Additional component applicable to electrostatic coating apparatus and electrostatic coating apparatus

Abstract

To provide an electrostatic coating apparatus which improves electric field strength in the neighborhood of electrode, in a matter loaded with an angle-muzzle and a long-muzzle at the tip of a coating gun.SOLUTION: Additional component applicable to an electrostatic coating apparatus is applied to the electrostatic coating apparatus which has a coating gun and a muzzle to be attached to a tip of the coating gun and has an attachment component and a conductor. The attachment component has a holding part which is formed cylindrically, and holds a muzzle so that the muzzle is inserted thereto, a support part which supports the coating gun and a connection part which connects the holding part and the support part, and the holding part, the support part and the connection part are formed into seamless one body by using an electric insulation member, and is fitted to the coating gun and the muzzle. The conductor is constituted with a member having conductivity, in such a case that mounted components are mounted onto the coating gun and the muzzle, the tip side is exposed to the tip side of the muzzle, the base end side is connected with a ground and, at the same time, a wiring path from the tip side to the base end side is caused to pass through an inner part of the mounted components.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] An embodiment of the present invention relates to an add-on part applicable to an electrostatic coating device, and to an electrostatic coating device. [Background technology]

[0002] Conventionally, electrostatic coating devices have sometimes improved workability by attaching a so-called angle muzzle to the tip of the coating gun to change the paint spray angle or a so-called long muzzle to extend the paint spray position, for example, when coating a deep object or the bottom surface of a box.

[0003] In order to increase the electric field strength in the vicinity of the electrode in an electrostatic coating device, a technique has been developed in which a conductor connected to ground is provided. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-166073 Summary of the Invention [Problem to be solved by the invention]

[0005] However, with the conventional configuration, it was difficult to apply a conductor when an angled muzzle or a long muzzle was attached to the tip of the spray gun.

[0006] The present invention has been made in consideration of the above-mentioned circumstances, and its object is to provide an add-on part applicable to an electrostatic coating device that can increase the electric field strength near the electrode when an angle muzzle or long muzzle is attached to the tip of the coating gun, and an electrostatic coating device to which this add-on part is applied. [Means for solving the problem]

[0007] An add-on component applicable to an electrostatic coating apparatus according to an embodiment is applicable to an electrostatic coating apparatus having a paint gun and a muzzle attached to the tip of the paint gun. The add-on component includes an attachment component and a conductor. The attachment component includes a cylindrical holding portion into which the muzzle is inserted and which holds the muzzle, a support portion which supports the paint gun, and a connection portion which connects the holding portion and the support portion. The holding portion, the support portion, and the connection portion are seamlessly formed as a single unit using an electrically insulating material, and the conductor is attached to the paint gun and the muzzle. The conductor is made of a conductive material, and when the attachment component is attached to the paint gun and the muzzle, the tip side is exposed at the tip side of the muzzle and the base side is connected to ground, and a wiring path from the tip side to the base side is routed through the attachment component.

[0008] The electrostatic coating device also includes the coating gun, the muzzle, and the additional part. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram conceptually illustrating an example of an electrostatic coating device according to an embodiment. [Figure 2] FIG. 10 is a diagram showing an example in which an add-on part for an angle muzzle according to an embodiment is attached to a paint gun and an angle muzzle. [Figure 3] 1 is a perspective view of an example of an additional part that can be attached to an angle muzzle, as viewed from above, for an additional part for an angle muzzle according to an embodiment; [Figure 4] 1 is a perspective view of an add-on part for an angle muzzle according to one embodiment, the add-on part being attachable to the angle muzzle, as seen from below; [Figure 5] FIG. 1 is a cross-sectional view showing the internal structure of an example in which an additional part for an angle muzzle according to an embodiment is attached to a paint gun and an angle muzzle. [Figure 6] 6 is an enlarged cross-sectional view taken along line X6-X6 in FIG. 5 showing an example in which an additional part for an angle muzzle according to one embodiment is attached to a paint gun and an angle muzzle. [Figure 7]10A and 10B are diagrams illustrating an example of attaching and detaching an add-on part for an angle muzzle to and from a paint gun and an angle muzzle according to an embodiment. [Figure 8] FIG. 10 is a diagram showing an example in which an add-on part for a long muzzle according to one embodiment is attached to a paint gun and a long muzzle. [Figure 9] 10A and 10B are diagrams illustrating an example of attaching and detaching an add-on part for a long muzzle to and from a paint gun and a long muzzle according to an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] An embodiment will be described below with reference to the drawings. First, the overall configuration of an electrostatic coating device using the additional part of this embodiment will be described with reference to Fig. 1. The electrostatic coating device 1 of this embodiment includes a coating gun 10, a controller 20, a muzzle 30, and an additional part 2.

[0011] The paint gun 10 is an electrostatic spray gun that can spray, for example, powder paint by electrostatic coating, thereby applying the paint to the workpiece 100. The paint gun 10 can be configured as a so-called automatic gun that is attached to the tip of an actuator such as a reciprocator or a robot arm, for automatically painting the workpiece. The paint gun 10 can also be configured as a so-called manual gun that is held by an operator.

[0012] The paint gun 10 includes a supply path 11, a nozzle 12, an electrode 13, and a high-voltage generator 14, and is connected to a paint supply device 80. The paint supply device 80 includes, for example, a paint tank 81, a screw feeder 82, an air supply source 83, an air supply valve 84, and an injector 85, and supplies paint stored in the paint tank 81 to the paint gun 10.

[0013] Screw feeder 82 supplies a fixed amount of paint at a set discharge rate. Air supply source 83 is composed of a compressor or the like, and supplies compressed air to injector 85 in response to the opening and closing of air supply valve 84. Injector 85 receives compressed air from air supply source 83, uses the Venturi effect to suck in paint discharged from screw feeder 21, and supplies the paint to paint gun 10.

[0014] The nozzle 12 is used to eject paint in a predetermined pattern onto the workpiece 100, and is provided at the tip of the electrostatic coating device 1. The electrode 13 is used to charge the paint ejected from the nozzle 12 to a high voltage.

[0015] The paint gun 10 is connected to the controller 20 via a cable. The controller 20 supplies an AC voltage to the paint gun 10. The high voltage generator 14 outputs a DC high voltage proportional to the AC voltage input from the controller 20. In this embodiment, the high voltage generator 14 boosts the externally input voltage by approximately 5000 to 6000 times and outputs the boosted voltage.

[0016] The high voltage generator 14 has an input transformer 141, a boost circuit 142, and an output resistor 143. The input side, i.e., the primary side, of the input transformer 141 is connected to the electrostatic controller 20. On the other hand, the output side, i.e., the secondary side, of the input transformer 141 is connected to the input side of the boost circuit 142 by, for example, a metal wire. In this way, the input transformer 141 electrically insulates the electrostatic controller 20 from the boost circuit 142, and outputs the AC voltage Vac supplied from the electrostatic controller 20 to the input side of the boost circuit 142.

[0017] The boost circuit 142 is configured by, for example, a Cockcroft-Walton type boost rectifier circuit. The boost circuit 142 boosts and rectifies the AC voltage Vac input from the input transformer 141 to convert it into a high DC voltage. The output side of the boost circuit 142 is connected to an output resistor 143 by, for example, a metal wire.

[0018] The output resistor 143 is, for example, a plate-shaped resistor, and is provided between the boost circuit 142 and the electrode 13. The high DC voltage output from the boost circuit 142 is supplied to the electrode 13 via the output resistor 143, and is output from the electrode 13 as a DC output voltage Vdc. The electrode 13 is, for example, a pin-shaped metal electrode, and is provided near the nozzle 12. As a result, the DC output voltage Vdc output from the electrode 13 is applied to the paint particles ejected from the nozzle 12.

[0019] In this embodiment, the electrostatic controller 20 supplies an AC voltage of, for example, 12 V to 20 V to the primary side of the input transformer 141 of the paint gun 10. The input transformer 141 converts the AC voltage supplied from the electrostatic controller 20 to an AC voltage of approximately 2 kV to 4 kV on the secondary side and outputs it to the boost circuit 142. The boost circuit 142 boosts the AC voltage supplied from the input transformer 141 to a high DC voltage of 60 kV to 100 kV and supplies it to the electrode 13. The electrode 13 then outputs the high voltage supplied from the high voltage generator 14 to the vicinity of the nozzle 12, charging the paint ejected from the nozzle 12 to a high voltage. In this way, electrostatic painting is performed on the workpiece 100.

[0020] The muzzle 30 is detachably attached to the tip of the paint gun 10 and covers the nozzle 12 and the electrode 13. The muzzle 30 may be, for example, a so-called angle muzzle for changing the paint ejection angle, or a so-called long muzzle for extending the paint ejection position. The paint ejected from the nozzle 12 passes through the muzzle 30 and is ejected from the tip of the muzzle 30.

[0021] The additional part 2 is applicable to the paint gun 10, and as shown in FIG. 2, is detachably attached to the paint gun 10 to which the muzzle 30 is attached. Note that FIGS. 2 to 7 show an example of an angle muzzle as the muzzle 30. The additional part 2 has the function of increasing the electric field strength near the electrode 13. As shown in FIGS. 3 to 6, the additional part 2 includes an attachment part 40, a conductor 50, and a resistor 60. In the following description, the side of the paint gun 10 facing the muzzle 30 is referred to as the front side, and the side opposite the muzzle 30 is referred to as the rear side. The direction horizontal to and perpendicular to the front-to-rear direction of the paint gun 10 is referred to as the width direction of the paint gun 10 and the additional part 2.

[0022] The attachment part 40 is made of an electrically insulating and flexible material that can be bent or curved, such as silicone resin or rubber, and includes a holding part 41, a support part 42, and a connecting part 43. The attachment part 40 has stretchability or elasticity that allows it to expand and contract. The holding part 41, the support part 42, and the connecting part 43 are molded seamlessly as a single piece.

[0023] The holding portion 41 constitutes the tip side of the attachment 40. As shown in FIG. 3 etc., the holding portion 41 is cylindrical and configured so that the muzzle 30 can be inserted inside. The holding portion 41 holds the muzzle 30 when the muzzle 30 is inserted inside. The inner diameter of the holding portion 41 can be set to a dimension slightly smaller than the outer diameter of the muzzle 30, for example. When the muzzle 30 is inserted into the holding portion 41, the holding portion 41 can firmly hold the muzzle 30 by tightening the muzzle 30 using its stretchability or elasticity.

[0024] The support portion 42 functions to support the paint gun 10. As shown in FIG. 3 , the support portion 42 can be configured to include a flat plate portion 421, sidewall portions 422, and a threaded hole 423. The flat plate portion 421 is configured as a flat plate and contacts the bottom surface of the paint gun 10 to support the paint gun 10. The sidewall portions 422 are configured as plates extending from both sides of the flat plate portion 421 and contact the side surfaces of the paint gun 10. The sidewall portions 422 function to restrict movement of the support portion 42 in the width direction relative to the paint gun 10. The threaded hole 423 is formed through the flat plate portion 421 in the thickness direction. A screw 90 is inserted into the threaded hole 423 from the outside of the flat plate portion 421, i.e., from the side opposite the paint gun 10. The screw 90 is threaded into a female threaded hole provided in the paint gun 10. As a result, the support portion 42 is fixed to the bottom surface of the paint gun 10 by the screw 90.

[0025] The connecting portion 43 is formed into a long plate shape overall, and connects the holding portion 41 and the support portion 42. That is, the holding portion 41 is provided at the tip end of the connecting portion 43, and the support portion 42 is provided at the base end portion of the connecting portion 43. Furthermore, when the object to which the additional part 2 is attached is an angle muzzle, the axial direction of the cylindrical central axis of the holding portion 41 is inclined with respect to the longitudinal direction of the connecting portion 43 according to the angle of the angle muzzle.

[0026] The conductor 50 is made of a conductive material. When the attachment 40 is attached to the paint gun 10 and the muzzle 30, the tip side of the conductor 50 is exposed at the tip side of the muzzle 30, and the base side is connected to ground. Most of the conductor 50, specifically, the wiring path from the base end side to the tip side of the conductor 50, passes through the inside of the attachment 40.

[0027] In this embodiment, the conductor 50 has an exposed portion 51, a contact portion 52, and a wiring portion 53, as shown in Figures 5 and 6. The exposed portion 51, the contact portion 52, and the wiring portion 53 may be seamlessly molded from the same conductive material, such as copper or aluminum, or may be formed by joining different conductive members together by welding or the like. The exposed portion 51 forms the tip of the conductor 50. The exposed portion 51 is needle-shaped and protrudes forward from the tip of the attachment part 40, exposed to the outside of the attachment part 40. In this case, the exposed portion 51 preferably has a rigidity sufficient to prevent it from breaking or being bent even when an external force is applied to the exposed portion 51, for example.

[0028] The contact portion 52 constitutes the base end of the conductor 50. The contact portion 52 is formed, for example, in a stepped cylindrical shape, and is provided on the support portion 42 of the mounting component 40 in a state exposed to the outside, as shown in FIG. 6. In the present embodiment, as shown in FIGS. 3 and 6, the support portion 42 has an exposure hole 424. The exposure hole 424 is formed in a shape that is dug from the upper surface side of the support portion 42 to halfway in the thickness direction of the support portion 42. The contact portion 52 is embedded in the mounting component 40 with its upper surface exposed from the exposure hole 424.

[0029] Resistor 60 is provided in wiring portion 53 and is embedded inside mounting component 40 in the same manner as wiring portion 53. The resistance value of resistor 60 is set appropriately depending on, for example, the electrical characteristics of the paint and object 100 to be coated, the voltage value applied to electrode 13, etc.

[0030] The conductor 50 and resistor 60 function to reduce the output current from the electrode 13, thereby suppressing a voltage drop at the electrode 13 and thereby maintaining an appropriate electric field strength from the electrode 13 to the workpiece 100. Increasing the electric field strength from the electrode 13 to the workpiece 100 applies a strong electrostatic force to the paint particles ejected from the paint gun 10, allowing the paint particles to move toward the workpiece 100 more quickly and accurately. This improves the adhesion efficiency to the workpiece 100 and reduces the amount of paint particles that fly off, thereby preventing paint waste and pollution of the work environment. Furthermore, by maintaining an appropriate output current from the electrode 13 using the conductor 50, the back ionization phenomenon, in which charged paint particles are repelled by ions of the same polarity, can be suppressed, resulting in improved paint texture and paint quality.

[0031] In this embodiment, the paint gun 10 further includes an elastic member 18. The elastic member 18 is configured from a conductive metal spring or the like, and is connected to ground, for example, through the interior of the paint gun 10. When the attachment part 40 is attached to the paint gun 10 and the muzzle 30, the elastic member 18 elastically contacts the contact portion 52 exposed from the exposure hole 424. As a result, the conductor 50 is connected to ground through the paint gun 10.

[0032] The wiring portion 53 is a portion that electrically connects the exposed portion 51 and the contact portion 52, and serves as a wiring path from the exposed portion 51, which is the tip side of the conductor 50, to the contact portion 52, which is the base end side. In this case, at least the wiring portion 53 of the conductor 50, which serves as the wiring path, is made of a material that can be bent along the bending of the attachment component 40, such as a copper wire. In other words, at least the wiring portion 53 of the conductor 50 is made of a material that can deform in accordance with the deformation of the attachment component 40.

[0033] In this embodiment, the mounting component 40 further includes a housing portion 44 and an opening 45, as shown in FIGS. 4, 5, and 6. The housing portion 44 is a space for housing the wiring portion 53 inside the mounting component 40. The opening 45 is formed as a groove dug from the outer surface of the mounting component 40 toward the housing portion 44 on the inside, and connects the housing portion 44 to the outside of the mounting component 40. In this case, the wiring portion 53 is inserted into the housing portion 44 through the opening 45, for example, after the mounting component 40 is manufactured by, for example, injection molding. Furthermore, the wiring portion 53 can be inserted into and removed from the housing portion 44 through the opening 45. Therefore, the conductor 50 including the wiring portion 53 is configured to be easily replaceable. The wiring portion 53 may also be configured to be embedded in the mounting component 40 by, for example, insert molding.

[0034] An operator can attach and remove the additional part 2 to the paint gun 10 and muzzle 30, for example, as shown in FIG. 7 . In the example of FIG. 7 , the muzzle 30 includes a muzzle body 31 and a cap 32. The cap 32 is configured to be detachably attached to the muzzle body 31 by screws. In this configuration, when attaching the additional part 2 to the paint gun 10 and muzzle 30, the operator passes the holding portion 41 of the attachment part 40 through the tip of the muzzle body 31 and then screws the cap 32 onto the muzzle body 31 to secure it. Then, the operator passes the screw 90 through the threaded hole 423 and turns the screw 90 using a general tool such as a screwdriver to screw it into the bottom surface of the paint gun 10. This attaches the additional part 2 to the paint gun 10 and muzzle 30. When removing the additional part 2 from the paint gun 10 and muzzle 30, the operator reverses the procedure described above for attachment. As described above, according to this embodiment, the worker can easily attach and detach the additional part 2 to and from the paint gun 10 and the muzzle 30 without using any special tools.

[0035] Next, an example of an additional part 2A corresponding to the long muzzle 30A will be described with reference to Figures 8 and 9. The additional part 2A corresponding to the long muzzle 30A has the same configuration as the additional part 2 corresponding to the angle muzzle 30, but the specific shape of some of the configurations is different. Among the configurations of the additional part 2A corresponding to the long muzzle 30A, the same configurations as those of the additional part 2 corresponding to the angle muzzle 30 are given the same reference numerals and the description thereof will be omitted.

[0036] The additional part 2A has an attachment part 40A instead of the attachment part 40 of the additional part 2 described above. Although not shown in FIGS. 8 and 9, the additional part 2A has an internal conductor 50 and resistor 60, similar to the additional part 2 described above. The attachment part 40A has a holding part 41A instead of the holding part 41 of the attachment part 40 described above. The holding part 41A has the function of holding the long muzzle 30A, and is formed in a long cylindrical shape corresponding to the long muzzle 30A. The holding part 41A holds the long muzzle 30A by passing the long muzzle 30A inside the cylindrical inside of the holding part 41A.

[0037] According to the above configuration, the additional parts 2, 2A applicable to the electrostatic coating apparatus 1 are additional parts applicable to the electrostatic coating apparatus 1 having the paint gun 10 and the muzzle 30, 30A attached to the tip of the paint gun 10. The additional parts 2, 2A include the attachment parts 40, 40A and the conductor 50. The attachment parts 40, 40A are parts attached to the paint gun 10 and the muzzle 30, 30A, and have holding parts 41, 41A, a support part 42, and a connection part 43. The holding parts 41, 41A are formed in a cylindrical shape and receive the muzzle 30, 30A to hold the muzzle 30, 30A. The support part 42 supports the paint gun 10. The connection part 43 connects the holding parts 41, 41A and the support part 42.

[0038] The conductor 50 is made of a conductive material, and when the attachment parts 40, 40A are attached to the paint gun 10 and the muzzle 30, 30A, the tip side is exposed at the tip side of the muzzle 30, 30A and the base side is connected to ground. The conductor 50 has a wiring portion 53, which is a wiring path from the tip side to the base side, passing through the inside of the attachment parts 40, 40A.

[0039] Here, a high voltage received from the electrode 13 is applied to the conductor 50 built into the additional components 2, 2A. Therefore, if there are gaps between the mounted components 40, 40A due to joints connecting the components, there is a possibility that dielectric breakdown will occur in the mounted components 40, 40A.

[0040] Therefore, according to this embodiment, the holders 41, 41A, support portions 42, and connection portions 43 of the attachment parts 40, 40A are formed seamlessly as a single unit using electrically insulating materials. This prevents the presence of seams connecting the holders 41, 41A, support portions 42, and connection portions 43, thereby preventing dielectric breakdown at the seams. As a result, by using the additional parts 2, 2A of this embodiment, the electric field strength near the electrode 13 can be safely increased in a paint spray gun 10 equipped with an angle muzzle 30 or a long muzzle 30A at its tip.

[0041] The attachment parts 40, 40A are configured to be detachable from the paint gun 10 and the muzzle 30, 30A. Therefore, the attachment parts 2, 2A can be removed when replacing the muzzle 30, 30A or the nozzle 12, or when cleaning when changing paint colors, improving maintainability.

[0042] The attachment parts 40, 40A are made of flexible materials. As a result, the attachment parts 40, 40A can be deformed, such as by bending, to attach and detach the additional parts 2, 2A to and from the paint gun 10 and the muzzle 30, 30A. This improves the ease of attaching and detaching the additional parts 2, 2A to and from the paint gun 10 and the muzzle 30, 30A.

[0043] Furthermore, the attachment parts 40, 40A are made of flexible materials. Therefore, even if the paint gun 10 has some unevenness in the area where it comes into contact with the attachment parts 40, 40A, the attachment parts 40, 40A can be attached by deforming to fit the unevenness. Therefore, there is no need to adjust the shape of the attachment parts 40, 40A to fit the small unevenness of the paint gun 10, and common attachment parts 40, 40A can be used for paint guns 10 with slightly different surface uneven shapes. As a result, the number of additional parts 2, 2A to be stored and the labor required for management can be reduced.

[0044] Furthermore, the wiring section 53 is made of a member that can deform in accordance with the deformation of the attachment parts 40, 40A. This prevents damage such as breakage of the wiring section 53 even if the attachment parts 40, 40A are bent when attaching or detaching the additional parts 2, 2A to or from the paint gun 10 and the muzzle 30, 30A, particularly when attaching them. Therefore, it is no longer necessary to require precise work from the worker when attaching the additional parts 2, 2A to the paint gun 10 and the muzzle 30, 30A, and as a result, workability can be improved.

[0045] The above-described embodiments are not limited to the embodiments described above and illustrated in the drawings, and may be modified as appropriate within the scope of the invention. [Explanation of symbols]

[0046] 1...electrostatic coating device, 2, 2A...additional parts, 10...painting gun, 30...muzzle, angle muzzle, 30A...muzzle, long muzzle, 40, 40A...attachment parts, 41, 41A...holding part, 42...support part, 43...connection part, 50...conductor, 53...wiring part

Claims

1. The present invention is applied to an electrostatic coating device having a coating gun and a muzzle attached to the tip of the coating gun, a holding portion formed in a cylindrical shape into which the muzzle is inserted and which holds the muzzle; a support portion that supports the paint gun; a connecting portion that connects the holding portion and the support portion, an attachment component, the holding portion, the support portion, and the connection portion being seamlessly formed as a single piece using an electrically insulating material, the attachment component being attached to the spray gun and the muzzle; a conductor made of a conductive material, the conductor having a tip end exposed at the tip end of the muzzle and a base end connected to ground when the attachment part is attached to the spray gun and the muzzle, and a wiring path from the tip end to the base end passing through the inside of the attachment part; An additional component applicable to an electrostatic coating device having the above structure.

2. The attachment part is configured to be detachable from the paint gun and the muzzle. An additional part applicable to the electrostatic coating device according to claim 1.

3. The attachment part is made of a flexible material. An additional part applicable to the electrostatic coating device according to claim 1 or 2.

4. The wiring section is made of a member that is deformable in accordance with the deformation of the mounting component. An additional part applicable to the electrostatic coating device according to claim 3.

5. Paint gun and a muzzle attached to the tip of the paint gun; an additional part attached to the spray gun and the muzzle; The additional part is a holding portion formed in a cylindrical shape into which the muzzle is inserted and which holds the muzzle; a support portion that contacts the paint gun; a connection portion that connects the holding portion and the support portion; a mounting part formed seamlessly as a single piece from an electrically insulating material; a conductor made of a conductive material, the conductor having a tip end exposed at the tip end of the muzzle and a base end connected to ground when the attachment part is attached to the spray gun and the muzzle, and a wiring path from the tip end to the base end passing through the inside of the attachment part; An electrostatic coating device having:

Images