JPS60106979A - Rust preventive method of automotive body - Google Patents

Abstract

PURPOSE:To prevent rusting at the mating surface of steel sheets and to obtain safely and economically a rust preventive effect by sandwiching and uniting a sacrificial anode plate on both surfaces of which galvanizing films are formed into the mating surface of the steel sheets then painting the entire part of the automotive body. CONSTITUTION:A sacrificial anode 7 on both sides of which galvanizing films 8a, 8b are formed is sandwiched and united between >=2 sheets of steel plates constituting an automotive body, i.e., between a front panel 1 and a light side front fender 2 and a left side front fender 3 at both ends thereof. The films 8a, 8b are formed to 5-300mu thickness in this case. The entire part of the automotive body is painted, then if an electrolyte such as rain water, salt water or the like infiltrates the mating surface A between the anode 7 and the steel sheets 1, 2, 3, the steel sheets 1, 2, 3 act respectively as a cathode and the anode 7 acts as an anode, thereby forming a kind of local battery. The films 8a, 8b of the anode 7 are therefore corroded (eluted) preferentially to the steel sheets and rusting at the above-mentioned mating surface A is prevented.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a rust prevention method for an automatic Il (inner plate assembly 1 in which two or more steel plates constituting an individual body are combined with each other). It is.

[Prior art]

Conventionally, in the joining of two or more steel plates that make up an automatic intermediate body (1!1), rust prevention treatment such as painting has not been carried out, and rust has always been a problem. It has become. An example of this will be explained using the steel plate seam between the front fender and the front 1 balance panel shown in FIGS. 3 and 4.

That is, Fig. 3 is a perspective view of the front fender and front balance panel assembled, and the fourth
The figure is an enlarged sectional view taken along the line IV-IV of FIG. 3. Figures 3 and 4 show the front balance panel 11 and this front 1 balance panel l.
At both ends of the front fender, the right 2 and left 3 are assembled and integrated.

As shown in the enlarged sectional view of FIG. 4, the assembly is performed by forming flanges 2a and 1a on the front fender light 2 and the front balance panel l, which are bent inwardly to IJ'C. and its both flanges 2a
, la are formed with through holes (not shown) in opposing portions, respectively.

Furthermore, bolts 4 are inserted into the through holes on both pages, CJ3 is inserted, a nut → 5 is inserted on the front balance panel l side, and a ζ:1 nut 6 is tightened on the front fender f12 side. (J has a deviated structure and C.

In this state, a
Iil treatment, electrodeposition coating, etc. II! ! Painting, intermediate coating, and second coating are performed in sequence to form a coating film.

However, front 1 fender right and left 2.3
The steel plate alignment +4A' with the front balance panel 1 was not sufficiently degreased or chemically treated even after painting, and the steel plates came into contact with each other without forming a paint film, resulting in 1■ water being applied to this area. There is a problem that salt water etc. can enter and cause rust.

In order to solve the incompatibility as described in J-, the following rust prevention methods are currently being used.

The first rust prevention method is to apply a base coat such as electric paint to the front balance panel L and front fender right 2 and left 3 after they are assembled.
A method of sealing seam A by applying a PVC sol-based sealer.

In addition, the second rust prevention method is to apply electrodeposition coating, etc., without assembling the front balance panel 1, the front fender line 1-24, and the reflector 13 at the stage of assembling the vehicle body. A method of assembling the front balance panel l, front fender lights 2, and reflexes I and 3 using bolts 4 after base painting.

Furthermore, the third rust prevention method is the front balance panel 1
A method in which the entire structure is made of rust-proof steel plate such as galvanized steel plate.

However, in the first rust prevention method, the sealer hardens and ages due to vibrations during driving of the car and over time, causing cracks in the sealer, and then rainwater, salt water, etc. enter into the cracks. C: There is a problem that causes rust. In addition, in the second rust prevention method, in the degreasing, chemical conversion treatment process, and electrodeposition coating process, which is the base coating, either the right 2, left 3 or front balance panel l of the front fender is fixed with a strong jig. It is necessary to pass through the processing liquid in a floating state, and if the front balance panel 1 etc. falls from the jig during electrodeposition coating, it may cause an electrical short circuit and cause a "C accident".゛4
There is a dissonance. Furthermore, in the third prevention method (214), the entire front balance panel 1 is rust-proofed #I1.
It has to be formed with one slope, and there is a dissonance that costs "-51".

[Object 1 of the Invention] The present invention has been made to solve the problems described in [1]. By sandwiching and integrating the steel plates, rust is prevented from forming at the seam of the steel plates, and safety is ensured.
Further, it is an object of the present invention to provide a method for preventing rust of an automatic heavy body, which can economically obtain a rust-preventing effect.

[Structure of the invention]

1. In order to achieve the goal of 1, the method for preventing rust of an automatic car body according to the present invention is to prevent the rust of two or more sheets that constitute a car car break. A sacrificial anode plate with curved button plating film formed on both sides is sandwiched between the steel plates where l Ui are combined with each other, and l'jl jX! After the steel plate and sacrificial anode plate are integrated, the entire automatic weight body is painted.

Then C is formed on both ibj of the sacrificial anode plate! l! The thickness of the lead foil film on one surface of the sacrificial anode plate is suitably in the range of 5μ to 300μ, and the thickness of the film is 11. If the thickness is less than 5 μm, the galvanized film may peel off when the steel plate and the sacrificial anode plate are assembled and integrated, and the metal of the sacrificial anode plate may be exposed, resulting in non-compatibility that makes it impossible to improve rust prevention. There is. Further, if the thickness of the coating is 300 μm or more, there is a problem that the cost of coating for forming the galvanized coating on the sacrificial anode plate increases.

In addition, the reason why we limited it to sacrificial anode plates was to form a galvanized film on both sides at the seam of the steel plates.
If a metal that is less base than steel plates, such as magnesium, is inserted between the steel plates, sacrificial corrosion may occur over time, and the base metal may melt away, creating a gap between the steel plates.
As a result, a serious defect was caused in that the strength of the steel plate mating portion was reduced, so the sacrificial anode plate was limited to a sacrificial anode plate with galvanized coatings formed on both sides.

[Action of the invention]

In this automatic rust prevention method, a steel plate and a
An electrolyte such as mountain water or salt water is placed in the LJ at the joint with the π-containing anode plate.
When applied to a person, the local type is applied in the presence of a combined 1" electrolyte. ! The curved button plating film formed on the sacrificial anode plate becomes a sacrificial anode and is dissolved into the electrolytic solution, thereby preventing the occurrence of rust on the steel plates. That's right.

'C1 This defense! +! In the + method, the galvanized film continues to be dissolved and rust is prevented from forming on the steel plate.

〔Example〕

Hereinafter, embodiments of the present invention will be described based on the drawings.
Explain in detail.

Fig. 1 11 A perspective view of the state in which the rust prevention method according to the present invention is applied to the tMJlj seam of the front I and fender 7 ft balance panels.
FIG. 3 shows an enlarged cross-sectional view taken along the line.

[Configuration of Example J In Figures 1 and 2, -1 is a) 1J front balance panel, and both ends of this front balance panel 1 are provided with a left side front The fenders 3 and 3 are combined into one.

As shown in the enlarged sectional view of Fig. 2, the assembly is carried out using a flange 2 that bends inwardly between the light side front 1 Zenda 2 and the front balance panel 1.
a and la are formed, and n through holes (not shown) are formed in opposing portions of both flanges 2a and 1a, respectively.

Further, a sacrificial anode plate 7 formed in the same external shape as both flanges 2a and la is sandwiched between the steel plates of both flanges 2a and la, and a galvanized film and a , 8b are formed to have a thickness in the range of 5μ to 300μ. A through hole (not shown) is formed in this sacrificial anode plate 7 at a portion facing the through holes formed in both flanges 2a and la.

Furthermore, bolts 4 are inserted through both page through holes, and washers 5 are interposed in the front balance panel. Further, a nut 6 is screwed onto the light side front fender 2 side, and the light side front fender 2, the front balance panel l, and the galvanized coatings 8a, 8
The sacrificial anode plate 7 having b formed thereon is firmly fastened.

[Effect of the embodiment]

By taking the above technical measures, the following effects can be achieved. In other words, when electrolytic solution such as rainwater or salt water enters the steel plate seam A between the steel plate and the sacrificial anode plate, the electrolyte will be used to damage the front balance panel l and the right and left side front fenders 2.3 through the electrolyzer. The steel plate becomes the cathode and the sacrificial anode plate 7 becomes the anode, forming a kind of local battery.

Then, a small amount of water (HIO) in the electrolyte becomes H+.
and OH-, and the galvanized film 8 of the sacrificial anode plate 7
Positive metal ions pushed out from a and 8b and OH-
are combined and released as a metal oxide, and as a result, the galvanized films 8a and 8b of the sacrificial anode plate 7 corrode (
(dissolved).

On the other hand, the negative electrons generated from the sacrificial anode plate 7 move to the front balance panel l and the steel plates of the right and left front fenders 2.3 and are negatively charged.
It combines with moisture 11+ and 02 in the moisture on the surface of the steel plate to generate water.

In this way, the galvanized film 8a of the sacrificial anode plate 7,
8b is actively corroded (dissolved) preferentially to the steel plate, and rust is prevented from forming at the seam A of the steel plates of the front balance panel 1 and the front fender 2.3 on the right and left sides.

Although the sacrificial anode plate 7 in the present invention is attached by fixing it with bolts 4 and nuts 6 as a means, the present invention is not limited to this embodiment, and various attachment methods may be used. can do. For example, the sacrificial anode plate 7 is spot welded to one side of the steel plate in advance (method: one end of the sacrificial anode plate 7 is formed into a hook shape, the hook-shaped part is hooked and set to one of the steel plates, and then spot welded,
There are methods of fixing with bolts and nuts.

〔Effect of the invention〕

As explained above, in the rust prevention method for four automobiles according to the present invention, a sacrificial anode plate having curved lead plating films formed on both sides is sandwiched and integrated at the seam of two or more steel plates, and then, Since the entire four automobiles are painted, if electrolyte such as rainwater or salt water enters the joint between the steel plates, the galvanized film formed on the surface of the sacrificial anode plate will act as a sacrificial anode plate. Since it dissolves into the electrolyte, it has the effect of preventing rust from forming at the joints of the copper plates.

Furthermore, in the present invention, the generation of rust can be prevented by inserting a sacrificial anode plate with curved lead plating on both sides between the steel plates. This has the effect that the rusting process can be completed and work can be carried out safely in the degreasing, chemical conversion treatment process and the electrodeposition coating process which is the base coating.

In addition, the present invention not only eliminates the need for jigs in the degreasing, chemical conversion treatment, and electrodeposition coating processes, but also eliminates the need to apply seek at the seams of steel plates, thereby achieving an economical rust prevention effect. There is an effect that can be done.

[Brief explanation of drawings]

FIG. 1 shows the rust prevention method according to the present invention on a front fender and a front balance. It is a perspective view of a state in which + flannel is applied to steel plate assembly 1. FIG. 2 is an enlarged sectional view taken along the line ■--■ in FIG. 1, and FIG. 3 is a perspective view of the conventional front fender and front balance panel assembled. FIG. 4 is an enlarged sectional view taken along the line IV-ITJ in FIG. 3. 1--Front balance panel 1a--Flange 2--Light side front fender 7, a--
--- Flange 3 --- Left front fender 4 --- Bolt 5 --- Washer 6 --- Nut 7 --- Sacrificial anode plate 9 a, 8 b --- ---Zinc plating film Figure 1 Figure 2 Figure 4

Claims (1)

[Claims] Two or more ills constituting an automatic middle body
1. At the seams of the 11 boards that were put together, galvanized metal and skin F on both sides. A rust prevention method for an automatic L1th body, which includes inserting a sacrificial anode plate formed with a sacrificial anode plate, integrating the steel plate and the sacrificial anode plate, and then painting the entire body of the vehicle.