JPH0114320B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides a plating method useful when forming a printing wheel used in a printing device such as a check writer by plating a plastic, and this method. The present invention relates to a plating device useful for carrying out.

[Conventional technology]

Conventionally, there has been known a method of forming a printing wheel body using plastic as an alternative to metal, and applying a plating coating to the outer surface.

Conventionally, a method as shown in FIG. 6 has been used to perform the plating process.

That is, the plating tank 1 is filled with the plating liquid 2, the nickel anode 3 is disposed on the outer periphery of the plating tank 1, and the cathode 4 is formed as a rack 40 in the center. This is done by fitting and locking a shaft mounting hole provided at the center of a resin dial 42, which is the object to be plated, into a branch rack 41 that projects in the radial direction, and then applying electricity.

[Problem that the invention seeks to solve]

By the way, in the conventional method shown in FIG. 6 above,
The current density is low at the circumference of the cathode located halfway, and conversely, the current density is high at the part near the anode, so the plating on one side of the printing wheel closest to the anode is thick, resulting in printing that is far from the anode. The plating on the other side of the ring becomes thin. Therefore, when observing the cross section of the outer circumference of the printing wheel, the plating on one side is thick and the plating on the other side is thin.

In addition, in the above conventional method, the current density is low in the central part of the plating bath because the printing wheels are densely arranged, while the current density is low in the upper and lower parts because the degree of crowding is low. The height increases and the thickness becomes thicker.

Furthermore, since a part of the outer circumferential surface of the printing wheel to which plating is applied faces other printing wheels, the current density is low in areas where the distance from other printing wheels is close, and the plating thickness is thinner. Put it away.

As described above, the conventional plating method shown in FIG. 6 cannot uniformly plate the printing wheel for the various reasons mentioned above.

In view of this, the present invention aims to reduce the thickness of the plastic body, which is thick and non-uniform on the circumference, without damaging the tip shape of the outer periphery of the plastic body formed in the shape of a disc, that is, the outer surface shape of the type engraved on the outer periphery. The purpose is to realize a highly reliable metal coating without causing any damage.

[Means for solving problems]

The present invention was proposed in order to solve the above-mentioned conventional problems, and is a method and a plating apparatus for plating an object to be plated, such as a printing wheel of a printer, to a uniform film thickness.

That is, in the present invention, a rod-shaped rack is inserted into each shaft mounting hole of a plurality of printer printing wheel bodies made of plastic and having a shaft mounting hole formed in the center, and the printer printing wheels to which the plurality of printer printing wheels are attached are fitted. Plating is applied to the printer printing wheel main body by rotating the printer printing wheel main body in the plating bath facing the fixed anode and revolving around the cathode while energizing the printer printing wheel main body while alleviating the concentration of current density near the main body. A plating tank, a cathode shaft disposed in the center of the plating tank, and an object to be plated that revolves and rotates about the cathode shaft at a predetermined distance from the circumferential surface of the cathode shaft. a rack on which a plurality of objects to be plated are stacked, conductive auxiliary cathode plates attached to the top and bottom ends of the objects to be plated stacked on the rack, and a conductive auxiliary cathode plate fixed near the rack. This is a plating device having an anode.

〔Example〕

Next, one embodiment of the present invention will be described in detail with reference to FIGS. 1 to 3.

Reference numeral 1 denotes a plating tank, and the interior of the plating tank 1 is filled with a plating liquid 2. Further, a cathode shaft 3 is disposed in the center of the plating tank 1.
The lower end 3a of the cathode shaft 3 protrudes downward through the bottom wall 1a of the plating tank, and is inserted into a cathode current-carrying box 4 filled with a conductor such as mercury.

Further, the cathode shaft 3 is rotated by the driving force of the drive motor 6 being transmitted by a bevel gear 5 fitted onto the shaft 3. Furthermore, a hanger cathode receiver 7 is attached to the upper end 3b of the cathode shaft 3. A rack receiver 8 projects in the radial direction from the hanger cathode receiver 7, and a rack hanger 9 and a cathode energizing saddle 10 are arranged in two stages at the tip thereof. Furthermore, the above-mentioned rack receiver 8
A vertical rod 8a hangs downward from the middle part of the rod, and a ring-shaped rack lower end holder 8b is attached to the lower end of the vertical rod 8a.

Further, reference numeral 11 is a rack, and the object to be plated 12 can be inserted and attached through the center hole. A rack rotating roll 13 is attached to the upper end of the rack 11, the neck region of this roll 13 is supported by the rack hanger 9 and the cathode current carrying saddle 10, and the lower end is supported by the rack lower end supporter 8b. .

In addition, the hanger cathode receiver 7, the rack receiver 8,
The rack hanger 9, cathode current carrying saddle 10, etc. are all made of copper, brass, or stainless steel with good conductivity.
The object to be plated 12 is formed using steel or the like.
is used as the cathode.

Although the racks 11 are not shown in FIG. 1, ten racks can be installed in this example.

Next, the roll 13 is moved to the rolling contact surface 14 of the easy rotation ring 14 disposed above the plating tank 1.
It is pressed against A. Note that the ring 14 is
For example, it is attached to the upper end of the support column 15 via a hinge 16.

Note that 17 is a Ni anode and a Cu ring 18
It is suspended by.

Therefore, in the above configuration, by operating the drive motor 6, the cathode shaft 3 is rotated, and accordingly, the entire rack receiver 8, which is integral with this shaft 3, is also rotated.

Furthermore, since the rack rotation rolls 13 attached above the racks 11 respectively mounted on the rack receivers 8 are in rolling contact with the rolling contact surface 14A of the rack rotation ring 14, the racks 11 are not rotated on their own axis. As a result, the object to be plated 12 is also rotated.

Therefore, by passing a current during the above rotation,
Current flows from the anode Cu ring 18 to the rack 11,
The object to be plated 1 integrated into this rack 11
2 will be plated.

Note that Figure 3 is a partially enlarged view of Figure 2.
As is clear from this figure, the objects 12 to be plated are attached to the rack 11 so as to be stacked by fitting the shaft attachment holes 12a. Above and below the group of objects 12 to be plated, auxiliary cathode plates 21 formed in a disc shape of stainless steel, copper, brass, etc. are attached via spacers 19 and fixed with nuts 20.

This auxiliary cathode plate 21 acts to alleviate concentration of current density at the top and bottom of the group of objects 12 to be plated.

As a method of energizing the rack 11 and the object 12 to be plated at the same potential, as shown in FIG. This can be easily achieved by Incidentally, the coil spring 22 is wound around the rack 11 and tightened to reduce its diameter. If the object to be plated 12 is inserted in this state and the spring 22 is released, the coil spring 22 will expand in diameter. hole 1
It will come into firm pressure contact with 2a.

Further, as shown in FIG. 5, a U-shaped current-carrying cup 23 is inserted between each of the stacked objects 12 to be plated, and this cup 23 is brought into contact with the side surface of each object 12 to be plated. Good too.

〔Effect of the invention〕

According to the present invention, since a plurality of printer printing wheels can be easily attached together in a columnar manner, the entire object to be plated can be downsized, and furthermore, the plating tank can be downsized.

Further, according to the present invention, plating is mainly applied only to the outer circumferential surface of the printing ring, and other unnecessary parts are not plated.

Furthermore, it is possible to "plate while alleviating the concentration of current density" and to disperse the current concentrated at the upper and lower ends of the printing wheel attached to the rack using "auxiliary electrodes", which is a specific structure of this structure. Therefore, it is possible to further eliminate variations in plating thickness due to differences in mounting position relative to the rack.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical sectional view of the plating tank, and FIG. 2 is a plan view thereof. Fig. 3 is an enlarged longitudinal cross-sectional view of the main part to explain the energization state of the rack and the object to be plated, Fig. 4 is an enlarged longitudinal sectional view of the main part showing an example of the energization method, and Fig. 5
The figures also show another example, in which A is a plan view of the cup, B is a side view of the cup, and C is an enlarged vertical sectional view of the main part showing the energized state. FIG. 6 is a schematic vertical sectional view showing a conventional example. 1... Plating tank, 3... Cathode shaft, 6... Drive motor, 11... Rack, 12... Object to be plated, 1
4...Easy rotation ring, 17...Ni cathode, 18...Anode Cu ring.

Claims (1)

[Scope of Claims] 1. A rod-shaped rack is inserted into each shaft mounting hole of a plurality of printer printing wheel bodies made of plastic and having a shaft mounting hole formed in the center, and the plurality of printer printing wheels are attached. While alleviating the concentration of current density near the ring body, the printer printing wheel body is rotated in a plating bath facing a fixed anode and is energized while revolving around the cathode. How to tack. 2. A plating tank, a cathode shaft disposed in the center of the plating tank, and a plurality of objects to be plated that revolve and rotate about the cathode shaft at a predetermined distance from the circumferential surface of the cathode shaft. a rack to which the objects to be plated are mounted; conductive auxiliary cathode plates attached to the uppermost and lowermost ends of a plurality of objects to be plated stacked on the rack; and an anode fixedly disposed near the rack. Metsuki device.