JPH0353399B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a pretreatment device for electrodeposition coating.

(Prior art) Generally, the automotive painting process involves pre-treatment, undercoating,
It consists of four basic processes: intermediate coating and top coating.

Among these basic steps, the pretreatment step is carried out according to the flow sheet shown in FIG. 5, and its purpose is to
Completely removes oil adhering to the car body (hereinafter referred to as the object to be coated) transported from the body shop (degreasing treatment), and forms a chemically stable inorganic film on the surface of the steel plate (film conversion treatment) The purpose of this is to inactivate the surface of the steel plate, provide anti-rust properties, and improve the adhesion between the steel plate and the paint film. Here, in the degreasing treatment, an alkaline degreasing liquid containing sodium phosphate or the like is used, and in the film chemical conversion treatment, a chemical conversion liquid containing zinc phosphate or the like is used.

(Problem to be Solved by the Invention) In this pre-treatment process, the object to be coated is usually transported while being hung on a hanger, so the degreasing liquid and chemical liquid attached to the top of the hanger form the hanger. The degreasing liquid and chemical liquid remaining on the top of the hanger are scattered by the heat of the hot air stove, and the degreasing liquid and chemical liquid remaining on the top of the hanger are dispersed by the heat of the hot air oven. Adheres to the surface of the object being coated. When the next step, electrodeposition coating, is applied to the object in this state, there is a problem in that the adhered areas become lumpy, causing defects in the coating film, which has become a major problem that needs to be solved.

In view of the above problems, the present invention aims to prevent degreasing liquid and chemical conversion liquid from being brought into the drying oven.

(Means for Solving the Problems) As a means for solving the above problems, the present invention provides a pretreatment process for electrodeposition coating, a surface treatment process including a degreasing process, a film chemical conversion process, etc., and a drain drying process. In a pretreatment device in which processes are arranged in sequence to perform surface treatment on the object to be coated, wash it with water, and then dry it, the object to be coated is placed on a hanger consisting of multiple parts until it passes through the surface treatment step of the pretreatment step. At least in the film chemical conversion treatment step of the surface treatment process, the object to be coated is immersed together with a hanger in the treatment liquid, and the object to be coated is immersed in a drying oven in the draining and drying step. a second conveying device that conveys the object, and a transfer device that is provided between the first conveying device and the second conveying device, and that unloads the object to be coated from the hanger of the first conveying device and transfers it to the second conveying device. It is characterized by being equipped with a loading device.

(Function) In the present invention, in the above-mentioned means, that is, in the pretreatment step, the workpiece is drained and dried from the first conveyance device that hangs and conveys the object to be coated on a hanger composed of a plurality of parts until it passes through the surface treatment step. In the process, a degreasing liquid or a chemical solution is brought into the drying furnace by a means configured to unload and transfer the object to be coated from the hanger to a second conveying device that conveys the object to be coated within the drying oven. This has the effect of preventing

(Embodiment) A preferred embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

This pre-treatment device is a surface treatment device 1 that performs conventional degreasing treatment, film conversion treatment, and water washing treatment on a workpiece 3 (vehicle body) transported from a car body factory.
and a hot air drying oven 2 that performs draining and drying after surface treatment.

The surface treatment device 1 is attached with a first conveyor device 4 consisting of a hanger 5 on which the object to be coated 3 conveyed from the body shop is suspended, and an overhead conveyor 6 for moving the hanger 5 (a second conveyor device 4). (see figure). Reference numeral 7 is a guide rail. Reference numeral 29 is a device for hanging the object 3 to be coated on the hanger 5 of the first conveying device 4.

The hanger 5 is composed of a plurality of parts including a central support part 5a connected to the overhead conveyor 6 and hanging parts 5b, 5b rotatably supported by the central support part 5a.

On the other hand, the hot air drying oven 2 is attached with a second conveying device 8 consisting of a truck 9 on which the object to be coated 3 is placed and a floor conveyor 10 for moving the truck 9 (see FIG. 3).

Between the first conveying device 4 and the second conveying device 8 is a transfer device configured to transfer only the object 3 to be coated from the hanger 5 of the first conveying device 4 to the trolley 9 of the second conveying device 8. A loading device 11 is provided.

As shown in FIG. 4, the transfer device 11 includes an upper hanger transfer section 12 into which a portion of the first transfer device 4 is introduced, and a lower cart into which a portion of the second transfer device 8 is introduced. Transfer section 13 and the hanger transfer section 12
and lifting members 14, 14 that move up and down along the base frame 15 between the carriage transfer section 13 and the carriage transfer section 13.

The hanger transfer section 12 is provided with hanger opening/closing devices 16, 16 configured to open and close the hanging sections 5b, 5b of the hanger 5 in the left-right direction. The hanger opening/closing device 16 includes a cylinder 17
and the hanger hanging part 5 in conjunction with the cylinder 17.
b is constituted by an engaging piece 18 that opens as shown by the chain line. Reference numeral 19 denotes a hanger regulating device that regulates swinging when the hanger is opened and closed, and is composed of a cylinder 20 and a stopper 21 that is moved forward and backward by the cylinder 20.

The elevating member 14 moves up and down guided by the pillars 22 of the base frame 15, and has a support portion 14a at its inner end on which the object to be coated 3 is placed. The width between the support parts 14a, 14a of both the lifting members 14, 14 is made slightly larger than the width of the truck 9.

Further, both the elevating members 14, 14 are moved between the hanger transfer section 12 and the cart transfer section 13 by roller chains 24, 24 that move up and down as the rollers 23, 23 installed on the upper part of the support column 15 rotate. It is designed so that it can be raised and lowered. The rollers 23, 23 are driven by a motor 25 that can rotate in forward and reverse directions.
It is designed to be rotated synchronously by. Reference numeral 26 is a roller chain for synchronous rotation, and 27 is a counterweight.

Thus, this transfer device 11 operates as follows.

When it is confirmed by a limit switch or the like (not shown) that the workpiece 3 hung on the hanger 5 of the first transport device 4 has been transported to the hanger transfer section 12, the hanger opening/closing devices 16, 16 are opened. When activated, the hanger 5 is opened as shown by the chain line, and the object 3 to be coated is supported on the support portions 14a, 14a of the elevating members 14, 14. Next, when it is confirmed by a limit switch or the like (not shown) that the cart 9 of the second transport device 8 has been transferred to the cart transfer section 13, the motor 25 is driven to move the elevating members 14, 14 to the cart. It is lowered to the platform 13 and the object 3 to be coated is placed on the carriage 9 (as shown by the chain line in FIG. 4). Then, at the same time as the trolley 9 on which the object 3 to be coated is moved, the motor 25 is reversed to return the elevating members 14, 14 to the hanger transfer section 12, and the next object to be coated is moved by the first conveyance device 4. They are forced to wait until they are transported. In other words, only the object 3 to be coated that has been transported by the first transport device 4 is transferred to the second transport device 5.

The transfer device 11 is also installed on the exit side of the hot air drying oven 2, and transfers the object 3 from the second transfer device 8 to the third transfer device 28 (similar to the first transfer device) for the electrodeposition bath. It is used for transfer to a hanger type).

In the above configuration, in the pretreatment device of this embodiment, only the workpiece 3 transported by the first transport device 4 in the surface treatment process including degreasing treatment, film conversion treatment, and water washing treatment is transferred to the transfer device 4. At step 11, it is transferred to the second conveying device 8 and conveyed to the hot air drying oven 2, so that the degreasing liquid and chemical conversion liquid used in the surface treatment process are not carried into the hot air drying oven 2.

(Effects of the Invention) As described above, according to the present invention, in the surface treatment process, the first conveying device conveys the object to be coated by a hanger composed of a plurality of parts, and the first conveyor device that conveys the object to be coated in the drying oven. The second conveying device that conveys the object is constructed separately, and the object to be coated is unloaded from the hanger of the first conveying device and transferred to the second conveying device using a transfer device provided between the two. , the degreasing liquid and chemical liquid used in the surface treatment process are no longer brought into the drying oven, preventing the liquid from adhering to the object to be coated, and as a result, the occurrence of lumps during the next process of electrodeposition coating. It has the excellent effect of being able to prevent it from happening.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of a pretreatment device for electrodeposition coating according to an embodiment of the present invention, FIG. 2 is a front view of the first conveyance device in FIG. 1, and FIG. 3 is a second conveyance device in FIG. 1. FIG. 4 is a front view of the device, FIG. 4 is a front view of the transfer device in FIG. 1, and FIG. 5 is a flow sheet showing a general pretreatment process. 2...Drying oven, 3...To be coated, 4...First conveyance device, 5...Hanger, 8...Second conveyance device, 1
1...Transfer device.

Claims (1)

[Claims] 1 As a pre-treatment process for electrodeposition coating, a pre-treatment device that sequentially includes a degreasing process, a surface treatment process including film conversion treatment, etc., and a draining and drying process to treat the surface of the object to be coated, wash it with water, and then dry it. The object to be coated is hung on a hanger made up of a plurality of parts and transported until it passes through the surface treatment step of the pretreatment step, and at least the film conversion treatment step of the surface treatment step is carried out. A first conveying device that immerses the object to be coated together with the hanger in the liquid, a second conveying device that conveys the object to be coated in a drying oven in the draining and drying step, and between these first and second conveying devices. 1. A pretreatment device for electrodeposition coating, comprising a transfer device for unloading an object to be coated from a hanger of a first transfer device and transferring it to a second transfer device.