JP2008290046A - Electrostatic coating equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the amount of paint discarded at the time of applying a conductive paint and the use amount of a cleaning liquid, to shorten the cleaning time and improve the coating efficiency.
SOLUTION: A recovery valve 51 for recovering paints remaining in first and second discharge flow paths 29 and 32 in respective tanks 6 and 18 after the completion of coating is provided. Therefore, for example, pressurized air from the pressurized air source 25 is supplied to the first discharge channel 29 by the recovery valve 51, and the remaining paint in the first discharge channel 29 is recovered in the first tank 6. Then empty the interior to make it insulated. Similarly, the remaining paint in the second discharge flow path 32 can also be collected in the second tank 18. On the other hand, the paint line 60 including the supply flow path 45, the pump unit 47, the coating machine 3 and the like is washed by the washing valve 57 after the painting is finished. Thereby, the quantity of the coating material discarded can be reduced and the range to wash | clean can be decreased.
[Selection] Figure 2

Description

  The present invention relates to an electrostatic coating apparatus suitable for use in applying a high voltage to a conductive paint such as a water-based paint and spraying it on an object to be coated.

  2. Description of the Related Art Generally, an electrostatic coating apparatus for coating an object to be coated includes a coating machine that sprays a charged paint to which a high voltage is applied by direct charging, and is configured to supply the paint from a paint source to the coating machine. . In this case, in a direct charging electrostatic coating device that directly applies a high voltage to a conductive paint having a low electrical resistance such as an aqueous paint, the high voltage applied to the paint is prevented from leaking to the ground potential. There is a need to. Therefore, this type of electrostatic coating apparatus is configured to open (cut) the ground portion between the coating machine and the paint source during the painting operation. That is, during the painting operation, the paint source side such as a tank is floated with respect to the ground potential.

  Here, the electrostatic coating apparatus of the prior art is provided with two systems for supplying paints, each of which includes a liquid reservoir for temporarily storing paint from a paint source and a hose for discharging the paint from the liquid reservoir. Is configured to be selectively connected to an electrostatic spray gun via another hose by a coil selection manifold (see, for example, Patent Document 1).

JP-A-2-2885

  When coating is performed using the electrostatic coating apparatus according to Patent Document 1, one liquid reservoir is connected to the electrostatic spray gun via the other hose by a coil selection manifold. In this state, the paint in one liquid reservoir is supplied to the electrostatic spray gun via a hose, another hose, etc., and sprayed from the electrostatic spray gun toward the object to be coated.

  Further, when painting is performed using one liquid reservoir, the other liquid reservoir can be filled with the next color paint in parallel. In this case, the paint remaining in the hose between the liquid reservoir and the coil selection manifold is discharged, and the adhered paint is washed. As a result, the other liquid reservoir can be electrically opened (cut) from the paint supply line extending from one liquid reservoir to the electrostatic spray gun, so that a high voltage applied to the paint leaks from the other liquid reservoir to the ground potential. Can be prevented.

  By the way, the electrostatic coating apparatus according to Patent Document 1 described above does not discharge the paint remaining in the hose between the liquid reservoir and the coil selection manifold every time the one liquid reservoir and the other liquid reservoir are switched. Must not. Moreover, the paint adhering in the hose must be washed with a washing solvent every time the paint is switched.

  For this reason, in the electrostatic coating apparatus of Patent Document 1, the amount of paint that is wasted from the hose increases, and the amount of cleaning solvent used also increases. As a result, the cleaning operation takes time and the amount of the cleaning solvent used increases, resulting in a problem that the coating efficiency is lowered and the coating cost is increased.

  The present invention has been made in view of the above-described problems of the prior art, and the object of the present invention is to reduce the amount of paint discarded and the amount of cleaning liquid used when performing a painting operation using a conductive paint such as an aqueous paint. Thus, an object of the present invention is to provide an electrostatic coating apparatus capable of shortening the cleaning time and improving the coating efficiency.

  In order to solve the above-described problem, an electrostatic coating apparatus according to the invention of claim 1 is provided with a spraying means for applying a high voltage to a supplied paint and spraying it toward an object to be coated, and two independent storages for storing the paint. First and second tanks comprising containers, first and second filling passages for filling the first and second tanks with paint from a paint source, and storage in the first and second tanks A first and a second discharge flow channel for discharging the applied paint, a supply flow channel having one end joined to and connected to the first and second discharge flow channels, and the other end connected to the spraying means, A discharge flow path switching valve that is connected to the first and second discharge flow paths and the supply flow path, and connects the first and second discharge flow paths to the supply flow path; The first discharge channel is connected to the second discharge channel, and is switched from one discharge channel to the other by the discharge channel switching valve. A recovery valve for supplying pressurized air from a pressurized air source to the one discharge flow path and a connection to the supply flow path for recovering the remaining paint in the discharge flow path to the one tank. After the painting operation by the spraying means is completed, pressurized air from a pressurized air source and cleaning liquid from a cleaning liquid source are supplied to clean the paint remaining in the supply flow path and the spraying means. A cleaning valve, and an earth switch that is provided in each of the first and second tanks and supplies the paint to the spraying means for painting work. It becomes.

  According to a second aspect of the present invention, the recovery valve includes a first recovery air supply valve provided between the pressurized air source and the first discharge flow path, the pressurized air source, and a second And a second recovery air supply valve provided between the discharge flow path.

  According to a third aspect of the present invention, the first and second filling passages are switched to the one tank after being switched from the one discharge passage to the other discharge passage by the discharge passage switching valve. A filling valve for filling the paint and an exhaust valve for discharging the air in the tank when the tank is filled with the paint by the filling valve are provided.

  According to a fourth aspect of the present invention, there is provided a paint extrusion valve for supplying pressurized air from a pressurized air source into the first and second tanks to extrude the paint filled in the first and second tanks. It is configured.

  According to a fifth aspect of the present invention, the first and second tanks are formed as containers using an insulating material, and the upper high-voltage cutoff chamber is formed in the container by a two-compartment defining plate having a paint circulation hole. And a lower paint storage chamber, and an upper portion of the container has a paint inlet through which the paint flows into the paint storage chamber from the high voltage shut-off chamber through the paint flow hole of the two-compartment defining plate. And a paint outlet for discharging the paint in the paint containing chamber is provided on the lower side of the container.

  According to a sixth aspect of the present invention, there is provided a recovery flow path having one end branched from the middle of the discharge flow path and the other end communicated with the paint-accommodating chamber of the tank. A tank outflow valve that is located between the tank and the tank and opens when supplying the paint toward the spraying means, and the recovery passage is opened when the paint is recovered toward the tank. A tank recovery valve is provided.

  The electrostatic coating apparatus according to the invention of claim 7 includes a spray means for applying a high voltage to the supplied paint and spraying it toward the object to be coated, and two independent containers for storing the main component of the two-component paint. Stored in the first and second tanks, the first and second tanks, the first and second tanks filled with the main agent from the main agent source, and the first and second tanks. The first and second discharge flow paths for discharging the main agent, the main agent supply flow path having one end joined to and connected to the first and second discharge flow paths, and the other end connected to the spraying means; A discharge flow path switching valve that is connected to the first and second discharge flow paths and the main agent supply flow path, and connects the first and second discharge flow paths to the main agent supply flow path; and The first and second discharge channels are connected to each other, and the one after the first discharge channel is switched to the other by the discharge channel switching valve. A recovery valve for supplying pressurized air from a pressurized air source to the one discharge flow path and a main agent supply flow path for recovering the remaining main agent in the discharge flow path to one tank. In order to clean the main agent remaining in the main agent supply flow path and the spraying means after the completion of the painting operation by the spraying means, the pressurized air from the pressurized air source and the cleaning liquid from the cleaning liquid source are used. The main tank side cleaning valve to be supplied and the one tank which is provided in each of the first and second tanks and supplies the main agent to the spray means for painting work are opened (cut) to the ground. An earth switch, one end connected to the curing agent source of the two-component paint, and the other end joined to the supply channel, and provided in the curing agent supply channel. Select a curing agent, pressurized air for cleaning, and cleaning liquid to It becomes constituted by the selective supply valve for supplying toward the unit.

  In the first aspect of the invention, first, in the painting process using the first tank, the first tank is filled with the paint from the paint source through the first filling channel. Next, the discharge flow path switching valve is switched so as to connect the first discharge flow path to the supply flow path. In this state, the paint is supplied from the first tank to the spraying means via the first discharge flow path and the supply flow path, and the paint is sprayed from the spraying means toward the object to be coated.

  Also, in the painting process using the first tank, the first tank is opened (cut) with respect to the ground potential by the first ground switch, and then a high voltage is applied to the paint sprayed from the spraying means. To do. Thereby, for example, even when applying a water-based paint or a metallic paint having a low electric resistance value, it is possible to prevent a high voltage from leaking through the paint and to perform good electrostatic painting. On the other hand, in the painting process using the first tank, the second tank can be filled with paint.

  When the coating of the paint filled in the first tank is completed, the paint remaining in the first discharge flow path is collected in order to electrically insulate the inside of the first discharge flow path. In this recovery operation, the second discharge flow path is connected to the supply flow path by the discharge flow path switching valve, and then the pressurized air from the pressurized air source is supplied to the first discharge flow path by the recovery valve. Thereby, the remaining paint in the first discharge channel can be collected in the first tank, and the first discharge channel can be emptied to be in an insulated state. In parallel with this recovery operation, the paint filled in the second tank is supplied to the supply channel to prepare for painting.

  Next, in the painting process using the second tank, the second tank is opened (cut) with respect to the ground potential by the second earth switch, and a high voltage is applied to the paint sprayed from the spraying means. In this state, by supplying the paint in the second tank to the spraying means via the second discharge channel and the supply channel, the paint can be sprayed from the spraying unit toward the object to be coated. it can.

  Next, after finishing the painting operation, the paint remaining in the supply flow path and the spraying means is washed. In this cleaning operation, the cleaning valve supplies pressurized air from the pressurized air source and cleaning liquid from the cleaning liquid source to the supply channel and the spraying means. Thereby, the coating material remaining in the supply flow path and the spraying means can be washed.

  As a result, the paint in the discharge channel can be recovered by being pushed back into the tank by the pressurized air from the pressurized air source, so that the amount of the discarded paint can be reduced. Further, since the cleaning range is only the liquid contact surface of the supply channel and the spraying means, the amount of cleaning liquid used can be reduced, and the cleaning time can be shortened. Thereby, improvement of painting efficiency, reduction of painting cost, etc. can be aimed at.

  In the second aspect of the invention, when the paint remaining in the first discharge flow path is recovered, the first recovery air supply valve is opened. Thereby, the pressurized air from the pressurized air source can be supplied to the first discharge flow path, and the paint in the first discharge flow path is pushed by this pressurized air, and the inside of the first tank Can be recovered.

  Further, when recovering the paint remaining in the second discharge flow path, the second recovery air supply valve is opened and pressurized air is supplied to the second discharge flow path, whereby the second The paint in the discharge channel can be collected in the second tank.

  In the invention of claim 3, when one of the first and second tanks is filled with the paint, the discharge passage switching valve switches the other discharge passage to the supply passage, and then the filling is performed. The filling valve provided in the flow path is opened. Thereby, the paint from the paint source can be filled into one tank through the filling channel. Further, when filling the paint, by opening the exhaust valve, the air corresponding to the paint filling amount can be discharged from the tank, and the paint filling operation can be performed smoothly.

  According to the fourth aspect of the present invention, when the paint is applied, pressurized air from the pressurized air source is supplied into the tank by the paint extrusion valve. Thereby, the coating material in a tank can be extruded with pressurized air, and can be supplied to the spraying means side.

  In the invention of claim 5, the paint from the paint source flows into the tank from the paint inlet, passes through the upper high voltage shut-off chamber, passes through the paint flow hole of the two-compartment defining plate, and stores the lower paint. The chamber is filled. Moreover, the tank which accommodated the coating material in the coating material storage chamber is formed as a container using an insulating material. As a result, the paint filled in the paint storage chamber can be insulated from the paint source by the high voltage shut-off chamber, and the high voltage applied to the paint can be grounded via the filling channel and the paint source. Leakage can be prevented.

  In addition, since the two-compartment defining plate that partitions the inside of the container can prevent the paint in the paint containing chamber from flowing into the high-voltage shut-off chamber, the insulation performance by the high-voltage shut-off chamber can be maintained. And the coating material in a coating material storage chamber can be supplied to a spraying means via a discharge flow path etc. from a lower coating material outlet.

  According to the sixth aspect of the present invention, when the paint contained in the paint containing chamber of the tank is to be applied, the tank outflow valve is opened and the paint is supplied to the spraying means through the discharge passage. On the other hand, when the tank recovery valve is opened, the paint remaining in the discharge flow path can be recovered in the tank, and the amount of paint discarded can be reduced. In addition, after the paint in the discharge channel is collected, the tank can be electrically disconnected from the spraying means, so that the paint to be used next can be filled with the tank grounded.

  In the invention of claim 7, the curing agent supplied from the selective supply valve can be mixed with the main ingredient including the pigment, and the two-component paint can be applied. Further, the selective supply valve can clean the remaining two-component paint by supplying the pressurized air for cleaning and the cleaning liquid to the spraying means.

  Hereinafter, as an electrostatic coating apparatus according to an embodiment of the present invention, an electrostatic coating apparatus provided with a rotary atomizing head type coating machine will be described as a representative example and described in detail with reference to the accompanying drawings.

  First, FIG. 1 to FIG. 6 show a first embodiment of the present invention.

  In FIG. 1, reference numeral 1 denotes a direct charging type electrostatic coating apparatus according to the first embodiment. The electrostatic coating apparatus 1 performs coating by directly applying a high voltage to, for example, a water-based paint, a solvent-based metallic paint containing a metal pigment, and the like. The electrostatic coating apparatus 1 includes a coating robot 2, a coating machine 3, tanks 6 and 18, filling channels 21 and 22, discharge channels 29 and 32, supply channels 45, and discharge channels, which will be described later. The switching valve 48, the recovery valve 51, the cleaning valve 57, the earth switches 58 and 59, etc. are roughly configured.

  Here, the tanks 6, 18, the paint source 19, the pressurized air source 25, the cleaning liquid source 55, the filling valves 35 and 38, which will be described later, associated with the tanks 6 and 18, 39, the paint push-out valves 37 and 40, the tank outflow valves 41 and 43, and the tank recovery valves 42 and 44 are positions out of the operating range of the painting robot 2 so as not to disturb the painting, for example, the painting line Are arranged together on the wall surface of the wall. In addition, the pump unit 47, the discharge flow path switching valve 48, the recovery valve 51, and the cleaning valve 57 are located close to the coating machine 3, for example, on the horizontal arm 2C of the coating robot 2, in order to suppress waste of paint and cleaning liquid. Are arranged together.

  Reference numeral 2 denotes a painting robot which forms an operation part of the electrostatic coating apparatus 1. The painting robot 2 includes a base 2A, a vertical arm 2B that is rotatable and swingable on the base 2A, and a horizontal arm 2C that is swingably provided at the tip of the vertical arm 2B. And a wrist 2D provided at the tip of the horizontal arm 2C.

  Reference numeral 3 denotes a rotary atomizing head type painting machine provided on the wrist 2D of the painting robot 2, and the painting machine 3 constitutes a spraying means according to the present invention. Here, the coating machine 3 is composed of a main body 3A provided with an air motor therein, and a rotary atomizing head 3B provided at the tip of the main body 3A. The rotary atomizing head 3 </ b> B is supplied with paint via a supply channel 45 described later. Further, as shown in FIG. 2, a high voltage generator 5 (denoted as “HV” in FIGS. 2 and 3) is connected to the coating machine 3 via a high voltage cable 4. A high voltage can be applied directly to the sprayed paint.

  Next, the overall configuration including the specific internal structure of the first and second tanks 6 and 18 will be described.

  That is, 6 is a first tank constituting the electrostatic coating apparatus 1. As shown in FIGS. 2 and 3, the first tank 6 is provided independently of a second tank 18 described later, and stores the paint supplied from the paint source 19. In this case, the amount of paint stored in the first tank 6 is, for example, a storage amount for one vehicle that is required to be shared by a plurality of coating apparatuses and applied to the outer plate of one automobile body, for example, The amount of storage is about 200 to 1000 cc. Further, the first tank 6 is made of an insulating material such as polytetrafluoroethylene (PTFE), polyacetal (POM), polypropylene (PP), polyethylene (in order to prevent high voltage from leaking to the paint source 19 side. It is formed as a container using a resin material such as PE), a glass material, a ceramic material, or the like.

  Specifically, as shown in FIG. 4, the first tank 6 includes a container main body 7 composed of a cylindrical tube portion 7A extending upward and downward, an upper lid portion 7B, and a lower bottom portion 7C, and the container. It is configured as a container whose interior is divided into an upper part and a lower part by a two-compartment defining plate 8 provided by reducing the diameter of the upper and lower intermediate parts of the cylindrical part 7A of the main body 7. The inside of the container body 7 is defined by a two-chamber defining plate 8 into an upper high-voltage cutoff chamber 9 and a lower paint storage chamber 10.

  Here, as will be described later, when the paint in the first discharge flow path 29 is recovered, pressurized air is used, so that the two-chamber defining plate 8 is added to the recovered paint passage 17 which will be described later. Pressurized air is separated from paint containing pressurized air. That is, the two-compartment defining plate 8 returns the paint from which the pressurized air has been separated to the lower paint chamber 10, and passes only the separated pressurized air to the high voltage cutoff chamber 9 side through the central paint circulation hole 8A. It is to be distributed.

  Further, the lid 7B of the container body 7 has a paint inlet 11 through which the paint flows into the paint storage chamber 10, an exhaust port 12 through which the air that has flowed in the paint is discharged, and a paint from the paint storage chamber 10. And an air inflow port 13 through which pressurized air for extruding the air is supplied. Further, a filling nozzle 14 extending downward from the paint inlet 11 and an annular protrusion 15 surrounding the filling nozzle 14 are provided on the lower surface side of the lid portion 7B. The annular protrusion 15 increases the insulation distance between the paint chamber 10 and the tip of the filling nozzle 14 and prevents creeping discharge. On the other hand, the bottom portion 7C of the container body 7 has a funnel shape with a lowered central portion, and a paint outlet 16 is provided at the central portion.

  Further, a recovered paint passage 17 is provided in the cylinder portion 7 </ b> A of the container body 7 near the two-chamber defining plate 8 at an upper position of the paint storage chamber 10. As shown in FIG. 5, the recovered paint passage 17 is formed so as to communicate with the inner peripheral surface of the cylinder portion 7A in a tangential direction, and the paint flowing into the paint storage chamber 10 flows along the inner surface of the cylinder portion 7A. It can be returned to the storage chamber 10.

  Reference numeral 18 denotes a second tank provided independently of the first tank 6. Since the configuration of the second tank 18 is the same as that of the first tank 6 described above, the same reference numerals as those of the first tank 6 are used and description thereof is omitted.

  Next, a filling system including the paint source 19, the paint control valve 20, the first and second filling channels 21, 22 and the first and second air discharge channels 23, 24 will be described.

  A paint source 19 supplies paint to the electrostatic coating apparatus 1. Reference numeral 20 denotes a paint control valve (described as “CV1” in FIGS. 2 and 3) for controlling the supply pressure of the paint supplied by pressure from the paint source 19. The paint source 19 and the paint control valve 20 are used in common for both the first tank 6 and the second tank 18.

  Reference numeral 21 denotes a first filling flow path for filling the first tank 6 with paint. One end of the first filling channel 21 is connected to the paint source 19 via the paint control valve 20. On the other hand, the other end of the first filling passage 21 is connected to the paint inlet 11 of the first tank 6 via a first filling valve 35 described later.

  Reference numeral 22 denotes a second filling flow path for filling the second tank 18 with paint. One end of the second filling flow path 22 joins the first filling flow path 21 and is connected to the paint source 19 via the paint control valve 20. On the other hand, the other end of the second filling flow path 22 is connected to the paint inlet 11 of the second tank 18 via a second filling valve 38 described later.

  Reference numeral 23 denotes a first air discharge passage for discharging air from the first tank 6. One end of the first air discharge passage 23 is connected to the exhaust port 12 of the first tank 6 via a first exhaust valve 36 described later, and the other end is opened to the atmosphere.

  Reference numeral 24 denotes a second air discharge passage for discharging air from the second tank 18. One end of the second air discharge passage 24 is connected to the exhaust port 12 of the second tank 18 via a second exhaust valve 39 described later, and the other end is opened to the atmosphere.

  Next, the pressurized air source 25 for supplying pressurized air to the first and second tanks 6 and 18, the first pressure regulator 26, the first and second extruded air flow paths 27 and 28, etc. will be described.

  Reference numeral 25 denotes a common pressurized air source that supplies pressurized air to each part of the electrostatic coating apparatus 1. Reference numeral 26 denotes a first pressure regulator (described as “PR1” in FIGS. 2 and 3) for adjusting the supply pressure of the pressurized air supplied by the pressurized air source 25. Here, the pressurized air supplied from the pressurized air source 25 includes extrusion air for extruding the paint in the first and second tanks 6 and 18 to the supply flow path 45 side, and first and second described later. The recovery air for recovering the paint in the first and second tanks 6 and 18 and the cleaning air for cleaning the supply passage 45 and the coating machine 3 are used in common. . The first pressure regulator 26 is used in common for both the first tank 6 and the second tank 18.

  Reference numeral 27 denotes a first extrusion air passage for supplying pressurized air (extrusion air) for extruding the paint from the first tank 6. One end of the first extrusion air flow path 27 is connected to the pressurized air source 25 via the first pressure regulator 26. On the other hand, the other end of the first extrusion air passage 27 is connected to the air inlet 13 of the first tank 6 via a first paint extrusion valve 37 described later.

  Reference numeral 28 denotes a second extrusion air passage for supplying pressurized air (extrusion air) for extruding the paint from the second tank 18. One end of the second extruded air flow path 28 joins the first extruded air flow path 27 and is connected to the pressurized air source 25 via the first pressure regulator 26. On the other hand, the other end of the second extrusion air passage 28 is connected to the air inlet 13 of the second tank 18 via a second paint extrusion valve 40 described later.

  Next, the first and second discharge channels 29 and 32, the first and second recovery channels 30 and 33, and the like will be described.

  Reference numeral 29 denotes a first discharge passage for discharging the paint stored in the first tank 6. One end of the first discharge passage 29 is connected to the paint outlet 16 of the first tank 6 via a first tank outflow valve 41 described later. On the other hand, the other end of the first discharge channel 29 is connected to the supply channel 45 via a discharge channel switching valve 48 described later.

  Reference numeral 30 denotes a first recovery flow path. One end of the first recovery flow path 30 branches from a branch position 31 of the first discharge flow path 29, and the other end is connected via a first tank recovery valve 42. It is connected to the recovered paint passage 17 provided in the first tank 6.

  Reference numeral 32 denotes a second discharge passage for discharging the paint stored in the second tank 18. One end of the second discharge flow path 32 is connected to the paint outlet 16 of the second tank 18 via a second tank outflow valve 43 described later. On the other hand, the other end of the second discharge flow path 32 is connected to the supply flow path 45 via a discharge flow path switching valve 48 described later.

  Reference numeral 33 denotes a second recovery flow path. One end of the second recovery flow path 33 is branched from the branch position 34 of the second discharge flow path 32 and the other end is connected via the second tank recovery valve 44. The recovered paint passage 17 provided in the second tank 18 is connected.

  Next, the configuration of various valves provided in the upper part of the first tank 6 for filling and discharging the paint will be described.

  Reference numeral 35 denotes a first filling valve provided in the first filling channel 21. The first filling valve 35 closes the first tank outflow valve 41, opens the first exhaust valve 36, and then opens the first filling valve 35, thereby allowing the paint from the paint source 19 to flow. The first tank 6 is filled through the path 21. In addition, when performing the coating using the second tank 18 continuously after the coating using the first tank 6, prior to the opening of the first filling valve 35, a discharge flow path switching valve 48, which will be described later, The supply channel 45 is switched from the first discharge channel 29 to the second discharge channel 32.

  Reference numeral 36 denotes a first exhaust valve provided in the first air discharge passage 23. When the first filling valve 35 is opened and the first tank 6 is filled with the paint, the first exhaust valve 36 is opened together so that the paint flows in Air is discharged outside. The exhaust valve 36 is also opened when the paint is collected in the first tank 6.

  Reference numeral 37 denotes a first paint extrusion valve provided in the first extrusion air flow path 27. The first paint push-out valve 37 is opened to supply pressurized air from the pressurized air source 25 to the first tank 6 when coating is performed using the paint in the first tank 6. The paint filled in the inside is extruded toward the first discharge channel 29 side.

  Here, as shown in FIG. 1, the first filling valve 35, the first exhaust valve 36, and the first paint push-out valve 37 described above are collectively arranged on the upper side of the first tank 6, for example. .

  Next, the configuration of various valves provided in the upper part of the second tank 18 for filling and discharging the paint will be described.

  Reference numeral 38 denotes a second filling valve provided in the second filling flow path 22. Reference numeral 39 denotes a second exhaust valve provided in the second air discharge passage 24. Further, reference numeral 40 denotes a second paint extrusion valve provided in the second extrusion air flow path 28. The second filling valve 38, the second exhaust valve 39, and the second paint extrusion valve 40 are the same as the first filling valve 35, the first exhaust valve 36, and the first paint extrusion valve 37 described above. For example, they are arranged together on the upper side of the second tank 18.

  Next, the configuration of various valves provided in the lower part of the first tank 6 for supplying and collecting the paint will be described.

  41 is a first tank outflow valve (referred to as “tank” in FIG. 2) located between the branch position 31 of the first recovery flow path 30 and the first tank 6 and provided in the first discharge flow path 29. "Is abbreviated as" T outflow valve "). The first tank outflow valve 41 is opened when the paint stored in the paint storage chamber 10 of the first tank 6 is supplied toward the coating machine 3.

  Reference numeral 42 denotes a first tank recovery valve provided in the first recovery flow path 30 (“tank” is omitted from FIG. 2 and described as “T recovery valve”). The first tank recovery valve 42 opens together with the first exhaust valve 36 when recovering the paint remaining in the first discharge flow path 29 toward the first tank 6.

  Next, the configuration of various valves provided in the lower part of the second tank 18 for supplying and collecting the paint will be described.

  43 is a second tank outflow valve ("T" in FIG. 2) that is located between the branch position 34 with the second recovery flow path 33 and the second tank 18 and provided in the second discharge flow path 32. Spill valve ”). Reference numeral 44 denotes a second tank recovery valve (described as “T recovery valve” in FIG. 2) provided in the second recovery flow path 33. The second tank outflow valve 43 and the second tank recovery valve 44 are configured in the same manner as the first tank outflow valve 41 and the first tank recovery valve 42 described above.

  Next, a discharge system from the first and second discharge flow paths 29 and 32 to the coating machine 3 will be described.

  Reference numeral 45 denotes a supply flow path whose one end is connected to a joining position 46 between the first discharge flow path 29 and the second discharge flow path 32. The other end of the supply channel 45 extends to the coating machine 3 via a pump unit 47 and the like which will be described later. Here, a synthetic resin tube or the like having high electrical insulation is used for the supply channel 45, and a metal wire is knitted around the outer periphery of the synthetic resin tube to provide a shield ground. This shield earth is discharged to the ground when a high voltage is applied to the paint flowing through the supply channel 45 during electrostatic coating and the supply channel 45 breaks down due to this high voltage. To do.

  A pump unit 47 is provided in the supply channel 45. The pump unit 47 is a positive displacement gear pump 47A (denoted as “GP” in FIG. 3) for supplying a constant amount of paint, and opens and closes in synchronization with the gear pump 47A. It is comprised by the trigger valve 47B which performs supply and a stop. Further, the gear pump 47A is connected to a servo motor for rotational driving via a shaft (not shown) made of an insulating material, and is electrically disconnected from the servo motor connected to the ground potential.

  Next, the discharge flow path switching valve 48 for switching between the two paint supply systems will be described.

  The discharge flow path switching valve 48 is provided at a joining position 46 between the first and second discharge flow paths 29 and 32 and the supply flow path 45. The discharge flow path switching valve 48 switches and connects one of the first discharge flow path 29 and the second discharge flow path 32 to the supply flow path 45. The discharge flow path switching valve 48 includes a first valve body 48A provided in the first discharge flow path 29 and a second valve body 48B provided in the second discharge flow path 32. ing. Here, each valve body 48A, 48B always communicates with each recovery air supply valve 51B, 51C of the recovery valve 51, which will be described later, and each discharge flow path 29, 32 via a bypass passage.

  Next, a collection system for collecting the paint remaining in the discharge channels 29 and 32 in the tanks 6 and 18 will be described.

  Reference numeral 49 denotes a recovery air passage for supplying recovery air to the discharge passages 29 and 32. One end of the recovery air flow path 49 is connected to the pressurized air source 25 via a second pressure regulator 50 (described as “PR2” in FIGS. 2 and 3). On the other hand, the other end of the recovery air passage 49 is branched into a first air passage 49B and a second air passage 49C at a branch position 49A. The first air flow path 49 </ b> B is connected to the first discharge flow path 29 via the recovery air supply valve 51 </ b> B of the recovery valve 51 and the first valve body 48 </ b> A of the discharge flow path switching valve 48. The second air flow path 49 </ b> C is connected to the second discharge flow path 32 via the recovery air supply valve 51 </ b> C of the recovery valve 51 and the second valve body 48 </ b> B of the discharge flow path switching valve 48.

  Reference numeral 51 denotes a recovery valve provided at a branch position 49 </ b> A of the recovery air flow path 49. The recovery valve 51 is connected to the first and second discharge flow paths 29 and 32 via the discharge flow path switching valve 48. Further, the recovery valve 51 switches the supply flow path 45 to the first discharge flow path 29 by the discharge flow path switching valve 48, and then supplies the pressurized air from the pressurized air source 25 to the second discharge flow path 32. Supply. On the other hand, the recovery valve 51 switches the supply flow path 45 to the second discharge flow path 32 by the discharge flow path switching valve 48 and then supplies the pressurized air from the pressurized air source 25 to the first discharge flow path 29. Supply.

  The recovery valve 51 includes a gate valve 51A provided in the recovery air channel 49 upstream of the branch position 49A, a first recovery air supply valve 51B provided in the first air channel 49B, The second recovery air supply valve 51C is provided in the second air flow path 49C.

  Next, a cleaning system for cleaning between the cleaning fluid switching valve 52 and the coating machine 3 will be described.

  A cleaning fluid switching valve 52 selectively supplies pressurized air (cleaning air) and cleaning liquid. The cleaning fluid switching valve 52 includes a cleaning air supply valve 52A connected to the pressurized air source 25 via a third pressure regulator 53 (described as “PR3” in FIGS. 2 and 3), and a cleaning liquid control valve. The cleaning liquid supply valve 52B is connected to the cleaning liquid source 55 through 54 (described as “CV2” in FIGS. 2 and 3).

  Reference numeral 56 denotes a cleaning fluid flow path having one end connected to the cleaning fluid switching valve 52. The other end of the cleaning fluid channel 56 is connected to a joining position 46 between the discharge channels 29 and 32 and the supply channel 45.

  A cleaning valve 57 is provided in the middle of the cleaning fluid flow path 56. The washing valve 57 is used to wash the adhering paint remaining in a paint line 60 described later including the supply flow path 45, the pump unit 47, the paint machine 3 and the like after the painting work by the painting machine 3 is completed. The cleaning valve 57 is opened to supply pressurized air (cleaning air) from the pressurized air source 25 and cleaning liquid from the cleaning liquid source 55 toward the supply channel 45, the coating machine 3, and the like. can do.

  Further, first and second ground switches 58 and 59 for opening the first and second tanks 6 and 18 with respect to the ground potential during the painting operation will be described.

  Reference numeral 58 denotes a first earthing switch provided in electrical connection with the first tank 6. The earth switch 58 is configured as a normally closed contact, and is opened when a signal is input from the outside. The first earth switch 58 is normally closed (connected). On the other hand, the first tank 6 is connected to the supply flow path 45 via the first discharge flow path 29 by the discharge flow path switching valve 48 and opened (cut) in the painting process using the first tank 6, The first tank 6 is electrically disconnected from the ground. Thereby, even when the high voltage applied to the coating material through the main body 3A of the coating machine 3 is transmitted to the coating material in the first tank 6, it can be prevented from leaking to the ground. Further, the first earth switch 58 can be closed except for the painting work, and the first tank 6 can be connected to the earth.

  Reference numeral 59 denotes a second earth switch provided in electrical connection with the second tank 18. The second ground switch 59 has a configuration similar to that of the first ground switch 58 described above and a similar function to the second tank 18.

  Reference numeral 60 denotes a paint line including the supply flow path 45, the pump unit 47, the coating machine 3, and the like. The paint line 60 sprays the paint from the rotary atomizing head 3 </ b> B of the coating machine 3 by distributing the paint from the first and second discharge flow paths 29 and 32 during painting. On the other hand, at the time of cleaning, the paint remaining inside can be cleaned with cleaning air and cleaning liquid.

  The electrostatic coating apparatus 1 according to the first embodiment has the above-described configuration. Next, a painting operation and a cleaning operation by the electrostatic coating apparatus 1 will be described with reference to a time chart shown in FIG. .

  First, a painting operation using the first and second tanks 6 and 18 alternately will be described. For convenience of explanation, the first tank 6 is filled with paint, the second tank 18 is used and empty, and the paint filling process to the second tank 18 is performed in parallel. Will be explained on the condition.

  In the painting process using the first tank 6, the first tank outflow valve 41 is opened in order to secure a paint distribution path, and the first tank 6 (first The discharge channel 29) is connected to the supply channel 45. Further, in order to extrude the paint in the first tank 6, the first paint extrusion valve 37 is opened and the first exhaust valve 36 is opened. Further, by opening the first ground switch 58, the first tank 6, the first tank outflow valve 41, the first tank recovery valve 42 and the like are brought into a cut-off state separated from the ground potential. In the first tank 6, the high voltage cutoff chamber 9 electrically blocks the paint in the paint storage chamber 10 from the first filling channel 21 (the paint source 19 side).

  Further, the rotary atomizing head 3B of the coating machine 3 is driven to rotate, a high voltage is applied to the paint by the high voltage generator 5, the trigger valve 47B of the pump unit 47 is opened, and the gear pump 47A is driven. As a result, the coating machine 3 atomizes the coating material supplied from the supply flow path 45 and causes the coating material particles to fly along the lines of electric force formed with the object to be coated (not shown). Paint can be painted.

  On the other hand, in the paint filling process to the second tank 18 performed in parallel with the painting process by the first tank 6 described above, the paint is filled in the second tank 18 where the paint has decreased in the previous painting process. Is. In the paint filling process into the second tank 18, the second filling valve 38 and the second exhaust valve 39 are opened. As a result, the paint from the paint source 19 is filled into the second tank 18 via the second filling channel 22. In addition, when the paint is filled, the second exhaust valve 39 is opened, and air corresponding to the filling amount can be released from the second air discharge passage 24, so that the paint can be filled efficiently in a short time. Can do.

  Next, when the painting process by the first tank 6 is completed, the process moves to a paint collecting process for collecting the paint remaining in the first discharge flow path 29 in the first tank 6. In the paint recovery process to the first tank 6, the recovery valve 51 is switched so that the recovery air flow path 49 passes through the first discharge body 29 (the first discharge body 29 A of the discharge flow path switching valve 48). 1 tank 6). In this state, the first tank recovery valve 42 and the first exhaust valve 36 are opened. As a result, the paint remaining in the first discharge flow path 29 is pushed toward the first tank 6 by the pressurized air supplied from the pressurized air source 25, so that the paint is recovered in the first collection. It can be recovered from the recovered paint passage 17 through the flow path 30 into the first tank 6. After the paint in the first discharge channel 29 is collected, no conductive paint remains in the first discharge channel 29, so that the paint in the first tank 6 is applied. The high voltage applied to the machine 3 can be cut off.

  At the time of collecting the paint, the collected paint passage 17 flows in a tangential direction along the inner surface of the first tank 6, so that scattering due to collision with the inner surface, generation of bubbles, and the like can be prevented. Further, although the pressurized air is mixed in the collected paint, the pressurized air is separated by the two-chamber defining plate 8 and the paint flows down to the paint containing chamber 10, and the pressurized air passes through the paint circulation hole. The air flows out to the high voltage cutoff chamber 9 side through 8A, and the pressurized air can be discharged to the outside from the first air discharge channel 23.

  Here, when the paint recovery process to the first tank 6 described above is performed, a paint preparation process using the second tank 18 is performed in parallel. In the coating preparation process of the second tank 18, the second tank 18 (second discharge flow path 32) is connected to the supply flow path 45 by the discharge flow path switching valve 48. Further, in order to extrude the paint in the second tank 18, the second paint extruding valve 40 and the second tank outflow valve 43 are opened, and the pump unit 47 and the rotary atomizing head 3B of the coating machine 3 are opened. Drive for a predetermined time. Then, the paint in the second tank 18 is supplied to the rotary atomizing head 3B through the second discharge channel 32 and the supply channel 45. Thereby, when the gear pump 47A of the pump unit 47 is driven, since a predetermined amount of paint is supplied to the rotary atomizing head 3B, the next painting operation can be started immediately.

  Next, when the painting preparation process of the second tank 18 is completed, a painting process using the second tank 18 is performed. The painting process using the second tank 18 is substantially the same as the painting process using the first tank 6 described above. That is, in the painting process using the second tank 18, the second tank outflow valve 43 is opened, and the second tank 18 (second discharge flow path 32) is connected to the supply flow path 45 by the discharge flow path switching valve 48. And the second paint extrusion valve 40 is opened. Further, the second earth switch 59 is opened, and the second tank 18, the second tank outflow valve 43, the second tank recovery valve 44, and the like are cut off from the ground potential.

  Then, the rotary atomizing head 3B of the coating machine 3 is rotationally driven, a high voltage is applied to the paint by the high voltage generator 5, the gear pump 47A of the pump unit 47 is driven, and the trigger valve 47B is opened. Thereby, it is possible to apply the coating to the object using the paint of the second tank 18.

  On the other hand, in the paint filling process to the first tank 6 performed in parallel with the painting process by the second tank 18 described above, the first filling valve 35 and the first exhaust valve 36 are opened, and the paint is applied. The paint from the source 19 is filled into the first tank 6 through the first discharge channel 29.

  Next, when the painting process by the second tank 18 is completed, the process proceeds to a paint collecting process for collecting the paint remaining in the second discharge flow path 32 to the second tank 18. In the paint recovery process to the second tank 18, the recovery valve 51 is switched to connect the recovery air passage 49 to the second discharge passage 32, and the second tank recovery valve 44 and the second exhaust valve 39 are connected. And open the valve. Thereby, the paint remaining in the second discharge flow path 32 can be collected in the second tank 18 by the pressurized air supplied from the pressurized air source 25.

  On the other hand, when the painting operation using the first and second tanks 6 and 18 alternately is completed, the supply flow path 45 and the pump unit 47 are performed in parallel with the paint recovery process to the second tank 18 described above. The cleaning process of the paint line 60 including the coating machine 3 is performed. In the cleaning process of the paint line 60, the cleaning valve 57 is opened, and the cleaning air supply valve 52A and the cleaning liquid supply valve 52B of the cleaning fluid switching valve 52 are alternately opened. Then, the rotary atomizing head 3B and the pump unit 47 are driven. As a result, the coating material remaining and adhering to the coating line 60 including the supply flow path 45, the pump unit 47, and the rotary atomizing head 3B can be cleaned using cleaning air and cleaning liquid.

  In the time chart according to the embodiment shown in FIG. 6, the case where the coating is performed by using the first and second tanks 6 and 18 once is illustrated. However, it goes without saying that the first and second tanks 6 and 18 may be used twice or three times according to the shape of the painted surface, the painted area, etc., and then moved to the cleaning process.

  As described above, according to the first embodiment, the paints remaining in the first and second discharge flow paths 29 and 32 after completion of the coating process by the first and second tanks 6 and 18 are respectively A recovery valve 51 for recovery is provided in the tanks 6 and 18. Therefore, for example, by supplying pressurized air from the pressurized air source 25 to the first discharge channel 29 by the recovery valve 51, the remaining paint in the first discharge channel 29 becomes the first tank 6. The conductive paint in the first discharge channel 29 can be emptied and electrically insulated. Similarly, the remaining paint in the second discharge flow path 32 can also be collected in the second tank 18 to make the second discharge flow path 32 electrically insulated. Further, in the cleaning operation after the coating operation, it is only necessary to clean the paint remaining on the downstream side of the discharge channel switching valve 48, that is, the coating line 60 including the supply channel 45, the pump unit 47, and the coating machine 3. .

  As a result, the paint remaining in the first and second discharge channels 29 and 32 can be recovered by being pushed back into the first and second tanks 6 and 18 by the pressurized air from the pressurized air source 25. As a result, the amount of paint to be discarded can be reduced. Further, since the cleaning range is only the supply channel 45, the pump unit 47, and the coating machine 3, the amount of cleaning liquid used can be reduced, and the cleaning time can be shortened. Thereby, improvement of painting efficiency, reduction of painting cost, etc. can be aimed at.

  Further, the amount of paint stored in each tank 6, 18 is set to a small amount, for example, about 200 to 1000 cc, for example, one electrostatic coating apparatus 1 uses in one painting operation. Thereby, since the whole can be formed small and light, it can be installed freely and the degree of design freedom can be improved. In addition, since the tanks 6 and 18 store a small amount of paint, the charging capacity is small, and the safety against electric shock or the like can be improved.

  The recovery valve 51 includes a first recovery air supply valve 51 </ b> B provided between the pressurized air source 25 and the first discharge passage 29, and a pressurized air source 25 and the second discharge passage 32. And a second recovered air supply valve 51C. Accordingly, by opening the first recovery air supply valve 51B or the second recovery air supply valve 51C, the first discharge flow path 29 or the second discharge flow is supplied by the pressurized air from the pressurized air source 25. The paint remaining in the path 32 can be collected.

  On the other hand, the filling channels 21 and 22 are provided with filling valves 35 and 38 for filling the tanks 6 and 18 with paint and exhaust valves 36 and 39 for discharging the air in the tanks 6 and 18, respectively. Yes. Thereby, the tanks 6 and 18 can be filled with the paint from the paint source 19 only by opening the filling valves 35 and 38. When filling the paint, the exhaust valves 36 and 39 are opened, so that the air corresponding to the paint filling amount can be discharged from the tanks 6 and 18 and the internal pressure rise can be suppressed. Filling operation can be performed smoothly.

  In addition, paint extruding valves 37 and 40 for supplying pressurized air from the pressurized air source 25 connected to the first and second tanks 6 and 18 are provided. Accordingly, when painting, by supplying the pressurized air from the pressurized air source 25 into the tanks 6 and 18 by the paint extrusion valves 37 and 40, the paint in the tanks 6 and 18 is pushed by the pressurized air. Can be put out. Thereby, a coating material can be positively supplied to the supply flow path 45 and the coating machine 3 side.

  Further, the first and second tanks 6 and 18 made of an insulating material are defined by an upper high-voltage cutoff chamber 9 and a lower paint storage chamber 10 by a two-chamber defining plate 8, and on the upper side. Is provided with a paint inlet 11 through which the paint flows into the paint storage chamber 10 and a paint outlet 16 through which the paint in the paint storage chamber 10 flows out at the lower side.

  Accordingly, since the paint filled in the paint storage chamber 10 can be insulated from the paint source 19 by the high voltage shut-off chamber 9, the high voltage applied to the paint passes through the filling channels 21 and 22 and the paint source 19. Therefore, it is possible to prevent leakage to the ground potential, and good electrostatic coating can be performed. In addition, the two-compartment defining plate 8 provided in each of the tanks 6 and 18 can prevent the paint in the paint storage chamber 10 from flowing into the high-voltage shut-off chamber 9. Insulation performance can be maintained.

  Further, regarding the system on the first tank 6 side, a recovery flow path 30 that branches off from the middle of the discharge flow path 29 and communicates with the paint storage chamber 10 of the tank 6 is provided. A tank outflow valve 41 is provided between the branch position 31 of the flow path 30 and the tank 6, and a tank recovery valve 42 is provided in the recovery flow path 30.

  As a result, when coating the paint stored in the paint storage chamber 10 of the first tank 6, the paint is supplied to the coating machine 3 through the discharge flow path 29 by opening the tank outflow valve 41. can do. Further, when the tank recovery valve 42 is opened, the paint remaining in the discharge passage 29 can be recovered in the tank 6 and the amount of paint discarded can be reduced. Furthermore, since the first tank 6 can be electrically separated from the coating machine 3 side, the next coating can be filled with the tank 6 connected to the ground potential, spark discharge, etc. It is possible to perform the filling operation of the paint in a state where the above is prevented.

  On the other hand, as for the system on the second tank 18 side, when the tank recovery valve 44 is opened, the remaining paint can be recovered in the tank 18 as described above. Further, the second tank 18 can be electrically separated from the coating machine 3 side, and can be filled with the paint for the next time while being connected to the ground potential.

  Next, FIG. 7 shows a second embodiment of the present invention. The feature of this embodiment is that it is configured to apply a two-component paint comprising a main agent and a curing agent by an electrostatic coating apparatus. In the second embodiment, the main parts of the electrostatic coating apparatus according to the first embodiment described above are the same, and therefore the same components are denoted by the same reference numerals and the description thereof is omitted. And

  In FIG. 7, reference numeral 61 denotes an electrostatic coating apparatus according to the second embodiment. The electrostatic coating apparatus 61 is for applying a so-called two-component paint using a main component containing a pigment and a curing agent as a curing catalyst for curing the main component in a predetermined ratio. Therefore, the electrostatic coating apparatus 61 according to the second embodiment uses the configuration of the portion corresponding to the electrostatic coating apparatus 1 according to the first embodiment described above as the main agent supply apparatus 62. What is this main agent supply apparatus? It is set as the structure which provides the hardening | curing agent supply apparatus 64 separately.

  62 is a main agent supply device for supplying the main agent of the two-component paint, except that the main agent supply device 62 is connected to the main agent source 63 in place of the paint source 19 according to the first embodiment described above. The configuration is the same as that of the electrostatic coating apparatus 1 according to the first embodiment. As the main agent, a conductive paint can be used as in the first embodiment.

  Next, reference numeral 64 denotes a curing agent supply device of the electrostatic coating device 61. The curing agent supply device 64 supplies a curing agent as a curing catalyst for curing the main agent to the coating machine 3 at a predetermined ratio corresponding to the flow rate of the main agent. The curing agent supply device 64 includes a curing agent source 65, a curing agent control valve 66, a curing agent supply channel 67, a cleaning fluid switching valve 68, a cleaning fluid channel 69, a curing fluid line 70, a pump unit 72, which will be described later. This is roughly constituted by a selective supply valve 73 and the like.

  A curing agent source 65 supplies a curing agent to the curing agent supply device 64. Reference numeral 66 denotes a curing agent control valve (denoted as “CV3” in FIG. 7) that adjusts the supply pressure of the curing agent fed by pressure from the curing agent source 65.

  Reference numeral 67 denotes a curing agent supply channel for supplying the curing agent toward the coating machine 3. One end of the curing agent supply channel 67 is connected to a curing agent source 65 via a curing agent control valve 66. On the other hand, the other end of the curing agent supply channel 67 is connected to a curing agent valve 73A of a selective supply valve 73 described later.

  Reference numeral 68 denotes a cleaning fluid switching valve that selectively supplies pressurized air (cleaning air) and cleaning liquid. The cleaning fluid switching valve 68 is substantially the same as the cleaning fluid switching valve 52 according to the first embodiment, and includes a cleaning air supply valve 68A connected to the pressurized air source 25 via the third pressure regulator 53, The cleaning liquid supply valve 68B is connected to the cleaning liquid source 55 via the cleaning liquid control valve 54.

  Reference numeral 69 denotes a cleaning fluid flow path having one end connected to the cleaning fluid switching valve 68. The other end of the cleaning fluid channel 69 is connected to a cleaning valve 73B of a selective supply valve 73 described later.

  Reference numeral 70 denotes a curing agent line having one end connected to a joining position 71 between the curing agent supply channel 67 and the cleaning fluid channel 69. The other end of the curing agent line 70 joins the supply flow path 45 on the main agent supply device 62 side via a pump unit 72 including a gear pump 72A and a trigger valve 72B.

  Reference numeral 73 denotes a selective supply valve provided in connection with the curing agent supply flow path 67. The selective supply valve 73 selects the curing agent from the curing agent source 65, the pressurized air and the cleaning liquid from the cleaning fluid switching valve 68, and supplies them to the coating machine 3. The selective supply valve 73 includes a curing agent valve 73A provided in the curing agent supply channel 67 and a cleaning valve 73B provided in the cleaning fluid channel 69.

  Thus, also in the second embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment described above. In particular, according to the second embodiment, the selective supply valve 73 can mix the curing agent from the curing agent supply device 64 with the main agent from the main agent supply device 62, and the two-component paint from the coating machine 3. Can be painted. Further, the selective supply valve 73 can wash the two-component paint remaining after the completion of painting by supplying pressurized air and washing liquid for washing to the coating machine 3.

  Next, FIG. 8 and FIG. 9 show a third embodiment of the present invention. A feature of the present embodiment is that a filling nozzle and a paint receiving projection are provided facing each other in the upward and downward directions in the tank. Note that in the third embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted. In the third embodiment, the first tank will be described. Since the second tank has the same shape as the first tank, the description thereof will be omitted.

  In FIG. 8, reference numeral 81 denotes a first tank according to the third embodiment. A filling nozzle 82 is located in the container body 7 and connected to the paint inlet 11. The filling nozzle 82 is formed in a substantially conical shape with a pointed lower end portion, and an upper portion thereof is attached to the lower surface side of the lid portion 7B. In addition, a plurality of paint passages 82 </ b> A through which the paint from the paint inflow port 11 circulates along a substantially conical outer surface is provided at the top of the filling nozzle 82.

  Then, when the paint flowing into the container body 7 is continuously supplied to the paint storage chamber 10 by dropping, the filling nozzle 82 concentrates the paint at one point of the substantially conical tip, and the paint is described later. It is dropped toward the upper end of the receiving projection 83.

  Reference numeral 83 denotes a paint receiving projection provided on the bottom 7 </ b> C of the container body 7. The paint receiving projection 83 has, for example, a conical shape protruding upward from the paint filled in the paint containing chamber 10. Further, the paint receiving projection 83 is arranged so that the sharp upper end portion is directly below the tip of the filling nozzle 82. On the other hand, as shown in FIGS. 8 and 9, the lower portion of the paint receiving projection 83 is attached to the bottom 7C via a plurality of legs 83A in order to secure a space for the paint to circulate.

  Then, the paint receiving projection 83 receives the paint dropped and supplied from the filling nozzle 82 at the upper end portion and causes the paint to flow along the conical outer surface. Thus, the paint receiving projection 83 can prevent the falling paint from directly colliding with the liquid surface of the paint storage chamber 10 and prevent air bubbles from being involved in the paint.

  Thus, also in the third embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment described above. In particular, according to the third embodiment, the coating material is dropped and supplied from the filling nozzle 82 to the coating material receiving projection 83, thereby preventing the entrainment of bubbles in the coating material and improving the coating quality.

  Next, FIG. 10 shows a fourth embodiment of the present invention. The feature of this embodiment is that the filling nozzle is extended to the paint chamber. Note that in the fourth embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted. In the fourth embodiment, the first tank will be described, and the second tank has the same shape as the first tank, so that the description thereof will be omitted.

  In FIG. 10, reference numeral 91 denotes a first tank according to the fourth embodiment. A filling nozzle 92 is located in the container body 7 and connected to the paint inlet 11. The filling nozzle 92 has a tube shape extending in the upward and downward directions, and is attached to the lower surface side of the lid portion 7B so that the upper portion thereof communicates with the paint inlet 11. Further, the lower portion of the filling nozzle 92 extends to the bottom side of the paint chamber 10 (near the paint outlet 16). Thereby, the filling nozzle 92 can prevent the coating material from colliding with the liquid level of the coating material storage chamber 10, and can prevent air bubbles from being caught in the coating material.

  In addition, a slit 92A is formed below the filling nozzle 92, and the slit 92A extends to a position higher than the liquid level of the paint storage chamber 10, for example, to the vicinity of the two-chamber defining plate 8. The slit 92 </ b> A is for allowing the entire amount of the paint in the filling nozzle 92 to flow out when the supply of the paint to the paint storage chamber 10 is stopped. Furthermore, the filling nozzle 92 is formed using a material having high electrical insulation and high water repellency (high surface tension), such as polytetrafluoroethylene (PTFE). Thereby, when the supply of the paint to the paint storage chamber 10 is stopped, the paint attached to the inner surface of the filling nozzle 92 can be separated by the surface tension, and the high voltage is prevented from leaking through the attached paint. be able to.

  Thus, also in the fourth embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment described above. In particular, according to the fourth embodiment, it is possible to prevent entrainment of bubbles in the coating material by the filling nozzle 92 extending to the coating material storage chamber 10 and improve the coating quality.

  Next, FIG. 11 shows a fifth embodiment of the present invention. The feature of the present embodiment is that the filling nozzle is extended to the paint chamber and is formed in a spiral shape to extend the insulation distance. Note that in the fifth embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted. In the fifth embodiment, the first tank will be described, and the second tank has the same shape as the first tank, so that the description thereof will be omitted.

  In FIG. 11, reference numeral 101 denotes a first tank according to the fifth embodiment. Reference numeral 102 denotes a filling nozzle located in the container body 7 and connected to the paint inlet 11. The filling nozzle 102 has a tube shape extending upward and downward, and is attached to the lower surface side of the lid portion 7 </ b> B so that the upper portion thereof communicates with the paint inlet 11. Further, the lower portion of the filling nozzle 102 extends to the bottom side of the paint containing chamber 10 (near the paint outlet 16). Further, a slit 102A is formed on the lower side of the filling nozzle 102, and the slit 102A extends, for example, to the vicinity of the two-compartment defining plate 8.

  On the other hand, the upper side of the filling nozzle 102 is a spiral portion 102 </ b> B in the high voltage cutoff chamber 9. The spiral portion 102B is configured to increase the insulating distance between the inner surface and the outer surface of the filling nozzle 102 by forming the passage length of the filling nozzle 102 in the high voltage cutoff chamber 9 to be long. Furthermore, the filling nozzle 102 is formed by using a material having high electrical insulation and high water repellency (high surface tension), like the filling nozzle 92 according to the fourth embodiment.

  Thus, also in the fifth embodiment configured as described above, it is possible to obtain substantially the same function and effect as those of the first embodiment described above. In particular, according to the fifth embodiment, in addition to the effects of the fourth embodiment described above, the spiral portion 102B of the filling nozzle 102 can reliably prevent high voltage leakage with high electrical insulation. Can do.

  Next, FIG. 12 shows a sixth embodiment of the present invention. The feature of this embodiment is that the cylindrical portion of the container body is provided with an uneven inner surface for extending the creepage distance, the lower side of the filling nozzle is extended to the paint containing chamber, and the upper side is formed in a spiral shape. is there. Note that in the sixth embodiment, the same components as those in the first embodiment described above are denoted by the same reference numerals, and description thereof is omitted. In the sixth embodiment, the first tank will be described, and the second tank has the same shape as the first tank, so that the description thereof will be omitted.

  In FIG. 12, reference numeral 111 denotes a first tank according to the sixth embodiment. Reference numeral 112 denotes a container body that forms the outer shape of the first tank 111. Here, the container main body 112 is formed of a cylindrical portion 112A, a lid portion 112B, and a bottom portion 112C. Further, the inner peripheral side of the cylindrical portion 112A is an uneven inner surface 113 located on the high voltage cutoff chamber 9 side. The uneven inner surface 113 alternately arranges the reduced diameter portion and the enlarged diameter portion, thereby extending the creeping distance of the inner surface of the high voltage cutoff chamber 9 and increasing the electrical insulation distance.

  Reference numeral 114 denotes a filling nozzle located in the container body 112 and connected to the paint inlet 11. The filling nozzle 114 has a tube shape extending upward and downward, and is attached to the lower surface side of the lid portion 112 </ b> B so that the upper portion thereof communicates with the paint inlet 11. Further, the filling nozzle 114 extends to the bottom side of the coating material storage chamber 10, and a slit 114A is formed on the lower side thereof.

  On the other hand, the upper side of the filling nozzle 114 is a spiral portion 114 </ b> B in the high voltage cutoff chamber 9. The spiral portion 114B increases the insulation distance between the inner surface and the outer surface of the filling nozzle 114 by forming the passage length of the filling nozzle 114 in the high voltage cutoff chamber 9 to be long. Further, the filling nozzle 114 is formed by using a material having high electrical insulation and high water repellency (high surface tension), like the filling nozzle 92 according to the fourth embodiment.

  Thus, in the sixth embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment described above. In particular, according to the sixth embodiment, in addition to the operational effects of the fifth embodiment described above, the cylindrical portion 112A of the container body 112 is provided with an uneven inner surface 113 for extending the creepage distance. Therefore, the insulation performance of the container body 112 can be improved.

  In the first embodiment, the first air flow path 49B of the recovery air flow path 49 passes through the first valve body 48A of the first recovery air supply valve 51B and the discharge flow path switching valve 48 to the first. The second air passage 49C is connected to the second discharge passage 32 through the second recovery air supply valve 51C and the second valve body 48B of the discharge passage switching valve 48. The case has been described as an example. However, the present invention is not limited to this. For example, the first and second air flow paths 49B and 49C of the recovery air flow path 49 are not passed through the valve bodies 48A and 48B of the discharge flow path switching valve 48. The recovery air supply valves 51B and 51C may be connected directly to the discharge passages 29 and 32. This configuration can be similarly applied to other embodiments.

  Moreover, although the normally closed switch having the normally closed contact is illustrated as the earth switches 58 and 59, a normally open switch may be used. Of course, a non-contact switch such as a semiconductor switch, an electronic switch, or an optical switch may be used.

  Furthermore, in each embodiment, the coating machine 3 provided with the rotary atomizing head 3B as a spraying means was described as an example. However, the present invention is not limited to this. For example, a coating machine provided with an air atomizing nozzle, a hydraulic atomizing nozzle, or the like may be used as the spraying means.

1 is an external view showing an electrostatic coating apparatus according to a first embodiment of the present invention. It is a whole lineblock diagram showing the electrostatic painting device by a 1st embodiment of the present invention. It is a circuit block diagram which shows the electrostatic coating apparatus of FIG. 2 with a concrete circuit. It is a longitudinal cross-sectional view which expands and shows a 1st tank. It is the cross-sectional view which looked at the 1st tank from the arrow VV direction in FIG. It is a time chart which shows operation | movement of the electrostatic coating apparatus by 1st Embodiment. It is a circuit block diagram which shows the electrostatic coating apparatus by the 2nd Embodiment of this invention. It is a longitudinal cross-sectional view which shows the 1st tank by the 3rd Embodiment of this invention. It is the cross-sectional view which looked at the 1st tank from the arrow IX-IX direction in FIG. It is a longitudinal cross-sectional view which shows the 1st tank by the 4th Embodiment of this invention. It is a longitudinal cross-sectional view which shows the 1st tank by the 5th Embodiment of this invention. It is a longitudinal cross-sectional view which shows the 1st tank by the 6th Embodiment of this invention.

Explanation of symbols

1,61 Electrostatic coating equipment 2 Coating robot 3 Coating machine (spraying means)
5 High-voltage generator 6, 81, 91, 101, 111 First tank 7, 112 Container body 8 Two-chamber defining plate 9 High-voltage block chamber 10 Paint storage chamber 14, 82, 92, 102, 114 Filling nozzle 17 Collected paint passage 18 Second tank 19 Paint source 21 First filling flow path 22 Second filling flow path 23 First air discharge flow path 24 Second air discharge flow path 25 Pressurized air source 27 First Extrusion air flow path 28 Second extrusion air flow path 29 First discharge flow path 30 First recovery flow path 31, 34 Branch position 32 Second discharge flow path 33 Second recovery flow path 35 First filling Valve 36 First exhaust valve 37 First paint push-out valve 38 Second fill valve 39 Second exhaust valve 40 Second paint push-out valve 41 First tank outflow valve 42 First tank recovery valve 43 Second Tank outflow valve 44 Second tank recovery 45 Supply flow path 46, 71 Merge position 47, 72 Pump unit 48 Discharge flow path switching valve 51 Recovery valve 55 Cleaning liquid source 57 Cleaning valve 58 First earth switch 59 Second earth switch 60 Paint line 62 Main agent supply apparatus 63 Main agent source 64 Hardener supply device 65 Hardener source 67 Hardener supply flow path 70 Hardener line 73 Selective supply valve

Claims (7)

Spray means for applying a high voltage to the supplied paint and spraying it toward the object to be coated;
First and second tanks comprising two independent containers for storing paint;
First and second filling passages for filling the first and second tanks with paint from a paint source;
First and second discharge flow paths for discharging the paint stored in the first and second tanks;
A supply flow path having one end joined to and connected to the first and second discharge flow paths and the other end connected to the spraying means;
A discharge flow path switching valve that is provided connected to the first and second discharge flow paths and the supply flow path, and connects the first and second discharge flow paths to the supply flow path; and
Connected to the first and second discharge flow paths, and after the discharge flow path switching valve switches from one discharge flow path to the other discharge flow path, the remaining paint in the one discharge flow path is removed. A recovery valve for supplying pressurized air from a pressurized air source to the one discharge flow path in order to recover to one tank;
Washing with pressurized air from a pressurized air source provided to be connected to the supply flow path and for cleaning the paint remaining in the supply flow path and the spraying means after completion of the painting operation by the spraying means A cleaning valve for supplying cleaning liquid from a liquid source;
An electrostatic switch provided in each of the first and second tanks and configured to include an earth switch that opens the one tank, which supplies paint to the spraying means for painting work, with respect to the ground. Painting equipment.   The recovery valve includes a first recovery air supply valve provided between the pressurized air source and the first discharge flow path, and between the pressurized air source and the second discharge flow path. The electrostatic coating apparatus of Claim 1 provided with the 2nd collection | recovery air supply valve provided.   The first and second filling flow paths include a filling valve that fills the one tank with paint after being switched from the one discharge flow path to the other discharge flow path by the discharge flow path switching valve. The electrostatic coating apparatus according to claim 1, wherein an exhaust valve for discharging air in the tank when the tank is filled with paint by the filling valve is provided.   2. A paint extrusion valve for supplying pressurized air from a pressurized air source into the first and second tanks to extrude the paint filled in the first and second tanks. 2. The electrostatic coating apparatus according to 2 or 3. The first and second tanks are formed as containers using an insulating material,
The container is defined by an upper high voltage cut-off chamber and a lower paint storage chamber by a two-chamber defining plate having a paint circulation hole,
A paint inlet is provided on the upper side of the container to allow the paint to flow into the paint storage chamber from the high voltage shut-off chamber through the paint circulation hole of the two-chamber defining plate,
5. The electrostatic coating apparatus according to claim 1, 2, 3, or 4, wherein a paint outflow port through which the paint in the paint containing chamber flows out is provided on a lower side of the container. One end is branched from the middle of the discharge flow path, and the other end is provided with a recovery flow path communicating with the paint storage chamber of the tank,
The discharge flow path is provided with a tank outflow valve that is located between the branch position of the recovery flow path and the tank and opens when supplying paint toward the spraying means,
The electrostatic coating apparatus according to claim 5, wherein the recovery flow path is provided with a tank recovery valve that opens when recovering the paint toward the tank. Spray means for applying a high voltage to the supplied paint and spraying it toward the object to be coated;
First and second tanks comprising two independent containers for storing the main component of the two-component paint;
First and second filling flow paths for filling the first and second tanks with the main agent from the main agent source;
First and second discharge flow paths for discharging the main agent stored in the first and second tanks;
A main agent supply flow path having one end joined to and connected to the first and second discharge flow paths and the other end connected to the spraying means;
A discharge flow path switching valve that is connected to the first and second discharge flow paths and the main agent supply flow path, and connects the first and second discharge flow paths to the main agent supply flow path; and
The remaining main agent in the one discharge flow path is provided after being connected to the first and second discharge flow paths and switched from one discharge flow path to the other discharge flow path by the discharge flow path switching valve. A recovery valve for supplying pressurized air from a pressurized air source to the one discharge flow path in order to recover to one tank;
Pressurized air from a pressurized air source is connected to the main agent supply flow path and is used to wash the main agent remaining in the main agent supply flow path and the spray means after the completion of the painting operation by the spray means. And a main agent side cleaning valve for supplying cleaning liquid from the cleaning liquid source,
An earth switch that is provided in each of the first and second tanks and that opens the one tank that supplies the main agent toward the spraying means for painting work with respect to the earth;
A curing agent supply flow path having one end connected to the curing agent source of the two-component paint and the other end joined to the supply flow path;
A static supply valve that is provided in the curing agent supply flow path and includes a selective supply valve that selects and supplies a curing agent from a curing agent source, pressurized air for cleaning, and cleaning liquid to the spraying means. Painting equipment.

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