JPH10128172A - Work electrifying type electrostatic coating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable work electrifying type electrostatic coating by utilizing existing air supply and exhaust equipment by allowing an insulating support to advance from the floor surface of a coating booth to raise a truck when the truck having a work placed thereon is stopped at a predetermined position and applying high voltage to the work through an electrode attachment. SOLUTION: When a truck 7 having a work W placed thereon is stopped on a conveyor 6 at a predetermined position, the insulating support 8 attached to a base 9 advances from a floor surface to raise the truck 7 from the conveyor 6. When this truck 7 rises up to a position separated by a predetermined insulating distance or more, a high voltage supply permitting signal is outputted to a high voltage controller from a safety device by the detection signal from a height detection means and the power supply voltage on a primary side supplied to a high voltage generating circuit is raised and high voltage is applied to the work W through the electrode attachment 11 formed to the upper end of the insulating support 9. Whereupon, an electrostatic field is formed between the work W and an earthed coating machine 4 and the coating material sprayed from the coating machine 4 is electrostatically applied to the work W.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of applying a high voltage to a work to form an electrostatic field between the work and a grounded coating machine, and to apply paint sprayed from the coating machine to the work. The present invention relates to a work-applied electrostatic coating apparatus for performing electrocoating.

[0002]

2. Description of the Related Art In the case of electrostatically coating a conductive paint such as a water-based paint or a metallic paint, in order to eliminate troublesome insulation of a painter and its paint supply system, the painter is connected to a ground and a high work is applied to a work. There has been proposed a work-applied electrostatic coating apparatus in which a voltage is applied to form an electrostatic field between the two, and a paint sprayed from a coating machine is electrostatically applied to the work. And the conventional work electrification type electrostatic coating device 50 is:
As shown in FIG. 8, a lifter 53 that lifts the work W from the conveyor 52 while retracting the work W on the carriage 51 and retreats to the side of the conveyor 52 is provided in the coating zone. According to this, when the cart 51 on which the work W is placed arrives at the painting zone, the cart 51 is moved by the lifter 53 to the conveyor 5.
Since the work W can be retracted to the side and supported in an insulated state, if a high voltage supplied from the high voltage generating circuit 55 is applied to the work W, the work W can be separated from the grounded coating machine 54. Therefore, even when the conductive paint is electrostatically applied, the paint sprayed from the paint machine 54 is applied to the work W without taking any measures against the insulation of the paint machine 54 and its paint supply system. It can be electrostatically coated.

[0003]

However, an existing painting line for painting an automobile body, for example, generally has an air supply chamber 61 formed in the ceiling as shown in FIG.
The work W is placed on the carriage 51 by placing the work W on the carriage 51, and the work W is placed on the carriage 51 by allowing the conditioned air to flow down to the inside of the painting room 62 and sucking out the contaminated air containing the paint mist. Since the work W is painted while being conveyed by 52, the lifter 53 is installed in the painting booth 64, or the work W is placed at a side position of the conveyor 52 laid in the painting chamber 62. It is extremely difficult to secure a space for evacuation and painting.

Further, even if the coating booth 64 can be expanded to secure a space for painting by retreating the work W to the side of the conveyor 52 in the booth, the interior of the expanded coating room 62 can be secured. Air supply and exhaust equipment for discharging contaminated air in the coating chamber 62 must be separately installed beside the conveyor 52.
Existing air supply / exhaust equipment formed along the conveyor 52 cannot be used as it is. Therefore, it is difficult to install a work-applied electrostatic coating apparatus on an existing coating line, regardless of the case where a new coating line is installed.

[0005] Therefore, an object of the present invention is to make it possible to perform work-applied electrostatic painting by directly using a supply / exhaust facility formed in an existing painting line.

[0006]

In order to solve this problem, the present invention conveys a truck on which a work is placed by a conveyor laid on the floor of a coating room and stops the truck at a predetermined position. In a work-applied electrostatic coating device that applies a high voltage to the work while supporting it insulated and electrostatically applies paint sprayed from a grounded coating machine to the work, the work is stopped at a predetermined position by a conveyor. An insulating column that lifts the lifted trolley to a position separated by a predetermined insulating distance or more from the conveyor is disposed so as to be able to advance and retreat upward from the floor of the coating room, and the upper end thereof has the insulating column. An electrode attachment that is electrically connected to the work when the sheet is advanced is formed, and the insulating pillar is advanced to the electrode attachment so that the bogie is separated from the conveyor by a predetermined insulation distance or more. When increased to location, characterized in that the control device for applying a high voltage to the work via the electrode attachment is connected.

According to the present invention, when the cart on which the workpiece is placed is stopped at a predetermined position, the insulating support posts advance from the floor of the coating booth with respect to the cart, and the cart is separated from the conveyor by a predetermined insulating distance or more. It is lifted to a position away and is insulated and supported. When the control device is turned on in this state, a high voltage of, for example, -60 to -90 kV is applied to the work via an electrode attachment formed at the upper end of the insulating support.
In this case, if the bogie is provided with a safety device that does not supply a high voltage unless the bogie is lifted off the conveyor and separated by a predetermined insulating distance or more, a high voltage is not applied before the bogie moves away from the predetermined insulating distance. . Therefore, it is possible to prevent the occurrence of sparks and high voltage leakage.

[0008] When a high voltage is applied to the work, an electrostatic field is formed between the work and a grounded coating machine. Is electrostatically applied. At this time, a paint adhesion preventing cover that moves forward and backward in conjunction with the insulating support column is provided, and if it is advanced to a position that covers the insulating support column so that the paint mist does not adhere to the insulating support column that has advanced onto the floor, overspray has occurred. The paint mist does not adhere to the insulating support, and the paint adhesion preventing cover retreats in conjunction with the retreat of the insulating support below the floor, so that there is no hindrance to the traveling of the bogie. In addition, even if the insulating column malfunctions and the position of the bogie is lowered while a high voltage is being applied to the work, the provision of the above-mentioned safety device prohibits the supply of the high voltage. Generation and leakage of high voltage can be prevented beforehand.

When the painting is completed, the control device is turned off and the high voltage applied to the work is cut off, and then the insulating column is retracted under the floor. As a result, the carriage is returned to the conveyor and transferred to the next process. When the insulating pillar is retracted under the floor, the electrode attachment formed at the upper end thereof is almost flush with the grating laid on the floor surface, and closes the opening formed in the grating. In addition, when performing maintenance in the coating machine or the coating booth, the operator does not accidentally step on the opening or trip over the opening. In this way, the insulating pillar is retracted under the floor, so when installing it in the existing painting booth where the exhaust room is formed under the floor of the painting room, it can be attached to the beam installed under the floor of the painting room. And the supply and exhaust equipment of the coating booth can be used as it is.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view showing a work-applied electrostatic coating apparatus according to the present invention, FIGS. 2 (a) and 2 (b) are plan views showing examples of the arrangement of insulating posts, and FIGS. 5 (a) and 5 (b) are explanatory views showing the operation of the device of the present invention.

In FIG. 1, reference numeral 1 denotes a paint mist over-sprayed from a coating machine 4 installed in the coating chamber 3 by flowing conditioned air from an air supply chamber 2 formed on the ceiling into the coating chamber 3. A coating booth that sucks contaminated air into an exhaust chamber 5 under the floor, and guides the conveyor 7 with a conveyor chain 6a that pulls a carriage 7 on which a work W is placed on the floor surface F of the coating chamber 3. A conveyor 6 comprising a conveyer rail 6b for running is laid. The work-applied electrostatic coating apparatus R of this embodiment stops the carriage 7 conveyed by the conveyor 6 at a predetermined position and insulates and supports the carriage 7 from the work W placed on the carriage 7. By applying a voltage, the paint sprayed from the grounded coating machine 4 is electrostatically applied to the work W.

More specifically, a base 9 on which an insulating column 8 for insulatingly supporting the carriage 7 stopped at a predetermined position and lifting the carriage 7 above the conveyor 6 is attached to the guide rails 14, 14.
Are disposed so as to be able to move up and down by the cylinders 10 and 10 along the floor, and are disposed so as to be able to advance and retreat upward from the floor surface F of the coating chamber 3. The electrode attachment 11 is formed to be electrically connected to the work W when it is advanced. In addition, as the conveyer 6, a shuttle conveyer or the like that quickly sends the cart 7 to the predetermined position and quickly pulls out the trolley 7 from the predetermined position is used. When the carriage 7 is conveyed by the conveyor 6 and stopped at a predetermined position, the cylinder 10 is extended, the base 9 is raised, and the insulating posts 8, 8 attached to the base 9 are moved upward from the floor F. , The carriage 7 is lifted to a position separated from the conveyor 6 by a predetermined insulating distance, and when the coating is completed, the cylinder 10 is contracted and the base 9 is lowered and attached to the base. Insulating posts 8, 8
Is retracted under the floor, and the cart 7 is lowered onto the conveyor 6.

As shown in FIG. 2A, the conveyor chain 6a of the conveyor 6 is connected to the conveyor rails 6b, 6b.
In the case where the electrodes are arranged to be offset from the center to one side, two insulating pillars 8 and 8 are erected in front and rear, and the area of the electrode attachment 11 formed at the upper end thereof is increased in order to stably support the work W. Good. Also, as shown in FIG. 2B, the conveyor chain 6a of the conveyor 6 is
b, 6b, the insulating posts 8,
8 ... should be provided on the base 9 in four front, rear, right and left directions. As shown in FIGS. 3 and 4, a grating G is provided on the floor F of the coating booth 1, and an opening H is formed in the grating G for moving the insulating support 8 forward and backward.
When the insulating support 8 is retracted under the floor, the electrode attachment 11 formed at the upper end thereof is substantially flush with the grating G and covers the opening H. In the exhaust chamber 5, a cover 12 for preventing paint mist from adhering to each of the cylinders 10 and the base 9 disposed below the grating G is disposed so as to cover these front, rear, left and right. And the cover 12
A shower pipe 13 through which cleaning water flows down is provided at the upper end of the cover 12 so that paint mist adhering to the cover 12 is washed away.

Further, the cylinder 10 is extended to the electrode attachment 11 formed at the tip of the insulating column 8 to advance the insulating column 8 on the floor.
The control device 20 that applies a high voltage to the work W via the electrode attachment 11 when connected to a position at least a predetermined insulating distance from the control unit 20 is connected. The control device 20 includes a high-voltage generating circuit 21 and a ground switch 22 disposed in the insulating support 8 and a high-voltage controller 23 disposed outside the painting booth 1. A safety device 24 for supplying a high voltage only when the carriage 7 is lifted from the conveyor 6 to a height more than a predetermined insulation distance is connected. The safety device 24 is connected to height detecting means 25 for detecting that the cart 7 is lifted from the conveyor 6 and separated from the conveyor 6 by a predetermined insulation distance or more. Outputs a high voltage supply allowance signal to the high voltage controller 23 when the vehicle 7 is separated from the conveyor 6 by a predetermined insulation distance or more, and outputs a high voltage supply prohibition signal when the carriage 7 is not separated from the conveyor 6 by a predetermined insulation distance or more. It is configured to output. The height detecting means 2
Reference numeral 5 denotes a limit switch that is turned on by being brought into contact with the raised base 9 when the cart 7 is lifted to a position separated from the conveyor 6 by a predetermined insulation distance or more as shown in FIG. Is used, but the present invention is not limited to this, and any detection means may be employed.

The high-voltage controller 23 confirms that a high-voltage generation permission signal has been output at the start of painting, and then supplies a low-voltage (for example, −24 V) on the primary side to the high-voltage generation circuit 21. At the end of painting, the primary voltage to the high voltage generation circuit 21 is cut off, and the ground switch 22 is turned on to release the electric charge accumulated in the work W to the ground. When a high voltage generation prohibition signal is output from the safety device 24 during application of a high voltage, not only does the primary voltage to the high voltage generation circuit 21 be cut off and the ground switch 22 is turned on, but also an alarm is generated. It is designed to sound and inform the worker of the occurrence of an emergency. Further, the high voltage generating circuit 21 is configured to boost the low voltage on the primary side to about −60 to −90 kV and supply it to the electrode attachment 11, whereby a high voltage is applied to the work W.

The above is an example of the configuration of the present invention, and its operation will be described next with reference to FIG. First, when the workpiece W is carried on the carriage 7 and transported, the cylinder 10 is in a contracted state as shown in FIG. 5A and the insulating support 8 is stored under the floor, so that the carriage 7 travels. There is no problem. When the carriage 7 travels on the conveyor 6 and stops at a predetermined position, as shown in FIG.
0 is extended and the base 9 rises and the base 9
The bogie 7 is lifted from the conveyor 6 by the insulating struts 8 because the insulating struts 8 attached to the vehicle advance upward from the floor surface.

When the cart 7 is lifted to a position at least a predetermined insulation distance from the conveyor 6, a detection signal is output from the height detecting means 25 to the safety device 24, and the safety device 24 sends the detection signal to the high-voltage controller 23. A high voltage supply permission signal is output. Based on this, the primary-side power supply voltage supplied to the high-voltage generating circuit 21 is boosted, and a high voltage of, for example, −60 to −90 kV is applied to the work via the electrode attachment 8 formed at the upper end of the insulating support 9. You. Therefore, when the cart 7 is not lifted from the conveyor 6 to a position more than a predetermined insulation distance, a high voltage is not applied, and the occurrence of sparks and leakage of the high voltage can be prevented beforehand. .

When a high voltage is applied to the work W, an electrostatic field is formed between the work W and the grounded coating machine 4, so that the paint sprayed from the grounded coating machine 4 Is electrostatically applied to the work W which is the opposite pole.
Here, while the high voltage is being applied to the workpiece W, for example, if the position of the bogie 7 is lowered due to malfunction of the cylinder 10,
This is detected by the height detecting means 25, and a high voltage generation prohibition signal is output from the safety device 24. At the same time, the supply of the high voltage to the work W is stopped urgently, the ground switch 22 is turned on, and the alarm is generated. The alarm is sounded to notify the worker of an emergency.

When the coating is completed, the primary-side power supply voltage to the high-voltage generating circuit 21 is cut off by the control signal output from the high-voltage controller 23 to stop the supply of the high voltage, and the ground switch 22 And the electric charge accumulated in the work W is released to the ground. Then, the cylinder 10 is contracted and the base 9 is lowered, and at the same time, the insulating support 8 is retracted under the floor of the coating room 3. As a result, as shown in FIG. 5A, the cart 7 is placed on the conveyor 6 and transferred to the next step. In addition, the insulating support 8
The electrode attachment 11 formed on the upper end of the opening G when being retracted under the floor of the coating room 3 is substantially flush with the grating G laid on the floor surface F, and the opening formed in the grating G is formed. Since the portion H is closed, a worker who performs maintenance work in the painting booth 1 does not accidentally step off the opening H. Then, since the insulating column 8 is retracted under the floor of the coating room 3, when the exhaust room 5 is installed in the existing painting booth 1 formed under the floor, beams installed under the floor of the coating room 3 and the like. And can be easily attached to the coating room.
The work W can be painted with the air supply chamber 2
In addition, the exhaust chamber 5 and any air supply / exhaust equipment attached thereto can be used as they are.

FIG. 6 is a front view showing another embodiment according to the present invention, and FIG. 7 is an enlarged view of a main part thereof. Parts common to FIGS. 1 to 5 are denoted by the same reference numerals. The detailed description is omitted. In this example, paint adhesion preventing covers 30, 30 which move forward and backward in conjunction with the insulating pillar 8 are provided. The paint adhesion preventing cover 30 is, for example, a hinge 3
1 and is connected to the base 9 via a link 32 so as to be openable and closable at the edge of the opening H. When the cylinder 10 is extended and the insulating support 8 is advanced onto the floor, it is interlocked with this. The insulating pillar 8 is opened so as to be erected on a side surface of the insulating pillar 8 so as to prevent paint from adhering to the surface of the insulating pillar 8. Further, when the insulating column 8 is retracted under the floor by contracting the cylinder 10, the opening H is closed in conjunction with this, and the cylinder is retracted to a position where it does not hinder the traveling of the carriage 7. . The safety device 24 of the control device 20 according to the present embodiment includes, as height detecting means 25 for detecting the height of the bogie 7, paint adhesion that has advanced in conjunction with the insulating support 8 when the insulating support 8 has advanced onto the floor. Prevention cover 3
A limit switch that is turned on after being brought into contact with 0 is used. Further, the paint adhesion preventing cover 30 is not limited to the type that opens and closes as described above, and a cylinder is integrally attached to the base 9 in advance so as to cover the periphery of the insulating support column 8. And may be moved up and down integrally with the base 9.

Furthermore, in the above description, the cylinder 1
Although the case where the cylinder 10 is arranged so as to raise the base 9 by extending 0 is described, the base 9 is moved through the floor 10 via the cylinder 10 so as to raise the base 9 by contracting the cylinder 10. It may be arranged so as to hang from the camera.

[0022]

As described above, according to the present invention, an insulating column for lifting a truck stopped at a predetermined position to a position separated from a conveyor by a predetermined insulating distance or more is placed under the floor so as to advance upward from the floor surface. Since it is provided, it is possible to perform work-applied electrostatic painting using the air supply and exhaust equipment as it is, without making significant improvements to the existing painting booth that has an exhaust chamber under the floor. It has a very good effect. Further, if the bogie is provided with a safety device that does not supply a high voltage unless the bogie is lifted off the conveyor and separated by a predetermined insulating distance or more, a high voltage is not applied before the bogie is separated from the predetermined insulating distance, and therefore, In addition, it is possible to prevent the occurrence of sparks and leakage of high voltage beforehand, and it is possible to perform the painting operation while ensuring safety. Further, when the insulating pillar is retracted under the floor, the electrode attachment formed at the upper end thereof is substantially flush with the grating laid on the floor surface, so as to close the opening formed in the grating. This makes it possible for workers to not accidentally step on their openings or trip over when performing maintenance inside the painting machine or painting booth, which is safe for workers and , Equipment installed under the grating can be protected. Furthermore, if a paint adhesion preventing cover which moves forward and backward in conjunction with the insulating support is provided, and the paint is prevented from adhering to the insulating support that has advanced onto the floor, the paint mist is advanced to a position covering the insulating support, so that overspray is achieved. There is also an effect that the paint mist that has adhered to the insulating support pillars is less likely to become dirty.

[Brief description of the drawings]

FIG. 1 is a front view showing a work charging type electrostatic coating apparatus according to the present invention.

FIGS. 2A and 2B are plan views showing examples of the arrangement of insulating posts.

FIG. 3 is a perspective view showing the operation of the insulating support.

FIG. 4 is a side view showing the operation of the insulating pillar.

FIGS. 5A and 5B are explanatory diagrams showing the operation of the device of the present invention.

FIG. 6 is a front view showing another embodiment.

FIG. 7 is an enlarged view of a main part thereof.

FIG. 8 is a front view showing a conventional work-applied electrostatic coating apparatus.

FIG. 9 is a front view showing a conventional painting booth.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Painting booth 3 ... Painting room R ... Work electrification type electrostatic coating apparatus 4 ... Painting machine 6 ... Conveyor 7 ... Dolly W ... Work 8 ... Insulation Prop 11: Electrode attachment F: Floor G: Grating H: Opening 20: Control device 24: Safety device 25: Height detecting means 30: Paint adhesion Prevention cover

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Tokuyasu Yamaguchi 1-9-9 Kakimotocho, Toyota City, Aichi Prefecture Inside Trinity Industry Co., Ltd.

Claims (4)

[Claims] 1. A carriage (7) on which a work (W) is placed is conveyed by a conveyor (6) laid on a floor (F) of a coating room (3), stopped at a predetermined position, and stopped at a predetermined position. A high voltage is applied to the work (W) in a state in which the work (W) is insulated and the paint sprayed from the grounded coating machine (4) is applied to the work (W).
In a work-applied electrostatic coating apparatus that electrostatically coats a trolley, a trolley (7) stopped at a predetermined position by a conveyor (6) is lifted to a position separated from the conveyor (6) by a predetermined insulating distance or more. A column (8) is disposed so as to be able to advance and retreat upward from the floor surface (F) of the coating room (3), and at the upper end thereof when the insulating column (8) is advanced. An electrode attachment (11) that is electrically connected to the work (W) is formed. The insulating support (8) is advanced into the electrode attachment (11), and a cart (7) is moved from the conveyor (6) to a predetermined position. And a control device (20) for applying a high voltage to the work (W) via the electrode attachment (11) when the control device (20) is elevated to a position separated by more than the insulation distance of the work. Electrostatic coating equipment. 2. An opening (H) for moving the insulating support (8) back and forth in a grating (G) disposed on a floor (F).
Is formed, and the electrode attachment (11) formed on the upper end of the insulating support (8) when it is retracted under the floor of the coating chamber (3) is substantially flush with the grating (G). The work-applied electrostatic coating device according to claim 1, wherein the work is configured to cover the opening (H). 3. The control device (20) is adapted to allow a high voltage to be supplied when the carriage (7) lifted by the insulating support (8) is separated from the conveyor (6) by a predetermined insulating distance or more. 3. An electrostatic painting apparatus according to claim 1, further comprising an apparatus (24). 4. The insulating post (8) prevents paint mist from adhering when the insulating post (8) advances on the floor.
And a paint adhesion preventing cover (30) which retracts to a position where it does not hinder the traveling of the bogie (7) when the insulating support (8) retreats below the floor of the coating room (3). The work-applying electrostatic coating apparatus according to claim 1, wherein the apparatus is arranged so as to be able to advance and retreat in conjunction with the movement of (8).