JP2018176080A - Electric dust collector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electric dust collector which secures proper generation of corona discharge over a long period of time by reducing an amount of particles adhering to a discharge electrode or the like.SOLUTION: An electric dust collector 1 collects by charging particles in the air by corona discharge, and includes: an outer cylindrical body 10 which is formed in a cylindrical shape with one end closed by an end surface part 10A and the other end opened; an inner cylindrical body 11 which is formed in a cylindrical shape with both ends opened, and is arranged by interposing a clearance with an inner circumferential surface and the end surface part 10A of the outer cylindrical body 10 in an inside of the outer cylindrical body 10; a plurality of discharge electrodes 27 which are supported by a support cylindrical body 26 arranged in an electrically insulating state from the outer cylindrical body 10 and the inner cylindrical body 11; and an air flow passage 15 which is formed so that air reversed and flowing in the clearance from a lower side of the outer cylindrical body 10 is distributed from a lower end to an upper end, and then a distribution direction of the air is reversed and the air is distributed from the upper end to the lower end inside the inner cylindrical body 11.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an electrostatic precipitator.

  There is known an electrostatic precipitator which charges and collects particles in air by corona discharge.

  For example, the smokeless roaster described in Patent Document 1 includes an electric dust collector in the middle of an exhaust passage for sucking in smoke, oil mist, and the like generated in a combustion unit. The electrostatic precipitating means is disposed inside a cylindrical electrode which is long in the vertical direction, and has a rod-like electrode which generates a corona discharge with the cylindrical electrode. When passing from the upper side to the lower side of the cylindrical electrode, smoke, oil mist and the like in the air are charged by corona discharge and collected on the inner side surface (partition) of the cylindrical electrode.

  Further, for example, the air cleaner described in Patent Document 2 includes a plus electrode made of a conductive synthetic resin plate and a brush-like minus electrode made of a stainless steel wire. The minus electrodes are arranged in a straight line on a plate and fixed, and the tip of the minus electrode is provided at a position facing the plus electrode. Dust and the like in the air are charged by corona discharge generated between the two electrodes when passing between the two electrodes, and collected by the plus electrode.

Japanese Patent Laid-Open No. 2000-084435 JP, 2016-107193, A

  However, in the smokeless roaster (electrostatic collection means) described in Patent Document 1, oil mist or the like generated in the combustion section linearly enters the inside of the cylindrical electrode from above and adheres to the rod-like electrode, thereby causing an appropriate corona. It may inhibit the discharge. Further, when oil mist, water or the like adheres to the rod-like electrode or the insulator that insulates between the two electrodes, creeping discharge may be easily generated. When creeping discharge occurs, the supply of high voltage may be stopped, or the electrostatic precipitating means may be broken. In addition, when a flame (fire powder) generated in the combustion section enters the inside of the cylindrical electrode, there is also a possibility that the oil or the like collected in the cylindrical electrode may be ignited.

  Moreover, the air cleaner described in Patent Document 2 generates corona discharge at a low applied voltage by adopting a brush-like negative electrode. However, since the negative electrode is provided only on one side of the plate, the number of negative electrodes may be small, and sufficient charging performance may not be satisfied. In addition, when the negative electrode was worn out and shortened due to long-term use, the distance between the positive electrode and the negative electrode (discharge gap) was changed, so that corona discharge could not be generated stably.

  In order to solve the above-described problems, the present invention provides an electrostatic precipitator that reduces the amount of particles adhering to a discharge electrode or the like to secure the generation of an appropriate corona discharge over a long period of time.

  In order to achieve the above-mentioned object, the first electrostatic precipitator of the present invention is an electrostatic precipitator which charges particles in the air by corona discharge and collects the particles, and one end is closed by an end face portion, And an outer cylinder formed as a cylindrical ground electrode open at the other end and a cylindrical ground electrode open at both ends, and the inner circumferential surface of the outer cylinder inside the outer cylinder The inner cylinder provided with a gap between the end surface portion and the outer cylinder and the inner cylinder are electrically insulated between the outer cylinder and the inner cylinder between the outer cylinder and the inner cylinder. Air flowing into the gap between the outer cylinder and the inner cylinder from the other end side of the outer cylinder, from the other end, the plurality of discharge electrodes supported by the support cylinder provided in the state; After flowing toward one end, the flow direction of air is reversed to move the inside of the inner cylinder from one end to the other And a, an air flow passage which is formed to pass.

  A second electrostatic precipitator according to the present invention is the first electrostatic precipitator described above, wherein the end face portion is provided on the upstream side in the flow direction of air, and the air flow path is a portion of the end face portion And, after flowing from one end to the other along the outer peripheral surface of the outer cylinder, the flow direction of air is reversed to flow into the gap between the outer cylinder and the inner cylinder. Is preferred.

  In the first and second electrostatic precipitators of the present invention, the air flow path is folded back inward at the outer other end of the outer cylinder and folded inward of the inner cylinder at the inner one end of the outer cylinder. It was formed in a substantially S-shape. According to this configuration, it is possible to separate heavy particles having a relatively large particle size among the particles in the air from the air by making a U-turn at the other end side of the outer cylinder with the air containing the particles. Therefore, air containing a large amount of particles is prevented from flowing into the gap (charged area) between the outer cylinder and the inner cylinder, and the amount (number) of particles attached to the discharge electrode can be reduced. Thereby, appropriate corona discharge can be generated over a long period of time. In addition, for example, since it is not necessary to dispose a demister or a prefilter or the like for separating and removing particles in the air in the air flow path, it is possible to reduce the manufacturing cost of the electrostatic precipitator. Furthermore, since the discharge electrode is provided inside the outer cylinder which becomes the ground electrode, for example, it is possible to suppress an operator from accidentally touching the discharge electrode at the time of maintenance or the like. As a result, the operator can safely perform maintenance work and the like, and can also prevent deformation and breakage of the discharge electrode.

  The third electrostatic precipitator according to the present invention is preferably the first or second electrostatic precipitator according to the present invention, wherein the outer cylindrical body is provided in a posture in which the end face portion is directed vertically upward. .

  According to the third electrostatic precipitator of the present invention, the particles in the air can be efficiently separated from the air by the U-turn of the air containing the particles at the lower portion outside the outer cylinder. In addition, inside the outer cylinder, the air flow path extends upward from the lower side, so that it is possible to effectively inhibit the entry of particles to the charged area. Further, even if droplets, fire powder, etc. are mixed in the air, the liquid droplets, fire powder, etc. are prevented from flowing directly into the inside of the electrostatic precipitator by the end face portion. Furthermore, as the air makes a U-turn at the outer lower part of the outer cylinder, among the particles in the air such as droplets and fire powder, heavy particles having a relatively large particle size fall downward, so droplets and fire powder etc. It is possible to suppress the flow into the inside of the electrostatic precipitator. Thereby, the electrostatic precipitator can be operated safely.

  A fourth electrostatic precipitator according to the present invention is the electrostatic precipitator according to any one of the first to third above, wherein the air flow path is the other end of the outer cylinder and the other end of the inner cylinder. And an annular second opening formed by the gap between the end face and the one end of the inner cylinder; and the inner cylinder And a third opening formed by the other open end, wherein the opening area of each of the first opening, the second opening and the third opening is the first opening, It is preferable that the flow velocity of the air passing through the second opening and the third opening is set to be constant.

  According to the fourth electrostatic precipitator of the present invention, since the flow velocity of the air passing through the first to third openings can be made substantially constant, it is possible to generate a stable air flow throughout the air flow path. it can. Thus, particles in the air flowing through the air flow path can be appropriately charged and collected.

  The fifth electrostatic precipitator according to the present invention is any one of the above-described first to fourth electrostatic precipitators, wherein the one end of the inner cylindrical body is inclined outward in the air flow direction from one end to the outside. It is preferable to further include an air flow guide formed.

  In the fifth electrostatic precipitator of the present invention, air containing particles collides with the air flow guide after passing through the charged area. According to this configuration, since the air flows along the air flow guide, the flow direction of the air can be directed to the outer cylinder side. Specifically, air can be guided to a boundary portion (corner portion) between the inner peripheral surface of the outer cylinder and the inner surface of the end surface portion. Thereby, the area (collection area) for adsorbing and collecting charged particles can be expanded, and the collection amount of particles can be increased. In addition, since the air flow guide is provided to partially block the flow of air, the flow velocity of air can be reduced in the charging area. Thereby, particles in the air can be appropriately charged, and adsorption and collection of particles can be properly performed.

  A sixth electrostatic precipitator according to the present invention is the electrostatic precipitator according to any one of the first to fifth above, wherein the support cylindrical body is formed in a cylindrical shape with both ends open, and the outer cylindrical body The inner cylinder and the support cylinder are respectively disposed on the same axial center, and the discharge electrode is provided at a position that bisects a gap between the outer cylinder and the inner cylinder. Is preferred.

  According to the sixth electrostatic precipitator of the present invention, the outer cylinder, the inner cylinder, and the support cylinder are disposed on the same axial center, and each discharge electrode is formed of the outer cylinder and the inner cylinder. Disposing the discharge electrode substantially at the center of the gap makes it possible to equalize the discharge gap between each discharge electrode and the two ground electrodes (the outer cylinder and the inner cylinder). As a result, it is possible to prevent extreme deterioration of only a part of the plurality of discharge electrodes, and to generate stable corona discharge over the entire area in the circumferential direction.

  A seventh electrostatic precipitator according to the present invention is the electrostatic precipitator according to any one of the first to sixth above, wherein the discharge electrodes are formed by bundling a plurality of fibrous line electrodes, and the support It is preferable to be provided so as to extend from the cylindrical body toward the upstream side and the downstream side of the air flow direction.

  According to the seventh electrostatic precipitator of the present invention, since a fibrous line electrode is used as the discharge electrode, corona discharge can be generated at a lower applied voltage than when a thick electrode is used. it can. As a result, the generation of sparks can be suppressed, and the generation of ozone accompanying the ionization of air can also be suppressed. Further, since the discharge electrodes are provided on both sides of the support cylinder in the flow direction, the number of discharge electrodes can be increased as compared to the case where the discharge electrodes are provided on one side of the support cylinder in the flow direction. As a result, the location of occurrence of corona discharge is increased, whereby particles in the air can be efficiently charged. Furthermore, since each discharge electrode extends substantially in parallel with the outer cylinder (circumferential surface) and the inner cylinder, the discharge gap can be kept substantially constant even when each discharge electrode is worn and shortened. it can. Thereby, stable corona discharge can be generated over a long period of time.

  An eighth electrostatic precipitator according to the present invention is the electrostatic precipitator according to any one of the first to seventh above, wherein the other end of the inner cylindrical body extends toward the downstream side in the air flow direction. Preferably, the apparatus further comprises a connection guide formed and connecting the exhaust pipe.

  According to the eighth electrostatic precipitator of the present invention, the inner cylinder and the exhaust pipe can be easily attached and detached via the connection guide. Thereby, the workability concerning cleaning and maintenance of the electrostatic precipitator and the exhaust pipe can be improved.

  A ninth electrostatic precipitator according to the present invention is the electrostatic precipitator according to any one of the first to eighth above, provided in a state of being bridged between the outer cylinder and the support cylinder. Preferably, the insulator further comprises a insulator electrically insulating the outer cylinder and the support cylinder.

  According to the ninth electrostatic precipitator of the present invention, by causing the support cylindrical body to be supported by the outer cylindrical body through the insulator, each discharge electrode is substantially parallel to the outer cylindrical body and the inner cylindrical body. It can be made to face each other. Thereby, stable corona discharge can be generated.

  According to a tenth electrostatic precipitator of the present invention, in the ninth electrostatic precipitator described above, preferably, the insulator includes a ridge portion formed so as to extend in parallel with the flow direction of air.

  According to the tenth electrostatic precipitator of the present invention, by providing the ridge portion on the insulator, it is possible to secure the creeping distance of the insulator necessary to suppress the creeping discharge. Thereby, the supply stop of the high voltage by the generation | occurrence | production of creeping discharge, the failure of the electrostatic precipitator, etc. can be suppressed.

  According to the present invention, the amount of particles adhering to the discharge electrode and the like can be reduced. Thereby, generation | occurrence | production of the appropriate corona discharge can be ensured over a long period of time.

It is a perspective view which shows the electrostatic precipitator which concerns on one Embodiment of this invention. It is a perspective view which shows the inside of the electrostatic precipitator which concerns on one Embodiment of this invention. It is a sectional view showing the electric precipitator concerning one embodiment of the present invention. It is sectional drawing which expands and shows a part of the electrostatic precipitator which concerns on one Embodiment of this invention. It is a bottom view showing the electrostatic precipitator concerning one embodiment of the present invention. It is sectional drawing which shows typically a part of discharge part of the electrostatic precipitator which concerns on one Embodiment of this invention. It is sectional drawing which shows the electric dust collector which concerns on the 1st modification of one Embodiment of this invention. It is sectional drawing which shows the electrostatic precipitator which concerns on the 2nd modification of one Embodiment of this invention. It is a perspective view which shows typically a part of discharge part of the electrostatic precipitator which concerns on the other modification of one Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the attached drawings. Note that "U" shown in the drawing indicates "upper" and "D" indicates "lower".

  The electrostatic precipitator 1 according to the present embodiment will be described with reference to FIGS. 1 to 6. FIG. 1 is a perspective view showing the electrostatic precipitator 1. FIG. 2 is a perspective view showing the inside of the electrostatic precipitator 1. FIG. 3 is a cross-sectional view showing the electrostatic precipitator 1. FIG. 4 is a cross-sectional view showing a part of the electrostatic precipitator 1 in an enlarged manner. FIG. 5 is a bottom view showing the electrostatic precipitator 1. FIG. 6 is a cross-sectional view schematically showing a part of the discharge portion 12 of the electrostatic precipitator 1.

  The electrostatic precipitator 1 is a device that charges and collects particles in air by corona discharge. Although not shown, for example, the electrostatic precipitator 1 is incorporated into a smokeless rooster that sucks in and discharges particles such as moisture (smoke), oil mist, oil mist and the like generated from foodstuffs and the like burned with a cooking device. It is done. The cooker is fixed to the inside of a bathtub-like housing frame 60 (see FIG. 3) embedded in the table. An upstream end of an exhaust pipe 61 communicating with the outside (outdoor) is provided on the bottom of the housing frame 60 so as to protrude. The exhaust pipe 61 is a metal pipe having a substantially circular cross section. The electrostatic precipitator 1 is provided in the accommodation frame 60 adjacent to the side of the cooker and connected to the upstream end of the exhaust pipe 61. On the downstream side of the exhaust pipe 61, a suction fan (not shown) is provided which exerts a suction force in the electric dust collector 1 and the housing frame 60 through the exhaust pipe 61.

[Electric dust collector]
As shown in FIGS. 1 and 2, the electrostatic precipitator 1 includes an outer cylindrical body 10, an inner cylindrical body 11, a discharge portion 12, a power feeding insulator 13, three supporting insulators 14, and an air flow. And a road 15. The outer cylindrical body 10 and the inner cylindrical body 11 are ground electrodes connected to a reference potential point (for example, the ground or the like). The discharge portion 12 includes a discharge electrode 27 that generates a corona discharge between the outer cylindrical body 10 and the inner cylindrical body 11. The feed insulator 13 and each support insulator 14 electrically insulate between the outer cylinder 10 and the discharge portion 12. The air flow passage 15 is a passage through which air containing particles flows. In the following description, the “flow direction” refers to the direction in which air flows. Also, “upstream” and “downstream” and similar terms refer to “upstream” and “downstream” and similar concepts in the flow direction of air.

<External cylinder>
As shown in FIGS. 1 and 2, the outer cylinder 10 is formed in a substantially cylindrical shape in which the upper end (one end) is closed by the end face portion 10A and the lower end (the other end) is opened. The outer cylinder 10 is made of, for example, stainless steel which is excellent in non-combustibility, conductivity and corrosion resistance. As shown in FIG. 3 and FIG. 4, one feed hole 20 and three support holes 21 are opened on the slightly lower side in the vertical direction of the peripheral wall 10 B of the outer cylinder 10. A total of four holes 20 and 21 are formed at substantially equal intervals (approximately 90 degrees intervals) in the circumferential direction of the outer cylindrical body 10. The diameter of the feed holes 20 is set larger than the diameter of each support hole 21 (see FIG. 3). Although details will be described later, the power supply insulator 13 and the three support insulators 14 are disposed corresponding to the four holes 20 and 21 (see FIG. 5).

  As shown in FIG. 5, four mounting plates 22 are fixed to the lower surface of the end face portion 10A. The four mounting plates 22 are provided at positions rotated approximately 45 degrees in the circumferential direction with respect to the four insulators 13 and 14 (four holes 20 and 21) when viewed from the bottom surface. As shown in FIG. 4, each mounting plate 22 is provided in a state of hanging down from the lower surface of the end face portion 10A. The lower end portion of each mounting plate 22 forms a bent piece 22A which is substantially horizontally bent. A round hole (not shown) is formed in each bent piece 22A, and a fixing nut N1 is fixed to the upper surface of each bent piece 22A coaxially with the round hole. The fixing nut N1 is also formed of stainless steel.

<Inner cylinder>
As shown in FIGS. 2 to 4, the inner cylindrical body 11 is formed in a substantially cylindrical shape which is shorter in the vertical direction than the outer cylindrical body 10 and whose both ends in the vertical direction are open. The diameter (outer diameter) of the inner cylinder 11 is set smaller than that of the outer cylinder 10. Similar to the outer cylinder 10, the inner cylinder 11 is formed of stainless steel.

  Four mounting stays 23 are fixed to the upper inner surface of the inner cylindrical body 11. The four mounting stays 23 are provided so as to extend radially inward from positions at substantially equal intervals (approximately 90 degrees) in the circumferential direction of the inner cylindrical body 11 (see FIG. 5). Each mounting stay 23 is formed with a circular hole (not shown).

(Airflow guide)
As shown in FIGS. 3 and 4, a substantially annular air flow guide 24 is attached to the upper end portion of the inner cylindrical body 11. The air flow guide 24 is formed to be inclined upward (downstream side in the flow direction) radially outward from the upper end (one end) of the inner cylindrical body 11. That is, the air flow guide 24 is formed so as to gradually spread upward (to enlarge the outer diameter). The angle α between the air flow guide 24 and the horizontal surface is set to, for example, approximately 30 degrees (see FIG. 4). The angle α of the air flow guide 24 can be set in the range of 30 to 45 degrees.

  At the lower end of the air flow guide 24, four mounting pieces 24A are integrally formed. The four attachment pieces 24A are provided to extend downward from positions at substantially equal intervals (approximately 90 degrees) in the circumferential direction of the air flow guide 24 (see FIG. 5). The air flow guide 24 is attached to the inner cylinder 11 by means such as adhesion with an adhesive or welding after the four attachment pieces 24A are inserted inside the inner cylinder 11. The air flow guide 24 may be press-fitted into the inner cylinder 11.

(Connection guide)
As shown in FIGS. 1 to 3, a substantially annular connection guide 25 is attached to the lower end portion of the inner cylindrical body 11. The connection guide 25 is formed so as to gradually spread (increase the outer diameter) downward (downstream in the flow direction) from the lower end (the other end) of the inner cylindrical body 11. The connection guide 25 is provided to connect the exhaust pipe 61. In addition, although the connection guide 25 is attached to the inner cylinder 11 by means, such as adhesion | attachment by an adhesive agent, and welding, you may be pressingly injected inside the inner cylinder 11 similarly to the airflow guide 24. FIG.

<Discharger>
As shown in FIGS. 2 to 4, the discharge unit 12 includes a support cylinder 26 and a plurality of discharge electrodes 27. The plurality of discharge electrodes 27 are supported by the support cylinder 26.

(Support cylinder)
The support cylindrical body 26 is shorter in the vertical direction than the inner cylindrical body 11, and is formed in a substantially cylindrical shape (substantially annular shape) in which both ends in the vertical direction are open. The diameter (outer diameter) of the support cylinder 26 is set smaller than the outer cylinder 10 and larger than the inner cylinder 11. The support cylinder 26 is formed of stainless steel in the same manner as the outer cylinder 10 and the like. As shown in FIG. 6, the support cylinder 26 includes an inner support cylinder 26B in close contact with the inside of the outer support cylinder 26A, and is formed in a double annular shape. As shown in FIGS. 3 and 4, in the outer support cylindrical body 26A and the inner support cylindrical body 26B, four support holes 28 which are long in the circumferential direction are opened. The four support holes 28 are formed at substantially equal intervals (approximately 90 degrees intervals) in the circumferential direction of the support cylinders 26A and 26B.

(Electrode for discharge)
As shown in FIG. 6, the base end of each discharge electrode 27 is sandwiched between the outer support cylindrical body 26A and the inner support cylindrical body 26B, and is crimped to both the support cylindrical bodies 26A and 26B. As shown in FIGS. 2 to 4, the plurality of discharge electrodes 27 extend from the support cylinder 26 toward the upper and lower sides (upstream and downstream in the flow direction). The plurality of discharge electrodes 27 are all formed to have substantially the same overall length, and the tips of the plurality of discharge electrodes 27 are substantially aligned. The protruding length of each discharge electrode 27 (the length from the upper end (lower end) of the support cylinder 26 to the tip of each discharge electrode 27) is set to about 5 mm. The plurality of discharge electrodes 27 are provided in a state of being arranged at substantially equal intervals (for example, about 5 mm) along the circumferential direction of the support cylinder 26. The plurality of discharge electrodes 27 are arranged in the same phase in the upper portion and the lower portion of the support cylinder 26. That is, the pair of discharge electrodes 27 opposed to each other with the support cylinder 26 interposed therebetween is provided on a straight line extending in the vertical direction.

  As shown in FIG. 6, each discharge electrode 27 is formed in a brush shape by bundling a plurality of fibrous line electrodes 27A. The wire electrode 27A is a stainless steel fiber having a diameter of 12 μm. In the present embodiment, for example, one discharge electrode 27 is formed by bundling about 100 of the line electrodes 27A.

<Power feed ladder>
As shown in FIG. 2 to FIG. 5, the feed ladder 13 includes a forceps main body 30 and a feed connection portion 31. The insulator main body 30 is formed separately from the feed connection portion 31. The insulator main body 30 and the feeding connection portion 31 are formed of, for example, porcelain or pottery having excellent electrical insulation, or a resin having excellent electrical insulation.

  The forceps main body 30 includes a body 30A and a buttock 30B. The body 30A is formed in a substantially cylindrical shape whose outer diameter is gradually reduced from the center in the longitudinal direction toward both ends. A through hole 30C is formed at the axial center of the body 30A (see FIG. 4). The collar portion 30B is formed in a substantially annular shape, spreading in the radial direction from the center in the longitudinal direction of the trunk portion 30A. The collar 30B is integrally formed with the body 30A.

  The feed connection portion 31 is formed in a substantially bottomed cylindrical shape having a diameter larger than that of the trunk portion 30A. The power supply connection portion 31 is formed with a recess 31A having an open end. As shown in FIG. 4, on the other end surface of the feed connection portion 31, a fitting convex portion 31 </ b> B having a diameter smaller than the maximum outer diameter of the feed connection portion 31 is formed to protrude. The fitting convex portion 31 </ b> B is formed to be able to be fitted to the power feeding hole 20 of the outer cylindrical body 10. In the bottom wall of the recess 31A, a through hole 31C is opened at the same axial center as the recess 31A.

<Support forceps>
As shown in FIG. 2, FIG. 3 and FIG. 5, the three support insulators 14 are respectively made of porcelain, pottery or resin having an excellent electrical insulation property, and radially from the longitudinal center of the body 14A. It includes the expanded buttocks 14B. A through hole 14C is formed at the axial center of each support insulator 14 (body part 14A). In addition, since each support forceps 14 is substantially the same as the forceps main body 30 of the power supply forceps 13, detailed description will be omitted.

[Assembly of electrostatic precipitator]
Here, the assembly procedure of the electrostatic precipitator 1 will be described. The air flow guide 24 and the connection guide 25 are attached to the inner cylindrical body 11.

  First, as shown in FIGS. 1 to 4, the operator inserts the inner cylinder 11 into the inside from the lower surface opening of the outer cylinder 10, and the four attachment stays 23 are bent pieces 22A of the four attachment plates 22. Abut the lower surface of the Then, the operator engages the mounting screw S1 passed from below to the circular hole of the mounting stay 23 etc. with the fixing nut N1 of the bending piece 22A. The mounting screw S1 is also formed of stainless steel.

  As described above, the inner cylindrical body 11 is provided in the inside of the outer cylindrical body 10 with the gap G interposed between the inner circumferential surface of the outer cylindrical body 10 and the end face portion 10A (see FIG. 1). In this state, the lower end surface of the outer cylindrical body 10 and the lower end surface of the inner cylindrical body 11 are located on substantially the same plane (see FIG. 3).

  Next, as shown in FIG. 1 to FIG. 4, the worker inserts the support cylinder 26 (discharge part 12) supporting the plurality of discharge electrodes 27 between the outer cylinder 10 and the inner cylinder 11. The four support holes 28 of the support cylinder 26 are aligned with the four holes 20 and 21 of the outer cylinder 10.

  Subsequently, as shown in FIG. 3 and FIG. 5, the operator inserts each support forceps 14 between the outer cylinder 10 and the support cylinder 26 to support the through holes 14C of each support forceps 14. Align with the holes 21. Then, the worker inserts each support screw S2 into the support hole 21 from the outside of the outer cylindrical body 10. Then, each support screw S 2 passes through the support hole 21, the through hole 14 C and the support hole 28, and the tip of each support screw S 2 protrudes inside the support cylindrical body 26. The operator engages the support nut N2 with the tip of each support screw S2 inside the support cylindrical body 26. The supporting screws S2 and the supporting nuts N2 are formed of a synthetic resin having heat resistance and electrical insulation.

  Further, as shown in FIG. 3 to FIG. 5, the operator inserts the forceps main body 30 between the outer cylindrical body 10 and the support cylindrical body 26, and positions the through hole 30 C of the forceps main body 30 at the feeding hole 20. Match. Further, the worker fits the fitting convex portion 31B of the feeding connection portion 31 into the feeding hole 20 from the outside of the outer cylindrical body 10. Then, the operator inserts the feeding coil spring 32 into the recess 31A of the feeding connection portion 31, and inserts the feeding screw S3 into the feeding coil spring 32 and the through hole 31C of the recess 31A. Then, the feed screw S3 passes through the through hole 31C, the through hole 30C, and the support hole 28, and the tip of the feed screw S3 protrudes to the inside of the support cylindrical body 26. The operator engages the feed nut N3 with the tip of the feed screw S3 inside the support cylinder 26. The feed screw S3 and the feed nut N3 are made of stainless steel.

  Thus, the assembly of the electrostatic precipitator 1 is completed. In this state, the feeding forceps 13 (the forceps main body 30) and the supporting forceps 14 are provided in a state of being bridged between the outer cylindrical body 10 and the supporting cylindrical body 26 (see FIG. 5). The support cylinder 26 (each discharge electrode 27) is provided in a state of being electrically insulated from the outer cylinder 10 and the inner cylinder 11 between the outer cylinder 10 and the inner cylinder 11. Moreover, the support cylinder 26 (discharge part 12) is arrange | positioned in the vertical direction approximate center part of the inner cylinder 11 (refer FIG. 3). Further, in this state, the outer cylindrical body 10, the inner cylindrical body 11, and the support cylindrical body 26 are disposed on the same axial center (concentric circle) (see FIG. 5). The support cylinder 26 and the discharge electrodes 27 are disposed substantially in parallel with the outer cylinder 10 (peripheral wall 10B) and the inner cylinder 11 (see FIG. 3).

  Further, as shown in FIG. 4, in a state where the electrostatic precipitator 1 is assembled, each discharge electrode 27 is at a position at which the gap G between the outer cylinder 10 and the inner cylinder 11 is bisected. It is provided. That is, the shortest distance (discharge gap A) connecting the discharge electrodes 27 and the outer cylinder 10 (peripheral wall 10B), and the shortest distance (discharge gap A ') connecting the discharge electrodes 27 and the inner cylinder 11 Are approximately the same distance. In the present embodiment, the discharge gaps A and A 'are set to about 15 to 18 mm, but are preferably set in consideration of the length and thickness of the discharge electrode 27, the magnitude of the applied voltage, and the like. . Note that "dividing the gap G into two equal parts" is a concept that allows not only the case of completely dividing into two equal parts, but also deviation about several millimeters radially outward or inward.

  Further, in a state where the electrostatic precipitator 1 is assembled, the tip of the air flow guide 24 is located on an extension extending vertically upward from the tip of each discharge electrode 27. That is, the tip of the air flow guide 24 is disposed at a position where the gap G is bisected. Further, a distance B between an extension line extending in parallel with the air flow guide 24 from the tip of each discharge electrode 27, and the air flow guide 24 is set longer than the discharge gaps A and A '. This can prevent the occurrence of corona discharge between each discharge electrode 27 and the air flow guide 24.

  As shown in FIG. 3, the assembled electrostatic precipitator 1 is housed in the housing frame 60 and connected to the upstream end of the exhaust pipe 61 via the connection guide 25. The electrostatic precipitator 1 is housed in the housing frame 60 in a posture in which the feeding insulator 13 is directed to the output terminal (not shown) of the high voltage power supply unit 17. The output terminal of the high voltage power supply unit 17 is in a state where the feeding coil spring 32 is compressed, and is electrically connected to the discharging unit 12 (each discharge electrode 27) via the feeding coil spring 32 and the feeding screw S3. (See Figure 1).

<High-voltage power supply unit>
As shown in FIG. 1, the high voltage power supply unit 17 includes a high voltage transformer 17A, a voltage doubling unit 17B, and a limit switch 17C. The high voltage power supply unit 17 applies a high voltage between the discharge electrodes 27 and the cylinders 10 and 11. The high voltage transformer 17A boosts the AC voltage of the main power source P (commercial power source). The voltage doubler 17B converts the AC voltage boosted by the high voltage transformer 17A into a DC voltage, and further boosts the voltage to generate a high voltage of about 5 kV. The voltage doubler 17B also functions as an output controller that controls application of a high voltage to the discharge electrode 27. The limit switch 17C is in the closed state (ON state) when the electrostatic precipitator 1 is mounted on the housing frame 60, and is in the open state (OFF state) when the electrostatic precipitator 1 is detached from the housing frame 60.

<Air flow path>
As shown in FIG. 3, an air flow path 15 is formed on the outside and the inside of the electrostatic precipitator 1. The air flow path 15 includes a first flow path 15A, a second flow path 15B, and a third flow path 15C.

  The first flow path 15 </ b> A is formed between the outer peripheral surface of the outer cylindrical body 10 and the side surface of the housing frame 60. The first flow path 15A extends in the up-down direction along the outer peripheral surface of the outer cylinder 10. In the first flow path 15A, air flows from the upper side to the lower side. The second flow passage 15B is formed to extend in the vertical direction between the inner peripheral surface of the outer cylinder 10 and the outer peripheral surface of the inner cylinder 11. In the second flow path 15B, the air reversed at the lower end (downstream end) of the first flow path 15A flows from the lower side to the upper side. The third flow path 15 </ b> C is formed to extend in the vertical direction inside the inner cylindrical body 11. In the third flow path 15C, air reversed at the upper end (downstream end) of the second flow path 15B flows downward from above. The downstream end of the third flow path 15 </ b> C is connected to the upstream end of the exhaust pipe 61.

  As described above, the air flow path 15 reverses the flow direction of the air twice at the downstream end of the first flow path 15A and the downstream end of the second flow path 15B. It is formed.

  Further, as shown in FIG. 4, the air flow path 15 includes a first opening 16A, a second opening 16B, and a third opening 16C.

  The first opening 16A is an opening at the upstream end of the second flow passage 15B. In detail, the first opening 16A is formed in a substantially annular shape by a gap between the lower end (the other end) of the outer cylinder 10 and the lower end (the other end) of the inner cylinder 11. More specifically, the first opening 16A is formed by a gap between an extension line extending parallel to the inclined surface of the connection guide 25 from the lower end of the outer cylinder 10 and the inclined surface of the connection guide 25. . The second opening 16B is an opening corresponding to the boundary between the downstream end of the second flow passage 15B and the upstream end of the third flow passage 15C. In detail, the second opening 16B is formed in a substantially annular shape (strip shaped in a substantially annular shape) by a gap between the end face 10A and the upper end (one end) of the inner cylindrical body 11. More specifically, the second opening 16B is formed in a band shape having a width corresponding to the length of a vertical line extending from the upper end of the inner cylindrical body 11 to the lower surface of the end face 10A. The third opening 16C is formed in a substantially circular shape by the open lower end of the inner cylinder 11 (see also FIG. 3).

  The first opening 16A, the second opening 16B, and the third opening 16C are formed to have substantially the same opening area. In other words, the opening area of each of the first opening 16A, the second opening 16B, and the third opening 16C is such that the flow velocity of air passing through the first to third openings 16A to 16C becomes constant. It is set. Note that “to make the flow velocity of air constant” is a concept that allows an error of ± several% to ± several tens%, as well as the case of making the flow velocity completely the same.

[Operation of electrostatic precipitator]
Next, the operation of the electrostatic precipitator 1 will be described.

  Air containing particles such as oil smoke generated from the food material burned by the cooking device is sucked into the housing frame 60 from the suction port of the cooking device by the suction force of the suction fan and flows toward the electrostatic precipitator 1. As shown in FIG. 3, air containing particles collides with the end face portion 10A provided on the upstream side in the flow direction and is slightly decelerated, and along the end face portion 10A and the first flow path 15A from the upper side to the lower side It flows toward.

  After the air containing the particles flows to the downstream end of the first flow path 15A, the flow direction is reversed (U-turned), and flows into the second flow path 15B (first opening 16A). At this time, since the air containing the particles is rapidly diverted from the first flow path 15A toward the second flow path 15B, the particles in the air having a relatively large particle size and a heavy weight (for example, droplets or the like) Fire powder etc.) is separated from air by centrifugal force etc. The separated particles fall into a collection unit 62 formed in the lower part of the housing frame 60 (around the exhaust pipe 61) and collected.

  Next, air containing particles flows from the lower side to the upper side along the second flow path 15B. The high voltage power supply unit 17 applies a high voltage between the discharge unit 12 disposed in the middle portion of the second flow passage 15B and the cylinders 10 and 11. Then, a corona discharge (negative polarity corona) is generated by an electric field generated around each discharge electrode 27.

  As shown in FIG. 4, the corona discharge forms a substantially conical charging area EA between the tip of each discharge electrode 27 and the outer cylinder 10. Further, the corona discharge forms a substantially conical charging area EA between the tip of each discharge electrode 27 and the inner cylindrical body 11. The corona discharge charges particles in the air flowing through the second flow passage 15B (charging area EA). The charged particles are attracted to and attracted to the inner peripheral surface of the outer cylinder 10 or the outer peripheral surface of the inner cylinder 11 which is a ground electrode. That is, particles in the air are separated from the air and collected on the surfaces of the cylinders 10 and 11.

  As shown in FIG. 3, the air flowing from the second flow path 15B (the first opening 16A) is air flowing between the outer cylinder 10 and the support cylinder 26, the inner cylinder 11 and the support cylinder It is diverted to the air flowing between them. The air having passed between the inner cylinder 11 and the support cylinder 26 passes the charging area EA generated by the discharge electrode 27 on the downstream side (upper side), and then the air flow guide on the downstream side of the second flow path 15B. The air flows along 24 and merges with the air that has passed between the outer cylinder 10 and the support cylinder 26. The combined air is directed radially outward by the air flow guide 24 so that it flows from the upper corner portion of the outer cylinder 10 along the end face portion 10A. For this reason, charged particles are collected in the vicinity of the upper corner portion of the outer cylinder 10 and on the inner surface (lower surface) of the end surface 10A (see FIG. 4). Since the air flow guide 24 is provided on the downstream side of the second flow path 15B so as to prevent the flow of air, the flow velocity of air is reduced in the middle portion of the second flow path 15B compared to the upstream and downstream sides. doing.

  Next, the air from which particles are separated flows to the downstream end of the second flow passage 15B, and then the flow direction is reversed (U-turned) to flow into the third flow passage 15C (second opening 16B) Do. The air flows downward from above along the third flow path 15C, and flows into the exhaust pipe 61 through the third opening 16C. The charged particles may be adsorbed also on the outer peripheral surface of the air flow guide 24 and the inner cylinder 11 (see FIG. 4).

  Thus, air from which particles have been removed is exhausted to the outside through the exhaust pipe 61. The particles collected by the collection unit 62 are periodically collected and removed from the collection unit 62. In addition, the particles collected in each of the cylindrical bodies 10 and 11 are removed at the time of periodic maintenance of the electrostatic precipitator 1. Specifically, the particles collected in each of the cylindrical bodies 10 and 11 are removed by performing ultrasonic cleaning or the like using an alkaline detergent on the electrostatic precipitator 1 taken out of the storage frame 60. .

  In the electrostatic precipitator 1 according to the embodiment described above, the particles in the air are charged in the process of passing through the charging area EA, and the inner peripheral surface of the outer cylinder 10, the inner surface of the end surface 10A, the inner cylinder It was collected on the outer peripheral surface of 11 and the inner peripheral surface of the inner cylinder 11. According to this configuration, substantially the entire inner surface of the outer cylindrical body 10 and substantially the entire surface of the inner cylindrical body 11 can be used as a particle collection area. Thereby, since the collection area can be expanded, the collection amount of particles can be increased.

  Further, in the electrostatic precipitator 1 according to the present embodiment, the air flow path 15 moves the air from the upper end (one end) to the lower end (the other end) along the outer peripheral surface of the end face portion 10A and the outer cylinder 10. After the circulation, the circulation direction of the air is reversed at the lower end side of the outer cylinder 10 so as to flow into the gap G between the outer cylinder 10 and the inner cylinder 11. Furthermore, after the air flow passage 15 circulates the air flowing into the gap G from the lower end side of the outer cylinder 10 from the lower end (the other end) to the upper end (one end), The flow direction is reversed to flow the inside of the inner cylinder 11 from the upper end to the lower end. That is, the air flow path 15 is folded inward at the outer lower portion of the outer cylindrical body 10 and is folded at the inner upper portion of the outer cylindrical body 10 to the inner side of the inner cylindrical body 11 to form a substantially S shape.

  According to the electrostatic precipitator 1, the air containing the particles makes a U-turn on the lower side of the outer cylinder 10, whereby the particles in the air having a relatively large particle size and heavy particles (for example, droplets or fire powder) Etc.) can be separated from the air. Therefore, air containing a large amount of particles is prevented from flowing into the charging area EA, and the amount (number) of particles adhering to the discharge electrode 27 can be reduced. Thereby, appropriate corona discharge can be generated over a long period of time. Further, by suppressing the inflow of droplets, fire powder, etc. into the electrostatic precipitator 1, it is possible to prevent the malfunction of the electrostatic precipitator 1 and the ignition within the electrostatic precipitator 1 and the exhaust pipe 61. it can. Further, for example, since it is not necessary to dispose a demister or a prefilter or the like for separating and removing particles in the air in the air flow path 15, the manufacturing cost of the electrostatic precipitator 1 can be reduced. Furthermore, since the discharge electrode 27 is provided inside the outer cylinder 10 to be the ground electrode, for example, it is possible to prevent an operator from accidentally touching the discharge electrode 27 at the time of maintenance or the like. . As a result, the worker can safely perform maintenance work and the like, and can also prevent the deformation and breakage of the discharge electrode 27.

  Further, in the electrostatic precipitator 1 according to the present embodiment, the outer cylindrical body 10 is provided in a posture in which the end face portion 10A is directed vertically upward. According to this configuration, the particles in the air can be efficiently separated from the air by the U-turn of the air containing the particles at the lower portion outside the outer cylinder 10. Further, inside the outer cylinder 10, the second flow path 15B extends upward from the lower side, so that the entry of particles to the charging area EA can be effectively inhibited.

  Further, according to the electrostatic precipitator 1 according to the present embodiment, the flow velocity of the air passing through the first to third openings 16A to 16C can be made substantially constant, so that the air flow path 15 is stabilized in its entirety. Airflow can be generated. Thus, particles in the air flowing through the air flow path 15 can be appropriately charged and collected.

  Further, in the electrostatic precipitator 1 according to the present embodiment, a part of air containing particles collides with the air flow guide 24 after passing through the charging area EA. According to this configuration, since the air flows along the air flow guide 24, the flow direction of the air can be directed to the outer cylindrical body 10 side. Specifically, air can be guided to a boundary portion (corner portion) between the inner peripheral surface of the outer cylindrical body 10 and the inner surface of the end surface portion 10A. Thereby, the area (collection area) for adsorbing and collecting charged particles can be further expanded, and the collection amount of particles can be further increased. Further, since the air flow guide 24 is provided to partially block the flow of air, the flow velocity of air can be reduced in the charging area EA. Thereby, particles in the air can be appropriately charged, and adsorption and collection of particles can be properly performed.

  Moreover, according to the electrostatic precipitator 1 which concerns on this embodiment, the outer cylinder 10, the inner cylinder 11, and the support cylinder 26 are arrange | positioned on the same axial center, and each discharge electrode 27 is an outer cylinder. The discharge gaps A and A 'of each discharge electrode 27 and the two ground electrodes (the outer cylinder 10 and the inner cylinder 11) can be made constant by being disposed substantially at the center of the gap G between 10 and the inner cylinder 11 Can be Thereby, it is prevented that only a part of the plurality of discharge electrodes 27 is extremely deteriorated, and stable corona discharge can be generated over the entire area in the circumferential direction.

  Further, according to the electrostatic precipitator 1 according to the present embodiment, since the fibrous line electrode 27A is used for the discharge electrode 27, corona discharge can be performed at a lower applied voltage than when a thick electrode is used. Can be generated. As a result, the generation of sparks can be suppressed, and the generation of ozone accompanying the ionization of air can also be suppressed. Further, since the discharge electrodes 27 are provided on both sides of the support cylinder 26 in the flow direction, the number of discharge electrodes 27 is increased as compared with the case where the discharge electrodes 27 are provided on one side of the support cylinder 26 in the flow direction. It can be done. As a result, the location of occurrence of corona discharge is increased, whereby particles in the air can be efficiently charged. Furthermore, since each discharge electrode 27 extends substantially in parallel with outer cylinder 10 (peripheral wall 10B) and inner cylinder 11, discharge gaps A and A are obtained even when each discharge electrode 27 is worn and shortened. Can be kept substantially constant. Thereby, stable corona discharge can be generated over a long period of time.

  Further, according to the electrostatic precipitator 1 according to the present embodiment, the inner cylindrical body 11 and the exhaust pipe 61 can be easily attached and detached via the connection guide 25. Thereby, the workability concerning cleaning and maintenance of the electric dust collector 1 and the exhaust pipe 61 can be improved.

  Moreover, in the electrostatic precipitator 1 which concerns on this embodiment, each insulator 13 and 14 was provided in the direction (radial direction) which interrupts | blocks circulation of air. According to this configuration, by supporting the support cylindrical body 26 on the outer cylindrical body 10 through the respective insulators 13 and 14, the discharge electrodes 27 are substantially parallel to the outer cylindrical body 10 and the inner cylindrical body 11. Can be opposed to Thereby, stable corona discharge can be generated.

  Further, in the electrostatic precipitator 1 according to the present embodiment, each of the insulators 13 and 14 includes the brim portion 30B formed so as to spread in parallel with the flow direction. According to this configuration, the creeping distance necessary for suppressing the creeping discharge can be secured by providing the flange portion 30B in each of the insulators 13 and 14. Thereby, the supply stop of the high voltage by the generation | occurrence | production of creeping discharge, the failure of the electrostatic precipitator 1, etc. can be suppressed.

First Modification
Next, with reference to FIG. 7, an electrostatic precipitator 2 according to a first modified example of the present embodiment will be described. FIG. 7 is a cross-sectional view showing an electrostatic precipitator 2 according to a first modification. In the following description, the same components as those of the above-described electrostatic precipitator 1 are denoted by the same reference numerals, and the same descriptions are omitted.

  The electrostatic precipitator 1 described above is provided in a posture in which the end face portion 10A of the outer cylinder 10 is directed vertically upward, but the electrostatic precipitator 2 according to the first modification is an end face of the outer cylinder 10 It is provided in a posture (lateral posture) in which the portion 10A is directed to the side (horizontal direction). In this case, the upstream end of the exhaust pipe 61 protrudes from the side surface of the housing frame 60 and is connected to the inner cylindrical body 11 (connection guide 25) of the electrostatic precipitator 2. In this case, air containing particles flows from the one end to the other end of the outer cylinder 10 (first flow path 15A) with the end face 10A side as the upstream, and the inner end at the outer other end of the outer cylinder 10 Make a U-turn. At this time, heavy particles having a relatively large particle size among particles in the air are separated from the air. Further, particles in the air are charged in the process of flowing from the other end toward the one end of the second flow path 15B, and are adsorbed and collected by the respective cylindrical bodies 10, 11. The air that has passed through the charging area EA makes a U-turn at the downstream end of the second flow passage 15B, flows into the third flow passage 15C, and is exhausted to the outside through the third flow passage 15C and the exhaust pipe 61.

  According to the electrostatic precipitator 2 according to the first modification of the embodiment described above, the same effects as those of the above-described electrostatic precipitator 1 can be obtained, such as reducing the amount of particles adhering to the discharge electrode 27 etc. You can get it.

  Further, in the electrostatic precipitator 2, the shapes of the insulator main body 41 and the support insulator 42 of the power supply insulator 40 are different from the shapes of the insulators 13 (30) and 14 of the above-described electrostatic precipitator 1.

  The forceps main body 41 includes an extension portion 41A, an outer connection portion 41B, and an inner connection portion 41C. The forceps main body 41 is integrally formed of porcelain or pottery. The extension portion 41A is formed to extend substantially in parallel with the flow direction of the second flow passage 15B. The outer connection portion 41B is formed to protrude radially outward from one end of the extension portion 41A. The inner connection portion 41C is formed to project radially inward from the other end of the extension portion 41A. That is, the forceps main body 41 is formed in a crank shape.

  Screw holes (not shown) are formed in the end face of the outer connecting portion 41B and the end face of the inner connecting portion 41C with which the feed screws S4 and S5 are engaged. The feed screw S4 is engaged with the screw hole of the outer connection portion 41B with the feed connection portion 31 interposed therebetween. The feed screw S5 penetrates the support cylinder 26 from the inside and meshes with the screw hole of the inner connection portion 41C. The insulator main body 41 is fixed to the outer cylinder 10 and the support cylinder 26 by the power supply screws S4 and S5. Further, in the insulator main body 41, a conductive wire 43 for conducting the feed screws S4 and S5 is incorporated. The high voltage power supply unit 17 and the support cylinder 26 (each discharge electrode 27) are electrically connected via power supply screws S4, S5 and a conductive wire 43.

  The supporting forceps 42 has substantially the same shape as the forceps main body 41, and includes an extending portion 42A, an outer connecting portion 42B, and an inner connecting portion 42C. The support forceps 42 is fixed to the outer cylindrical body 10 and the support cylindrical body 26 by the power supply screws S6 and S7. The conductive wire 43 is not built in the support insulator 42.

  According to the forceps main body 41 and the support forceps 42 described above, the creeping discharge can be effectively suppressed because a sufficient creeping distance is secured by providing the extension portions 41A and 42A. When assembling the electrostatic precipitator 2, after the insulator main body 41 and the supporting insulators 42 are screwed to the support cylindrical body 26, the support cylindrical body 26 may be inserted into the inside of the outer cylindrical body 10. In addition, the insulator main body 41 and the support insulator 42 may be adopted to the above-described electric dust collector 1.

Second Modified Example
Next, with reference to FIG. 8, an electrostatic precipitator 3 according to a second modification of the embodiment will be described. FIG. 8 is a cross-sectional view showing an electrostatic precipitator 3 according to a second modification. In the following description, the same components as those of the above-described electrostatic precipitator 1 are denoted by the same reference numerals, and the same descriptions are omitted.

  The electrostatic precipitator 3 according to the second modification includes a casing 50 that covers the outer side of the outer cylindrical body 10. The casing 50 is formed in a substantially bottomed cylindrical shape that closes the upper end surface and opens the lower end surface. The casing 50 sandwiches a gap with the outer cylinder 10 and is disposed on substantially the same axis as the outer cylinder 10. A suction port 51 for introducing air along the inner circumferential surface of the casing 50 is formed in the upper portion of the casing 50. The suction port 51 is formed to extend in the tangential direction (radial direction) from the outer peripheral surface of the casing 50.

  The air containing the particles flows into the casing 50 from the suction port 51 and falls while swirling in the first flow path 15A formed between the casing 50 and the outer cylinder 10. Particles in the air are separated from the air by centrifugal force in the process of moving in a spiral. The particles in the air are also separated from the air when making a U-turn from the downstream end of the first flow passage 15A toward the second flow passage 15B. The separated particles fall into the collection unit 62 and are collected.

  According to the electrostatic precipitator 3 according to the second modification of the embodiment described above, the particles in the air are generated by the centrifugal force generated by the swirling flow before the air containing the particles flows into the second flow path 15B. And heavy particles with relatively large particle sizes can be separated from air. As a result, it is possible to obtain the same effect as the above-described electrostatic precipitator 1, such as reducing the amount of particles adhering to the discharge electrode 27 or the like.

  In the electrostatic precipitators 1 to 3 according to the present embodiment (including the first and second modifications, the same applies to the following), a negative charging method is employed in which each discharge electrode 27 is used as a negative electrode to generate a negative corona. Although the present invention is not limited thereto. For example, a positive charging method may be employed in which positive discharge corona is generated with each discharge electrode 27 as a positive electrode. However, since the negative charge system can generate corona discharge at a lower voltage than the positive charge system, it is preferable to adopt the negative charge system. In addition, since the negative charging method has a lower frequency of occurrence of abnormal discharge and a smaller spark noise during abnormal discharge than the positive charging method, noise and the like can be suppressed during corona discharge.

  Further, in the electrostatic precipitators 1 to 3 according to the present embodiment, the outer cylindrical body 10, the inner cylindrical body 11, and the support cylindrical body 26 are each formed in a cylindrical shape, but the present invention is not limited thereto. . For example, the outer cylindrical body 10, the inner cylindrical body 11, and the support cylindrical body 26 may each be formed in a cylindrical shape having an elliptical cross section, or in an angular cylindrical shape having a polygonal cross section such as a triangle or a square. It may be formed. Moreover, although the outer cylinder body 10, the inner cylinder body 11, and the support cylinder 26 were stainless steel products, they may be formed with metals, such as not only this but iron, copper, aluminum alloy.

  Moreover, in the electrostatic precipitators 1 to 3 according to the present embodiment, the end face portion 10A of the outer cylinder 10 is formed in a flat plate shape, but the present invention is not limited to this. For example, although not shown, the end surface may be formed in a substantially conical shape, and may have a surface that inclines downward from above (downstream from the upstream in the flow direction). This can suppress the deposition of particles on the end face portion.

  Further, in the electrostatic precipitators 1 to 3 according to the present embodiment, the inner cylinder 11 is attached to the outer cylinder 10 via the four attachment plates 22, but the present invention is not limited to this. The inner cylinder 11 may be attached to the outer cylinder 10 via one or more attachment plates 22. The inner cylinder 11 is attached to the outer cylinder 10 (mounting plate 22) by the fixing nut N1 and the mounting screw S1, but instead, the inner cylinder 11 is attached by means such as adhesion with an adhesive or welding May be

  In the electrostatic precipitators 1 to 3 according to the present embodiment, the air flow guide 24 and the connection guide 25 are formed as separate members from the inner cylindrical body 11, but the present invention is not limited to this. For example, at least one of the air flow guide 24 and the connection guide 25 may be integrally formed with the inner cylinder 11. In addition, although the air flow guide 24 and the connection guide 25 are made of stainless steel, the invention is not limited to this, and a synthetic resin having heat resistance may be used.

  Further, in the electrostatic precipitators 1 to 3 according to the present embodiment, the discharge electrode 27 fixed to the upper part of the support cylinder 26 and the discharge electrode 27 fixed to the lower part of the support cylinder 26 are separated. The present invention is not limited to this. For example, the discharge electrode 27 may be formed to have a length penetrating vertically between the outer support cylindrical body 26A and the inner support cylindrical body 26B and protruding from both upper and lower ends of the support cylindrical body 26. . That is, the upper discharge electrode 27 and the lower discharge electrode 27 may be connected to one.

  Further, in the electrostatic precipitators 1 to 3 according to the present embodiment, the plurality of discharge electrodes 27 are arranged in the same phase in the upper portion and the lower portion of the support cylinder 26, but the present invention It is not limited. For example, as shown in FIG. 9, the plurality of discharge electrodes 27 fixed to the upper portion of the support cylinder 26 and the plurality of discharge electrodes 27 fixed to the lower portion of the support cylinder 26 are circumferentially 1 It may be shifted by 2 pitches. As a result, the charging area EA generated at the downstream (upper) discharge electrode 27 can compensate for the area where the upstream (lower) discharge electrode 27 can not generate the charged area EA.

  In the electrostatic precipitators 1 to 3 according to the present embodiment, the discharge electrode 27 is crimped to the outer support cylindrical body 26A and the inner support cylindrical body 26B, but the present invention is not limited to this. For example, the discharge electrode 27 may be bonded to the support cylinder 26 via an adhesive. Also, for example, the discharge electrode 27 may be implanted on the support cylinder 26 by electrostatic flocking processing. In addition, when using adhesion | attachment or electrostatic flocking processing, it is not necessary to form the support cylinder 26 in double structure with the outer side support cylinder 26A and the inner side support cylinder 26B. Further, each discharge electrode 27 is made of stainless steel, but is not limited to this, and may be formed of metal such as tungsten or titanium alloy.

  In the electrostatic precipitators 1 to 3 according to the present embodiment, the support cylinder 26 is supported by the outer cylinder 10 via the four insulators 13 and 14 (40, 42), but the present invention It is not limited to this. For example, the support cylinder 26 may be supported by the outer cylinder 10 by one feeding insulator 13, 40 and one supporting insulator 14, 42.

  The description of the above embodiment shows one aspect of the electrostatic precipitator according to the present invention, and the technical scope of the present invention is not limited to the above embodiment.

  The technique of the present invention can be used for a smokeless roaster or the like that sucks and collects oil smoke generated during cooking. Moreover, it can also be utilized for an air cleaner etc. which collect | recovers particle | grains, such as pollen in air, and smoke of a cigarette, indoors. Furthermore, it may also be used for an air supply duct device for taking in air into which air has been removed dust (particles) from air outside the room, and an exhaust duct for exhausting air for which air removed from dust (particles) from room air is discharged to the room outside. it can.

DESCRIPTION OF SYMBOLS 1 electrostatic precipitator 10 outer cylinder 10A end surface part 11 inner cylinder 13, 40 insulator for electric power feeding (instrument)
14, 42 Support forceps (forceps)
DESCRIPTION OF SYMBOLS 15 Air flow path 16A 1st opening 16B 2nd opening 16C 3rd opening 24 Air flow guide 25 Connection guide 26 Support cylinder 27 Discharge electrode 30B, 14B edge part 61 Exhaust pipe G Clearance

Claims (10)

An electrostatic precipitator for charging particles in air by corona discharge and collecting the particles,
An outer cylindrical body formed as a cylindrical ground electrode closed at one end by an end face and open at the other end;
An inner cylinder formed as a cylindrical ground electrode having open ends, and provided with a gap between an inner peripheral surface of the outer cylinder and the end surface portion inside the outer cylinder;
A plurality of discharge electrodes supported by a support cylinder provided in a state of being electrically insulated from the outer cylinder and the inner cylinder between the outer cylinder and the inner cylinder;
After the air flowing into the gap between the outer cylinder and the inner cylinder from the other end of the outer cylinder is circulated from the other end toward the one end, the air flow direction is reversed to turn the inner cylinder What is claimed is: 1. An electrostatic precipitator comprising: an air flow passage formed to circulate the inside of the body from one end to the other end. The end face portion is provided on the upstream side in the air flow direction,
The air flow path circulates air from one end to the other end along the end face portion and the outer peripheral surface of the outer cylinder, and then the flow direction of air is reversed to form the outer cylinder and the inside. The electrostatic precipitator according to claim 1, wherein the electrostatic precipitator is formed to flow into a gap with the cylinder.   The electrostatic precipitator according to claim 1 or 2, wherein the outer cylindrical body is provided in a posture in which the end face portion is directed vertically upward. The air flow path is
An annular first opening formed by a gap between the other end of the outer cylinder and the other end of the inner cylinder;
An annular second opening formed by a gap between the end face and one end of the inner cylinder;
And a third opening formed by the open other end of the inner cylinder,
The opening area of each of the first opening, the second opening and the third opening is such that the flow velocity of air passing through the first opening, the second opening and the third opening is constant. The electrostatic precipitator according to any one of claims 1 to 3, wherein the electrostatic precipitator is set as follows.   The electric current according to any one of claims 1 to 4, further comprising an air flow guide which is formed to be inclined to the downstream side in the air flow direction from one end of the inner cylindrical body to the outer side. Dust collector. The support cylinder is formed in a cylindrical shape with both ends open,
The outer cylinder, the inner cylinder, and the support cylinder are respectively disposed on the same axial center,
The electric dust collection according to any one of claims 1 to 5, wherein the discharge electrode is provided at a position that divides a gap between the outer cylinder and the inner cylinder into two equal parts. apparatus.   The discharge electrode is formed by bundling a plurality of fibrous line electrodes, and is provided in a state of extending from the support cylinder toward the upstream side and the downstream side in the flow direction of air. The electrostatic precipitator according to any one of claims 1 to 6.   The connection guide according to any one of claims 1 to 7, further comprising a connection guide which is formed so as to spread from the other end of the inner cylinder toward the downstream side in the flow direction of air and connects an exhaust pipe. Electric dust collector as described.   The insulator according to claim 1, further comprising: a ladder provided between the outer cylinder and the support cylinder so as to electrically insulate the outer cylinder from the support cylinder. Item 9. The electrostatic precipitator according to any one of Items 1 to 8.   10. The electrostatic precipitator according to claim 9, wherein the insulator includes a ridge portion formed to extend in parallel with the flow direction of air.

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