JPS6184390A - Method and device for partial plating - Google Patents

Abstract

PURPOSE:To plate partially the inside peripheral surface of a cylindrical member, etc., as desired by using the inside space of a member to be plated as a plating cell and supplying successively an electrolytic cleaning liquid, washing water and plating liquid through a supply passage to said cell. CONSTITUTION:A work 1 is fixed via a seal ring 3 onto a receiving base 2. The electrolyte in an electrolyte cell 13 is fed to an electrode 4 and is run through a nozzle 5 into the inside space 6 of the work 1. Part thereof flows through a drain passage 7 into a liquid level adjusting tank 8, falls from a drain path 12 into a receiving tank 23 and returns the cell 13. The electrolyte in the space 6 is discharged therefrom upon ending of electrolytic cleaning. The washing water is then fed from a supply pipe 21 to clean the inside of the work 1. The plating liquid is thereafter fed to the electrode 4 from a plating liquid cell 14 and is supplied to the inside surface of the work 1 from a nozzle 5 to form a plating layer on the inside surface of the work 1. The supply of the electrolytic cleaning liquid, washing water and plating liquid is exchanged by changing-over of respective solenoid valves 19, 22, 20.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a partial plating method and apparatus suitable for, for example, partially plating the inner peripheral surface of a cylindrical member.

(Prior art) For example, a part of the inner peripheral surface of the cylinder head of a hydraulic cylinder (
Adds corrosion resistance to wiper seals and U-ring grooves [
From 1st to 1st, galvanizing may be applied.

There are two methods for this: masking off parts that do not need to be plated with tape, etc., and then plating by immersing them in a plating bath; and another method, which involves dipping the parts to be plated without using a plating bath and soaking them in the plating solution. There is a brush plating method in which plating is performed by pressing an electrode (the outer periphery of a conductor is coated with cotton or the like and impregnated with a plating solution) against the inner surface.

(Problem 7α to be solved by the invention) However, in this case, the former requires man-hours and costs for masking parts of the member to be plated that do not need to be plated, resulting in poor productivity, and the electrolytic layer and plating tank are separated. There is also the problem that the device needs to be provided, which increases the size of the device.

On the other hand, the latter has excellent transportability of the device itself, but the electrode needs to be manufactured each time according to the shape of the member to be plated, and the workability of replacing it is poor, and the electrode is attached to the sliding part. Also, the plating solution and other chemicals are highly concentrated and disposable, making disposal difficult and costly.

The present invention aims to solve such problems.

(Means for solving problems) The present invention comprises the following method and apparatus.

1. A member to be plated is placed on a pedestal having a supply passage and a discharge passage so that the internal space of the member to be plated communicates with both passages, and an electrode and a member to be plated arranged in this internal space are placed. While applying a predetermined voltage to the opening of the member, the electrolytic solution, cleaning water, and plating solution are sequentially supplied through the supply passage, and the level of these supplied liquids is adjusted up and down as necessary, so that the inside of the member to be plated is A method in which a space is used as a plating tank and a plating layer is formed on its inner surface.

2. An electrode is arranged on the pedestal on which the plated member is placed via a seal ring, and a supply passage and a control passage are formed, and a liquid level adjustment tank is provided in communication with the discharge passage. An electrolytic solution tank and a plating solution tank are disposed at the bottom of the adjustment tank, and receiving tanks for selectively guiding the liquid flowing out from the liquid level adjustment tank are freely movable in these eight tanks. This device is equipped with a pump that selectively supplies each liquid in the electrolytic solution tank and the plating solution tank, and is also equipped with means for selectively supplying cleaning water.

Therefore, by placing the workpiece to be plated on the pedestal and using this internal space as a plating tank, the electrolyte, cleaning water, and plating solution are fed in sequentially while adjusting the liquid level. A plating layer is formed.

(Example) Specific examples of the present invention will be described below based on the drawings.

In Fig. 1, 1 is a cylinder head (workpiece) as a member to be plated, and a seal ring 3 is placed on the top of a pedestal 2.
It is placed through.

An electrode 4 is provided at the center of the pedestal 2, and this electrode 4 projects into the internal space 6 of the workpiece 1. The electrode 4 is formed in a hollow shape, and a plurality of seven nozzles 5 are formed in the upper part thereof, and constitutes a supply passage through which an electrolytic solution and a plating solution are supplied, as will be described later.

The cradle 2 has a discharge passage 7 communicating with the internal space 6 of the workpiece 1.
is formed, and this discharge passage 7 communicates with a liquid level adjustment tank 8. The liquid level adjustment tank 8 is provided with a partition wall 9 for adjusting the liquid level inside thereof, and a liquid level adjustment plate 10 is attached to the upper part of the partition wall 9 so as to be freely raised and lowered, and a small diameter passage 11 is formed in the lower part. be done.

The liquid that has passed through the liquid level adjustment 'M8 is led to the drainage channel 12.

On the other hand, 13 is an electrolytic solution tank containing an electrolytic solution, 14 is a plating solution tank containing a plating solution, and pumps 15 and 16, respectively.
The electrolytic solution or the plating solution is selectively fed into the internal passage of the electrode 4 by means of the pipes 17, 18 and the solenoid valves 19, 20.

Further, a water supply pipe 21 is connected to the electrode 4, and cleaning water is also supplied to the electrode 4 by opening the electromagnetic valve 22.

Receptacle tanks 23 and 24 are provided above the electrolytic solution MN13 and the plating solution tank 14, respectively, and each receiver tank 23.2
4 can be moved horizontally by air cylinders 25.26.

In other words, the receiving tanks 23, 24 are positioned directly below the drainage channel 12 when the air cylinder 25, 26 is expanded, and are movable so that they are removed from the drainage channel 12 when the air cylinders 25, 26 are contracted.
When located directly below the drainage channel 12, drain pipes 27 and 28 are installed so that the liquid received from the drainage channel 12 can be dropped into the electrolytic solution tank 13 and the plating solution tank 14, respectively.

Further, a drainage tank 29 is provided between the electrolytic solution tank 13 and the plating solution tank 14, and each of the receiving tanks 23 and 24 is connected to the drainage channel 1.
It is designed to receive the washing water discharged from the drain channel 12 when the drain channel 2 is removed from directly below the drain channel 12.

In order to flow a predetermined plating current between the electrode 4 and the pedestal 2, the electrode terminals 31 and 32 from the rectifier 30 are connected to the electrode 4.
It can be connected to the pedestal 2.

In the above configuration, first, the work 1 is placed on the pedestal 2, and the work 1 is fixed by a fixing means (not shown) as necessary. In this case, the seal ring 3 on the lower surface of the workpiece 1 maintains the sealing performance between the workpiece 1 and the pedestal 2.

After connecting the electrode 4 to the (10) side and the workpiece 1 to the (-) side, open the solenoid valve 19 and use the pump 15 to send the electrolyte in the electrolyte tank 13 to the electrode 4 through the pipe 17. At the same time, the air cylinder 25 is extended to move the receiving tank 23 directly below the drainage channel 12.

The electrolytic solution from the pump 15 flows out into the internal space 6 of the workpiece 1 through the nozzle 5 of the electrode 4, and a portion flows into the liquid level adjustment tank 8 through the discharge passage 7. Furthermore, the electrolytic solution overflows the liquid level adjustment plate 10 of the liquid level adjustment tank 8, falls into the receiving tank 23 of the F part through the drainage channel 12, and returns to the electrolytic solution tank 13 again.

In the liquid level adjustment tank εj, the electrolyte also flows out from the passage 11 at the bottom of the partition wall 9, but the supply flow rate from the pump 15 is set to be excessive so that the liquid level adjustment plate 10 will definitely overflow. Therefore, the internal space 6 of the workpiece 1 communicating with the workpiece 1 is filled with the electrolytic solution to the same level as the liquid level adjusting plate 1( ).

=7- The liquid level of the electrolytic solution in the workpiece 1 is determined according to the area to be plated, and can be freely adjusted by moving the liquid level adjusting plate 10 up and down.

When the electrolytic solution is thus circulated for a predetermined period of time and electrolytic cleaning is completed, the pump 15 is stopped and the solenoid valve 19 is closed.

When the electrolyte supply is stopped, the entire amount of electrolyte in the internal space 6 of the workpiece 1 completely flows out through the bottom passage 11 because the passage 11 at the bottom of the liquid level adjustment tank 8 is always open. do.

Next, the electromagnetic valve 22 is opened to send cleaning water from the water supply pipe 21 to clean the inner surface of the workpiece 1.

In this case, the air cylinder 25 is contracted to move the receiving tank 23 from the lower surface of the drainage channel 12, and after washing the workpiece 1 with water, the washing water flowing out from the drainage channel 12 is made to flow into the drainage receiving tank 29.

When the predetermined water washing process is completed, the solenoid valve 22 is closed to stop the water supply.

The cleaning water completely flows out from the workpiece 1 and the liquid level adjustment tank 8 in the same manner as described above.

Thereafter, the solenoid valve 20 is opened, the air cylinder 26 is extended, the receiving tank 24 is moved directly below the drainage channel 1.2, and the pump 16 is driven.

Then, the plating solution from the plating solution tank 14 is sent to the electrode 4 via the pipe 18 and is supplied into the workpiece 1 from the nozzle 5.

The plating solution rises to the predetermined level in the same way as above,
The surplus passes through the liquid level adjustment tank 8 and the receiving tank 24 to the plating liquid tank 1.
Returned to 4.

In this way, the inner surface of the workpiece 21 is immersed in the plating solution up to a predetermined position, and at the same time, when a plating current is supplied from the rectifier 30, a plating layer is formed on the inner surface of the workpiece 1.

When the plating layer reaches a predetermined thickness, the electricity to the electrode 4 is stopped, the solenoid valve 20 is closed, and the pump 16 is turned off.
By stopping the plating solution, the supply of plating solution is stopped. As a result, all the plating solution flows out from inside the workpiece 1 and is collected in the plating solution tank 14.

Finally, the electromagnetic valve 22 is opened again and the cleaning water is jetted from the nozzle 5 toward the inner surface of the workpiece 1, thereby cleaning the formed plating layer. At this time, the receiving tank 24 is moved, and the washing water falling from the drainage channel 12 is discharged from the drainage receiving tank 29.

When cleaning is completed, the workpiece 1 is removed from the pedestal 2, the next workpiece 1 is newly placed, and the same operation as above is repeated.

In this way, the present invention performs internal plating while using the internal space 6 of the workpiece 1 as a plating bath.
By adjusting the height of the liquid level, a plating layer can be easily formed on any part.

In this embodiment, the electrolytic solution and the plating solution are supplied through the inside of the electrode 4, but of course a supply passage may be provided separately from the electrode.

It is also possible to adjust the height of the liquid level by regulating the relationship between the supply (2) and the outflow amount using, for example, a flow rate control valve.

(Effects of the Invention) As described above, according to the method of the present invention, it is possible to arbitrarily apply inner plating to only necessary parts without masking or using electrodes that match the shape of the part to be plated, improving work efficiency. Although it is expensive, it is possible to achieve significant cost reduction.

In addition, since the WI space inside the part to be plated is used as a plating tank and cleaning tank, there is no need to install each girder separately, and the part to be plated does not need to be moved during the plating process, making it easier to plating. It can be done safely and efficiently.

According to the apparatus of the present invention, once the member to be plated is set, processing is performed continuously, so the work efficiency is extremely high.

Furthermore, since the electrolyte and plating solution used for plating are recovered and reused, they are much more uniform than disposable ones.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an apparatus for implementing the present invention. 1... Part to be plated (work), 2... cradle, '3
...Seal, 4...Electrode, 5...Nozzle, 6...
・Internal space, 7...-M1 outlet passage, 8... Liquid level adjustment tank, 9... Partition wall, 1()... Liquid level adjustment plate, 12.
... Drainage channel, 13... Electrolyte tank, 1.1... Plating PgLWI, + 5.16... Pump, 19,2
0.22... Solenoid valve, 23.24... Receiving tank, 25.
26...Air silling, 29...Drainage tank, 30.
··rectifier. Patent Applicant Kayaba Kogyo Co., Ltd. Procedures tiaE Book August 1988 1988 Patent Order No. 184941 2 Title of Invention Partial Plating Method and Apparatus 3 Relationship with the Amendment Person Case Address of Patent Applicant 2-4-1 Hamamatsucho, Minato-ku, Tokyo World Trade Center Building Name (092) Kayaba Kogyo Co., Ltd. 4, Agent 5, Date of amendment order Voluntary 6, Specification subject to amendment 1 "Claims 1 F Invention Details! Brief explanation of aspects - Column 1 and drawings. 7. Contents of amendment (1) The scope of claims in the specification is amended as shown in the attached sheet. (2) Starting from page 3, line 12 of the same. Toward the 13th line, “
``Also, electrolytic layer,'' should be corrected to ``Also, electrolytic cleaning liquid tank.'' (3) Page 4, line 10, page 5, line 6, page 5, line 19 to line 2 (), page 6, line 10, page 66, line 14 , page 8, line 5, page 8, line 8, page 8, lines 10 to 11, page 8, line 15, page 8, line 19, line 9 Page 1st line, 9th
"Electrolyte" on page 7, line 9, page 9, line 9, page 11, line 13 to line 14, page 12, line 13
Correct the statement to "electrolytic cleaning solution". (4) From line 18 to line 19 on page 4, line tjl&i on page 5, line 10 on page 6, line 19 on page 6
line, page 7 Ij line 141, page 7 line 1(), page 8 line 5, page 8 line 13, page 13 line 2 [Electrolyte tank-1 (5) Insert the following sentence between lines 15 and 16 of the same No. 6 TX. At this time, the bypass valves 19A and 2OA are opened to circulate the electrolytic cleaning liquid and the plating liquid from the pumps 15 and 16 to the electrolytic cleaning liquid tank 13 and the plating liquid tank 14, respectively. -1 (6) Correct the statement ``pedestal 21'' on page 7, line 15 and page 7, line 17 to read 1'' workpiece 1-1. (7) From line 4 to line 6 of page 9 [After the electrolyte is circulated for a predetermined period of time and the electrolytic cleaning is completed, the pump 15 is turned to 1 and the solenoid valve 19 is closed. -1 is 1. In this way, current is supplied from the rectifier 3 () for a predetermined period of time, and the electrolytic cleaning solution is circulated to complete the electrolytic cleaning, and then the solenoid valve 19 is closed. Correct it to -1. (8) In the 8th line of the 9th line of the same page, [Since it is always open, the 1 indicates that it is always open and that the piping from the lower end of the electrode 4 to the drain channel 12 is always open. Since it is open, it is corrected to 1. (9) In the 17th line of page 9, 1-predetermined water washing process is 1, which is corrected to [predetermined water washing process is -1]. (10) Page 1 (), lines 2 to 3? ? 11 and moves directly below the I drainage channel 12 to drive the pump 16. " is corrected to "move directly below the drainage channel 12. 1." ,
Stop supplying plating solution. ” [Solenoid valve 20
Close the plating solution and stop supplying the plating solution (Jli. Correct it to -1. In the example, it is corrected to -1. (13) Insert the following sentence between page 11, line 18 and line #19. Multiple pretreatment tanks (such as electrolytic cleaning tanks) and plating tanks may be installed, and the plating pretreatment process may be, for example, alkaline degreasing → water washing → electrolytic cleaning → water washing, or the plating layer may be two or three layers. To improve the cleaning effect, supply air at the same time as cleaning water and perform air agitation.
After draining the liquid, air blowing is performed to drain the liquid to increase liquid recovery efficiency, and rectifiers for electrolytic cleaning and plating are installed separately to obtain the optimal processing conditions for each. It is possible. (14) On page 12, line 7, the phrase ``and in the plating process'' is corrected to ``and in the plating process.'' (15) From the 19th line to the 20th line of page 12, "3... seal" is corrected to "3... seal ring". (16) Figure 1 of the drawings will be corrected as shown in the attached sheet. Claims [1. A member to be plated is placed on a pedestal having a supply passage and a discharge passage in such a way that the inner space of the member to be plated communicates with both passages, and the member is placed in this inner space. 1. A partial coating method, characterized in that a predetermined voltage is applied between the applied electrode and the member to be plated, while a plating layer is formed electrolytically through the supply passage. 2. An electrode is arranged on the pedestal on which the plated member is placed via a seal ring, and a supply passage and a discharge passage are formed, and a liquid level adjustment tank is provided in communication with the discharge passage, and the liquid level is adjusted. A plating liquid tank is located at the bottom of the tank, and a freely movable receiving tank is installed in each of these girders to selectively guide the effluent from the liquid level adjustment tank. , the supply passage is provided with a pump for selectively supplying each solution of the second vinegar color 11 and the plating solution tank, and further provided with a means for selectively supplying cleaning water. Partial plating equipment. 3. The height of the internal partition wall is
The partial plating apparatus according to item 2 of the scope of Patent M, characterized in that the liquid level can be freely adjusted via a liquid level adjusting plate.

Claims (1)

[Claims] 1. A member to be plated is placed on a pedestal having a supply passage and a discharge passage in such a way that the inner space of the member to be plated communicates with both passages, and the member is placed in this inner space. While applying a predetermined voltage between the electrode and the member to be plated, the electrolytic solution, cleaning water, and plating solution are sequentially supplied through the supply passage, and the level of these supplied liquids is adjusted up and down as necessary. , a partial plating method characterized by forming a plating layer on the inner surface of a member to be plated while using an internal space as a plating tank. 2. An electrode is arranged on the pedestal on which the plated member is placed via a seal ring, and a supply passage and a discharge passage are formed, and a liquid level adjustment tank is provided in communication with the discharge passage, and the liquid level is adjusted. An electrolytic solution tank and a plating solution tank are arranged at the bottom of the tank, and each tank is provided with a freely movable receiving tank that selectively guides the liquid flowing out from the liquid level adjustment tank. A partial plating apparatus characterized by being equipped with a pump for selectively supplying each liquid in an electrolytic solution tank and a plating solution tank, and further equipped with a means for selectively supplying cleaning water. 3. The partial plating apparatus according to claim 2, wherein the height of an internal partition wall of the liquid level adjustment tank is adjustable via a liquid level adjustment plate. 4. The partial plating apparatus according to claim 2 or 3, wherein the supply passage is formed through the inside of the electrode.