JP3984920B2 - Electrostatic coating equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
According to the present invention, after the coating material is once supplied from the supply source to the intermediate storage mechanism, the coating material is supplied to the coating gun in a state where the supply source and the intermediate storage mechanism are electrically cut off. It relates to painting equipment.
[0002]
[Prior art]
For example, a voltage block method is known as a method of applying a high voltage to a conductive paint to apply electrostatic coating to an object to be coated such as an automobile body. In this method, after the conductive paint is once introduced into an intermediate storage tank (intermediate storage mechanism) that is insulated from the ground potential, the supply path that connects the intermediate storage tank and the paint supply source is washed and cleaned. Dry to form a voltage block. In this state, an electrostatic coating operation is performed on an object to be coated by supplying a conductive paint to which a high voltage is applied from the intermediate storage tank to the coating gun.
[0003]
For example, Patent Document 1 is known as an electrostatic coating apparatus used for this type of coating. In Patent Document 1, as shown in FIG. 7, a pump 1 is provided as an intermediate storage mechanism, and a paint inflow port 1 a of the pump 1 can be connected to a paint supply path 2 via an insulating mechanism 3. The conductive paint is filled from the supply source 4. On the other hand, a predetermined amount of conductive paint is pumped to the coating machine 5 from the paint discharge port 1b of the pump 1.
[0004]
The pump 1 includes a piston 6, and the piston 6 can be advanced and retracted by high-pressure air supplied from an air supply source 7 through a pressure adjustment valve 8. The moving speed of the piston rod 6a connected to the piston 6 is detected by a non-contact sensor 9, and the flow rate of the conductive paint supplied to the coating machine 5 is measured based on the moving speed of the piston rod 6a. Is done.
[0005]
Then, the measured flow rate of the conductive paint and the flow rate set in advance according to the paint discharge amount of the coating machine 5 are compared, and the pressure of the high-pressure air supplied to the pump 1 is determined according to the difference value. The pressure is adjusted variably through the pressure adjusting valve 8. Accordingly, the pump 1 can be miniaturized and the quantitative property of the pump 1 can be ensured.
[0006]
[Patent Document 1]
Japanese Patent Laid-Open No. 6-60452 (FIG. 1)
[0007]
[Problems to be solved by the invention]
By the way, in the above-mentioned Patent Document 1, the electrostatic coating apparatus is often attached to, for example, a robot to automatically perform electrostatic coating work. For this reason, it is desired to mount the entire electrostatic coating apparatus compactly with respect to the robot, and it is necessary to dispose the insulating mechanism 3 close to the pump 1.
[0008]
At that time, the pump 1 is made of an insulating resin material in order to prevent liquid junction due to the conductive paint. However, a high voltage generating means is incorporated in order to apply a high voltage to the conductive paint, and there is a possibility that a high voltage leaks to the insulating mechanism 3 along the surface of the pump 1 and a dielectric breakdown occurs.
[0009]
Thus, conventionally, it has been pointed out that the pump 1 and the insulating mechanism 3 must be disposed at a relatively large distance apart, and the entire electrostatic coating apparatus cannot be made compact.
[0010]
The present invention solves this type of problem. With a simple configuration, a desired creepage distance can be secured to prevent high-voltage leakage, and the entire apparatus can be configured compactly. An object is to provide an electropainting device.
[0011]
[Means for Solving the Problems]
In the electrostatic coating apparatus according to the present invention, an intermediate storage mechanism that is disposed at least between a coating material supply source and a coating gun and temporarily stores the coating material, and a coating material flow path that connects the supply source and the intermediate storage mechanism. An insulating mechanism that electrically cuts off the supply source and the intermediate storage mechanism, and a size in plan view in which one surface is disposed in close proximity to the intermediate storage mechanism. And a smaller insulating plate. An insulating mechanism is mounted on the surface of the insulating plate opposite to the intermediate storage mechanism (the other surface) in addition to the intermediate storage mechanism.
[0012]
Thus, since the insulating plate is interposed between the intermediate storage mechanism and the insulating mechanism, it is possible to ensure a sufficient creepage distance along the insulating plate. This makes it possible to prevent leakage of high voltage and to arrange the insulating mechanism as close as possible to the intermediate storage mechanism. Accordingly, the entire electrostatic coating apparatus can be configured in a compact manner, and can be easily mounted on a robot or the like, for example, and the efficiency of electrostatic coating work can be easily achieved.
[0013]
The intermediate storage mechanism includes a cylinder container, a piston that is slidably reciprocated in the cylinder container, and a piston drive unit that is connected to a piston rod provided in the piston and moves the piston back and forth. I have. Here, the cylinder container and the piston rod are made of an insulating resin material, and it is possible to satisfactorily ensure the insulation of the entire intermediate storage mechanism.
[0014]
Furthermore, while the attachment surface of the intermediate storage mechanism is disposed at the attachment site, an insulation mechanism is disposed on the surface side opposite to the attachment surface of the intermediate storage mechanism via an insulation plate. The intermediate storage mechanism and the insulating mechanism are covered with an insulating cover member, and the insulating cover member is detachable from the insulating mechanism side.
[0015]
Thus, since the insulating cover member is provided so as to cover the intermediate storage mechanism, the insulation of the intermediate storage mechanism is further improved. In addition, the insulating cover member is detachable from the insulating mechanism side, and workability such as maintenance of the insulating mechanism is effectively improved.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a schematic configuration explanatory diagram of an electrostatic coating apparatus 10 according to an embodiment of the present invention.
[0017]
The electrostatic coating apparatus 10 includes a color change valve mechanism 12 that is grounded. The color change valve mechanism 12 controls the supply of drying air (A), water (W), cleaning liquid (S), and the like. One cleaning valve 14 and a plurality of paint valves 16a, 16b and 16c capable of supplying conductive paints of different colors are provided. A block valve mechanism 20 is connected to the color change valve mechanism 12 via a supply path 18a, and a first discharge path 23 is connected to the supply path 18a via a first dump valve 21.
[0018]
The block valve mechanism 20 has a resin-made electrically insulating conduit (supply passage) 18b, and switching valves 22a and 22b are connected to both ends of the electrically insulating conduit 18b. The switching valve 22a on the inlet side switches between the color change valve mechanism 12 and the second cleaning valve 24 that controls the supply of air (A), water (W), cleaning liquid (S), etc., and the switching valve on the outlet side. The intermediate storage tank (intermediate storage mechanism) 26 is switched through the second discharge path 25 and the supply path 18c by 22b.
[0019]
The intermediate storage tank 26 includes a cylinder container 26a made of an insulating resin, and a cylinder chamber 30 for injecting conductive paint and cleaning liquid is formed in the cylinder container 26a via a piston 28. The cylinder chamber 30 communicates with an injection hole 32 and a discharge hole 34, and the injection hole 32 is disposed above the discharge hole 34. A servo motor 36 is connected to a rod 28a made of an insulating resin extending from the piston 28 via a ball screw means 37, and the piston 28 can advance and retreat in the direction of arrow A.
[0020]
A coating gun 40 is connected to the cylinder chamber 30 of the intermediate storage tank 26 via a delivery path 38. The coating gun 40 includes a second dump valve 42 and a trigger valve 44 and is connected to a high voltage applying unit (not shown). The second dump valve 42 is connected to a third discharge path 46 for discharging the drainage liquid containing the conductive paint and the cleaning liquid generated during cleaning to the outside of the delivery path 38.
[0021]
A third cleaning valve 48 that controls the supply of air (A), water (W), cleaning liquid (S), and the like is connected to the third discharge path 46.
[0022]
As shown in FIGS. 2 and 3, a mounting plate (attachment part) 62 is fixed to a movable part of the electrostatic coating apparatus 10, for example, a robot arm 60, and an insulating cradle 64 is fixed to the mounting plate 62. Is done. An insulating support base 66 is screwed to the receiving base 64, for example, and the cylinder container 26a constituting the intermediate storage tank 26 is supported in a horizontal posture via the support base 66.
[0023]
An insulating plate 68 is fixed on the support base 66, and switching valves 22a and 22b are mounted on the insulating plate 68 on the opposite side of the intermediate storage tank 26 by screwing or the like.
[0024]
An insulating cover 70 is detachably screwed to the cradle 64 so as to cover the intermediate storage tank 26 and the block valve mechanism 20. As shown in FIG. 4, the cradle 64 is provided with groove portions 64a on both sides in the diameter direction (arrow B direction) of the cylinder container 26a, and each groove portion 64a extends in the axial direction of the cylinder container 26a (in FIG. Direction). The insulating cover 70 has a U-shaped cross section, and both end portions 70a directed downward are formed in a thin shape. The both end portions 70a are inserted into the respective groove portions 64a, and the both end portions 70a and the pedestal 64 are fixed by bolts 71.
[0025]
As shown in FIGS. 2 and 3, the color change valve mechanism 12, the second cleaning valve 24, and the servo motor 36 are mounted on the mounting plate 62. A ball screw 72 constituting a ball screw means 37 is coaxially connected to the rotation shaft 36a of the servo motor 36. The ball screw 72 extends in the direction of arrow A and is rotatably supported by the frame member 74. Is done.
[0026]
The frame member 74 is provided with linear guides 76 located on both sides of the ball screw 72, and a movable table 78 is disposed on the linear guide 76 so as to freely advance and retract. The movable table 78 includes a nut portion 80 into which the ball screw 72 is screwed. The rear end of the rod 28a is fixed to the movable table 78.
[0027]
The robot arm 60 is maintained in a substantially horizontal posture when performing a painting operation, and in this substantially horizontal posture, the discharge hole portion 34 of the intermediate storage tank 26 is always disposed below the injection hole portion 32. Yes.
[0028]
The operation of the electrostatic coating apparatus 10 configured as described above will be described below.
[0029]
First, the supply path 18a, the electrically insulating pipe line 18b, and the supply path 18c are connected via the switching valves 22a and 22b of the block valve mechanism 20. Then, for example, the paint valve 16a of the color change valve mechanism 12 is opened, and the servo motor 36 of the intermediate storage tank 26 is driven.
[0030]
For this reason, as shown in FIG. 1, the conductive paint of a predetermined color is pumped from the paint valve 16a. The conductive paint is filled into the cylinder chamber 30 of the cylinder container 26a through the supply path 18a, the electrically insulating pipe line 18b, and the supply path 18c, and is further supplied to the coating gun 40 through the delivery path 38.
[0031]
When filling of the cylinder chamber 30 of the cylinder container 26a with the conductive paint is completed, the block valve mechanism 20 is cleaned. Specifically, as shown in FIG. 5, the switching valves 22a and 22b of the block valve mechanism 20 are switched, and the second cleaning valve 24 is connected to the second discharge path 25 via the electrically insulating conduit 18b. The
[0032]
Accordingly, when the cleaning liquid (water or thinner) is supplied from the second cleaning valve 24, the inside of the electrically insulating conduit 18 b is cleaned, and the waste liquid is discharged to the second discharge path 25. Further, air is supplied from the second cleaning valve 24 to dry the inside of the electrically insulating conduit 18b, and electrical insulation is made between the switching valves 22a and 22b.
[0033]
Next, as shown in FIG. 6, the trigger valve 44 is opened, and the piston 28 moves in the direction of the arrow A <b> 2 under the drive action of the servo motor 36. Paint is pumped. For this reason, the conductive paint is discharged from the coating gun 40 via the trigger valve 44, and a high voltage is applied to the conductive paint, whereby electrostatic painting is performed on the object to be coated.
[0034]
In this case, in this embodiment, as shown in FIG. 2, a cylinder container 26a constituting the intermediate storage tank 26 is disposed on the receiving base 64, and an insulating plate 68 is interposed above the cylinder container 26a. A block valve mechanism 20 is arranged.
[0035]
As described above, since the insulating plate 68 is interposed between the intermediate storage tank 26 and the block valve mechanism 20, a sufficient circular distance can be secured along the insulating plate 68. Accordingly, it is possible to prevent leakage of high voltage and to arrange the block valve mechanism 20 as close to the intermediate storage tank 26 as possible.
[0036]
Therefore, the entire electrostatic coating apparatus 10 can be easily configured compactly, and can be mounted compactly on the robot arm 60, so that the effect of improving the efficiency of the electrostatic coating work can be obtained.
[0037]
Moreover, the cylinder container 26a and the rod 28a which comprise the intermediate | middle storage tank 26 are comprised with the insulating resin material. For this reason, it becomes possible to ensure the insulation of the whole intermediate storage tank 26 satisfactorily.
[0038]
Further, the insulating cover 70 is detachably screwed to the cradle 64 so as to cover the cylinder container 24 a and the block valve mechanism 20. For this reason, the insulation of the intermediate | middle storage tank 26 improves further. Moreover, the insulating cover 70 can be removed from the block valve mechanism 20 side (that is, upward), and there is an advantage that workability such as maintenance of the block valve mechanism 20 is effectively improved.
[0039]
In the present embodiment, the robot arm 60 is used as the movable part of the electrostatic coating apparatus 10. However, the present invention is not limited to this. For example, the intermediate portion on the transport table that is movable in three orthogonal axes. A storage tank 26 may be attached.
[0040]
【The invention's effect】
In the electrostatic coating apparatus according to the present invention, since the insulating plate is interposed between the intermediate storage mechanism and the insulating mechanism, a sufficient creepage distance can be secured along the insulating plate. This makes it possible to prevent leakage of high voltage and arrange the insulating mechanism as close as possible to the intermediate storage mechanism. Therefore, the entire electrostatic coating apparatus can be configured in a compact manner, and can be easily mounted on a robot or the like, for example, and the efficiency of electrostatic coating work can be easily achieved.
[Brief description of the drawings]
FIG. 1 is a schematic configuration explanatory diagram of an electrostatic coating apparatus according to an embodiment of the present invention.
FIG. 2 is a side view showing a state where an intermediate storage tank is attached to the robot arm of the electrostatic coating apparatus.
FIG. 3 is a plan view of the mounted state shown in FIG.
4 is a partial cross-sectional front view of the mounted state shown in FIG. 2. FIG.
FIG. 5 is an operation diagram for explaining a cleaning operation of a block valve mechanism constituting the electrostatic coating apparatus.
FIG. 6 is an operation diagram for explaining a painting operation by the electrostatic coating apparatus.
7 is a schematic configuration explanatory diagram of a pump of an electrostatic coating apparatus according to Patent Document 1. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Electrostatic coating apparatus 12 ... Color change valve mechanism 14, 24 ... Washing valve 16a-16c ... Paint valve 18a, 18c ... Supply path 18b ... Electrical insulation pipe line 20 ... Block valve mechanism 22a, 22b ... Switching valve 26 ... Intermediate reservoir 26a ... Cylinder container 28 ... Piston 30 ... Cylinder chamber 32 ... Injection hole 34 ... Discharge hole 36 ... Servo motor 40 ... Paint gun 60 ... Robot arm 62 ... Mounting plate 64 ... Receiver 64a ... Groove 66 ... Insulation Support stand 68 ... insulating plate 70 ... insulating cover 70a ... end 71 ... bolt

Claims (4)

An intermediate storage mechanism that is disposed at least between the paint supply source and the paint gun, and temporarily stores the paint;
An insulating mechanism that is provided in a paint flow path connecting the supply source and the intermediate storage mechanism, and electrically cuts off the supply source and the intermediate storage mechanism;
While one surface is disposed in close proximity to the intermediate storage mechanism,
On the other surface, an insulating plate on which the insulating mechanism is mounted in addition to the intermediate storage mechanism;
Equipped with a,
The electrostatic coating apparatus according to claim 1, wherein the insulating plate is at least smaller in plan view than the intermediate storage mechanism . The electrostatic coating apparatus according to claim 1, wherein the insulating mechanism includes an electrically insulating conduit,
A first switching valve connected to an end of the electrically insulating conduit on the supply source side and connected to the paint flow path connected to the supply source;
A second switching valve connected to the end of the electrically insulating conduit on the side of the intermediate storage mechanism and connected to the paint flow channel connected to the intermediate storage mechanism;
Have One of the first switching valve and the second switching valve is connected to a discharge path connected to the waste liquid discharge side, and the other is connected to a flow path connected to a cleaning valve.
The electrostatic coating apparatus, wherein the first switching valve and the second switching valve are fixed on the insulating plate. The electrostatic coating apparatus according to claim 1 or 2 , wherein the intermediate storage mechanism includes a cylinder container,
A piston that is reciprocally slidable in the cylinder container;
A piston drive unit connected to a piston rod provided on the piston and moving the piston back and forth;
With
The electrostatic coating apparatus, wherein the cylinder container and the piston rod are made of an insulating resin material. In the electrostatic coating apparatus according to any one of claims 1 to 3, an attachment surface of the intermediate storage mechanism is arranged at an attachment site, and on the surface side opposite to the attachment surface of the intermediate storage mechanism, The insulating mechanism is arranged via the insulating plate,
An electrostatic coating apparatus comprising an insulating cover member that covers the intermediate storage mechanism and the insulating mechanism and is detachable from the insulating mechanism side.

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