Electrolysis: processes – compositions used therein – and methods – Electrolytic coating – Coating moving substrate
Reexamination Certificate
2000-11-06
2002-10-29
Wong, Edna (Department: 1741)
Electrolysis: processes, compositions used therein, and methods
Electrolytic coating
Coating moving substrate
C205S145000, C205S104000
Reexamination Certificate
active
06471846
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to an electric feeding method and apparatus for a continuous plating apparatus for continuously feeding electric power to articles to be plated.
2. Description of the Related Art
Conventionally, in order to plate planar articles, a plurality of articles to be plated are individually mounted by fasteners on a frame member connected to cathodes, and the articles are removed individually after the completion of plating. However, this method is time-consuming, and causes a hindrance against plating work.
Therefore, recently, an approach has been proposed in which, without fixing the articles to the frame member, the articles to be plated are continuously fed into a plating bath one by one, and the articles to be plated are moved in a vertical direction within the plating bath to thereby continuously effectively plate the articles.
FIG. 7
is a cross-sectional view showing an example of a continuous plating apparatus that may perform continuous plating. A V-shaped rail
2
in cross section extending in a vertical direction to the paper surface is provided in the vicinity of a central bottom of a plating bath
1
. An article
3
to be plated such as a printed circuit board is held in the vertical direction with its lower edge being laid on the rail
2
. Both surfaces of the article
3
are clamped by electric supply rollers
5
fixed to vertical rotary electrode shafts
4
. The electric supply rollers
5
are rotated together with the rotary shafts
4
so that the article
3
to be plated is moved horizontally on and along the rail
2
under the condition that the article
3
is dipped in plating liquid
6
. Then, anodes
8
which may move vertically by cylinders
7
and shielding plates
9
for preventing turbulence are provided in the plating liquid
6
.
Wheels
10
are mounted at suitable positions of the rotary shafts
4
and pressing members
12
pressed by springs
11
are brought into contact with the wheels
10
. The pressure force of the springs
11
is transmitted from the wheels
10
through the rotary electrode shafts
4
to the electric supply rollers
5
so that the contact between the electric supply rollers
5
and the article
3
to be plated is ensured and the flow of the electricity to the surfaces of the article
3
is made uniform.
Thus, the surfaces of the article
3
to be plated are charged with a negative potential from the rotary electrode shafts
4
through the electric supply rollers
5
so that the current flows from the anodes
8
to perform the continuous plating.
The circumferential surfaces of the electric supply rollers
5
which are brought into contact with the articles
3
to be plated are coated with a protection film which is made of titanium nitride on, for example, a nickel plated film that is harder than the plating coating to be applied, such as a copper film. Brushes
14
are pressed against the circumferential surfaces of the electric supply rollers
5
by springs
13
so that the plating formed on the circumferential surfaces of the electric supply rollers
5
may be removed.
Since each of the conventional electric supply rollers
5
as a whole is formed into a single conductive member, the current always flows also through a portion which is out of contact with the article
3
to be plated and a plating is formed on the electric supply rollers
5
as a whole.
Even if the brushes
14
are depressed against the circumferential surfaces of the electric supply rollers
5
by the springs
13
as mentioned above, it is difficult to remove the plating adhered over the entire electric supply rollers
5
. Due to the accumulated plating, the electric supply rollers
5
are damaged so that the serve life thereof is shortened. A current will not uniformly flow through the articles to be plated. As a result, it is impossible to perform the plating work.
SUMMARY OF THE INVENTION
According to the present invention, an electric feeding method of continuously electroplating a planar article comprising:
providing a plating apparatus having an anode, a cathode for flaking, and at least two rotary electrode shafts, each of said rotary electrode shafts having at least one electric supply roller mounted thereon;
dividing each of the electric supply roller in a circumferential direction into at least one conductive segment and at least one non-conductive segment;
clamping both sides of the planar article by the electric supply rollers such that the planar article is vertical;
moving the planar article horizontally through the plating apparatus by the rotation of the electric supply rollers;
electrically charging said at least one electric supply roller of said rotary electrode shafts so that the conductive segment in contact with the planar article has a negative potential; and
electrically charging said at least one electric supply roller of said rotary electrode shafts so that the conductive segment at a distance from the planar article has a positive potential, and an electric current flows between the cathode and the conductive segment which has the positive potential; is provided.
In the claimed method, the electric supply roller is divided into conductive and non-conductive segments and a planar article is plated by supplying a negative charge only to the conductive segment in contact with the planar article. The non-conductive segment and the conductive segment not in contact with the article of the same electric supply roller are prevented from undesirable plating. On the other hand, when the segment comes around to the opposite side of the electric supply roller by its rotation, a positive charge is supplied to the conductive segment. Thus, undesirable plating, which has adhered on the conductive segment charged negatively, elutes or flakes into a plating liquid so that the undesirable plating can be removed. Accordingly, the electric supply roller can be used for a longer term and the planar article can be uniformly plated by allowing a uniform electric current to flow to the planar article.
When the conductive segment of the electric supply roller rotates to the place at a distance from the planar article, an electric current flows between the conductive segment having a positive potential and the cathode, which pairs with the conductive segment. The cathode is provided in order to attract metal flakes, which are removed from the electric supply roller. The electric current flow is formed by supplying positive and negative charges from the same eliminator to the conductive segment and the cathode, respectively. The current flow results in drawing metallic flakes removed from the electric supply roller to the cathode, thus, the formation of a granulated surface by adhesion of the flakes on the plating face can be prevented.
Moreover, in the method of the present invention, a planar article is sandwiched between a pair of electric supply rollers so that the planar article is positioned vertically and conveyed by the pair. When a planar article has via holes, air inside them spontaneously flows out because of the rendering of the planar article vertical. Then, the insides of the via holes can be easily plated.
An electrical collection disk may be provided on an upper portion of each rotary electrode shaft, out of the plating liquid, in order to allow an electric current to flow to the electric supply roller. The electrical collection disk has conductive and nonconductive segments respectively corresponding to the conductive and non-conductive segments of the electric supply roller in phase in the circumferential direction. The electric supply roller and the electrical collection disk are fixed to the rotary electrode shaft in circumferential phase and are uniformly rotated by rotation of the shaft. Thereby, the electric supply roller can be efficiently charged via the rotary electrode shaft by contacting an electrode with the electrical collection disk.
The boundary between the conductive segment and the non-conductive segment is desirably formed to be vertical in the
Flynn ,Thiel, Boutell & Tanis, P.C.
Wong Edna
LandOfFree
Electric feeding method and apparatus for a continuous... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Electric feeding method and apparatus for a continuous..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Electric feeding method and apparatus for a continuous... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2982823