JP2021075741A - Rotary type plating device - Google Patents

Abstract

To provide a rotary type plating device capable of decreasing defective plating resulting from bubbling occurring in a plating solution.SOLUTION: A rotary-type plating device 100 comprises a plating tank 3 rotatable in the normal and reverse directions on a vertical rotary shaft 17, an anode 4 disposed approximately on the inner center of the plating tank 3, an anode bag 16 surrounding the anode 4, an anode cap 10 holding the anode 4 and the anode bag 16, and a cathode 5 disposed on the outer periphery side of the plating tank 3. The anode cap 10 is constituted of a cap base 24 and a cap cover 25. A plurality of air outlet parts 26 are provided on the lower face of a protruding part 24a of the cap base 24. A recessed groove 24b and a gap G (air supply path) communicating with the plurality of air outlet parts 26 are provided between the cap base 24 and the cap cover 25.SELECTED DRAWING: Figure 3

Description

The present invention relates to a rotary plating apparatus used for plating electrodes of chip-type electronic components, for example.

Small electronic components such as chip-type resistors are electrolytically plated to form external electrodes in order to improve solderability to circuit boards and ensure electrical continuity. As a plating device for forming such an external electrode, an object to be plated and a plating solution are put into a plating tank, and the plating tank is rotated to bring the object to be plated into contact with a cathode electrode provided on the outer peripheral portion. A rotary plating apparatus that performs electrolytic plating on an object to be plated is known (see, for example, Patent Document 1).

The rotary plating apparatus disclosed in Patent Document 1 includes a disk-shaped bottom plate that can rotate around a vertical rotation axis, a conical trapezoidal lid integrally provided on the outer peripheral side wall of the bottom plate, and the like. A plating tank defined by these bottom plates and a lid, a box-shaped anode electrode arranged substantially in the center of the plating tank, and a ring-shaped cathode electrode provided on the outer peripheral side wall of the bottom plate are provided. The object to be plated and the plating solution are stored in the plating tank.

In the rotary plating apparatus configured in this way, the plating tank alternately repeats forward rotation and reverse rotation around the rotation axis, and the rotation is maintained and the object to be plated is pressed against the cathode electrode by centrifugal force. The plating process is performed by energizing between the anode electrode and the cathode electrode only for a short time.

JP-A-2018-178181

When the plating tank is alternately rotated in the forward rotation direction and the reverse rotation direction to perform the plating treatment as in the rotary plating apparatus described in Patent Document 1, the object to be plated and the plating solution are agitated and become the object to be plated. A uniform plating layer can be formed. However, when the plating tank is rotated alternately in the forward rotation direction and the reverse rotation direction to perform the plating process, bubbles are formed in the plating solution, and these bubbles tend to collect in the center of the plating tank when the rotation direction of the plating tank is switched. Therefore, many bubbles are concentrated around the anode electrode arranged in the central portion of the plating tank, and the object to be plated is pushed up by the bubbles and easily adheres to the anode electrode.

In particular, in the case of an object to be plated with a small external dimension, the anode electrode is surrounded by a cloth anode bag to prevent the object to be plated from flowing in, so that the object to be plated pushed up by bubbles gets entangled with the anode bag. It becomes difficult to separate. As a result, even if the plating tank is rotated again after stopping, the object to be plated that is entwined with the anode bag cannot get on the flow of the plating solution and cannot contact the cathode when energized. There was a risk that plating defects would occur frequently.

The present invention has been made in view of such an actual situation of the prior art, and an object of the present invention is to provide a rotary plating apparatus capable of reducing plating defects caused by foaming generated in a plating solution. ..

In order to achieve the above object, the rotary plating apparatus of the present invention has a disc-shaped bottom plate that can rotate in both forward and reverse directions about a vertical line axis, and a conical base integrally provided on the outer peripheral side wall of the bottom plate. It holds a lid having a shape, a plating tank defined by the bottom plate and the lid, a box-shaped anode electrode arranged substantially in the center of the plating tank, and an upper end portion of the anode electrode. An anode cap and a cathode electrode that is exposed on the inner peripheral side of the plating tank and forms a part of the outer peripheral side wall are provided, and air is blown onto the anode cap toward the outer peripheral side of the anode electrode. The feature is that a part is provided.

In the rotary plating apparatus configured in this way, bubbles are generated in the plating solution, and even if the bubbles gather around the anode electrode when the plating tank is stopped to switch the rotation direction, the bubbles are provided on the anode cap. By blowing air from the air blowing part toward the outer peripheral side of the anode electrode, it becomes difficult for the object to be plated pushed up by the bubbles to adhere to the anode electrode, so plating defects such as unplated or abnormal plating may occur. It can be reduced.

In the rotary plating apparatus having the above configuration, the anode electrode is surrounded by an anode bag having a filter function such as cloth, and when air is blown from the air blowing portion toward the outer peripheral side of the anode bag, the anode bag Therefore, it is possible to prevent the object to be plated from being entangled with the anode bag while preventing the object to be plated from flowing into the anode electrode.

Further, in the rotary plating apparatus having the above configuration, the anode cap includes a cap base for holding the anode electrode and a cap cover joined and integrated so as to cover the cap base, and these cap base and cap cover are provided. It is preferable that an air supply passage leading to the air blowing portion is provided between the anode cap and the anode cap because the air supply passage can be easily formed.

In this case, if a configuration is adopted in which the cap base has a protruding portion that protrudes radially outward from the anode bag and an air blowing portion is provided on the lower surface of the protruding portion, the air blowing portion radiates from the air blowing portion. The air ejected from the anode electrode and the outer peripheral surface of the anode bag can be efficiently blown.

The shape and size of the air blowing portion are not particularly limited, but if a plurality of air blowing portions are provided on the lower surface of the protruding portion at predetermined intervals in the circumferential direction, bubbles are generated by a small amount of air supplied. It can be blown off efficiently.

Alternatively, it is also possible to adopt a configuration in which the cap base has a protruding portion protruding outward from the anode bag, and the air blowing portion is provided in an annular shape between the protruding portion and the cap cover. Then, the air blowing portion can be easily formed.

According to the rotary plating apparatus of the present invention, it is possible to reduce plating defects caused by foaming generated in the plating solution.

It is a perspective view which shows by breaking a part of the rotary plating apparatus which concerns on embodiment of this invention. It is explanatory drawing which shows typically the circulation route of the plating solution and the like in the rotary plating apparatus. It is explanatory drawing which shows the air supply path by the anode cap provided in the rotary plating apparatus. It is a figure which shows the part A of FIG. 3 enlarged. It is a back view of the anode cap. It is sectional drawing of the anode cap. It is sectional drawing of the main part which shows the modification of the anode cap.

Hereinafter, the embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view showing a part of the rotary plating apparatus according to the embodiment of the present invention.

As shown in FIG. 1, the rotary plating apparatus 100 according to the present embodiment includes a lid 1 having a substantially conical trapezoidal outer shape, and a bottom plate 2 arranged so as to close the bottom surface of the lid 1. A plating tank 3 defined by the lid 1 and the bottom plate 2, an anode electrode (anode electrode) 4 arranged substantially in the center of the plating tank 3, and a ring-shaped ring provided on the outer peripheral side of the bottom plate 2. It is configured to include a cathode electrode (cathode electrode) 5.

The lid 1 has a protrusion 1a in which the peripheral edge portion (outermost outer peripheral portion) of the lowermost end of the inclined side surface projects in a brim shape in the outer peripheral direction, and the protrusion 1a is covered with an annular ring member 6. There is. Further, a plurality of openings 1b for discharging the plating solution and the like stored in the plating tank 3 are provided in the lower portion of the inclined side surface of the lid 1 at predetermined intervals in the circumferential direction.

The bottom plate 2 has a disk-shaped base member 7 having the same outer diameter as the outer diameter of the outermost outer peripheral portion of the lid 1, and the cathode electrode 5 arranged along the outer peripheral edge portion on the upper surface side of the base member 7. And a spacer ring 8 which is located below the protrusion 1a of the lid 1 and is an annular member having the same diameter as the cathode electrode 5. In the plating tank 3, the outer peripheral side wall is formed by the outer peripheral edge portion of the base member 7, the cathode electrode 5, the spacer ring 8, and the protrusion 1a.

The ring member 6, the protrusion 1a, the spacer ring 8, and the cathode electrode 5 are provided with a plurality of through holes in the circumferential direction thereof. Then, in a state where these are overlapped, the bolt 9 is inserted into the through hole, and the male screw portion provided at the tip portion thereof and the female screw portion provided on the base member 7 are screwed together to form the lid body 1. And the bottom plate 2 are integrally fixed. The internal space formed by the lid 1 and the bottom plate 2 serves as the plating tank 3.

A box-shaped anode electrode 4 made of wire mesh is arranged in the center of the plating tank 3, and the anode electrode 4 is energized in the center of the anode cap 10 holding the anode electrode 4. The support shaft 11 of the above is inserted and fixed. Further, a flush water introduction pipe 12 and a treatment liquid introduction pipe 13 are inserted and fixed to the anode cap 10, and various treatment liquids are circulated to the plating tank 3 by the flush water introduction pipe 12 and the treatment liquid introduction pipe 13. And discharge.

Further, a liquid level sensor 14 is arranged on the side of the anode cap 10, and the liquid level sensor 14 and the anode electrode 4 penetrate the upper opening 1c provided at the top of the lid 1 and inside the plating tank 3. Has reached. The plating tank 3 stores the object to be plated 15 such as a chip type resistor and the plating solution (not shown), but in order to prevent the minute object 15 to be plated from flowing into the anode electrode 4. The anode electrode 4 is surrounded by an anode bag 16 having a filter function such as a cloth. Although the details will be described later, air is blown from the anode cap 10 toward the outer peripheral side of the anode bag 16.

A rotating shaft 17 extending in the vertical direction is coupled to the center of the bottom plate 2 on the lower surface side, and the rotating shaft 17 is connected from the negative side of the power supply for electrolytic plating to conduct a conductive member for energizing the cathode electrode 5. 18 are in contact. Then, by applying a rotational force to the rotating shaft 17 from a motor or the like (not shown), the plating tank 3 in which the object to be plated 15 and the plating solution (not shown) are stored is placed in the horizontal direction around the rotating shaft 17. It is designed to rotate. Specifically, as shown by the white arrows in FIG. 1, the plating tank 3 repeatedly rotates and stops at a predetermined speed by rotating in the clockwise direction and the counterclockwise direction (forward and reverse directions).

In this way, the plating tank 3 alternately repeats forward rotation and reverse rotation in the horizontal direction, the rotation is maintained, and the object to be plated 15 is pressed against the cathode electrode 5 by centrifugal force as shown in FIG. The plating process is performed by energizing between the anode electrode 4 and the cathode electrode 5 only for a time.

The target of plating by the rotary plating apparatus 100 according to the present embodiment is not limited to the chip type resistor, and for example, an electrode terminal such as a chip type inductor, a chip type capacitor, a composite component thereof, a multiple resistor, and the like. It can also be used for plating of electronic parts having.

FIG. 2 is an explanatory diagram schematically showing a circulation route of a plating solution or the like in the rotary plating apparatus 100 according to the present embodiment.

As shown in FIG. 2, in the rotary plating apparatus 100, when the plating solution is discharged from the opening 1b provided in the lid 1 as the plating tank 3 rotates, a new plating solution in the plating solution mother tank 19 is simultaneously discharged. The plating solution is supplied to the plating tank 3 via the treatment liquid introduction tube 13. Further, the plating liquid discharged from the opening 1b is received by the container 20 that covers the entire outside of the plating tank 3, and reaches the plating liquid mother tank 19 via the treatment liquid lead-out pipe 21.

When the treatment liquid is discharged due to the change of the plating type in the rotary plating apparatus 100, the plating tank 3 is rotated at a high speed in a predetermined direction, and the plating liquid or the like is discharged from the opening 1b by utilizing the centrifugal force at that time. I try to receive it in the container 20.

In the water washing step of the plated product, water washing water is supplied from the water washing water tank 22 into the plating tank 3 via the water washing water introduction pipe 12, and the water washing water after washing is also plated in the same manner as when the treatment liquid is discharged. This is performed by rotating the tank 3 at high speed and utilizing the centrifugal force. Then, the flush water received in the container 20 is returned to the flush water tank 22 via the flush water outlet pipe 23.

FIG. 3 is an explanatory view showing a supply path of air blown from the anode cap 10 to the anode bag 16, FIG. 4 is an enlarged view of part A of FIG. 3, and FIG. 5 is a back view of the anode cap 10 and FIG. Is a cross-sectional view of the anode cap 10.

As shown in FIGS. 3 to 6, the anode cap 10 is composed of a cap base 24 that holds the anode electrode 4 and the upper end of the anode bag 16 and a cap cover 25 that covers the cap base 24. The cap base 24 and the cap cover 25 are joined and integrated by using a fixing fastener for the support shaft 11, the washing water introduction pipe 12, and the treatment liquid introduction pipe 13.

The cap base 24 has a projecting portion 24a projecting in a brim shape in the outer peripheral direction on the peripheral edge portion of the upper end thereof, and an air blowing portion 26 is formed on the lower surface of the projecting portion 24a. A large number of air blowing portions 26 are formed at regular intervals in the circumferential direction of the protruding portions 24a, and in the present embodiment, 36 air blowing portions are maintained at equal intervals of 10 degrees in the circumferential direction of the protruding portions 24a. 26 is formed. A concave groove 24b extending in an annular shape is formed on the upper surface of the cap base 24 near the outer circumference, and each air is formed through the gap G secured in the upper surface of the cap base 24 and the lower surface of the cap cover 25. It communicates with the outlet 26.

The cap cover 25 has an annular wall 25a protruding upward on its peripheral edge, and a plurality of air supply portions communicating with the concave groove 24b of the cap base 24 are formed on the inner bottom surface surrounded by the annular wall 25a. 27 is provided. A tube 28 is connected to each air supply unit 27, and air is supplied from these tubes 28 into the recessed groove 24b via the air supply unit 27. At that time, if the air supply portions 27 are arranged at equal intervals along the circumferential direction of the concave groove 24b, air can be evenly and evenly supplied into the concave groove 24b. , Four air supply portions 27 are arranged at equal intervals of 90 degrees in the circumferential direction of the concave groove 24b.

The cap base 24 and the cap cover 25 are provided with a plurality of through holes 29, and the support shaft 11, the flush water introduction pipe 12, and the treatment liquid introduction pipe 13 are inserted into the through holes 29, respectively. ing. Further, a positioning portion 30 made of a combination of a concave portion and a convex portion is formed on the facing surface of the cap base 24 and the cap cover 25, and the positioning portion 30 facilitates the relative position of the cap base 24 and the cap cover 25. It is possible to align.

As described above, when the object to be plated 15 stored in the plating tank 3 is plated, the plating tank 3 is rotated alternately in the forward rotation direction and the reverse rotation direction so that the object to be plated 15 is agitated. Bubbles are generated in the plating solution. Then, when the rotation direction of the plating tank 3 is switched and stopped, the bubbles tend to collect in the center of the plating tank 3, so that many of them are around the anode electrode 4 and the anode bag 16 arranged in the center of the plating tank 3. The bubbles of the above are concentrated, and the object to be plated 15 pushed up by the bubbles may be entangled with the anode bag 16 to cause plating defects such as non-plating and abnormal plating.

In the rotary plating apparatus 100 according to the present embodiment, in order to prevent such plating defects, air is supplied to the air supply unit 27 provided on the cap cover 25 of the anode cap 10 via the tube 28. Air is supplied from each air blowing portion 26 formed in the protruding portion 24a of the cap base 24 to the anode bag 16 via the air supply passage (recessed groove 24b and gap G) formed between the cap base 24 and the cap cover 25. I try to spray it toward the outer circumference. As a result, even if the object to be plated 15 pushed up by the bubbles approaches the periphery of the anode bag 16, the object to be plated 15 is blown away by air together with the bubbles in the direction away from the anode bag 16, so that the object to be plated 15 is blown away. It becomes difficult to get entangled with the anode bag 16, and it is possible to reduce the occurrence of plating defects such as non-plating and abnormal plating.

At that time, since the air blowing portion 26 is formed in a hole shape on the lower surface of the protruding portion 24a of the cap base 24, as shown by the arrow in FIG. 4, the air ejected radially from the air blowing portion 26 is discharged into the anode bag. It can be sprayed on the outer peripheral surface of 16. Moreover, since a large number (for example, 36) of air blowing portions 26 are formed on the lower surface of the protruding portions 24a at regular intervals in the circumferential direction, bubbles can be efficiently blown off by a small amount of air supplied. The number of air blowing portions 26 is not particularly limited, but the larger the number of air blowing portions 26, the more efficiently the bubbles can be blown off, but on the other hand, the amount of air supplied increases, so these points should be taken into consideration. It may be set to an appropriate number.

As described above, in the rotary plating apparatus 100 according to the present embodiment, bubbles are generated in the plating solution when the plating tank 3 is stopped to switch the rotation direction, and the bubbles surround the anode electrode 4. Even if it gathers around 16, the air is blown from the air blowing portion 26 provided on the anode cap 10 toward the outer peripheral side of the anode bag 16, so that the object to be plated 15 pushed up by the bubbles is blown up. It becomes difficult to adhere to the anode bag 16, and it is possible to reduce the occurrence of plating defects such as non-plating and abnormal plating.

Further, in the rotary plating apparatus 100 according to the present embodiment, the anode cap 10 is joined and integrated with the cap base 24 for holding the anode electrode 4 and the anode bag 16 so as to cover the cap base 24. Since the anode cap 10 is composed of 25 and a concave groove 24b and a gap G (air supply passage) leading to the air blowing portion 26 are provided between the cap base 24 and the cap cover 25, air is provided in the anode cap 10. The supply passage can be easily formed.

Further, since the cap base 24 has a protruding portion 24a protruding outward in the radial direction from the anode bag 16, and a hole-shaped air blowing portion 26 is provided on the lower surface of the protruding portion 24a, the air blowing portion is provided. The air radially ejected from the 26 can be efficiently blown onto the outer peripheral surface of the anode bag 16. Moreover, since a large number of air blowing portions 26 are provided on the lower surface of the protruding portion 24a at predetermined intervals in the circumferential direction, bubbles can be efficiently blown off by a small amount of air supplied.

In the rotary plating apparatus 100 according to the present embodiment, the anode electrode 4 is surrounded by an anode bag 16 having a filter function such as a cloth, and air is blown from the air blowing portion 26 toward the outer peripheral side of the anode bag 16. Since the spraying is performed, it is possible to prevent the fine object to be plated 15 from flowing into the anode electrode 4 and to prevent the object to be plated 15 from being entangled with the anode bag 16. However, the anode bag 16 may be omitted, the anode electrode 4 may be formed of a fine wire mesh, and air may be blown from the air blowing portion 26 toward the outer peripheral side of the anode electrode 4.

FIG. 7 is a cross-sectional view of a main part showing a modified example of the anode cap 10, and the portion corresponding to FIG. 4 is designated by the same reference numeral.

As shown in FIG. 7, the outer peripheral edge of the protruding portion 24a of the cap base 24 is tapered downward, and a slit is secured between the outer peripheral edge of the protruding portion 24a and the lower outer peripheral edge of the cap base 24. , The anode cap 10 is provided with an air blowing portion 26 extending in an annular shape. When such a configuration is adopted, since the air blowing portion 26 is formed by the slit existing between the cap base 24 and the cap cover 25, it is not necessary to perform complicated drilling processing on the cap base 24, and the air blowing portion is eliminated. 26 can be easily formed.

1 Lid 2 Bottom plate 3 Plating tank 4 Anode electrode 5 Cathode electrode 10 Anode cap 15 Object to be plated 16 Anode bag 17 Rotating shaft 24 Cap base 24a Protruding part 24b Recessed groove (air supply passage)
25 Cap cover 25a Circular wall 26 Air blowout part 27 Air supply part 28 Tube 29 Through hole 30 Positioning part G Gap (air supply passage)
100 rotary plating equipment

Claims (6)

It is defined by a disk-shaped bottom plate that can rotate in both forward and reverse directions about the vertical axis, a cone-shaped lid integrally provided on the outer peripheral side wall of the bottom plate, and the bottom plate and the lid. A plating tank, a box-shaped anode electrode arranged substantially in the center of the plating tank, an anode cap holding the upper end of the anode electrode, and an outer peripheral surface that is exposed to the inner peripheral side of the plating tank. With a cathode electrode that forms part of the side wall,
A rotary plating apparatus characterized in that the anode cap is provided with an air blowing portion for blowing air toward the outer peripheral side of the anode electrode. In the rotary plating apparatus according to claim 1,
A rotary plating apparatus characterized in that the anode electrode is surrounded by an anode bag having a filter function, and air is blown from the air blowing portion toward the outer peripheral side of the anode bag. In the rotary plating apparatus according to claim 2,
The anode cap includes a cap base that holds the anode electrode and a cap cover that is joined and integrated so as to cover the cap base, and the air is provided between the cap base and the cap cover. A rotary plating device characterized in that an air supply passage leading to a blowout portion is provided. In the rotary plating apparatus according to claim 3,
A rotary plating apparatus characterized in that the cap base has a protruding portion that protrudes radially outward from the anode bag, and the air blowing portion is provided on the lower surface of the protruding portion. In the rotary plating apparatus according to claim 4,
A rotary plating apparatus characterized in that a plurality of air blowing portions are provided on the lower surface of the protruding portion at predetermined intervals in the circumferential direction. In the rotary plating apparatus according to claim 3,
The cap base has a protrusion protruding outward from the anode bag, and the air blowing portion is provided in an annular shape between the protrusion and the cap cover. Mold plating equipment.

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