JPH0444620Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] This invention applies electricity to the object to be coated, which is placed on a hanger of a conveyor and immersed in an electrodeposition paint liquid in an electrodeposition bath, to form an electrodeposition coating film. The present invention relates to an electrodeposition coating device.

[Conventional technology]

Electrodeposition coating equipment that forms an electrodeposition coating film on the surface of the object to be coated slides a current collector installed on the hanger of a conveyor that transports the object to a current collector rail installed above the electrodeposition tank. In this way, electricity is applied to the object to be coated immersed in the electrodeposition coating liquid.

By the way, in automotive painting, it is required to strictly control the thickness of the electrodeposition coating within the range of 20 μm to 30 μm (±15%), but the thickness of the electrodeposition paint film in the electrodeposition tank is If the size of the car body to be dipped varies depending on the car model, and the coating area is uneven, accurate control of the film thickness becomes impossible.

In other words, since car painting lines transport a mixture of large and small car bodies, such as large cars and small cars, if the current is applied to match the film thickness of a large car with a large surface area, the paint film of a small car with a small surface area will be thicker. If this happens too much, you will end up wasting paint.

Furthermore, if the amount of electricity is kept constant, the film thickness cannot be changed depending on the type of vehicle such as a passenger car or a truck.

[The problem that the idea attempts to solve]

For this reason, in the past, a bypass rail was installed on the main conveyor rail, which transports the automobile body placed on the hanger and passes through the electrodeposition tank, and branched off from the middle of the rail to intersect with the rail again. The loaded hanger is suspended from the main conveyor rail and passed completely through the electrodeposition tank, and the hanger carrying the small car is transferred from the main conveyor rail to the bypass rail on the way through the electrodeposition tank, and the large car is transferred from the main conveyor rail to the bypass rail. A method has been proposed to change the amount of energization by opening the tank earlier than the previous one.
(Refer to Publication No. 125394), in this case, the provision of a bypass rail on the main conveyor rail becomes a large-scale construction, which increases the equipment cost of the conveyor, and the hanger carrying the object to be coated falls off when changing between the two rails. There was a risk that the painting line would stop.

In addition, a method has been proposed in which the conveyor rail has the same conventional structure and the effective area of the electrodes provided in the electrodeposition tank is changed depending on the type and size of the car (in 1987). −75466, JP-A-61-
(Refer to Publication No. 231199), in this case, the drive mechanism and control mechanism for changing the effective area of the electrode in the tank become extremely complicated.

There is also a method of changing the distance between the two electrodes by moving the electrode in the tank back and forth with respect to the object to be coated, which is the opposite electrode (see Utility Model Application Publication No. 60-75467), but in this case as well, There is a problem in that the drive mechanism for advancing and retracting the electrodes and its control mechanism are complicated and equipment costs increase.

Therefore, the present invention has a simple configuration that does not increase equipment costs, and has a simple operation that does not require complicated controls, making it possible to control film thickness according to the type and size of the object to be coated. This is considered a technical issue.

[Means to solve the problem]

In order to solve this problem, the present invention has a current collector installed on a hanger of a conveyor that slides into contact with a current collector rail, and is placed on the hanger and immersed in an electrodeposition paint liquid in an electrodeposition bath. In an electrodeposition coating device that forms an electrodeposited coating film on the surface of an object to be coated by applying electricity to the object, a plurality of tubes are used in which the amount of current applied varies depending on the type or size of the object to be coated. Electric rails are installed in parallel, and the hanger is provided with a current collector that selects and slides into contact with a current collecting rail that is suitable for the amount of current applied to the object to be coated from among the current collecting rails. shall be.

[Effect]

According to the present invention, the current collector provided on each hanger selects a specific current collecting rail that is suitable for the amount of current applied to the workpiece placed on the hanger from among a plurality of current collecting rails having different current amounts. By selectively coming into contact with the electrodeposition coating liquid, an electrodeposition coating film having a required thickness depending on the type of the object to be coated is formed on the surface of the object immersed in the electrodeposition coating liquid. Further, it is also possible to form an electrodeposited coating film of a constant thickness regardless of the size of the coated area of the object to be coated.

[Example] Hereinafter, an example of the present invention will be specifically described based on the drawings.

FIG. 1 is a front view showing an example of an electrodeposition coating apparatus according to the present invention, and FIG. 2 is a schematic side view thereof.

In this example, a conveyor rail 4 for suspending the hanger 3 of the conveyor 2 is installed along the upper side of the electrodeposition bath 1, and four current collecting rails R1, 4 are installed along the lower side of the conveyor rail ₄ . R ₂ , R ₃ and R ₄ are constructed in parallel.

Both of the current collecting rails R ₁ and R ₂ are used when energizing a large workpiece 5 with a large painting area, but one current collecting rail R ₁ is connected to a power source 6 with a high voltage, The other current collection rail R ₂ is connected to a power source 7 with a low conducting voltage.

The current collector rails R ₃ and R ₄ arranged below the current collector rails R 1 and R ₂ are each selected to have _a shorter length than the current collector rails R ₁ and R ₂ , so that the coating area is smaller. Used when applying electricity to small objects to be painted, one current collector rail R ₃ is connected to the same power source 6 as the current collector rail R ₁ placed directly above it, and the other current collector rail R ₄ is connected to the same power source 6 as the current collector rail R 1 placed directly above it. It is connected to the same power supply 7 as the current collection rail R ₂ arranged in the.

In addition, the hanger 3 in FIG.
The upper end of the current collector rail R ₁ is placed at the same height on the left and right sides of the part.
A current collector 8 that can be slidably contacted with both R2 and _R2 is provided. In other words, the current collector 8 is configured to be able to swing 180 degrees to the left and right sides of the hanger 3, and is configured to be able to selectively come into sliding contact with either the current collecting rail _R1 or _R2 . There is.

If the large object 5 to be coated placed on the hanger 3 is the body of a passenger car for which a thick electrodeposited coating is desired, the current is collected on the collector rail R ₁ with a high voltage that matches the amount of current applied to the body. The electron 8 is brought into sliding contact, and
If the truck body does not require a thin coating,
The current collector 8 is brought into sliding contact with a current collecting rail R ₂ having a low applied voltage that matches the amount of current applied to the body.

Thereby, even if the same large-sized object 5 is to be coated, it is possible to form electrodeposited coating films having different thicknesses depending on the type of the object.

Although not shown in the drawing, the hanger on which the small-sized workpiece is placed is equipped with a current collector that slides into selected short current collection rails R ₃ and R ₄ , so that the workpiece placed on the hanger is small. If it is a passenger car body,
A current collection rail with a high voltage connected to the same power source 6 as the current collection rail R ₁ that carries current to the body of a large passenger car.
By sliding the current collector into contact with R ₃ and shortening the current application time by a certain period of time compared to the case of large passenger cars, it is possible to form electrodeposited coatings of the same thickness on the bodies of passenger cars of different sizes.

In addition, if the object to be coated placed on the hanger is the body of a small truck, the current collecting rail R ₄ with a low voltage connected to the same power source 7 as the current collecting rail R ₂ that energizes the body of a large truck is connected. By bringing the current collector into sliding contact and shortening the current application time by a certain period of time compared to the case of large trucks, it is possible to form electrodeposited coatings of the same thickness on the bodies of trucks of different sizes.

In other words, if there are differences in the size of the same type of workpiece, the amount of current applied can be changed by selecting the length of the current collection rail that the current collector slides on, depending on the difference.
Electrodeposition coatings of the same thickness can be formed on objects with different coating areas.

[Effect of idea]

As described above, the electrodeposition coating device according to the present invention has a plurality of current collecting rails installed in parallel, each having a different amount of current applied depending on the type and size of the object to be coated, and a rail on which the object to be coated is placed. The extremely simple mechanism of simply installing a current collector on the hanger of the conveyor by selecting a current collector rail suitable for the amount of current applied to the object from among the current collecting rails and slidingly contacting the current collector rail allows the current collector to be coated without the need for complicated controls. This has a very good effect of being able to control the film thickness according to the type and size of the object to be coated.

[Brief explanation of drawings]

FIG. 1 is a front view showing an example of an electrodeposition coating apparatus according to the present invention, and FIG. 2 is a schematic side view thereof. Explanation of symbols, 1...electrodeposition tank, 2...conveyor,
3... Hanger, 4... Conveyor rail, 5... To be painted, 8... Current collector, _R1 to _R4 ... Current collector rail.

Claims (1)

[Scope of utility model registration request] The current collector provided on the hanger 3 of the conveyor 2 is brought into sliding contact with the current collection rail, and the object 5 to be coated is placed on the hanger 3 and immersed in the electrodeposition paint liquid in the electrodeposition tank 1.
In an electrodeposition coating device that forms an electrodeposited coating film on the surface of the object 5 to be coated by applying electricity to the object 5, a plurality of current collectors are used to apply electricity to different amounts of electricity depending on the type or size of the object 5 to be coated. Rails R ₁ to _{R 4} are installed in parallel, and the hanger 3 is provided with the current collector rail.
An electrodeposition coating apparatus characterized by being provided with a current collector 8 that selects and slides into contact with a current collecting rail suitable for the amount of current applied to the object 5 to be coated from among R ₁ to R ₄ .