JP6097438B1 - Electrostatic liquid applicator - Google Patents

Abstract

When it becomes necessary to use another type of coating liquid, the oil type can be switched in a shorter time. First and second shims 17 and 19 are disposed between first and second nozzle blades 7 and 9, respectively. The first discharge flow path 21 is formed on the first nozzle 17 side of the first shim 17 and the first discharge port 11 is formed at the tip. A second discharge flow path 23 is formed on the second nozzle blade 9 side of the second shim 19, and a second discharge port 13 is formed at the tip. By opening the first electromagnetic valve 45 and driving the first pump 41, the first coating liquid 37 in the first coating liquid storage tank 33 is discharged from the first discharge port 11. By opening the second electromagnetic valve 47 and driving the second pump 43, the second coating liquid 39 in the second coating liquid storage tank 35 is discharged from the second discharge port 13. [Selection] Figure 1

Description

  The present invention applies a voltage having a polarity opposite to that of a material to be coated to a conductive member provided in a nozzle, and supplies a coating liquid supplied to a liquid flow path between the main body portion of the nozzle and the conductive member. The present invention relates to an electrostatic liquid coating apparatus that discharges from a discharge port of a nozzle while being charged to the same polarity as that of the liquid and adheres to a material to be coated.

  As a conventional electrostatic liquid applicator, one described in Patent Document 1 below is known. The electrostatic liquid coating apparatus of Patent Document 1 includes a shim between a pair of nozzle blades, and a discharge flow path is formed between the shim and one nozzle blade. A coating liquid supply flow path and a liquid tank are connected to the discharge flow path, and the coating liquid is supplied from the liquid tank via the coating liquid supply flow path.

JP 2006-150217 A

  By the way, in the above-described conventional electrostatic liquid coating apparatus, the coating liquid stored in the liquid tank is supplied into the nozzle through the coating liquid supply channel, and a kind of coating liquid is discharged from the discharge port. In this case, when it is necessary to apply another type of coating liquid to the material to be coated, the liquid tank is switched to a liquid tank that stores the other type of coating liquid and the coating liquid supply flow path. At that time, since the coating liquid used first remains in the discharge flow path and the coating liquid supply flow path in the nozzle, it is necessary to discharge the remaining coating liquid in order to prevent mixing of different coating liquids. is there. Since it takes a long time to discharge the coating liquid, the operation of switching the oil type becomes extremely complicated.

  Accordingly, an object of the present invention is to facilitate the operation of switching oil types when it is necessary to use another type of coating liquid.

The present invention comprises a pair of first and second nozzle blades made of an electrically insulating material and facing each other;
A first and second shim made of a conductive material and sandwiched between the pair of first and second nozzle blades; and an electrode for applying a voltage having a polarity opposite to the material to be coated to the first and second shims; , Provided between the surface of the first shim and the first nozzle blade, and provided between the first discharge channel through which the first coating liquid flows, and between the surface of the second shim and the second nozzle blade. A second discharge channel through which the second coating liquid flows, a first discharge port provided at a tip of the first discharge channel and through which the first coating liquid is discharged toward the material to be coated; A second discharge port that is provided at a tip of the second discharge flow path and discharges the second coating liquid toward the material to be coated, and is connected to the first discharge flow path and the second discharge flow path, respectively. a first coating liquid supply passage and a second coating liquid supply passage that, the first coating liquid and the second coating solution, respectively The first coating liquid storage tank and the second coating liquid storage tank, the first electromagnetic valve and the first pump provided in the first coating liquid supply flow path, and the second coating liquid supply flow path are provided. A second electromagnetic valve and a second pump; and a control device that drives and controls the first electromagnetic valve and the first pump and the second electromagnetic valve and the second pump. When the first pump is driven with the solenoid valve opened and the second solenoid valve closed, the first coating liquid in the first coating liquid storage tank is supplied with the first coating liquid. The second electromagnetic valve is opened and the first electromagnetic valve is closed by the control device after being discharged from the first discharge port through the flow path and the first discharge flow path and applied to the material to be coated. When the second pump is driven in a state, the second coating liquid storage tank has the second The coating liquid is discharged from the second discharge port through the second coating liquid supply channel and the second discharge channel and applied to the material to be coated, and the control device drives the first pump. The high voltage generator is continuously operated between a first state in which the first coating liquid is discharged and a second state in which the second pump is driven to discharge the second coating liquid, The first shim and the second shim are characterized in that a high voltage is continuously applied between the first state and the second state .

  According to the present invention, discharge channels are respectively formed on both sides of the shim in the nozzle so that different coating liquids can be supplied to the respective discharge channels. As a result, the oil type can be switched in a shorter time, and the oil type switching operation is facilitated.

1 is an overall configuration diagram of an electrostatic oil coating apparatus according to a first embodiment of the present invention. (A) is sectional drawing which shows the shim in the nozzle in the electrostatic type oiling apparatus of FIG. 1, (B) is a front view of the shim in which the discharge flow path was formed. FIG. 2 is a cross-sectional view around the connector pin of FIG. 1. It is sectional drawing of the nozzle concerning the 2nd Embodiment of this invention.

  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 the first embodiment of the present invention is made of a metal such as steel or aluminum, or a product made of other materials. An oil-based liquid (hereinafter simply referred to as “liquid”) as a conductive coating liquid such as lubricating oil, release oil, or food oil is applied to the surface of the oil-coated body 3 as a coating material.

  At this time, for example, the above-described oil-coated body 3 is conveyed in the left-right direction in FIG. 1 by a work conveyance device such as a conveyor device (not shown), and the electrostatic oil-coating device 1 is placed in the middle of the work conveyance device. Install. The liquid is sprayed from the nozzle 5 of the electrostatic oil coating apparatus 1 toward the surface of the oil-coated body 3 under the action of static electricity, and the oil-coated body 3 is instantaneously coated.

  The nozzle 5 includes a pair of first nozzle blades 7 and second nozzle blades 9 that face each other, and two first and second discharge ports 11, 9 are provided between the tips of the first and second nozzle blades 7, 9. 13 is provided. The first and second nozzle blades 7 and 9 are made of an electrically insulating material such as resin, and the width dimension in the direction orthogonal to the paper surface in FIG. 1 is larger than the width dimension in the same direction of the oil-coated body 3. doing.

  A shim 15 is disposed between the first and second nozzle blades 7 and 9. The shim 15 is sandwiched between the first and second nozzle blades 7 and 9. The shim 15 closely contacts the first shim 17 located on the first nozzle blade 7 side and the second shim 19 located on the second nozzle blade 9 side back to back. Both the first shim 17 and the second shim 19 are made of a conductive material such as stainless steel having a thickness of, for example, about 0.5 mm.

  On the surface of the first shim 17 on the first nozzle blade 7 side (one surface of the shim 15), a first discharge channel 21 having a first discharge port 11 at the tip is formed. On the surface of the second shim 19 on the second nozzle blade 9 side (the other surface of the shim 15), a second discharge channel 23 having a second discharge port 13 at the tip is formed. The first and second shims 17 and 19 can be used in the same way as shown in FIG.

  The first discharge channel 21 is etched on the surface of the first shim 17 on the first nozzle blade 7 side, for example, with a groove depth C as shown in FIG. Similarly, the second discharge flow path 23 is etched at a groove depth C on the surface of the second shim 19 on the second nozzle blade 9 side.

  As shown in FIG. 2 (B), the first shim 17 has two first discharge passages 21 formed along the longitudinal direction, and each has a triangular oil sump 21a and an oil sump portion 21a. And a continuous rectangular discharge portion 21b. Similarly, the second shim 19 includes a triangular oil reservoir 23a and a rectangular discharge portion 23b continuous to the oil reservoir 23a. The ends of the discharge portions 21b and 23b opposite to the oil sumps 21a and 23a correspond to the first and second discharge ports 11 and 13, respectively.

  The entire nozzle 5 is fixed to a support bracket (not shown) using a fixing bolt (not shown). In order to pass the fixing bolt, the first and second shims 17 and 19 have relatively large bolt insertion holes 17h and 19h in the vicinity of both side edges in the longitudinal direction.

  Corresponding to the bolt insertion holes 17h, 19h, bolt insertion holes (not shown) are also formed in the first and second nozzle blades 7, 9. Fixing bolts are respectively inserted into the bolt insertion holes 17h and 19h and a bolt insertion hole (not shown), and the entire nozzle 5 is fixed to a support bracket (not shown).

  In order to assemble the apparatus while maintaining liquid tightness between the first and second shims 17 and 19 and the first and second nozzle blades 7 and 9, a set screw (not shown) is used. Three relatively small screw insertion holes 17i and 19i are formed in the first and second shims 17 and 19 in order to pass the set screw. Corresponding to the screw insertion holes 17i, 19i, screw insertion holes (not shown) are also formed in the first and second nozzle blades 7, 9.

  As shown in FIG. 1, the first and second nozzle blades 7 and 9 are provided with first and second coating liquid supply ports 25 and 27, respectively. First and second coating liquid supply channels 29 and 31 are connected to the first and second coating liquid supply ports 25 and 27, respectively. First and second coating liquid storage tanks 33 and 35 are provided on the upstream side of the first and second coating liquid supply channels 29 and 31 opposite to the first and second coating liquid supply ports 25 and 27, respectively. ing. The first and second coating liquid storage tanks 33 and 35 contain first and second coating liquids 37 and 39 having different oil types, respectively.

  The first and second coating liquid supply passages 29 and 31 between the first and second coating liquid storage tanks 33 and 35 and the first and second coating liquid supply ports 25 and 27 are connected to the first from the upstream side. The second pumps 41 and 43 and the first and second electromagnetic valves 45 and 47 as flow path switching means are arranged, respectively. First and second coating liquid supply passages 29 and 31 between the first and second pumps 41 and 43 and the first and second electromagnetic valves 45 and 47, and the first and second coating liquid storage tanks 33, The first and second return solenoid valves 49 and 51 are disposed between the first and second return solenoid valves 35, respectively. The first and second return solenoid valves 49 and 51 keep the fluid pressure constant when the first and second pumps 41 and 43 are in operation, and the first and second pumps 41 and 43 It opens and closes to protect the liquid circuit.

  As shown in FIG. 1, a connector pin 53 is attached to the second nozzle blade 9 so as to protrude from the side surface. The connector pin 53 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 first and second shims 17 and 19.

  As shown in FIG. 3, the connector pin 53 is formed from the second nozzle blade 9 side from the pin insertion hole 9 a of the second nozzle blade 9, the pin insertion hole 19 a of the second shim 19, and the pin insertion hole 17 a of the first shim 17. And is provided with a shaft portion 53a and a head portion 53b having a larger diameter than the shaft portion 53a. A screw hole 7s is formed in the first nozzle blade 7 at a position corresponding to the pin insertion hole 9a. After the connector pin 53 is inserted from the screw hole 7s, the follow set screw 55 is screwed into the screw hole 7s.

  As a result, the head 53b of the connector pin 53 is pushed and fixed to the first shim 17 by the follow set screw 55, and the connector pin 53 comes into contact with the first shim 17 to contact the first and second shims 17, 19 is electrically conducted. As shown in FIG. 1, a high voltage generator 57 is connected to the connector pin 53 at a position protruding from the second nozzle blade 9 to the outside. Accordingly, a negative DC high voltage (around −60 to −80 kv) can be applied from the high voltage generator 57 to the first and second shims 17 and 19 via the connector pin 53.

  The first and second pumps 41 and 43, the first and second solenoid valves 45 and 47, the first and second return solenoid valves 49 and 51, and the high voltage generator 57 are driven and controlled by the control device 59. The first and second solenoid valves 45 and 47 and the first and second return solenoid valves 49 and 51 are always closed when not energized.

  Next, the oiling operation | work to the to-be-coated body 3 by the above-mentioned electrostatic type oiling apparatus 1 is demonstrated.

  When the first coating liquid 37 in the first coating liquid storage tank 33 is to be applied to the oil-coated body 3, the control device 59 energizes and opens the first electromagnetic valve 45, and the first pump 41. Drive. The second pump 43 remains stopped.

  By driving the first pump 41, the first coating liquid 37 in the first coating liquid storage tank 33 flows through the first coating liquid supply channel 29, and the first discharge channel in the nozzle 5 from the first coating solution supply port 25. 21. At this time, the control device 59 operates the high voltage generator 57 in advance, so that the above-described negative high DC voltage is applied to the first and second shims 17 and 19 via the connector pin 53. .

  The first coating liquid 37 that has flowed into the first discharge flow path 21 is instantaneously charged to a negative potential by the first and second shims 17 and 19 while passing through the first discharge flow path 21. In the first coating liquid 37 charged to a negative potential, charges having the same polarity repel each other, and the liquid is atomized as fine particles having a uniform particle diameter. The atomized fine particles 61 are discharged from the first discharge port 11. At this time, as shown in FIG. 1, a pair of inductor bars 63 charged to a positive potential are disposed on the left and right sides in front of the nozzle 5. As a result, the fine particles 61 charged to a negative potential are attracted to the inductor bar 63 and can be applied to the oil-coated body 3 while gradually spreading toward the oil-coated body 3.

  The application of the first coating liquid 37 to the oil-coated body 3 is completed, and then another oil-coated body 3 is continuously conveyed to the second oil-coated body 3 with respect to the second oil-coated body 3. A case where the second coating liquid 39 in the coating liquid storage tank 35 is applied will be described.

  In this case, the control device 59 stops the first pump 41 and stops energization of the first electromagnetic valve 45 to close it. On the other hand, the control device 59 energizes and opens the second electromagnetic valve 47 to drive the second pump 43. At this time, the controller 59 continuously operates the high voltage generator 57 from the time when the first pump 41 is driven to discharge the first coating liquid 37, and the high voltage is applied to the first and second shims 17. , 19 is applied continuously.

  By driving the second pump 43, the second coating liquid 39 in the second coating liquid storage tank 35 flows through the second coating liquid supply channel 31, and the second discharge channel in the nozzle 5 from the second coating solution supply port 27. 23. The second coating liquid 39 flowing into the second discharge flow path 23 is instantaneously charged to a negative potential by the first and second shims 17 and 19 while passing through the second discharge flow path 23. In the second coating liquid 39 charged to a negative potential, charges having the same polarity repel each other, and the liquid is atomized as fine particles having a uniform particle diameter. The atomized fine particles 65 are discharged from the second discharge port 13. The fine particles 65 are attracted to the pair of inductor bars 63 like the fine particles 61, and can be applied to the oil-coated body 3 while gradually spreading toward the oil-coated body 3.

  As shown in FIG. 1, the first discharge port 11 and the second discharge port 13 are displaced along the transport direction (the left-right direction in FIG. 1) of the oil-coated body 3. For this reason, the first discharge port 11 and the second discharge port 13 are displaced along the transport direction with respect to the pair of left and right inductor bars 63. That is, the first discharge port 11 is at a position close to the left inductor bar 63 in FIG. 1, and the second discharge port 13 is at a position close to the right inductor bar 63 in FIG.

  For this reason, the fine particles 61 discharged from the first discharge port 11 are displaced to the left in FIG. 1, and the fine particles 65 discharged from the second discharge port 13 are displaced to the right in FIG. However, since the first and second shims 17 and 19 have a thickness of about 0.5 mm as described above, the amount of displacement along the transport direction between the first and second discharge ports 11 and 13 is extremely large. The amount of displacement of the fine particles 61 and 65 to the left and right is very small.

  Accordingly, even if the first discharge port 11 and the second discharge port 13 are displaced along the transport direction, the fine particles 61 and 65 discharged from the first and second discharge ports 11 and 13 are oil-coated. The body 3 spreads almost evenly in the left-right direction in FIG. As a result, the coating liquid can be uniformly applied by the oil-coated body 3. When the fine particles 61 and 65 are ejected so as to be greatly displaced in one of the left and right directions in FIG. 1, the displaced side is applied thicker, which may cause uneven coating.

  According to the present embodiment, the first and second discharge channels 21 and 23 are formed on the surfaces of the first and second shims 17 and 19 on the first and second nozzle blades 7 and 9 side in the nozzle 5, respectively. Separate first and second coating liquids 37 and 39 can be supplied to the first and second discharge channels 21 and 23. At that time, the first and second electromagnetic valves 45 and 47 are controlled to be opened and closed, so that the first and second discharge channels 21 and 23 can be quickly switched to each other. The oil type between the coating liquids 37 and 39 can be switched in a shorter time, and the switching operation becomes extremely easy.

  When the oil type is switched from the first coating solution 37 to the second coating solution 39, it is not necessary to discharge the coating solution in the first discharge channel 21 and the first coating solution supply channel 29 that are used first, The first coating liquid 37 adhering to the first discharge port 11 after stopping the discharge is also released immediately after waiting for about 10 to 15 seconds. Therefore, the switching operation from the first coating liquid 37 to the second coating liquid 39 can be easily performed in a shorter time while suppressing the mixing of the first coating liquid 37 into the second coating liquid 39. Similarly, the switching operation from the second coating liquid 39 to the first coating liquid 37 can be easily performed in a shorter time.

  In the present embodiment, the shim 15 includes a first shim 17 located on the first nozzle blade 7 side and a second shim 19 located on the second nozzle blade 9 side. The surface of the first shim 17 and the first shim 17 A first discharge channel 21 is provided between the nozzle blade 7 and a second discharge channel 23 is provided between the surface of the second shim 19 and the second nozzle blade 9. In this case, the first discharge channel 21 and the second discharge channel 23 can be easily formed in one nozzle 5 while using the existing first shim 17 and second shim 19 having the same shape.

  FIG. 4 shows a nozzle 5A of an electrostatic oiling apparatus 1A according to the second embodiment of the present invention. The nozzle 5A of the second embodiment is made of the same material as the first and second nozzle blades 7 and 9 between the first shim 17 and the second shim 19 with respect to the nozzle 5 of the first embodiment. An insulating plate 67 is provided as an insulating member made of an electrically insulating material such as resin. The connector pin 53 passes through the insulating plate 67 and is in contact with the inner surface of the pin insertion hole 19a shown in FIG. Other configurations are the same as those of the first embodiment, and the same components as those of the first embodiment are denoted by the same reference numerals.

  Similarly to the first embodiment, in the second embodiment, the first and second discharge flows on the surfaces of the first and second shims 17 and 19 on the first and second nozzle blades 7 and 9 side in the nozzle 5A. The channels 21 and 23 are formed, respectively, so that the first and second coating liquids 37 and 39 can be supplied to the first and second discharge channels 21 and 23, respectively. At that time, the first and second electromagnetic valves 45 and 47 similar to those in FIG. 1 can be opened and closed to quickly switch to one of the first and second discharge flow paths 21 and 23. The oil type between the first and second coating liquids 37 and 39 can be easily switched in a shorter time.

  In the second embodiment, an insulating plate 67 made of an electrically insulating material is provided between the first shim 17 and the second shim 19. For this reason, the deviation | shift amount along the left-right direction in FIG. 4 of the 1st discharge port 11 and the 2nd discharge port 13 becomes large compared with 1st Embodiment by the part which provided the insulating plate 67. FIG. However, when the insulating plate 67 is a sheet-like thin film, the amount of deviation can be made substantially equal to that of the first embodiment.

  Therefore, also in the second embodiment, even if the first discharge port 11 and the second discharge port 13 are displaced in the left-right direction in FIG. 4, they are discharged from the first and second discharge ports 11 and 13, respectively. The fine particles spread substantially uniformly in the left-right direction in FIG.

  As mentioned above, although embodiment of this invention was described, these embodiment is only the illustration described in order to make an understanding of this invention easy, and this invention is not limited to the said embodiment. The technical scope of the present invention is not limited to the specific technical matters disclosed in the above embodiment, but includes various modifications, changes, alternative techniques, and the like that can be easily derived therefrom.

  For example, in the first embodiment shown in FIG. 1, the two first and second shims 17 and 19 are used as the shim 15. However, one shim can be used. One shim forms a first discharge channel 21 and a second discharge channel 23 on both sides, that is, the surface facing the first nozzle blade 7 and the surface facing the second nozzle blade 9, respectively. .

  When a single shim is used, the first discharge port 11 and the second discharge port 13 in the left-right direction in FIG. 1 are compared with the case where two first and second shims 17 and 19 are used. The amount of deviation along the line can be further reduced. Therefore, when a single shim is used, the fine particles 61 and 65 discharged from the first and second discharge ports 11 and 13 are more evenly distributed in the horizontal direction in FIG. Will spread.

  In the first embodiment described above, the connector pin 53 is inserted from the first nozzle blade 7 side provided with the screw hole 7s. However, a screw hole may be provided in the second nozzle blade 9, a pin insertion hole may be provided in the first nozzle blade 7, and the connector pin 53 may be inserted from the second nozzle blade 9 side where the screw hole is provided.

  In the first embodiment described above, the connector pin 53 penetrates the first and second shims 17 and 19 as shown in FIG. However, the first and second shims 17 and 19 may not be provided with the pin insertion holes 17a and 19a, and the tip of the connector pin 53 that penetrates the second nozzle blade 9 may be in contact with the second shim 19. . Alternatively, the connector pin 53 may be passed through the first nozzle blade 7 and the tip of the connector pin 53 may be brought into contact with the first shim 17.

  In the second embodiment of FIG. 4, when the connector pin 53 is configured not to penetrate the first and second shims 17 and 19, two connector pins 53 are used. One of the two connector pins 53 passes through the second nozzle blade 9 and the tip is brought into contact with the second shim 19, and the other one passes through the first nozzle blade 7 and the tip is passed through the second nozzle blade 9. One shim 17 is brought into contact. Thereby, a high voltage can be applied to the first and second shims 17 and 19 located on both sides of the insulating plate 67.

3 Oil-coated body (coating material)
7 First nozzle blade 9 Second nozzle blade 11 First discharge port 13 Second discharge port 15 Shim 17 First shim 19 Second shim 21 First discharge channel 23 Second discharge channel 29 First coating liquid supply channel 31 2nd coating liquid supply flow path 45 1st solenoid valve (flow path switching means)
47 Second solenoid valve (flow path switching means)
53 Connector pin (electrode)
67 Insulating plate (insulating member)

Claims (2)

A pair of first and second nozzle blades made of an electrically insulating material and facing each other;
A first and second shim made of a conductive material and sandwiched between the pair of first and second nozzle blades;
An electrode for applying a voltage having a reverse polarity to the material to be coated to the first and second shims;
A high voltage generator connected to the electrode for applying a high voltage to the first and second shims;
A first discharge channel provided between the surface of the first shim and the first nozzle blade, and through which the first coating liquid flows;
A second discharge flow path provided between the surface of the second shim and the second nozzle blade, through which a second coating liquid flows;
A first discharge port that is provided at a tip of the first discharge flow path and discharges the first coating liquid toward the material to be coated;
A second discharge port that is provided at a tip of the second discharge flow path and discharges the second coating liquid toward the material to be coated;
A first coating liquid supply channel and a second coating liquid supply channel respectively connected to the first discharge channel and the second discharge channel;
A first coating liquid storage tank and a second coating liquid storage tank in which the first coating liquid and the second coating liquid are respectively stored;
A first solenoid valve and a first pump provided in the first coating liquid supply channel;
A second solenoid valve and a second pump provided in the second coating liquid supply channel;
A control device for driving and controlling the first electromagnetic valve and the first pump, the second electromagnetic valve and the second pump, and the high voltage generator;
The first coating liquid in the first coating liquid storage tank when the first pump is driven by the control device with the first electromagnetic valve opened and the second electromagnetic valve closed. Is discharged from the first discharge port through the first coating liquid supply channel and the first discharge channel, and is applied to the material to be coated,
When the second pump is driven by the control device with the second electromagnetic valve opened and the first electromagnetic valve closed, the second coating liquid in the second coating liquid storage tank Is discharged from the second discharge port through the second coating liquid supply channel and the second discharge channel and applied to the material to be coated,
The controller is configured to drive between the first state in which the first pump is driven to discharge the first coating liquid and the second state in which the second pump is driven to discharge the second coating liquid. The high voltage generator is continuously operated, and the first shim and the second shim are continuously applied with the high voltage between the first state and the second state. An electrostatic liquid coating apparatus. The electrostatic liquid coating apparatus according to claim 1 , wherein an insulating member made of an electrically insulating material is provided between the first shim and the second shim.

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