance is often smaller than the cross-sectional area of the through hole of the nozzle 31, the resistance portion is likely to be clogged by foreign matter or the liquid itself.

If the resistance portion is formed as a through hole, the through hole becomes a fine through hole, and it is difficult to clear the clogging when the clogging is caused by a foreign substance or the liquid itself.

However, as described above, in the present embodiment, since the resistance portion is formed as the groove portion 37 which becomes the flow path when the second head portion 30 is attached to the first head portion 40, the resistance portion is formed with the first head portion 40. If the second head portion 30 is separated, the groove portion 37 can be easily cleaned.
Moreover, since the groove portion 37 is formed only on the second surface 34b of the second head portion 30 and the groove portion is not provided on the first surface 44b of the first head portion 40, the second surface 34b of the second head portion 30 is mainly formed. It suffices to clean the first surface 44b of the first head portion 40, so that the cleaning work can be made easier.
This is the same even if the groove portion is formed only on the first surface 44b of the first head portion 40 and the groove portion is not formed on the second surface 34b of the second head portion 30.
Therefore, even if clogging occurs in the resistance portion, the clogging can be easily cleared.

In the present embodiment, the outflow portion 42 through which the liquid flows out is provided on the first surface 44b, which is the front end surface of the first head portion 40. For example, the first protrusion of the first head portion 40. An outer peripheral groove connected in the circumferential direction is formed on the outer peripheral surface 44a of the portion 44, and an outflow portion 42 is provided in the outer peripheral groove, and the outer peripheral groove is connected to a plurality of first openings 35 of the second head portion 30. A resistance portion may be formed by providing a groove portion as a flow path.

(Second Embodiment)
Next, the second embodiment will be described with reference to FIGS. 5 and 6.
FIG. 5 is an exploded perspective view of the liquid spray unit 20 of the second embodiment, and FIG. 6 is a cross-sectional view similar to FIG. 3 of the liquid spray unit 20 of the second embodiment.

Also in the second embodiment, the overall configuration of the electrostatic spraying device 10 is basically the same as that of the first embodiment, only the configuration of the resistance portion included in the liquid spraying unit 20 is different.
Therefore, in the following, the configuration of the resistance portion will be mainly described, and the description may be omitted for the configuration similar to that of the first embodiment.

As shown in FIGS. 5 and 6, also in the second embodiment, the first head portion 40 includes a first surface 44b provided with an outflow portion 42.
Further, the second head portion 30 also has a second surface 34b that faces the outflow portion 42 of the first head portion 40 and has a plurality of first openings 35 corresponding to the plurality of nozzles 31 that supply liquid to the nozzles 31. ing.

On the other hand, in the second embodiment, as shown in FIG. 6, a plurality of first surface 44b and second surface 34b are formed from the outflow portion 42 when the second head portion 30 is attached to the first head portion 40. It is arranged so as to form a space that is at least one part of the flow path of the liquid leading to the nozzle 31, and a resistance member 27 that generates flow path resistance is provided in the space. A resistance portion is formed by.

For example, as the resistance member 27, a member made of fibers such as a non-woven fabric formed in the same outer shape as this space, or a member obtained by molding glass or ceramic into a porous body can be used.
It is preferable that the distances between the resistance members 27 from the outflow portion 42 to the respective nozzles 31 are substantially equal so that the flow path resistances are substantially equal.

Even if the resistance portion is configured in this way, it is possible to provide a flow path resistance corresponding to the water head pressure between the nozzles 31 as in the first embodiment, so that the liquid is sprayed in the horizontal direction. Even when the liquid spraying unit 20 is arranged horizontally, it is possible to prevent the liquid from flowing to the nozzle 31 side located on the lower side due to its own weight, and to supply almost the same amount of liquid to any nozzle 31. ..
In this case as well, the resistance portion itself may have a flow path resistance corresponding to the head pressure.

By the way, in the case of the second embodiment, the resistance member 27 can also function as a filter for removing foreign matter, and it is also possible to prevent clogging of the nozzle 31 caused by the foreign matter.

Further, if the resistance member 27 is manufactured inexpensively using a non-woven fabric or the like, the resistance member 27 can be made disposable and the labor for cleaning the resistance member 27 can be reduced.
Needless to say, the resistance member 27 may be washed and used repeatedly.

(Third Embodiment)
Next, the third embodiment will be described with reference to FIG. 7.
FIG. 7 is a cross-sectional view similar to that of FIG. 3 of the liquid spray unit 20 of the third embodiment.

Also in the third embodiment, the overall configuration of the electrostatic spraying device 10 is basically the same as that of the first embodiment, only the configuration of the resistance portion included in the liquid spraying unit 20 is different.
Therefore, in the following, the configuration of the resistance portion will be mainly described, and the description may be omitted for the configuration similar to that of the first embodiment.

As shown in FIG. 7, also in the third embodiment, the first head portion 40 includes a first surface 44b provided with an outflow portion 42.
Further, the second head portion 30 also has a second surface 34b that faces the outflow portion 42 of the first head portion 40 and has a plurality of first openings 35 corresponding to the plurality of nozzles 31 that supply liquid to the nozzles 31. ing.

On the other hand, in the third embodiment, as shown in FIG. 7, a plurality of first surface 44b and second surface 34b are provided from the outflow portion 42 when the second head portion 30 is attached to the first head portion 40. They are arranged apart so as to form a space that is at least one part of the flow path of the liquid leading to the nozzle 31.
The point of having such a space is the same as that of the second embodiment.

Then, as shown in FIG. 7, a plurality of resistance members 27 corresponding to each of the first opening 35 in which one end is led out into the space and the other end is inserted from the first opening 35 toward the nozzle 31 side. A resistance portion is formed by providing the above.

Therefore, in the second head portion 30, the portion where the nozzle 31 is inserted and fixed is thickened, and a through hole is formed so as to keep a distance between the first opening 35 and the nozzle 31. ..
The resistance member 27 is made of a non-woven fabric or the like having a rod-shaped body having a diameter matching the diameter of the first opening 35, or glass or ceramic having a diameter matched to the diameter of the first opening 35 formed into a porous body. A rod-shaped body having a diameter can be used.

Even if the resistance portion is configured in this way, as in the first embodiment and the second embodiment, a flow path resistance corresponding to the water head pressure can be provided between the nozzles 31 in the horizontal direction. Even when the liquid spraying unit 20 is arranged horizontally so as to spray the liquid, it is prevented that the liquid flows to the nozzle 31 side located on the lower side due to its own weight, and the amount of liquid is almost the same for all nozzles 31. Can be supplied.
Also in this third embodiment, the resistance portion itself may have a flow path resistance corresponding to the head pressure.

Further, the resistance member 27 can also function as a filter for removing foreign matter, and it is also possible to prevent clogging of the nozzle 31 caused by the foreign matter as in the second embodiment.

(Fourth Embodiment)
Next, the fourth embodiment will be described with reference to FIG.
FIG. 8 is a cross-sectional view similar to that of FIG. 3 of the liquid spraying unit 20 of the fourth embodiment.

Also in the fourth embodiment, the overall configuration of the electrostatic spraying device 10 is basically the same as that of the first embodiment, only the configuration of the resistance portion included in the liquid spraying unit 20 is different.
Therefore, in the following, the configuration of the resistance portion will be mainly described, and the description may be omitted for the configuration similar to that of the first embodiment.

As shown in FIG. 8, also in the fourth embodiment, the first head portion 40 includes a first surface 44b provided with an outflow portion 42.
Further, the second head portion 30 also has a second surface 34b that faces the outflow portion 42 of the first head portion 40 and has a plurality of first openings 35 corresponding to the plurality of nozzles 31 that supply liquid to the nozzles 31. ing.

On the other hand, in the first embodiment, the groove portion 37 provided in the liquid spraying portion 20 is provided on the second surface 34b of the second head portion 30, but in the fourth embodiment, the first surface of the first head portion 40. The point provided in 44b is different from the first embodiment.
However, the groove portion 37 may be provided on the second surface 34b of the second head portion 30 as in the first embodiment, and the second surface 34b and the first head portion 40 of the second head portion 30 may be provided. It may be provided on both sides of the first surface 44b of the above.

Further, in the fourth embodiment, as shown in FIG. 8, a plurality of the first surface 44b and the second surface 34b are formed from the outflow portion 42 when the second head portion 30 is attached to the first head portion 40. The liquid spraying portions 20 are arranged apart from each other so as to form a space that is at least one part of the flow path of the liquid leading to the nozzle 31, and the liquid spraying portions 20 are arranged on the first surface 44b and the second surface 34b. It is different from the first embodiment in that it is provided with a resistance member 27 provided between the two.
The resistance member 27 is the same as that of the second embodiment and the third embodiment, but a deformable material, for example, a member made of fibers such as a non-woven fabric is preferably used.

When the second head portion 30 is attached to the first head portion 40, the resistance member 27 is sandwiched between the first surface 44b and the second surface 34b so that a part thereof falls into the groove 37, and the groove portion A resistance portion is formed by the 37 and the resistance member 27.
Since the resistance member 27 that has fallen into the groove 37 is not strongly compressed, the liquid tends to flow predominantly.

That is, the plurality of groove portions 37 serve to form a path in which the liquid predominantly flows from the outflow portion 42 side to the nozzle 31 side, and the flow path resistance can be increased by the amount of the resistance member 27 provided. , It becomes easier to make the amount of liquid supplied to each nozzle 31 more uniform.

Even if the resistance portion is configured in this way, a flow path resistance corresponding to the water head pressure can be provided between the nozzles 31 as in the first embodiment, the second embodiment, and the third embodiment. Therefore, even when the liquid spraying portion 20 is horizontally arranged so as to spray the liquid in the horizontal direction, it is possible to prevent the liquid from flowing to the nozzle 31 side located on the lower side due to its own weight, and to any nozzle 31. Approximately equal amounts of liquid can be supplied.
Also in this fourth embodiment, the resistance portion itself may have a flow path resistance corresponding to the head pressure.

Further, the resistance member 27 can also function as a filter for removing foreign matter, and as in the second embodiment and the third embodiment, clogging of the nozzle 31 caused by the foreign matter can be prevented. It is possible.

Although the electrostatic spray device 10 of the present invention has been described above based on the specific embodiment, the present invention is not limited to the above specific embodiment.
For example, the resistance member 27 does not have to be composed of only a non-woven fabric or only a porous body made of glass or ceramic, and may be a member such as a composite material containing these.

In the case of such a composite material, since it can be made flexible even if it contains a porous body of glass or ceramic, the resistance member 27 that can be suitably applied to the fourth embodiment can be configured.

Further, based on the potential of the object to be coated 50, an electrode having a potential difference of about the middle of the potential difference between the object to be coated 50 and the liquid spray unit 20 is arranged in the vicinity of the liquid spray unit 20 to be arranged in the liquid spray unit. It may contribute to letting the liquid escape from the nozzle 31 of 20.

As described above, the present invention is not limited to the above-described embodiment, and those which have been appropriately modified or improved are also included in the technical scope of the present invention, which is a patent for those skilled in the art. It is clear from the description of the scope of claims.

10 Electrostatic spraying device 20 Liquid spraying part 23 Connection electrode 25 Screw 27 Resistance member 30 Second head part 31 Nozzle 32 Flange part 33 Covering part 34a Inner peripheral surface 34b Second surface 35 First opening 36 Recessed part 37 Groove part 38 Second Opening 39 Outer surface 40 First head 41 Supply 42 Outflow 43 Flange 44 First protrusion 44a Outer circumference 44b First surface 45 Second protrusion 46 Through hole 50 Subject 60 Voltage application means 61 First Electrical wiring 62 Second electrical wiring 70 Liquid storage tank 71 Liquid supply piping 72 Pump 80 Earthing means 90 Taylor cone L Distance

Claims (8)

An electrostatic spraying device that separates a liquid from the nozzle of the liquid spraying part in a charged state by the electrostatic force generated by applying a voltage and sprays the liquid onto an object to be coated.
The liquid spray unit
A first head portion having an outflow portion for flowing out the liquid, and
A second head portion attached to the first head portion so as to cover the outflow portion and provided with a plurality of the nozzles, and a second head portion.
It is provided on a flow path through which the liquid flows from the outflow portion to the plurality of nozzles, and includes a resistance portion having a flow path resistance .
The liquid spraying portion is formed at a joint portion between the first head portion and the second head portion, and when the second head portion is attached to the first head portion, the nozzle from the outflow portion side. A plurality of grooves forming a flow path corresponding to the plurality of nozzles for supplying the liquid are provided on the side.
An electrostatic spraying device characterized in that the resistance portion is formed by forming the shape of the groove portion into a shape having the flow path resistance . The first head portion includes at least a first surface that is a part of the mating portion.
The second head portion includes a second surface corresponding to the first surface that is at least a part of the mating portion.
The first surface is a surface of the first head portion that faces the second surface of the second head portion and is provided with the outflow portion.
The second surface is a surface of the second head portion that faces the outflow portion of the first head portion and has a plurality of first openings corresponding to the plurality of nozzles that supply the liquid to the nozzles. Yes,
Each of the plurality of grooves forms at least one of the first surface or the second surface so as to form the flow path connecting the outflow portion and the first opening corresponding to the groove portion. The electrostatic spray device according to claim 1 , wherein the electrostatic spray device is formed on a surface. The electrostatic spray device according to claim 1 or 2 , wherein all the grooves have substantially the same length. An electrostatic spraying device that separates a liquid from the nozzle of the liquid spraying part in a charged state by the electrostatic force generated by applying a voltage and sprays the liquid onto an object to be coated.
The liquid spray unit
A first head portion having an outflow portion for flowing out the liquid, and
A second head portion attached to the first head portion so as to cover the outflow portion and provided with a plurality of the nozzles, and a second head portion.
It is provided on a flow path through which the liquid flows from the outflow portion to the plurality of nozzles, and includes a resistance portion having a flow path resistance.
The first head portion includes a first surface provided with the outflow portion.
The second head portion includes a second surface facing the outflow portion of the first head portion and having a plurality of first openings corresponding to the plurality of nozzles that supply liquid to the nozzles.
The first surface and the second surface are at least one part of the flow path through which the liquid flows from the outflow portion to the plurality of nozzles when the second head portion is attached to the first head portion. They are arranged apart so as to form a space that becomes
The resistance portion is formed by providing a plurality of resistance members corresponding to each of the first opening, one end of which is led out into the space and the other end of which is inserted from the first opening to the nozzle side. An electrostatic spraying device characterized by being Electrostatic spraying device according to claim 4, the distance which the resistance member up to each of said nozzle from said outlet portion is Ru generates the flow path resistance is equal to or substantially equal. An electrostatic spraying device that separates a liquid from the nozzle of the liquid spraying part in a charged state by the electrostatic force generated by applying a voltage and sprays the liquid onto an object to be coated.
The liquid spray unit
A first head portion having an outflow portion for flowing out the liquid, and
A second head portion attached to the first head portion so as to cover the outflow portion and provided with a plurality of the nozzles, and a second head portion.
It is provided on a flow path through which the liquid flows from the outflow portion to the plurality of nozzles, and includes a resistance portion having a flow path resistance.
The first head portion includes a first surface provided with the outflow portion.
The second head portion includes a second surface facing the outflow portion of the first head portion and having a plurality of first openings corresponding to the plurality of nozzles that supply liquid to the nozzles.
The first surface and the second surface are at least one part of the flow path through which the liquid flows from the outflow portion to the plurality of nozzles when the second head portion is attached to the first head portion. They are arranged apart so as to form a space that becomes
The liquid spray unit
Provided on at least the first surface or the second surface, when the second head portion is attached to the first head portion, a path for the liquid to flow predominantly from the outflow portion side to the nozzle side is formed. With a plurality of grooves corresponding to the plurality of nozzles
A resistance member provided between the first surface and the second surface and sandwiched between the first surface and the second surface so that a part of the surface falls into the groove is provided.
An electrostatic spraying device characterized in that the resistance portion is formed of the groove portion and the resistance member. The electrostatic spray device according to any one of claims 4 to 6 , wherein the resistance member is a member containing a fiber or a porous body. The distance between the farthest tips of the nozzles is H mm.
The resistor unit from claim 1, characterized in that it comprises a plurality of said flow path resistance equal to or larger than 9.8 H Pa when combined with any one of the channel resistance of the nozzles of the nozzle The electrostatic spray device according to any one of claims 7 .

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