JPS6245631A - Plasma treatment apparatus - Google Patents

Abstract

PURPOSE:To obtain inexpensively the titled apparatus excellent in corrosion resistance, by using a material which is inexpensive and has a good workability as a base material for the inside wall of a holding chamber, hungers, etc., and forming an oxidation-inhibiting film on the surface of the base material. CONSTITUTION:A rotary unit 11 provided in a holding chamber 1 having an inside wall made of zinc phosphate-coated carbon steel having a film 8a comprising a thermosetting acrylic resin paint and a frame 12 are slidden toward an operator's side and bumpers B are mounted on the predetermined positions of hungers composed of a supporting piece 17, hunging rods 18a, 18b, etc., and made of carbon steel on which a thin film layer of nickel oxide is formed. the unit 11 is returned to the chamber 1, and the pressure in the chamber 1 is decreased by adjusting a valve 2a in a vent 2 and supporting discs 15a and 15b are rotated by actuating a drive motor. Along with the rotation of discs 15a and 15b, bumpers B in the unit 11 are rotated. A plasma gas supplied from a plasma generator is injected through a supply pipe 4 and an injection pipe 3 made of a chromium-coated carbon steel and bumpers B are plasma-treated.

Description

[Detailed Description of the Invention] Purpose of the Invention (Industrial Field of Application) The present invention provides a method for placing bumpers and other synthetic resin molded products on a plurality of hangers in a storage chamber, and by subjecting the surfaces of the bumpers and other synthetic resin molded products to plasma treatment. The present invention relates to a plasma processing apparatus that improves the adhesion of paint and the like, and more specifically to a plasma processing apparatus that is coated to prevent oxidation caused by plasma gas.

(Conventional technology) Polyolefin thermoplastic resins such as polyethylene (PE) and polypropylene (PP) and various thermosetting resins have poor adhesion to paints and adhesives, and even when these are applied, the paint film may peel off. Various pretreatment methods have been adopted because of their ease of use, but in recent years, plasma treatment methods have come into widespread use in which the surface of synthetic resin substrates is modified by electric discharge treatment under reduced pressure.

An example of an apparatus for carrying out the above-mentioned plasma treatment is the apparatus shown in Japanese Patent Application No. 58-236546 previously filed by the applicant of the present invention.

(Problem to be Solved by the Invention) However, in the above device, the entire containment chamber becomes an extremely activated atmosphere due to the oxygen plasma gas injected from the plasma injection tube. Stainless steel, which has excellent corrosion resistance, is used as the base material for the components.

Since steel and stainless steel have poor workability and are expensive, there is a problem in that the production cost of plasma equipment for processing large molded products such as bumpers is high.

The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to provide a plasma processing apparatus that uses a base material that is inexpensive and has good workability, and has an excellent anti-oxidation function.

Structure of the Invention (Means for Solving the Problems) That is, the present invention includes a storage chamber for accommodating objects to be painted such as synthetic resin bumpers, and a system that is installed on the wall of the storage chamber and injects plasma gas into the storage chamber. In a plasma processing apparatus equipped with a plasma injection tube that depressurizes the storage chamber, an exhaust port that reduces the pressure in the storage chamber, and a plurality of hangers on which objects to be coated are placed, at least the surface of the hanger base material is coated, wet-plated or dry-plated. The above-mentioned problems have been solved by employing a plasma processing apparatus characterized by forming an oxidation-preventing film by plating (vapor deposition, sputtering, ion blating, etc.).

(Function) Inexpensive and easily processable materials are used for each base material such as the inner wall of the storage chamber, the plasma injection tube, and the hanger that constitute the plasma processing apparatus, especially the base material of the hanger that receives a large amount of plasma irradiation. By forming an oxidation-preventing coating on the surface by painting, wet plating, or dry plating, it is possible to obtain an inexpensive device with excellent corrosion resistance.

(Example) Hereinafter, an example in which the present invention is embodied in an apparatus for plasma-treating the surface of a vehicle bumper will be described with reference to FIGS. 1 to 7.

First, as shown in FIG. 1, the storage chamber 1 of this embodiment is formed into a hollow cylindrical shape, and a door (not shown) is provided on the front wall of the storage chamber 1. It has become.

The inner wall material of the containment chamber 1 is a plate material made by pressing carbon steel, and after being subjected to a zinc phosphate coating treatment, a coating film 8a made of thermosetting acrylic resin paint is formed, and the coating film 8a is formed by irradiation with oxygen plasma gas. Corrosion of the base material is prevented.

Further, in the center of the right side wall of the storage chamber 1, there is provided an exhaust port 2 on which a coating film 8a made of thermosetting acrylic resin paint is formed. The air pressure can be adjusted to . Furthermore, this exhaust port 2 is connected to a suction pump (not shown), so that the inside of the storage chamber 1 can be reduced to a desired atmospheric pressure.

Next, near the lower part of the exhaust port 2 on the inner wall of the storage chamber 1, a plasma injection tube 3 made of carbon steel and having a chrome coating 8b formed by plating on its surface is arranged. Further, the plasma injection tube 3 is connected to a plasma generation device (not shown) via a variable tube 4, and is configured to inject oxygen plasma gas supplied from the device into the storage chamber 1.

Furthermore, as shown in FIG. 3, a large number of injection ports 5 are formed in this plasma injection tube 3.

In addition, the arrangement interval and the inner diameter of these injection ports 5 gradually increase from the center to both ends of the plasma injection tube 3.
In addition, the opening 5a is tilted forward at a predetermined angle θ (30 degrees in this embodiment) with respect to the vertical plane S, and the opening is tilted backward at a predetermined angle θ2 (30 degrees in this embodiment). 5
b are arranged alternately.

Next, as shown in FIGS. 1 and 2, a rotation device 11 is housed in the storage chamber 1 on a base 10 at the bottom thereof. This rotating device 11 is supported by a rectangular frame 12 and a pair of pillars 13a and 13b facing each other on both sides thereof, and is roughly constructed as follows.

That is, a rotating shaft 14 is provided between the upper ends of both branches 13a and 13b, and a chain wheel 2 is provided at the front end of this rotating shaft 14.
1a are inserted into each.

Furthermore, a chain wheel 21b that rotates around a uniaxial cotton and a transmission gear 23 are provided on the frame 12, and a drive gear 25 that is rotationally driven by a drive motor (not shown) is meshed with the transmission gear 23. . Furthermore, a chain 24 is hung between the chain wheels 21a and 21b, and as the drive gear 25 rotates, the rotating shaft 14 is rotated through the transmission gear 23, the chain wheel 21b, the chain wheel 24, and the chain wheel 21a. It is designed to be rotated.

The base 10, the frame 12, the columns 13a, 13b, and the rotating shaft 14 are all made of carbon steel, and a coating film made of the thermosetting acrylic resin paint is formed on their surfaces.

Next, at both ends of this rotating shaft 14, a pair of carbon steel support disks 15a, 15a and 15a, each having a coating film of the paint formed on the surface thereof, is provided.
5b are fixed to be rotatable together, and furthermore, between these support disks 15a and 15b, hangers 16 on which synthetic resin bumpers B such as polypropylene or polyurethane are placed are provided at predetermined angular intervals. It is being

As shown in FIG. 7, each hanger 16 includes a pair of support pieces 17 formed by bending a plate material, a pair of installation rods 18a and 18b installed in parallel on the lower surface of the support pieces 17, and a pair of installation rods 18a and 18b installed in parallel on the lower surface of the support pieces 17. It is composed of a connecting rod 19 that connects the rods 18a and 18b, and a net 20 that supports the end of the bumper B.

In addition, the hanger 16, the support piece 17, the erection rod 18a,
18b, the connecting rod 19, and the net 20 are all made of carbon steel, and a thin film layer of nickel oxide is formed on their surfaces by high-frequency ion blasting to prevent oxidation.

In addition, since each hanger 16 is relatively rotatably attached to both support disks 15a, 15b via metal fittings 22 at the two end positions of both support pieces 17, the rotating shaft 14, that is, support disks 15a, 15b It is designed to remain horizontal at all times, both at rest and when rotating.

Next, a process for processing the bumper B made of polypropylene using the plasma processing apparatus of this embodiment having the above-mentioned configuration will be described.

First, the door of the storage chamber 1 is opened, the rotation device 11 housed in the center thereof is slid forward together with the frame 12, and the plasma-treated Leham bar B is placed at a predetermined position on each hanger 16. Next, the rotating device 11
The pressure is reduced to the center of the storage chamber 1. When the pressure inside the storage chamber 11 is reduced to a predetermined pressure, the valve 2a is closed and the drive motor is activated to rotate the support disks 15a and 15b. At this time, each hanger 16 on which the bumper B is placed has both support disks 15a at its upper end position.

15b so that they can rotate relative to each other,
Bumper B holds both support disks 15a while maintaining its horizontal state.
, 15b. On the other hand, at the same time as the rotating device 11 is started, the plasma generating device is activated, and plasma gas supplied therefrom is injected into the storage chamber 1 from each injection port 5 of the plasma injection tube 3 via the introduction pipe 4.

At this time, the valve 2a provided at the exhaust port 2 is completely opened to prevent atmospheric pressure build-up due to the injection of plasma gas and to keep the inside of the storage chamber 1 at a predetermined pressure at all times.

Various coatings for preventing oxidation are formed on the inner wall of the storage chamber 1 and the surface of the main parts of the rotating device 11 of the plasma processing apparatus, so that even during long-term use, the base material (carbon steel) remains intact. Corrosion can be prevented. Furthermore, since the base material is cheaper and easier to work with than conventional plasma processing equipment using stainless steel, the manufacturing cost of the equipment is extremely low.

Note that the present invention is not limited to the above embodiments,
Detailed specifications can be changed as appropriate without departing from the gist. For example, instead of thermosetting acrylic resin, various paints with good corrosion resistance such as amino alkyd, acrylic modified alkyd, epoxy, and urethane paints may be used. It is also possible to use nickel and other various metals.

(2) A film made of various metals or metal oxides having good corrosion resistance may be formed using not only the high-frequency ion blasting method but also various dry plating methods such as sputtering method and vacuum evaporation method.

(2) As the base material, not only carbon steel but also other inexpensive metals may be used, and it is also possible to partially use synthetic resin.

■ It is also applicable to other types of plasma processing equipment equipped with multiple plasma injection tubes.

Effects of the Invention As detailed above, the plasma processing apparatus of the present invention uses materials that are inexpensive and have good workability for each base material such as the inner wall of the storage chamber, the plasma injection tube, the support disk, and the hanger that constitute the apparatus. Furthermore, an anti-oxidation coating is formed by painting, wet coating, or dry plating on the surface of these base materials, especially the surface of the hanger base material, which is exposed to a large amount of plasma irradiation.It has excellent corrosion resistance and is inexpensive to manufacture. This invention also exhibits the effect of being inexpensive and is an excellent invention as a plasma processing apparatus.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an embodiment of a plasma processing apparatus embodying the present invention, Fig. 2 is a perspective view of Fig. 1, Fig. 3 is a front view of the injection pipe, and Fig. 4 is a view of the injection pipe. 5 is a sectional view taken along the line A-A in FIG. 3, FIG. 6 is a sectional view taken along the line B-B in FIG. 3, and FIG. 7 shows the end of the hanger. It is an enlarged perspective view. 1. Containment chamber, 2. Exhaust port, 5. Injection port, 3. Plasma injection pipe, B. Synthetic resin bumper. Patent applicant Toyoda Gosei Co., Ltd. agent
Patent Attorney Hironobu Onda Figure 2 Drawing No. 4 Drawing No. WJ Figure 7

Claims (1)

[Claims] 1. A storage chamber (1) that accommodates objects to be painted such as synthetic resin bumpers (B), and a plasma injection device that is installed on the inner wall of the storage chamber (1) and injects plasma gas into the storage chamber (1). tube(
3), and an exhaust port (2) that depressurizes the inside of the containment chamber (1).
In a plasma processing apparatus equipped with a plurality of hangers (16) on which objects to be coated are placed, at least the hangers (16)
16) A plasma processing apparatus characterized in that an antioxidant coating (8) is formed on the surface of the base material.