JPH03224651A - Electrostatic coating equipment for conductive coating material and current collecting rail used therefor - Google Patents

Abstract

PURPOSE:To enable electrostatic coating with the simple modification of the existing equipment without applying insulation and safety measures to the coating material supply line of a coating machine by providing an insulating conveyor for conveying a body to be coated in an electrically insulated state and a current collecting rail for impressing a high voltage on the body being conveyed. CONSTITUTION:A high voltage is impressed on an automobile body W placed on an insulating truck 9 on an insulating conveyor 3 from a current collecting rail 11 in sliding contact with a contact 15 provided to the truck 9. The contact 16 is firstly brought into contact with the rail 11 at a low-voltage part c and transferred to a high-resistance part b from the low- voltage part c, hence the voltage to be impressed on the body W is gradually increased, and a spark discharge is not generated. The contact 15 is then brought into sliding contact with a high-voltage part a of the rail 11, a specified high voltage is impressed on the body W on the truck 9 being conveyed in a coating zone, and the coating particles sprayed from the coating machines 18R and 18L of side reciprocating devices 12R and 12L and from the coating machine 17 of a top reciprocating coating machine 13 are sucked and attracted on the surface of the body W by the action of an electric field generated between the particles and the body W.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to the use of conductive paints for electrostatically applying water-based paints, slurry paints, metallic paints, etc. to objects to be coated that are continuously conveyed by a conveyor. Regarding electrostatic coating equipment.

[Conventional technology]

Water-based paints have the disadvantage that the gloss of the paint film is inferior to that of insulating resin paints that use organic solvents.

In addition, when spraying conductive paint such as water-based paint with an electrostatic sprayer that applies high voltage, insulation measures must be taken on the paint supply system to prevent the high voltage applied to the sprayer from leaking. Because of the necessity (see JP-A-55-114366 and JP-A-56-141869), multi-color coating equipment for automobile painting that changes colors of paint from dozens of colors is used for each paint color. However, there was the trouble of having to insulate the paint supply piping and paint tank, respectively.

For this reason, in automotive painting, where low-cost, high-quality painting is required, the use of water-based paints, which significantly increase the cost of insulation measures and have poor gloss, has been postponed, and electrostatic painting using insulating resin paints has been abandoned. It occupies the mainstream.

[Problem to be solved by the invention]

However, in recent years, there has been a growing global environmental conservation movement, and calls have been made to regulate the use of organic solvents that generate polluting substances such as hydrocarbons, in addition to fluorocarbon gases.

Painting equipment consumes a large amount of this organic solvent.

In view of these circumstances, there is also a movement in the coating industry to reconsider painting with water-based paints that do not require harmful organic solvents such as thinner, and to develop water-based paints with good gloss.

However, even if the gloss of water-based paints improves, the use of non-polluting water-based paints cannot be promoted unless the trouble of providing insulation for the paint supply system of multi-color coating equipment is resolved.

In particular, when using conductive paints such as water-based paints, it is necessary not only to insulate the paint supply system, but also to protect the paint supply piping and paint tank from electrical shock by approaching the insulated paint supply system. It has been extremely difficult to promote the conversion from insulating resin paints to water-based paints because it is necessary to take safety measures such as enclosing the paints in a chamber, etc., and requires a large amount of equipment costs.

Therefore, the main technical problem of the present invention is to eliminate the need for troublesome insulation and safety measures in the paint supply system of the paint sprayer when electrostatically painting conductive paints such as water-based paints. There is.

Furthermore, in order to promote painting with non-polluting water-based paints, the present invention utilizes existing electrostatic painting equipment that performs painting with insulating resin paints and simply makes modifications to it. Another challenge is to enable electrostatic painting of water-based paints.

[Means to solve the problem]

In order to solve this problem, the electrostatic coating equipment according to the present invention electrically transfers the workpiece transferred from the line converter along the coating zone where an automatic coating device connected to ground potential is installed. It is characterized by being provided with an insulated conveyor that conveys in the L4@edge state and a current collection rail that applies a high voltage to the object to be coated that is being conveyed by the insulated conveyor.

[Operation] According to the present invention, the object to be coated that is being conveyed by the line conveyor is transferred to the insulated conveyor and is conveyed in an electrically insulated state along the coating zone where the automatic coating device is installed. During transportation, a high voltage is applied from the current collector rail, and an electrostatic field is formed between the automatic coating device and the automatic coating device connected to ground potential, and due to the action of the electric field, the automatic coating device Paint particles sprayed from the tank are sucked and adsorbed.

In this way, even when a conductive paint such as a water-based paint is supplied to an automatic painting apparatus, there is no need to take troublesome insulation measures for the paint supply system.

In addition, conventional electrostatic painting equipment can be used as is by simply connecting the automatic painting equipment to ground potential and modifying it by installing an insulated conveyor and current collection rail along the painting zone where the painting equipment is installed. , equipment costs are not high.

Furthermore, since the object to be coated, which is conveyed by the line conveyor, is transferred to an insulated conveyor and electrostatically coated while being conveyed through the coating zone, the coating productivity does not decrease.

Therefore, it is possible to promote the transition from electrostatic coating using insulating resin paint to electrostatic coating using non-polluting water-based paint.

〔Example〕

Embodiments of the present invention will be specifically described below based on the drawings.

FIG. 1 is a front view showing an example of electrostatic coating equipment according to the present invention, FIG. 2 is a view thereof in the direction of arrow A, FIG. 3 is a view in direction of arrow B, and FIG. 4 is a view in direction of arrow C.

In this example, an insulating film is installed along and parallel to a line conveyor 2 that conveys an automobile body W to be coated into a tunnel-shaped painting booth 1, and conveys the automobile body W in an electrically insulated state. A conveyor 3 is installed, and a carry-in lifter 4 for transferring a car body W transported by the line conveyor 2 onto the insulated conveyor 3 is provided on the carry-in side and a carry-out side of the insulated conveyor 3, respectively, and a car carried by the insulated conveyor 3. A carry-out lifter 5 is provided for transferring the body W onto the line conveyor 2 again.

The insulated conveyor 3 has an endless chain 8 hooked in parallel between sprockets 7 and 7 provided at both front and rear ends of a tunnel-shaped insulated stand 6 formed to straddle the line conveyor 2 from side to side, and attached to the chain 8 at predetermined intervals. The automobile body W is placed on the insulated carts 9.9-- and pulled in the same direction as the conveyance direction of the line conveyor 2.

The insulated cart 9 that has arrived at the discharge side of the insulated conveyor 3 is reversed in the opposite direction to the conveying direction of the line conveyor 2, enters the inside of the tunnel-shaped insulated pedestal 6, and moves inside the pedestal 6 into the line compuff 20 cart. 10, and return to the insulating conveyor 3's carry-in side.

Further, a current collecting rail 11 is installed on the insulating frame 6 along the insulating conveyor 3 to apply a high voltage to the automobile body W being conveyed by the conveyor 3.

20 The current collecting rail 11 has a high voltage section a located along the coating zone of the side reciprocating coating devices 12R, 12L and the top reciprocating coating device 13 installed along the insulated conveyor 3, and both ends of the high voltage section a. A high voltage of about 80 to 120 KV DC is applied to the high voltage part a, and each high resistance part , and each low voltage section C is connected to the ground potential.

Further, the side reciprocating coating devices 12R, 12L and the top reciprocating coating device 13 are installed on pedestals 14R, 14L provided on both left and right sides with the insulating pedestal 6 in between, and are connected to the ground potential.

Each insulated cart 9 of the insulated conveyor 3 is provided with a contact 15 that slides into contact with the current collection rail 11, and a high voltage is applied to the automobile body W on the insulated cart 9 via the contact 15. There is.

The top reciprocating coating device 13 includes coating machines 17, 17, etc. attached to an elevating frame 16 disposed perpendicular to the conveyance path of the insulated conveyor 3, as shown in the view from arrow A in FIG. The elevating frame 16 is tracked along the conveyance path of the insulated conveyor 3 and raised and lowered to automatically paint the front, upper and rear surfaces of the automobile body W.

In addition, the side reciprocating coating devices 12R and 12L are
As shown in the view along arrow B in the figure, the painting machines 18R and 18L are moved up and down to automatically paint the left and right side surfaces of the automobile body W.

Next, the carry-in lifter 4 and the carry-out lifter 5 reciprocate with a predetermined stroke 2 on a rail 19 laid in parallel along the line conveyor 2, as shown in the view of arrow C in FIG. The automobile body W placed on the trolley 10 of the line conveyor 2 or the insulated trolley 9 of the insulated conveyor 3 is lifted by a telescopic fork 20 and transported in the transport direction of the line conveyor 2 at a higher speed than the transport speed. ing.

The automobile body W, which has been carried into the painting booth 1 on the trolley 10 of the line conveyor 2, is lifted by the fork 20 of the carry-in lifter 4 and transferred to the insulating conveyor 3.
The insulated cart 9 of the insulated conveyor 3
It can be transferred to.

Then, on the automobile body W placed on the insulated trolley 9,
A high voltage is applied from the current collection rail 11 on which the contactor 15 provided on the trolley 9 slides.

At this time, since the contactor 15 first contacts the current collection rail 11 at the low voltage section C connected to the ground potential, there is no risk of spark discharge occurring at the time of this contact.

Next, the contact 15 that has moved from the low voltage section C to the high resistance section
approaches the high-voltage part a while slidingly contacting the high-resistance part and gradually increases the voltage applied to the automobile body W placed on the insulated trolley 9, so there is no spark when moving to the high-voltage part a. There is no need to worry about electrical discharge.

If the length of the high resistance part is selected to be about 1 m, it is possible to reliably prevent high voltage leakage from high voltage part A to low voltage part C, and at the same time, it is possible to boost the voltage without causing spark discharge. can be done.

Then, when the contactor 15 comes into sliding contact with the high voltage part a of the current collecting rail 11 and a predetermined high voltage is applied to the automobile body W which is carried through the coating zone on the insulated trolley 9, the side reciprocating coating device 12R , 12L paint particles 18R, 18L and the paint particles sprayed from the paint sprayer 17 of the top reciprocating coating device 13 are attracted and adsorbed onto the surface of the car body W by the action of the electric field formed between the paint particles and the car body W. be done.

The automobile body W, which has been electrostatically coated in this way, is lifted from the insulating cart 9 by the fork 20 of the unloading conveyor 5 waiting on the unloading side of the insulating conveyor 3, and is moved in the conveying direction at a higher speed than the conveying speed of the line conveyor 2. It is transported and transferred again to the empty cart 10 of the line conveyor 2 that has passed through the inside of the tunnel-shaped insulating frame 6.

In this way, even when supplying conductive paint such as water-based paint to the coating devices 12R, 12L, and 13, it is possible to take troublesome insulation measures for the paint supply system or surround the insulated paint supply system with a chamber. There is no need to take safety measures such as

In addition, existing painting equipment that performs electrostatic painting using insulating resin paint can be used as is, and by simply modifying the equipment by installing an insulated conveyor 3 and a lifter 4.5, electrostatic painting using water-based paint can be performed. Since electrical painting is possible, equipment costs will not increase.

Furthermore, the objects to be coated, such as automobile bodies W, are transferred to the line conveyor 2.
Since the paint can be transferred between the paint and the insulated conveyor 3 and painted while being conveyed continuously without interruption, there is no reduction in painting productivity.

Therefore, it is possible to promote the transition from electrostatic coating using insulating resin paint to electrostatic coating using non-polluting water-based paint.

Note that the lifters 4 and 5 move the automobile body W to the fork 20.
Not limited to models that can be lifted up to 1 meter with
As shown in the figure and FIG. 6, a large magic hand 21
It may also be something that is lifted up and transported.

That is, FIG. 5 is a front view showing a modified example of the beam lid 4.5, and FIG. 6 is a side view thereof. Predetermined stroke along 22! A magic hand 21 that travels back and forth is suspended, and the magic hand 2
1, the vehicle bodies W arriving at the insulating conveyor 3 are grabbed and transported.

Further, in the embodiment described above, the lids 4 and 5 are provided on the insulating conveyor 3 on the carry-in side and the carry-out side, but the lids 4 and 5 are provided on the carry-in side and the carry-out side of the insulated conveyor 3 to lift only the car body W and travel back and forth with a predetermined stroke. , as shown in FIG.
A lifter conveyor 30 lifts the automobile body W placed on the carriage 10 at a fixed position and transfers it to the insulated conveyor 3, and a lifter conveyor 30 lifts the automobile body W placed on the carriage 10 at a fixed position and transfers it to the insulated conveyor 3. Trolley 10
A lifter conveyor 31 may be provided for transferring the entire line conveyor 2 to the line conveyor 2 again.

That is, FIG. 7 is a front view showing another embodiment of the present invention;
FIG. 8 is a view taken along arrow D, and on the carry-in side of the insulated conveyor 3, the car body W, which is carried on the trolley lO of the line conveyor 2, is lifted up together with the trolley lO, and the insulated conveyor 3 A lid conveyor 30 is provided on the insulated rails 32R, 32L, and on the discharge side of the insulated conveyor 3, the cart 10 that has traveled on the insulated rails 32R, 32L and passed through the coating zone is transferred again to the line conveyor 2. The lid conveyor 31 is filled with FEtLt.

Each lifter conveyor 30.31 has a pair of left and right rails 33 for running the cart 10, and a pair of front and rear sprockets 1-3.
4. The hydraulic cylinder 3
It is designed to be raised and lowered by 9.39.

In addition, 40.40 is a gas-filled cylinder provided to supplementally support the load of the pedestal 38, reduce the load on the hydraulic cylinder 39.39, and allow the pedestal 38 to be smoothly raised and lowered by the cylinder without impact. .

In addition, the insulated conveyor 3 has a trolley 1 that is transferred onto insulated rails 32R and 32L provided on the left and right insulated stands 6°6.
A contactor 4 that slides on the current collecting rail 11 and applies a high voltage to the automobile body W on the trolley 10 is attached to the insulated dog 41 that pulls the motor vehicle 0.
2 is installed.

Next, FIG. 9 is a front view showing still another embodiment of the present invention,
FIG. 10 is a view in the direction of arrow E.

The insulating conveyor 3 shown in this example is a belt conveyor in which insulating bells 52R and 52L made of rubber belts, etc. are hung in parallel between sprockets 50 and 51, which are provided in pairs at the front and rear. and a guide slope S for receiving the car body W placed on the trolley IO of the line conveyor 2 from the trolley 10, respectively, on the unloading side.
1, and the automobile body W that has passed through the coating zone where coating devices 12L (12R) and 13 are installed, is transferred to an insulating conveyor 3.
A guide slope S2 is formed on the trolley 10 of the line conveyor 2 that passes between the insulating frames 6 and 6 to transfer the line again.

In addition, each insulating pedestal 6 has a high voltage part a, a high resistance part b, and
is supported by insulators 53, 53...

The belts 52R and 52L are formed of synthetic rubber belts containing a predetermined ratio of conductive material such as carbon so as to exhibit high resistance in the longitudinal direction and low resistance in the thickness direction. The current collection rail 1 is passed through the rubber belt.
1, a high voltage is applied directly to the automobile body W.

〔Effect of the invention〕

As described above, according to the present invention, even when performing electrostatic coating with conductive paint such as water-based paint, insulation and safety measures, which are troublesome and increase equipment costs, are required for the paint supply system of automatic painting equipment. This has the effect that there is no need to lecture.

In addition, in order to eliminate the need for insulation and safety measures, we have installed an insulated conveyor that transports the object to be coated in an electrically insulated state along the painting zone where the automatic painting equipment is installed, and a Since it is sufficient to install a current collector rail that applies high voltage to the object to be coated, existing electrostatic coating equipment can be used as is and only modifications can be made to it, which has the excellent effect of not increasing equipment costs. be.

Furthermore, there is also the excellent effect that coating productivity does not decrease.

Therefore, the present invention can promote a transition from electrostatic coating using insulating resin paint to electrostatic coating using non-polluting water-based paint, and is extremely useful.

[Brief explanation of drawings]

Fig. 1 is a front view showing an example of electrostatic coating equipment according to the present invention, Fig. 2 is a view in the direction of the A arrow, Fig. 3 is a view in the direction of the B arrow, Fig. 4 is a view in the direction of the C arrow, and Fig. 5 is the beam. Front view showing a modified example of the lid, No. 6
7 is a front view showing another embodiment of the present invention, FIG. 8 is a view taken along arrow D, and FIG. 9 is a front view showing still another embodiment of the present invention. FIG. 10 is a view in the direction of arrow E. Explanation of symbols W-・Car body (object to be coated), 2- Line conveyor, 3...-Insulated conveyor, 4-・
Carrying in lifter, 5-- Carrying out lifter, 11-- Current collection rail, a-- High voltage section, b- High resistance section, C... Low voltage section, 1
2R, 12L...Side reciprocating coating device, 13-
Top reciprocating coating equipment, 30.31--Lifter conveyor, s,, s,--Guiding slope.

Claims (1)

[Scope of Claims] [1] The object to be coated (W) transferred from the line conveyor (2) is transferred to an automatic coating device (12R) connected to the ground potential.
), (12L), and (13) are conveyed along the painting zone in an electrically insulated state;
An electrostatic coating equipment for conductive paint, characterized in that it is provided with a current collection rail (11) that applies a high voltage to the object (W) to be coated that is being transported by the insulated conveyor (3). [2] The insulated conveyor (3) is a line conveyor (2)
) is installed in parallel above the insulated conveyor (
The work to be coated (W) placed on the trolley (10) of the line conveyor (2) is placed on the loading and unloading sides of 3).
A carry-in lifter (4) lifts the object from the insulated conveyor (3) and transfers it to the insulated cart (9) of the insulated conveyor (3). 2) The electrostatic coating equipment according to claim 1, further comprising a carry-out lifter (5) for transferring onto the trolley (10) of item 2). [3] The object to be coated (W) placed on the trolley (10) of the line conveyor (2) is lifted up along with the trolley (10) on the insulating conveyor (3) on the insulating conveyor (3) and the insulating conveyor (3). ), and the object to be coated (W) that has passed through the painting zone on the trolley (10) of the line conveyor (2) transported by the insulated conveyor (3) is transferred to the trolley ( 10) and the line conveyor (2) again.
2. The electrostatic coating equipment according to claim 1, further comprising a lifter conveyor (31) for transfer to a conveyor (31). [4] The insulated conveyor (3) carries the objects to be coated (W) placed on the trolleys (10) of the line conveyor (2) from above the trolleys (10) at both ends of the carry-in side and the carry-out side, respectively. The receiving guide slope (S,) and the workpiece (W) that has passed through the coating zone are transferred again to the carriage (1) of the line conveyor (2).
0) The electrostatic coating equipment according to claim 1, which is a belt conveyor having a guide slope (S_2) formed thereon. [5] A high-voltage part (a) that applies a predetermined high voltage to the object (W) being conveyed by the insulated conveyor (3), and a high-resistance part ( A current collection rail comprising: (b) a low voltage section (c) connected to the current collector rail via a low voltage section (c).