JP6208821B1 - Surface treatment method and surface treatment apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform an electrochemical surface treatment while reducing the amount of a surface treatment liquid 2 used on only a part of a metal workpiece W. In the surface treatment method of the present invention, a metal workpiece W formed in a cylindrical shape or a disc shape is held on the tip side, and a rotary shaft 6 is rotatable about an axis. An electrochemical surface treatment is performed on a part of the outer peripheral side of the workpiece W while applying electric power to the workpiece W held on the tip end side of the rotating shaft 6 using the surface treatment apparatus 1 including At this time, a swing mechanism 10 that swings the tip end side of the rotary shaft in the vertical direction with respect to the base end side is provided on the middle side or the base end side of the rotary shaft 6, and the object to be processed is disposed below the rotary shaft 6. A surface treatment tank 9 containing the surface treatment liquid 2 for performing surface treatment is provided on the object W, and the rotary shaft 6 is swung in a tilt-down posture in which the distal end side of the rotary shaft 6 is positioned below the base end side. The surface treatment liquid 2 is used for a part on the outer peripheral side of the workpiece W by rotating the rotating shaft 6. Performing electrochemical surface treatment. [Selection] Figure 1

Description

  The present invention relates to a surface treatment method and a surface treatment apparatus for performing an electrochemical surface treatment on a part on the outer peripheral side of an object to be processed formed in a cylindrical shape or a disk shape.

Conventionally, luxury sedans and sports cars are sometimes equipped with vehicle wheels using aluminum or the like for the purpose of reducing the weight of the vehicle and dressing up the exterior. In general, such a vehicle wheel is often coated with a monotone such as silver, gold, black, and white on the surface of a metal such as aluminum.
However, in recent years, there has been an increase in the use of colorful paint on the chassis side, and in addition to the monotone colors such as silver, gold, black, and white that have been widely used in the past, some of the wheels are red, blue, and green. There is also a growing need for bright colors such as yellow.

In addition, some wheel manufacturers may wish to make their logos, brand names, and other marks stand out in vibrant colors to enhance the quality of their products and improve their brand image. .
In this way, when performing multicolor painting with most of the wheel as monotone color and only part of it as another color, first apply monotone paint to parts other than the mark using masking as a mask, Next, a method of painting a vivid color on the masked mark portion can be considered.

However, the painting method using masking is generally unsuitable for small and complicated objects such as marks. This is because even if masking is performed, the coating liquid or the like soaks from the gap of the tape or the like to the mark portion, and as a result, the outlines of characters and figures are blurred.
Therefore, a coating method as shown in Patent Document 1 has already been developed as a method of performing multicolor coating without using masking.

  That is, in the painting method used for the vehicle wheel of Patent Document 1, after forming the first color coating film on the base coating film formed on the entire disk portion (the entire wheel), a part of the spoke side surface or / And a part of the disk surface is scraped to expose the base metal of the disk part to form a metal exposed part, and the second electrodeposition paint having a color different from that of the first coating film on the metal exposed part The second color coating film was formed by electrodeposition coating. In this way, if the second color coating film is formed by electrodeposition coating on the exposed metal portion formed by polishing or grinding, it is not necessary to worry about the penetration of the coating liquid because masking is not performed. Therefore, if the technology of Patent Document 1 is used, it is possible to paint characters and figures with vivid colors on the surface of the vehicle wheel with a clear outline, and to obtain a vehicle wheel excellent in design and design. Is also possible.

JP2015-000584A

By the way, when actually performing electrodeposition coating on the vehicle wheel, an apparatus as shown in FIG. 6 is generally used.
That is, in the electrodeposition coating apparatus shown in FIG. 6, the vehicle wheel is placed on its side so that its rotational axis is directed in the vertical direction, and the electrodeposition coating treatment liquid is completely immersed in the liquid. Immerse in (surface treatment solution). Then, if the vehicle wheel is rotated while being immersed in the liquid, and further an electric current is passed between the processing tank containing the processing liquid and the rotating shaft, the electrodeposition coating is performed on the vehicle wheel. Is possible.

However, in the case of the apparatus of FIG. 6 in which the vehicle wheel is completely immersed in the processing liquid, it is absolutely necessary to prepare a large amount of the processing liquid in the tank in advance so that the vehicle wheel can be sufficiently immersed. Become. That is, in the electrodeposition coating method using the conventional apparatus, it is necessary to prepare a large amount of treatment liquid from the beginning even if the area to be electrodeposited is small.
In addition, when a vehicle wheel that has been painted is lifted from the tank, a large amount of processing liquid is taken out together with the vehicle wheel. There is also a problem that the amount of the processing solution used in vain increases.

  Thus, the problem that a large amount of processing liquid has to be prepared or the processing liquid is wasted is not a problem that is limited to the vehicle wheel. Even if other objects to be processed formed in a disk shape or a cylindrical shape, for example, objects to be processed such as a wheel cover, similar problems occur if electrodeposition coating is applied to a part thereof. That is quite conceivable.

  The present invention has been made in view of the above problems, and is prepared when an electrochemical surface treatment is performed on only a part of a metal workpiece to be formed in a cylindrical shape or a disk shape. Surface treatment method and surface treatment capable of performing treatment while reducing the amount of surface treatment liquid to be used and reducing the amount of surface treatment liquid to be used as much as possible and reducing the amount of surface treatment liquid to be taken out for each use. An object is to provide an apparatus.

In order to solve the above problems, the surface treatment method of the present invention employs the following technical means.
That is, the surface treatment method of the present invention is a surface having a rotating shaft that holds a metal object to be processed in a cylindrical shape or a disk shape on the tip side and is rotatable about an axis. When performing electrochemical surface treatment on a part of the outer peripheral side of the object to be processed while applying power to the object to be processed held on the tip side of the rotating shaft using a processing apparatus, the rotation A swing mechanism for swinging the distal end side of the rotating shaft in the vertical direction with respect to the proximal end side is provided on the middle side or the proximal end side of the shaft, and surface treatment is performed on the workpiece under the rotating shaft. A surface treatment tank containing a surface treatment liquid to be performed is provided, and the rotation shaft is rotated while the rotation shaft is swung to a tilt-down posture in which the distal end side of the rotation shaft is positioned below the base end side. Accordingly, use of the surface treatment solution only a portion of the outer peripheral side of the object to be processed And performing electrochemical surface treatment.

Preferably, the swing mechanism is configured to be able to swing the rotary shaft in a tilt-up posture in which a distal end side of the rotary shaft is located higher than a base end side, and tilt up from the tilt-down posture. When changing the posture of the rotary shaft to the posture, the change of the posture is temporarily stopped when the workpiece is separated from the surface of the surface treatment liquid, and the rotary shaft is swung by the swing mechanism. The surface treatment liquid remaining on the surface of the object to be treated may be removed by removing the surface treatment liquid by rotating the rotating shaft with a rotation driving mechanism while vibrating up and down at a shorter pitch .

  Preferably, a power source for generating electric power for surface-treating the object to be processed is supplied to the surface treatment apparatus, and a power supply unit for supplying electric power to the rotary shaft between the tip end side of the rotary shaft and the swing mechanism. And a liquid stop plate provided between the power supply unit and the object to be processed and extending in a direction intersecting with the axis of the rotation shaft, and the object to be processed in the tilt-up posture. The surface treatment of the object to be treated may be performed while the liquid stop plate prevents the surface treatment liquid dripping from the object from entering the power feeding unit.

Preferably, the surface treatment is electrodeposition coating, and the object to be treated is a vehicle wheel.
In addition, Preferably, the mark provided with the convex part protruded from the said outer peripheral side surface of the said vehicle wheel is formed, and it is good to perform the said electrodeposition coating with respect to the protrusion of the said convex part.
Preferably, power is supplied from a mounting portion provided on the front end side of the rotating shaft with respect to the back surface of the vehicle wheel on the side where the mark is provided.

Preferably, the surface treatment method includes an undercoating step of applying a paint to the entire surface of the vehicle wheel, and polishing to expose the metal surface at the tip while polishing the tip of the convex portion and leaving a coating film other than the tip. And the electrodeposition coating is preferably performed on the metal surface exposed in the polishing step.
On the other hand, the surface treatment apparatus of the present invention is provided with a long rotating shaft formed of a conductive material, and provided on the middle side of the rotating shaft, and rotates around the axis of the rotating shaft. A rotation drive mechanism that rotates the shaft, a swing mechanism that is provided on the midway side or the base end side of the rotation shaft, and that swings the distal end side of the rotation shaft in the vertical direction around the horizontal axis; A power supply for supplying power for surface treatment to the middle side or the base end side of the rotating shaft, and a metal workpiece to be provided at the tip of the rotating shaft and formed in a cylindrical shape or a disk shape are held. And a mounting portion for supplying the power to be processed to the object to be processed via the rotating shaft, and a surface treatment tank disposed under the tip side of the rotating shaft and storing a surface treatment liquid. In the surface treatment apparatus, the rocking mechanism has a proximal end at a distal end side of the rotating shaft. The rotary shaft can be swung in a tilt-down posture positioned below, and the rotary drive mechanism can rotate the rotary shaft in the tilt-down posture, and A surface using electricity for a part on the outer peripheral side while immersing a part on the outer peripheral side in the surface treatment liquid and holding the remaining part of the object to be processed outside the surface treatment liquid It is the structure which performs a process, It is characterized by the above-mentioned.

  According to the surface treatment method and the surface treatment apparatus of the present invention, when an electrochemical surface treatment is performed on only a part of a metal workpiece formed in a cylindrical shape or a disk shape, there is no preparation. It is possible to perform the treatment while reducing the amount of the surface treatment liquid to be used and the amount of the surface treatment liquid to be taken out every use as much as possible to reduce the amount of the surface treatment liquid used.

It is the front view which showed the surface treatment apparatus of this embodiment. It is front sectional drawing which showed the surface treatment apparatus of this embodiment during surface treatment. It is the figure which showed the electric power feeding part. It is the sectional view on the AA line of FIG. It is process drawing which showed the procedure of the surface treatment method of this embodiment. It is the figure which showed the conventional surface treatment method typically.

Hereinafter, embodiments of a surface treatment method and a surface treatment apparatus 1 according to the present invention will be described in detail with reference to the drawings.
The surface treatment method and the surface treatment apparatus 1 of this embodiment are electrochemical surface treatments using a surface treatment liquid 2 for a part of a metal workpiece W formed in a cylindrical shape or a disk shape. For example, surface treatment such as electrodeposition coating or electroplating is performed, and the amount of the surface treatment liquid 2 used in the surface treatment can be reduced.

  Specifically, as shown in FIG. 1, the surface treatment apparatus 1 of the present embodiment includes an apparatus main body 4 placed on a base surface or a floor surface F, and an axis that faces the apparatus main body 4 in the horizontal direction. And a rotating body 5 attached so as to be swingable around. The rotating body 5 includes a longer rotating shaft 6, a rotation driving mechanism 7 that rotates the rotating shaft 6 around the axis of the rotating shaft 6, and a metal provided at the tip of the rotating shaft 6. And an attachment portion 8 for holding a workpiece W to be processed. A swing mechanism 10 that swings the rotary body 5 with respect to the apparatus main body 4 is provided between the rotary body 5 and the apparatus main body 4 described above. By swinging, the rotation shaft 6 can change the inclination angle.

In addition, the surface treatment apparatus 1 includes a power source 11 that supplies power for surface treatment, a power supply unit 12 that supplies power from the power source 11 to the rotary shaft 6, and power that is supplied from the power supply unit 12 and the rotary shaft 6. And a mounting portion 8 for supplying the power to the object W to be processed.
Further, the surface treatment apparatus 1 includes a surface treatment liquid 2 for performing a surface treatment on the workpiece W, and in the case of this embodiment, a surface treatment tank 9 in which the surface treatment liquid 2 for electrodeposition coating is stored. . The surface treatment tank 9 is located below the front end side of the rotary shaft 6, and the workpiece W attached to the front end side of the rotary shaft 6 is swung in the surface treatment liquid 2 by swinging the rotary shaft 6. It can be immersed in.

The surface treatment method of the present invention includes processes other than electrodeposition coating, such as electroplating. However, in the following embodiment, the surface treatment method and the surface treatment apparatus 1 of the present invention will be described by taking electrodeposition coating as an example of the surface treatment.
Next, each member which comprises the surface treatment apparatus 1 of this embodiment, ie, the electrodeposition coating apparatus of this embodiment, is demonstrated in detail.

In the following description, the paper surface penetrating direction in FIG. 1 is referred to as the left-right direction when the surface treatment apparatus 1 is described, and the paper surface up-down direction in FIG. Further, the left-right direction in FIG. 1 is referred to as the front-rear direction. Further, the above-described directions are appropriately illustrated using arrows in the drawings.
First, the to-be-processed object W processed with the surface treatment apparatus 1 of this embodiment is demonstrated.

  The workpiece W is a member formed in a cylindrical shape or a disc shape, and is formed using a metal such as an aluminum alloy so that electrochemical surface treatment is possible. In addition, although the to-be-processed object W of this embodiment shown below is the wheel V for vehicles, in the to-be-processed object W which the surface treatment of this invention makes object, cylinders, such as a wheel cover, a brake disc rotor, etc., for example A metal member having a shape or a disk shape may be used.

The vehicle wheel V for performing the surface treatment in the present embodiment is a member used for attaching the tire to the vehicle, and can be mounted by fitting the tire on the outer peripheral side formed in a cylindrical shape. The vehicle wheel V is mounted on, for example, a high-end sedan or a sports car for the purpose of reducing the weight of the vehicle or dressing up the appearance.
Further, the vehicle wheel V includes a disk portion D that fits into the vehicle hub, and a rim portion R that is provided on the outer peripheral side of the disk portion D and on which a tire is mounted. A hub hole H that fits with the vehicle hub is formed on the center side of the disk portion D, and a spoke portion S that extends from the hub hole H toward the radially outer side is formed on the outer peripheral side of the hub hole H.

Next, the apparatus main body 4, the rotating body 5, the swing mechanism 10, the power supply 11, and the surface treatment tank 9 provided in the surface treatment apparatus 1 described above will be described in detail.
As shown in FIGS. 1, 2, and 4, the apparatus main body 4 is a member that supports the above-described rotating body 5 in a swingable manner, and a part of the swing mechanism 10 (the swing motor 18) is inside. It is formed in a bowl shape that can be accommodated. The apparatus main body 4 has a structure in which an upper member 4U and a lower member 4D, which are wide in the front-rear direction, are vertically connected by a connecting portion 4C having a narrower neck than the upper member 4U and the lower member 4D. The lower surface of the lower member 4D is formed into a flat surface, and can support the apparatus main body 4 while facing the floor surface F or the like. A worm gear 19 and a worm wheel 20 that meshes with the worm gear 19 are accommodated in the upper member 4U of the apparatus body 4. A swing motor 18 that generates a driving force for rotating the worm gear 19 is attached to the upper member 4U of the apparatus body 4 so as to protrude forward. Between the upper member 4U and the lower member 4D of the apparatus body 4, the above-described narrow neck connecting portion 4C is provided, and a plate-like reinforcing rib 21 is provided on the side (rear) of the connecting portion 4C. Is formed.

The upper member 4U of the apparatus main body 4 is provided with a swing shaft 22 penetrating the apparatus main body 4 in the left-right direction, and the swing shaft that faces the above-described rotating body 5 in the left-right direction via the swing shaft 22 is provided. It is supported so that it can swing around 22.
The rotating body 5 is a flange member having a substantially rectangular shape when viewed from the side. The rotating body 5 is disposed adjacent to the left side of the apparatus main body 4 described above and is around the axis of the swing shaft 22 with respect to the apparatus main body 4. Is swingably supported. The rotating body 5 supports the rotating shaft 6 so that the rotating shaft 6 is rotatable around the axis of the rotating shaft 6.

Taking the posture of FIG. 1 as an example, the rotating shaft 6 described above is attached to the rotating body 5 so as to penetrate both the rear side surface and the front side surface of the rotating body 5 in a communicating state. Specifically, the rotary body 5 rotatably supports the rotary shaft 6 with two bearings, a rear bearing 23 provided on the rear side surface of the rotary body 5 and a front bearing 24 provided on the front side surface. ing.
Further, the above-described swing shaft 22 is attached to the center side of the left and right side surfaces of the rotating body 5 so as to protrude toward the apparatus main body 4 side (left side). The axis of the swing shaft 22 and the axis of the rotary shaft 6 are arranged so as to intersect at substantially right angles.

  Further, a rotary drive motor 25 of a rotary drive mechanism 7 that rotates the rotary shaft 6 about its axis is disposed above the rotary body 5 so as to protrude upward. The tip of the drive shaft 25a of the rotary drive motor 25 extends into the rotary body 5, and the bevel gear that transmits the rotational drive force generated by the rotary drive motor 25 to the rotary shaft 6 is further attached to the tip of the drive shaft 25a. 30 and 31 are deployed.

  As shown in FIG. 1 to FIG. 3, the rotating shaft 6 is a long round bar-shaped member, and is supported on the rotating body 5 by the above-described two bearings 23 and 24 on the middle side in the longitudinal direction. Has been. A mounting portion 8 for attaching the vehicle wheel V is provided on the distal end side in the longitudinal direction of the rotating shaft 6 so that the vehicle wheel V can be attached. An actuator 27 for operating the attachment portion 8 is provided on the proximal end side in the longitudinal direction of the rotating shaft 6.

  Specifically, the rotating shaft 6 includes an outer cylinder member 28 whose inside is hollow, and a shaft member 29 that is slidably inserted in the longitudinal direction inside the outer cylinder member 28. The distal end of the shaft member 29 is connected to the mounting portion 8, and the proximal end of the shaft member 29 is connected to the actuator 27. That is, in the rotating shaft 6, when the actuator 27 is expanded and contracted, the shaft member 29 slides in the longitudinal direction of the rotating shaft 6, and the mounting portion 8 connected to the shaft member 29 expands or contracts in diameter. The vehicle wheel V can be fixed by the portion 8.

Bevel gears 30 and 31 that constitute the rotary drive mechanism 7 described above are provided inside the rotary body 5 on the midway side in the longitudinal direction of the rotary shaft 6 described above.
Furthermore, either or both of the outer cylinder member 28 and the shaft member 29 constituting the rotating shaft 6 described above are formed using a material such as a metal having conductivity. As described above, if a material having conductivity is used for the outer cylinder member 28 or the shaft member 29, it becomes possible to supply electric power to the vehicle wheel V through the rotating shaft 6, and to supply electric power for surface treatment. It can be supplied to the vehicle wheel V.

  The rotary drive mechanism 7 is attached to the rotary body 5 and also has a rotary drive motor 25 that extends the drive shaft 25 a inside the rotary body 5, and is attached to the drive shaft 25 a of the rotary drive motor 25 and is rotationally driven by the rotary drive motor 25. A first bevel gear 30 and a second bevel gear 31 which are meshed with the first bevel gear 30 and provided on the midway side of the rotary shaft 6. Specifically, the first bevel gear 30 described above is attached to the tip of the drive shaft 25 a of the rotation drive motor 25, and the first bevel gear 30 that meshes with the first bevel gear 30 in the middle of the rotation shaft 6. The two bevel gears 31 are attached, and the rotational shaft 6 can be rotationally driven by transmitting the rotational driving force generated by the rotational driving motor 25 to the rotational shaft 6. The rotational speed of the rotary shaft 6 is preferably 0.1 rpm to 10 rpm, for example.

The mounting portion 8 is a member used for mounting the vehicle wheel V on the tip side of the rotating shaft 6. The mounting portion 8 is inserted into the hub hole H of the vehicle wheel V described above, and can be fixed so as not to come off the vehicle wheel V by expanding the diameter toward the outside of the diameter inside the hub hole H. ing.
Specifically, the mounting portion 8 includes a lock member 32 that can be increased in diameter toward the outer side, and a taper member 33 that increases or decreases the diameter of the lock member 32.

  The lock member 32 is a member formed in a cylindrical shape, and the outer diameter thereof is substantially the same as or slightly smaller than the inner diameter of the hub hole H, and is inserted into the hub hole H of the vehicle wheel V. It is possible. Further, the outer peripheral surface of the lock member 32 has substantially the same curvature as the inner peripheral surface of the hub hole H so that the lock member 32 can be brought into surface contact with the inner peripheral surface of the hub hole H when the diameter of the lock member 32 is increased. It is formed to have.

A slit-like cut 40 is formed on the distal end side of the lock member 32 along a direction parallel to the axis of the rotary shaft 6. A plurality of the notches 40 are formed in the circumferential direction of the lock member 32, and the deformation along the radial direction of the lock member 32, in other words, the lock member 32 can be expanded or contracted.
On the inner peripheral side of the lock member 32, a tapered surface 32 a is formed such that the diameter increases from the proximal end side to the distal end side of the rotating shaft 6. Further, a taper member 33 that contacts the taper surface 32a in a surface state on the outer peripheral side is provided on the inner peripheral side of the taper surface 32a.

  The taper member 33 is a substantially cylindrical member having an outer peripheral surface 33a whose outer diameter gradually increases from the proximal end side toward the distal end side. The outer peripheral surface 33a is an inner peripheral surface of the lock member 32 described above ( The tapered surface 32a) can be contacted in a surface state. The shaft member 29 described above is connected to the proximal end side of the taper member 33, and by sliding the shaft member 29 in the axial direction of the rotating shaft 6, the outer peripheral surface of the taper member 33 is changed to the inner periphery of the lock member 32. Since it moves in the axial direction while being in surface contact with the surface, the lock member 32 increases or decreases in diameter outward.

The actuator 27 on the proximal end side of the rotating shaft 6 is provided with a biasing member 36 that biases the shaft member 29 in the direction of retracting toward the proximal end side, and the air supplied to the actuator 27 When the pressure of a pressure medium such as oil or oil is reduced, the urging force of the urging member 36 becomes dominant and the actuator 27 can be degenerated.
Further, the taper member 33 and the lock member 32 constituting the mounting portion 8 are formed using a material such as a metal having conductivity in the same manner as the rotating shaft 6, and the electric power that has been electrically driven from the rotating shaft 6 is obtained. It also plays a role of transmitting to the vehicle wheel V in surface contact with the outer peripheral side.

  The swing mechanism 10 is provided between the rotating body 5 and the apparatus main body 4 described above, and swings the rotating body 5 about an axis that faces the left-right direction with respect to the apparatus main body 4. Specifically, the swing mechanism 10 includes a swing motor 18 attached so as to protrude from the front side surface of the apparatus body 4 and a drive shaft 18a of the swing motor 18 extending rearward from the swing motor 18. The worm gear 19 attached to the tip end side of the worm gear 19 and the worm wheel 20 attached to the worm gear 19 so as to rotate together with the rotator 5 are provided. That is, when the swing motor 18 is driven, the worm gear 19 of the drive shaft rotates and the worm wheel 20 meshing with the worm gear 19 rotates, so that the rotating body 5 can swing with respect to the apparatus main body 4.

  In other words, when the swing motor 18 is rotated in one direction using the swing mechanism 10 described above, the rotating body 5 swings toward the one side around the swing shaft 22 facing in the left-right direction with respect to the apparatus body 4. Then, the rotary shaft 6 is inclined in a forwardly lowered state so that the distal end side is positioned below the proximal end side. The posture of the rotating shaft 6 in which the distal end side of the rotating shaft 6 is positioned below the proximal end side is referred to as a tilt-down posture. In this chilled down posture, the height of the mounting portion 8 provided on the distal end side of the rotating shaft 6 is lowered, and the position of the vehicle wheel V attached to the mounting portion 8 is also lowered. Can be immersed in the surface treatment liquid 2 stored in the surface treatment tank 9. As this chilled down posture, for example, the rotary shaft 6 is inclined at 20 ° to 70 ° with respect to the horizontal direction.

  On the other hand, when the oscillating motor 18 is rotated in the other direction using the oscillating mechanism 10 described above, the rotating body 5 oscillates toward the other side around the oscillating shaft 22 that faces the apparatus main body 4 in the left-right direction. Then, the rotary shaft 6 is inclined in a forwardly raised state so that the distal end side is located above the proximal end side. The posture of the rotating shaft 6 in which the distal end side of the rotating shaft 6 is positioned higher than the proximal end side is referred to as a tilt-up posture.

Thus, it can be said that the swing mechanism 10 described above is configured to switch the posture of the rotating shaft 6 between the tilt-up posture and the tilt-down posture.
The power source 11 generates power for surface-treating the workpiece W. Direct current power is generated from the power source 11, and one electrode (anode) is connected to the power feeding unit 12 via the wiring 42, and the other electrode (cathode) is connected to the surface treatment tank 9. ing.

  The power feeding unit 12 supplies the above-described direct-current power to the rotating shaft 6, and includes a pair of metal holding bodies 43 that hold the rotating shaft 6 (outer cylinder member 28) from the outer peripheral side, and these A guide portion 44 that guides the sandwiching bodies 43 so as to be able to come into contact with and separate from each other, and a biasing means 45 (spring) that biases the sandwiching bodies 43 toward each other in a direction in which they are always close to each other. One end of the above-described wiring 42 is connected to the sandwiching body 43 provided in the power feeding unit 12, and the power feeding unit 12 supplies power to the rotating shaft 6 sandwiched between the two sandwiching bodies 43 through the wiring 42. It is possible.

  The surface treatment tank 9 is a bottomed container that opens upward, and can store the surface treatment liquid 2 therein. The surface treatment tank 9 is disposed below the front end side of the rotary shaft 6 and a part of the outer peripheral side of the vehicle wheel V attached to the front end of the rotary shaft 6 in a tilted down position is stored inside. It can be immersed in the surface treatment liquid 2. Further, the other end of the wiring 42 described above is connected to the surface treatment tank 9.

By the way, in general, when a vehicle wheel V that is often monotone painted such as silver, gold, black, and white is used as a workpiece W to be surface-treated, a mark such as a company logo or a brand name is provided on a part of the vehicle wheel V. In some cases, it may be desirable to make L stand out in vivid colors to enhance the quality of the product or to improve the image of its own brand.
Specifically, the above-described mark L is as shown in an enlarged view in FIG. 1, and a convex portion 38 protruding from the surface is formed on the surface of the vehicle wheel V. The tip is electrodeposited with vivid colors. In addition, the mark L is configured such that a person who looks at the vehicle wheel V can recognize a character shape or a graphic shape such as a logo or a brand name by combining these convex portions 38. Such a mark L is generally formed on the outer peripheral side of the vehicle wheel V, in other words, on the outer peripheral side of the rim R, and the electrodeposition coating is applied in a color different from the place other than the mark L. It is to do.

  In other words, when electrodeposition coating is performed on the above-described mark L, the electrodeposition coating such as monotone is first applied to the entire surface of the vehicle wheel V including the mark L, and then the electrodeposition coating such as monotone is performed. An undercoating step of applying a paint is performed on the mark L on which has been performed. For the vehicle wheel V that has been coated by this undercoating process, the protruding end of the convex portion 38 constituting the mark L is polished or ground to leave a coating film other than the protruding end while leaving the protruding metal surface 41. A polishing step is performed to expose. Thus, for the vehicle wheel V in which the protruding end of the convex portion 38 is exposed as the metal surface 41, a brightly colored coating film is locally formed by electrodeposition coating using the conventional surface treatment apparatus 101. be able to.

At this time, as shown in FIG. 6, the conventional surface treatment apparatus 101 completely immerses the vehicle wheel V in the surface treatment liquid 102 while lying on its side so that the rotating shaft 106 is directed vertically. Electrodeposition coating is performed on a part of the surface (the tip of the mark L) while rotating the vehicle wheel V immersed in the liquid.
However, when electrodeposition coating is performed with the apparatus configuration as shown in FIG. 6, it is necessary to completely immerse the vehicle wheel V in the coating material. Therefore, a large amount of coating material (surface treatment liquid) is inevitably contained in the tank. It is necessary to prepare.

In addition, when the vehicle wheel V that has been painted is lifted from the tank, a large amount of paint is taken out together with the vehicle wheel V. There is also a problem that the amount of paint used in vain increases.
Therefore, in the surface treatment method of the present invention, the workpiece is rotated by rotating the rotary shaft 6 while tilting the rotary shaft 6 in a tilt-down posture in which the distal end side of the rotary shaft 6 is positioned below the base end side. While immersing a part of the outer peripheral side of W in the surface treatment liquid 2 and holding the remaining part of the workpiece W outside the surface treatment liquid 2, it is electrochemical with respect to a part of the outer peripheral side. A surface treatment (using electricity) is performed. That is, in the surface treatment method of the present invention, the outer peripheral side of the vehicle wheel V on which the mark L is formed is moved more than the other part of the vehicle wheel V by swinging the rotating shaft 6 in a tilted down posture. Is made as low as possible, and electrodeposition coating is performed on the tip of the mark L.

Specifically, the surface treatment method of the present embodiment is preferably performed according to a procedure as shown in FIG.
That is, paint or the like is applied to the entire surface of the vehicle wheel V including the mark L, and then only the protruding end of the mark L is polished or ground to expose the metal surface 41. For the vehicle wheel V with the metal surface 41 exposed at the protruding end of the mark L as described above, foreign matters are first removed as “preparation work”. The removal of the foreign matter is performed by air-blowing the entire vehicle wheel V using compressed air and blowing away the foreign matter.

  Next, the vehicle wheel V from which the foreign matter has been removed is mounted on the mounting portion 8 of the rotating shaft 6 in the tilt-up posture. Specifically, the mounting portion 8 is inserted into the hub hole H of the vehicle wheel V, and the actuator 27 provided on the base end side of the rotating shaft 6 is retracted in a state where the mounting portion 8 is inserted. Then, the shaft member 29 connected to the actuator 27 slides toward the base end side (actuator 27 side) of the rotating shaft 6, and the taper member 33 of the mounting portion 8 connected to the tip end side of the shaft member 29 is also the base end side. Slide toward. At this time, the lock member 32 is deformed toward the radially outer side in accordance with the slide of the taper member 33 toward the proximal end of the rotating shaft 6, and is fixed so that the vehicle wheel V is not pulled out by the lock member 32 having an enlarged diameter. Therefore, the vehicle wheel V can be set on the attachment portion 8.

  When the vehicle wheel V is thus set on the mounting portion 8, the power feeding portion 12 is attached to the rotating shaft 6, and the anode of the power source 11 is electrically connected to the rotating shaft 6 via the wiring 42 and the power feeding portion 12. . The wiring 42 extending from the cathode of the power supply 11 is also electrically connected to the surface treatment tank 9 using a clip or the like. If it does in this way, it will prepare so that electricity can be supplied to the wheel V for vehicles.

After the wiring 42 is connected, it is checked whether or not continuity is secured using a tester or the like, and after checking the continuity, the rotating shaft 6 in the tilt-up posture is changed to the tilt-down posture using the swing mechanism 10.
Specifically, the oscillating motor 18 is rotated to drive the worm gear 19 to rotate. Then, the worm wheel 20 meshed with the worm gear 19 tries to rotate in accordance with the rotation of the worm gear 19. However, since the worm wheel 20 can rotate integrally with the rotating body 5, the rotating body 5 itself swings around the swing shaft 22 when the worm gear 19 is driven to rotate. As a result, the rotating shaft 6 supported by the rotating body 5 also swings in accordance with the swing of the rotating body 5, and the posture of the rotating shaft 6 changes from the tilt-up posture to the tilt-down posture.

  In the tilt-down posture, only the mark L formed on the outer peripheral side of the vehicle wheel V is immersed in the surface treatment liquid 2 so that the portion other than the mark L is located above the liquid surface of the surface treatment liquid 2. become. In this tilt-down position, the vehicle wheel V is rotated by one rotation as a “paint familiarity” operation, and the vehicle wheel V is applied to the electrodeposition coating treatment liquid while removing bubbles remaining on the vehicle wheel V. Make it.

  When the “paint familiarity” operation is completed in this way, electric power is supplied from the power source 11 to the vehicle wheel V, and electrodeposition coating is started. That is, only the outer peripheral side of the vehicle wheel is immersed in the electrodeposition coating treatment liquid (surface treatment liquid 3), and the vehicle wheel V is rotated while power is supplied from the power source 11 to the vehicle wheel V. Electrodeposition coating is performed on the metal surface 41 at the tip. If electrodeposition coating is performed under such processing conditions, the vehicle wheel V, which is the object to be processed, rotates, so that a coating film can be formed evenly without stirring the processing liquid. .

With respect to the vehicle wheel V that has been subjected to electrodeposition coating for a predetermined time in this way, the rotating shaft 6 is swung using the swinging mechanism 10, and the posture of the rotating shaft 6 is tilted from the tilt-down posture. Change to the up position.
When the posture of the rotating shaft 6 is changed, the swinging operation of the rotating shaft 6 is temporarily stopped when the vehicle wheel V (the workpiece W) is separated from the liquid surface of the surface treatment liquid 3. Then, the rotary shaft 6 is vibrated up and down around the stop position using the swing mechanism 10. The vibration of the rotary shaft 6 is performed by switching the rotation direction of the swing motor 18 at a short pitch between forward and reverse. Further, while rotating the rotating shaft 6 using the swing mechanism 10, the rotating shaft 6 is also rotated by the rotation driving mechanism 7. Specifically, the vibration of the rotation shaft 6 is preferably caused to vibrate at a rotation speed of 0.1 times / minute to 10 times / minute. In this way, the surface treatment liquid 2 remaining on the surface of the vehicle wheel V can be repelled and returned to the surface treatment tank 9, and the amount of the surface treatment liquid 2 taken out from the surface treatment tank 9 can be further reduced. Can do.

  When the repelling of the surface treatment liquid 2 is completed, the rotating shaft 6 is again swung to the tilt-up posture using the swinging mechanism 10, and then the processed vehicle wheel V is removed from the rotating shaft 6. Finally, the vehicle wheel V removed in the “cleaning” step is showered and cleaned, and water droplets remaining on the surface after cleaning are wiped off, and then the coating is baked in the “baking” step. Do. The electrodeposition coating on the vehicle wheel V is completed by the above procedure.

In the case of the surface treatment method described above, although the effect varies somewhat depending on the shape of the vehicle wheel V and the position where the mark L is formed, the amount of the surface treatment liquid 2 that must be prepared in the surface treatment tank 9 is Can be reduced.
That is, the amount of the surface treatment liquid 2 stored in the surface treatment tank 9 is deep enough to immerse the mark L when the rotary shaft 6 is tilted down, and the vehicle wheel V What is necessary is just to set it as the depth which does not collide with the tank bottom of the surface treatment tank 9. Therefore, an amount of the treatment liquid that can completely immerse the vehicle wheel V is not necessary, and the amount of the treatment liquid can be greatly reduced.

Further, since only part of the outer peripheral side of the vehicle wheel is immersed in the surface treatment liquid 2, even if the vehicle wheel is taken out after the surface treatment, the surface treatment liquid 2 is not often taken out. Therefore, in the surface treatment method described above, the amount of the surface treatment liquid 2 used can be reduced as much as possible.
Further, the surface treatment liquid 2 remaining on the surface of the vehicle wheel V is repelled and removed by rotating the rotation shaft 6 by the rotation drive mechanism 7 while vibrating the rotation shaft 6 up and down by the swing mechanism 10. In addition, the amount of the processing liquid taken out of the tank can be greatly reduced.

Therefore, in the surface treatment method of the present invention, the amount of the surface treatment liquid 2 that must be prepared from the beginning and the amount of the treatment liquid taken out of the tank are further suppressed, and the amount of the surface treatment liquid 2 used is extremely low. It becomes possible to do.
Preferably, a liquid stop plate 39 that extends in a direction intersecting the axis of the rotary shaft 6 is provided between the power supply unit 12 and the workpiece W described above, and the workpiece is processed in the tilt-up posture. It is preferable to prevent the surface treatment liquid 2 dripping from the object W from entering the power feeding unit 12 with the liquid stop plate 39.

  Specifically, the liquid stop plate 39 is a disk-like member extending in a direction orthogonal to the axis of the rotation shaft 6, and is substantially equal to the outer diameter of the vehicle wheel V or the vehicle wheel V The outer diameter is smaller than the outer diameter. If such a liquid stop plate 39 is provided, even when the surface treatment liquid 2 remaining on the surface of the vehicle wheel V is dropped when the rotary shaft 6 is inclined in the tilt-up posture as shown in FIG. The dropped surface treatment liquid 2 is blocked by the liquid stop plate 39 and does not reach the rocking mechanism 10 or the rotation drive mechanism 7, and the dropped surface treatment liquid 2 does not cause corrosion of the apparatus.

  Finally, the surface treatment apparatus 1 of the present invention is provided with a rotating shaft 6 formed in a long length using a material having conductivity, and provided on the middle side of the rotating shaft 6. And a rotation drive mechanism 7 for rotating the rotary shaft 6 and a rocker provided on the middle side or the base end side of the rotary shaft 6 to swing the tip end side of the rotary shaft 6 up and down around the horizontal axis. A moving mechanism 10; a power source 11 for supplying power for surface treatment to the middle side or the base end side of the rotary shaft 6; and a metal that is provided at the tip of the rotary shaft 6 and has a cylindrical shape or a disc shape. A mounting portion 8 for holding the workpiece W and supplying the power W sent through the rotating shaft 6 to the workpiece W, and a surface treatment liquid 2 provided below the tip side of the rotating shaft 6 A surface treatment apparatus 1 having the surface treatment tank 9 formed. The swing mechanism 10 can swing the rotary shaft 6 in a tilt-down posture in which the distal end side of the rotary shaft 6 is located below the base end side, and the rotational drive mechanism 7 has a tilt-down posture. The rotary shaft 6 thus made can be rotated. Further, a part on the outer peripheral side of the workpiece W is immersed in the surface treatment liquid 2 and the remaining portion of the workpiece W is held outside the surface treatment liquid 2 while being partly on the outer peripheral side. On the other hand, it is configured to perform surface treatment using electricity.

If it is such a surface treatment apparatus 1, when performing electrochemical surface treatment only to a part of metal to-be-processed object W formed in the cylindrical shape or the disk shape, you have to prepare. The amount of the surface treatment liquid 2 and the amount of the surface treatment liquid 2 taken out for each use can be reduced as much as possible to reduce the amount of the surface treatment liquid 2 used.
The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. In particular, in the embodiment disclosed this time, matters that are not explicitly disclosed, for example, operating conditions and operating conditions, various parameters, dimensions, weights, volumes, and the like of a component deviate from a range that a person skilled in the art normally performs. Instead, values that can be easily assumed by those skilled in the art are employed.

  For example, in the above-described embodiment, the configuration in which vibration is applied to the vehicle wheel V (the workpiece W) by switching the rotation direction of the swing motor 18 is exemplified. However, the means for vibrating the rotating shaft 6 may not be the swing motor 18. A vibration means using an air cylinder or an electric motor may be separately provided in the vicinity of the rotation shaft 6 or the rotation shaft 6, and the rotation shaft 6 may be vibrated using this vibration means.

  In the above-described embodiment, when the vehicle wheel V after electrodeposition coating is carried out from the surface treatment apparatus 1 to the outside of the apparatus, the rotating shaft 6 is once switched from the tilt-down position to the tilt-up position, Wheel V was being carried out. However, when the vehicle wheel V after electrodeposition coating is carried out, the vehicle wheel V is rotated by rotating the rotary shaft 6 about the axis facing the vertical direction while keeping the rotary shaft 6 in the tilted down posture. You may carry out, moving horizontally. In the case of such a carry-out mechanism, by providing a washing tank or the like on the rotation path of the vehicle wheel V, it is possible to perform a process such as washing the vehicle wheel V during the carry-out.

  Further, in the above-described embodiment in which the rotation shaft 6 is rotated around the vertical axis, the surface treatment tank 9 can be moved up and down or can be swung. For example, when the vehicle wheel V after electrodeposition coating is carried out from the surface treatment apparatus 1, the surface treatment tank 6 is lowered or the surface treatment tank 6 is slightly inclined downward. In this way, the position of the surface treatment tank 9 is lowered, and the tank wall of the surface treatment tank 9 does not interfere with the movement of the vehicle wheel V during rotation. Unloading is possible.

DESCRIPTION OF SYMBOLS 1 Surface treatment apparatus 2 Surface treatment liquid 4 Apparatus main body 4U Upper member of apparatus main body 4D Lower member of apparatus main body 4C Connection part of apparatus main body 5 Rotating body 6 Rotating shaft 7 Rotation drive mechanism 8 Mounting part 9 Surface treatment tank 10 Oscillation mechanism DESCRIPTION OF SYMBOLS 11 Power supply 12 Electric power feeding part 18 Oscillating motor 19 Worm gear 20 Worm wheel 21 Reinforcing rib 22 Oscillating shaft 23 Rear bearing 24 Front side bearing 25 Rotation drive motor 25a Rotation drive motor drive shaft 27 Actuator 28 Outer cylinder member 29 Shaft member 30 First bevel gear 31 Second bevel gear 32 Lock member 32a Tapered surface 33 of lock member 33 Tapered member 33a Peripheral surface of taper member 36 Energizing member 38 Convex portion 39 Liquid stop plate 40 Notch 42 Wiring 43 Holding body 44 Guide portion 45 With Means 101 Conventional surface treatment device 106 Conventional surface treatment device Axis 102 Wheel surface treatment liquid F floor W to be treated V vehicle of the conventional surface treatment apparatus D disc portion R rim H hub hole S spoke L mark

Claims (8)

Using a surface treatment apparatus that holds a metal workpiece formed in a cylindrical shape or a disk shape on the tip side and includes a rotation shaft that is rotatable about an axis, When performing electrochemical surface treatment on a part of the outer peripheral side of the object to be processed while applying electric power to the object to be processed held on the tip side,
A swinging mechanism for swinging the tip end side of the rotating shaft in the vertical direction with respect to the base end side is provided on the middle side or the base end side of the rotating shaft, and the surface of the object to be processed is below the rotating shaft. A surface treatment tank containing a surface treatment liquid for treatment is provided,
By rotating the rotating shaft while swinging the rotating shaft in a tilt-down posture in which the distal end side of the rotating shaft is positioned below the base end side,
An electrochemical surface treatment using the surface treatment liquid on only a part of the outer peripheral side of the object to be treated. The swing mechanism is configured to swing the rotary shaft in a tilt-up posture in which the distal end side of the rotary shaft is positioned higher than the base end side,
When changing the attitude of the rotary shaft from the tilt-down attitude to the tilt-up attitude,
When the object to be processed is separated from the surface of the surface treatment liquid, the posture change is temporarily stopped, and the rotational shaft is vibrated up and down at a pitch shorter than the rocking motion by the rocking mechanism, and is rotationally driven. The surface treatment method according to claim 1, wherein the surface treatment liquid remaining on the surface of the object to be treated is repelled and removed by rotating a rotation shaft by a mechanism. A power source that generates electric power for surface-treating the object to be processed to the surface treatment apparatus, a power supply unit that supplies power to the rotary shaft between a tip end side of the rotary shaft and the swing mechanism, and the power supply unit And a liquid stop plate that is provided between the workpiece and the workpiece, and spreads in a direction intersecting with the axis of the rotary shaft,
The surface treatment of the object to be treated is performed while the liquid stop plate prevents the surface treatment liquid dripping from the object to be treated during the tilt-up posture from entering the power feeding unit. 3. The surface treatment method according to 1 or 2. The surface treatment is electrodeposition coating;
The surface treatment method according to claim 1, wherein the object to be treated is a vehicle wheel. On the outer peripheral side surface of the vehicle wheel, a mark having a convex portion protruding from the surface is formed,
The surface treatment method according to claim 4, wherein the electrodeposition coating is performed on a protruding end of the convex portion. 6. The surface treatment method according to claim 4, wherein power is supplied from a mounting portion provided on a tip end side of the rotation shaft with respect to a back surface of the vehicle wheel on a side where the mark is provided. The surface treatment method includes:
An undercoating step of applying paint to the entire surface of the vehicle wheel;
Polishing the protruding end of the convex portion and exposing the metal surface of the protruding end while leaving a coating film other than the protruding end, and
The surface treatment method according to any one of claims 4 to 6, wherein the electrodeposition coating is performed on the metal surface exposed in the polishing step. A rotating shaft formed in a long length using a material having conductivity;
A rotation drive mechanism that is provided in the middle of the rotation shaft and rotates the rotation shaft about the axis of the rotation shaft;
A swing mechanism provided on the middle side or the base end side of the rotary shaft, and swinging the tip end side of the rotary shaft in the vertical direction around a horizontal axis;
A power supply for supplying power for surface treatment to the middle side or the base end side of the rotating shaft;
A mounting portion that is provided at the tip of the rotating shaft and holds a metal object to be processed which is formed in a cylindrical shape or a disk shape, and which supplies the electric power sent through the rotating shaft to the object to be processed; ,
A surface treatment tank disposed below the front end side of the rotating shaft and having a surface treatment liquid stored therein,
The swing mechanism is configured to swing the rotary shaft in a tilt-down posture in which the distal end side of the rotary shaft is positioned below the base end side,
The rotation drive mechanism is configured to be able to rotate the rotation shaft in the tilt-down posture,
While immersing a part of the outer peripheral side of the object to be processed in the surface treatment liquid and holding the remaining part of the object to be processed outside the surface treatment liquid, A surface treatment apparatus characterized in that the surface treatment is performed using electricity.