JP3200784U - Electrostatic application nozzle - Google Patents

Abstract

An electrostatic coating nozzle that can satisfactorily ensure electrical continuity between shims when the end portions are brought into contact with each other is provided. A shim 33A provided with a discharge flow path 7A and a shim 33B provided with a discharge flow path 7B are sandwiched and fixed by a pair of nozzle blades 27 and 29 in a state where the end portions are abutted. A semicircular cutout is formed at the end of the shim to provide a circular conducting screw insertion hole 33h. A semicircular recess serving as a circular recess 33i is formed on the periphery of the semicircular cutout. The circular recess 33i accommodates the conduction washer 39, and the conduction set screw 41 is inserted into the conduction blade screw insertion holes 27e and 29e and the conduction screw insertion hole 33h and fastened to the nut 43. [Selection] Figure 3

Description

  The present invention relates to an electrostatic coating nozzle having a configuration in which a shim including a discharge channel is sandwiched between a pair of nozzle blades facing each other.

  The electrostatic coating nozzle is described in Patent Document 1 below, for example. A shim is sandwiched between a pair of nozzle blades, and liquid is discharged from the tip of the nozzle through a discharge passage formed on one surface of the shim. When discharging the liquid, a negative high voltage having a polarity opposite to that of the material to be coated is applied to the shim, and the conductive liquid supplied to the discharge flow path is charged to the same polarity as the shim while discharging the nozzle. It is discharged from and adhered to the material to be coated.

  At this time, the material to be coated is grounded and has a positive potential. On the other hand, since liquids charged to a negative potential repel each other with the same polarity, the liquid is atomized as fine particles having a substantially uniform particle diameter, and discharged from the nozzle discharge port toward the material of opposite polarity. Is done.

JP 2006-150217 A

  By the way, the discharge flow path is formed along the width direction of the shim, and if the size of the material to be coated changes, it may be necessary to change the width dimension of the shim. At this time, if the shim is designed and manufactured in accordance with the size of the material to be coated, the cost increases. Therefore, a plurality of types of shims having different width dimensions can be designed and manufactured in advance, and a plurality of types of shims can be appropriately combined to cope with the size of the material to be coated.

  At that time, the plurality of types of shims are sandwiched between a pair of nozzle blades in a state where the end portions in the width direction are butted together and fastened and fixed using screws. However, if the end portions are merely brought into contact with each other, the electrical continuity between the shims becomes insufficient, and it is difficult to ensure a high voltage across the plurality of types of shims.

  Then, this invention aims at ensuring the electrical continuity state of shims at the time of abutting edge parts mutually.

  The present invention comprises a pair of nozzle blades made of an electrically insulating material and facing each other, and a plurality of shims made of a conductive material and sandwiched between the pair of nozzle blades with the end portions in the width direction facing each other. A liquid discharge channel provided on one nozzle blade side surface of the plurality of shims to discharge toward the material to be coated, an electrode for applying a voltage having a polarity opposite to the material to be coated to the shim, A set screw for inserting the pair of nozzle blades into the through holes of the pair of nozzle blades and fixing the shim together with the shim, and a screw insertion hole provided at an end portion of the plurality of shims that face each other and into which the set screw is inserted. When the set screw is inserted into the through hole of the pair of nozzle blades and the screw insertion hole of the shim and is fastened and fixed, the set screw is inserted between the shim and the nozzle blade. It is characterized in that it and a conductive washer for electrically connecting the shims between abutted the ends with.

  According to the present invention, by tightening the set screw, the conduction washer is pressed against each shim whose end portions are brought into contact with each other, and the electric conduction between the shims is performed via the conduction washer. Thereby, the electrical continuity state between the shims can be secured satisfactorily, and the plurality of types of shims can be secured at a high voltage.

1 is an overall configuration diagram of an electrostatic oil coating apparatus including an electrostatic coating nozzle according to an embodiment of the present invention. It is a front view of the shim used for the electrostatic application nozzle of FIG. FIG. 3 is a cross-sectional view including a shim and a pair of nozzle blades corresponding to the AA cross section of FIG. 2. FIG. 3 is a front view showing a state where two shims of FIG. 2 are separated from each other. It is sectional drawing which decomposed | disassembled which shows the fastening structure of the butt | matching part of two shims of FIG. FIG. 3 is a cross-sectional view including a shim and a pair of nozzle blades corresponding to the BB cross section of FIG. 2.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, an electrostatic oil coating apparatus 1 as an electrostatic liquid coating apparatus according to this embodiment includes oil as a conductive coating liquid on the surface of an oil-coated body 3 as a material to be coated. Apply a system liquid (hereinafter simply referred to as a liquid). The oil-coated body 3 is a metal such as steel or aluminum, or a product made of other materials. The liquid is lubricating oil, release oil, or food oil.

  When oiling a liquid, for example, the object to be coated 3 is conveyed by a work conveying device such as a conveyor device (not shown), and the electrostatic oiling device 1 is installed in the middle of the work conveying device. A liquid is sprayed from the electrostatic coating nozzle (hereinafter simply referred to as a nozzle) 5 of the electrostatic oil coating apparatus 1 toward the surface of the oil coated body 3 under the action of static electricity to instantly apply the oil coated body. Apply oil to 3.

  The nozzle 5 is provided with a discharge flow path 7 serving as a liquid flow path for liquid to be discharged toward the oil-coated body 3, and the discharge flow path 7 serves as a liquid supply path via a liquid supply port 9. A liquid supply conduit 11 is connected. The liquid supply pipe 11 is provided with an electromagnetic valve 17 and a variable flow control valve 19 that are driven and controlled by a control device 13 together with a liquid motor 15 described later. The variable flow control valve 19 is for adjusting the flow rate of the liquid in the liquid supply line 11 and may not be provided.

  A liquid tank 21 is provided at the end of the liquid supply line 11 opposite to the liquid supply port 9. The liquid in the liquid tank 21 is sucked by the liquid pump 23 driven by the liquid motor 15 and sent to the discharge flow path 7 through the electromagnetic valve 17 and the variable flow control valve 19 described above. In addition, a relief valve 25 is provided in the liquid supply line 11 between the liquid pump 23 and the electromagnetic valve 17 to keep the fluid pressure constant and protect the liquid pump 23 and the liquid circuit.

  The nozzle 5 includes a nozzle head 30 having a first nozzle blade 27 and a second nozzle blade 29 constituting a pair of nozzle blades. In the nozzle head 30, a slit 31 is provided between the first nozzle blade 27 and the second nozzle blade 29, and a shim 33 including the discharge flow path 7 is disposed in the slit 31.

  The first and second nozzle blades 27 and 29 are made of, for example, an electrically insulating material such as an insulating plastic. For example, the length (width) in the direction perpendicular to the paper surface in FIG. Longer than that. The shim 33 is made of a conductive material made of, for example, a stainless steel sheet having a thickness in the left-right direction of about 0.5 mm in FIG. 1, and is disposed along a direction orthogonal to the paper surface in FIG. The two shims 33A and 33B as shown in FIG.

  As shown in FIG. 2, the shim 33A includes one discharge flow path 7A corresponding to the discharge flow path 7 of FIG. 1, and the shim 33B includes two discharge flow paths 7B corresponding to the discharge flow path 7 of FIG. It has. Therefore, the length (width) of the shim 33A in the left-right direction in FIG. 2 is approximately half of the length (width) of the shim 33B in the left-right direction in FIG. The discharge flow path 7 (7A, 7B) is etched at a groove depth C on one side of the shim 33 (33A, 33B) (left side in FIG. 1, front side of the paper in FIG. 2).

  The discharge flow path 7A includes a triangular oil sump 7Aa and a rectangular discharge part 7Ab continuous to the oil sump part 7Aa. Similarly, the discharge flow path 7B includes a triangular oil sump 7Ba and a rectangular discharge part 7Bb continuous to the oil sump part 7Ba.

  A plurality of liquid supply ports 9 shown in FIG. 1 are individually provided corresponding to the respective oil reservoirs 7Aa and 7Ba, and communicate with each other near the triangular apexes of the respective oil reservoirs 7Aa and 7Ba. The electromagnetic valve 17 and the variable flow control valve 19 are individually provided corresponding to the plurality of liquid supply ports 9. Therefore, by opening and closing the solenoid valve 17 on the upstream side of each discharge flow path 7A, 7B, the entire application width in the left-right direction in FIG. 2 (the direction orthogonal to the paper surface in FIG. 1) is reduced. It can be changed according to.

  Two circular convex portions 33Ab are formed at positions corresponding to the rectangular discharge portions 7Ab in the discharge flow path 7A. Similarly, two circular convex portions 33Bb are formed at positions corresponding to the two rectangular discharge portions 7Bb in the discharge flow path 7B. The protruding height of each of the convex portions 33Ab and 33Bb to the front side in FIG. 2 is substantially equal to the groove depth C. By providing the convex portions 33Ab and 33Bb, the rigidity of the shims 33A and 33B is increased, and deformation due to warpage during energization is suppressed.

  The shim 33A and the shim 33B abut end portions 33Aa and 33Ba in the width direction that face each other. In a state where the end portions 33Aa and 33Ba are in contact with each other, the interval between the discharge flow path 7A of the shim 33A and the discharge flow path 7B located on the shim 33A side of the shim 33B is the same between the two discharge flow paths 7B of the shim 33B. Approximately equal to the interval.

  The entire nozzle head 30 is fixed to a support bracket (not shown) using a fixing bolt (not shown). In order to pass the fixing bolt, a relatively large bolt insertion hole 33Ac is formed in the shim 33A at a position opposite to the shim 33B of the oil sump 7Aa. Similarly, in the shim 33B, a relatively large bolt insertion hole 33Bc is formed at a position opposite to the shim 33A of the oil sump 7Ba on the side away from the shim 33A.

  As shown in FIG. 3, bolt insertion holes 27a, 29a are also formed in the first and second nozzle blades 27, 29 corresponding to the bolt insertion holes 33Ac. Similarly, bolt insertion holes 27b and 29b are also formed in the first and second nozzle blades 27 and 29 corresponding to the bolt insertion holes 33Bc. Fixing bolts (not shown) are respectively inserted into the bolt insertion holes 27a, 29a, 33Ac and the bolt insertion holes 27b, 27b, 33Bc, and the entire nozzle head 30 is fixed to a support bracket (not shown).

  In order to assemble the apparatus while maintaining liquid tightness between the shim 33A and shim 33B and the first and second nozzle blades 27 and 29, a set screw 35 described later is used. In order to pass the set screw 35, the shim 33A is formed with one relatively small screw insertion hole 33Ad. The screw insertion hole 33Ad is located on the opposite side of the oil reservoir 7Aa to the discharge part 7Ab in the discharge flow path 7A.

  In order to pass the set screw 35, the shim 33B is formed with three relatively small screw insertion holes 33Bd. Two of the three screw insertion holes 33Bd are located on the opposite sides of the oil reservoir 7Ba to the discharge part 7Bb in the two discharge flow paths 7B. The remaining one screw insertion hole 33Bd is located between the oil reservoirs 7Ba in the two discharge flow paths 7B.

  As shown in FIG. 3, screw insertion holes 27c and 29c are formed in the first and second nozzle blades 27 and 29 corresponding to the screw insertion holes 33Ad. Similarly, screw insertion holes 27d and 29d are formed in the first and second nozzle blades 27 and 29 corresponding to the screw insertion holes 33Bd. A set screw 35 is inserted into the screw insertion holes 27c, 29c, 33Ad and the screw insertion holes 27d, 29d, 33Bd from the first nozzle blade 27 side. Each set screw 35 is fastened to a nut 37 on the second nozzle blade 29 side.

  Conductive blade screw insertion holes 27e and 29e as through holes are formed in the first and second nozzle blades 27 and 29 at positions corresponding to the butted portions of the end portions 33Aa and 33Ba of the shim 33A and the shim 33B. Yes.

  Corresponding to the blade blade insertion holes 27e, 29e for conduction, a conduction screw insertion hole 33h is formed at the abutting portion between the end portions 33Aa, 33Ba of the shim 33A and shim 33B. As shown in FIGS. 2 and 4, the conduction screw insertion hole 33h is constituted by semicircular cutouts 33Ah and 33Bh formed in the end portions 33Aa and 33Ba of the shim 33A and the shim 33B, respectively.

  Semicircular recesses 33Ai and 33Bi are respectively formed on the peripheral edges of the semicircular cutouts 33Ah and 33Bh serving as the conduction screw insertion holes 33h on the second nozzle blade 29 side. The two semicircular recesses 33Ai and 33Bi constitute one circular recess 33i. A conductive washer 39 is accommodated in one circular recess 33i.

  The thickness of the conductive washer 39 is 0.3 mm when the thickness of the shims 33A and 33B is 0.5 mm, and the depth of the two semicircular recesses 33Ai and 33Bi is 0.3 mm. When the thickness of the shims 33A and 33B is 0.3 mm, the thickness of the conductive washer 39 is 0.1 to 0.2 mm. In this case, the depth of the recesses 33Ai and 33Bi is 0.1 to 0.2 mm. And

  A conduction set screw 41 is inserted into the conduction blade screw insertion holes 27e and 29e and the conduction screw insertion hole 33h from the first nozzle blade 27 side and fastened to the nut 43 on the second nozzle blade 29 side. By fastening the conduction set screw 41, the conduction washer 39 is pressed against the bottom surfaces of the two semicircular recesses 33Ai and 33Bi. As a result, the shim 33 </ b> A and the shim 33 </ b> B are electrically connected via the conduction washer 39.

  The fastening and fixing with the conduction set screw 41 is an apparatus that maintains the liquid tightness between the shim 33A and shim 33B and the first and second nozzle blades 27 and 29, similarly to the set screw 35 described above. Has the function to assemble.

  As shown in FIG. 1, a connector pin 45 is attached to the second nozzle blade 29 so as to protrude from the side surface. The connector pin 45 constitutes a power connector as an electrode for applying a high voltage having a negative potential opposite to that of the oil-coated body 3 to the shims 33A and 33B.

  As shown in FIG. 6, the connector pin 45 is disposed through the pin insertion hole 33Ae of the shim 33A from the first nozzle blade 27 side, and includes a shaft portion 45a and a head portion 45b having a larger diameter than the shaft portion 45a. It has. A screw hole 27s is formed at a position corresponding to the pin insertion hole 33Ae of the first nozzle blade 27. After the connector pin 45 is inserted from the screw hole 27s, the follow set screw 47 is screwed into the screw hole 27s.

  As a result, the head portion 45b of the connector pin 45 is pushed and fixed to the shim 33A by the follow set screw 47, and the connector pin 45 comes into contact with and electrically conducts the shim 33A. Therefore, a negative DC high voltage (around −60 to −80 kv) is applied from a high voltage generator (not shown) to the shim 33A via the shaft portion 45a of the connector pin 45 protruding from the second nozzle blade 29. It becomes possible to do.

  The shim 33B is also provided with a pin insertion hole 33Be for attaching another connector pin 45, but the connector pin 45 is not attached at a position corresponding to the pin insertion hole 33Be. The connector pin 45 may be attached to a position corresponding to one of the pin insertion hole 33Ae of the shim 33A and the pin insertion hole 33Be of the shim 33B.

  Next, the operation of this embodiment will be described.

  When assembling the nozzle head 30, the shim 33A, 33B is disposed between the first and second nozzle blades 27, 29 as shown in FIG. 3, and corresponds to the screw insertion holes 33Ad, 33Bd in FIG. At the position, the four set screws 35 are fastened. Further, one conduction set screw 41 is fastened at a position corresponding to the conduction screw insertion hole 33h in FIG.

  By fastening the set screw 35 and the conduction set screw 41, the shims 33A and 33B are pressurized while being sandwiched between the first and second nozzle blades 27 and 29, and the liquid tightness of the discharge flow paths 7A and 7B is maintained. Is done.

  Furthermore, when the conduction set screw 41 is fastened, the conduction washer 39 accommodated in the recess 33 i is sandwiched between the shims 33 </ b> A and 33 </ b> B and the second nozzle blade 29 and pressed. At that time, the conductive washer 39 comes into contact with the shims 33A and 33B in a pressed state, and becomes a conductive member that electrically connects the shims 33A and 33B. As a result, the electrical continuity between the shims 33A and 33B is ensured satisfactorily, and the plurality of types of shims 33A and 33B can be easily secured at a high voltage.

  In addition, the shims 33A and 33B of the present embodiment are provided with a recess 33i in which the conductive washer 39 is accommodated at the periphery of the semicircular cutouts 33Ah and 33Bh. In this case, when the conduction set screw 41 is fastened, the conduction washer 39 is accommodated in the recess 33i, so that the second nozzle blade 29 and the shims 33A and 33B are more reliably in close contact with each other and are liquid-tight. Can be held more securely.

  At this time, by making the depth of the recess 33 i equal to the thickness of the conductive washer 39, the adhesion between the second nozzle blade 29 and the shims 33 A and 33 B can be further enhanced.

  In the above-described embodiment, the shim 33A having one discharge flow path 7A and the shim 33B having two discharge flow paths 7B are butted against each other, but the shims having one discharge flow path are butted together. Alternatively, shims having two discharge flow paths may be abutted with each other. Further, another shim may be disposed between the shim 33A and the shim 33B.

3 Oil-coated body (coating material)
5 Electrostatic coating nozzle 7, 7A, 7B Discharge flow path 27 First nozzle blade 27e, 29e Blade screw insertion hole (through hole) for conduction
29 Second nozzle blade 33A, 33B Shim 33Aa, 33Ba Shim end 33Ah, 33Bh Semi-circular cutout 33h Conductive screw insertion hole 39 Conductive washer 41 Conductive set screw 45 Connector pin (electrode)

Claims (3)

A pair of nozzle blades made of an electrically insulating material and facing each other;
A plurality of shims made of a conductive material and sandwiched between the pair of nozzle blades in a state where the end portions in the width direction are abutted with each other;
A liquid discharge flow path provided on the surface of one of the plurality of shims on the nozzle blade side for discharging toward the material to be coated;
An electrode for applying a voltage having a polarity opposite to that of the material to be coated to the shim;
A set screw for conduction that fixes the pair of nozzle blades together with the shim inserted into the through holes of the pair of nozzle blades;
A semi-circular cutout provided at an end portion of the plurality of shims that face each other and serving as a conduction screw insertion hole into which the conduction set screw is inserted;
When the conducting set screw is inserted into the through hole of the pair of nozzle blades and the conducting screw insertion hole of the shim and fastened and fixed, the conductive blade is located between the shim and the nozzle blade. A conduction washer that electrically connects the shims that have been inserted with a set screw and abutted against each other;
An electrostatic coating nozzle characterized by comprising:   The electrostatic coating nozzle according to claim 1, wherein the shims that are abutted with each other are provided with a recess in the periphery of the semicircular cutout in which the conductive washer is accommodated.   The electrostatic coating nozzle according to claim 2, wherein a depth of the concave portion is equal to a thickness of the conductive washer.

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